Reports and Software on Utility and Large Boiler NOx Control Technologies.
“An
essential reference for anyone living with SCR systems.”
Andover
Technology Partners has developed:
Selective
Catalytic Reduction Technology -
Operating
Principles
Operating
Guidelines
Troubleshooting Guide
It is intended to be a
useful reference document for power plant managers, engineers, and operators,
especially those operating SCR systems on coal-fired boilers. It ties together experience on SCR
technology, especially on US coals, and provides advice on lessons that have
been learned from operators throughout the US, abroad, and advice from SCR
technology and catalyst suppliers. The
report also comes with a worksheet that is useful for performing calculations
and budget projections.
The price for a single copy of the SCR Report when purchased
individually is $2,750 plus shipping/handling.
Discounts apply for multiple orders or for orders combined with purchase
of the CAT MANAGER. Contact us for pricing on Enterprise Licenses (may be installed on
a server) or Multiple-User Licenses. Go
to this link (Purchase SCR Report) for
information on how to purchase a user’s license for the document and the
worksheets.
Andover Technology Partners
will also release a document on Selective Non Catalytic Reduction (SNCR)
technology in the coming weeks.
Read further for the Table
of Contents for the SCR report.
Selective Catalytic Reduction Technology
Operating Principles
Operating Guidelines
Troubleshooting Guide
Andover Technology Partners has written a
document to assist engineering managers and operators more effectively manage
their SCR plants. It includes over
sixty figures, including color photos of equipment and service/maintenance
activities. The Table of Contents, List
of Figures and List of Tables is shown.
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Part 1 Selective Catalytic Reduction for NOx Control of Large Boilers 1.1
Introduction 1.2 Post Combustion NOx Control Technologies for Boilers – General 1.3 Selective Catalytic
Reduction – Principles of Operation and General Description of Hardware 1.3.1 SCR Process Chemistry 1.3.2 SCR
System Description 1.3.3 SCR
Hardware Components 1.4 Reagent
Storage and Handling 1.4.1
Anhydrous Ammonia Chemical Specification 1.4.2 Aqueous Ammonia Chemical Specification 1.4.3 Urea Chemical Specification 1.5
Effects of Ammonia and Gas Distribution on Performance 1.5.1 Ammonia and Flue Gas
Distribution Calculating Coefficient of Variation 1.5.2 Ammonia Injection Methods AIGs and Associated Ammonia Distribution Hardware Nozzle Plugging Static Mixers combined with AIGs Adjusting the Ammonia Distribution 1.5.3 Controlling and Preserving the Flowfield Through the SCR Reactor
and Ductwork Turning Vanes, Dummy Catalyst, and General Ductwork Cleaning Dust Off Line On-Line Dust Cleaning Popcorn Slag Dampers Damper Failures
Expansion joints 1.6 Catalyst 1.6.1 Typical Catalyst Composition Selecting a Catalyst Experience, Poison Resistance and Coal Quality (General) Pressure Drop, Price, Lifetime and Other factors (General) 1.6.2
Catalyst Management
Regeneration of Catalyst Evaluating Catalyst Management Strategies Taking
Samples for Monitoring the Catalyst Material
Adding
and Replacing Catalyst Installing a New Layer of Catalyst Removing
and Replacing Installed catalyst- 1.6.3
Catalyst Poisoning/Deactivation Ash – Short-Term Deactivation Long-Term Catalyst Deactivation Mechanisms Calcium Sulfate Formation Arsenic Poisoning The problem with US Coals U.S. Experience with Arsenic Deactivation Arsenic Measurement in Coal Options For Units Experiencing Arsenic Deactivation Implications
for Facilities Burning East Bit. Coal Alkaline Materials Sulfur Effects and Considerations Additive Injection Measuring SO3 |
1.7Controls and Instrumentation Purpose of the Control
System NOx Analyzers 1.8 Ammonia Slip 1.8.1 Deposition of ammonia salts Managing Air Preheater Pressure Drop Buildup Air Preheater Designs for
Lower Depositon 1.8.2 Ammonium Chloride Plume 1.8.3
Measuring Ammonia Slip
Wet Chemical Method Monitoring Ammonia in Fly
Ash Continuous analyzer methods 1.9 Start
Up, Shut Down, and Maintenance Schedules
1.9.1
Start Up SCR
Reactor Heat Up
Pressure
and Flow Transients
Admitting Ammonia
1.9.2 Shut Down of the SCR Lay Up of the Catalyst Reactor 1.9.3
Maintenance Schedules Maintenance
of the SCR System Part 2: Troubleshooting Guide 2.1 Problems That Can Cause High Ammonia Slip 2.1.1 Symptoms High ammonia slip measurement Imbalanced Ammonia Distribution Reactor flow imbalances Catalyst deactivation Ammonia Flowrate Control Bypass Damper Leakby
Temperature Burner Problems 2.2 Causes
of Poor NOx Reduction 2.2.1 Symptoms Bypass Leakage Controls Reagent Other Problems 2.3 SO3-related problems Plume Corrosion or Pluggage of Air Preheaters 2.4 Pressure Drop Problems High pressure drop across the SCR reactor Low pressure drop across the SCR reactor High pressure drop across the air preheater High pressure drop across AIG Part 3.
