US4928478A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water and steam injection in cogeneration system
Assignee: General Electric Co
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Filing: 1985-07-22
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Granted: 1990-05-29
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Expires: 2005-07-22
Abstract
Abstract A control system for a cogeneration plant measures the flow of steam exceeding the requirements of the steam-using process. Water is injected into the combustion zone of a combustor of the gas turbine portion of the cogeneration system to provide a predetermined reduction in NOx products. The excess steam is added to the output of the compressor portion of the gas turbine to augment the gas turbine power output due to the augmented mass flow. The control system reduces the water injection in proportion to the steam flow to maintain the total water flow to the combustion zone at a level which maintains the preferred level of NOx reduction. In a second embodiment, the excess steam is first injected into the combustion zone with a one-for-one equivalent reduction in water injection. When the excess steam exceeds the amount required for NOx reduction, the excess is added to the output of the air compressor for power augmentation. As the power augmentation steam is added a proportionate reduction is made in the NOx reduction steam to account for the fact that a fraction of the output of the air compressor passes through the combustion zone.
Inventors
- 👤 Chris E. Maslak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:03
CPC Classifications
F; F01; F01K; F01K21/00; F01K21/04; F01K21/047; F01N; F01N13/00; F01N13/08; F01N3/00; F01N3/06; F02; F02C; F02C3/00; F02C3/20; F02C3/30; Y; Y02; Y02E; Y02E20/00; Y02E20/14; Y10; Y10S; Y10S55/00; Y10S55/30
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
164 words
A cogeneration system comprising: a gas turbine having an air compressor, a combustor and a turbine effective for producing an output torque and a flow of hot gasses; a heat recovery steam generator effective for absorbing heat energy from said flow of hot gasses and for producing steam; means for injecting at least one of a steam and a water into a combustion zone of said combustor at a flow effective for producing a predetermined level of reduction in a NOx in said flow of hot gasses; means for adding at least a part of an excess steam from said heat recovery steam generator to a compressed air from said air compressor whereby power output of said gas turbine is augmented; and means for reducing said at least one of a steam and a water in a proportion to said excess steam added to said compressed air effective to maintain said predetermined level of reduction in a NOx in said flow of hot gasses.
Claim 2
Dependent Claim
164 words
A cogeneration system comprising: a gas turbine having an air compressor, a combustor and a turbine effective for producing an output torque and a flow of hot gasses; a heat recovery steam generator effective for absorbing heat energy from said flow of hot gasses and for producing steam; means for injecting at least one of a steam and a water into a combustion zone of said combustor at a flow effective for producing a predetermined level of reduction in a NOx in said flow of hot gasses; means for adding at least a part of an excess steam from said heat recovery steam generator to a compressed air from said air compressor whereby power output of said gas turbine is augmented; and means for reducing said at least one of a steam and a water in a proportion to said excess steam added to said compressed air effective to maintain said predetermined level of reduction in a NOx in said flow of hot gasses.
Claim 3
Dependent Claim
41 words
A cogeneration system according to claim 1 wherein said at least one of a steam and a water includes a steam and a water in a flow which, together, is effective for producing said predetermined level of reduction in a NOx.
Claim 4
Dependent Claim
53 words
A cogeneration system according to claim 2 wherein said system further includes means for first substituting said excess steam for said water and simultaneously reducing said water in proportion to said excess steam until said excess steam is sufficient to maintain said predetermined level of reduction in a NOx without requiring said water.
Claim 5
Dependent Claim
49 words
A cogeneration system according to claim 3 wherein said means for adding at least a part of an excess steam to said compressed air is effective only after said excess steam is at least sufficient to maintain said predetermined level of reduction in a NOx without requiring said water.
Claim 6
Dependent Claim
43 words
A cogeneration system according to claim 1 further comprising means for limiting a flow of said excess steam added to said compressed air to a value which does not exceed an amount required for maintaining said predetermined level of reduction in a NOx.
Claim 7
Independent Claim
176 words
A method for controlling a cogeneration system of a type including a gas turbine and a heat recovery steam generator, said gas turbine including an air compressor, a combustor and a turbine effective, in combination, for producing a torque, and a quantity of hot gasses, said heat recovery steam generator being effective to absorb heat energy from said quantity of hot gasses for producing steam, the method comprising: injecting at least one of a steam and a water into a combustion zone of said combustor at a flow effective for producing a predetermined level of reduction in a NOx in said quantity of hot gasses; adding at least part of an excess steam from said heat recovery steam generator to compressed air from said air compressor whereby power output of said gas turbine is augmented; and reducing said at least one of a steam and a water in a proportion to said excess steam added to said compressed air effective to maintain said predetermined level of reduction in a NOx in said quantity of hot gasses.
Claim 8
Independent Claim
176 words
A method for controlling a cogeneration system of a type including a gas turbine and a heat recovery steam generator, said gas turbine including an air compressor, a combustor and a turbine effective, in combination, for producing a torque, and a quantity of hot gasses, said heat recovery steam generator being effective to absorb heat energy from said quantity of hot gasses for producing steam, the method comprising: injecting at least one of a steam and a water into a combustion zone of said combustor at a flow effective for producing a predetermined level of reduction in a NOx in said quantity of hot gasses; adding at least part of an excess steam from said heat recovery steam generator to compressed air from said air compressor whereby power output of said gas turbine is augmented; and reducing said at least one of a steam and a water in a proportion to said excess steam added to said compressed air effective to maintain said predetermined level of reduction in a NOx in said quantity of hot gasses.
References Cited (Backward Citations)
CH243692A
Cited
FR1007140A
Cited
FR1168070A
Cited
US3731485A
Cited
US3708976A
Cited
US3693347A
Cited
JPS5338808A
Cited
US4466241A
Cited
US4466241B1
Cited
JPS5535108A
Cited
US4259837A
Cited
US4519207A
Cited
JPS5977041A
Cited
JPS5982531A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-05-28 | 1993-11-27 | 1994-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-28 | 1997-11-27 | 1998-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-28 | 2001-11-27 | 2002-05-29 | $7700.00 | Window Closed / Lapsed |