US4473536A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Catalytic pollution control system for gas turbine exhaust
Assignee: General Electric Co
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Filing: 1982-12-27
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Granted: 1984-09-25
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Expires: 2002-12-27
Abstract
Abstract A steam and gas turbine (STAG) plant employs a catalyst in a heat recovery steam generator to react injected ammonia with NO x from the combustor of the gas turbine to reduce atmospheric emission of NO x from the system. Rapid control of ammonia injection is achieved using a prediction of the NO x being generated in dependence upon the operating conditions of the combustor. A trimming signal from a measurement of NO x being emitted from the heat recovery steam generator downstream of the catalyst is employed to complete the NO x control loop.
Inventors
- 👤 William G. Carberg
- 👤 George L. Touchton, III
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:56
CPC Classifications
F; F02; F02C; F02C3/00; F02C3/20; F02C3/30; B; B01; B01D; B01D53/00; B01D53/34; B01D53/74; B01D53/86; B01D53/8621; B01D53/8625; B01D53/8696; Y; Y02; Y02A; Y02A50/00; Y02A50/20; Y02E; Y02E20/00; Y02E20/16; Y10; Y10T; Y10T436/00; Y10T436/17; Y10T436/177692; Y10T436/178459; Y10T436/179228
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
145 words
Apparatus for controlling admission of ammonia into an exhaust gas stream from a combustion process upstream of a catalyst for reacting with NO x in the catalyst, comprising: means for predicting a predicted amount of NO x produced by said combustion process: means for injecting said ammonia into said exhaust gas stream at a rate effective to react in said catalyst with said predicted amount of NO x to produce a level of NO x downstream of said catalyst equal to a NO x setpoint; means for measuring an amount of NO x downstream of said catalyst to produce a measured NO x signal; means for comparing said measured NO x signal with said setpoint to produce a NO x error signal; and means for correcting said rate in dependence on said error to adjust said NO x downstream of said catalyst toward said setpoint.
Claim 2
Dependent Claim
145 words
Apparatus for controlling admission of ammonia into an exhaust gas stream from a combustion process upstream of a catalyst for reacting with NO x in the catalyst, comprising: means for predicting a predicted amount of NO x produced by said combustion process: means for injecting said ammonia into said exhaust gas stream at a rate effective to react in said catalyst with said predicted amount of NO x to produce a level of NO x downstream of said catalyst equal to a NO x setpoint; means for measuring an amount of NO x downstream of said catalyst to produce a measured NO x signal; means for comparing said measured NO x signal with said setpoint to produce a NO x error signal; and means for correcting said rate in dependence on said error to adjust said NO x downstream of said catalyst toward said setpoint.
Claim 3
Dependent Claim
22 words
Apparatus according to claim 1, further comprising means for compensating said means for controlling in dependence on a temperature of said catalyst.
Claim 4
Dependent Claim
25 words
Apparatus according to claim 1, wherein said means for predicting employs at least a pressure, temperature, air flow and fuel rate to said combustion process.
Claim 5
Dependent Claim
47 words
Apparatus according to claim 1, further comprising means for injecting steam into said combustion process in an amount effective to reduce NO x emission and said means for predicting includes means for correcting said predicted amount of NO x in dependence on the amount of injected steam.
Claim 6
Dependent Claim
20 words
Apparatus according to claim 1, wherein said setpoint includes a preponderance of NO x over ammonia downstream of said catalyst.
Claim 7
Dependent Claim
24 words
Apparatus according to claim 1, wherein said setpoint includes a mole ratio of ammonia to NO x of from about 0.95 to about 1.0.
Claim 8
Dependent Claim
225 words
Apparatus for controlling NO x emissions in a combined cycle plant of the type having a gas turbine producing a heated exhaust and a heat recovery steam generator through which said heated exhaust is passed for generation of steam therein, comprising: a catalyst in said heat recovery steam generator disposed for the passage of said exhaust therethrough; said catalyst being of the type which is effective to react NO x and ammonia to produce nitrogen and water for reduction of NO x in an effluent of said heat recovery steam generator; means for generating a predicted NO x signal based on at least a pressure, a temperature, an air flow and a fuel flow in said gas turbine; an ammonia control system responsive to said predicted NO x signal for injecting an amount of ammonia into said heated exhaust to react with said NO x to reduce said NO x downstream of said catalyst to a NO x setpoint; means for producing a measured NO x signal related to an amount of NO x downstream of said catalyst; means for producing a NO x error signal in dependence on a difference between said measured NO x signal and said setpoint; and means for adjusting the injecting of ammonia in response to said error signal in a direction and an amount to reduce said error signal.
