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USACE / NAVFAC / AFCEC / NASA
UFGS-23 51 43.00 20 (February 2010)
----------------------------------Preparing Activity: NAVFAC
Superseding
UFGS-23 51 43.00 20 (April 2006)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2016
**************************************************************************
SECTION TABLE OF CONTENTS
DIVISION 23 - HEATING, VENTILATING, AND AIR CONDITIONING (HVAC)
SECTION 23 51 43.00 20
DUST AND GAS COLLECTOR, DRY SCRUBBER AND FABRIC FILTER TYPE
02/10
PART 1
GENERAL
1.1
REFERENCES
1.2
GENERAL REQUIREMENTS
1.2.1
Mechanical General Requirements
1.2.2
Electrical General Requirements
1.2.3
General Application of Reference Specifications
1.2.4
Steam Generators
1.3
DEFINITIONS
1.4
DESIGN REQUIREMENTS
1.4.1
Detail Drawing
1.4.1.1
Dust Collector System
1.4.1.2
Dust Collector Components
1.4.1.3
Piping Drawings
1.4.1.4
Wiring Diagrams
1.4.1.5
Schematic Control Diagrams
1.4.1.6
Printed Circuitboards Information
1.4.2
Calculations
1.4.3
Additional Product Data
1.5
QUALITY ASSURANCE
1.5.1
Manufacturer Experience
1.5.1.1
Auxiliary Manufacturer Experience
1.5.2
Certificates
1.5.2.1
Pipe Welding Procedures
1.5.2.2
Weld Testing Procedures
1.5.2.3
Welding Shops
1.5.2.4
Qualifying Experience Certification
1.5.2.5
Factory Test Certification
1.5.2.6
Dry FGD System Experience Certification
1.5.3
Test Reports
1.5.3.1
Pump Tests Reports
1.5.3.2
Damper Tests Reports
1.5.3.3
Dust Collector Model Tests Report
1.5.3.4
Instrument Calibration and Testing
1.5.4
Records
1.5.5
Model Test
SECTION 23 51 43.00 20
Page 1
1.5.6
Tabulations
1.6
SUBMITTALS
1.7
DELIVERY AND STORAGE
1.8
AMBIENT ENVIRONMENTAL REQUIREMENTS
1.9
EXPERIENCE CLAUSE
1.9.1
Certificate
1.10
OPERATOR TRAINING PROGRAM
1.10.1
Training Manuals
1.10.2
Testing Program
1.10.3
Classroom Instruction
1.10.4
Field Instructions
1.10.5
Video Recording
1.11
MODEL DELIVERY
1.12
POSTED OPERATING INSTRUCTIONS
PART 2
PRODUCTS
2.1
APPLICATION
2.2
EQUIPMENT AND MATERIALS PROVIDED UNDER THIS CONTRACT
2.2.1
Spray Dryer Sulfur Dioxide Absorbers
2.2.2
Fabric Filter Baghouse
2.2.3
Lime Slurry Preparation System
2.2.4
Pumps, Valves, and Motors
2.2.5
Ductwork and Draft Equipment
2.2.6
Instrumentation and Control Devices
2.2.7
Structural and Miscellaneous Steel
2.3
SITE FABRICATED AUXILIARY CONSTRUCTION
2.4
SITE CONDITIONS
2.5
OPERATING INSTRUCTIONS
2.5.1
Steam Generators
2.5.2
Fuels
2.5.3
Lime
2.5.4
Slaking Water
2.5.5
Process Water
2.5.6
Compressed Air
2.6
DESIGN PARAMETERS
2.6.1
Expected Flue Gas Conditions
2.6.2
Spray Dryer Absorbers
2.6.3
Fabric Filter Baghouses
2.6.4
Lime Slurry Preparation System
2.6.5
Ductwork
2.6.6
Induced Draft Fans
2.6.7
Sulfur Dioxide Removal Performance Guarantees
2.6.8
Particulate Removal Performance Guarantees
2.6.9
Lime Slurry System Performance Guarantees
2.6.10
Draft Equipment Performance Guarantees
2.6.11
FGD System Operational Performance Guarantees
2.7
SPRAY DRYER ABSORBERS
2.7.1
Spray Dryer Absorber Vessel
2.7.2
Spray Dryer Atomizers
2.7.2.1
Rotary Atomizers
2.7.2.2
Two-Fluid Nozzle Atomizers
2.7.2.3
Spare Equipment
2.7.3
Monorail and Hoist
2.7.4
Absorber Product Removal System
2.8
FABRIC FILTER BAGHOUSES
2.8.1
Pulse Jet Cleaning Systems
2.8.1.1
Spare Equipment
2.8.2
Reverse Gas Cleaning System
SECTION 23 51 43.00 20
Page 2
2.8.2.1
Spare Equipment
2.8.3
Bag Guarantee
2.8.4
Bag Quality Assurance
2.8.5
Hoppers
2.8.6
Manifolds and Draft Equipment
2.9
LIME SLURRY PREPARATION SYSTEM
2.9.1
Lime Storage and Feed Bin
2.9.2
Lime Slakers
2.10
PUMPS, VALVES, MOTORS
2.10.1
Pumps
2.10.1.1
Centrifugal Pumps
2.10.1.2
Vertically Split-Case Rubber-Lined Pumps
2.10.1.3
Vertically Split-Case Pumps
2.10.1.4
Vertical Wet Pit Pumps
2.10.1.5
Factory Test and Reports
2.10.2
Valves and Piping
2.10.2.1
Valves
2.10.2.2
Piping
2.10.2.3
Fittings
2.10.2.4
Pipe Hangers
2.10.2.5
Shipping and Handling
2.10.3
Electric Motor Drives and Motor Control Center
2.10.3.1
Motors Rated 3/8 kW 1/2 Horsepower and Smaller
2.10.3.2
Motors Rated 1/2 Through 149 kW 3/4 Through 199 H.P.
2.10.3.3
Motors Rated 150 Kilowatt 200 Horsepower and Larger
2.10.3.4
Motor Control Centers
2.10.3.5
Factory Tests
2.11
DUCTWORK AND DRAFT EQUIPMENT
2.11.1
Ductwork
2.11.1.1
Reverse Air Ductwork
2.11.2
Expansion Joints
2.11.3
Dampers
2.11.3.1
Seal Air Systems
2.11.3.2
Louver Dampers
2.11.3.3
Poppet Dampers
2.11.3.4
Guillotine Dampers
2.11.4
Mechanical Draft Equipment
2.11.4.1
Fan Housing
2.11.4.2
Fan Rotors and Shafts
2.11.4.3
Bearings
2.11.4.4
Motor Drive
2.11.4.5
Induced Draft Fan
2.11.4.6
Reverse Air Fan
2.11.5
Painting
2.11.6
Factory Tests
2.11.6.1
Damper Tests
2.11.6.2
Mechanical Draft Equipment Tests
2.12
INSTRUMENTATION AND CONTROLS
2.12.1
System Operation
2.12.1.1
Lime Slurry Preparation
2.12.1.2
Spray Dryer Absorbers
2.12.1.3
Baghouses
2.12.2
Analog Control Systems
2.12.2.1
Electronic Control Modules
2.12.2.2
Input and Output Signals
2.12.2.3
System Electrical Power and Power Supplies
2.12.2.4
Operating Stations
2.12.2.5
Control Drive
2.12.3
Digital Control Systems
SECTION 23 51 43.00 20
Page 3
2.12.3.1
Wired Solid-State Logic
2.12.3.2
Solid-State Programmable Logic
2.12.4
Flue Gas Cleaning System Panelboard and System Cabinets
2.12.4.1
Construction
2.12.4.2
Finish
2.12.4.3
Nameplates
2.12.4.4
Graphics
2.12.4.5
Wiring
2.12.4.6
Power Supplies and Switches
2.12.4.7
Lights and Indicators
2.12.4.8
Counters and Meters
2.12.4.9
Recorders
2.12.4.10
Annunciators
2.12.5
Temperature Monitor
2.12.5.1
Thermometers
2.12.5.2
Thermocouples
2.12.5.3
Resistance Temperature Detectors (RTDs)
2.12.5.4
Thermowells
2.12.6
Pressure Gages
2.12.6.1
Panel Gages
2.12.6.2
Header Gages
2.12.6.3
Differential Gages
2.12.7
Level Elements
2.12.8
Flow Elements
2.12.9
Density Elements and Transmitters
2.12.10
Fly Ash Level Alarms
2.12.10.1
Hopper Level Signals
2.12.11
Transmitters
2.12.12
Limit Switches
2.12.13
Gage Glasses
2.12.14
Solenoid Valves
2.12.15
Sulfur Dioxide Analyzers
2.12.16
Factory Tests
2.12.17
Nameplates
2.13
STRUCTURAL AND MISCELLANEOUS STEEL
2.13.1
Girts and Opening Frames
2.13.2
Slide Bearings
2.13.3
Miscellaneous Steel
2.13.4
Fabrication
2.13.4.1
Grating
2.13.4.2
Stairs
2.13.5
Access
2.13.6
Personnel Access Requirements
2.13.6.1
Class 1
2.13.6.2
Class 2
2.13.6.3
Class 3
2.13.6.4
Maintenance Access Requirements
2.13.7
Painting
PART 3
EXECUTION
3.1
INSPECTION
3.1.1
Contractor Construction Representatives
3.1.2
Contractor Construction Representative Areas of Work
3.1.3
Field Service Engineer Representatives
3.2
INSULATION INSTALLATION
3.2.1
General
3.2.2
Block and Mineral Fiberboard Insulation Installation
3.2.3
Mineral Fiber Blanket Insulation Installation
SECTION 23 51 43.00 20
Page 4
3.2.4
Protection From Insulation Materials
3.3
CASING INSTALLATION
3.3.1
Structural Steel Grid System
3.3.2
Access Openings
3.3.3
Weatherproofing
3.3.4
Convection Stops
3.3.5
Casing Attachment
3.4
FIELD INSPECTIONS AND TESTS
3.4.1
General
3.4.2
Hydrostatic Tests
3.4.3
Smoke Tests
3.4.4
Acceptance Tests
3.4.5
System Stoichiometry Tests
3.4.6
System Power Consumption Tests
3.4.7
Test Failures
3.5
PAINTING
3.5.1
Galvanic Corrosion Prevention
3.6
SCHEDULE
-- End of Section Table of Contents --
SECTION 23 51 43.00 20
Page 5
PART 1
1.1
GENERAL
REFERENCES
**************************************************************************
NOTE: This paragraph is used to list the
publications cited in the text of the guide
specification. The publications are referred to in
the text by basic designation only and listed in
this paragraph by organization, designation, date,
and title.
Use the Reference Wizard's Check Reference feature
when you add a RID outside of the Section's
Reference Article to automatically place the
reference in the Reference Article. Also use the
Reference Wizard's Check Reference feature to update
the issue dates.
References not used in the text will automatically
be deleted from this section of the project
specification when you choose to reconcile
references in the publish print process.
**************************************************************************
The publications listed below form a part of this specification to the
extent referenced. The publications are referred to within the text by the
basic designation only.
ACOUSTICAL SOCIETY OF AMERICA (ASA)
ASA S12.54
(2011) Acoustics - Determination of Sound
Power Levels of Noise Sources Using Sound
Pressure - Engineering Method in an
Essentially Free Field over a Reflecting
Plane
AIR MOVEMENT AND CONTROL ASSOCIATION INTERNATIONAL (AMCA)
AMCA 201
(2002; R 2011) Fans and Systems
AMCA 210
(2007) Laboratory Methods of Testing Fans
for Aerodynamic Performance Rating
AMCA 500-D
(2012) Laboratory Methods of Testing
Dampers for Rating
AMCA 801
(2001; R 2008) Industrial Process/Power
Generation Fans: Specification Guidelines
AMCA 802
(2002; R 2008) Industrial Process/Power
Generation Fans: Establishing Performance
Using Laboratory Models
AMCA 99
(2010) Standards Handbook
AMERICAN BEARING MANUFACTURERS ASSOCIATION (ABMA)
ABMA 11
(2014) Load Ratings and Fatigue Life for
SECTION 23 51 43.00 20
Page 7
PART 1
1.1
GENERAL
REFERENCES
**************************************************************************
NOTE: This paragraph is used to list the
publications cited in the text of the guide
specification. The publications are referred to in
the text by basic designation only and listed in
this paragraph by organization, designation, date,
and title.
Use the Reference Wizard's Check Reference feature
when you add a RID outside of the Section's
Reference Article to automatically place the
reference in the Reference Article. Also use the
Reference Wizard's Check Reference feature to update
the issue dates.
References not used in the text will automatically
be deleted from this section of the project
specification when you choose to reconcile
references in the publish print process.
**************************************************************************
The publications listed below form a part of this specification to the
extent referenced. The publications are referred to within the text by the
basic designation only.
ACOUSTICAL SOCIETY OF AMERICA (ASA)
ASA S12.54
(2011) Acoustics - Determination of Sound
Power Levels of Noise Sources Using Sound
Pressure - Engineering Method in an
Essentially Free Field over a Reflecting
Plane
AIR MOVEMENT AND CONTROL ASSOCIATION INTERNATIONAL (AMCA)
AMCA 201
(2002; R 2011) Fans and Systems
AMCA 210
(2007) Laboratory Methods of Testing Fans
for Aerodynamic Performance Rating
AMCA 500-D
(2012) Laboratory Methods of Testing
Dampers for Rating
AMCA 801
(2001; R 2008) Industrial Process/Power
Generation Fans: Specification Guidelines
AMCA 802
(2002; R 2008) Industrial Process/Power
Generation Fans: Establishing Performance
Using Laboratory Models
AMCA 99
(2010) Standards Handbook
AMERICAN BEARING MANUFACTURERS ASSOCIATION (ABMA)
ABMA 11
(2014) Load Ratings and Fatigue Life for
SECTION 23 51 43.00 20
Page 7
Roller Bearings
ABMA 9
(2015) Load Ratings and Fatigue Life for
Ball Bearings
AMERICAN INSTITUTE OF STEEL CONSTRUCTION (AISC)
AISC 360
(2010) Specification for Structural Steel
Buildings
AMERICAN WELDING SOCIETY (AWS)
AWS D1.1/D1.1M
(2015) Structural Welding Code - Steel
ASME INTERNATIONAL (ASME)
ASME B16.3
(2011) Malleable Iron Threaded Fittings,
Classes 150 and 300
ASME B16.5
(2013) Pipe Flanges and Flanged Fittings:
NPS 1/2 Through NPS 24 Metric/Inch Standard
ASME B16.9
(2012) Standard for Factory-Made Wrought
Steel Buttwelding Fittings
ASME B31.1
(2014; INT 1-47) Power Piping
ASME B36.10M
(2015) Standard for Welded and Seamless
Wrought Steel Pipe
ASME BPVC
(2010) Boiler and Pressure Vessels Code
ASME HST-4
(1999; R 2010) Performance Standard for
Overhead Electric Wire Rope Hoists
ASTM INTERNATIONAL (ASTM)
ASTM A106/A106M
(2014) Standard Specification for Seamless
Carbon Steel Pipe for High-Temperature
Service
ASTM A108
(2013) Standard Specification for Steel
Bar, Carbon and Alloy, Cold-Finished
ASTM A123/A123M
(2013) Standard Specification for Zinc
(Hot-Dip Galvanized) Coatings on Iron and
Steel Products
ASTM A126
(2004; R 2014) Standard Specification for
Gray Iron Castings for Valves, Flanges,
and Pipe Fittings
ASTM A167
(2011) Standard Specification for
Stainless and Heat-Resisting
Chromium-Nickel Steel Plate, Sheet, and
Strip
ASTM A240/A240M
(2015b) Standard Specification for
Chromium and Chromium-Nickel Stainless
SECTION 23 51 43.00 20
Page 8
Steel Plate, Sheet, and Strip for Pressure
Vessels and for General Applications
ASTM A242/A242M
(2013) Standard Specification for
High-Strength Low-Alloy Structural Steel
ASTM A269/A269M
(2015a) Standard Specification for
Seamless and Welded Austenitic Stainless
Steel Tubing for General Service
ASTM A276/A276M
(2015) Standard Specification for
Stainless Steel Bars and Shapes
ASTM A307
(2014) Standard Specification for Carbon
Steel Bolts and Studs, 60 000 PSI Tensile
Strength
ASTM A325
(2014) Standard Specification for
Structural Bolts, Steel, Heat Treated,
120/105 ksi Minimum Tensile Strength
ASTM A325M
(2014) Standard Specification for
Structural Bolts, Steel, Heat Treated, 830
MPa Minimum Tensile Strength (Metric)
ASTM A36/A36M
(2014) Standard Specification for Carbon
Structural Steel
ASTM A48/A48M
(2003; R 2012) Standard Specification for
Gray Iron Castings
ASTM A490
(2014a) Standard Specification for
Structural Bolts, Alloy Steel, Heat
Treated, 150 ksi Minimum Tensile Strength
ASTM A490M
(2014a) Standard Specification for
High-Strength Steel Bolts, Classes 10.9
and 10.9.3, for Structural Steel Joints
(Metric)
ASTM A53/A53M
(2012) Standard Specification for Pipe,
Steel, Black and Hot-Dipped, Zinc-Coated,
Welded and Seamless
ASTM A580/A580M
(2015) Standard Specification for
Stainless Steel Wire
ASTM A743/A743M
(2013a; E 2014) Standard Specification for
Castings, Iron-Chromium,
Iron-Chromium-Nickel, Corrosion Resistant,
for General Application
ASTM B103/B103M
(2015) Standard Specification for Phosphor
Bronze Plate, Sheet, Strip, and Rolled Bar
ASTM B443
(2000; R 2014) Standard Specification for
Nickel-Chromium-Molybdenum-Columbium Alloy
(UNS N06625)and
Nickel-Chromium-Molybdenum-Silicon Alloy
SECTION 23 51 43.00 20
Page 9
(UNS N06219)* Plate, Sheet, and Strip
ASTM B584
(2014) Standard Specification for Copper
Alloy Sand Castings for General
Applications
ASTM B61
(2015) Standard Specification for Steam or
Valve Bronze Castings
ASTM B75/B75M
(2011) Standard Specification for Seamless
Copper Tube
ASTM C110
( 2015) Standard Test Methods for
Physical Testing of Quicklime, Hydrated
Lime, and Limestone
ASTM C25
(2011; E 2014) Standard Test Method for
Chemical Analysis of Limestone, Quicklime,
and Hydrated Lime
ASTM D1682
(1964; R 1975e1) Test for Breaking Load
and Elongation of Textile Fabrics
ASTM D1777
(1996; E 2011; R 2011) Thickness of
Textile Materials
ASTM D2176
(1997a; R 2007) Folding Endurance of Paper
by the M.I.T. Tester
ASTM D3775
(2012) Warp End Count and Filling Pick
Count of Woven Fabric
ASTM D3776/D3776M
(2009a; R 2013) Standard Test Method for
Mass Per Unit Area (Weight) of Fabric
ASTM D3887
(1996; R 2008) Standard Specification for
Tolerances for Knitted Fabrics
ASTM D396
(2015b) Standard Specification for Fuel
Oils
ASTM D578/D578M
(2005; E 2011; R 2011) Glass Fiber Strands
ASTM D737
(2004; R 2012) Air Permeability of Textile
Fabrics
ASTM E515
(2011) Leaks Using Bubble Emission
Techniques
HYDRAULIC INSTITUTE (HI)
HI M100
(2009) HI Pump Standards Set
INSTITUTE OF CLEAN AIR COMPANIES (ICAC)
ICAC EP-7
(2004) Electrostatic Precipitator Gas Flow
Model Studies
ICAC F-2
(1972) Fundamentals of Fabric Collectors
SECTION 23 51 43.00 20
Page 10
and Glossary of Terms
ICAC F-3
(2002) Operation and Maintenance of Fabric
Filters
ICAC F-5
(1991) Types of Fabric Filters
INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS (IEEE)
IEEE 112
(2004) Standard Test Procedure for
Polyphase Induction Motors and Generators
IEEE 114
(2001) Test Procedure for Single-Phase
Induction Motors
IEEE 85
(1973; R 1986) Test Procedure for Airborne
Sound Measurements on Rotating Electric
Machinery
IEEE C37.90.1
(2013) Standard for Surge Withstand
Capability (SWC) Tests for Relays and
Relay Systems Associated with Electric
Power Apparatus
MANUFACTURERS STANDARDIZATION SOCIETY OF THE VALVE AND FITTINGS
INDUSTRY (MSS)
MSS SP-58
(1993; Reaffirmed 2010) Pipe Hangers and
Supports - Materials, Design and
Manufacture, Selection, Application, and
Installation
MSS SP-69
(2003; Notice 2012) Pipe Hangers and
Supports - Selection and Application (ANSI
Approved American National Standard)
MATERIAL HANDLING INDUSTRY OF AMERICA (MHI)
MHI MH27.1
(2009) Specifications for Underhung Cranes
and Monorail Systems
NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)
NEMA AB 1
(2002) Molded-Case Circuit Breakers,
Molded Case Switches, and Circuit-Breaker
Enclosures
NEMA C50.41
(2012) American National Standard for
Polyphase Induction Motors for Power
Generating Stations
NEMA ICS 6
(1993; R 2011) Enclosures
NEMA MG 1
(2014) Motors and Generators
NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)
NFPA 70
(2014; AMD 1 2013; Errata 1 2013; AMD 2
2013; Errata 2 2013; AMD 3 2014; Errata
SECTION 23 51 43.00 20
Page 11
dimensional stability. Submit detailed specifications of any rubber hose
and rubber-lined pipe proposed for use. For electric motors, submit
nameplate data for motors including the manufacturer's name, model, serial
number, type and frame designation, power horsepower rating, and time
rating. For fans, provide octave band sound pressure levels, fan
performance curves, class, air flow, pressure, power horsepower, and
efficiency. For draft equipment, submit certified performance data
including performance curves showing flow vs. head, efficiency and brake
power horsepower from zero flow to at least 120 percent of maximum design
flow.
1.5
1.5.1
QUALITY ASSURANCE
Manufacturer Experience
**************************************************************************
NOTE: Contractor equipment used for experience
requirements shall be at least as efficient as local
or state percent sulfur dioxide removal regulations.
**************************************************************************
The Contractor shall have successfully met air pollution emission
requirements on two coal-fired boilers each with a minimum of 4719 L/s
10,000-actual cubic feet per minute (acfm) or larger similar spray dryer
sulfur dioxide absorber and fabric filter baghouse systems. The completed
system shall have utilized lime slurry as the absorbent material. Slurry
atomization shall have been by rotary atomization or by two-fluid nozzle
atomization. The completed system spray dryer sulfur dioxide absorber shall
have been designed for and operated at inlet flue gas temperatures of 177
degrees C 350 degrees F or less, and shall have achieved at least [_____]
percent sulfur dioxide removal including sulfur dioxide removal in the
baghouse during performance testing. The Contractor shall have also
successfully met air pollution emission requirements at least five fabric
filter baghouse installations of a size comparable to or larger than that
[proposed][bid]. At least two of the five installations shall have been a
fly ash application and at least two of the five shall have utilized the
pulse jet cleaning method. The Contractor shall also have provided at
least one dry FGD system on a coal-fired boiler that has been utilizing a
spray dryer sulfur dioxide absorber and a fabric filter baghouse is in
operation at least 24 months prior to the close of bid date for the
proposed system. The previous commercial system shall have the following
design features in common with the system to be provided under this
contract:
a.
Lime slurry preparation system including storage bin and lime slaker;
b.
Rotary atomization, or two-fluid nozzle atomization using compressed
air;
c.
Spray dryer design inlet temperature of 177 degrees C 350 degrees F or
lower; and
**************************************************************************
NOTE: 80 to 85 percent sulfur dioxide removal is
possible with most commercial units. Negotiate with
most commercial units. Negotiate with state and
local air pollution authorities prior to bidding
emission trading should be utilized. Emission
trading includes trading, off-sets, and banking.
SECTION 23 51 43.00 20
Page 16
Ensure that any reductions in emissions are banked
for future use or sale.
**************************************************************************
d.
Minimum [_____] percent sulfur dioxide removal over a gas flow range of
30 percent to 100 percent of design gas flow. Process control system
used and instrumentation provided shall be the same as those in
applications at pilot plant or commercial installations use for
qualifying experience.
1.5.1.1
Auxiliary Manufacturer Experience
The lime slurry individual equipment may be the manufacturer's standard,
but the particular combination of that equipment into a lime slurry
preparation system shall have a history of successful and reliable
operation for a period of at least three years. Mechanical draft equipment
and appurtenances and ductwork and expansion joint equipment and materials
shall have an acceptable history of satisfactory reliable operation in
industrial steam plant use for a period of at least three years at
comparable temperature, pressure, voltage, and design stress levels. The
Contractor shall provide information necessary to demonstrate history of
operation.
1.5.2
Certificates
1.5.2.1
Pipe Welding Procedures
Submit the welding procedures and the heat treatment records for pipe
fabrication.
1.5.2.2
Weld Testing Procedures
Describe procedures for nondestructive testing which shall be performed on
the welds or base material of the fans.
1.5.2.3
Welding Shops
Submit certification that welding shops are qualified as specified.
1.5.2.4
Qualifying Experience Certification
Submit proof that the dust collector manufacturer has installed the
following systems:
a.
Spray dryer system
b.
Lime slurry system
c.
Mechanical draft equipment
d.
Fabric filter baghouse
e.
Dry FGD systems
Manufacturer shall certify that no failures have occurred on this type
collector built by the manufacturer within 5 years preceding contract award
date, as required by paragraph entitled "Certification."
SECTION 23 51 43.00 20
Page 17
**************************************************************************
**************************************************************************
NOTE: Test model system scale shall meet good
engineering practices. In no case shall scale be
less than 1:100 1/8 scale.
**************************************************************************
**************************************************************************
NOTE: Dust used for testing shall be sifted,
bleached wheat flour or approved vendor selection.
**************************************************************************
Conduct a three-dimensional model study as defined in ICAC EP-7 to verify
air flow design of the spray dryer sulfur dioxide absorbers, ductwork,
fabric filter baghouse, and inlet transition to stack and to determine the
flow distribution and requirements for distribution devices to provide
adequate operating conditions in all of the equipment. The model study
shall be used by the Contractor to determine flow distribution and pressure
drop through out the system. Make necessary modifications to the model to
minimize pressure drop in ductwork. The scope of the model study shall
begin at the [economizer][air heater] outlets and end in the inlet
transition to the stack. Model shall represent the complete system, as
specified, reduced to not less than 1:100 1/8 scale. Test model shall have
dimensional tolerance of plus or minus 1 1/2 mm 1/16 inch. Dynamic and
geometric similitude shall be observed in all phases of the model study.
Flow conditions in the spray dryer sulfur dioxide absorbers, fabric filter
baghouse, ductwork, and inlet transition to the stack shall be tested and
the results submitted to the Contracting Officer. Flow and dust
distribution tests shall be performed at 30 percent, 50 percent, 75
percent, 100 percent, and 125 percent of maximum continuous flow rating.
The Contractor shall notify the Contracting Officer no less than 15 working
days before the tests are scheduled to be made so that Contracting Officer
may witness test. Dust used for testing shall be [_____].
1.5.6
Tabulations
Submit a tabulation of piping connections with each assigned a unique
designation including size and type of each connection in all views. Submit
a tabulation of valves furnished, with each assigned a unique designation
including manufacturer, pressure and temperature rating, body material,
trim material, and manufacturer's model or figure number, and a detailed
cross section of each different model or figure number, and valve. Submit a
tabulation of instruments and instrument connections furnished in spray
dryer sulfur dioxide absorbers, fabric filter baghouse, ductwork, and
auxiliary equipment. Assign a unique alphanumeric designation and show
type, location, and quantity for each connection.
1.6
SUBMITTALS
**************************************************************************
NOTE: Review Submittal Description (SD) definitions
in Section 01 33 00 SUBMITTAL PROCEDURES and edit
the following list to reflect only the submittals
required for the project.
The Guide Specification technical editors have
designated those items that require Government
approval, due to their complexity or criticality,
SECTION 23 51 43.00 20
Page 20
with a "G". Generally, other submittal items can be
reviewed by the Contractor's Quality Control
System.
Only add a “G” to an item, if the
submittal is sufficiently important or complex in
context of the project.
For submittals requiring Government approval on Army
projects, a code of up to three characters within
the submittal tags may be used following the "G"
designation to indicate the approving authority.
Codes for Army projects using the Resident
Management System (RMS) are: "AE" for
Architect-Engineer; "DO" for District Office
(Engineering Division or other organization in the
District Office); "AO" for Area Office; "RO" for
Resident Office; and "PO" for Project Office. Codes
following the "G" typically are not used for Navy,
Air Force, and NASA projects.
An "S" following a submittal item indicates that the
submittal is required for the Sustainability
Notebook to fulfill federally mandated sustainable
requirements in accordance with Section 01 33 29
SUSTAINABILITY REPORTING.
Choose the first bracketed item for Navy, Air Force
and NASA projects, or choose the second bracketed
item for Army projects.
**************************************************************************
Government approval is required for submittals with a "G" designation;
submittals not having a "G" designation are [for Contractor Quality Control
approval.][for information only. When used, a designation following the
"G" designation identifies the office that will review the submittal for
the Government.] Submittals with an "S" are for inclusion in the
Sustainability Notebook, in conformance to Section 01 33 29 SUSTAINABILITY
REPORTING. Submit the following in accordance with Section 01 33 00
SUBMITTAL PROCEDURES:
SD-01 Preconstruction Submittals
Tabulation of piping connections
Tabulation of valves
Instruments and instrument connections
SD-02 Shop Drawings
Dust collector system
Dust collector components
Piping drawings
Wiring diagrams
Schematic control diagrams
SECTION 23 51 43.00 20
Page 21
dimensional stability. Submit detailed specifications of any rubber hose
and rubber-lined pipe proposed for use. For electric motors, submit
nameplate data for motors including the manufacturer's name, model, serial
number, type and frame designation, power horsepower rating, and time
rating. For fans, provide octave band sound pressure levels, fan
performance curves, class, air flow, pressure, power horsepower, and
efficiency. For draft equipment, submit certified performance data
including performance curves showing flow vs. head, efficiency and brake
power horsepower from zero flow to at least 120 percent of maximum design
flow.
1.5
1.5.1
QUALITY ASSURANCE
Manufacturer Experience
**************************************************************************
NOTE: Contractor equipment used for experience
requirements shall be at least as efficient as local
or state percent sulfur dioxide removal regulations.
**************************************************************************
The Contractor shall have successfully met air pollution emission
requirements on two coal-fired boilers each with a minimum of 4719 L/s
10,000-actual cubic feet per minute (acfm) or larger similar spray dryer
sulfur dioxide absorber and fabric filter baghouse systems. The completed
system shall have utilized lime slurry as the absorbent material. Slurry
atomization shall have been by rotary atomization or by two-fluid nozzle
atomization. The completed system spray dryer sulfur dioxide absorber shall
have been designed for and operated at inlet flue gas temperatures of 177
degrees C 350 degrees F or less, and shall have achieved at least [_____]
percent sulfur dioxide removal including sulfur dioxide removal in the
baghouse during performance testing. The Contractor shall have also
successfully met air pollution emission requirements at least five fabric
filter baghouse installations of a size comparable to or larger than that
[proposed][bid]. At least two of the five installations shall have been a
fly ash application and at least two of the five shall have utilized the
pulse jet cleaning method. The Contractor shall also have provided at
least one dry FGD system on a coal-fired boiler that has been utilizing a
spray dryer sulfur dioxide absorber and a fabric filter baghouse is in
operation at least 24 months prior to the close of bid date for the
proposed system. The previous commercial system shall have the following
design features in common with the system to be provided under this
contract:
a.
Lime slurry preparation system including storage bin and lime slaker;
b.
Rotary atomization, or two-fluid nozzle atomization using compressed
air;
c.
Spray dryer design inlet temperature of 177 degrees C 350 degrees F or
lower; and
**************************************************************************
NOTE: 80 to 85 percent sulfur dioxide removal is
possible with most commercial units. Negotiate with
most commercial units. Negotiate with state and
local air pollution authorities prior to bidding
emission trading should be utilized. Emission
trading includes trading, off-sets, and banking.
SECTION 23 51 43.00 20
Page 16
Ensure that any reductions in emissions are banked
for future use or sale.
**************************************************************************
d.
Minimum [_____] percent sulfur dioxide removal over a gas flow range of
30 percent to 100 percent of design gas flow. Process control system
used and instrumentation provided shall be the same as those in
applications at pilot plant or commercial installations use for
qualifying experience.
1.5.1.1
Auxiliary Manufacturer Experience
The lime slurry individual equipment may be the manufacturer's standard,
but the particular combination of that equipment into a lime slurry
preparation system shall have a history of successful and reliable
operation for a period of at least three years. Mechanical draft equipment
and appurtenances and ductwork and expansion joint equipment and materials
shall have an acceptable history of satisfactory reliable operation in
industrial steam plant use for a period of at least three years at
comparable temperature, pressure, voltage, and design stress levels. The
Contractor shall provide information necessary to demonstrate history of
operation.
1.5.2
Certificates
1.5.2.1
Pipe Welding Procedures
Submit the welding procedures and the heat treatment records for pipe
fabrication.
1.5.2.2
Weld Testing Procedures
Describe procedures for nondestructive testing which shall be performed on
the welds or base material of the fans.
1.5.2.3
Welding Shops
Submit certification that welding shops are qualified as specified.
1.5.2.4
Qualifying Experience Certification
Submit proof that the dust collector manufacturer has installed the
following systems:
a.
Spray dryer system
b.
Lime slurry system
c.
Mechanical draft equipment
d.
Fabric filter baghouse
e.
Dry FGD systems
Manufacturer shall certify that no failures have occurred on this type
collector built by the manufacturer within 5 years preceding contract award
date, as required by paragraph entitled "Certification."
SECTION 23 51 43.00 20
Page 17
1.5.2.5
Factory Test Certification
Submit certificates of completion of factory tests of mechanical draft
equipment.
1.5.2.6
Dry FGD System Experience Certification
Indicate compliance with paragraph entitled "Quality Assurance." Submit a
listing of other applications of the [proposed] [bid] dry scrubber system
within the range of 4719 to 47,190 L/s 10,000 to 100,000 acfm and shall
have demonstrated operation for 8,000 hours. Include a narrative
description of the specific design changes which must be made to apply
application experience to dry flue gas desulfurization (FGD) systems.
Specifically note the use of the completed dry FGD system test results to
verify the feasibility of the design changes. Information to be contained
in the certificate shall include:
a.
List of at least two installations meeting the requirements set forth
in the paragraph entitled "Manufacturer Experience."
b.
Owner and location of each such installation including name of contact,
address, and telephone number.
c.
Design inlet gas volume, actual liter per second cubic feet per minute;
inlet gas temperature, degrees C degrees F; inlet dust loading, grams
per liter grains per acf; outlet dust loading; grams per liter grains
per acf; and dry FGD system model number.
d.
Type of coal-fired boiler.
e.
Description of fabric filter bag material and cleaning mechanism.
f.
Completed bid forms for dry FGD systems.
1.5.3
Test Reports
1.5.3.1
Pump Tests Reports
Include certified curves showing pump performances.
1.5.3.2
Damper Tests Reports
In each damper factory test report, report, discuss the test conditions,
results, defects found and corrective action taken. In lieu of factory
tests on poppet dampers, include the results of field tests performed on
similar installations.
1.5.3.3
Dust Collector Model Tests Report
Submit model test reports within 30 days of test completion. The test
reports shall include a scale drawing of the model showing actual
dimensions and a scale drawing of the full-size installation showing
modifications made and devices added to the ductwork and transitions as a
result of the model study. The test report shall also include uniform gas
velocity diagrams and histograms, indicating the root mean square velocity
deviation, standard deviations, and mean velocity, at strategic locations
which shall include, but not be limited to the following:
a.
Inlet to spray dryer sulfur dioxide absorbers.
SECTION 23 51 43.00 20
Page 18
b.
Inlet to baghouse.
c.
Inlet to each fabric filter baghouse module.
d.
Inlets to induced draft fans.
e.
Stack inlet.
f.
Two stack diameters located downstream of the stack inlet.