SCR Analysis Worksheet Inputs Outputs
Input Data Table Input Data Table (con’t) Outputs – Reactor View Outputs – Process Analysis Outputs – Catalyst Addition/Replacement (Chart) Outputs – Cash Flow Analysis Outputs – First Year Costs (Before Tax Basis) Outputs – Before Tax Operating Cash Flows of SCR
(Chart) |
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Figure 1. Temperature window of
SCR reaction Figure 2. Reduction in
catalyst activity and ammonia on fly ash Figure 3. Gas path for coal-fired boiler with High-Dust SCR, ESP and FGD . Figure 4. SCR installation at PP&L Montour #2
Figure 5. An example of an aqueous ammonia storage and vaporization systemFigure 6. AOD™ urea to ammonia
conversion system Figure 7. An example of a U2A
system Figure 8. Increased catalyst
volume requirement due to maldistribution of ammonia, gas flow and
temperature Figure 9. Predicted NOx
Reduction versus Velocity, Temperature, and Mole Ratio Coefficient of
Variation Figure 10. The use of guide
vanes and a mixing system on predicted face velocity distribution at the
first catalyst layer Figure 11. Predicted NOx
Reduction versus Velocity, Temperature, and Mole Ratio Coefficient of
Variation Figure 12 Schematic of SCR
system showing static mixer, turning vanes, ammonia injection grid (AIG), and
flow straightener for gas flow control Figure 13. An Ammonia Injection
Grid (AIG) with upstream and downstream turbulence generators Figure 14. Dilution Air,
Ammonia Control and Distribution Manifolds for Control of Ammonia among AIG
nozzles Figure 15. AIG with various
controlled zones for spatial control of ammonia Figure 16. AIG with preheating to avoid ammonium
bisulfate formation on nozzle tips Figure 17. Babcock Borsig Delta
Wing™ Ammonia Distribution Figure 18. Delta Wing™ and
ammonia injection for 630 MW boiler Figure 19. Photo of Delta Wing™
assembly being put into place on a utility boiler Figure 20. SCR Reactor with 7 x
3 zone AIG Figure 21a. AIG Control Zones
for a 7x3 zone AIG Figure 21b. SCR exit
measurement points and corresponding AIG control zones with two measurement
points per zone Figure 22. Unoptimized and
Optimized Flow with Turning Vanes and Flow Straightener Figure 23. Dust deposition and
erosion of catalyst downstream of a turn with unoptimized flow Figure 24. Dust deposition and
catalyst erosion resulting from flow disturbances Figure 25. Deposits on
unoptimized guide vane Figure 26. Dust deposition in
honeycomb flow straightener Figure 27. Dust deposits on honeycomb
flow straightener Figure 28. Severely eroded
honeycomb catalyst Figure 29. Unoptimized Reactor,
showing heavy deposits Figure 30. Optimized Reactor,
showing light deposits Figure 31. A Rake-Style Soot
Blower used for catalyst cleaning Figure 32. Estimated ammonia
slip if injected ammonia leaks by SCR reactor through bypass and ammonia is
increased to compensate for leakby Figure 33. Estimated effect of
SCR reactor leakby on NOx and ammonia slip if ammonia injection is not
increased to compensate for leakby Figure 34. Effect of pressure
and gravity on large louver dampers that may cause distortion, leakage, and
possible mechanical failure due to flexing and stresses |
Figure 35. Plate and Honeycomb Catalyst
Figure 36. A catalyst module containing steel plate catalyst Figure 37. A catalyst module containing ceramic honeycomb catalyst Figure
38. Installation of Catalyst Modules,
showing Baffle Plates
Figure 39. Catalyst reactor
sized for up to three levels with two layers per level Figure 40a. Catalyst activity vs operating time for SCR of Fig. 13
using a catalyst management plan that only replaces catalyst Figure 40b. Catalyst activity
vs operating time for SCR of Fig. 13 using a catalyst management plan that
initially adds catalyst and then replaces catalyst Figure 41. SCR Reactor being evaluated in Figures 42
a through 42 h. Figures 42 a through h.