Claim 9
Dependent Claim
225 words
Apparatus for controlling NO x emissions in a combined cycle plant of the type having a gas turbine producing a heated exhaust and a heat recovery steam generator through which said heated exhaust is passed for generation of steam therein, comprising: a catalyst in said heat recovery steam generator disposed for the passage of said exhaust therethrough; said catalyst being of the type which is effective to react NO x and ammonia to produce nitrogen and water for reduction of NO x in an effluent of said heat recovery steam generator; means for generating a predicted NO x signal based on at least a pressure, a temperature, an air flow and a fuel flow in said gas turbine; an ammonia control system responsive to said predicted NO x signal for injecting an amount of ammonia into said heated exhaust to react with said NO x to reduce said NO x downstream of said catalyst to a NO x setpoint; means for producing a measured NO x signal related to an amount of NO x downstream of said catalyst; means for producing a NO x error signal in dependence on a difference between said measured NO x signal and said setpoint; and means for adjusting the injecting of ammonia in response to said error signal in a direction and an amount to reduce said error signal.
Claim 10
Independent Claim
128 words
A method for controlling admission of ammonia into an exhaust gas stream from a combustion process upstream of a catalyst, comprising: predicting a predicted amount of NO x produced by said combustion process; injecting said ammonia into said exhaust gas stream at a rate effective to react in said catalyst with said predicted amount of NO x to produce a level of NO x downstream of said catalyst equal to a NO x setpoint; measuring an amount of NO x downstream of said catalyst to produce a measured NO x signal; comparing said measured NO x signal with said setpoint to produce a NO x error signal; and correcting said rate in dependence on said error to adjust said NO x downstream of said catalyst toward said setpoint.
Claim 11
Independent Claim
128 words
A method for controlling admission of ammonia into an exhaust gas stream from a combustion process upstream of a catalyst, comprising: predicting a predicted amount of NO x produced by said combustion process; injecting said ammonia into said exhaust gas stream at a rate effective to react in said catalyst with said predicted amount of NO x to produce a level of NO x downstream of said catalyst equal to a NO x setpoint; measuring an amount of NO x downstream of said catalyst to produce a measured NO x signal; comparing said measured NO x signal with said setpoint to produce a NO x error signal; and correcting said rate in dependence on said error to adjust said NO x downstream of said catalyst toward said setpoint.
Claim 12
Independent Claim
199 words
A method for controlling NO x emissions in a combined cycle plant of the type having a gas turbine producing a heated exhaust and a heat recovery steam generator through which said heated exhaust is passed for generation of steam therein, and a catalyst in said heat recovery steam generator disposed for the passage of said exhaust therethrough to produce nitrogen and water for reduction of NO x in an effluent of said heat recovery steam generator, comprising: generating a predicted NO x signal based on at least a pressure, a temperature, an air flow and a fuel flow in said gas turbine; injecting an amount of ammonia responsive to said predicted NO x signal into said heated exhaust to react with said NO x to reduce said NO x downstream of said catalyst to a NO x setpoint; producing a measured NO x signal related to an amount of NO x downstream of said catalyst; producing a NO x error signal in dependence on a difference between said measured NO x signal and said setpoint; and adjusting the injecting of ammonia in response to said error signal in a direction and an amount to reduce said error signal.
Claim 13
Independent Claim
199 words
A method for controlling NO x emissions in a combined cycle plant of the type having a gas turbine producing a heated exhaust and a heat recovery steam generator through which said heated exhaust is passed for generation of steam therein, and a catalyst in said heat recovery steam generator disposed for the passage of said exhaust therethrough to produce nitrogen and water for reduction of NO x in an effluent of said heat recovery steam generator, comprising: generating a predicted NO x signal based on at least a pressure, a temperature, an air flow and a fuel flow in said gas turbine; injecting an amount of ammonia responsive to said predicted NO x signal into said heated exhaust to react with said NO x to reduce said NO x downstream of said catalyst to a NO x setpoint; producing a measured NO x signal related to an amount of NO x downstream of said catalyst; producing a NO x error signal in dependence on a difference between said measured NO x signal and said setpoint; and adjusting the injecting of ammonia in response to said error signal in a direction and an amount to reduce said error signal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-09-25 | 1988-03-26 | 1988-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-25 | 1992-03-26 | 1992-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-25 | 1996-03-26 | 1996-09-25 | $7700.00 | Window Closed / Lapsed |