Submit a complete explanation of the test procedures including flow rates,
pressures, sample calculations and assumptions prior to testing. Deviations
in dynamic or geometric similitude by the model from the full-size
installation shall be listed and justified. Conclusions that show type and
location of devices required for proper gas distribution and modifications
necessary to the proposed ductwork, that result from model testing, shall
be incorporated into the Contractor's final ductwork design. The report
should recommend the location of test ports, the location and type of flow
distribution devices in stack, and the location of gas flow instrumentation
points and monitors. Provide a complete listing of pressure drop data
taken at each pressure tap during each test run and also include data from
runs before and after the addition of supplemental flow distribution
devices that correct distribution problems identified by initial runs.
Pressure taps shall be located as required to accurately determine the
pressure drop across critical ductwork components and the effect of the
additional distribution devices on the pressure drop. Submit with the
report a complete set of photographs and videotapes recordings of model
during air flow test.
1.5.3.4
Instrument Calibration and Testing
For instrument calibration and testing, certify that instruments were
calibrated and testing readings indicated are true, that computations
required for testing are accurate, that acceptable methods were used, and
that the equipment satisfactorily performed in accordance with the
requirements.
1.5.4
Records
Submit text of each required posted operating instructions. For device
purchase information, submit data or specification sheets for each device
furnished by this contract. These sheets shall be the actual sheets used
for ordering and fabrication, and shall include the final vendor's own
sheets, where applicable, in addition to the Contractor's purchase order
forms. Provide an index for the data sheets. These sheets shall include
technical data for the devices including tag number, manufacturer, complete
catalog or model number, scale range, complete electrical information
including current voltage ratings, contact action (SPST, DPDT, etc.), data
or specification sheet number, scheduling information showing dates for
ordering, fabrication, shipment, etc., manufacturer's data for tubing,
fittings, valves and accessories, and material.
1.5.5
Model Test
**************************************************************************
NOTE: Contracting Officer shall have authority to
select an experienced modeller from list supplied by
contractor.
SECTION 23 51 43.00 20
Page 19
items are listed for the convenience of the Contractor in understanding the
scope of supply.
2.2.1
Spray Dryer Sulfur Dioxide Absorbers
**************************************************************************
NOTE: Air compressor is specified in paragraph
entitled "Two-Fluid Nozzle Atomizers."
**************************************************************************
Provide spray dryer sulfur dioxide absorbers, complete with slurry
atomizers, inlet gas dispersers, conveying system for continuous removal of
absorber products, absorber product holding bin(s), frames for penthouse
and hopper enclosures, mechanism for atomizer removal, and spare atomizers.
For systems utilizing two-fluid nozzle atomizers, provide a dedicated air
compressor system to provide air for slurry atomization.
2.2.2
Fabric Filter Baghouse
Provide fabric filter baghouses, complete with inlet and outlet manifolds,
pulse jet or reverse gas cleaning systems, bags, bag attachment and support
hardware, and frames for penthouse and hopper level enclosures.
2.2.3
Lime Slurry Preparation System
Provide lime slurry preparation system including lime feed bin, fill pipe
and truck unloading connection, bin vent filter, bin vibrators, lime
feeders, slakers, grit removal equipment, slaker product tank, agitators,
and drives. Provide accessory equipment and control panels to control lime
slurry preparation system. Provide tanks as required by specific system
design including slurry mixing tanks, feed tanks, and head tanks.
2.2.4
Pumps, Valves, and Motors
Provide pumps including slurry feed pumps and process water pumps. Provide
sump pumps as required as a result of the specific system design. Provide
water, slurry and air piping (excluding field-installed instrument air
tubing), piping support systems, valves, and expansion joints required for
the FGD system within the battery limits indicated. Provide electric
motors for induced draft fans, pumps, and other equipment included in this
system. Provide motor control centers as required for motors furnished
under this contract rated at 480 volts and less. Provide separate motor
control centers for each spray dryer absorber-baghouse unit, and for the
lime slurry preparation system, complete with internal controls wired and
interlocked together and brought out to terminal blocks for remote field
connection by the Contractor.
2.2.5
Ductwork and Draft Equipment
Provide induced draft fans including inlet boxes, dampers, and drives.
Provide ductwork between [economizer][air heater] outlet interfaces and
stack inlet including spray dryer absorber bypass reheat ducts, as
necessary. Provide test ports. Provide expansion joints, turning vanes,
dampers, damper operators, and seal air systems including fabric filter
baghouse dampers. Provide gas distribution devices in ductwork ahead of
baghouse to assure even flow of gases into baghouse.
SECTION 23 51 43.00 20
Page 28
Parameter
Season
Temperature (Degrees F)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Wet Bulb
Jun-Sep
[_____]
[_____]
**************************************************************************
Contractor shall use site conditions of elevation, design ambient
temperature, and design dry and wet bulb temperature, and duration
(differentiate for different seasons including frequency of occurrence of
higher temperatures) specified.
2.5
OPERATING INSTRUCTIONS
2.5.1
Steam Generators
**************************************************************************
NOTE: Insert appropriate Section number and title
in the blanks below using format per UFC 1-300-02.
**************************************************************************
The system shall be designed for operation with [the boiler(s) specified in
[_____]] [boiler(s) manufactured by [_____], Type [_____], Model No.
[_____]]. The steam generator is [a new] [an existing] [pulverized
coal-fired] [spreader stoker-fired] [underfeed stoker-fired] boiler.
Operating conditions for each steam generator at its maximum rating are:
a.
Type firing [_____]
b.
Steam flow, kg/s lb/hr [_____]
c.
Steam pressure, kPa (gage) psig [_____]
d.
Steam temperature, degrees C degrees F [_____]
e.
Gross heat input, kW 106 Btu/hr [_____]
f.
Excess air leaving boiler, percent [_____]
g.
Grade elevation, meters feet above mean sea level [_____]
For purposes of the proposal, the Contractor shall assume that the gross
heat input at any fractional load rating is that same fraction of the
maximum rated heat input given above.
2.5.2
Fuels
The steam generator shall utilize a fuel with following properties:
Coal:
SECTION 23 51 43.00 20
Page 30
**************************************************************************
NOTE: Coal sources vary year to year when purchased
by Defense Fuel Supply Agency (DFSA). Request a
contract for a longer period of time. Specified
coal properties shall be maintained throughout
length of contract.
**************************************************************************
a.
Source:
State
[_____]
Seam
[_____]
Area
[_____]
b.
Proximate Analysis-- Percent (as received)
Average
Moisture
Volatile Matter
Fixed Carbon
Ash
Higher Heating Value, kJ/kg Btu/lb
c.
Ultimate Analysis--Percent (as received)
Moisture
Carbon
Hydrogen
Nitrogen
Chlorine
Sulfur
Ash
Oxygen (by Difference)
Total
d.
Mineral Analysis of Ash-- Percent
Phosphorus Pentoxide, P205
SECTION 23 51 43.00 20
Page 31
Range
SD-06 Test Reports
Lime system component equipment
Instrumentation and control devices
Atomizers
Piping
Pump tests
Bag material
Fans
Motors
Damper tests
Mechanical draft equipment
Instrumentation and control devices
Dust collector model tests
Smoke tests
System stoichiometry tests
System power consumption tests
Instrument calibration and testing
Include field data sheets and show the calculation of
stoichiometry with stoichiometry field test report. Include an
explanation of the method used for the system power consumption
determination.
SD-07 Certificates
Pipe welding procedures
Weld testing procedures
Welding shops
Qualifying experience certification
Dry FGD system experience certification
Factory test certification
SD-10 Operation and Maintenance Data
Atomizers, Data Package 3
Fans, Data Package 2
SECTION 23 51 43.00 20
Page 23
Lime system component equipment, Data Package 2
Pumps, Data Package 2
Valves, Data Package 2
Dampers, Data Package 2
Motors, Data Package 2
Fabric filter baghouse, Data Package 2
Instrumentation and control devices, Data Package 3
Submit in accordance with Section 01 78 23 OPERATION AND
MAINTENANCE DATA. Include the manufacturer's recommended supply
list for each type of instrumentation recorder furnished. The
lists shall include as minimum information, the chart paper type,
size, and order number, ink type (cartridge or pen) order number,
capillary tube order number, and pen point order number.
SD-11 Closeout Submittals
Device purchase information
Posted operating instructions
1.7
DELIVERY AND STORAGE
Equipment shall be shipped factory assembled, except when the physical
size, arrangement, or configuration of the equipment, or shipping
limitations, makes the shipment of assembled equipment impracticable.
1.8
AMBIENT ENVIRONMENTAL REQUIREMENTS
**************************************************************************
NOTE: Insert extreme temperatures experienced at
site. Do not use heating or cooling design
conditions.
**************************************************************************
The dry FGD system design shall be such that the electrical equipment shall
perform satisfactorily in the ambient environment of [_____] to [_____]
degrees C degrees F and [_____] to [_____] percent relative humidity.
1.9
1.9.1
EXPERIENCE CLAUSE
Certificate
**************************************************************************
NOTE: Select air flows, temperatures, and dust
loadings similar to design conditions.
**************************************************************************
Units which have been replaced within 3 years of start-up, have had
retrofit, overhaul, or repair cost exceeding 10 percent of the original
price of the collector (excluding transportation and erection), have failed
to meet specified removal efficiency, or have allowed emissions to exceed
SECTION 23 51 43.00 20
Page 24
specified limits shall be considered failures. Off-line time exceeding
five percent of the planned annual operation or 300 hours per annum,
whichever is less, within the first 3 years of operation due to collector
or component failure shall be considered a failure. System failure due to
natural disaster or a result of damage from fire or explosion in
appurtenant structures will not be considered failure. Pilot or research
projects will be excluded from failure analysis. The certificate must
certify that the manufacturer has constructed not less than two dry FGD
systems of the same design as proposed for this project treating flue gas
from a boiler with [automatic][manual] combustion control [and a mechanical
cyclone-type dust collector]. Each dry FGD system shall have performed
satisfactorily, normal maintenance or downtime of the associated
[boiler][dust collector] included, for a period of not less than 2 years
treating at least [_____] L/s acfm of inlet gas at a temperature of at
least [_____] degrees C degrees F, with inlet dust loading of at least
[_____] grams per liter grains per acf and outlet dust loading of at most
[_____] grams per actual liter grains per actual cubic feet. In
determining this experience:
a.
Only collection of fly ash as produced by [pulverized coal-fired
boilers] [stroker coal-fired boilers] is considered as equivalent
experience.
b.
Only experience at the maximum continuous flow rate, plus or minus 40
percent, maximum continuous inlet flue gas temperature, plus or minus
46 degrees C 50 degrees F, and maximum continuous inlet dust loading,
plus or minus 50 percent, is acceptable.
1.10
OPERATOR TRAINING PROGRAM
Provide an organized training program for the Government's operating
personnel including the system specified herein. The purpose of the
training program is to familiarize personnel with the operation and
maintenance of the flue gas cleaning system and the individual equipment
components. The training program shall be designed to provide the
operators with a working knowledge of the theory and principles of
operation of the system, the activities required for operation and control
of the system and the tools and techniques required for maintenance of the
system. The training program shall provide classroom instruction, testing,
and hands-on training to ensure that operators who complete the organized
program will be able to operate and maintain the flue gas cleaning system
for the Government. Furthermore, the training manuals and testing
materials shall provide information so that, in conjunction with the
operation and maintenance manuals furnished under this contract, future
training of new operators can be accomplished without the assistance of the
Contractor.
1.10.1
Training Manuals
Provide training manuals covering the complete FGD system and including
separate sections devoted to each major equipment item including spray
dryer sulfur dioxide absorbers, fabric filter baghouses, lime system,
induced draft fans, and system control panel. Each section shall include
equipment description, principles of operation, control philosophy, control
hardware, and relation to other equipment. Furnish [_____] copies and an
original of the complete training manual.
SECTION 23 51 43.00 20
Page 25
1.10.2
Testing Program
Furnish a written testing program designed to objectively determine the
individual level of comprehension of the material presented in the training
program to the participants. Use the testing program in conjunction with
the classroom instruction. Provide [_____] copies of the complete testing
program.
1.10.3
Classroom Instruction
Develop and present 40-hour course of organized classroom instruction by
experienced engineers. The classroom instruction shall cover theory and
principle of operation and shall utilize and augment the information
provided in the training manuals. Administrate the testing program at the
conclusion of the course. Present the course at least twice in order to
accommodate Government operating personnel. The Contractor shall arrange
with the Contracting Officer for classroom space and times for the classes
to be given.
1.10.4
Field Instructions
Service engineer shall provide 8-hour per day supervision of the system for
a period of 30 days after start-up to assist and instruct Government's
operations. Instruction shall include, but not be limited to the following:
a.
Actual start-up and shutdown of the FGD system for each boiler.
b.
Indoctrination to the lime handling system, stressing safety.
c.
Remove and install one atomizer.
d.
Disassemble and assemble one atomizer to the extent required for normal
maintenance.
e.
Review of instrument, gage, and control functions in the control room.
f.
Deliberate upset of FGD system and instruction on making necessary
corrections.
g.
Simulation of induced fan failure.
h.
Review of fabric filter baghouse maintenance including removal and
replacement of bags.
1.10.5
Video Recording
Furnish color video tapes made during field instruction or prepared color
video tapes covering the field instruction material. Video tapes
instruction and hands-on-training, along with prepared video instruction
tapes, shall become the property of the Government.
1.11
MODEL DELIVERY
The model shall remain the property of the Government, and shall be
delivered to the Government upon request by the Contracting Officer within
one year of start-up. The model shall include a support table as part of
the deliverable items.
SECTION 23 51 43.00 20
Page 26
Contractor.
2.6.5
Ductwork
**************************************************************************
NOTE: Ductwork velocities shall be such to maintain
self-cleaning conditions.
**************************************************************************
Ductwork upstream of the fabric filter baghouse outlets shall be designed
for a velocity of [_____] meter per second feet per minute at the design
flue gas flow, specified in paragraph entitled "Expected Flue Gas
Conditions." Ductwork downstream of the fabric filter baghouse outlets
shall be designed for a velocity of [_____] m/s fpm at the design flue gas
flow, specified in paragraph entitled "Expected Flue Gas Conditions."
Ductwork from the fabric filter baghouse outlet to the stack inlet shall be
designed to withstand a transient internal pressure (80 percent of yield
strength) range of minus 2490 Pa to plus 7470 Pa 10 inches Water Column
(WC) to plus 30 inches WC without permanent deformation of any structural
member at yield or in buckling.
2.6.6
Induced Draft Fans
**************************************************************************
NOTE: Pressures and air flows will be site specific
and will require system analysis.
**************************************************************************
**************************************************************************
NOTE: Dry and Wet Bulb Temperature and Duration:
Parameter
Season
Temperature (Degrees C)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Wet Bulb
Jun-Sep
[_____]
[_____]
Season
Temperature (Degrees F)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Parameter
SECTION 23 51 43.00 20
Page 37
items are listed for the convenience of the Contractor in understanding the
scope of supply.
2.2.1
Spray Dryer Sulfur Dioxide Absorbers
**************************************************************************
NOTE: Air compressor is specified in paragraph
entitled "Two-Fluid Nozzle Atomizers."
**************************************************************************
Provide spray dryer sulfur dioxide absorbers, complete with slurry
atomizers, inlet gas dispersers, conveying system for continuous removal of
absorber products, absorber product holding bin(s), frames for penthouse
and hopper enclosures, mechanism for atomizer removal, and spare atomizers.
For systems utilizing two-fluid nozzle atomizers, provide a dedicated air
compressor system to provide air for slurry atomization.
2.2.2
Fabric Filter Baghouse
Provide fabric filter baghouses, complete with inlet and outlet manifolds,
pulse jet or reverse gas cleaning systems, bags, bag attachment and support
hardware, and frames for penthouse and hopper level enclosures.
2.2.3
Lime Slurry Preparation System
Provide lime slurry preparation system including lime feed bin, fill pipe
and truck unloading connection, bin vent filter, bin vibrators, lime
feeders, slakers, grit removal equipment, slaker product tank, agitators,
and drives. Provide accessory equipment and control panels to control lime
slurry preparation system. Provide tanks as required by specific system
design including slurry mixing tanks, feed tanks, and head tanks.
2.2.4
Pumps, Valves, and Motors
Provide pumps including slurry feed pumps and process water pumps. Provide
sump pumps as required as a result of the specific system design. Provide
water, slurry and air piping (excluding field-installed instrument air
tubing), piping support systems, valves, and expansion joints required for
the FGD system within the battery limits indicated. Provide electric
motors for induced draft fans, pumps, and other equipment included in this
system. Provide motor control centers as required for motors furnished
under this contract rated at 480 volts and less. Provide separate motor
control centers for each spray dryer absorber-baghouse unit, and for the
lime slurry preparation system, complete with internal controls wired and
interlocked together and brought out to terminal blocks for remote field
connection by the Contractor.
2.2.5
Ductwork and Draft Equipment
Provide induced draft fans including inlet boxes, dampers, and drives.
Provide ductwork between [economizer][air heater] outlet interfaces and
stack inlet including spray dryer absorber bypass reheat ducts, as
necessary. Provide test ports. Provide expansion joints, turning vanes,
dampers, damper operators, and seal air systems including fabric filter
baghouse dampers. Provide gas distribution devices in ductwork ahead of
baghouse to assure even flow of gases into baghouse.
SECTION 23 51 43.00 20
Page 28
2.2.6
Instrumentation and Control Devices
Provide system controls and instrumentation including local control panels
and a remote control panel to be located in the main plant control room.
2.2.7
Structural and Miscellaneous Steel
Provide structural and miscellaneous steel including structural steel for
support of equipment, ductwork, platforms, walkways and stairs, and
miscellaneous framing. Provide stairs, walkways and access platforms, and
as required for normal operation and maintenance.
2.3
SITE FABRICATED AUXILIARY CONSTRUCTION
**************************************************************************
NOTE: Penthouse and hopper enclosures shall be
specified. Enclosed areas improve maintenance and
lower heating requirements.
**************************************************************************
Provide concrete foundations with anchor bolts conforming to ASTM A307for
structural steel columns and equipment. Also, provide metal siding and
roofing, insulation, doors, windows, and heating and ventilating equipment
for spray dryer sulfur dioxide absorber, for fabric filter baghouse
penthouse and hopper enclosures, and for the lime slurry preparation system
enclosure. Provide insulation and lagging including necessary subgirts for
spray dryer sulfur dioxide absorbers, baghouses, and ductwork. Also,
provide insulation and heat tracing for piping, as necessary, and in
accordance with the equipment specification requirements. Provide a remote
bulk lime storage silo, conveying system, and piping for connection to
Contractor's lime feed bin fill piping. Provide ash conveying equipment
from hopper flanges on the fabric filter baghouses and the absorber product
holding bins. Also, water storage tanks along with potable (non-process)
water piping, fire protection water piping, and field-installed instrument
air tubing. Provide electrical field wiring and conduit, lighting, and
motor control centers for 4,000-volt motors.
2.4
SITE CONDITIONS
**************************************************************************
NOTE: Dry and Wet Bulb Temperature and Duration:
Parameter
Season
Temperature (Degrees C)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Wet Bulb
Jun-Sep
[_____]
[_____]
SECTION 23 51 43.00 20
Page 29
Parameter
Season
Temperature (Degrees F)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Wet Bulb
Jun-Sep
[_____]
[_____]
**************************************************************************
Contractor shall use site conditions of elevation, design ambient
temperature, and design dry and wet bulb temperature, and duration
(differentiate for different seasons including frequency of occurrence of
higher temperatures) specified.
2.5
OPERATING INSTRUCTIONS
2.5.1
Steam Generators
**************************************************************************
NOTE: Insert appropriate Section number and title
in the blanks below using format per UFC 1-300-02.
**************************************************************************
The system shall be designed for operation with [the boiler(s) specified in
[_____]] [boiler(s) manufactured by [_____], Type [_____], Model No.
[_____]]. The steam generator is [a new] [an existing] [pulverized
coal-fired] [spreader stoker-fired] [underfeed stoker-fired] boiler.
Operating conditions for each steam generator at its maximum rating are:
a.
Type firing [_____]
b.
Steam flow, kg/s lb/hr [_____]
c.
Steam pressure, kPa (gage) psig [_____]
d.
Steam temperature, degrees C degrees F [_____]
e.
Gross heat input, kW 106 Btu/hr [_____]
f.
Excess air leaving boiler, percent [_____]
g.
Grade elevation, meters feet above mean sea level [_____]
For purposes of the proposal, the Contractor shall assume that the gross
heat input at any fractional load rating is that same fraction of the
maximum rated heat input given above.
2.5.2
Fuels
The steam generator shall utilize a fuel with following properties:
Coal:
SECTION 23 51 43.00 20
Page 30
Provide multiple-slurry atomizers for each spray dryer absorber, each with
its own flue gas plenum to ensure adequate contact of the flue gas with the
atomized slurry. Atomizers supplied under this paragraph shall be of the
two-fluid nozzle design using compressed air as the atomizing fluid and
shall have a proven record of efficient and reliable service in previous
lime slurry applications. Atomizers shall be provided with quick
disconnects on the compressed air and lime slurry feed lines to allow rapid
changeout of atomizers while the steam generators are on-line. Air
compressors shall be as specified in this paragraph. Nozzles shall be the
internal mixing type so that the compressed air and the lime slurry are
mixed internally to the nozzle orifice, resulting in the atomization of the
slurry. Internal surfaces of the nozzle which are subject to wear shall be
made of a suitable abrasion-resistant material and shall be easily
replaceable. Atomizer operation shall be monitored remotely in the steam
plant control room and locally in the absorber penthouse. Provide
instrumentation, controls, and alarms, as necessary, to ensure proper
operation of the atomizers. Slurry flow and pressure and air flow and
pressure in each atomizer feed line shall be monitored continuously.
Provide flow and pressure switches to indicate nozzle flow malfunction.
Control system shall automatically isolate any malfunctioning atomizer and
provide alarm annunciation in steam plant control room. Sufficient control
interlocks shall be furnished to assure that air flow to nozzle commences
first and terminates last relative to slurry flow during atomizer start-up
and shutdown. Atomizers shall be designed so that normal maintenance can
be performed by plant maintenance personnel who have been trained, as
specified in paragraph entitled "Operator Training Program." The dedicated
air compressor system provided with FGD systems utilizing two fluid-nozzle
atomization shall be complete with two air compressors, one operating and
one backup, and necessary controls and accessories required for automatic
operation. Each compressor shall be sized to provide at least 120 percent
of the maximum atomization air flow and pressure required. [As an
alternative to the preceding specified arrangement, individual air
compressors may be provided for each spray dryer absorber. Each unit shall
be sized to provide at least 120 percent of the maximum atomization air
flow and pressure required for operation of one spray dryer, and with all
[_____] units connected together, so that the unit normally dedicated to
the spray dryer for the idle boiler provides the required backup.] [For
either arrangement], [the] following features shall be provided: The air
compressors and all controls and accessories specified herein shall be
located inside an enclosure to provide an environment suitable for
compressor operation. Provide the structural and miscellaneous steel for
framing of the enclosure. Instrumentation and controls shall provide both,
local and remote monitoring, alarm annunciation, and automatic transfer to
backup unit in the event of failure of the operating unit.
2.7.2.3
Spare Equipment
One complete spare atomizer assembly shall be provided for every two
installed assemblies. Spare atomizer assemblies shall require only the
connection of lime slurry and air feed lines to allow insertion and
operation in place of a malfunctioning assembly. In addition, provide
spare nozzle wearing surface component parts, and other atomizer component
parts as required for one year's operation. Provide two complete sets of
tools required for disassembly and assembly of atomizer units.
2.7.3
Monorail and Hoist
Provide permanent hoist and monorail system for each spray dryer absorber,
as required, to install and remove atomizers. Monorail and hoist system
SECTION 23 51 43.00 20
Page 44
shall conform to NFPA 70. Monorail shall extend beyond edge of absorber
with sufficient clearance to allow lowering of atomizer assembly to ground
level and raising from ground level. Hoisting system shall be designed in
accordance with MHI MH27.1 and ASME HST-4. Provide wire rope electric
hoist with motor-operated trolley. Rope drum shall be sized for full lift
from ground level. Hoist capacity shall be 150 percent of heaviest piece
of equipment to be lifted during atomizer installation or removal or 908
kilograms 2,000 pounds, whichever is heavier. Capacity shall be clearly
indicated on hoisting equipment. Factor of safety for hoisting equipment
shall be not less than five on load-sustaining parts based on ultimate
strength. Hoist shall be provided with automatic mechanical load brake and
electric motor brake, either of which will sustain rated load in any
position. Monorail shall have minimum capacity of 150 percent of heaviest
piece of equipment to be lifted or 908 kg 2,000 pounds, whichever is
heavier. Provide angle stops on the monorail at each end to prevent trolley
over-travel. Provide 460 volt, 3-phase, 60-hertz, totally-enclosed, roller
ball-bearing type motor rated on 30-minute, 55-degree C rise-duty basis,
specifically designed for NEMA Class 2--Light Duty Industrial Service for
cranes. Monorail and hoist control shall be by push button station
suspended from hoist on pendant cord of sufficient length to allow
operation from penthouse floor or walkway level. Push buttons shall
control all hoist and trolley motions and shall provide "dead-man" control
action. Enclosed reversing-type magnetic starters shall be mounted on
hoist. Upper and lower limit switches shall be provided to prevent hood
over-travel. Provide double-acting limit switch to prevent trolley
over-travel in either direction. Conductor system shall be rigid enclosed
safety-type runway conductor, supported and insulated to conform to NFPA 70.
2.7.4
Absorber Product Removal System
Provide necessary equipment, structural support steel, instrumentation, and
controls required for continuous removal, transfer, and short-term storage
of absorber product material and fly ash from the bottom hopper section of
each spray dryer absorber vessel. The design capacity of the conveying
equipment provided shall be at least 120 percent of the maximum expected
rate of accumulation of fly ash and absorber product in the vessel based on
the specified maximum inlet loadings of sulfur dioxide and particulate. The
Contractor's conveying system shall continuously transfer the collected
material to a holding bin or bins from which the ash handling system will
intermittently convey it to an ash silo. The total capacity of the holding
bins provided shall be not less than that required to store the quantity of
fly ash and absorber product material representing ten hours of operation
of the conveying system at design capacity. The holding bin or bins shall
be provided with auxiliary equipment, controls and instrumentation required
to keep the control room operator informed as to the system status,
minimize fugitive dust emissions and maintain the flow of material to the
ash handling system when needed. Structural design requirements shall be
as specified. Structural design shall be based on a density of 47 kg per
cubic meter 100 pounds per cubic feet. Capacity shall be based on a
density of 16.5 kg per cubic meter 35 pounds per cubic feet. Provide a
flanged outlet connection for interface with the ash handling system to be
provided by the Contractor.
2.8
FABRIC FILTER BAGHOUSES
**************************************************************************
NOTE: The use of an electrostatic precipitator
(ESP) with the dry scrubber instead of a fabric
filter baghouse is not acceptable.
SECTION 23 51 43.00 20
Page 45
**************************************************************************
Provide [_____] fabric filter baghouses, complete with flue gas bypass,
inlet and outlet flue gas manifolds, dampers, bags and bag attachment with
support hardware, ash collection hoppers, pulse jet or reverse gas cleaning
systems, and accessories required for a complete and operable installation.
Each fabric filter baghouse shall meet the performance criteria specified
in paragraph entitled "Particulate Removal Performance Guarantees." The
fabric filter baghouses will be operated on the suction side of the induced
draft fans, as indicated. Each fabric filter baghouse shall have a minimum
of four lighted modules. The modules shall be arranged in two rows with
the inlet and outlet flue gas manifolds located between the rows of
modules. The design and arrangement of the fabric filter baghouses shall
complement the spray dryer absorbers, fans and ductwork such that the
complete Flue Gas Cleaning System installation meets the space requirements
indicated. Each fabric filter baghouse shall be provided with framing for
a penthouse area as required to allow bag replacement, [damper and damper
operator maintenance] [and] [pulse valve maintenance] in a protected
environment. Structural design requirements shall be as specified in the
paragraphs entitled "Fabric Filter Baghouses," "Structural and
Miscellaneous Steel," and in this paragraph. Submit information on the
categories general arrangement, foundation design, structural fabrication,
piping, erection, insulation, instrumentation, internal arrangement, and
valves. Exterior ferrous metal surfaces of the baghouse system including,
but not limited to, fabric filter baghouse modules, hoppers, support
structures, manifolds, handrails, and kickplate shall be properly cleaned
and shop primed, as specified. Surfaces that will be exposed to the flue
gas flow need not be painted, but shall be protected during shipment and
storage with a suitable rust-preventative coating, as recommended by
manufacturer. The fabric filter baghouses shall conform to ICAC F-2,
ICAC F-3, and ICAC F-5.
2.8.1
Pulse Jet Cleaning Systems
**************************************************************************
NOTE: Air compressor is specified in paragraph
entitled "Two-Fluid Nozzle Atomizers."
**************************************************************************
**************************************************************************
NOTE: Factors involved in selecting fabric filter
bag materials include:
1.
Duration of cleaning.
2.
Type of cleaning arrangements.
3.
System temperature level.
4.
Coal type.
5.
Sulfur dioxide removal efficiency.
NEEDLED felts are most commonly specified for
pulse-jet units. Precoat bags with fly ash prior to
operation. Fabric specifications are dependent upon
material.
**************************************************************************
SECTION 23 51 43.00 20
Page 46
a.
Gas flow, L/s
b.
Gas temperature, degrees C (before [economizer][air heater])
c.
Specific volume, L/kg
d.
Dust loading, gram/L
e.
Absolute humidity, kg H20/kg dry gas
Design
Range
Design
Range
Normal operation
During sootblowing
f.
S02, kg/s (full load)
a.
Gas flow, acfm
b.
Gas temperature, degrees F (before [economizer][air heater])
c.
Specific volume, acf/lb
d.
Dust loading, gr/acf
e.
Absolute humidity, lb H20/lb dry gas
Normal operation
During sootblowing
f.
S02, lb/hr (full load)
Conditions during sootblowing are based on the injection of steam [_____]
kPa (gage) psigat a rate of [_____] kg/s lbs/min during the sootblowing
cycle. The cycle is expected to last approximately [_____] minutes.
2.6.2
Spray Dryer Absorbers
**************************************************************************
NOTE: Specified percent sulfur dioxide removal must
be identical to paragraph entitled "QUALITY
ASSURANCE."
**************************************************************************
Each spray dryer absorber shall be designed in conjunction with its
associated fabric filter baghouse to remove a minimum of [_____] percent of
the sulfur dioxide present in the flue gas leaving the steam generator for
any flue gas condition specified and burning any coal within the range
specified.
SECTION 23 51 43.00 20
Page 34
2.6.3
Fabric Filter Baghouses
**************************************************************************
NOTE: Emission rates will depend upon local or
state air pollution regulations. Negotiations with
the agencies may be necessary.
**************************************************************************
**************************************************************************
NOTE: Typical fly ash densities are 560 kg/m 335
lbs/ft3 for hopper design capacity and 1440 kg/m3 90
lbs/ft3 for hopper design load.
**************************************************************************
**************************************************************************
NOTE: Dry and Wet Bulb Temperature and Duration:
Parameter
Season
Temperature (Degrees C)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Wet Bulb
Jun-Sep
[_____]
[_____]
Season
Temperature (Degrees F)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Wet Bulb
Jun-Sep
[_____]
[_____]
Parameter
**************************************************************************
Each fabric filter baghouse shall be designed to reduce maximum particulate
emissions leaving the baghouse to not more than [_____] kg/106 kJ lbs/106
Btu of heat input to the boiler for any gas flow conditions specified and
burning any coal within the specified range. Each fabric filter baghouse
shall be divided into a minimum of flue modules. The maximum air-to-cloth
ratio excluding one module for cleaning and one module for maintenance
shall be 4.0 for pulse-jet units or 2.25 including the reverse gas volume,
for reverse gas units with the spray dryer operating at the design gas flow
specified in paragraph entitled "Expected Flue Gas Conditions."
Calculation of air-to-cloth ratio for reverse gas fabric filter baghouses
shall exclude thimble, ring, and cuff area covered by bags. Pulse-jet
fabric filter baghouses, if provided, shall be designed for off-line
SECTION 23 51 43.00 20
Page 35
cleaning during normal operation with the capability for on-line cleaning
when required. Reverse gas fabric filter baghouses shall provide a maximum
of three-bag reach. Reverse gas bag cleaning systems shall provide a
minimum of 9 liter per second per square meter 1.75 cubic feet per minute
per square foot of fabric to be cleaned. Hopper capacity shall allow for a
minimum of ten hours storage at maximum fly ash and absorber product
material loading. Hopper design capacity shall be based on a fly ash
density of [_____] kilogram per cubic meter pounds per cubic feet. Hopper
design strength shall be based on fly ash density of [_____] kg per cubic
meter pound per cubic feet plus the support of 454 kg 1,000 pounds of ash
handling equipment per hopper. Structural design shall be based on the
assumption that the hopper is full of ash up to the bottom of the bags for
pulse-jet units or up to the tube sheet for reverse gas units. Fabric
filter baghouse structural design temperature range: [_____] to [_____]
degrees C degrees F.
2.6.4
Lime Slurry Preparation System
**************************************************************************
NOTE: Design slaker enclosure with adequate access
area around feeders, slakers, and grit removal
equipment to perform required maintenance.
**************************************************************************
A single lime slurry preparation system shall serve all spray dryer
absorbers. The lime feed bin shall be sized to store at least the quantity
of lime required for 72 hours operation of two steam generators at the
maximum sulfur dioxide rate specified and at the guaranteed stoichiometry.
The minimum storage volume shall be [_____] cubic meter feet. Provide the
bin with two conical hoppers. The lime feed bin shall be capable of
receiving lime either directly from self-unloading blower trucks or from a
remote silo and pneumatic conveying system to be provided by the
Contractor. Lime shall be slaked with detention or paste-type slakers.
Two full-capacity lime feeders and slakers shall be provided. Each lime
feeder and slaker shall be sized to provide 110 percent of the slurry
quantity required during operation of 2 steam generators at the maximum
sulfur dioxide rate specified. The turndown capability from this design
capacity shall be at least 10 to one. The lime slurry preparation system
shall provide 100 percent installed spare capacity feeders, slakers, and
grit removal equipment. The lime slurry system will operate with one
equipment train in operation and one as backup. The FGD system control
panel in the steam plant control room shall provide complete operational
monitoring of and alarm annunciation for each equipment train. Capability
for emergency shutdown of the lime slurry preparation system shall be
provided at the FGD system control panel. Failure of the operating
equipment train to respond to the automatic start signal from the low tank
level switch shall be alarmed in the control room. The slurry tank storage
capacity between the low and low-low levels shall be sufficient to allow
time for the control room operator to dispatch operations personnel to the
lime slurry preparation system to start-up the backup train and to provide
slurry to the tank before the low-low level is reached. Enclosed feeders
shall include equipment to protect the lime from moisture. Slakers shall
discharge slurry by gravity flow into product tank. Slurry preparation
system shall include positive means of removing sufficient grit from the
slurry to assure proper operation of the slurry feed system and the spray
atomizers. Grit shall be conveyed to a disposal bin provided by the
Government. Provide emergency eyewash stations at each level in the lime
slurry preparation system enclosure. Provide piping to exterior of
enclosure for connection to potable water piping system provided by the
SECTION 23 51 43.00 20
Page 36
Contractor.
2.6.5
Ductwork
**************************************************************************
NOTE: Ductwork velocities shall be such to maintain
self-cleaning conditions.
**************************************************************************
Ductwork upstream of the fabric filter baghouse outlets shall be designed
for a velocity of [_____] meter per second feet per minute at the design
flue gas flow, specified in paragraph entitled "Expected Flue Gas
Conditions." Ductwork downstream of the fabric filter baghouse outlets
shall be designed for a velocity of [_____] m/s fpm at the design flue gas
flow, specified in paragraph entitled "Expected Flue Gas Conditions."
Ductwork from the fabric filter baghouse outlet to the stack inlet shall be
designed to withstand a transient internal pressure (80 percent of yield
strength) range of minus 2490 Pa to plus 7470 Pa 10 inches Water Column
(WC) to plus 30 inches WC without permanent deformation of any structural
member at yield or in buckling.