Analysis of different catalyst management scenarios for an SCR reactor Figure 43. Extracting Catalyst Plates from an
Element Figure 44. Structural Steel and Sealing Strips for
Catalyst Module Figure
45. Reactor catalyst level top view Figure 46. Lowering the
catalyst module from the temporary hoist on the hydraulic trolley. Figure 47.
Pushing the catalyst module to the final position Figure 48.
Plate catalyst modules on support beams in a top-supported reactor. Figure 49. Final installation
of baffle plates between modules and reactor wall Figure 50. Lambda for Stable
versus Increasing Deactivation Rates Figure 51. k/ko for Stable
versus Increasing Deactivation Rates Figure 52. Calcium Sulfate
Formation in Catalyst Microstructure Figure 53. Deactivation of a honeycomb catalyst by gaseous arsenic Figure 54. Arsenic in Ash versus CaO in Ash for a variety of US Coals Figure 55. The fate of Arsenic
in a Coal Fired Boiler Figure 56. Concentrating
Mechanism in Wet Bottom Boiler with Fly Ash Reinjection Figure 57. Effect of limestone
addition on gaseous arsenic level Figure 58. Effect of limestone
addition on gaseous arsenic level on three different boilers with fly ash
reinjection Figure 59. Estimated Gaseous
Arsenic Concentration Based on OUC Stanton design coal and combustion air
flows Figure 60. Effect of Catalyst
V2O5 content on SOx conversion and NOx reduction activity Figure 61. Example of Control
System, showing monitored parameters and Feed Forward and Feed Back Control Figure 62. SCR Plant and
Component Design Instrumentation Flanges Figure 63. Gas and APH
Temperatures Figure 64. Ammonium Sulfate
(AS) and Ammonium BiSulfate Formation (ABS) Temperatures Figure 65
Ammonium Bisulfate Depostion in a Lungstrom Air Preheater Figure 66. Logan Station APH
Gas-Side Pressure Drop Trend Figure 67. Notched Fixed and
Double Undulated Air Preheater Elements Figure 68. Recommended Minimum
Temperatures/Maximum Humidity for Layup of Catalyst |
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Table
1. Product
Gases of U2A™ Process Table
2. Coefficient of Variation
Calculation for a 3x5 array of points Table
3. Mechanisms
for Catalyst Deactivation by Arsenic and Methods to Mitigate Deactivation Table
4. Coal
Arsenic Concentration Measurements On As Delivered Coal For OUC Stanton #2 for
sample taken October 13, 1998 |
Table
5. Measured
CaO in As-Delivered Coal Ash Table
6 Arsenic Measurement In
Coal - Recommended Methods Table
7. Technologies for
Continuous Measurement From Ammonia Table
8a Inspection Procedures for
the SCR System Table
8b Inspection Procedures for
the SCR System Table
8c Inspection Procedures for
the SCRSystem |
