US4507269A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Non-catalytic method for reducing the concentration of NO in combustion effluents by injection of ammonia at temperatures greater than about 1300 degree K
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1983-11-10
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Granted: 1985-03-26
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Expires: 2003-11-10
Abstract
Abstract Disclosed is a process for non-catalytically removing NO from combustion effluent streams at temperatures from about 1300 DEG K. to 1600 DEG K. by injecting ammonia immediately before or directly into a zone where the combustion effluent is cooling at a rate of at least about 250 DEG K.
Inventors
- 👤 Anthony M. Dean
- 👤 Anthony J. DeGregoria
- 👤 James E. Hardy
- 👤 Boyd E. Hurst
- 👤 Richard K. Lyon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:03
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/54; B01D53/56
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
142 words
In a process for reducing NO concentration of a combustion effluent wherein ammonia is injected into a flowing combustion effluent containing NO and at least 0.1 volume percent oxygen when at least a portion of the effluent is at a temperature within the range of about 1300° K. to 1600° K. and wherein the combustion effluent passes through at least one cooling zone in which it is cooling at a rate of at least about 250° K. per second, the improvement which comprises injecting ammonia into the combustion effluent at a point where the combustion effluent: (a) is at a temperature of about 1300° K. to 1600° K. and (b) is cooling at a rate of at least about 250° K. per second, wherein the amount of ammonia injected is such that a reduction of NO in the combustion effluent is realized.
Claim 2
Dependent Claim
142 words
In a process for reducing NO concentration of a combustion effluent wherein ammonia is injected into a flowing combustion effluent containing NO and at least 0.1 volume percent oxygen when at least a portion of the effluent is at a temperature within the range of about 1300° K. to 1600° K. and wherein the combustion effluent passes through at least one cooling zone in which it is cooling at a rate of at least about 250° K. per second, the improvement which comprises injecting ammonia into the combustion effluent at a point where the combustion effluent: (a) is at a temperature of about 1300° K. to 1600° K. and (b) is cooling at a rate of at least about 250° K. per second, wherein the amount of ammonia injected is such that a reduction of NO in the combustion effluent is realized.
Claim 3
Dependent Claim
23 words
The process of claim 1 wherein about 0.4 to 10 moles of ammonia is injected per mole of NO of the combustion effluent.
Claim 4
Dependent Claim
23 words
The process of claim 2 wherein about 1 to 3 moles of ammonia is injected per mole of NO of the combustion effluent.
Claim 5
Dependent Claim
26 words
The process of claim 2 wherein the cooling zone in which the ammonia is injected is cooling at a rate of at least about 1000° K./sec.
Claim 6
Dependent Claim
19 words
The process of claim 4 wherein at least 0.25 volume percent of oxygen is present in the combustion effluent.
Claim 7
Dependent Claim
138 words
In a process for reducing NO concentration of a combustion effluent containing NO and at least 0.1 volume percent oxygen when at least a portion of the combustion effluent is at a temperature within the range of about 1300° K. to 1600° K. and wherein the combustion effluent passes through at least one cooling zone in which it is cooling at a rate of at least about 250° K. per second, the improvement which comprises injecting enough ammonia into the combustion effluent at a point upstream from a cooling zone having a cooling rate of at least about 250° K. where the temperature of the combustion effluents is from about 1300° K. to 1600° K. such that when the combustion effluent reaches said cooling zone in it contains at least 0.4 moles of ammonia per mole of NO.
Claim 8
Dependent Claim
138 words
In a process for reducing NO concentration of a combustion effluent containing NO and at least 0.1 volume percent oxygen when at least a portion of the combustion effluent is at a temperature within the range of about 1300° K. to 1600° K. and wherein the combustion effluent passes through at least one cooling zone in which it is cooling at a rate of at least about 250° K. per second, the improvement which comprises injecting enough ammonia into the combustion effluent at a point upstream from a cooling zone having a cooling rate of at least about 250° K. where the temperature of the combustion effluents is from about 1300° K. to 1600° K. such that when the combustion effluent reaches said cooling zone in it contains at least 0.4 moles of ammonia per mole of NO.
Claim 9
Dependent Claim
28 words
The process of claim 6 wherein the combustion effluent contains from about 1 to 3 moles of ammonia per mole of NO when it reaches the cooling zone.
Claim 10
Dependent Claim
19 words
The process of claim 6 wherein at least 0.25 volume percent of oxygen is present in the combustion effluent.
Claim 11
Dependent Claim
18 words
The process of claim 6 wherein the ammonia is injected within 10.4 seconds upstream from the cooling zone.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-03-25 | 1988-09-24 | 1989-03-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-03-25 | 1992-09-24 | 1993-03-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-03-25 | 1996-09-24 | 1997-03-26 | $7700.00 | Window Closed / Lapsed |