2.6.6
Induced Draft Fans
**************************************************************************
NOTE: Pressures and air flows will be site specific
and will require system analysis.
**************************************************************************
**************************************************************************
NOTE: Dry and Wet Bulb Temperature and Duration:
Parameter
Season
Temperature (Degrees C)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Wet Bulb
Jun-Sep
[_____]
[_____]
Season
Temperature (Degrees F)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Parameter
SECTION 23 51 43.00 20
Page 37
Parameter
Wet Bulb
Season
Temperature (Degrees F)
Frequency of Occurrence of
Higher Temperatures
Jun-Sep
[_____]
[_____]
**************************************************************************
Test block flow capacity shall be [_____] actual liter per second cubic
feet per minute. Test block static pressure shall be 140 percent of the
static pressure required to withdraw [_____] L/s cfm from the
[economizer][air heater] outlet interface through the FGD system and to
provide [_____] Pa inches WC at the stack inlet plus [_____] Pa inches WC
which is equal to 140 percent of the static pressure required to withdraw
the design flow from the steam generator to the [economizer] [air heater]
outlet. The static pressure requirement shall be based upon normal
operation of the FGD system, except that the fan inlet temperature shall be
assumed to have the value specified in paragraph entitled "Sulfur Dioxide
Removal Performance Guarantees." The design and construction of the fan
shall be capable of withstanding operation at the maximum gas flow and
temperatures which would result, if the spray dryer was not in operation.
Test block capacity and static pressure shall be calculated assuming inlet
gas temperature to be 93 degrees C 200 degrees F.
Design ambient
temperature for lubrication system shall be [_____] degree C degree F to
[_____] degree C degree F. Induced draft fan speed shall not exceed
[_____] rpm.
2.6.7
Sulfur Dioxide Removal Performance Guarantees
**************************************************************************
NOTE: Stoichiometry for dry scrubbing is defined as
the moles of fresh slaked sorbent introduced to the
system divided by the moles theoretically required
for complete reaction with all of the sulfur dioxide
entering the system whether or not it is all
removed. This is opposed to wet scrubbing where
stoichiometry is generally based on moles of sulfur
dioxide removed by the system. Absorbent
stoichiometry directly affects sulfur dioxide
removal in the spray dryer. For example, a reported
stoichiometric ratio of 1.2 for a dry system
achieving 80 percent sulfur dioxide removal would be
equivalent to 1.5 for a wet scrubbing system. The
absorbent stoichiometry may be raised by an increase
in the amount of absorbent fed to the spray dryer. A
higher absorbent stoichiometry enhances removal of
sulfur dioxide.
**************************************************************************
**************************************************************************
NOTE: The compensatory damages for exceeding the
guaranteed stoichiometry will be determined on the
basis of $_____ for each 45 g mole CaO/g mole 0.10
lb mole CaO/lb mole sulfur dioxide increase above
the guaranteed stoichiometric ratio. Deduction of
compensatory damages, if any, shall be included in
the processing of the final payment. The
compensatory damages exceeding guarantees power
SECTION 23 51 43.00 20
Page 38
consumption will be determined on the basis of
$_____ /kW. Deduction of compensatory damages, if
any, shall be included in the processing of the
final payment. The total power consumption will be
measured at the Government's power input to the FGD
system during the final acceptance tests.
**************************************************************************
The guaranteed sulfur dioxide removal efficiency of the Flue Gas Cleaning
System shall not be less than [_____] percent and the outlet sulfur dioxide
emission shall not exceed [_____] kg/106 kJ lb/106 Btu for any load on the
steam generators down to 30 percent of maximum rating while in any normal
operating mode (excluding sootblowing) and burning any coal within the
range specified, when the Government provides lime, water, compressed air,
and other utilities to the interface points in accordance with the
Contractor's process flow diagrams, material balances, and these
specifications. Contractor shall guarantee the removal efficiency
specified with any two boilers and their associated flue gas cleaning
equipment in operation at full load. For [_____] percent sulfur dioxide
removal efficiency, the Contractor shall guarantee the maximum system
stoichiometry (lb-mole of Ca0 per lb-mole of S02 entering the system) at
both 100 percent and 50 percent of the maximum rating of the steam
generator and burning any coal within the range specified. The guarantee
at 50 percent rating shall be based on 50 percent of the design gas flow by
weight and an inlet gas temperature of 121 degrees C 250 degrees F.
Contractor shall specify minimum quality of lime on which stoichiometry
calculations are based as 90 percent available CaO by weight. Any increase
in the guaranteed stoichiometry at 50 percent rating and firing the average
coal will reduce the contract price. The operating stoichiometry will be
measured during the final acceptance tests. The measurements will be made
under normal operation and no special cleaning, adjustments or other
preparations will be allowed. Contractor shall include in the design of
the FGD system the necessary provisions for accurate determination of
operating stoichiometry. The proposal shall include a description of the
method by which stoichiometry may be determined. Contractor shall
guarantee that an atomizer can be changed out while the steam generator
which it serves is operating.
2.6.8
Particulate Removal Performance Guarantees
**************************************************************************
NOTE: Emission rates will depend upon local or
state air pollution regulations. Negotiations with
the agencies may be necessary.
**************************************************************************
The maximum particulate emission leaving the fabric filter baghouses shall
not exceed [_____] kg/106 kJ lb/106 Btu for any flue gas conditions as
specified while in any operating condition and burning any coal within the
ranges specified. The maximum particulate emission shall be defined as the
average of three complete test runs which shall include a proportional part
of the boiler sootblowing cycle. Bag life shall be guaranteed for a
minimum of two years after date of first flue gas passage through the bags.
Fabric filter baghouse will normally be bypassed during 100 percent oil
firing due to plugging of bags, bag guarantee shall be based upon coal/oil
and soot combination firing only. Soot blowing, with fabric filter
baghouse in operation, shall not void guarantee. If 10 percent or more of
the bags in any given compartment fail within the guarantee period, the
Contractor shall replace and install all bags in that compartment at his
SECTION 23 51 43.00 20
Page 39
own expense. Replacement of bags on a one-by-one as-fails basis will not
normally be allowed. However, the Contractor will be granted the
opportunity to locate and replace bags which fail within 30 days of initial
start-up of each baghouse due to deficiencies in manufacture or improper
installation.
2.6.9
Lime Slurry System Performance Guarantees
The Contractor guarantees that the Gas Cleaning System shall meet the above
specified performance, based on the process material balances submitted.
The guaranteed process material balances shall be based on the following:
(a) Lime analysis and coal analysis as specified, (b) slaking water
analysis and temperature as specified, and (c) specified gas flows and
operating conditions. The Contractor shall guarantee the capacity of each
lime slaker at 110 percent of lime quantity required at maximum sulfur
dioxide rate.
2.6.10
Draft Equipment Performance Guarantees
The Contractor shall guarantee that dampers have no leakage of flue gas to
the atmosphere. The Contractor shall guarantee the maximum leakage across
each damper when the dampers are in the closed position and are operating
at the design conditions.
2.6.11
FGD System Operational Performance Guarantees
**************************************************************************
NOTE: The compensatory damages for exceeding the
guaranteed stoichiometry will be determined on the
basis of $_____ for each 45 g mole CaO/g mole 0.10
lb mole CaO/lb mole sulfur dioxide increase above
the guaranteed stoichiometric ratio. Deduction of
compensatory damages, if any, shall be included in
the processing of the final payment. The
compensatory damages exceeding guarantees power
consumption will be determined on the basis of
$_____ /kW. Deduction of compensatory damages, if
any, shall be included in the processing of the
final payment. The total power consumption will be
measured at the Government's power input to the FGD
system during the final acceptance tests.
**************************************************************************
The Contractor shall guarantee the maximum FGD system power consumption
with one boiler unit in operation at the maximum rating and burning any
coal within the range specified. The guaranteed maximum power consumption
shall include the power consumption for equipment of the FGD system
provided under this contract which would be in use when one boiler is in
operation. Any increase in this total guaranteed power consumption will
reduce the contract price. The total power consumption will be measured at
the Government's power input to the FGD system during the final acceptance
tests. Specifically, watt-hour meters accurate to within one percent will
be used to measure average power consumption at the motor control centers,
the induced draft fan drive motor and the atomization air compressor drive
motor (if applicable) during the period of the performance tests. The
measurements will be made under normal operation and no special cleaning,
adjustments or other preparations will be allowed. Design and operation of
the FGD system shall be based upon the requirement that stack inlet
temperature differential above acid dew point shall not drop below minus 7
SECTION 23 51 43.00 20
Page 40
degrees C below 20 degrees F and that fabric filter baghouse inlet
temperature differential above acid dew point shall not drop below 17
degrees C 30 degrees F. Operating temperatures will be maintained at or
above these levels during performance testing. The Contractor shall
guarantee the maximum pressure drop across the entire system at design flue
gas flow rate. The Contractor shall guarantee that the sound levels
specified for the baghouses, pumps, motors, and valves will not be exceeded.
2.7
SPRAY DRYER ABSORBERS
**************************************************************************
NOTE: Dry and Wet Bulb Temperature and Duration:
Parameter
Season
Temperature (Degrees C)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Wet Bulb
Jun-Sep
[_____]
[_____]
Season
Temperature (Degrees F)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Wet Bulb
Jun-Sep
[_____]
[_____]
Parameter
**************************************************************************
Furnish and deliver [_____] spray dryer absorbers, complete with slurry
atomizer units and accessories for a complete and operable installation.
Each spray dryer absorber shall meet the performance criteria specified in
paragraph entitled "Sulfur Dioxide Removal Performance Guarantees." The
absorbers shall be constructed of steel plate of 6 mm 1/4 inchminimum
thickness, conforming to ASTM A36/A36M. Structural steel design shall be
as specified in paragraph entitled "Structural and Miscellaneous Steel."
Structural design temperature range shall be [_____] to 204 degrees C 400
degrees F. External stiffening ribs shall be spaced as required to provide
support for the vessel shell, equipment, walkways, penthouse, monorail, and
hoist. Stiffeners shall be sized and positioned to provide a uniformly
curved surface for the installation of insulation and lagging. Structural
welded seams shall be seal welded. Joints shall be provided so that they
can be assembled airtight. Each spray dryer absorber shall be provided
with the necessary framing for a penthouse to provide shelter of atomizers,
motors, lubrication systems, control devices and other equipment located
above the spray chamber. Emergency eyewash stations shall be provided in
SECTION 23 51 43.00 20
Page 41
each penthouse. Potable water piping to eyewash stations will be provided
by the Contractor. The penthouse design shall be such that the overall
cylindrical appearance of the absorber shall be maintained. The rotating
assembly of each atomizer unit shall be tested for dynamic and static
balance using the actual driver. Complete test reports shall be submitted
to the Contracting Officer. Notify the Contracting Officer, in writing, at
least 20 days in advance of the tests so that he or his representative can
be present. The motor drivers shall be tested as specified in paragraph
entitled "Pumps, Valves, Motors." Two-fluid nozzle atomizer assemblies
shall be tested for proper atomization performance, plugging resistance and
wear resistance during actual flow of lime slurry and compressed air
through the nozzle, as required during operation. Submit information on the
categories general arrangement, foundation design, structural fabrication,
piping, erection, insulation, instrumentation, wiring, and electric
motors. Exterior ferrous metal surfaces of the spray dryer absorber
systems including, but not limited to, absorber vessels, holding bins,
support steel, manifolds, handrails and kickplate shall be properly cleaned
and shop primed, as specified. Mechanical and electrical component
equipment, such as atomizer machinery and control panels shall be provided
with the manufacturer's standard finishes. Ferrous surfaces which should
not be painted and are subject to corrosion shall be protected for the
period during shipment and storage with a suitable rust-preventative
compound as recommended by manufacturer.
2.7.1
Spray Dryer Absorber Vessel
The spray dryer vessel shall be cylindrical with a 60-degree conical bottom
section or with a trough-shaped bottom section with a minimum sideslope of
60 degrees above the horizontal. Provide replaceable wear plates, where
necessary. The absorber vessel shall be gas-tight and designed for a
transient condition (80 percent of yield strength) at internal pressures of
at least plus 4980 and minus 7470 Pa 20 and minus 30 inches water gage.
Stiffeners shall be of equal depth to provide a uniform surface to receive
insulation. The bottom section of the vessel shall be provided with hopper
heaters as specified in paragraph entitled "Fabric Filter Baghouse."
Heaters shall cover the bottom one-third of the hopper surface area.
Provide the hopper with poke holes, flanged discharge opening, mechanical
vibrators, strike plate and nuclear level switches, as specified in
paragraph entitled "Hoppers." A minimum of one access door on side of
vessel, as specified in paragraph entitled "Access," shall be provided for
access to the vessel interior for maintenance. Provide access doors with
external latches and tightening devices which will allow for gasket
shrinkage and yet produce a gas-tight seal. Doors shall be provided with
means for padlocking in the open position. Access shall be sufficient to
allow inspection of the vessel interior and removal and replacement of any
internal parts subject to erosion or corrosion.
2.7.2
Spray Dryer Atomizers
Each spray dryer sulfur dioxide absorber shall be provided with slurry
atomizers of the rotary or two-fluid nozzle type, as specified in the
following sections. Equip the spray dryer sulfur dioxide absorbers with
vanes, dampers, dispersers, and distributors required to ensure proper
contact of the flue gas with the atomized lime slurry. These devices shall
be designed to prevent maldistribution and short circuiting of flue gas and
localized abrasive impingement of fly ash on absorber internals. The gas
dispersers shall be designed to prevent the atomizer spray from impinging
on or wetting the vessel wall. Design the gas distribution devices to
provide contact between the gas and the atomized slurry as necessary to
SECTION 23 51 43.00 20
Page 42
driving motor, baseplate, drive coupling or multiple V-belt drive, and
coupling guard, as applicable. Include dowelling of pumps to baseplate.
Each pump shall be of a design and construction for service intended.
Overhead motor mounting structure shall have provision for drive belt
tension adjustment. Structure shall be such that motor and mounting are
supported independently of the pump bearing assembly. Provide structure to
allow for removal of pump bearing assembly without disturbing the motor.
Structure shall be of fabricated steel, and shall provide support for
V-belt drive guard. Drive couplings and matched multiple V-belt drive
(MVD) sets shall be rated at not less than 140 percent of the motor power.
Guard for matched MVD sets shall have solid metal cover on pump side and
expanded metal mesh on outboard end. Flexible drive coupling guards shall
comply with applicable safety requirements. Flexible coupling guards shall
be arranged for ease in disassembly or removal for access to couplings.
Coupling guards shall be rigidly fastened to baseplate. Prevent any
external thrust from being transmitted to the motor shaft under any
operating conditions. Provide double-screw adjustment bases on
nonadjustable horizontal arrangements. Suction and discharge connections
shall be standard Class 150 ANSI flat-faced flanges, rubber lined, if pump
is rubber lined. Furnish drawings and data as specified in paragraph
entitled "Submittals." Include in submittals information for the general
arrangement and outline, instrumentation, piping connection, electric
motors sound pressure ratings, description of flushing system for slurry
pumps, and performance curves.
2.10.1.1
Centrifugal Pumps
Pump speed shall be such that the upper limits of specific speed, as
defined by the applicable figure of the HI M100 are not exceeded at any
pump operating condition. Total dynamic head of pumps shall be maximum at
zero flow and continuously decreasing from zero flow to design flow. Head
capacity characteristics shall permit stable operation when pump is
operating alone or in parallel with other pumps of the same designation.
Pump shut-off head shall be more than 110 percent of design point head and
less than 150 percent of design point head. Pump shaft critical speeds
shall not occur from 10 percent of design point head. Pump shaft critical
speeds shall not occur from 10 percent to 120 percent of design rpm. Pump
shaft shall be free from excessive vibration at discharge rates from 10
percent to 120 percent of design delivery. Impeller shall not be maximum
or minimum size for pump casing furnished to allow for possible future
modification of head capacity furnished to allow for possible future
modification of head capacity characteristic by changing impeller size. The
maximum allowable sound pressure level shall be 84 dB for each pump-motor
unit. Slurry pumps shall be vertically split-case, rubber-lined
single-stage pumps designed for indoor service. Water pumps shall be
vertically split-case single-stage pumps designed for outdoor service.
Slurry pumps shall be provided with shaft seals which do not require water
flushing. Provide water pumps with mechanical shaft seals which do not
require an external source of seal water. Pumps shall be provided with
flexible inlet and outlet connections.
2.10.1.2
Vertically Split-Case Rubber-Lined Pumps
Vertically split-case rubber-lined pumps shall be end suction,
single-stage, single-suction centrifugal, of the volute type. Pump trim
shall be stainless steel suitable for the service and designed for
continuous operation at specified operating conditions. Pumps shall be
frame mounted with pump shaft carried on its own bearings with multiple
V-belt drive between pump and motor. Pumps shall have bottom horizontal
SECTION 23 51 43.00 20
Page 59
discharge. Pump casing shall be split vertically into suction inlet
assembly and pump assembly designed for ease of disassembly. Casing shall
have replaceable secured rubber liner, minimum 10 mm 3/8 inchthick designed
for long life under operating conditions specified. Pump impeller shall be
enclosed type, of soft natural rubber on steel skeleton. Pump shaft shall
be provided with ceramic faced shaft sleeves designed to prevent water
leakage between shaft and sleeve. Sleeve shall be adequately anchored to
the shaft to prevent any rotation of the sleeve relative to the shaft.
Shaft shall be keyed on the driven end for easy removal of the coupling
half. Shaft shall be completely encased along its entire length within the
wetted area by the impeller and shaft sleeves. Provide adequate fillets
for changes in diameter. Pump bearings shall consist of two bearing
assemblies, ball or tapered type roller type, mounted in an oil-filled or
grease-lubricated housing. Provide adequate seals to prevent leakage of
lubricant to outside and dust entry to inside of housing. Bearings shall
have 60,000-hour minimum B-10 life under design conditions in accordance
with ABMA 9 and ABMA 11. Design to limit maximum shaft deflection to 0.05
mm 0.002 inch. Provide with lubrication system consisting of a
constant-level oiler with level indicator or easily accessible grease
nipples as appropriate to the bearing design. Provide mechanical or
centrifugal shaft seals conforming to paragraph entitled "Centrifugal
Pumps." Furnish one spare set of shaft seals for each pump. Support
frames for all vertically split pumps shall be fabricated of structural
steel and heavy plate extending the full length of pump and driver. Design
to adequately support equipment under operating conditions without grout
fill inside the frame. Frame shall not be covered with a thin steel plate
which requires grouting under the plate, but the frame may be filled with
concrete as required for drainage. Grout shall be required under the basic
frame only. Contractor to provide minimum 25 mm one inch pipe drain in the
perimeter of the frame. Drawings shall indicate the required concrete fill
lines for proper drainage. The pump shall be dowelled shall be dowelled to
the frame in the shop; the driver shall be dowelled in the field. Furnish
bolts or screws for attaching pumps and motor drives to the support frame.
Frames shall have grouting holes, 100 mm 4 inch minimum size, to facilitate
proper grouting, if area is covered. Materials of construction shall be as
specified below.
Part Name
Material
Casing
Cast iron or steel, ASTM A48/A48M with replaceable
rubber liners
Impeller
Soft rubber on steel skeleton
Shaft
Heat-treated carbon, or stainless steel,
ASTM A276/A276M, Type 410
Shaft Sleeve
Ceramic faced
Baseplate Steel
ASTM A36/A36M
2.10.1.3
Vertically Split-Case Pumps
Vertically split case pumps shall be end suction, single-stage,
single-suction centrifugal, of the volute type. Pumps shall be bronze
trimmed, and designed for continuous operation at specified operating
conditions. Pumps shall be frame-mounted with pump shaft carried on its
own bearings with flexible coupling between pump and motor. Pump
orientation to fit piping arrangement. Pump casing shall be split into
suction inlet assembly and pump assembly. Design for ease of disassembly,
SECTION 23 51 43.00 20
Page 60
allowing the rotating assembly and bearing housing to be removed without
disconnecting pipe or moving the motor. Provide renewable casing rings
locked against rotation, with one ring mounted in suction inlet assembly
and the other ring mounted in pump assembly. Provide with casing vent and
drain connections. Pump casing shall be back pull out design. Pump
impeller shall be enclosed type, fully machines throughout. Axial balance
shall be obtained by balancing ports and rear sealing rings. Casing and
impeller wear rings shall be of different hardness designed for long
wearing qualities. Pump shaft shall be provided with shaft sleeve designed
to prevent water leakage between shaft and sleeve. Sleeve shall be
anchored to the shaft to prevent any rotation of the sleeve relative to the
shaft. Shaft shall be keyed on the driven end for easy removal of the
coupling half. Shaft shall be completely encased along its entire length
within the wetted area by the impeller and shaft sleeves. Provide adequate
fillets for changes in diameter. Design to limit the maximum shaft
deflection at the stuffing box to 0.05 mm 0.002 inch. Pump bearings shall
consist of two bearing assemblies, tapered-roller type, mounted in an
oil-filled housing. Provide adequate seals to prevent leakage of oil to
outside and dust entry to the inside. Bearings shall have 60,000 hour
minimum B10 life under design head conditions. Bearing loading for thrust
determination shall be at the most adverse operating condition of the
pump. Provide with oil lubrication system including oil level indicator.
Seals shall be single, mechanical type of the inside, balanced design.
Seal face materials shall be selected to provide long life in the service
intended. Factory-installed seal water piping shall be provided from pump
discharge to inlet connection on seal housing as required to cool and
lubricate the seal faces. Seal water loop shall include a valve or orifice
to control flow. Provide a spare seal for each pump. Support frames for
vertically split pumps shall be fabricated of structural steel and heavy
plate extending the length of pump and driver, rigid enough to maintain
alignment of machinery, and designed to adequately support equipment under
all operating conditions without grout fill inside of the frame. Frame
shall not be covered with a thin steel plate which requires grouting under
the plate, but the frame may be filled with concrete as required for
drainage. Grout shall be required under the basic frame only. Contractor
to provide one inch minimum drain in the perimeter of the frame.
Drawings
shall indicate the required concrete fill lines for drainage. The pump
shall be dowelled to the frame in the shop, the driver will be dowelled in
the field by others. Furnish bolts or screws for attaching pumps and motor
drives to the support frame. Frames shall have grouting holes, 100 mm 4
inch minimum size, to facilitate proper grouting. Materials of
construction shall be as specified.
Part Name
Material
Casing
Cast iron or steel, ASTM A48/A48M with replaceable
rubber liners
Impeller
Bronze, ASTM B584
Shaft
Heat-treated carbon, or stainless steel,
ASTM A276/A276M, Type 410
Shaft Sleeve
11-13 percent chrome steel, 450 minimum Brinell
hardness, ASTM A743/A743M
Casing rings
Bronze, ASTM B103/B103M
SECTION 23 51 43.00 20
Page 61
Part Name
Material
Impeller rings
Bronze, ASTM B103/B103M
Baseplate Steel
ASTM A36/A36M
2.10.1.4
Vertical Wet Pit Pumps
Vertical wet pit pumps shall be end suction, single-stage, single-suction
centrifugal of the volute type. Pump trim shall be 316L stainless steel
designed for continuous operation at specified operating conditions. Pumps
shall be frame mounted with pump shaft carried on its own bearings with
multiple V-belt drive between pump and motor. Provide suitable connections
on the frame for lifting and lowering of the pump. Pump casing, pipe shaft
column, discharge piping, and submerged materials, shall be rubber-coated a
minimum of 6 mm 1/4 inch thick. Pump casing shall be split perpendicular
to shaft. Provide renewable impeller wear rings locked against rotation.
Casing shall have replaceable rubber liner, minimum 10 mm 3/8 inch thick
designed for long life under operating conditions specified. Casing shall
be rubber covered. Pump impeller shall be enclosed type of soft natural
rubber on steel skeleton. Pump shaft shall be provided with hardened
(minimum 450 BHN) stainless-steel shaft sleeves designed to prevent water
leakage between shaft and sleeve. Sleeve shall be adequately anchored to
the shaft to prevent any rotation of the sleeve relative to the shaft.
Shaft shall be keyed on the driven end for easy removal of the coupling
half. Shaft shall be completely encased along its entire length by the
impeller and shaft sleeves. Shaft shall have fillets for changes in
diameter. Shaft shall be designed to carry torsional and axial thrust
loads. Shaft shall be one-piece construction. Shaft support column shall
be rubber covered. Upper bearing assembly shall be ball or tapered-roller
type, mounted in an oil-filled or grease-filled housing. Include adequate
seals to prevent leakage of lubricant to outside and dust entry to the
inside. Bearings shall have 60,000-hour minimum B10 life under design head
conditions. Provide with adequate lubrication system. Provide with dust
and oiltight seals. Pump shall have no submerged bearings. Provide shaft
seals as specified in paragraph entitled "Vertically Split-Case
Rubber-Lined Pumps." Pump baseplate shall be of fabricated steel, of
adequate size and thickness to prevent excessive vibration and deflection.
Provide holes for mounting of the pump and necessary piping as required.
Baseplate shall be rubber-coated on the bottom side. Provide with shims,
bolts, and other devices required for proper alignment and anchorage.
Anchor bolts required in foundation will be furnished by the Contractor.
Materials of construction shall be as specified below.
Part Name
Material
Casing
Cast iron or steel, ASTM A48/A48M rubber covered with
replaceable rubber liner
Impeller
Soft rubber on steel skeleton
Shaft
Heat-treated carbon, or stainless steel,
ASTM A276/A276M, Type 410
SECTION 23 51 43.00 20
Page 62
**************************************************************************
NOTE: Insert appropriate Section number in the
blanks below.
**************************************************************************
The fabric filter baghouse assembly shall be of modular construction. The
inner housing casing and tube sheet of each module shall be fabricated from
carbon steel plate of 5 mm 3/16 inch minimum thickness, conforming to
ASTM A36/A36M. The inner casing shall be of welded construction, gastight
and watertight, designed for a transient condition (80 percent of yield
strength) at internal pressures of at least plus 4980 and minus 7470 Pa
plus 20 and minus 30 inches water gage. Joints shall be sealed by
continuous fillet or continuous complete penetration groove welds, as
applicable. The tube sheet opening arrangement and bag clearance shall
limit gas velocity between the bags at any point within the module to not
more than 1.27 m/s 250 ft/min at design conditions. Bag to wall clearance
used in calculating gas velocity shall not exceed bag to bag clearance.
Minimum bag clearance shall be 50 mm 2 inches. Additional space shall be
provided between rows of bags, as necessary, to clear access door supports
crossing the tube sheet. Tube sheet shall be continuous fillet or
continuous complete penetration groove welded gastight so that all flue gas
must pass through the bags. No caulking or sealing materials shall be
used. Tube sheet shall be arranged for individual top bag and cage removal
and reinforced, as required for pedestrian traffic (minimum support shall be
488 kg per square meter 100 pounds per square foot). Modules shall have
shop insulated, double-cased lift-off doors with quick-opening handles for
access to the tube sheet. Doors shall have high-temperature gaskets to
prevent air infiltration. Multiple tube sheet access doors shall be
provided such that each door shall be easily removable by two men. The
doors shall be provided with lifting handles. Top surface of access doors
shall be 6 mm 1/4 inch thick ASTM A36/A36M four-way raised pattern floor
plate. The manufacturer's standard tube sheet access door arrangement and
design will be considered provided the design provides adequate insulation
and protection against infiltration. The bag cleaning system shall be
designed to ensure efficient cleaning operation with a minimum pressure
drop across the system and with the gentlest possible cleaning mechanism to
ensure long bag life. Source of compressed air is specified under Section
[_____] COMPRESSED AIR SYSTEMS. Compressed air used in the cleaning system
shall pass through a dryer/filter system. The dryer shall be provided to
remove moisture from compressed air used in system. Dryer shall remove
sufficient moisture to provide a maximum dewpoint of [_____] degree C at
690 kpa (gage) degree F at 100 psig. A filter system shall be provided to
clean compressed air used in system. Filter system shall remove a minimum
of 90 percent to 95 percent of particles greater than 0.6 microns in
diameter. Filters shall be sized to operate for 90 days without service
under normal operating conditions and shall be easily accessible for
inspection and service. Dryer/filter system shall be sized service.
Dryer/filter system shall be sized for 120 percent of design air flow.
Dewpoint should be 6 degrees C 10 degree F lower than design minimum
temperature. In no case should a dewpoint be greater than 2 degrees C 35
degrees F. Each module shall have a factory-installed compressed air
header, pulse valves, and distribution piping. Valves and wiring shall be
located in a weather protected enclosure with forced air ventilation to
prevent freezing or overheating. The enclosure shall be readily accessible
through hinged doors. Diaphragm valves shall be factory prewired to a
junction box. Entire pulsing system shall be removed with top door or
other provisions shall be made such that piping does not interfere with bag
replacement. Connections to compressed air headers and distribution pipes
shall be made with flexible hose with automatic shutoff quick connect
SECTION 23 51 43.00 20
Page 47
fittings for ease of removal during maintenance. Each row of bags shall be
serviced by its own pulse valve and distribution pipe so that only one row
of bags shall be cleaned per each compressed air pulse. The pulse valves
shall be heavy-duty diaphragm type with solenoid actuators and
stainless-steel internals. Pulse valves shall be designed to limit noise
from pulse valve operation to not more than 84 dBA measured 1 1/2 meters
five feet from the valves. Compressed air and instrument air piping for
each fabric filter baghouse shall be piped back to a single point within
the battery limits of the collector(s) as indicated for connection with the
steam plant piping system to be provided by the Contractor. Contractor's
piping shall include shut off valves, pressure gages, pressure regulating
stations, filters, surge tanks, and other equipment required for complete
operation of the cleaning system. For off-line cleaning modules shall be
sequentially isolated by closing the outlet valve. Manufacturer to
recommend off-line times. When the module is off-line, each row of bags
shall be individually pulsed with 483 to 690 kPa (gage) 70 to 100 psig
compressed air through a solenoid-piloted, heavy duty diaphragm valve.
Each bag support cage shall be fitted with a diffuser element. After bags
are cleaned, the module shall be held off-line for a period of time
sufficient to allow the dust to settle into the hopper. The bags to be
furnished shall be of a fabric type, weight, finish, and construction
suitable for the intended service. Bags shall be suitable for continuous
exposure to the flue gas temperature conditions at the economizer outlet.
Bags and cages shall be provided with coatings as necessary to minimize
abrasion and to resist acid or alkali attack. Bags shall not be more than
150 mm 6 inches in diameter and not more than 4 1/2 meters 15 feet in
length. Bag cage design and construction shall be suitable for the
intended service. Bags shall be clamped at top between cage and tube sheet
in such a manner that bags will not sway, but can be readily removed
without special tools. The manufacturer's standard cage design will be
considered, provided that it has a proven record of reliable services with
the bag material proposed. The method of attachment of bags and cages to
the tube sheet shall provide proper air seal, bag tension, and cage
alignment. If venturis are provided, they shall be the manufacturer's
standard type for this application. Special care shall be taken to assure
there are no rough spots on cages to cause bag abrasion. Provide equipment
and materials necessary for bag leak detection. Leak detection system
provided shall utilize a fluorescent powder for detection with ultraviolet
light. Furnish portable light and sufficient powder for one year of normal
inspections. Furnish sufficient bag capping devices for 5 percent of the
total installed number of bags. The Contractor shall precoat the bags for
initial start-up on oil.
2.8.1.1
Spare Equipment
Ten percent extra bags and two percent extra cages shall be furnished.
2.8.2
Reverse Gas Cleaning System
**************************************************************************
NOTE: Factors involved in selecting fabric filter
bag materials include:
1.
Duration of cleaning.
2.
Type of cleaning arrangements.
3.
System temperature level.
SECTION 23 51 43.00 20
Page 48
2.10.3.1
Motors Rated 3/8 kW 1/2 Horsepower and Smaller
Motors shall be rated at 115 volts, single-phase, 60 hertz, and have a
service factor of 1.0. The torque characteristics of each motor at
voltages from 90 to 110 percent rated voltage shall be as required to
accelerate the motor and driven equipment to full speed without damage to
the motor or the driven equipment. Insulation shall be Class B or Class F,
with Class B temperature rise in accordance with NEMA MG 1. Enclosures
shall be fabricated of steel. Horizontal motors shall be mounted on a
common baseplate with the driven equipment. Manual reset thermal overload
protection shall be furnished integral to each motor. Enclosures shall be
totally enclosed nonventilated.
2.10.3.2
Motors Rated 1/2 Through 149 kW 3/4 Through 199 H.P.
**************************************************************************
NOTE: The efficiency of each motor shall not be
less than that indicated in the following table:
Efficiency
Nameplate
3600 rpm
1800 rpm
1200 rpm
Kilowatt
Nominal
Minimum
Nominal
Minimum
Nominal
Minimum
0.746
81.5
78.5
84.0
81.5
78.5
75.5
1.21
81.5
78.5
84.0
81.5
84.0
81.5
1.49
84.0
81.5
84.0
81.5
86.5
84.0
2.24
86.5
84.0
88.5
86.5
88.5
86.5
3.73
88.5
86.5
90.2
88.5
88.5
86.5
5.60
88.5
86.5
90.2
88.5
88.5
86.5
7.46
88.5
86.5
90.2
88.5
90.2
88.5
11.19
90.2
88.5
91.7
90.2
90.2
88.5
14.92
91.7
90.2
91.7
90.2
91.7
90.2
18.65
91.7
90.2
93.0
91.7
91.7
90.2
22.38
91.7
90.2
93.0
91.7
91.7
90.2
29.84
91.7
90.2
93.0
91.7
93.0
91.7
37.30
91.7
90.2
94.1
93.0
93.0
91.7
44.76
93.0
91.7
94.1
93.0
93.0
91.7
SECTION 23 51 43.00 20
Page 68
Efficiency
Nameplate
3600 rpm
1800 rpm
1200 rpm
55.95
94.1
93.0
94.1
93.0
94.1
93.0
74.60
94.1
93.0
95.0
94.1
94.1
93.0
93.25
94.1
93.0
95.0
94.1
94.1
93.0
111.90
94.1
93.0
95.0
94.1
95.0
94.1
Efficiency
Nameplate
3600 rpm
1800 rpm
1200 rpm
Horsepower
Nominal
Minimum
Nominal
Minimum
Nominal
Minimum
1
81.5
78.5
84.0
81.5
78.5
75.5
1.5
81.5
78.5
84.0
81.5
84.0
81.5
2
84.0
81.5
84.0
81.5
86.5
84.0
3
86.5
84.0
88.5
86.5
88.5
86.5
5
88.5
86.5
90.2
88.5
88.5
86.5
7.5
88.5
86.5
90.2
88.5
88.5
86.5
10
88.5
86.5
90.2
88.5
90.2
88.5
15
90.2
88.5
91.7
90.2
90.2
88.5
20
91.7
90.2
91.7
90.2
91.7
90.2
25
91.7
90.2
93.0
91.7
91.7
90.2
30
91.7
90.2
93.0
91.7
91.7
90.2
40
91.7
90.2
93.0
91.7
93.0
91.7
50
91.7
90.2
94.1
93.0
93.0
91.7
60
93.0
91.7
94.1
93.0
93.0
91.7
75
94.1
93.0
94.1
93.0
94.1
93.0
100
94.1
93.0
95.0
94.1
94.1
93.0
125
94.1
93.0
95.0
94.1
94.1
93.0
SECTION 23 51 43.00 20
Page 69
5.
Sulfur dioxide removal efficiency.
NEEDLED felts are most commonly specified for
pulse-jet units. Precoat bags with fly ash prior to
operation. Fabric specifications are dependent upon
material.
**************************************************************************
Bag manufacturer shall furnish following actual test data for each bag
material lot used:
Permeability (ASTM D737)
MIT Flex (ASTM D2176)
Tensile Strength (ASTM D1682--Method IR-T)
Mullen Burst (ASTM D3887)
Weight (ASTM D3776/D3776M)
Thickness (ASTM D1777)
Count (ASTM D3775)
Yarn Weight (ASTM D578/D578M)
Fabric Treatment Content
The fabric shall meet the following specifications.
Permeability
[_____]
MIT Flex
[_____]
Tensile Strength
[_____]
Mullen Burst
[_____]
Weight
[_____]
Thickness
[_____]
Weave Thread Count (warp x fill)
[_____]
Yarn Weight
[_____]
Type of Finish
[_____]
Weight of Finish
[_____]
(Percent of fabric weight)
[_____]
Provide material lot analyses prior to manufacture of bags. Prior to
processing, the yarn shall be inspected for cleanliness, binder content,
broken filaments, denier and tensile strength. Substandard yarns shall be
rejected. Sizing applied to yarns shall be removed from the fabric prior
to applying the finish. Stitching used in filter bag fabrication shall be
made using [_____] thread. Filter bags shall be packaged and protected as
necessary to prevent damage during shipping and outdoor storage at the job
site. Material not meeting the requirements of this specification shall be
rejected and replaced with materials of the specified type and quality at
no additional expense to the Government. The Contracting Officer or his
SECTION 23 51 43.00 20
Page 51
representative shall have uninhibited access to areas in which the
fabrication of materials governed by the specifications takes place.
2.8.5
Hoppers
Hoppers shall be pyramidal-type fabricated from ASTM A240/A240M, type 317L
cold-rolled steel plate having a minimum thickness of 6 mm 1/4 inch.
Hoppers shall be properly stiffened, from the outside only, and shall be
constructed with a minimum valley angle of 60 degrees from the horizontal.
Hoppers shall be of welded construction and shall be welded to the modules
to form a gas-tight unit. Welded joints shall be sealed by continuous
fillet or continuous complete penetration groove welds as applicable.
Hoppers shall span no more than one module. Steel reinforcements not in
contact with the gas or ash may be either type 317L stainless steel or
ASTM A242/A242M structural steel. If the latter is used, welding rods
shall be specifically selected for the service. Provide protection of rods
against moisture whether for factory or field assembly. Provide key
interlocked access doors on each hopper on both sides of any hopper
baffle. Hopper access doors shall be interlocked to fly ash level
detectors to prevent access when the nuclear level detectors are
operational. Doors shall be in accordance with the requirements specified
in paragraph entitled "Structural and Miscellaneous Steel." Each hopper
shall be furnished with provisions for attachment of vibrators. Hoppers
shall have adequate flexibility for vibrating. Each hopper shall be
provided with two 100 mm 4 inch poke holes with a tee wash connection and
screw caps. Poke holes shall be positioned to permit downward thrusts into
the hopper. A special plate reinforced "pounding area" shall be furnished
on each hopper face for external manual vibrating. Each pounding plate
shall be 300 by 300 by 25 mm 12 by 12 inches by 1 inch thick plate steel
ASTM A36/A36M. A work platform with stairs shall be provided to each
pounding area for units with pounding areas more than 1 1/2 meters five feet
above ground. Approve location and arrangement of poke holes and pounding
areas by the Contracting Officer. Pounding plate shall not be insulated.
Insulation shall be neatly finished at this discontinuity. Each hopper
shall include a 300 mm 12 inch diameter 57 kg 125 pound flat face flanged
outlet connection to match ash conveying system to be provided by the
Contractor. Provide access hatch not less than 200 by 200 mm 8 by 8 inch
for cleanout within 200 mm 8 inches above the flange. Ash valve shall be a
minimum of 150 mm 6 inch diameter. Bolt-down type hatch is acceptable for
clean-out hatch. Provide each hopper with two mechanical vibrators, to be
located at mid-height on opposite sides. Vibrator controls shall be
interfaced with ash collection system to provide vibrator operation only at
the inception and during an evacuation cycle. Operation shall be
automatic. Manual override control for hopper vibrators and evacuation
system shall be provided in hopper area and shall be enclosed in cases to
prevent accidental energization of systems. A warning shall be placed over
the vibrator manual control with the following inscription: "Warning:
Vibrator Control. Do not activate unless hopper evacuation system is
operating." Provide nuclear hopper level switches as specified in
paragraph entitled "Instrumentation and Controls." Provide a hopper heater
system for each fabric filter baghouse. Each system shall be as specified
herein. Hopper heaters for each hopper shall be furnished by the collector
manufacturer and shall include material required for mounting. The system
shall be designed to provide a 93 degrees C 200 degrees F rise in
temperature in the hopper, in the vicinity of the heaters, during offline
and startup conditions. The system shall be designed to provide maximum
heater coverage between hopper stiffeners. The system shall be designed
with a minimum heating safety factor of 1.1 and a minimum wind heat loss
factor of 1.12. The system shall include a flexible throat heater for each
SECTION 23 51 43.00 20
Page 52
hopper. Heaters shall be of modular design except for throat heaters.
Flexible electric heating blankets or tapes, capable of withstanding 454
degrees C 850 degrees F, shall be used for areas where modular equipment
will not fit. Heater modules shall be designed for easy installation.
Heater modules shall cover at least 20 percent of the hopper area (covered
hopper area not to include exposed areas of poke holes, level detectors,
strike plates, stiffeners, access doors, etc.), shall cover the bottom
portion of the hopper to the maximum extent possible, and shall extend at
least 50 percent up the hopper height. Hopper throats shall be heated with
blanket or tape heaters. Equipment furnished shall be designed and tested
to withstand natural and induced vibrations including manual rapping of the
strike plates. The hopper heater system shall be individually
thermostatically controlled with adjustable setpoint between 66 to 121
degrees C 150 to 250 degrees F internal skin temperature, the minimum
specified ambient temperature, and shall be furnished and installed
complete including power, control, and alarm components. Heater voltage
shall be [_____] volts AC. Control voltage shall be 120 volts AC. Modular
heaters shall be furnished complete. Heater modules shall be
self-contained. The modules shall have a flexible heating face to conform
to the irregularities of the hopper surface, providing intimate contact
between the heaters and the hopper, and providing maximum heat transfer.
Hopper heaters shall be of low watt density design (maximum of three watts
per 645 square mm square inch of resistance element) with a minimum of six
parallel resistance paths per heater (continuous blanket type elements
shall be deemed to meet the multipath requirement). Each heating element
in the module shall be capable of being operated at 2152 watts per square
meter 200 watts per square foot. Heating elements shall be made of 600
series stainless steel alloy or nichrome encased in a 20 gage minimum
aluminum or aluminized steel mounting pan or casing. Cold lead wires and
interconnecting wires shall be multistrand copper wire with high temperature
(454 degrees C) (850 degrees F) insulation. Cold leads shall be furnished
with strain relief constructed in such a manner as to prevent damage to the
heater modules due to rough handling. Leads shall be of sufficient length
to reach the terminal box. Splices shall not be permitted in leads from
modules, tapes, or blankets to the terminal box. Each module, blanket, or
tape shall be tested for electrical integrity at 1,000 volts prior to
installation. Individual modules shall be designed to fit between the
hopper stiffeners and other hopper well obstructions to provide the maximum
coverage possible. Heating units supplied shall have metal labels firmly
attached to the unit listing the wattage and voltage of the unit. Heating
units and mounting hardware shall be constructed of high temperature
materials capable of withstanding 454 degrees C 850 degrees F. Heating
units shall be insulated with high temperature woven glass cloth or mineral
fiber. Mica or magnesium oxide insulated heaters shall not be provided.
Cold leads from each heater shall be provided for external circuit
connection. The cold leads shall be contained in hot-dip galvanized NEMA
Type 4, as defined in NEMA ICS 6, cast iron fitting for connection to field
installed solid conduit or waterproof raceway. NEMA 4 as defined in
NEMA ICS 6 hopper heater terminal boxes with terminal blocks for connection
to heater leads and thermostat leads shall be provided. Terminal blocks in
each terminal box shall contain a sufficient number of terminals to connect
the heaters for each hopper, one control thermostat, and one low
temperature alarm thermostat. The thermostats for monitoring hopper
temperature shall be 120 volts AC adjustable type in NEMA 4 enclosures.
Each hopper heater terminal box, fed from a panel, shall include one 3-pole
fused main switch, magnetic contractor and alarm relay with two normally
open contacts, terminal blocks for power, control and alarm circuits, a
fused control transformer having a 120-volt secondary, and auxiliary relays
for automatic operation of the heater system. The cover shall have the
SECTION 23 51 43.00 20
Page 53
between any two holes on a side in the flange pattern after fabrications of
the complete ductwork section. After fabrication of the ductwork section,
measurement shall be made between holes across diagonals and bracing shall
be installed to maintain flange bolt tolerance. Provide connections for
temperature and pressure measurements as specified and as required of the
control of the FGD system. Instrument connections shall be 50 mm 2 inch
Schedule 40 pipe with screw caps and shall extend 150 mm 6 inches beyond
the insulation and lagging on the ductwork. Instrument connections shall
be provided with rod-out caps or plugs. Maximum plan width inside
dimension of the breeching at interface with the chimney shall be [_____].
2.11.1.1
Reverse Air Ductwork
Reverse air ductwork shall be constructed of sheet steel and all seams and
connections shall be airtight. Means shall be provided to maintain the
temperature in the reverse air ductwork above the dewpoint by circulation
of clean flue gas.
2.11.2
Expansion Joints
**************************************************************************
NOTE: Dry and Wet Bulb Temperature and Duration:
Parameter
Season
Temperature (Degrees C)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Wet Bulb
Jun-Sep
[_____]
[_____]
Season
Temperature (Degrees F)
Frequency of Occurrence of
Higher Temperatures
Dry Bulb
Dec-Feb
[_____]
[_____]
Dry Bulb and
Mean
Coincident
Wet Bulb
Jun-Sep
[_____]
[_____]
Wet Bulb
Jun-Sep
[_____]
[_____]
Parameter
**************************************************************************
Expansion joints shall be nonmetallic belt-type joints. Expansion joints
shall be suitable for maximum expected or specified working pressures and
for operation at design gas-flow velocities. Expansion joints shall
include baffles able to withstand a fallout ash weight of 976 kg/sq m 200
lbs/sq ft and remain completely workable. Expansion joints shall be
designed for temperature from [_____] to [_____] degrees C degrees F.
Provide access to four sides of expansion joints, both interior and
SECTION 23 51 43.00 20
Page 75
exterior to the ductwork. Each expansion joint shall include: minimum 80
by 80 by 6 mm 3 by 3 by 1/4 inch carbon steel angle flanges drilled for
mounting to ductwork for joints where belt does not have molded flanges, a
carbon steel backing bar, and internal baffle around full circumference of
expansion joint; minimum of 3 mm 1/8 inch thick to prevent fly ash erosion
and buildup in web of joint and not restrict the movement of the joint, and
nuts and bolts required to attach the fabric to the flanges and the
expansion joints to the ductwork. Bolt holes on maximum of 100 mm 4 inch
centers. Belt materials shall be minimum 6 mm 1/4 inch thick, two-ply,
aramid-or fiberglass-reinforced, solid fluoroelastomer polymer specially
compounded for the intended service. Material shall be factory spliced to
form endless belt without sewn joints. Bolt holes shall be factory punched.
2.11.3
Dampers
Dampers shall be designed for a Zone [_____] seismic risk area and a wind
loading and additional loads as specified. The dampers shall be designed
to be operated without manual assistance under temperatures and pressures
specified and with normal accumulations of flue products. Dampers shall
have provision for periodic lubrication with appropriate grease, if not
permanently lubricated and sealed. Dampers shall be supplied with limit
switches which shall give positive indication of the damper position
(open/close). Dampers except guillotine dampers shall have pneumatic
operators. Guillotine dampers shall be provided with the manufacturer's
standard motor operators as required for the service intended. Dampers
shall fail in failsafe position upon loss of power or air. Fabric filter
baghouse bypass dampers shall be a double tight seal damper to provide for
essentially zero leakage at maximum fabric filter baghouse design
differential pressure. Bypass dampers shall be provided with an air
reservoir of sufficient capacity as to activate damper upon loss of plant
air. Inlet and outlet dampers shall be a minimum of 99 percent gas tight.
Fabric filter baghouse module inlet and outlet damper operators shall be
located outside of the gas stream and shall be accessible for maintenance
with the unit in operation. Induced draft fan inlet control dampers shall
be louver dampers in accordance with induced draft fan manufacturer's
recommendations. Guillotine isolation dampers at stack inlet breeching
shall be provided with control interlocks to prevent dampers from closing
when the associated induced draft fan is operating. Provide positive means
of preventing accidental closure of guillotine dampers. These dampers will
be used to isolate the equipment upstream for maintenance. They shall be
equipped with an external, locally-mounted audible alarm to signal loss of
seal air for personnel safety. Each damper frame shall be of a rigid
structural design to eliminate distortion or warpage which may interfere
with the damper operation. Frames shall be flanged for bolting to
connecting ductwork. Frames shall be designed to support a fly ash load of
1464 kg/sq m 300 lbs/sq ft on the bottom of the frame. Design frames to
support a 908 kg 2,000 pound concentrated load due to uneven fly ash
distribution, at a point that causes maximum deflection of the frame.
Frames shall be designed to support the seal air fan system, related
controls, motors, and drive mechanisms, and the entire damper unit with
only one flange bolted to the ductwork. Include lifting lugs to ensure
proper handling of the damper during transportation and erection. Frames
on louver dampers shall be of a length greater by one inch than the width
of the louver blades. Control drive units shall be as specified and shall
provide a direct position readout at the damper by means of a mechanical
position indicator showing percent of damper opening on flow control
dampers. Control drives other than poppet damper actuators shall be
equipped with a permanently mounted handwheel that is disengaged under
conditions of pneumatic or motor operation.
SECTION 23 51 43.00 20
Page 76
finish.
2.9.1
Lime Storage and Feed Bin
The lime preparation system shall have an integral storage and feed bin for
pebble lime. The bin shall be shop fabricated, all welded construction of
carbon steel plate with a minimum thickness of 6 mm 1/4 inch, conforming to
ASTM A36/A36M. The bin shall be structurally supported as necessary to
provide for enclosed areas for equipment levels directly beneath the bin
cone hoppers. The lime preparation system structure shall be designed for
wind, snow, seismic and other loads, as specified in paragraph entitled
"Structural and Miscellaneous Steel." Structural design shall be based on
a bulk density for pebble lime of 1040 kg per cubic meter 65 pounds per
cubic foot. Bin diameter shall be 3.70 meters 12 feet. Bin height shall
be based on pebble lime bulk density of 880 kg per cubic meter 55 pounds
per cubic foot and angle or repose of 55 degrees. Bin shall be cylindrical
with twin, 60 degree minimum conical bottom hoppers. Roof shall be sloped
1:12 for drainage. The roof shall have an inlet target box located at the
center and provisions for mounting the bin vent filter, pressure relief
valve and high-level switch. Provide for access to the interior of the bin
from the roof through a hinged manway. Access, handrails, and kickplate
for the roof shall be provided as specified in paragraph entitled
"Structural and Miscellaneous Steel." A fill pipe shall be provided for
transporting pebble lime from self-unloading trucks to the storage and feed
bin. The fill pipe shall extend from the truck fill connection point,
approximately 1.22 meters 4 feet above grade, to the center fill collar.
The fill pipe shall be 100 mm 4 inch O.D. Schedule 40 carbon steel pipe. A
1219 mm 4 inch centerline radius bend shall be used for the direction
change at the top of the fill tube riser. The fill tube shall be complete
with a quick coupling hose connection with security chain, dust cap and
limit switch at the truck connection point and a clean-out cap at the inlet
target box. The inlet target box shall be provided with two openings for
fill piping connections: One for use with the 100 mm 4 inch fill pipe to be
provided under this contract and one for use with the pneumatic conveying
system piping to be provided by the Contractor. The opening for use by the
pneumatic conveying system piping shall be 150 mm 6 inches in diameter and
shall be suitable for attachment of a reducer for compatibility with the
conveying line size selected later for use with the pneumatic conveying
system. Provide a bin vent filter for mounting on top of the bin, with
retained dust discharge directly into storage bin. This unit shall have a
venting capacity of at least 472 L/s 1,000 scfm. Filter bags must be
readily removable for inspection or replacement without tools.
Construction of filter manifold shall prevent filter bags from falling into
storage bin. Operation of the filter shall be such that there will be no
escape of dust during truck unloading. Filter unit shall be fabricated
weatherproof and dripproof construction, with self-contained bag cleaning
system and fan assemblies. Weather and dripproof gasketed access doors to
bag compartment shall be provided. Parts of unit subject to service or
maintenance shall be not more than 1 1/2 meters 5 feet above the bin roof
and shall be accessible by a person standing on top of the bin without use
of ladders or platforms. The bin filter exhaust fan shall be the
squirrel-cage type, operating at less than 3,500 rpm, with mounting on the
bin vent filter. This unit shall have air handling capacity of at least
472 L/s 1,000 scfm. It shall provide a negative pressure within the bin
during unloading operations. The fan outlet shall be provided with a
louvered damper which automatically opens during operation and closes when
the bin is not being filled and shall be fitted with a removable bird and
insect screen. Electric connections shall be NEMA 3R, rainproof. A
disconnect switch in NEMA 3R steel enclosure shall be provided and mounted
SECTION 23 51 43.00 20
Page 56
on the vent filter unit to allow local shutoff of power supply to
electrical devices located at the bin roof level. Wiring connections to
these units shall be made by the Contractor. Two bin level switches shall
be mounted at a high and at a low level on the bin. These switches are to
be of the stainless steel, rotating-paddle type, electrically operated.
Indicating lights coincident with these switches shall be provided in both
the truck unloading panel and the main control panel. Top-mounted units
must have extension shafts and guards. Side-mounted units shall be provided
with inside shields and all units must be mounted adjacent to ladders or on
top of storage bin. The lower bin switch shall be located to represent
capacity in terms of complete truck loads of material, based on truck load
capacity of 18.82 cubic meter 665 cubic feet per load of quicklime density
at approximately 960 kg per cubic meter 60 pounds per cubic foot. One
heavy-duty vibrator shall be connected to the outside of each bin cone and
provided with suitable controllers and timers to allow pacing from the
quicklime feeder. Each vibrator shall be interconnected with the
associated feeder, in order that it operates in proportion to feed rate
only when the bin gate is open and the feeder operates. Live bottom type
bin dischargers may be provided in lieu of the outside vibrators. A
manually-operated, dust-tight slide gate shall be mounted at the
termination of each bin cone to allow isolation of the equipment below for
maintenance.
2.9.2
Lime Slakers
The lime slakers shall be of the detention or paste type. The slakers
shall be designed for continuous operation at the required capacity.
Slaking temperature and slaking performance shall be automatically
maintained, so that at least 90 percent of the calcium hydroxide particles
formed are smaller that 2 microns in size, when lime quality is as
specified. Slakers shall be capable of slaking all grades of 20 mm 3/4 inch
pebble quicklime at a controlled temperature. Automatic controls shall be
provided to inject excess water into the slaking chamber should the
temperature exceed a preset limit. Slakers shall be provided with an
exhaust system to prevent water vapor from rising into the feeder
mechanism. The slakers shall be of all welded steel construction and shall
be completely dust-tight. Access covers for all compartments shall be
provided. Slakers shall be designed for ease of maintenance and shall be
capable of shutdown for up to 24 hours without requiring cleanout prior to
restart. Provide a hose connection at each slaker level for use by
maintenance personnel. Lime feeders shall be of the gravimetric or
volumetric type as required for compatibility with the lime slakers.
Feeders shall be designed to prevent flooding of the slakers with lime.
Feeders shall be capable of handling pebble quicklime, including fines.
Feeders shall be dust-tight and shall be provided with dust-tight,
stainless-steel inspection doors on the discharge side of the feeders.
Flexible connections shall be provided between the bin cone outlets and the
feeders. Feeders shall be provided with adjustable rate setters and
totalizers. Each lime slaker shall be provided with a positive means of
removing grit from the lime slurry prior to discharging the slurry to the
tank. The grit removal system shall include classifiers or screens or both
as required to remove any grit which could produce operational problems in
the slurry pumps, piping, valves, or atomizers. The grit removal system
shall include a means of rinsing the grit with water to minimize lime
carryover to the grit disposal bin. The degritted slurry shall flow by
gravity to the slurry tank. The grit shall be conveyed to a disposal bin
(bin provided by the Government) located on the lower level within the lime
system enclosure at a point accessible to a forklift truck. The Contractor
shall provide conveyors and chutes as necessary to discharge grit to the
SECTION 23 51 43.00 20
Page 57
disposal from a point not more than 1.83 meters 6 feet above the lower
level floor. A slurry storage tank shall be located beneath the slakers in
the lime system enclosure. The tank shall be constructed of 6 mm 1/4 inch
carbon steel. The slurry tank shall be designed with a minimum storage
capacity of one hour at the maximum slurry use rate. The tank shall be
covered to minimize contact of the slurry with air. The tank shall be
provided with heavy-duty, top-mounted turbine agitators of a quantity and
design as necessary to keep the slurry particles in uniform suspension
without vortex formation. Tank shall have internal baffles to promote
agitation. Agitators shall be interlocked with pump controls so that pumps
cannot start unless at least one agitator is on. The tank shall be
provided with level monitors required for proper system operation. Level
switches shall be electrode probe type. Bubbler-type level switches are
not acceptable. The tank shall be provided with all necessary inlet,
outlet, and overflow connections. The bottom of the tank shall be pitched
for drainage and provided with a cleanout easily accessible by maintenance
personnel. The Contractor shall provide additional slurry tanks as
required for his specific system design. Tanks furnished under this
contract shall be shop fabricated, all-welded construction of carbon steel
with a minimum shall thickness of 6 mm 1/4 inch. Structural design
requirements of paragraph entitled "Structural and Miscellaneous Steel"
including seismic design, are applicable to tanks furnished.
2.10
PUMPS, VALVES, MOTORS
Centrifugal pumps shall be used for applications for which unique flow and
head requirements necessitate the use of positive displacement pumps. The
general requirements specified in this paragraph shall be applicable to
pumps furnished except as specifically noted. Positive displacement pumps
furnished for use with lime slurry shall have a history of reliable
operation for that application at pilot plant or commercial installations.
Positive displacement slurry pumps for which shaft seals are necessary
shall be provided with mechanical seals which do not require the use of
seal water which could infiltrate into the slurry. Provide piping, valves,
and fittings required to connect the spray dryer absorbers, lime slurry
preparation system, fabric filter baghouses, pumps, and tanks complete with
hangers and connection for instruments, vents, flushing, and drains as
required. Provide properly sized bypasses for equipment and control
valves. Instrumentation and controls shall be as specified in paragraph
entitled "Instructural and Controls." Piping materials and fabrication
shall conform to ASME B31.1 (Power Piping Code). Furnish alternating
current high efficiency electric motors required to drive the equipment
furnished under this Contract. Provide each pump assembly with the
manufacturer's standard finish. Protect exposed machine surfaces with a
rust-preventative compound. Cover flanged openings with plywood covers
held by a minimum of four bolts. Plug or cap screwed connections with
standard fittings.
2.10.1
Pumps
Furnish the pumps required or specified complete with motor drives,
accessories, and field service. Provide 100 percent installed spare
capacity for pumps. Provide water pumps for slaking water and cooling
water supply as shown on the process flow diagram. These locate pumps at
the water storage tanks to be provided by the Contractor. For purposes of
the proposal, these tanks shall be assumed to be located at grade at a
distance of 18.30 meters 60 feet from the piping interface point
indicated. Contractor shall provide piping from these tanks to the points
of application within his system. Each pump assembly shall include pump,
SECTION 23 51 43.00 20
Page 58
driving motor, baseplate, drive coupling or multiple V-belt drive, and
coupling guard, as applicable. Include dowelling of pumps to baseplate.
Each pump shall be of a design and construction for service intended.
Overhead motor mounting structure shall have provision for drive belt
tension adjustment. Structure shall be such that motor and mounting are
supported independently of the pump bearing assembly. Provide structure to
allow for removal of pump bearing assembly without disturbing the motor.
Structure shall be of fabricated steel, and shall provide support for
V-belt drive guard. Drive couplings and matched multiple V-belt drive
(MVD) sets shall be rated at not less than 140 percent of the motor power.
Guard for matched MVD sets shall have solid metal cover on pump side and
expanded metal mesh on outboard end. Flexible drive coupling guards shall
comply with applicable safety requirements. Flexible coupling guards shall
be arranged for ease in disassembly or removal for access to couplings.
Coupling guards shall be rigidly fastened to baseplate. Prevent any
external thrust from being transmitted to the motor shaft under any
operating conditions. Provide double-screw adjustment bases on
nonadjustable horizontal arrangements. Suction and discharge connections
shall be standard Class 150 ANSI flat-faced flanges, rubber lined, if pump
is rubber lined. Furnish drawings and data as specified in paragraph
entitled "Submittals." Include in submittals information for the general
arrangement and outline, instrumentation, piping connection, electric
motors sound pressure ratings, description of flushing system for slurry
pumps, and performance curves.
2.10.1.1
Centrifugal Pumps
Pump speed shall be such that the upper limits of specific speed, as
defined by the applicable figure of the HI M100 are not exceeded at any
pump operating condition. Total dynamic head of pumps shall be maximum at
zero flow and continuously decreasing from zero flow to design flow. Head
capacity characteristics shall permit stable operation when pump is
operating alone or in parallel with other pumps of the same designation.
Pump shut-off head shall be more than 110 percent of design point head and
less than 150 percent of design point head. Pump shaft critical speeds
shall not occur from 10 percent of design point head. Pump shaft critical
speeds shall not occur from 10 percent to 120 percent of design rpm. Pump
shaft shall be free from excessive vibration at discharge rates from 10
percent to 120 percent of design delivery. Impeller shall not be maximum
or minimum size for pump casing furnished to allow for possible future
modification of head capacity furnished to allow for possible future
modification of head capacity characteristic by changing impeller size. The
maximum allowable sound pressure level shall be 84 dB for each pump-motor
unit. Slurry pumps shall be vertically split-case, rubber-lined
single-stage pumps designed for indoor service. Water pumps shall be
vertically split-case single-stage pumps designed for outdoor service.
Slurry pumps shall be provided with shaft seals which do not require water
flushing. Provide water pumps with mechanical shaft seals which do not
require an external source of seal water. Pumps shall be provided with
flexible inlet and outlet connections.
2.10.1.2
Vertically Split-Case Rubber-Lined Pumps
Vertically split-case rubber-lined pumps shall be end suction,
single-stage, single-suction centrifugal, of the volute type. Pump trim
shall be stainless steel suitable for the service and designed for
continuous operation at specified operating conditions. Pumps shall be
frame mounted with pump shaft carried on its own bearings with multiple
V-belt drive between pump and motor. Pumps shall have bottom horizontal
SECTION 23 51 43.00 20
Page 59
discharge. Pump casing shall be split vertically into suction inlet
assembly and pump assembly designed for ease of disassembly. Casing shall
have replaceable secured rubber liner, minimum 10 mm 3/8 inchthick designed
for long life under operating conditions specified. Pump impeller shall be
enclosed type, of soft natural rubber on steel skeleton. Pump shaft shall
be provided with ceramic faced shaft sleeves designed to prevent water
leakage between shaft and sleeve. Sleeve shall be adequately anchored to
the shaft to prevent any rotation of the sleeve relative to the shaft.
Shaft shall be keyed on the driven end for easy removal of the coupling
half. Shaft shall be completely encased along its entire length within the
wetted area by the impeller and shaft sleeves. Provide adequate fillets
for changes in diameter. Pump bearings shall consist of two bearing
assemblies, ball or tapered type roller type, mounted in an oil-filled or
grease-lubricated housing. Provide adequate seals to prevent leakage of
lubricant to outside and dust entry to inside of housing. Bearings shall
have 60,000-hour minimum B-10 life under design conditions in accordance
with ABMA 9 and ABMA 11. Design to limit maximum shaft deflection to 0.05
mm 0.002 inch. Provide with lubrication system consisting of a
constant-level oiler with level indicator or easily accessible grease
nipples as appropriate to the bearing design. Provide mechanical or
centrifugal shaft seals conforming to paragraph entitled "Centrifugal
Pumps." Furnish one spare set of shaft seals for each pump. Support
frames for all vertically split pumps shall be fabricated of structural
steel and heavy plate extending the full length of pump and driver. Design
to adequately support equipment under operating conditions without grout
fill inside the frame. Frame shall not be covered with a thin steel plate
which requires grouting under the plate, but the frame may be filled with
concrete as required for drainage. Grout shall be required under the basic
frame only. Contractor to provide minimum 25 mm one inch pipe drain in the
perimeter of the frame. Drawings shall indicate the required concrete fill
lines for proper drainage. The pump shall be dowelled shall be dowelled to
the frame in the shop; the driver shall be dowelled in the field. Furnish
bolts or screws for attaching pumps and motor drives to the support frame.
Frames shall have grouting holes, 100 mm 4 inch minimum size, to facilitate
proper grouting, if area is covered. Materials of construction shall be as
specified below.
Part Name
Material
Casing
Cast iron or steel, ASTM A48/A48M with replaceable
rubber liners
Impeller
Soft rubber on steel skeleton
Shaft
Heat-treated carbon, or stainless steel,
ASTM A276/A276M, Type 410
Shaft Sleeve
Ceramic faced
Baseplate Steel
ASTM A36/A36M
2.10.1.3
Vertically Split-Case Pumps
Vertically split case pumps shall be end suction, single-stage,
single-suction centrifugal, of the volute type. Pumps shall be bronze
trimmed, and designed for continuous operation at specified operating
conditions. Pumps shall be frame-mounted with pump shaft carried on its
own bearings with flexible coupling between pump and motor. Pump
orientation to fit piping arrangement. Pump casing shall be split into
suction inlet assembly and pump assembly. Design for ease of disassembly,
SECTION 23 51 43.00 20
Page 60
allowing the rotating assembly and bearing housing to be removed without
disconnecting pipe or moving the motor. Provide renewable casing rings
locked against rotation, with one ring mounted in suction inlet assembly
and the other ring mounted in pump assembly. Provide with casing vent and
drain connections. Pump casing shall be back pull out design. Pump
impeller shall be enclosed type, fully machines throughout. Axial balance
shall be obtained by balancing ports and rear sealing rings. Casing and
impeller wear rings shall be of different hardness designed for long
wearing qualities. Pump shaft shall be provided with shaft sleeve designed
to prevent water leakage between shaft and sleeve. Sleeve shall be
anchored to the shaft to prevent any rotation of the sleeve relative to the
shaft. Shaft shall be keyed on the driven end for easy removal of the
coupling half. Shaft shall be completely encased along its entire length
within the wetted area by the impeller and shaft sleeves. Provide adequate
fillets for changes in diameter. Design to limit the maximum shaft
deflection at the stuffing box to 0.05 mm 0.002 inch. Pump bearings shall
consist of two bearing assemblies, tapered-roller type, mounted in an
oil-filled housing. Provide adequate seals to prevent leakage of oil to
outside and dust entry to the inside. Bearings shall have 60,000 hour
minimum B10 life under design head conditions. Bearing loading for thrust
determination shall be at the most adverse operating condition of the
pump. Provide with oil lubrication system including oil level indicator.
Seals shall be single, mechanical type of the inside, balanced design.
Seal face materials shall be selected to provide long life in the service
intended. Factory-installed seal water piping shall be provided from pump
discharge to inlet connection on seal housing as required to cool and
lubricate the seal faces. Seal water loop shall include a valve or orifice
to control flow. Provide a spare seal for each pump. Support frames for
vertically split pumps shall be fabricated of structural steel and heavy
plate extending the length of pump and driver, rigid enough to maintain
alignment of machinery, and designed to adequately support equipment under
all operating conditions without grout fill inside of the frame. Frame
shall not be covered with a thin steel plate which requires grouting under
the plate, but the frame may be filled with concrete as required for
drainage. Grout shall be required under the basic frame only. Contractor
to provide one inch minimum drain in the perimeter of the frame.
Drawings
shall indicate the required concrete fill lines for drainage. The pump
shall be dowelled to the frame in the shop, the driver will be dowelled in
the field by others. Furnish bolts or screws for attaching pumps and motor
drives to the support frame. Frames shall have grouting holes, 100 mm 4
inch minimum size, to facilitate proper grouting. Materials of
construction shall be as specified.
Part Name
Material
Casing
Cast iron or steel, ASTM A48/A48M with replaceable
rubber liners
Impeller
Bronze, ASTM B584
Shaft
Heat-treated carbon, or stainless steel,
ASTM A276/A276M, Type 410
Shaft Sleeve
11-13 percent chrome steel, 450 minimum Brinell
hardness, ASTM A743/A743M
Casing rings
Bronze, ASTM B103/B103M
SECTION 23 51 43.00 20
Page 61
Part Name
Material
Impeller rings
Bronze, ASTM B103/B103M
Baseplate Steel
ASTM A36/A36M
2.10.1.4
Vertical Wet Pit Pumps
Vertical wet pit pumps shall be end suction, single-stage, single-suction
centrifugal of the volute type. Pump trim shall be 316L stainless steel
designed for continuous operation at specified operating conditions. Pumps
shall be frame mounted with pump shaft carried on its own bearings with
multiple V-belt drive between pump and motor. Provide suitable connections
on the frame for lifting and lowering of the pump. Pump casing, pipe shaft
column, discharge piping, and submerged materials, shall be rubber-coated a
minimum of 6 mm 1/4 inch thick. Pump casing shall be split perpendicular
to shaft. Provide renewable impeller wear rings locked against rotation.
Casing shall have replaceable rubber liner, minimum 10 mm 3/8 inch thick
designed for long life under operating conditions specified. Casing shall
be rubber covered. Pump impeller shall be enclosed type of soft natural
rubber on steel skeleton. Pump shaft shall be provided with hardened
(minimum 450 BHN) stainless-steel shaft sleeves designed to prevent water
leakage between shaft and sleeve. Sleeve shall be adequately anchored to
the shaft to prevent any rotation of the sleeve relative to the shaft.
Shaft shall be keyed on the driven end for easy removal of the coupling
half. Shaft shall be completely encased along its entire length by the
impeller and shaft sleeves. Shaft shall have fillets for changes in
diameter. Shaft shall be designed to carry torsional and axial thrust
loads. Shaft shall be one-piece construction. Shaft support column shall
be rubber covered. Upper bearing assembly shall be ball or tapered-roller
type, mounted in an oil-filled or grease-filled housing. Include adequate
seals to prevent leakage of lubricant to outside and dust entry to the
inside. Bearings shall have 60,000-hour minimum B10 life under design head
conditions. Provide with adequate lubrication system. Provide with dust
and oiltight seals. Pump shall have no submerged bearings. Provide shaft
seals as specified in paragraph entitled "Vertically Split-Case
Rubber-Lined Pumps." Pump baseplate shall be of fabricated steel, of
adequate size and thickness to prevent excessive vibration and deflection.
Provide holes for mounting of the pump and necessary piping as required.
Baseplate shall be rubber-coated on the bottom side. Provide with shims,
bolts, and other devices required for proper alignment and anchorage.
Anchor bolts required in foundation will be furnished by the Contractor.
Materials of construction shall be as specified below.
Part Name
Material
Casing
Cast iron or steel, ASTM A48/A48M rubber covered with
replaceable rubber liner
Impeller
Soft rubber on steel skeleton
Shaft
Heat-treated carbon, or stainless steel,
ASTM A276/A276M, Type 410
SECTION 23 51 43.00 20
Page 62
directly related to the rate of lime feed to the atomizer. The lime slurry
feed rate to the atomizer shall be regulated by a control valve which is
modulated by a signal from the analog control system utilizing an input
from an sulfur dioxide analyzer located at the fabric filter baghouse
outlet. The control valve shall fail closed on loss of air, power, or
control signal and the control system shall be provided with sufficient
interlocks so that FGD system upsets cannot result in excessive liquid feed
and subsequent moisture carryover to the fabric filter baghouse. The
control system shall be designed to automatically control the sulfur
dioxide concentration leaving the fabric filter baghouse at a level set by
the operator from an operating station in the control room. Provide
continuous indication of the inlet and outlet sulfur dioxide concentration,
control valve status and slurry feed rate on the main control panelboard.
The temperature of the flue gas leaving the absorber shall be controlled to
an operator-adjustable setpoint by automatic regulation of water feed to
the atomizer. The water feed rate to the atomizer shall be regulated by a
control valve which is modulated by a signal from the analog control system
utilizing an input from a temperature transmitter located at the spray
dryer outlet. The control system shall provide a means of assuring that
the outlet temperature remains above the moisture dewpoint with an adequate
margin of safety as required to prevent condensation at any point
downstream in the FGD system. A control signal will be available to
indicate the initiation and termination of the steam sootblowing cycle. The
temperature control system shall make use of this signal to automatically
compensate for the additional moisture input with the flue gas. The water
control valve shall fail closed on loss of air, power, or control signal.
Absorber inlet and outlet temperature, water control valve status, and
water feed rate shall be indicated at the main control panelboard. Each
atomizer shall be provided with a local control panel mounted in the
penthouse enclosure. Complete local controls, indicating lights and alarms
shall be provided. Controls for the two-fluid nozzle atomizers shall be as
follows: interlocks and automatic trips shall be provided to automatically
stop the atomizer due to low oil pressure, high oil temperature, high motor
temperature or high vibration level. Remote indication of atomizer
operating conditions and alarms shall be provided on the main control
panelboard. Atomizer start switches shall be provided both locally and
remote.
2.12.1.3
Baghouses
Primary control of the fabric filter baghouses shall be from the FGD system
panelboard located in the steam plant control room. Design the control
system for automatic control of each fabric filter baghouse as required to
ensure stable and reliable operation. Monitor status and position of
motors, dampers, valves, etc. at the main control board by a graphic
presentation. Design for automatic or manual start-up and automatic
verification of the operation of each component of the fabric filter
baghouse in sequence as required for proper operation of the system. The
automatic start-up sequence will be manually initiated. Design for
automatic or manual shutdown and automatic verification of the shutdown of
each component of the fabric filter baghouse in sequence as required for
proper shutdown of the system. Design for automatic and safe shutdown of
any malfunctioning part of the system without disrupting boiler operation
capabilities. Any effect on the steam plant due to system control changes
will be avoided or minimized. The cleaning cycle will be initiated by
measurement of pressure drop across total fabric filter baghouse, by timer,
or by manual switch. Initiation mode shall be switch selectable. A manual
selector switch will allow manual operation of the cleaning function for
any module for the purpose of extra cleaning of any module or in the event
SECTION 23 51 43.00 20
Page 87
of automatic sequence failure. Off-line cleaning of pulse-jet fabric
filter baghouse modules (normal) or on-line cleaning shall be available at
the selection of the operator. The automatic timer and manual selector
switch will be interlocked with an isolation switch located at the tube
sheet access doors to ensure isolation of the module for maintenance. The
automatic timer will bypass any module not in service. This bypass will be
accomplished without timing through the cleaning cycle for the module just
bypassed (no dead time). The cleaning timer will allow for adjustment of
the frequency and duration of cleaning cycles to obtain optimum bag
cleaning. The bypass mode selector for each fabric filter baghouse will be
functional for either automatic control and for manual control. The system
shall automatically bypass the fabric filter baghouse as required to
prevent moisture carryover from spray dryer. Monitor status of process and
equipment for abnormal operation, failure, trip, etc. and provide visual
and audible alarms. Alarm indication shall include, but not be limited to,
high temperature drop across the fabric filter baghouse, high-pressure drop
across fabric filter baghouse, cleaning system malfunction, high ash level
(with indication of which hopper is alarming) and low hopper temperature
(with indication of which hopper is alarming).
Graphic display shall include at a minimum the following indicating lights
(color of lens in parentheses):
a.
Inlet damper--OPEN (green).
b.
Inlet damper--CLOSED (red).
c.
Outlet poppet--OPEN (green).
d.
Outlet poppet--CLOSED (red).
e.
Module--ACTIVE (green).
f.
Module--INACTIVE (red).
g.
High ash level (red)*.
h.
High inlet gas temperature (red)*.
i.
Low compressed air pressure (red)*.
j.
High system differential pressure (red)*.
k.
Power--ON (red).
l.
SYSTEM START (green).
m.
SYSTEM STOP (red).
n.
Cleaning mode OFF-LINE selected (white).
o.
Cleaning mode ON-LINE selected (white).
*These items shall activate an audible alarm.
Two position selector switches shall be provided for the following.
a.
Power--ON/OFF.
SECTION 23 51 43.00 20
Page 88
b.
Module--ACTIVE/INACTIVE.
c.
Cleaning mode--OFF-LINE/ON-LINE.
Momentary contact push buttons shall be provided for the following.
a.
System--START (green head).
b.
System--STOP (red head).
c.
Alarm--ACKNOWLEDGE.
Provide auxiliary devices required for the control functions indicated
including the following.
a.
Position indication switches on isolation valves.
b.
Hopper level alarms.
c.
Temperature indicator and thermocouple.
d.
Pressure switch.
e.
Audible alarm.
f.
Differential pressure gage (baghouse module and panel board).
g.
Fan current.
h.
Fan inlet static pressure.
i.
Fan outlet static pressure.
j.
Opacity.
Provide suitable laminated plastic nameplates for devices on panel face.
Temperature controller and differential pressure gage shall be mounted on
face of panel. In addition, provide a two pen, 250 mm 10 inch diameter
circular chart recorder to record inlet gas temperature and pressure drop
across baghouse system for each module. Differential pressure gage for
each module shall be indicating type with diaphragm magnetically coupled to
pointer mechanism.
Units shall include a programmable controller which shall be completely
solid state and shall be preprogrammed to control the following.
a.
Pulse duration (pulse-jet only).
b.
Pulse sequencing (pulse-jet only).
c.
Cleaning cycle time.
d.
Settling time.
e.
Module isolation valve control.
The system shall sense differential pressure between inlet and outlet of
each baghouse. When the differential pressure reaches the setpoint,
controller shall initiate cleaning of all modules. In addition, an
SECTION 23 51 43.00 20
Page 89
overriding timer shall be provided so that the bags can be cleaned on a
preset interval independent of pressure differential. (Pulse interval and
duration), cleaning cycle time, setting time and time for valve operation
shall all be adjustable. Differential pressure setpoint shall also be
adjustable.
2.12.2
Analog Control Systems
Furnish an analog control system complete with transmitters, flow-measuring
elements, control modules, control system cabinets and panelboard, control
operating stations, prefabricated plug-in cables, signal converters,
control drives and accessories as required to allow control of the FGD
system from the central steam plant control room. The control systems and
instruments shall be electronic and be designed for continuous operation.
The control system shall be of the "split architecture" design where
computing and logic modules are mounted in system cabinets. Operating
stations shall be mounted in the panelboard and connected to the system
control module racks, mounted in the system cabinets, using prefabricated
cables.
2.12.2.1
Electronic Control Modules
Analog computing and logic modules shall use proven solid-state electronic
design. Circuits shall be constructed with high-quality, pretested
components making maximum use of integrated circuits. Components shall be
readily available from known suppliers. Analog computing and logic modules
shall be designed for plug-in rack mounting in the system cabinets. Module
pins and mating connectors shall be gold plated on nickel to withstand
chemical attack by ambient atmospheric chemicals. Modules of the same type
shall be interchangeable to facilitate maintenance and trouble-shooting by
substitution. Pretest and age each module before installing in the module
racks. Factory assemble, wire, and test the system using the operating
stations and actual plug-in cables for the system. Provide input and
output test jacks on each module for tests. Controllers and analog
computing circuits shall perform as follows unless specifically noted
otherwise for a particular system or control loop: Provide calibrated,
front-mounted controls on appropriate modules, to adjust proportional,
integral and derivative action. Adjustments shall be possible while
operating in automatic without causing undesirable upsets such as a
proportional step. Prevent reset windup action and design to develop
response to demand without the system first performing internal controller
balancing. Provide means to automatically balance each loop that has a
manual-automatic operating station so that bumpless transfer may be made
from manual to automatic and from automatic to manual without any
intermediate manual balancing. Where both master stations and individual
final control element stations are employed in a loop, the master, as well
as individual stations shall transfer bumplessly and without balancing, and
be tied together, as appropriate. Bumpless transfer is effected if the
output signal to the final control element does not vary more than 2
percent of the full-scale output signal range when transferring from
automatic to manual and from manual to automatic. Provide for all
interlocks and contact inputs and outputs and all digital logic functions
necessary to control or interface the analog circuits throughout the
system. Provide signal monitor modules to track analog signals where
required to produce contact outputs for alarm or interlock with other logic
when the signal exceeds a predetermined level. Signal monitor units shall
be equipped with independently adjustable high and low set points. Provide
suitable isolating devices such as relays or optical couplers to protect
the control system from external outputs or inputs. Provide indicating
SECTION 23 51 43.00 20
Page 90
b.
Pipe clamps shall be carbon steel.
c.
Clevises, turnbuckles, and eye nuts shall be forged steel.
d.
Eye rods shall be welded type.
e.
Protection saddles shall be carbon steel.
f.
Hanger rod components located outdoors shall be galvanized with the
exception of lugs and clips welded directly to pipes or structural
members.
Pipe hanger assemblies, anchors, and sway braces shall utilize only
acceptable type of components as outline in MSS SP-58 and MSS SP-69. Upper
supports shall utilize types 22, 28, 29, and 33. Intermediate supports
shall utilize types 13, 14, 16, 17, 51, 52, 53, 54, 55, and 56. Lower
supports shall utilize types 2, 3, 4, 8, 24, 33, 35, 36, 37, 38, 39A, 39B,
40, 41, 44, 45, 46, 47, and steel plate lugs shop welded to the pipe.
2.10.2.5
Shipping and Handling
Materials for piping systems shall be prepared and marked for shipment and
storage as specified. Each piece of piping fabrication shall be identified
with a piece mark number which is repeated on each end of section and on
each branch. Ship gaskets to the jobsite tagged with size, material, and
pressure rating. Loose parts such as nuts, bolts, and gaskets shall be
packaged for outdoor storage. Protect flanges with plywood or tempered
hard fiberboard covers sealed and bolted to the flange with not less than
four bolts. Protect threaded connections with thread protectors. Protect
small connections with plastic inserts pressed into the connection and
sealed with waterproof tape. Ship hangers to the jobsite with each hanger
assembly individually bundled and tagged with the hanger assembly number.
Coat-threaded connections with a suitable rust-preventative compound. Ship
valves to the jobsite tagged with the appropriate valve number
corresponding to the valve list. Ship valves with suitable covers to
prevent entrance of foreign material into valve body. Protect valve
threads, stems, and handwheels from damage.
2.10.3
Electric Motor Drives and Motor Control Center
Alternating current electric motors required to drive the equipment shall
be continuous-duty type suitable for a steam plant environment where
moderately abrasive conductive dusts and high humidity are present. Motors
shall be self-ventilated. Motors shall be designed for full-voltage
starting. Indoor motors shall be suitable for continuous operation at an
ambient temperature of 50 degrees C 122 degrees F. Outdoor motors shall be
suitable for continuous operation at any ambient temperature from minus 10
degrees C to plus 40 degrees C 14 degrees F to 104 degrees F. Motors shall
have squirrel-cage rotors. The nameplate power rating of each motor at 1.0
service factor shall equal or exceed the power required to drive the
connected equipment under the design conditions specified and within normal
operating ranges. For each motor furnished, the nameplate power rating
multiplied by the service factor shall equal or exceed the power required
to drive the connected equipment under any operating condition. Motors
shall be of high efficiency type.
SECTION 23 51 43.00 20
Page 67
2.12.3.1
Wired Solid-State Logic
Components shall be highest quality industrial grade devices. Logic
elements shall be integrated circuits. Components shall be subjected to a
rigorous quality assurance inspection. Circuit cards shall be burned-in
and tested in the completed system a minimum of 170 hours continuous
operation. Logic elements shall be assembled on circuit cards to perform
specific operational functions. Different types of circuit cards shall be
minimized to reduce stocking of spares and to facilitate maintenance by
card substitution. Logic cards shall be arranged in functional groupings
for individual pumps or sequences. Failure of a single logic circuit or
compartment shall not affect more than one pump or separate functional
sequence. Power supplies shall be as specified for Analog Control Systems.
System electronics shall be buffered and protected from external power
sources by optical couplers or reed relays. Logic shall be documented by
logic diagrams.
2.12.3.2
Solid-State Programmable Logic
Components shall be highest quality industrial grade devices. Components
shall be subjected to a rigorous quality assurance inspection. Circuit
cards shall be burned-in and tested in the completed system a minimum of
170 hours continuous operation. Small systems requiring a minimum of
memory elements may use nonvolatile programmable memory. Larger systems
shall use software programmable memory with nonvolatile memory for program
and executive storage. Logic functions shall be performed by software
engineer. Logic shall be documented by flow charts or word logic, and by
program listings. Memory shall be static. Programming aids shall be
provided to permit easy field reprogramming. Battery power back-up may be
approved by the Contracting Officer. System electronics shall be buffered
and protected from external power sources by optical couplers or reed
relays. Software shall be factory tested and debugged including simulating
inputs and outputs and checking resulting logic sequences.
2.12.4
Flue Gas Cleaning System Panelboard and System Cabinets
Provide one common vertical panelboard and system cabinet sections, as
specified, to control the flue gas cleaning equipment for boilers.
Panelboard dimensions shall be 0.762 m deep by 2.44 m wide by 2.44 m high
30 inches deep by 96 inches wide by 96 inches high. No process fluids or
pneumatic signal lines shall be brought into any panelboard or system
cabinet.
2.12.4.1
Construction
Construct of 3 mm 1/8 inch hot-rolled steel panels reinforced with angles
and channels in the interior to form a single, rigid, freestanding unit in
compliance with NEMA 12. Panelboards shall be completely enclosed
floor-mounted units, except with bottom open. Panelboards shall be
constructed with no bolt heads or fastenings visible from the exterior.
Construct with 6 mm 1/4 inch radius corners. Edges shall be filled and
ground to conform to a 6 mm 1/4 inch radius. Provide interior innerpanels
for mounting auxiliary equipment and terminal blocks, as required. Make
provisions for anchoring to floor or foundation. Provide hinged doors on
the rear of the panelboard with key locks to allow access to equipment.
Provide lifting eyes and shipping pallet on the panelboard to facilitate
moving into the steam plant. Provide ventilation grills, exhaust fans,
ductwork, and filters, as required. Provide cutouts and removable cover
plates for items designated as future. Paint cover plates to match
SECTION 23 51 43.00 20
Page 93
Efficiency
Nameplate
3600 rpm
1800 rpm
1200 rpm
55.95
94.1
93.0
94.1
93.0
94.1
93.0
74.60
94.1
93.0
95.0
94.1
94.1
93.0
93.25
94.1
93.0
95.0
94.1
94.1
93.0
111.90
94.1
93.0
95.0
94.1
95.0
94.1
Efficiency
Nameplate
3600 rpm
1800 rpm
1200 rpm
Horsepower
Nominal
Minimum
Nominal
Minimum
Nominal
Minimum
1
81.5
78.5
84.0
81.5
78.5
75.5
1.5
81.5
78.5
84.0
81.5
84.0
81.5
2
84.0
81.5
84.0
81.5
86.5
84.0
3
86.5
84.0
88.5
86.5
88.5
86.5
5
88.5
86.5
90.2
88.5
88.5
86.5
7.5
88.5
86.5
90.2
88.5
88.5
86.5
10
88.5
86.5
90.2
88.5
90.2
88.5
15
90.2
88.5
91.7
90.2
90.2
88.5
20
91.7
90.2
91.7
90.2
91.7
90.2
25
91.7
90.2
93.0
91.7
91.7
90.2
30
91.7
90.2
93.0
91.7
91.7
90.2
40
91.7
90.2
93.0
91.7
93.0
91.7
50
91.7
90.2
94.1
93.0
93.0
91.7
60
93.0
91.7
94.1
93.0
93.0
91.7
75
94.1
93.0
94.1
93.0
94.1
93.0
100
94.1
93.0
95.0
94.1
94.1
93.0
125
94.1
93.0
95.0
94.1
94.1
93.0
SECTION 23 51 43.00 20
Page 69
Efficiency
Nameplate
3600 rpm
150
94.1
1800 rpm
93.0
95.0
1200 rpm
94.1
95.0
94.1
**************************************************************************
Motors shall be rated at 460 volts, 3 phase, 60 hertz, and have service
factor of 1.15 for open dripproof enclosures, and a service factor of 1.0
for all other enclosure types. Enclosures shall be fabricated of cast iron
or aluminum. Enclosures for indoor service other than in the lime slurry
preparation area shall be open dripproof, fully guarded. Enclosures for
the lime slurry preparation area, and for outdoor service shall be totally
enclosed nonventilated or totally enclosed fan cooled. Bearings shall be
antifriction type, and shall have an ABMA-L10 rating life of not less than
80,000 hours at rated speed, and under the thrust loadings encountered
within normal operating ranges. The thrust loading corresponding to an
ABMA-L10 rating life of 5,000 hours at rated speed shall not be exceeded
under any operating condition of the motor or the driven equipment.
Bearings shall be insulated when required to prevent bearing or shaft
damage due to stray shaft currents. Each horizontal motor shall be mounted
on a common baseplate with the driven equipment, or shall be furnished with
separate sole plates and subsole plates to permit removal of the motor
without disturbing the alignment of the driven equipment. Furnish space
heaters for motors rated 19 kW 25 horsepower and above. Space heaters
shall be rated 120 volts, single-phase, 60 hertz. The torque
characteristics of each motor at voltages from 90 to 110 percent rated
voltage shall be as required to accelerate the motor and driven equipment
to full speed without damage to the motor or the driven equipment.
Insulation shall be Class B or Class F, with Class B temperature rise in
accordance with NEMA MG 1. The motor "A" weighted sound level shall not
exceed 84 dBA when measured to conform to IEEE 85 at a reference distance
of one meter. Motors shall be of special high-efficiency and high-power
factor design including the following design features: Low-loss lamination
steel, increased stator and rotor length, increased winding cross section,
high-efficiency cooling fan design, and optimized slot configuration and
air gap. Information submitted with the compliance submittals shall
include minimum guaranteed efficiency based on tests performed in
accordance with IEEE 112, Method B, with accuracy improvement by segregated
loss determination including stray load loss measurement. Information
submitted shall include percent efficiency and percent power factor at full
load, 3/4 load, and 1/2 load. Provide motor bearing thermocouples and
motor winding resistance temperature detectors (RTDs) for motors 15 kW 20
horsepower and larger. Thermocouples and RTD's shall be as specified in
paragraph entitled "Temperature Monitor."
2.10.3.3
Motors Rated 150 Kilowatt 200 Horsepower and Larger
Motors shall be rated 4,000 volts, 3-phase, 60 hertz, have a service factor
of 1.0 and conform to NEMA C50.41. The torque characteristics of each
motor at voltages from 85 to 110 percent rated voltage shall be as required
to accelerate the motor and driven equipment to full speed without damage
to the motor or the driven equipment. Insulation shall be Class B or Class
F, with Class B temperature rise in accordance with NEMA C50.41. Insulation
systems shall be mica based. Each motor shall be furnished with not less
than two resistance temperature detectors per phase, embedded in the stator
windings. Detectors shall be rated 10 ohms at 25 degrees C as specified in
SECTION 23 51 43.00 20
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paragraph entitled "Temperature Monitor." The acceleration times for each
motor at voltages within the starting voltage specified, when connected to
the driven equipment, shall not exceed the allowable locked-rotor times at
those voltages. In addition to the starting capabilities specified in
NEMA C50.41, following one start with the motor initially at a temperature
equal to the rated-load operating temperature, each motor shall be capable
of making additional starts with a cooling period at standstill between
starts not greater than 45 minutes. Enclosures shall be fabricated of cast
iron or steel, and shall be furnished with corrosion-resistant hardware.
Enclosures shall be weather-protected NEMA Type II. Horizontal motors
shall be furnished with sleeve type bearings. Bearings, bearing brackets,
and end shields shall be split type when available for the frame size and
enclosure furnished. For motors, furnish oil rings; oil reservoirs; sight
glasses located to be readily observable, and marked with the proper oil
level when running and at standstill; and drain and fill piping to a
location where each bearing and reservoir can be flushed, drained, and
refilled. At least one bearing shall be insulated when required to prevent
bearing or shaft damage due to stray shaft currents. Each horizontal motor
shall be mounted on a common baseplate with the driven equipment, or shall
be furnished with separate sole plates and subsole plates to permit removal
of the motor without disturbing the alignment of the driven equipment.
Thermostatically controlled heaters shall be furnished in each bearing oil
reservoir of outdoor motors. Heaters rated 1,200 watts and less shall be
rated 120 volts, single phase; heaters rated above 1,200 watts shall be
rated 240 volts, single phase. One thermocouple type temperature detector
shall be furnished for each sliding type bearing as specified in paragraph
entitled "Slide Bearings." A vibration transducer mounting pad shall be
furnished on the output shaft bearing housing of each motor connected to
equipment specified with a bearing vibration system. Space heaters shall
be furnished on each motor. Space heaters rated 1,200 watts and less shall
be rated 120 volts, single phase; space heaters rated above 1,200 watts
shall be rated 240 volts, single phase. Each motor power lead terminal box
shall be Type II as defined in NEMA C50.41. Each box shall be sized to
enclose connections to synthetic-insulated shielded power cables including
preformed stress cones. Removable molded insulating boots shall be
furnished for factory and field connections in each box. Accessory leads
including temperature detector leads, space heater leads, and current
transformer secondary leads shall be wired to the accessory terminal box.
The motor "A" weighted sound level shall not exceed 84 dBA when measured to
conform to IEEE 85 at a reference distance of one meter.
2.10.3.4
Motor Control Centers
Contractor shall furnish motor control centers with starters and controls
for 3 phase motors rated less than 150 kW 200 hp. Separate motor control
centers shall be provided for each of the spray dry absorber-fabric filter
baghouse units and the lime slurry preparation system. The lime system
motor control center shall be located within the system enclosure. Motor
control centers shall be totally enclosed dead-front type suitable for use
on 480-volt, 3-phase, 4-wire, 60-hertz system. Motor control centers shall
conform to NEMA ICS 6 and UL 845. Motor control centers shall consist of
individual vertical self-supporting sections, nominally 508 mm wide, 508 mm
deep, 2286 mm high 20 inches wide, 20 inches deep, and 90 inches high,
bolted together on floor sills. Sections shall be divided into
compartments for control equipment and arranged for future additions at the
ends. Structures shall be rigid and sufficiently braced to prevent
movement of control centers when inserting or withdrawing removable units.
Compartment doors shall be hinged full length and equipped with quick
captive screws and neoprene gasket on each compartment door. Guide rails
SECTION 23 51 43.00 20
Page 71
shall be provided for alignment of plug-in units. Plug-in units and doors
shall be accurately constructed and aligned to prevent binding. Control
centers shall be arranged for front mounting of equipment and control units
shall be plug-in type with wiring accessible from the front. Plug-in units
shall be draw-out or tilt-out type with provisions for padlocking in the
disconnected position. Disconnecting stabs shall be pressure type of
silverplated high-strength copper alloy. Control center disconnecting
devices shall be provided with external operating handles arranged for
padlocking in the "off" position and the compartment doors shall be
interlocked to permit opening only when the disconnect device is in the
"off" position. Control center enclosure shall be NEMA 1 and wiring shall
be NEMA Class II, Type B. Control center main horizontal buses shall be
rated as required for the connected loads, but not less than 600 amperes,
and vertical buses for each section shall be rated as required for
connected load, but not less than 300 amperes, both at a continuous rating
at 50 degrees C 122 degrees F rise. Buses shall withstand stresses of
short-circuit currents of 42,000 amperes rms. A ground bus shall be
provided at the bottom for the full length of the motor control centers.
Furnish each vertical section with continuously energized space heaters as
required to prevent condensation during construction. Space heaters shall
be applied at one-half rated voltage. Space heaters in a shipping section
shall be wired together and connected to a terminal block that is
accessible before the motor control center is uncrated. Control center
motor starters shall be circuit-breaker combination type and shall be rated
at 460 volts, 3-phase, and shall be the NEMA size classifications required
for motors furnished. Motor starter shall be magnetic, across-the-line,
single speed, two speed or reversing as required. Each starter shall be
provided with a control transformer rated 480/120 volts having a
volt-ampere capacity to suit the control load including control devices,
but not less than 100 VA. A fuse shall be provided in the 120-volt control
circuit for each starter. Control connections shall be as required. Each
starter shall be equipped with three thermal overload relays.
Short-circuit rating of combination starter shall be 42,000 amperes rms
symmetrical. Starters shall be wired to the terminal block for a remote
auxiliary contact to be provided by the Contractor. The auxiliary contact
will be wired in series with the stop push button, selector switch or
control device to open the control circuit to the starter contractor when
the auxiliary contact is opened. Each motor control center shall be
equipped with two NEMA Size 1, two NEMA Size 2, and one NEMA Size C
complete, spare, full-voltage, nonreversing motor starters. Control center
circuit breakers shall be rated 600 volts ac, manually operated, trip free
from the handle, and with a molded case. Breakers shall be 3 pole unless
otherwise specified. Breakers used in combination motor starters shall be
adjustable instantaneous only, coordinated to provide short-circuit
protection for both the motor circuit and the thermal overload relays in
the magnetic starter. Breakers shall contain inverse-time thermal overload
protection and instantaneous magnetic short-circuit protection.
Combination motor starter circuit breakers shall have a symmetrical
interrupting capacity at 480 volts not less than the motor control center
short-circuit ratings. If current-limiting fuses are used to achieve the
specified short-circuit rating, a positive acting anti-single-phase trip
mechanism must be furnished. Each motor control center shall be equipped
with two 100 A, 3-pole, and one 225A, 3-pole, spare feeder circuit
breakers. Include external handle which clearly indicates when breaker is
"on," "off," or "tripped." Handle shall be lockable in the "off"
position. Control centers shall be ambient compensated to 50 degrees C 122
degrees F. Control centers that utilize frame sizes 225 ampere and larger
shall be furnished with interchangeable trip units. Circuit breakers shall
conform to NEMA AB 1 and shall meet the appropriate classification of
SECTION 23 51 43.00 20
Page 72
FS W-C-375.
2.10.3.5
Factory Tests
<TESTPerform factory tests on each motor rated 460 volts and below in
conformance with NEMA MG 1, and IEEE 112 or IEEE 114. Tests shall include:
a.
No-load current and speed tests at normal voltage and frequency,
b.
high potential test, and
c.
standard factory tests.
Perform factory tests on each motor rated above 460 volts in accordance
with NEMA C50.41 and IEEE 112. Tests shall include:
a.
Measurement of winding resistance,
b.
no-load test with readings of current, power, and nominal speed at
rated voltage and frequency,
c.
mechanical vibration test,
d.
direction of rotation versus phase sequence test,
e.
insulation resistance test, and
f.
high-potential test.
2.11
DUCTWORK AND DRAFT EQUIPMENT
Provide self cleaning ductwork for the Flue Gas Cleaning System from the
economizer outlet to the stack inlet as indicated, including fabric filter
baghouse reverse gas ducts, if required, complete with necessary expansion
joints, transitions, structural slide bearings, dampers, turning vanes, and
support steel. Provide 100 mm 4 inch pipe coupling test ports upstream and
downstream of each spray dryer absorber and upstream of each guillotine
system isolation damper. Test ports in horizontal ductwork shall be
located in the side of the ductwork and test ports shall be of sufficient
length to extend 102 mm 4 inches beyond the insulation and lagging to be
provided by the Contractor. Test ports shall be Schedule 40 316 stainless
steel, pipe conforming to ASTM A167 with screw plugs. Coat each plug with
antiseize lubricant suitable for service at the design temperature
extremes. Exact locations and number and arrangement of ports at each
location shall be determined by the Contractor following the model test.
Except for the ductwork between the spray dryer absorber and the fabric
filter baghouse, duct runs in which the Contractor intends to locate test
ports shall be arranged to conform to at least the minimum requirements of
U.S. EPA Regulation 40 CFR 60, Method 1, relative to the spacing between
test port locations and flow disturbances in the upstream and downstream
directions. Final location and arrangement is subject to approval of the
Contracting Officer. Structural design temperature range for ductwork
shall be [_____] to [_____] degrees C degrees F. Long ductwork sections
shall contain hoppers, clean-out doors, and structural support due to dust
drop out. Ductwork and support steel shall be designed such that no loads
will be applied to the ductwork provided by the Contractor at the interface
points. The expansion joints, bolts, nuts, backing bars and gasketing at
interface connections shall be by the Contractor. Carbon steel ductwork,
support steel, access ways and access doors shall be designed as specified
SECTION 23 51 43.00 20
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2.12.7
Level Elements
Level controllers shall be electrode probe type and shall feature remote
electronic enclosure rated NEMA 4 with integral level indicator. Zero and
span adjustments shall be noninteracting. Proportional band adjustment
shall be provided. Electronic output as required. Power input: 115-volt
AC. Prefabricate cable to connect probe to transmitter with quick
disconnect connectors. Probe and electronic circuitry shall be designed to
provide reliable level control unaffected by coating or material buildup on
probe. Liquid level switch elements shall be dry contact (mercury switch
contacts not acceptable), single-pole-dual-throw, rated for at least 120
volt AC, 4 amperes or 125-volt DC, 0.5-amperes, unless noted otherwise.
Switch enclosure shall be NEMA 12 unless noted otherwise. The float
actuated cage shall be external type with temperature and pressure rating
equal to or greater than the design rating of the vessel to which it is
attached. The float and trim materials shall be stainless steel.
Float-type switches shall not be used for slurry tanks.
Differential-pressure type shall be indicating type switch. Electrode
probe types shall be provided with remote NEMA 4 electronic enclosure with
integral level indicator, and noninteracting zero and span adjustments.
Power input: 115-volt AC, single phase 60 hertz. Probe to transmitter
prefabricated cable with quick disconnect connectors. Level indication
shall be unaffected by material buildup on probe.
2.12.8
Flow Elements
Flanged orifice plates shall be 3 mm 1/8 inch thick, 304 stainless steel,
sized for the service. Furnish a calculated calibration curve based upon
design flow conditions plotting flow versus differential pressure.
Insertion flow elements shall be Pitot-tube type using 304 stainless steel
as material. Provide pipe connections. Application shall be for water
only. Provide inline-magnetic type with liner material and thickness to
match the piping. Accuracy shall be plus or minus one percent of rate.
Power supply shall be 110 volt AC, 60 hertz. Furnish prefabricated cable
from primary element to transmitter. Provide integral indication of flow.
Flow switch elements shall be dry contact (mercury switch contacts not
acceptable) single-pole-dual-throw rated for at least 120-volt AC, 4
amperes or 125-volt DC, 0.5-amperes. Switch enclosure shall be NEMA 12,
except as noted. Materials and pressure ratings shall be compatible with
the service. Flow switch shall be paddle, plunger, differential-pressure,
or ultrasonic type. Ultrasonic flow switches shall be provided with one
flow setpoint, unless otherwise noted. Provide individual adjustment of
setpoint and time response delay. Power input: 115-volt AC, single phase,
60 hertz. Provide NEMA 4 enclosure for electronics and encapsulated sensor
probes. Use only when other types are not recommended for the service.
Flow controllers shall include adjustments for set point, proportional
band, rate, reset, and specific gravity. Provide pressure gages indicating
supply and control pressures. Provide cleanout push button for cleaning
restricted feed orifice without dismantling. Design shall utilize
high-temperature diaphragms and gaskets, and shall provide dust-tight case,
and cooling fins.
2.12.9
Density Elements and Transmitters
Shall be nuclear type and shall be accurate within 0.001-SGU maximum.
Signal shall be linearized. Response of measurement system shall provide
adequate response time when tied to mass flow. Power supply shall be
115-volt AC, single phase 60-hertz. Furnish prefabricated cable as
SECTION 23 51 43.00 20
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required from primary element to transmitter.
2.12.10
Fly Ash Level Alarms
**************************************************************************
NOTE: Alarm sequence shall be the following.
Status
Visual
Audible
Normal
Off
Off
Alert
Fast Flash
On
Acknowledge
On
Off
Return to Normal
Slow Flash
Off
Return before Acknowledge
Slow Flash
Off
Acknowledge (Reset)
Off
Off
Test
On
Off
**************************************************************************
Each fabric filter baghouse hopper shall be provided with a fly ash level
alarm utilizing nuclear type detectors. The detectors shall be
single-point gamma source and detection units. The detectors shall be
complete with separately mounted electronic units which shall include a
local high level indicating light and relays for use with annunciation
system specified in paragraph entitled "Annunciators." Relays shall be
rated 10 amperes, 120 volts AC. Switch housings shall be dustproof and
shall be mounted as one easily accessible location. Detector and source
electronics shall be located at the hopper control panel. Detector shall
be explosion proof and have waterjacketing. Alarm shall be able to
withstand vibration and temperatures up to 260 degrees C 500 degrees F.
The source shall have a lockable shutter mechanism operated by an external
handle to totally isolate the beam when in the closed position. Electrical
wiring schematic shall be furnished. Electrical supply shall be 115 volts
AC, single phase, 60 hertz. Alarm level shall be located at the 50 percent
hopper capacity level. Each hopper shall have two sensors; one at the
alarm level and one at the empty level. Level reproducibility shall be
within one inch. Outdoor components shall operate between [_____] degrees C
and 93 degrees C degrees F and 200 degrees F. Source for each hopper level
sensor shall be Cesium 137. Source head shall be designed with a spring
return off system in the event of remote cable actuator failure. Source
shall be interlocked with hopper access doors to prevent entry into hopper
unless source has been secured. Hopper access door key shall only be able
to open one pair of hopper doors.
2.12.10.1
Hopper Level Signals
Hopper level signals based on hopper status indicator system shall report
to a microprocessor through a coaxial cable system. Each hopper shall have
two indicators, one for full and one for empty. A flashing light shall
indicate a wall buildup. Loss of power for any period of time shall not
require a recalibration. Enclosure for microprocessor shall be [NEMA 4]
[12] and shall be located in [_____]. Each group of detector units for a
SECTION 23 51 43.00 20
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minimum wind velocity of [_____] km/s mph. Design for seismic loads in
accordance with Section 22 05 48.00 20 MECHANICAL SOUND VIBRATION AND
SEISMIC CONTROL. The entire structure along with components shall be
designed in accordance with earthquake regulations for structures located
in Zone [_____]. The site periods shall be between 0.8 and 1.2 seconds,
whichever results in the highest lateral force. The term "W" as used in
the calculations for seismic loading shall be interpreted as the normal
operating weight of the unit including dead loads. Platform live loads may
be excluded. The structural components shall be designed for a snow
loading of [_____] kg per square meter pounds per square foot. The
structural components shall be designed for dust loading of 98 kg per
square meter 20 pounds per square foot. The structural components shall be
designed for dust loading where appropriate based on 1600 kg per cubic meter
100 pounds per cubic foot minimum. Use a higher load where applicable.
Walkways, platforms, and stairs shall be designed for live loads of 488 kg
per square meter 100 pounds per square footplus concentrated equipment
loads. Stair live load shall be 610 kg per square meter 125 pounds per
square foot and shall be designed to carry the live load or a moving
concentrated load of 454 kg 1000 pounds, whichever is greater. Roof
purlins shall be spaced so that the metal roof deck span will not exceed
2.13 meters 7 foot. Design for a roof dead load of 98 kg per square meter
20 pounds per square foot and a live load of 148 kg per square meter 30
pounds per square foot.
2.13.1
Girts and Opening Frames
Provide girts for support of metal-wall panels with maximum spacing of 2.13
meters 7 foot center-to-center and supported on the outside face of the
columns. Girts shall have a girt line or outside edge distance of 560 mm 1
foot 10 inches from the supporting column centerline. Lowest girt on spray
dryer absorbers, fabric filter baghouses, and lime slurry preparation
system enclosure to be located abovegrade (Elevation [_____]) with support
at base of wall by Contractor. Provide closed ends or miter-cut girts at
corners. Provide structural subframing for doors and ventilators located
more than [_____] above grade. Contractor will provide doors, door frames,
and ventilators and will also provide necessary structural subframing from
these items up to [_____] above grade.
2.13.2
Slide Bearings
Provide structural slide bearings for spray dryer absorbers, ductwork, and
fabric filter baghouse to ensure correct alignment, prevent equipment
damage, ensure that stresses in the ductwork, fabric filter baghouse duct,
and supports are not excessive, and to allow efficient system operation at
conditions. Provide ductwork and fabric filter baghouse supports, except
at totally laterally restrained points, with structural slide bearings.
Construct slide bearings with slide bars or other methods to prevent
possible accumulation of ash, dirt, and other materials on the bearing
area. Slide bearings shall have fluoroplastic self-lubricating bearing
elements.
2.13.3
Miscellaneous Steel
Handrail shall be 40 mm 1 1/2 inch round black standard weight pipe
conforming to ASTM A53/A53M Type E or S, Grade B, with two horizontal pipe
runs at 584 mm and 1067 mm1 foot 11 inches and 3 feet 6 inches above top of
walking grating. Handrail, accessories, and kickplates shall be hot-dipped
galvanized after fabrication in accordance with ASTM A123/A123M.
Kickplates shall be 6 mm 1/4 inch thick steel plate. Steel floor grating
SECTION 23 51 43.00 20
Page 106
shall be one-piece, resistance-welded steel construction without notching
of bearing or crossbars before welding. Main bars shall be 5 mm 3/16 inch
thick, spaced not more than 30 mm 1 3/16 inches on centers. Serrate main
bars for outdoor use. Crossbars shall be spaced at four inches on centers
and shall be one of the following shapes: hexagon with 8 mm 5/16 inch
diameter of inscribed circle; rectangular 13 by 5 mm 1/2 by 3/16 inch;
square 6 mm 1/4 inch with spiral twist; round 8.33 mm 21/64 inch diameter.
Grating materials shall be of welding quality and conform to the following
standards: (1) Crossbar - ASTM A108 - Grade 1010. (2) Main Bars ASTM A108 - Grade 1015. Grating finish shall be hot-dip galvanized after
fabrication in accordance with ASTM A123/A123M. Stairs shall be open-riser
type with grating treads and grating landings conforming to "Steel Floor
Grating" an with main bars 25 by 5 mm 1 by 3/16 inch(Serrate main bars for
outdoor use). Stair treads and landings shall be hot-dip galvanized after
fabrication in accordance with ASTM A123/A123M. Stairs shall be supported
with carrier plates 65 by 5 mm 2 1/2 by 3/16 inch by tread width tack
welded to all bearing bars and with 5 mm 3/16 inch fillet welds (one side
only) to the front two and the rear bearing bars, or supported with 35 by
22 by 3 mm 1 3/8 by 7/8 by 1/8 inch minimum size angle welded to the front
and rear bearing bar (one side only). Provide subframing so grating span
on landings does not exceed 1067 mm 3 feet 6 inches. Provide nosing on all
treads and at the head of all stairs. Raised pattern floor plate shall be
6 mm 1/4 inch minimum thickness with surface deformation of the four-way
type. Hot-dip galvanize raised pattern floor plate and straighten warped
plate after galvanizing so that warpage does not exceed one inch for every
3 meters 10 feet in any direction.
2.13.4
Fabrication
Shop fabrication and assembly of steel structures shall be done in
conformance with AISC Specifications, Codes, and Standards. Field welding
shall be shielded metal arc or submerged arc. Shop welding shall be
shielded-metal arc, submerged arc, flux-core arc, or gas metal arc. Welding
shall be done in conformance with the requirements of the AWS D1.1/D1.1M
and AISC Specifications. Field welds shall be shown on erection drawings
in conformance to the applicable standards. Shop connections shall be
welded, riveted, or bolted with high-strength bolts at the Contractor's
option and as allowed by the seismic code. Unless restricted by
consideration of clearance or seismic design criteria, field connections
shall be shown as bolted friction type using ASTM A325M ASTM A325 or
ASTM A490M ASTM A490 bolts and shall be designed to conform to AISC
specification for "Structural Joints Using ASTM A325M ASTM A325 or
ASTM A490M ASTM A490Bolts." Form and weld handrails and do not exceed 1.83
meters 6 feet from center-to-center of posts. Grind welds smooth and even
with the surface of the pipe, remove weld splatter. Carefully form
transitions at corners where change of direction or elevation occurs as
required to provide continuous handrail. Clear columns or other vertical
or horizontal projections by at least 80 mm 3 inches. Furnish plates and
additional items as required for fastening to supporting members. Extend
kickplates 100 mm 4 inches above top of grating and install at the edge of
uncovered openings and at the edge of walkways and platforms. Kickplates
shall be constructed to allow water run-off. Shop fabrication shall be as
complete as possible and within standard industry practice. Large pieces
shall be left unassembled only to the extent necessary for shipment.
2.13.4.1
Grating
Fabricate grating main bars vertical within a tolerance of 2.5 mm per 25 mm
0.1 inch per inch of depth with the longitudinal bow before fastening to
SECTION 23 51 43.00 20
Page 107
such that the connections are self-locking. Shafts shall be sized to
deliver the full operator torque to any one blade, without exceeding
one-third of the shaft yield stress when operating at the worst-case design
conditions. Provide dust-tight stuffing boxes sealed with fluoroplastic
packing material to seal the shaft openings. Stuffing boxes shall be
designed such that the packing can be adjusted or removed from the outside
of the duct, without removing or disturbing the bearings or the linkage.
Adjusting nuts, washers, and bolts shall be 316 stainless steel conforming
to UNS S31600 (.03 to .08C) and shall incorporate a self-locking design,
such that vibrations in the damper unit will not cause backing out of the
bolts. Bearings shall be permanently lubricated, self-aligning type.
Bearings shall be mounted outboard of the damper unit and any insulation
and lagging, in such a manner that leaking packing will not cause the
bearing to become contaminated with fly ash. Each bearing and bearing
mount shall be designed to withstand three times the stress transmitted
from the load on the blades plus the operator output torque. Linkage
system shall be located outside of the damper unit. Linkage system shall
be fully adjustable to compensate for thermal expansion of the frame.
Parts with threaded connections for adjustment shall be carbon steel.
Provide lock nuts on the adjustable linkage to positively hold the linkage
after adjustment. Design shall be such that each individual blade can be
adjusted. Clevis arms shall be pinned or bolted to the stub shaft. Arms
shall be keyed to the shaft for easy removal. Clevis arm shall be carbon
steel and linkage pins or bolts shall be 304 stainless steel conforming to
UNS S30400 (.03 to .08C). Pins or bolts shall incorporate a self-locking
design, such that operation or vibration of the unit will not cause
loosening of the connections. Linkage system, including connections, shall
be designed to withstand three times the stress transmitted from the load
on the blades plus the operator output torque. Linkage system shall have
provisions for locking with a heavy-duty padlock in such a manner that the
damper cannot be operated until the padlock is removed. Sealing strips
shall conform to ASTM B443. Strips shall be bolted into place with bolts
and nuts fabricated of the same alloy as the strips. Connection shall be
self-locking to prevent loosening of the connection. Seal strips shall be
of a suitable length to enable easy replacement in the event of damage or
failure. Sealing strips are not required for induced draft fan dampers.
Louver dampers shall be either parallel or opposed blade. Blades shall be
air-foil type, of rigid structural design. Blade skin and through shaft
shall be compatible material for expansion and contraction. Blade shall be
connected to through shaft with self-locking bolts or pins. Louver dampers
except the induced draft fan inlet control dampers and dampers in vertical
ducts shall be designed for staged closing. Operation of the blade shall
be such that blades close, except the bottom blade. When the upper blades
have closed, then the bottom blade will close. Provide two operators on the
linkage system, one to operate the top blades, and one to operate the
bottom blade. Design of the linkage shall be such that the number of
blades operated by each operator may be changed with relative ease. To
prevent ash buildup at bottom of hopper, install purge air system.
2.11.3.3
Poppet Dampers
Poppet dampers shall be vertically operating, with pneumatic operators,
adjustable speed and stroke, shaft packing glands, replaceable seal plates,
and machined steel seating cylinder and guide shaft. The dampers shall be
equipped so they can be mechanically locked in a closed position to protect
service personnel. Poppet damper shafts shall be out of the dirty gas
stream wherever possible. Shafts exposed to the flue gases shall be
provided with shaft seals. Poppet dampers shall be a minimum of 99.5
percent gas tight.
SECTION 23 51 43.00 20
Page 78
2.11.3.4
Guillotine Dampers
Guillotine dampers shall be bottom-entering dampers in paragraph entitled
"Dampers." Guillotine dampers shall have bonnets over the top frame if
required to prevent flue gas leakage to the atmosphere. Bonnet assembly
shall be of carbon steel and shall have easily removable side plates for
inspection of the damper drive assembly. Bonnet shall be designed for
continuous-seal air purge. Guillotine dampers shall have a removable plate
for access to the bottom frame seal. Damper blade shall be fabricated of
plate, and shall be as rigid as necessary to withstand the maximum
differential pressures specified. Provide blade with sealing strips around
the periphery of the blade and on the seating surfaces of the frame. Local
seals on both the upstream and downstream sides of the blade. Sealing
strips, seal strip bolting materials and backing strips shall be as
specified for louver dampers. Blade shall be designed to include
provisions for thermal expansion such that the blade will not bind.
Bearings shall be permanently lubricated, self-aligning type. Design shall
be such that thermal gradients and long periods of time between damper
operation will not cause bearings to bind or seize. Damper drive shall be
designed to lift the damper blade evenly on both sides. Each drive, tie
rod, and bearing, shall be designed to withstand three times the load
caused by the damper blade plus the operator output torque, at worst-case
pressure and flow conditions. Upper frame shall be designed to support the
blade, drive mechanisms, and attachments. Frame shall not sway and cause
binding of the blade when operating at worst-case flow and pressure
conditions. Pressures and flows provided to the damper manufacturers shall
be approved by the Contracting Officer in advance. Damper shall include a
mechanical crank for manual operation.
2.11.4
Mechanical Draft Equipment
Mechanical draft equipment and appurtenances shall have an acceptable
history of satisfactory reliable service in industrial steam plant use for
a period of a least three years at comparable temperature, pressure,
voltage, and design stress levels. Newly developed equipment with less
than three years actual service may be considered from established
manufacturers, only if it has been adequately tested, at an approved lab
meeting AMCA standards, meets the requirements of this Contract, and is
approved by the Contracting Officer. Prior to shipment, the manufacturer
shall thoroughly inspect parts of the equipment furnished to ensure sound
material and first class workmanship. Rivets shall be tight and welds
shall be full thickness and without undercutting. Keys shall fit snugly
and rotors shall be secured firmly to the shafts. Welding on rotors for
fans shall be examined by magnetic particle inspection. Magnetic particle
inspection shall be performed on the root pass and the finished surfaces of
all welds. On full-penetration welds, the backside of the root base shall
be examined by magnetic particle inspection before depositing weld from the
backside. Welds shall be free from undercutting in excess of 0.40 mm 1/64
inch in depth and free of cracks and fissures in excess of 6 mm 1/4 inch in
length. Inspection of the fans for compliance may be made by the
Contracting Officer. Notify the Contracting Officer, in writing, at least
45 days prior to start of assembly and welding of fan rotors so that he may
have a representative present to inspect fan rotors during fabrication, if
desired. This inspection of the fan rotors will include an examination of
the weld grooves preparations on the material being joined in the assembly
of the fan wheels, witnessing the actual welding being performed on the fan
wheels, a visitation to the manufacturer's nondestructive testing facility,
witnessing the nondestructive testing being performed on welds and base
SECTION 23 51 43.00 20
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material of the fan wheel, and verifying that subassemblies are fabricated
properly and in accordance with the manufacturer's drawings and
specifications. Fans shall be designed and constructed to ensure
reliability with a minimum number of scheduled outages for repairs and
maintenance. Fans shall be suitable for continuous operation at full or
part load. The fans and their ducts, flow-regulating devices and dampers
shall be coordinated to give an installation which will be capable of
operation without excessive vibration, fan noise, or air or gas
vibrations. This satisfactory performance shall be maintained throughout
the entire load range of the fans including operation at minimum flow
settings with cold air. Fans over 19 kW 25 hp shall be two-bearing design
with rotor suspended between bearings with no overhung wheels.
2.11.4.1
Fan Housing
Provide split housing so the rotor is accessible and removable for normal
maintenance without disconnecting the housing from the inlet or outlet
ducts or foundation and without moving the motor. Shape the housing for
maximum streamline flow from inlet to outlet. Construct from mild steel
plate. Brace with structural steel welded to the housing and designed for
sufficient strength to prevent warping and excessive vibration under
operating conditions. Provide with gas-tight inspection doors. Provide
with inlet and outlet connections of structural angle flanges for welding
to similar flanges on the ductwork with bolts provided and used for
alignment only, or for connections to similar flanges on the ductwork by
means of gaskets and bolts. Bolts shall be spaced not more than 65 mm 2
1/2 inches apart. Provide with a 50 mm 2 inch drain pipe connection welded
to the lowest point of the fan scroll. Provide nipple and cap. Housing
will be supported from a concrete base. Housing shall be designed so a
minimum distance of 600 mm 24 inches will exist between the bottom of the
housing and the foundation to permit application of insulation and access
to the housing drain connection. Shop paint fan housings in accordance
with the specifications for painting of the ductwork to which they connect.
2.11.4.2
Fan Rotors and Shafts
**************************************************************************
NOTE: Rotors shall be balanced statically and
dynamically so that vibration displacement at the
bearings measured on the shaft at full load and full
speed with a clean rotor will not exceed the
following.
Maximum Vibration
Rotor Speed, rpm
Displacement, mm
Up to 600
0.051
600 to 900
0.038
Above 900
0.025
SECTION 23 51 43.00 20
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Maximum Vibration
Rotor Speed, rpm
Displacement, inches
Up to 600
0.0020
600 to 900
0.0015
Above 900
0.0010
Weight adjustment for balancing shall be by either
the addition or the removal of metal.
**************************************************************************
Fan rotors shall be designed and constructed to keep stresses from rotation
or temperature differential at a safe and conservative level. Fan rotors
shall be designed so the maximum calculated stress at any point on the
rotor, under any normal condition such as continuous operation or starting
acceleration, will not exceed 50 percent of the yield strength of the rotor
material at the maximum operating temperature. Fan rotors shall have
center plates and shroud plates of mild or alloy steel. Tie rods between
plates or blades will not be permitted. Construct so that while the rotor
is turning, the run-out of similar points on the rotor structure will not
deviate from the median path by more than 0.375 percent of the wheel
diameter. Rotors shall be designed and constructed so that the first
critical speed of the rotor is not less than 33 percent above the normal
operating speed for fans operating at temperatures up to 93 degrees C 200
degrees F and not less than 50 percent above the normal operating speed for
fans operating at temperatures of 93 degrees C 200 degrees F and above.
Fan shafts shall be forged and heat-treated steel, accurately machined,
with ground and polished journal and thrust bearing surfaces. Shafts shall
be provided with seals to minimize leakage where the shaft penetrates the
housing.
2.11.4.3
Bearings
Bearings shall be suitable for continuous heavy-duty service and shall be
self-aligning, sleeve-type journal bearings designed with adequate
lubrication for coast down without an external oil supply. Install
bearings in a horizontal split housing or pedestal of structural steel or
cast iron. Pedestals shall allow removal of bearings without removing
rotor and shall be suitable for shimming. Bearings shall be located
external to the inlet boxes. Bearings on double-inlet fans shall be
designed to withstand the thrust unbalance resulting from the shutoff of
one inlet while the other inlet is open. Protect bearings from the weather
on outdoor installations with a suitable rain hood and sun shield as
recommended by the manufacturer. Each bearing shall have bearing
temperature thermocouple as specified in paragraph entitled
"Instrumentation and Controls." Bearing lubrication systems shall be
specifically designed for air cooling except as noted below. Provide
cooling air by inlet box suction. Inlet air filters shall be provided.
Where the bearing surface rubbing speed exceeds 7.62 m/s 18,000
inches/minute bearings designed for water cooling shall be furnished. Each
bearing shall be equipped with at least two machined oiling rings and an
adequately sized integral lube oil reservoir with oil level gage.
Reservoirs shall be equipped with immersion heaters designed to
continuously maintain the lube oil in the bearing at starting temperature
over the range of ambient temperature specified in paragraph entitled
SECTION 23 51 43.00 20
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3.4
3.4.1
FIELD INSPECTIONS AND TESTS
General
Field testing of the equipment provided under this contract shall include
the tests specified herein. Field testing will be performed by the
Contractor and observed by the Contractor's field representatives as
indicated in Section 01 45 00.00 10 01 45 00.00 20 01 45 00.00 40 QUALITY
CONTROL. If the equipment fails to perform as required by this
specification during any of these tests due to any deficiency in the
Contractor's work, the cost of any repairs and any retesting required as a
result of such deficiency shall be borne by the Contractor.
3.4.2
Hydrostatic Tests
After erection, piping systems shall be given a hydrostatic test 50 percent
in excess of the design working pressure in accordance with the ASME BPVC
Boiler and Pressure Vessel Codes (Sections I, II, V, VIII, and IX) and the
applicable portions of ASME B31.1. Hydrostatic tests shall be conducted
before any piping systems are encased by jacketing or insulation.
Contractor shall provide cold water for the tests and suitable disposal
facilities for wastewater after tests are complete. Contracting Officer
has option to provide or not provide cold water or disposal facilities.
Contractor shall furnish necessary equipment and materials required for
testing including pumps, gages, temporary blank-off plates, gaskets,
anchors, and bracing required to conduct tests. Contractor shall furnish
and install an accurate pressure recorder and continuously record the
pressure during the complete hydrostatic test. Contractor will furnish and
install adequate relief valves to limit the maximum pressure that can be
developed during the hydrostatic test to the specified test pressure. Tanks
will by hydrostatically tested with clear water by filling to not less than
150 mm six inches from the tank top. Welds at tank bottom will be tested
using a bubble technique, as specified in ASTM E515.
3.4.3
Smoke Tests
Spray dryer absorber vessels, fabric filter baghouse modules and breeching
will be given a smoke test with smoke bombs producing a larger volume than
available in the FGD system. The purpose of this test is to detect leaks
due to shop and field welding and at expansion joints around seals. Test
will be made by sealing gas inlets, outlets, and other openings. Pressure
will be produced with a special pressure fan or with compressed air.
Testing equipment and materials will be provided by the Contractor. Perform
testing prior to the placement of insulation and lagging. Leaks found
during the test will be repaired and the equipment will be retested until
complete system is acceptable. Conduct tests at a pressure of 1245 Pa 5
inches W.C. Measure pressure with a suitable water manometer.
High-intensity white smoke bombs shall be used to provide the means for
leak detection. Contractor shall provide equipment and materials required
for the tests including fans, compressor, blank-off plates, gaskets, and
smoke bombs. Notify the Contracting Officer 48 hours in advance prior to
conducting any smoke tests. Tests will be witnessed by the Government's
Field Representative.
3.4.4
Acceptance Tests
**************************************************************************
NOTE: Method 17 of 40 CFR 60 may be used as an
alternative to Method 5. Specify that testing shall
SECTION 23 51 43.00 20
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cleaning system with boiler unit in operation at 100 percent of rated
capacity. Power consumption shall be determined through the use of
watt-hour meters provided by the Contractor for the purpose. Watt-hour
meters shall be used at the power supply inputs to the motor control center
for the lime slurry preparation equipment, the motor control center for the
spray absorber-baghouse combination in operation, and the operating induced
draft fan motor. The watt-hour meters used shall be accurate to within 1.0
percent. Coordinate test schedule and operating requirements with the
Contracting Officer and the Government's operators.
3.4.7
Test Failures
In case any of the equipment furnished under this contract fails to operate
as required, or in case of failure to meet any of the provided for in this
contract, the Government shall have the right to operate the equipment
until such defects have been remedied, and guarantees complied with as
specified in paragraph entitled "Quality Assurance," without cost to the
Government. Failure to meet guarantees for which a schedule of
compensatory damages has been specified may be resolved, at the
Government's Option, by deduction of compensatory damages from the final
payment. Removal of rejected equipment shall be scheduled at the
convenience and discretion of the Government. In the event that serious
defects necessitate the rejection of equipment, the Government will have
the right to operate the equipment until such time as new equipment is
provided to replace the rejected equipment.
3.5
PAINTING
Provide field painting of those surfaces of the following equipment not in
contact with the flue gas stream; cyclones, fabric filter baghouse, fans,
dry scrubber, and ductwork. Field painting shall meet the requirements
specified in Section 09 90 00 PAINTS AND COATINGS. Other equipment
provided in this section shall be painted; either field-painted with
systems conforming to the requirements specified in Section 09 90 00 PAINTS
AND COATINGS or painted with factory or shop painting systems conforming to
the requirements specified in Section 23 03 00.00 20 BASIC MECHANICAL
MATERIALS AND METHODS.
3.5.1
Galvanic Corrosion Prevention
To prevent galvanic corrosion, care shall be used to prevent permanent
contact of aluminum casing with copper, copper alloy, tin, lead, nickel
alloy including Monel Metal. Where it is necessary to attach the casing to
carbon steel or low alloy steel, the steel shall first be prime painted
with zinc chromate, and then painted with aluminum paint suitable for
surface temperatures encountered. The use of lead base paint is not
acceptable.
3.6
SCHEDULE
Some metric measurements in this section are based on mathematical
SECTION 23 51 43.00 20
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conversion of inch-pound measurements, and not on metric measurements
commonly agreed on by the manufacturers or other parties. The inch-pound
and metric measurements shown are as follows:
Products
a.
[_____]
Inch-Pound
Metric
[_____]
[_____]
-- End of Section --
SECTION 23 51 43.00 20
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architecture analog controllers or direct-digital control techniques to
emulate analog controllers. Furnish electronic digital control systems to
control and monitor sequential processes. Provide necessary control
program software and hardware. Furnish control drives and control valve
operators required for control of the FGD system including induced draft
fan inlet damper control drives. Furnish control boards for at least the
following areas or functions: FGD system control panelboard in Steam Plant
control room, lime slurry preparation equipment, lime unloading, and at
each spray dryer penthouse. Control panels in each area shall include the
necessary control devices and instruments required to operate and monitor
the equipment specified for control from that panel. Equipment which is
specified to have both local control and control from the main system
panelboard in the control room shall be provided with control mode selector
switches at the main panelboard. Panelboards shall conform to UL 67.
Analog loops shall be controlled from the main system panelboard only. Tag
each field-mounted device and panel-mounted device using the following tag
numbering scheme. Instruments shall be tagged according to contract number
and type of device using standard device abbreviations. Tag numbers shall
be prefixed with the number [_____] to signify this contract. Instruments
furnished in multiples for multiple equipment shall have identical tag
numbers suffixed by the letters A, B, C, etc., to correspond to the
multiple equipment. Tag each device prior to shipment. Device tags shall
be permanently attached (not with string or tape) to the stem or case of
each device. Tags shall be fabricated of solid brass or aluminum with
correct tag number stamped clearly on into the metal. Each tag shall be
inscribed with a unique tag number assigned using the specified scheme.
Submit drawings of mounting locations for devices to be mounted.
2.12.1
System Operation
**************************************************************************
NOTE: Failure Analysis. Provide a complete control
system failure analysis demonstrating and explaining
the effects of various system component failure on
the system. The failure analysis shall specifically
identify the control system features which will be
provided to minimize the effect of component
failures and protect the equipment, especially the
fabric filter bags.
**************************************************************************
Operation and control of the Flue Gas Cleaning System shall be accomplished
by a full-time operator from the steam plant control room. The control
system shall be designed to allow operation of FGD system in either of two
modes; remote manual or semi-automatic. In the remote manual mode the
various dampers, control valves, pumps and associated equipment will be
opened or closed, started or stopped from individual switches or push
buttons located on the main control panel. In the semi-automatic mode the
FGD system components for each boiler will automatically placed in or taken
out of service in the proper sequence when the start or stop push button is
activated. In both modes sufficient interlocks shall be provided to assure
that proper sequencing is followed and to allow equipment to be
automatically tripped when required. The control system shall be designed
to ensure that in the event of a power failure of FGD system equipment
failure, the necessary corrective action to prevent damage to the equipment
will automatically be initiated. Contractor shall provide a complete
system failure analysis. Process variable indicators and alarms required
for proper monitoring of system performance shall be located on the main
control panel. Furnish necessary instrumentation to provide positive
SECTION 23 51 43.00 20
Page 85
indication of operational status of equipment; such as, flow or pressure
switches to verify operation of pumps and limit switches to indicate
position of dampers and valves. Local controls shall be provided for
valves, dampers, and motors. A complete system graphic display shall be
provided.
2.12.1.1
Lime Slurry Preparation
Provide a control panel adjacent to the truck unloading fill pipe
connection. Provide a NEMA 4 enclosure for panel. Panel shall include bin
vent filter fan indicating light, low bin level indicator light, high bin
level indicator light and audible alarm with alarm silencer button. When
truck unloading tube is connected to the fill pipes, a limit switch mounted
on the fill pipe shall be actuated. Limit switch actuation shall activate
bin vent filter exhaust fan. Disconnection of truck pipe shall return
limit switch to normal and operate bag cleaning mechanism for a preset
period of time. Reaching high bin level during truck unloading shall sound
alarm. Level switches for high and low feed bin level shall be provided,
as specified in paragraph entitled "Instrumentation and Controls." Provide
local and remote monitoring of feed bin levels. Provide signal from low
and high bin level indicators as required for input to control of pneumatic
lime conveying system from bulk lime storage silo. Silo, conveying system,
and controls for bulk lime storage will be provided by the Contractor.
Provide space for additional level monitors on FGD system panelboard for
use with bulk storage silo. Primary control of the lime slurry preparation
operation shall be from the local control panels as specified herein. Main
FGD system control panelboard shall interface with local controls as
specified paragraph entitled "Instrumentation and Controls." Once a
feeder/slaker has been selected for operation from the local control panel,
the lime slurry preparation equipment shall function automatically. A low
level signal from the slurry tank level switch shall start water feed, lime
feed, bin vibrator and other equipment as required including slaker
agitator and grit removal equipment. A high-level signal from the slurry
tank shall stop line feed and bin vibrator immediately and provide
continued operation of water feed, slaker agitator and grit removal
equipment for adjustable time periods. Provide control panels at the time
slurry preparation area enclosure preparation area enclosure and shall
include complete controls for equipment in the slurry preparation system.
In addition to selector switches or push buttons for all equipment, the
local controls shall provide full instrumentation to annunciate any
component failures and automatically trip equipment. Local annunciator
shall be provided for component faults including high slaker temperature,
slaker overflow, slaker fail-to-start grit remover zero speed, slurry
agitator zero speed, and low-low slurry tank level. Any local alarm shall
register at the main FGD system panelboard in steam plant. Flushing of the
slurry pumps and piping systems shall be controlled from a panel at the
slurry tank level in the lime system enclosure.
2.12.1.2
Spray Dryer Absorbers
The following paragraphs provide a typical functional description of the
control of sulfur dioxide concentration and flue gas temperature leaving
the spray dryer absorbers. It is recognized that individual differences
between control schemes may exist to the extent that not all of the control
details specified are applicable to a given system. The [proposal] [bid]
shall clearly indicate such differences and shall include a detailed
description of the control system features provided to attain the control
objectives specified in these paragraphs. The degree of sulfur dioxide
control achieved in the spray dryer absorber and fabric filter baghouse is
SECTION 23 51 43.00 20
Page 86
directly related to the rate of lime feed to the atomizer. The lime slurry
feed rate to the atomizer shall be regulated by a control valve which is
modulated by a signal from the analog control system utilizing an input
from an sulfur dioxide analyzer located at the fabric filter baghouse
outlet. The control valve shall fail closed on loss of air, power, or
control signal and the control system shall be provided with sufficient
interlocks so that FGD system upsets cannot result in excessive liquid feed
and subsequent moisture carryover to the fabric filter baghouse. The
control system shall be designed to automatically control the sulfur
dioxide concentration leaving the fabric filter baghouse at a level set by
the operator from an operating station in the control room. Provide
continuous indication of the inlet and outlet sulfur dioxide concentration,
control valve status and slurry feed rate on the main control panelboard.
The temperature of the flue gas leaving the absorber shall be controlled to
an operator-adjustable setpoint by automatic regulation of water feed to
the atomizer. The water feed rate to the atomizer shall be regulated by a
control valve which is modulated by a signal from the analog control system
utilizing an input from a temperature transmitter located at the spray
dryer outlet. The control system shall provide a means of assuring that
the outlet temperature remains above the moisture dewpoint with an adequate
margin of safety as required to prevent condensation at any point
downstream in the FGD system. A control signal will be available to
indicate the initiation and termination of the steam sootblowing cycle. The
temperature control system shall make use of this signal to automatically
compensate for the additional moisture input with the flue gas. The water
control valve shall fail closed on loss of air, power, or control signal.
Absorber inlet and outlet temperature, water control valve status, and
water feed rate shall be indicated at the main control panelboard. Each
atomizer shall be provided with a local control panel mounted in the
penthouse enclosure. Complete local controls, indicating lights and alarms
shall be provided. Controls for the two-fluid nozzle atomizers shall be as
follows: interlocks and automatic trips shall be provided to automatically
stop the atomizer due to low oil pressure, high oil temperature, high motor
temperature or high vibration level. Remote indication of atomizer
operating conditions and alarms shall be provided on the main control
panelboard. Atomizer start switches shall be provided both locally and
remote.
2.12.1.3
Baghouses
Primary control of the fabric filter baghouses shall be from the FGD system
panelboard located in the steam plant control room. Design the control
system for automatic control of each fabric filter baghouse as required to
ensure stable and reliable operation. Monitor status and position of
motors, dampers, valves, etc. at the main control board by a graphic
presentation. Design for automatic or manual start-up and automatic
verification of the operation of each component of the fabric filter
baghouse in sequence as required for proper operation of the system. The
automatic start-up sequence will be manually initiated. Design for
automatic or manual shutdown and automatic verification of the shutdown of
each component of the fabric filter baghouse in sequence as required for
proper shutdown of the system. Design for automatic and safe shutdown of
any malfunctioning part of the system without disrupting boiler operation
capabilities. Any effect on the steam plant due to system control changes
will be avoided or minimized. The cleaning cycle will be initiated by
measurement of pressure drop across total fabric filter baghouse, by timer,
or by manual switch. Initiation mode shall be switch selectable. A manual
selector switch will allow manual operation of the cleaning function for
any module for the purpose of extra cleaning of any module or in the event
SECTION 23 51 43.00 20
Page 87
of automatic sequence failure. Off-line cleaning of pulse-jet fabric
filter baghouse modules (normal) or on-line cleaning shall be available at
the selection of the operator. The automatic timer and manual selector
switch will be interlocked with an isolation switch located at the tube
sheet access doors to ensure isolation of the module for maintenance. The
automatic timer will bypass any module not in service. This bypass will be
accomplished without timing through the cleaning cycle for the module just
bypassed (no dead time). The cleaning timer will allow for adjustment of
the frequency and duration of cleaning cycles to obtain optimum bag
cleaning. The bypass mode selector for each fabric filter baghouse will be
functional for either automatic control and for manual control. The system
shall automatically bypass the fabric filter baghouse as required to
prevent moisture carryover from spray dryer. Monitor status of process and
equipment for abnormal operation, failure, trip, etc. and provide visual
and audible alarms. Alarm indication shall include, but not be limited to,
high temperature drop across the fabric filter baghouse, high-pressure drop
across fabric filter baghouse, cleaning system malfunction, high ash level
(with indication of which hopper is alarming) and low hopper temperature
(with indication of which hopper is alarming).
Graphic display shall include at a minimum the following indicating lights
(color of lens in parentheses):
a.
Inlet damper--OPEN (green).
b.
Inlet damper--CLOSED (red).
c.
Outlet poppet--OPEN (green).
d.
Outlet poppet--CLOSED (red).
e.
Module--ACTIVE (green).
f.
Module--INACTIVE (red).
g.
High ash level (red)*.
h.
High inlet gas temperature (red)*.
i.
Low compressed air pressure (red)*.
j.
High system differential pressure (red)*.
k.
Power--ON (red).
l.
SYSTEM START (green).
m.
SYSTEM STOP (red).
n.
Cleaning mode OFF-LINE selected (white).
o.
Cleaning mode ON-LINE selected (white).
*These items shall activate an audible alarm.
Two position selector switches shall be provided for the following.
a.
Power--ON/OFF.
SECTION 23 51 43.00 20
Page 88
b.
Module--ACTIVE/INACTIVE.
c.
Cleaning mode--OFF-LINE/ON-LINE.
Momentary contact push buttons shall be provided for the following.
a.
System--START (green head).
b.
System--STOP (red head).
c.
Alarm--ACKNOWLEDGE.
Provide auxiliary devices required for the control functions indicated
including the following.
a.
Position indication switches on isolation valves.
b.
Hopper level alarms.
c.
Temperature indicator and thermocouple.
d.
Pressure switch.
e.
Audible alarm.
f.
Differential pressure gage (baghouse module and panel board).
g.
Fan current.
h.
Fan inlet static pressure.
i.
Fan outlet static pressure.
j.
Opacity.
Provide suitable laminated plastic nameplates for devices on panel face.
Temperature controller and differential pressure gage shall be mounted on
face of panel. In addition, provide a two pen, 250 mm 10 inch diameter
circular chart recorder to record inlet gas temperature and pressure drop
across baghouse system for each module. Differential pressure gage for
each module shall be indicating type with diaphragm magnetically coupled to
pointer mechanism.
Units shall include a programmable controller which shall be completely
solid state and shall be preprogrammed to control the following.
a.
Pulse duration (pulse-jet only).
b.
Pulse sequencing (pulse-jet only).
c.
Cleaning cycle time.
d.
Settling time.
e.
Module isolation valve control.
The system shall sense differential pressure between inlet and outlet of
each baghouse. When the differential pressure reaches the setpoint,
controller shall initiate cleaning of all modules. In addition, an
SECTION 23 51 43.00 20
Page 89
overriding timer shall be provided so that the bags can be cleaned on a
preset interval independent of pressure differential. (Pulse interval and
duration), cleaning cycle time, setting time and time for valve operation
shall all be adjustable. Differential pressure setpoint shall also be
adjustable.
2.12.2
Analog Control Systems
Furnish an analog control system complete with transmitters, flow-measuring
elements, control modules, control system cabinets and panelboard, control
operating stations, prefabricated plug-in cables, signal converters,
control drives and accessories as required to allow control of the FGD
system from the central steam plant control room. The control systems and
instruments shall be electronic and be designed for continuous operation.
The control system shall be of the "split architecture" design where
computing and logic modules are mounted in system cabinets. Operating
stations shall be mounted in the panelboard and connected to the system
control module racks, mounted in the system cabinets, using prefabricated
cables.
2.12.2.1
Electronic Control Modules
Analog computing and logic modules shall use proven solid-state electronic
design. Circuits shall be constructed with high-quality, pretested
components making maximum use of integrated circuits. Components shall be
readily available from known suppliers. Analog computing and logic modules
shall be designed for plug-in rack mounting in the system cabinets. Module
pins and mating connectors shall be gold plated on nickel to withstand
chemical attack by ambient atmospheric chemicals. Modules of the same type
shall be interchangeable to facilitate maintenance and trouble-shooting by
substitution. Pretest and age each module before installing in the module
racks. Factory assemble, wire, and test the system using the operating
stations and actual plug-in cables for the system. Provide input and
output test jacks on each module for tests. Controllers and analog
computing circuits shall perform as follows unless specifically noted
otherwise for a particular system or control loop: Provide calibrated,
front-mounted controls on appropriate modules, to adjust proportional,
integral and derivative action. Adjustments shall be possible while
operating in automatic without causing undesirable upsets such as a
proportional step. Prevent reset windup action and design to develop
response to demand without the system first performing internal controller
balancing. Provide means to automatically balance each loop that has a
manual-automatic operating station so that bumpless transfer may be made
from manual to automatic and from automatic to manual without any
intermediate manual balancing. Where both master stations and individual
final control element stations are employed in a loop, the master, as well
as individual stations shall transfer bumplessly and without balancing, and
be tied together, as appropriate. Bumpless transfer is effected if the
output signal to the final control element does not vary more than 2
percent of the full-scale output signal range when transferring from
automatic to manual and from manual to automatic. Provide for all
interlocks and contact inputs and outputs and all digital logic functions
necessary to control or interface the analog circuits throughout the
system. Provide signal monitor modules to track analog signals where
required to produce contact outputs for alarm or interlock with other logic
when the signal exceeds a predetermined level. Signal monitor units shall
be equipped with independently adjustable high and low set points. Provide
suitable isolating devices such as relays or optical couplers to protect
the control system from external outputs or inputs. Provide indicating
SECTION 23 51 43.00 20
Page 90
lights on the modules to show the status of all logic, transfer relays, and
signal monitors. Lights shall be visible without removing or withdrawing
the modules from the racks.
2.12.2.2
Input and Output Signals
Input signals from field transmitters shall be 4-20 mA dc "two-wire."
Provide output signals to panel recorders and indicators. Provide square
root extraction for flow signals outputs to devices furnished. Output
signals shall be 4-20 mA dc. Transmitters required to provide multiple
outputs to recorders, and indicators as well as providing an input to the
control system shall be buffered so that disconnecting, shorting or
grounding of the input at the recorder or indicator shall not cause an
upset or failure in the control system. Output control signals to final
control elements shall be 4-20 mA dc. The final control elements shall be
provided with the proper signal converter.
2.12.2.3
System Electrical Power and Power Supplies
The following power sources will be provided by the Government: Source "A"
120-V ac from station inverter. Source "B" 120-V ac from station service.
The Contractor shall furnish fuses or circuit breakers for each source to
protect against faults or overloads at the system modules. System
computing and logic power, transmitter power, or other power used for
control or indication, used either remotely or internally, shall originate
from within the system. Such power users shall be properly fused or
furnished with circuit breakers to protect power sources and supplies from
overloads or faults. Power sources and power supplies shall be distributed
into functional groups and protected from overloads or faults such that a
power failure in one group does not cause power failure to the remainder of
the control system. The system shall take appropriate control action and
initiate an alarm contact upon partial power failure. Tripout of a circuit
breaker or opening of a fuse due to control equipment failure or wiring
fault in a control loop shall disable the loop in which the failure
occurred and place the final drive in the manual mode and initiate an alarm
contact. Fuses, breakers, and fuse or breaker panels shall be readily
accessible and clearly identified. Provide input filters for noise
suppression, as required. Where internal dc power supply buses are
utilized, furnish two full-capacity power supplies for each bus voltage and
auctioneer their outputs to ensure no control upsets if one supply or its
source fails. Power one supply from source "A" or "B" is distributed
internally to individual circuit cards or individual transmitters or
converters which have separate dc power supplies, provide an automatic
transfer switch to switch to the backup source upon primary source failure.
Furnish manual reset feature and provide an alarm contact on transfer.
Provide circuit isolation and monitoring to permit removal of faulty
supplies during operation.
2.12.2.4
Operating Stations
Operating stations will be remote mounted on the control panelboard in the
central steam plant control room. Furnish operating station with an
individual mounting rack to permit simple and quick removal from the panel.
Wiring to the system cabinets shall be by a prefabricated plug-in cable.
Operating stations shall contain dials, switches, lights, and indicators
necessary to operate the system by either manual or automatic mode.
Stations shall not contain computing or logic elements which are a part of
the control loop except for operator-system interface. Station shall have
the following features, as applicable, depending upon their purpose in the
SECTION 23 51 43.00 20
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control system:
a.
Manual-automatic selector switch or push buttons.
b.
Dedicated indicating meters displaying only one variable, and marked in
appropriate engineering units where applicable. Indicating lights
displaying manual or automatic status of the control loop. Lights
displaying status of the switch are not acceptable.
c.
Set point dials calibrated and marked in appropriate engineering units.
d.
Deviation meter.
e.
Position meter indicating the actual final drive element position over
its full range, and not the loading signal.
f.
Raise and lower control for manual operation.
Manual, set point, or indicator stations which have specified functions
shall have no extraneous or ineffectual indicators, switches, or lights.
The station shall be tailored to its purpose. Tag operating stations with
a unique number, as specified. Provide an engraved nameplate on each
operating station identifying the service such as spray dryer outlet
temperature.
2.12.2.5
Control Drive
Control drives shall be pneumatic type. The term "control drive" refers to
a power actuator which is primarily used for positioning another device
such as a damper, in response to signals from a control system. Select
each control drive size as required to provide adequate capacity for the
existing loads and conditions. Each control drive used for modulating
service shall positively position its controlled device accurately and
without fluctuations with the existing load conditions and at any position.
The time required for full-stroke travel in either direction shall be 15
seconds. Provide speed control to allow adjustment of full-stroke time
from ten seconds to one minute. Provide couplings, adapters, linkages,
clevises, ball joints, drive arms and damper arms required. Furnish
control drives and handwheels, dual-pole-dual-throw limit switches for open
and closed indication, on open-close drives, and 4-20 mA dc position
outputs on modulating drives. Position shall be sensed electronically
without the use of a slide wire. Provide control drives except the induced
draft fan inlet damper drives with current-to-pneumatic positioners to
accept a 4-20 mA dc control signal. The induced draft fan inlet damper
drives shall be furnished with a pneumatic positioner to accept a 3-15 psi
signal from a current-to-pneumatic signal converter furnished by the
Contractor.
2.12.3
Digital Control Systems
Digital controls shall be relay logic, solid-state programmable logic.
Baghouse sequence control shall be wired solid-state logic or solid-state
programmable logic. Digital logic associated with analog process controls
shall be as specified in paragraph entitled "Electronic Control Modules."
Control circuits shall be 120 VAC maximum. Higher voltage power shall not
be brought into a control system cabinet or control panelboard.
SECTION 23 51 43.00 20
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2.12.3.1
Wired Solid-State Logic
Components shall be highest quality industrial grade devices. Logic
elements shall be integrated circuits. Components shall be subjected to a
rigorous quality assurance inspection. Circuit cards shall be burned-in
and tested in the completed system a minimum of 170 hours continuous
operation. Logic elements shall be assembled on circuit cards to perform
specific operational functions. Different types of circuit cards shall be
minimized to reduce stocking of spares and to facilitate maintenance by
card substitution. Logic cards shall be arranged in functional groupings
for individual pumps or sequences. Failure of a single logic circuit or
compartment shall not affect more than one pump or separate functional
sequence. Power supplies shall be as specified for Analog Control Systems.
System electronics shall be buffered and protected from external power
sources by optical couplers or reed relays. Logic shall be documented by
logic diagrams.
2.12.3.2
Solid-State Programmable Logic
Components shall be highest quality industrial grade devices. Components
shall be subjected to a rigorous quality assurance inspection. Circuit
cards shall be burned-in and tested in the completed system a minimum of
170 hours continuous operation. Small systems requiring a minimum of
memory elements may use nonvolatile programmable memory. Larger systems
shall use software programmable memory with nonvolatile memory for program
and executive storage. Logic functions shall be performed by software
engineer. Logic shall be documented by flow charts or word logic, and by
program listings. Memory shall be static. Programming aids shall be
provided to permit easy field reprogramming. Battery power back-up may be
approved by the Contracting Officer. System electronics shall be buffered
and protected from external power sources by optical couplers or reed
relays. Software shall be factory tested and debugged including simulating
inputs and outputs and checking resulting logic sequences.
2.12.4
Flue Gas Cleaning System Panelboard and System Cabinets
Provide one common vertical panelboard and system cabinet sections, as
specified, to control the flue gas cleaning equipment for boilers.
Panelboard dimensions shall be 0.762 m deep by 2.44 m wide by 2.44 m high
30 inches deep by 96 inches wide by 96 inches high. No process fluids or
pneumatic signal lines shall be brought into any panelboard or system
cabinet.
2.12.4.1
Construction
Construct of 3 mm 1/8 inch hot-rolled steel panels reinforced with angles
and channels in the interior to form a single, rigid, freestanding unit in
compliance with NEMA 12. Panelboards shall be completely enclosed
floor-mounted units, except with bottom open. Panelboards shall be
constructed with no bolt heads or fastenings visible from the exterior.
Construct with 6 mm 1/4 inch radius corners. Edges shall be filled and
ground to conform to a 6 mm 1/4 inch radius. Provide interior innerpanels
for mounting auxiliary equipment and terminal blocks, as required. Make
provisions for anchoring to floor or foundation. Provide hinged doors on
the rear of the panelboard with key locks to allow access to equipment.
Provide lifting eyes and shipping pallet on the panelboard to facilitate
moving into the steam plant. Provide ventilation grills, exhaust fans,
ductwork, and filters, as required. Provide cutouts and removable cover
plates for items designated as future. Paint cover plates to match
SECTION 23 51 43.00 20
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panels. Prime and paint panelboard as specified. System cabinets shall
conform to the following requirements: Steel frame and sides, freestanding,
and fully enclosed. Front and rear access doors with key locks to allow
access to racks. Cabinets shall be maintained at positive pressure using a
fan powered by a 120-volt, single-phase motor with a minimum power output of
0.09 kW 1/8 hp. Maintain cabinet pressure at least at 125 Pa 0.5 inch
water gage. Provide ventilation louvers as required. Size ventilation
system to ensure adequate heat dissipation and to maintain continuous
operation without loss of function or cause reduced life. Pressurizing air
shall be filtered with a 98.5 percent minimum efficiency for dust particles
one micron or larger. Control cabinet shall be equipped with a safety key
interlock (and shall be located as indicated). Assemble cabinets in
sections in sizes convenient for handling and moving into the steam plant,
but with lifting eyes and shipping pallet for each separate section.
Design cabinets to allow sections to be installed side-by-side. Provide
side openings at the bottom of the sections as required to permit
interconnection of the sections by prefabricated cables without routing the
cables outside of the cabinets. Provide work light and one 120 VAC, duplex,
3-wire-polarized-grounding type, specification grade, convenience outlet in
each cabinet.
2.12.4.2
Finish
Smooth, fill, and apply one coat of primer and two coats of finish paint to
exterior surfaces. Apply one coat of primer and one coat of white paint to
interior surfaces. Contractor shall furnish finish paint of type and color
specified by the Contracting Officer.
2.12.4.3
Nameplates
Fabricate nameplates from laminated white phenolic plastic with black
engraved letters. Size of nameplates shall be 40 mm high and 150 mm long 1
1/2 inches high and 6 inches long for "Master" nameplates, with 10 mm 3/8
inch letters. Individual device nameplates shall be 20 mm high and 80 mm
long with 3 mm 3/4 inch high and 3 inches long with 1/8 inch broad
letters. Engrave designations as required later by the Contracting
Officer. Nameplates shall be attached by permanent adhesive or screws.
Self-adhesive, embossed plastic label tape is not acceptable. Fabricated
bezels shall be laminated phenolic plastic with beveled edges, brushed
aluminum or as approved by the Contracting Officer.
2.12.4.4
Graphics
**************************************************************************
NOTE: Refer to paragraph entitled "SPRAY DRYER
ABSORBERS."
**************************************************************************
Provide the FGD system panelboard with a graphic subpanel to pictorially
describe the flue gas cleaning system process to the operator. Graphic
shall include pipelines, pumps, fans, equipment, tanks, vessels, valves,
and dampers that are part of the process, with indicating lights and
control switches located adjacent to the corresponding graphic equipment
symbols. The graphic shall include the flue gas flow path for each of the
[_____] spray dryer absorber and fabric filter baghouse systems. The
graphic subpanel shall be provided with switches, indicating lights and
other devices as required to control and display the status of the
equipment. Indications provided shall include at least the operating
status of the equipment. Indications provided shall include at least the
SECTION 23 51 43.00 20
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operating status (running or stopped) of each pump, fan and other driven
equipment and the position (open and closed) of each valve and damper.
Graphic laminated acrylic symbols on a base of solid acrylic sheeting or
panels shall be constructed of laminated phenolic. Acrylic sheeting shall
be supported by the metal panel surface continuously. Laminated phenolic
may be used as a subpanel. Base sheet shall be 6 mm 1/4 inch thick for
phenolic, 5 mm 3/16 inch for acrylic. Color will be selected later from
manufacturer's standard colors. Provide smoothly finished openings
accurately sized for indicating lights, switches, meters, and oversized
openings in panel metal behind acrylic sheeting. Attach base sheet with
mechanical fasteners which allow for expansion and contraction of the base.
Finish the edge between graphic base sheet and panel surfaces with a
brushed stainless-steel trim. Graphic symbols, flow lines, nameplates
shall be:
a.
Material:
b.
Thickness: Equipment symbols, flow arrows, and nameplates (10 mm (0.40
inch; flow lines: 0.51 mm 0.020 inch).
c.
Color: Solid white core with colored satin finish overlay.
will be selected later from manufacturer's standard colors.
d.
Engraving: Engrave through colored overlay to expose solid core. Cut
laminate with beveled edges (except flow lines) to expose solid core on
perimeter of all symbols, nameplates, etc.
e.
Mounting: Attach to front face sheet by means of contact cement that
may be loosened by a solvent that will not damage face sheet or
symbols. Use of double-faced adhesive tape is not acceptable.
2.12.4.5
Laminated acrylic sheeting.
Colors
Wiring
Interconnecting wiring between the system cabinets and panelboard-mounted
operating stations or subpanels and between separate sections of the system
cabinets shall be prefabricated cables with plug-in connectors at both
ends. Cable connectors shall incorporate a mechanical restraint between
the mating halves to assure that each connecting pin-pair maintains
electrical contact and that the connector does not separate due to
mechanical vibration or cable sag. The male connector shall be of a design
which protects the pins from damage during cable pulling and aligns the two
halves accurately during mating. The connector shall be approved by the
Contracting Officer. Prefabricated cables shall be rated 600 volt, 90
degree C conductor temperature, 18-gage minimum size copper conductors,
overall neoprene or polychlorosulphonate jacket, and shielding if required.
Prefabricated cable length between the panelboard and system cabinets shall
be [_____] meters feet. Provide field terminal blocks in the Flue Gas
Cleaning System panelboard or system cabinets as appropriate for analog and
digital connections of remote devices. Transmitters furnished by this
contract will be wired to terminals in the system cabinets and powered by
the Contractor's power supplies. Field terminal blocks shall be grouped
and wired into the system according to the function or site of the input or
output signals to simplify termination of multiconductor field cables.
Wiring shall be insulated switchboard wire rated for 600 volt ac, 60 hertz,
90 degree C conditions. Size shall be No. 14 AWG or larger for 120-volt ac
control and indicating circuits, No. 20 AWG for low voltage (28 volts or
less) devices, and No. 10 AWG or larger for 120-volt ac main power supplies
and tap circuits. Use heavy-duty terminal blocks rated at least 20
amperes, 600 volts with not less than 15 mm 1/2 inch spacing between
SECTION 23 51 43.00 20
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terminals. Terminal blocks for main power supply circuits and control bus
termination shall be rated at least 40 amperes. Terminals shall be
sliding-link type to allow individual circuit isolation for testing without
disconnecting field or cabinet wiring. Terminal shall be designed to
receive ring-tongue cable connectors on the field side. Terminal blocks
for current transformer circuits shall be 2 or 4 point, as required,
short-circuiting type with one shorting screw for each terminal. Identify
each terminal on all blocks by stamping or permanently marking the terminal
designation on the marking strip. Self-adhesive embossed plastic label
tape is not acceptable. Mount terminal blocks vertically in rows on
interpanels within the panelboard and system cabinets with provisions for
cleating external cables entering from the bottom. Location of the
terminal blocks shall be subject to approval by the Contracting Officer.
No terminal blocks shall be mounted at a height less than 300 mm 12 inches.
Provide a quantity of terminals sufficient for both signal and power
circuits required to implement the system plus 10 percent spare for future
modifications. Provide grouping of the following terminals: (1) Analog,
(2) Annunciator, (3) Control. Provide a ground bus running the full length
of the panelboard and system cabinet sections with No. 4-250 MCM lugs for
ground cable connection at each end. The internal copper ground bus shall
be at least 25 by 6 mm 1 by 1/4 inch. Connect internal grounds required to
the ground bus. Furnish one two-tube, 40-watt, 120-volt fluorescent light
fixture with a protective metal grill for the panelboard. Furnish 120-VAC,
duplex, 3-wire polarized-grounding type, specification grade, convenience
outlets in the panelboard. Furnish single-pole and three-pole fuse blocks
with fuses for each set of relaying and metering potential circuits.
Provide 20A molded-case circuit breakers for connections from control buses
to miscellaneous equipment installed in or served from the panelboard or
system cabinet. Provide plug-in strips for connection of 120 VAC supplies
to meters and recording equipment where required.
2.12.4.6
Power Supplies and Switches
Furnish a circuit breaker panelboard in the FGD system panelboard. Furnish
mechanically interlocked, main circuit breakers mounted in the panelboard
for switching or primary and backup power services. Furnish quantity as
required. Furnish molded-case circuit breaker for each tap from the
control bus to serve items requiring separate AC circuits. Provide one AC
alarm relay connected to each AC bus with two sets of contacts to close
after 2-second delay on loss of AC. Provide a 120-volt AC control bus and
a 120-volt utility bus. Provide 24 VAC or VDC power supplies for low
voltage indicating lights, meters, and transmitters, as required. Control
switches shall be heavy-duty oiltight momentary contact, spring return
unless otherwise specified, with normally open and normally closed contacts
of adequate quantity. Switch handle types, colors, and retaining rings
will be as required. Metal nameplates shall be used for position marking,
but plastic nameplates shall be used for identification, as specified,
unless otherwise noted.
2.12.4.7
Lights and Indicators
Indicating light size shall be nominal 15 mm 1/2 inch diameter and rating
shall be 120 volts ac. Lens shall be transparent, color to be indicated
later by the Contracting Officer, unless otherwise specified. Indicators
shall be of the high-accuracy D'Arsenvol type. Provide indicators in
groups, as required, with mounting hardware and frame. Meter movement
shall be suitable for 4-20 mA dc input signal. Scale markings and colors
shall be as required. Scales shall be illuminated.
SECTION 23 51 43.00 20
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2.12.4.8
Counters and Meters
Six-digit pulse counters to interface with 4-20 mA dc input shall be
provided, as required. Meters shall be semi-flush mounting, 70 mm 2.7
inches square. Accuracy shall be rated at plus or minus 2 percent. Meter
movement shall be 0-5 ampere AC, 0-1 milliampere DC signal. Scales shall
be as specified with overload red lines. Pushbuttons shall be heavy-duty
oiltight construction. Contacts shall be momentary, one normally open and
one normally closed, unless otherwise specified. Button type and color
shall be specified later by the Contracting Officer.
2.12.4.9
Recorders
Multipoint printing strip chart size shall be 254 mm 10 inchesnominal
width. Chart speed shall be 50 mm 2 inches per hour, nominal. Printing
period shall be 5 seconds per point or multi-speed using numbered dots or
plus signs with color selected later by the Contracting Officer. Provide
engraved legend plate and rubber legend stamp. Provide a 12 month supply
of charts and ink for each instrument. Recorders shall be designed for 120
volt AC power. Supply one complete set of manufacturer's tools and
accessories. Provide internal fluorescent illumination. Furnish input
circuitry for thermocouple, RTD, voltage and current input signals.
Provide three separately adjustable alarm points with latching relay for
wiring to the annunciator. Miniature pen strip chart size shall be 100 mm
4 inch nominal width. Chart speed shall be 25 mm one inch per hour.
Provide indicating scale for each pen and scale legend markings. Provide a
12 month supply of charts and ink for each instrument miniature pen strip
chart recorder.
2.12.4.10
Annunciators
**************************************************************************
NOTE: Alarm sequence shall be the following.
Status
Visual
Audible
Normal
Off
Off
Alert
Fast Flash
On
Acknowledge
On
Off
Return to Normal
Slow Flash
Off
Return before Acknowledge
Slow Flash
Off
Acknowledge (Reset)
Off
Off
Test
On
Off
**************************************************************************
Annunciator shall consist of remote logic rack and separate lamp box
assemblies for control room applications, and integral logic, terminal
blocks, and lamp box assemblies for local control panels. Mount the remote
logic racks for the system panelboard annunciator in the system cabinets.
Provide prefabricated display cables to connect the remote logic with lamp
SECTION 23 51 43.00 20
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box assemblies mounted in the panelboard. Equipment shall be constructed
of the highest quality solid-state electronics, factory-tested and burned
in. Trouble contact circuitry shall meet IEEE C37.90.1 Surge Withstand
Capability Test. Provide repeat contacts for each window wired to
terminals. Equipment shall be powered from the Government's 120-volt AC
station service source. Arrange power supplies, circuit breakers, and
input terminal blocks in groups to permit servicing single sections of the
annunciator system without disabling the entire system. Alarm windows
shall be full 50 by 80 mm 2 by 3 inch nominal size. Cable connectors to
lamp box assemblies shall be right-angle type to allow rear connection and
cable routing from below. Terminal blocks in equipment cabinets shall be
slide-link type. Provide terminal marking strips. Alarm audibles for the
annunciator systems shall be electronic tone generators with variable pitch
and volume controls.
2.12.5
Temperature Monitor
Temperature monitor shall scan thermocouple inputs, monitor critical
process conditions, and record temperature in degrees C degrees F and point
number upon alarm or operator demand. Scanning shall be continuous;
recording shall be automatic for each alarm detected. Input point number,
process value, and alarm condition shall be printed on a strip recorder.
Front panel controls shall enable the operator to select scanning rate,
continuous scanning, single point or group scanning, and print-on-alarm or
print-on-demand. A digital display shall present point number and value
for visual monitoring of any or all selected points. In addition to
critical process temperatures such as spray dryer and fabric filter
baghouse inlet and outlet temperatures, inputs shall include bearing
thermocouples and motor RTDs (one per motor). Instrument calibration
accuracy shall be one half degree C one degree F, or better, throughout the
temperature range of 18 to 149 degrees C zero to 300 degrees F and one
percent full scale for process variables. Calibration stability shall be
within one half degree C one degree F for six months with no adjustment,
and equivalent value for process variables. Scanning rate of 6 points per
second, continuous shall be used. Print speed shall be 6 lines per
second. Provide five separate high-temperature alarm comparators with dual
field adjustable set points wired for assignment to groups of inputs.
Provide one isolated lock-in type alarm contact for each alarm set point
for wiring to external annunciator, and wired for manual reset from a
remote push button. Monitor output printer shall be numeric strip chart,
nonimpact ribbonless, roll-type with take-up reel. Provide extra supply of
paper for printing at least 10,000 lines. Provide for flush panel mounting
with printer, indicators, and operator's controls accessible from the
front. Alarm set-point modules, input modules, and auxiliary chassis shall
be mounted behind panel or adjacent to operator's controls. Controller
sensing element shall be stainless-steel armored bulb and capillary, 7.62
meter 25 feet in length. Controller shall include the following features:
a.
Reset and rate as specified.
b.
Set point, proportional ban, reset and rate adjustment.
c.
Pressure gages for supply and control pressure.
d.
Indicator for process temperature.
e.
Supply air pressure regulator.
Provide thermowell sized for the bulb in accordance with the thermowell
SECTION 23 51 43.00 20
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specification. Temperature switch elements shall be dry contact (mercury
switch contacts not acceptable) single-pole-dual-throw, rated for at least
120 volt AC, 4 amp or 125 volt DC, 0.5-amp. Switch enclosure shall be NEMA
12. Sensing element shall be stainless-steel armored bulb and capillary,
or direct-mounted bulb, as specified. Provide thermowell sized for the
bulb in accordance with the paragraph entitled "Thermowells." Factory
adjust each switch to the proper setting before shipment to the jobsite.
Indicate the factory setting on the device tag.
2.12.5.1
Thermometers
Thermometers shall be dial type with an adjustable angle suitable for the
service. Provide thermowell sized for each thermometer in accordance with
the thermowell specification. Fluid-filled thermometers (mercury is not
acceptable) shall have a nominal scale diameter of 125 mm 5 inches.
Construction shall be stainless-steel case with molded glass cover,
stainless-steel stem and bulb. Stem shall be straight, length as required
to fit well. Bimetal thermometers shall have a scale diameter of 90 mm 3
1/2 inches. Case shall be hermetic. Case and stem shall be constructed of
stainless steel. Bimetal stem shall be straight and of a length as
required to fit the well.
2.12.5.2
Thermocouples
Pipe thermocouples shall be Type J, iron-constantan element, ungrounded,
for pipeline mounting in a thermowell. Provide protective sheath, screw
terminal head, and the thermowell sized for the service specified. Element
shall be at least 20 gage wire, with 2 hole insulators, 304 stainless-steel
sleeve, silver plug tip, spring loaded. Head shall be universal type with
screwed cover and chain and terminal connector. Provide stainless-steel
nipple as required for head to clear insulation by at least 50 mm 2 inches.
Well shall be sized for each thermocouple in accordance with the thermowell
specification. Duct thermocouples shall have Type J ungrounded element
with 20 AWG iron-constantan wires 2 hole insulators and universal head as
specified for pipe thermocouples. Protecting tube shall be as specified
under thermowells. Bearing thermocouples shall have Type J ungrounded
element with 20 AWG iron-constantan wires and 25 mm one inch insulator
cemented over measuring junction. Element shall be mounted in 5 mm 3/16
inch spun and welded copper tube, sealed at open end. Head shall be as
specified for pipe thermocouples. Surface thermocouples shall have
ungrounded Type K element (chromel-alumel) at least 20 AWG suitably
protected from high temperatures using fiberglass insulating jacket.
2.12.5.3
Resistance Temperature Detectors (RTDs)
Detector shall be three lead resistance sensor with protective sheath and
screw terminal head for pipeline mounting in a thermowell. Accuracy shall
be plus or minus 1/2 degree C 1 degree F or plus or minus 0.5 percent of
reading, whichever is greater. Element material and nominal resistance
shall be 10 ohm copper. Head shall be universal type with screwed cover,
chain, and terminal connector. Provide stainless-steel nipple as required
for head to clear insulation by at least 50 mm 2 inches. Element length
shall be as required for the insertion depth and insulation thickness
specified. Provide thermowell sized for the element in accordance with the
thermowell specification.
2.12.5.4
Thermowells
**************************************************************************
SECTION 23 51 43.00 20
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NOTE: General. Provide thermowell for each
temperature sensing element (thermometer,
thermocouple, remote bulb, etc.) unless otherwise
noted.
Insertion:
Piping:
65 mm minimum, 150 mm 2 1/2 inch minimum,
6 inchmaximum unless otherwise noted.
Ductwork: At least 1/2 duct depth but not over 910
mm 36 inch unless otherwise noted.
Lagging extension neck: As required to keep well
wrench flats clear of insulation.
Protection: Provide cardboard inserts in each well
to prevent internal damage prior to installing
thermometer in installed well.
Pipeline Wells:
Bore:
Straight or tapered bore sized to fit sensor.
Material:
noted.
316 stainless steel unless otherwise
Ratings: Submit pressure vs. temperature and
velocity vs. insertion length ratings for each type
of well furnished. Submit calculations (to verify
that wells are safe for the specified conditions)
for special wells for which ratings are not
available.
Duct Protecting Tubes:
Type
Material (unless otherwise noted)
25 mm Schedule 80 pipe, closed end
Wrought iron
25 mm standard weight pipe, closed end
Type 446 stainless steel
Adapter: Furnish adjustable flange type collar with companion flange to provide
airtight seal on a 50 mm pipe nipple fastened on the duct or casing. The adapter
must completely support the tube; no intermediate supports will be provided.
Type
Material (unless otherwise noted)
1 inch Schedule 80 pipe, closed end
Wrought iron
1 inch standard weight pipe, closed end
Type 446 stainless steel
SECTION 23 51 43.00 20
Page 100
Type
Material (unless otherwise noted)
Adapter: Furnish adjustable flange type collar with companion flange to provide
airtight seal on a 2 inch pipe nipple fastened on the duct or casing. The adapter
must completely support the tube; no intermediate supports will be provided.
**************************************************************************
Provide a well for each temperature sensing element (thermometer,
thermocouple, remote bulb) unless otherwise noted. Include specifications
of insertion length, shipping protection, bore, material, and any necessary
adapters.
2.12.6
Pressure Gages
Gage connections shall be bottom for flush, surface or line mounting.
Furnish scale ranges to produce a reading 60 to 70 percent of full scale
during normal operating conditions. Service legends shall be printed on
the gage face by the manufacturer. Include adjustments for set point and
proportional band of pressure controllers. Provide pressure gages
indicating supply and control pressures. Provide cleanout push button for
cleaning restricted feed orifice without dismantling. Case shall be
dust-tight with air bleed hole. Pressure switch elements shall be dry
contact (mercury switch contacts not acceptable) rated for at least
120-volt AC, 4 amperes or 125-volt DC, 0.5-amperes. Contacts shall be
single-pole-dual-throw, or as specified. Switch enclosure shall be NEMA
12. Sensing element shall be type and material suitable for the service.
Factory adjust each switch to the proper setting before shipment to
jobsite. Indicate the factory setting on the device tag. Provide brass
pulsation dampeners and liquid fill with high viscosity silicon oil for all
gages used for steam, water, air, or liquid service. Diaphragm seal
materials shall be 316 stainless-steel diaphragm and bottom housing with a
carbon steel top housing. Provide tip bleed feature for bourdon tube in
pressure sensing element. Provide pigtail siphons for pressure gages in
steam service. Fabricate siphons from 6 mm 1/4 inch seamless carbon-steel
pipe, ASTM A106/A106M Grade A, Schedule 40.
2.12.6.1
Panel Gages
Panel gages shall be provided with 150 mm 6 inch diameter face. Accuracy
shall be 1/2 of one percent of scale range. Case shall be aluminum or
high-impact polypropylene reinforced with glass fiber; solid front face;
blowout back. Dial shall be white laminated plastic with black markings.
2.12.6.2
Header Gages
Header gage face shall be 113 mm 4 1/2 inch diameter. Accuracy shall be
one percent of scale range. Bourdon tube shall be bronze, brazed.
Movement shall be stainless-steel geared. Case shall be polished
stainless-steel. Dial shall be fabricated of aluminum.
2.12.6.3
Differential Gages
Differential gage accuracy shall be 1/2 percent of scale range. Pressure
unit shall be rupture-proof, stainless-steel bellows. Body shall be 316
stainless steel with 6894 kpa (gage) 1000 psig safe working pressure. Dial
shall be 150 mm 6 inch diameter.
SECTION 23 51 43.00 20
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2.12.7
Level Elements
Level controllers shall be electrode probe type and shall feature remote
electronic enclosure rated NEMA 4 with integral level indicator. Zero and
span adjustments shall be noninteracting. Proportional band adjustment
shall be provided. Electronic output as required. Power input: 115-volt
AC. Prefabricate cable to connect probe to transmitter with quick
disconnect connectors. Probe and electronic circuitry shall be designed to
provide reliable level control unaffected by coating or material buildup on
probe. Liquid level switch elements shall be dry contact (mercury switch
contacts not acceptable), single-pole-dual-throw, rated for at least 120
volt AC, 4 amperes or 125-volt DC, 0.5-amperes, unless noted otherwise.
Switch enclosure shall be NEMA 12 unless noted otherwise. The float
actuated cage shall be external type with temperature and pressure rating
equal to or greater than the design rating of the vessel to which it is
attached. The float and trim materials shall be stainless steel.
Float-type switches shall not be used for slurry tanks.
Differential-pressure type shall be indicating type switch. Electrode
probe types shall be provided with remote NEMA 4 electronic enclosure with
integral level indicator, and noninteracting zero and span adjustments.
Power input: 115-volt AC, single phase 60 hertz. Probe to transmitter
prefabricated cable with quick disconnect connectors. Level indication
shall be unaffected by material buildup on probe.
2.12.8
Flow Elements
Flanged orifice plates shall be 3 mm 1/8 inch thick, 304 stainless steel,
sized for the service. Furnish a calculated calibration curve based upon
design flow conditions plotting flow versus differential pressure.
Insertion flow elements shall be Pitot-tube type using 304 stainless steel
as material. Provide pipe connections. Application shall be for water
only. Provide inline-magnetic type with liner material and thickness to
match the piping. Accuracy shall be plus or minus one percent of rate.
Power supply shall be 110 volt AC, 60 hertz. Furnish prefabricated cable
from primary element to transmitter. Provide integral indication of flow.
Flow switch elements shall be dry contact (mercury switch contacts not
acceptable) single-pole-dual-throw rated for at least 120-volt AC, 4
amperes or 125-volt DC, 0.5-amperes. Switch enclosure shall be NEMA 12,
except as noted. Materials and pressure ratings shall be compatible with
the service. Flow switch shall be paddle, plunger, differential-pressure,
or ultrasonic type. Ultrasonic flow switches shall be provided with one
flow setpoint, unless otherwise noted. Provide individual adjustment of
setpoint and time response delay. Power input: 115-volt AC, single phase,
60 hertz. Provide NEMA 4 enclosure for electronics and encapsulated sensor
probes. Use only when other types are not recommended for the service.
Flow controllers shall include adjustments for set point, proportional
band, rate, reset, and specific gravity. Provide pressure gages indicating
supply and control pressures. Provide cleanout push button for cleaning
restricted feed orifice without dismantling. Design shall utilize
high-temperature diaphragms and gaskets, and shall provide dust-tight case,
and cooling fins.
2.12.9
Density Elements and Transmitters
Shall be nuclear type and shall be accurate within 0.001-SGU maximum.
Signal shall be linearized. Response of measurement system shall provide
adequate response time when tied to mass flow. Power supply shall be
115-volt AC, single phase 60-hertz. Furnish prefabricated cable as
SECTION 23 51 43.00 20
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required from primary element to transmitter.
2.12.10
Fly Ash Level Alarms
**************************************************************************
NOTE: Alarm sequence shall be the following.
Status
Visual
Audible
Normal
Off
Off
Alert
Fast Flash
On
Acknowledge
On
Off
Return to Normal
Slow Flash
Off
Return before Acknowledge
Slow Flash
Off
Acknowledge (Reset)
Off
Off
Test
On
Off
**************************************************************************
Each fabric filter baghouse hopper shall be provided with a fly ash level
alarm utilizing nuclear type detectors. The detectors shall be
single-point gamma source and detection units. The detectors shall be
complete with separately mounted electronic units which shall include a
local high level indicating light and relays for use with annunciation
system specified in paragraph entitled "Annunciators." Relays shall be
rated 10 amperes, 120 volts AC. Switch housings shall be dustproof and
shall be mounted as one easily accessible location. Detector and source
electronics shall be located at the hopper control panel. Detector shall
be explosion proof and have waterjacketing. Alarm shall be able to
withstand vibration and temperatures up to 260 degrees C 500 degrees F.
The source shall have a lockable shutter mechanism operated by an external
handle to totally isolate the beam when in the closed position. Electrical
wiring schematic shall be furnished. Electrical supply shall be 115 volts
AC, single phase, 60 hertz. Alarm level shall be located at the 50 percent
hopper capacity level. Each hopper shall have two sensors; one at the
alarm level and one at the empty level. Level reproducibility shall be
within one inch. Outdoor components shall operate between [_____] degrees C
and 93 degrees C degrees F and 200 degrees F. Source for each hopper level
sensor shall be Cesium 137. Source head shall be designed with a spring
return off system in the event of remote cable actuator failure. Source
shall be interlocked with hopper access doors to prevent entry into hopper
unless source has been secured. Hopper access door key shall only be able
to open one pair of hopper doors.
2.12.10.1
Hopper Level Signals
Hopper level signals based on hopper status indicator system shall report
to a microprocessor through a coaxial cable system. Each hopper shall have
two indicators, one for full and one for empty. A flashing light shall
indicate a wall buildup. Loss of power for any period of time shall not
require a recalibration. Enclosure for microprocessor shall be [NEMA 4]
[12] and shall be located in [_____]. Each group of detector units for a
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single fabric filter baghouse shall be incorporated into the unit alarm
system for its respective baghouse so that a high level in any hopper shall
indicate as part of the unit alarm system.
2.12.11
Transmitters
Each transmitter shall be selected and adjusted for the service and
operating conditions required and shall be designed to operate at the
maximum condition expected. Transmitters shall be electronic, two-wire
type with 4-20 mA current signal output powered by 24-volt DC source unless
specified otherwise. Enclosures shall have NEMA 4 rating as a minimum.
Devices shall be designed to operate continuously under the ambient
conditions specified. Furnish condensing pots for flow and level
transmitters when required by the conditions of the measured fluid. Furnish
seal pots or diaphragm seals where required for the fluid being measured.
Furnish transmitter mounting brackets suitable for either surface or piping
mounting. Furnish any power supply, transformer, rectifier, or other
device required to interface the equipment with the system. Magnetic
flowmeter transmitters (signal converters) shall be compatible with the
primary elements. Ultrasonic level transmitters shall be protected from
process fluid corrosion by resistant coating or material. Temperature
compensation shall be within accuracy requirements. Integral output
indication shall be graduated in engineering units. Accuracy shall be at
least plus or minus 2 percent of measured range. Provide with coaxial
cable from each probe to each transmitter. Provide with recommended
installation hardware for flange mounting. Transmitter shall use doppler
effect to filter out moving fill material during measurement.
2.12.12
Limit Switches
Limit switches shall be provided with DPDT contacts. Limit switches shall
be provided with housing conforming to NEMA 4 requirements.
2.12.13
Gage Glasses
Glass shall be 20 mm 3/4 inch borosilicate type class red line tubular.
Length shall be a maximum of 915 mm 36 inches per section. Use multiple
overlapping sections for more than 915 mm 36 inches length allowing one
inch visible overlap between sections. Gage valves shall be offset with 20
mm 3/4 inch union tank connection. Provide four guard rods with holders.
Drain valve shall be 15 mm 1/2 inch globe-type needle valve.
2.12.14
Solenoid Valves
Valve body shall be brass of 316 stainless-steel as required by the
operating conditions. Coil shall be rated for continuous operation in
ambient temperatures up to 50C. Voltage shall be 120 volts AC, single
phase, 60 hertz. Provide design features as required that include 15 mm
1/2 inch threaded conduit hub, explosion-proof construction, metal-to-metal
seats, and manual operation.
2.12.15
Sulfur Dioxide Analyzers
Analyzers shall have a history of successful application in coal-fired
boiler flue gas analysis. Performance shall be unaffected by high moisture
content and high grain loading. Analyzers shall meet or exceed the
applicable requirements of U.S. EPA Regulation 40 CFR 60, Appendix B.
Provide control units, calibration gas, signal cable, mounting flanges,
accessories, and appurtenances required for integration of the analyzers
SECTION 23 51 43.00 20
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into the process control system.
2.12.16
Factory Tests
Notify Contracting Officer, in writing, 45 days prior to factory tests.
Conduct standard tests required by the applicable codes and standards.The
Contracting Officer's representative may be present as an observer during
functional factory testing to assure correct operation of circuits. Perform
factory control systems tests with control system components and
prefabricated cables connected together, except transmitters and control
drive units. Provide an open loop test of each control system to check for
circuit continuity. Provide a completely closed loop simulation for each
analog control system to verify function and response, and to check
direction of response. Provide a completely closed loop simulation for
each digital control system to verify sequence operation, timing, and
software integrity. Test control boards as follows: Supply control boards
with 115-volt AC, 60 hertz, and operate each control switch and selector
switch in all positions to verify that control circuits operate ash shown
on the schematic diagrams. Simulate remote contacts and switches with
jumpers at the appropriate external terminal blocks to verify proper
circuit operation. Test annunciator systems to verify that annunciator
points operate correctly by jumpering or operating alarm initiating device
or jumpering external terminals for remote alarm inputs.
2.12.17
Nameplates
Provide plastic, engraved nameplates for remote mounted devices. Fabricate
nameplates from laminated white phenolic plastic with black engraved
letters. Size shall be 19 mm high and 80 mm long 3/4 inch high and 3
inches long. Attach nameplates with permanent adhesive or screws.
2.13
STRUCTURAL AND MISCELLANEOUS STEEL
Provide structural and miscellaneous steel required to frame and support
the spray dryer absorbers, fabric filter baghouses, ductwork, lime slurry
preparation system, and component parts and equipment. Provide steel
supports, access platforms, grating walkways and stairs for access to spray
dryer absorbers, fabric filter baghouses, and other equipment, as specified
in paragraph entitled "Access." Structural-steel supports shall be
designed to support equipment from the top of concrete foundations set at
elevation [_____] ( 150 mm 6 inches abovegrade). All concrete foundations,
anchor bolts and grouting will be provided by the Contractor. The
Contractor shall allow 50 mm 2 inches for grout, so that the bottom of the
baseplates provided under this contract shall be at elevation [_____].
Provide steel girts, purlins, braces and framing required for enclosures.
Compliance submittals shall include general arrangement and outline
information, foundation design information, structural fabrication
information, and erection information. Unless otherwise specified, all
structural steel shall conform to ASTM A36/A36M, as designated in the
AISC 360, Part I. High-strength structural steel as listed in AISC may be
used if it conform to the appropriate ASTM specification and subject to
approval of the Contracting Officer. Structural steel includes columns,
beams, trusses, baseplates, girts, secondary bracings, purlins, girders and
hangers of structural steel. Miscellaneous steel includes steel other than
structural steel such as edge plates, handrails, stairs, grating, ladders,
and plate. Structural and miscellaneous steel shall be designed to resist
not less than the minimum loadings. Design, fabrication, and erection of
structural steel shall conform to the AISC 360 Manual of Steel
Construction. Structural components shall be designed for wind loads with a
SECTION 23 51 43.00 20
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minimum wind velocity of [_____] km/s mph. Design for seismic loads in
accordance with Section 22 05 48.00 20 MECHANICAL SOUND VIBRATION AND
SEISMIC CONTROL. The entire structure along with components shall be
designed in accordance with earthquake regulations for structures located
in Zone [_____]. The site periods shall be between 0.8 and 1.2 seconds,
whichever results in the highest lateral force. The term "W" as used in
the calculations for seismic loading shall be interpreted as the normal
operating weight of the unit including dead loads. Platform live loads may
be excluded. The structural components shall be designed for a snow
loading of [_____] kg per square meter pounds per square foot. The
structural components shall be designed for dust loading of 98 kg per
square meter 20 pounds per square foot. The structural components shall be
designed for dust loading where appropriate based on 1600 kg per cubic meter
100 pounds per cubic foot minimum. Use a higher load where applicable.
Walkways, platforms, and stairs shall be designed for live loads of 488 kg
per square meter 100 pounds per square footplus concentrated equipment
loads. Stair live load shall be 610 kg per square meter 125 pounds per
square foot and shall be designed to carry the live load or a moving
concentrated load of 454 kg 1000 pounds, whichever is greater. Roof
purlins shall be spaced so that the metal roof deck span will not exceed
2.13 meters 7 foot. Design for a roof dead load of 98 kg per square meter
20 pounds per square foot and a live load of 148 kg per square meter 30
pounds per square foot.
2.13.1
Girts and Opening Frames
Provide girts for support of metal-wall panels with maximum spacing of 2.13
meters 7 foot center-to-center and supported on the outside face of the
columns. Girts shall have a girt line or outside edge distance of 560 mm 1
foot 10 inches from the supporting column centerline. Lowest girt on spray
dryer absorbers, fabric filter baghouses, and lime slurry preparation
system enclosure to be located abovegrade (Elevation [_____]) with support
at base of wall by Contractor. Provide closed ends or miter-cut girts at
corners. Provide structural subframing for doors and ventilators located
more than [_____] above grade. Contractor will provide doors, door frames,
and ventilators and will also provide necessary structural subframing from
these items up to [_____] above grade.
2.13.2
Slide Bearings
Provide structural slide bearings for spray dryer absorbers, ductwork, and
fabric filter baghouse to ensure correct alignment, prevent equipment
damage, ensure that stresses in the ductwork, fabric filter baghouse duct,
and supports are not excessive, and to allow efficient system operation at
conditions. Provide ductwork and fabric filter baghouse supports, except
at totally laterally restrained points, with structural slide bearings.
Construct slide bearings with slide bars or other methods to prevent
possible accumulation of ash, dirt, and other materials on the bearing
area. Slide bearings shall have fluoroplastic self-lubricating bearing
elements.
2.13.3
Miscellaneous Steel
Handrail shall be 40 mm 1 1/2 inch round black standard weight pipe
conforming to ASTM A53/A53M Type E or S, Grade B, with two horizontal pipe
runs at 584 mm and 1067 mm1 foot 11 inches and 3 feet 6 inches above top of
walking grating. Handrail, accessories, and kickplates shall be hot-dipped
galvanized after fabrication in accordance with ASTM A123/A123M.
Kickplates shall be 6 mm 1/4 inch thick steel plate. Steel floor grating
SECTION 23 51 43.00 20
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shall be one-piece, resistance-welded steel construction without notching
of bearing or crossbars before welding. Main bars shall be 5 mm 3/16 inch
thick, spaced not more than 30 mm 1 3/16 inches on centers. Serrate main
bars for outdoor use. Crossbars shall be spaced at four inches on centers
and shall be one of the following shapes: hexagon with 8 mm 5/16 inch
diameter of inscribed circle; rectangular 13 by 5 mm 1/2 by 3/16 inch;
square 6 mm 1/4 inch with spiral twist; round 8.33 mm 21/64 inch diameter.
Grating materials shall be of welding quality and conform to the following
standards: (1) Crossbar - ASTM A108 - Grade 1010. (2) Main Bars ASTM A108 - Grade 1015. Grating finish shall be hot-dip galvanized after
fabrication in accordance with ASTM A123/A123M. Stairs shall be open-riser
type with grating treads and grating landings conforming to "Steel Floor
Grating" an with main bars 25 by 5 mm 1 by 3/16 inch(Serrate main bars for
outdoor use). Stair treads and landings shall be hot-dip galvanized after
fabrication in accordance with ASTM A123/A123M. Stairs shall be supported
with carrier plates 65 by 5 mm 2 1/2 by 3/16 inch by tread width tack
welded to all bearing bars and with 5 mm 3/16 inch fillet welds (one side
only) to the front two and the rear bearing bars, or supported with 35 by
22 by 3 mm 1 3/8 by 7/8 by 1/8 inch minimum size angle welded to the front
and rear bearing bar (one side only). Provide subframing so grating span
on landings does not exceed 1067 mm 3 feet 6 inches. Provide nosing on all
treads and at the head of all stairs. Raised pattern floor plate shall be
6 mm 1/4 inch minimum thickness with surface deformation of the four-way
type. Hot-dip galvanize raised pattern floor plate and straighten warped
plate after galvanizing so that warpage does not exceed one inch for every
3 meters 10 feet in any direction.
2.13.4
Fabrication
Shop fabrication and assembly of steel structures shall be done in
conformance with AISC Specifications, Codes, and Standards. Field welding
shall be shielded metal arc or submerged arc. Shop welding shall be
shielded-metal arc, submerged arc, flux-core arc, or gas metal arc. Welding
shall be done in conformance with the requirements of the AWS D1.1/D1.1M
and AISC Specifications. Field welds shall be shown on erection drawings
in conformance to the applicable standards. Shop connections shall be
welded, riveted, or bolted with high-strength bolts at the Contractor's
option and as allowed by the seismic code. Unless restricted by
consideration of clearance or seismic design criteria, field connections
shall be shown as bolted friction type using ASTM A325M ASTM A325 or
ASTM A490M ASTM A490 bolts and shall be designed to conform to AISC
specification for "Structural Joints Using ASTM A325M ASTM A325 or
ASTM A490M ASTM A490Bolts." Form and weld handrails and do not exceed 1.83
meters 6 feet from center-to-center of posts. Grind welds smooth and even
with the surface of the pipe, remove weld splatter. Carefully form
transitions at corners where change of direction or elevation occurs as
required to provide continuous handrail. Clear columns or other vertical
or horizontal projections by at least 80 mm 3 inches. Furnish plates and
additional items as required for fastening to supporting members. Extend
kickplates 100 mm 4 inches above top of grating and install at the edge of
uncovered openings and at the edge of walkways and platforms. Kickplates
shall be constructed to allow water run-off. Shop fabrication shall be as
complete as possible and within standard industry practice. Large pieces
shall be left unassembled only to the extent necessary for shipment.
2.13.4.1
Grating
Fabricate grating main bars vertical within a tolerance of 2.5 mm per 25 mm
0.1 inch per inch of depth with the longitudinal bow before fastening to
SECTION 23 51 43.00 20
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supports shall be less than 1/200 of the length and the traverse bow before
fastening to supports shall be less than 10.41 mm in one meter 3/8 inch in
3 feet. Crossbars shall not deviate from a straight line perpendicular to
the main bars by more than 5.21 mm in one meter 3/16 inch in 3 feet.
Crossbars shall match crossbars of adjacent sections to form a continuous
pattern of straight lines. Grating panels shall be cut to size and piece
marked. Panel width and length tolerances shall be plus or minus 6 mm 1/4
inch. Provide openings in grating as required for installation of piping
and equipment furnished under this Contract. Band openings 100 mm 4 inches
and larger with a metal bar same size as main bearing bar. Weld to each
bearing bar with 4.76 mm 3/16 inch fillet weld 19 mm 3/4 inch long. Tack
weld to crossbars. Trim band open end of grating at head of ladder, manway
opening, hinged sections, and grating panels with four crossbars or less.
Grating shall be removable. Fasten raised pattern floor plate in place
with countersunk stainless-steel screw at each corner of each piece or plug
weld where permanent fastening is required. Screws shall be flathead, 6 mm
1/4 inch, national coarse thread stainless steel, and shall be countersunk.
2.13.4.2
Stairs
Construction of stringers of channel sections shall be adequate to carry
the specified design loads without excessive deflection. Construct cross
brace stringers to provide lateral stability where the horizontal run
exceeds 3.66 meters 12 feet. Provide struts and hangers where required to
suit specified live load with minimum size as specified. Bolt tread to
stringers with a minimum of two 9.53 mm 3/8 inch, national coarse thread,
stainless steel bolts.
2.13.5
Access
Provide access walkways across top of ductwork from boiler enclosures to
spray dryer absorbers as indicated. Extend walkways to fabric filter
baghouses as indicated. Stair access and platforms shall be supplied to
fabric filter baghouse hopper accessories. Provide stair access and
walkways for access to the tube sheet level of the fabric filter baghouses
with connecting walkways. Internal and external access walkways, lights,
and platforms shall be provided to access doors, inspection or maintenance
points, and other areas where access is required for operation, inspection,
testing, and maintenance. Walkways and platforms at each level shall be
interconnected by walkways at the same level. Walkways including roof,
shall be connected by stairs. Caged ladders shall be provided at each
level for secondary egress. Provide stair access and platforms to lime
system equipment levels. Access shall be provided for dust valves,
manholes, poke holes, hopper vibrators, conveyors, expansion joints,
dampers, portion of the ductwork subject to dust accumulation, gas sampling
points and all parts of equipment requiring routine maintenance, repair or
replacement. Handholds shall be provided inside and outside directly above
each access door. Access doors, and mechanical and electrical components
shall be accessible from a walkway or platform. Complete layout of access
system shall be subject to approval of the Contracting Officer.Provide
supporting steel, grating, handrails, and kickplates electrical lights and
outlets for walkways, stairs and platforms. Arrangement, design, and
fabrication of access systems shall conform to OSHA regulations. Headroom
shall be 2.13 meters 7 foot clear. Provide adequate allowance for
installation of piping, conduit, electrical outlets, and lighting fixtures.
Design exterior walkways and platforms which will be located above ductwork
or other areas requiring insulation and lagging to allow a minimum of 150 mm
6 inches clearance between lagging and bottom of walkway structural steel
assuming that insulation and lagging will be placed on top of ductwork
SECTION 23 51 43.00 20
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stiffeners. Stairs, walkways, platforms, and ladders and their vertical
support steel shall be located a minimum dimension of 0.91 m 3 foot from
the outside column row centerline of structures for which the Contractor
will be supplying and installing metal wall panel. Walkways width shall be
0.91 m 3 foot, minimum. Include handrail and kickplates around platforms.
Design access stairs, as specified. Access stairs width shall be 0.91 m 3
foot, minimum. Include handrail along both sides, top rail to be 762 to
813 mm 2 foot 6 inches to 2 foot 8 inches above edge of tread. Stairs
shall be open-riser type. Stair treads shall be as specified. Stairs
shall have a minimum of 229 mm 9 inch tread and a maximum of 203 mm 8 inches
rise. Minimum width of ladders shall be 457 mm 1 foot 6 inches. Rung
diameter shall be 19 mm 3/4 inch. Rungs shall be spaced at 300 mm 12 inch
on centers. Side rails shall be a minimum of 9.53 by 63.50 mm 3/8 by 2 1/2
inch. Exterior ladders and cages shall be hot-dip galvanized after
fabrication in conformance with ASTM A123/A123M. Provide gas-tight and
liquid-tight access doors to facilitate entry to parts of the flue gas
cleaning system. Access doors shall be 610 mm 24 inch minimum diameter and
the quick opening type. Access doors shall have ethylene propylene
terpolymer (EPDM) gaskets. Provide access doors with hinges to support
door when open. Provide access doors with external latches and tightening
devices which allow for gasket shrinkage without loss of gas-tight seal.
Provide safety chains on access doors to allow door to be cracked open
slightly before opening completely. Provide a means of padlocking access
doors in the open position. Provide inside and outside handholds directly
above each access door.
2.13.6
2.13.6.1
Personnel Access Requirements
Class 1
Regularly attended areas shall have access operating platforms which are
fully accessible by stairs. No ladder or ships ladders for access will be
permitted. Areas included: Lubricated equipment, bearings, instruments,
valve operators, damper operators, damper linkages and drives, test ports,
instrument connections, and equipment requiring access during operation and
for normal day-by-day inspection and maintenance. Platforms at same
elevation on each side of equipment or building shall have a walkway
connecting the two sides.
2.13.6.2
Class 2
Maintenance access areas such as expansion joints, duct access doors,
safety valves, valve packing, and other areas requiring access every two
years or more, shall have access platforms of adequate size to permit two
people to work, 1.12 meter 12 square feet minimum, with access ladders and
maintenance access walkways for reaching the platforms in accordance with
the following: Maintenance access walkways shall be not less than 610 mm 2
foot in width. Ladders shall be as specified in paragraph entitled
"Access." Headroom shall be 2.13 meters 7 footclear except 2 meters 6 foot
6 inches will be allowed in tight locations. Provide adequate allowance
for installation of Government's piping, conduit, and lighting fixtures.
Provide at least two avenues of escape from safety valves or other
hazardous equipment.
2.13.6.3
Class 3
Maintenance access areas, where access is only required for painting,
reinsulation, or replacement of components which have a service life of 10
years or more, shall be met by providing facilities to enable the erection
SECTION 23 51 43.00 20
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of patent scaffolding, temporary ladders, platforms and safety nets to
safely perform the work involved.
2.13.6.4
Maintenance Access Requirements
Provide rotating machinery and mechanical equipment components weighing in
excess of 91 kg 200 pounds with monorails and eyebolts to permit the
equipment to be removed and lowered to grade in a single lift.
2.13.7
Painting
The steel surfaces must be dry and clean in accordance with the following
requirements. Remove grease, oils, and contaminants as outlined in
SSPC SP 1. Remove weld spatter and grind burrs on cut edges and rough
welds smooth. Blast-clean surfaces after fabrication, in accordance with
SSPC SP 6/NACE No.3 and profile depth from 0.038 to 0.064 mm 1.5 to 2.5 mils.
Apply first coat before any rust bloom forms. Apply one coat, dry film
thickness of 0.076 mm three mils, of any of the organic zinc-rich primers
meeting the requirements of SSPC PS 12.01, with a minimum of 82 percent
zinc in the dry film. Apply primer in accordance with manufacturer's
recommendations. Apply primer to steel surfaces except the areas within 50
mm 2 inches adjacent to field welds and surfaces specified to be hot-dip
galvanized.
PART 3
3.1
EXECUTION
INSPECTION
As equipment is delivered to the jobsite, it shall receive a preliminary
inspection by Contractor Quality Control Representative and the Contracting
Officer. The inspection will be continued during the installation after
installation, and during testing. The right is reserved to inspect
equipment at the plant of the manufacturer, during or after manufacture,
and to require reasonable witness tests before shipments are made.
Government and Contractor Quality Control Representatives shall be allowed
unrestricted access to manufacturing and fabrication facilities. Any
equipment rejected shall be either corrected or replaced before
installation. The Contractor shall provide field representatives for
technical direction of the erection, startup, and testing of the FGD system
by the Contractor and for training of the Government's operating personnel.
3.1.1
Contractor Construction Representatives
The Contractor shall furnish experienced, competent, contractor
construction representatives including travel and living expenses, to
advise and consult the Contractor regarding erection procedures and quality
standards for the equipment furnished. These inspection services shall be
furnished from receipt of materials at the jobsite until the equipment and
material furnished under this contract is ready for operation by the
Government. The contractor construction Representative shall be
responsible for the inventory and inspection of equipment and material
furnished under this contract at delivery to determine if the equipment and
material meets the requirements of the specifications for the Contractor's
purpose of recovering, at the Contractor's option, the cost of new
equipment and materials or the cost of corrections or modifications to the
equipment, and materials from the Contractor's, subcontractors, or
suppliers.
SECTION 23 51 43.00 20
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3.1.2
Contractor Construction Representative Areas of Work
The contractor construction representative shall advise and consult with
the Contractor regarding the proper removal of equipment from rail cars,
trucks, and other means of shipment, and the movement of material to and
from storage facilities. Contractor shall advise Contracting Officer
regarding the need for various classes of storage facilities. The
Contractor shall advise the Contracting Officer regarding the protection of
equipment while in storage. Contractor shall review the status of stored
equipment and advise the Contracting Officer of any condition not in
conformance with the Contractor's storage requirements. Contractor shall
review the storage facilities to ensure the following:
a.
Protection of motors, electrical equipment, and machinery of all kinds
against corrosion, moisture deterioration including temporary wiring of
motors space heaters while in storage, mechanical injury, and
accumulation of dirt or other foreign matter.
b.
Protection of exposed machined surfaces and unpainted iron and steel as
necessary with suitable rust-preventive compounds.
c.
Protection of bearings and similar items with grease packing or oil
lubrication.
d.
Handling and storing of steel plate, breeching sections, dampers,
expansion joints, and similar items, in a manner to prevent deformation.
e.
Blocking equipment and material stored outdoors, at least 6 inches
above the ground and arranging for natural drainage with equipment
drain connection open, but protected.
Contractor Construction Representative shall advise and consult with the
Contractor regarding the erection of structural and miscellaneous steel,
installation, and retightening of valves, welding of piping, installation
of instruments and controls, installation of insulation and lagging,
erection of bracing and scaffolding, grouting, retouching paint surfaces,
protection of equipment from freezing, and alignment of equipment.
3.1.3
Field Service Engineer Representatives
Contractor shall include in his bid the cost of the services of competent,
qualified field service engineers from the manufacturers of purchased
equipment. Field service engineers shall provide consulting and advising
services required for placing equipment into successful operation. Field
service engineers shall be provided for the spray dryer, fabric filter
baghouse, hopper heaters, fly ash level detectors, induced draft fans,
pumps, dampers, control valves, air pollution monitors, FGD system
panelboard, and analog control systems. Field service engineers shall
perform an inspection prior to startup to verify that the unit is installed
in conformance with the manufacturer's recommendations. A written report
of the inspection, performed by the field service engineer, shall be
submitted to the Contracting Officer stating his findings including the
acceptability of the FGD system for field performance tests within 15
calendar days after his inspection. Field service engineer shall be on
call for 30 days after start-up.
SECTION 23 51 43.00 20
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3.2
3.2.1
INSULATION INSTALLATION
General
Insulation shall be applied with interruptions to permit access doors,
inspection doors, flanges, and other special features to be opened or
removed for inspection or maintenance without disturbing the insulation.
Boxouts around code stamping symbols and nameplates shall be provided.
Double thickness insulation shall be installed with the joints of the two
layers staggered. Cracks, voids, and depressions in layers of insulation
shall be filled with suitable insulating cements before application of
another layer of insulation as required to allow for thermal expansion
movements which might cause cracks or tears in the insulation. Insulation
shall be installed between stiffeners or over stiffeners in such a manner
that stiffeners are completely insulated. Additional insulation or casing
spacers shall be installed between stiffeners so that a uniform level
surface is achieved. The intent of this insulating procedure is to prevent
a direct metal path between inside the dry FGD system and ambient air.
Insulation shall be securely wired and laced in place using No. 14 dead
soft type 302 stainless steel wire, conforming to ASTM A580/A580M.
3.2.2
Block and Mineral Fiberboard Insulation Installation
Block and mineral fiberboard insulation shall be held in place with
insulation lugs spaced on not greater than 300 by 450 mm 12 by 18 inch
center. The lugs shall be stud type welded in place. Blocks shall be
reinforced on the exterior face with expanded metal, if necessary, to
prevent sagging or cutting of the insulation by the lacing wire. Block and
mineral fiberboard insulation of the specified thickness shall be securely
wired in place over the entire surface by means of wire threaded through
the lugs both ways, pulled tight with the ends of the wire loops twisted
together with pliers, bent over, and carefully pressed into the surface of
the insulation.
3.2.3
Mineral Fiber Blanket Insulation Installation
Mineral fiber blanket insulation shall be held in place with speed washers
and impaling pins spaced on centers not exceeding 300 mm 12 inches.
Mineral fiber blanket insulation shall be provided with expanded metal
reinforcement on the outer surface and wire mesh or expanded metal on the
inner surface. Sections of the blankets shall be tightly butted and jammed
together, and securely tied for maximum sealing at joints. The blanket
shall be secured at joints to prevent peeling or bulging away from blanket
edges. Care shall be taken in applying speed washers so that the designed
thickness of insulation is not reduced when washers are installed.
3.2.4
Protection From Insulation Materials
Equipment and structures shall be adequately protected from damage from
insulation materials. After completion of the work, equipment and
structures shall be cleaned, repaired, and restored to their original
state. Casings which become corroded, discolored, or otherwise damaged
shall be repaired by replacement of casing or other means acceptable to the
Contracting Officer.
SECTION 23 51 43.00 20
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3.3
3.3.1
CASING INSTALLATION
Structural Steel Grid System
Casing shall be installed on aluminized structural steel grid system of
subgirts designed, furnished, and installed by the Contractor. The
subgirts shall be of sufficient size, gage, and depth to provide adequate
support and a smooth exterior surface and shall be welded to the equipment
and structural support surfaces. Subgirts shall be of sufficient depth to
provide for application of the full thickness of insulation over the
stiffeners, access doors, flanges, ribs, and other surfaces having uneven
contours to provide a smooth finished surface. Subgirts on vertical and
bottom surfaces shall be at a maximum spacing of 1220 mm four feeton
centers. Subgirts on roof surfaces shall be at a maximum spacing of 600 mm
two feet on centers. The walking surfaces shall be such as to transmit an
external 114 kg 250 pound walking load from the casing to the structural
steel grid system without compression of the insulation material.
3.3.2
Access Openings
Access doors and other penetrations through the insulation shall have
insulation fitted closely to the fittings and shall be neatly framed and
flashed to make weathertight and to create a pleasing appearance. Hinged
or lift-off doors designed for convenient opening or removal shall be
provided with nameplates, code stampings, and nonprojecting connections at
all access openings. Access openings shall be pitched for water runoff and
have flashing at door head as shown in SMACNA 1793.
3.3.3
Weatherproofing
Install casing with proper overlap to make the installation weathertight.
The casing shall be carefully fabricated and fitted to ensure a neat
appearance. Provide closures, flashings, and seals. The open ends of
fluted sections shall be provided with tightfitting closure pieces.
Flashing shall be suitably formed and installed so that water cannot enter
and wet the insulation. The flashing shall be designed and installed to
readily drain any water that might enter. Joints or openings in casing
which cannot be effectively sealed from entry of moisture by flashings or
laps shall be weatherproofed by application of an aluminum-pigmented sealer
manufactured for this type of service.
3.3.4
Convection Stops
Furnish and install convection stops on vertical surfaces over 3.70 meters
12 feet tall. The maximum interval between convection stops shall be 3.70
meters 12 feet. The convection stops shall consist of steel channels or Z
girts.
3.3.5
Casing Attachment
Attach aluminum casing to the steel structural members by means of No. 14
stainless steel series 300 self-tapping screws on 300 mm 12 inch centers.
Fasten vertical laps and flashing by means of 10 mm 3/4 inch No. 14
stainless steel series 300 sheet metal screws on 300 mm 12 inch centers.
Exposed screws shall have aluminum or stainless steel backed neoprene
washers preassembled to screws. Installation shall be such that the
insulation is not compressed below nominal thickness.
SECTION 23 51 43.00 20
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3.4
3.4.1
FIELD INSPECTIONS AND TESTS
General
Field testing of the equipment provided under this contract shall include
the tests specified herein. Field testing will be performed by the
Contractor and observed by the Contractor's field representatives as
indicated in Section 01 45 00.00 10 01 45 00.00 20 01 45 00.00 40 QUALITY
CONTROL. If the equipment fails to perform as required by this
specification during any of these tests due to any deficiency in the
Contractor's work, the cost of any repairs and any retesting required as a
result of such deficiency shall be borne by the Contractor.
3.4.2
Hydrostatic Tests
After erection, piping systems shall be given a hydrostatic test 50 percent
in excess of the design working pressure in accordance with the ASME BPVC
Boiler and Pressure Vessel Codes (Sections I, II, V, VIII, and IX) and the
applicable portions of ASME B31.1. Hydrostatic tests shall be conducted
before any piping systems are encased by jacketing or insulation.
Contractor shall provide cold water for the tests and suitable disposal
facilities for wastewater after tests are complete. Contracting Officer
has option to provide or not provide cold water or disposal facilities.
Contractor shall furnish necessary equipment and materials required for
testing including pumps, gages, temporary blank-off plates, gaskets,
anchors, and bracing required to conduct tests. Contractor shall furnish
and install an accurate pressure recorder and continuously record the
pressure during the complete hydrostatic test. Contractor will furnish and
install adequate relief valves to limit the maximum pressure that can be
developed during the hydrostatic test to the specified test pressure. Tanks
will by hydrostatically tested with clear water by filling to not less than
150 mm six inches from the tank top. Welds at tank bottom will be tested
using a bubble technique, as specified in ASTM E515.
3.4.3
Smoke Tests
Spray dryer absorber vessels, fabric filter baghouse modules and breeching
will be given a smoke test with smoke bombs producing a larger volume than
available in the FGD system. The purpose of this test is to detect leaks
due to shop and field welding and at expansion joints around seals. Test
will be made by sealing gas inlets, outlets, and other openings. Pressure
will be produced with a special pressure fan or with compressed air.
Testing equipment and materials will be provided by the Contractor. Perform
testing prior to the placement of insulation and lagging. Leaks found
during the test will be repaired and the equipment will be retested until
complete system is acceptable. Conduct tests at a pressure of 1245 Pa 5
inches W.C. Measure pressure with a suitable water manometer.
High-intensity white smoke bombs shall be used to provide the means for
leak detection. Contractor shall provide equipment and materials required
for the tests including fans, compressor, blank-off plates, gaskets, and
smoke bombs. Notify the Contracting Officer 48 hours in advance prior to
conducting any smoke tests. Tests will be witnessed by the Government's
Field Representative.
3.4.4
Acceptance Tests
**************************************************************************
NOTE: Method 17 of 40 CFR 60 may be used as an
alternative to Method 5. Specify that testing shall
SECTION 23 51 43.00 20
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include sootblowing where applicable in certain
states. If necessary provide for steam venting.
Test with fuel close to design parameters. Operate
boiler close to design parameters.
**************************************************************************
**************************************************************************
NOTE: Since most Navy facilities are not base
loaded determine turn down capabilities of system.
**************************************************************************
After a period of initial operation, a performance test will be conducted
on the [entire steam plant] [dry FGD system]. Conduct tests to determine
if, according to the Contracting Officer, equipment and systems provided
under this contract appear to be operating in a reliable and satisfactory
manner. Tests will be conducted to determine if the equipment is
performing as specified. Conduct final acceptance tests for gas cleaning
performance in accordance with the test procedures outlined in U.S. EPA
regulation 40 CFR 60. Performance testing for the fabric filter baghouses
shall conform to methods 1, 3, 5, 6, 7, and 9. [For the purpose of
determining fabric filter baghouse performance, the term "particulate"
shall not include material collected in the impingers of the Method 5
sampling train.] Performance simultaneously testing for sulfur dioxide
removal efficiency will be based on testing upstream of the spray dryer
sulfur dioxide absorber and downstream of the fabric filter baghouse
utilizing Method 6. Three contiguous one-hour runs shall constitute one
test. Tests shall be conducted on the flue gas cleaning equipment for each
of the units. Conduct tests at both 50 and 100 percent of rated boiler
capacity. The operating temperature limits specified will be maintained
during the acceptance tests. [Sootblowers will [not] be operated during
the performance test for sulfur dioxide removal or fabric filter baghouse
performance]. Perform field performance tests by an independent testing
organization approved by the Contracting Officer. The Contractor shall
give written notice to the Contracting Officer, at least 45 calendar days
before scheduled test date, stating that equipment is being scheduled for
test. Perform a trial run of 30 days minimum before actual test to ensure
that associated systems required for the test are ready. Contractor and
the manufacturer's field service engineer shall witness the test. Tests
shall be performed at design conditions herein specified. Conduct the
efficiency tests after the gas cleaning system has been in continuous
service for at least 45 days.
3.4.5
System Stoichiometry Tests
Contractor shall conduct system stoichometry tests for the flue gas
cleaning systems. Measure system stoichiometry as the ratio of moles of
sorbent entering the spray absorber per mole of sulfur dioxide entering the
spray absorber. Sulfur dioxide entering the spray absorber shall be
determined by Method 6 of 40 CFR 60, Appendix A. Sorbent entering the
spray absorber shall be calculated from the lime slurry feed rate and the
calcium hydroxide content of the lime slurry as determined by ASTM C25.
Conduct separate tests for each spray absorber. Tests shall be performed
at both 50 and 100 percent of rated boiler capacity. Contractor shall
consult with the Contracting Officer and with the Government's operators to
coordinate schedules and operating conditions for the tests.
3.4.6
System Power Consumption Tests
Contractor shall measure the total power consumption of the flue gas
SECTION 23 51 43.00 20
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cleaning system with boiler unit in operation at 100 percent of rated
capacity. Power consumption shall be determined through the use of
watt-hour meters provided by the Contractor for the purpose. Watt-hour
meters shall be used at the power supply inputs to the motor control center
for the lime slurry preparation equipment, the motor control center for the
spray absorber-baghouse combination in operation, and the operating induced
draft fan motor. The watt-hour meters used shall be accurate to within 1.0
percent. Coordinate test schedule and operating requirements with the
Contracting Officer and the Government's operators.
3.4.7
Test Failures
In case any of the equipment furnished under this contract fails to operate
as required, or in case of failure to meet any of the provided for in this
contract, the Government shall have the right to operate the equipment
until such defects have been remedied, and guarantees complied with as
specified in paragraph entitled "Quality Assurance," without cost to the
Government. Failure to meet guarantees for which a schedule of
compensatory damages has been specified may be resolved, at the
Government's Option, by deduction of compensatory damages from the final
payment. Removal of rejected equipment shall be scheduled at the
convenience and discretion of the Government. In the event that serious
defects necessitate the rejection of equipment, the Government will have
the right to operate the equipment until such time as new equipment is
provided to replace the rejected equipment.
3.5
PAINTING
Provide field painting of those surfaces of the following equipment not in
contact with the flue gas stream; cyclones, fabric filter baghouse, fans,
dry scrubber, and ductwork. Field painting shall meet the requirements
specified in Section 09 90 00 PAINTS AND COATINGS. Other equipment
provided in this section shall be painted; either field-painted with
systems conforming to the requirements specified in Section 09 90 00 PAINTS
AND COATINGS or painted with factory or shop painting systems conforming to
the requirements specified in Section 23 03 00.00 20 BASIC MECHANICAL
MATERIALS AND METHODS.
3.5.1
Galvanic Corrosion Prevention
To prevent galvanic corrosion, care shall be used to prevent permanent
contact of aluminum casing with copper, copper alloy, tin, lead, nickel
alloy including Monel Metal. Where it is necessary to attach the casing to
carbon steel or low alloy steel, the steel shall first be prime painted
with zinc chromate, and then painted with aluminum paint suitable for
surface temperatures encountered. The use of lead base paint is not
acceptable.
3.6
SCHEDULE
Some metric measurements in this section are based on mathematical
SECTION 23 51 43.00 20
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conversion of inch-pound measurements, and not on metric measurements
commonly agreed on by the manufacturers or other parties. The inch-pound
and metric measurements shown are as follows:
Products
a.
[_____]
Inch-Pound
Metric
[_____]
[_____]
-- End of Section --
SECTION 23 51 43.00 20
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