US4951579A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low NOX combustion process
Assignee: PETROCON ENGINEERING Inc
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Filing: 1989-03-03
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Granted: 1990-08-28
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Expires: 2009-03-03
Abstract
Abstract A process for low NOX combustion which involves combusting an oxygen-containing combustible gas stream having fuel material in excess of the oxygen in the combustible gas stream, whereby the combustible gas stream is combusted in a reducing atmosphere to produce a heated oxygen-depleted gaseous stream, converting at least a portion of the heat in the oxygen-depleted depleted stream into steam, adding air to the oxygen-depleted stream to produce a stoichiometric excess of oxygen in the resultant stream relative to fuel material present in the resultant stream, passing the resultant stream over the oxidizing catalyst to produce an oxidized gaseous stream, optionally removing heat from the oxidized stream, and venting the resultant cooled stream. A system for carrying out the foregoing process is also provided.
Inventors
- 👤 Ronald D. Bell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 08:47
CPC Classifications
F; F23; F23C; F23C13/00; F01; F01K; F01K23/00; F01K23/02; F01K23/06; F01K23/10; F01K23/103; F22; F22B; F22B1/00; F22B1/02; F22B1/18; F22B1/1861; F22B31/00; F23C6/00; F23C6/04; F23C6/042; F23C9/00; F23G; F23G5/00; F23G5/006; F23G5/44; F23G5/46; F23J; F23J15/00; F23J15/006; F23J2215/00; F23J2215/20; F23J2215/60; F23J2219/00; F23J2219/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
133 words
A process for low NOX steam-generating combustion which comprises combusting in a combustion zone at temperatures of at least 2000° F., a mixture of fuel and an oxygen source, wherein said mixture contains fuel in stoichiometric excess of the oxygen in said mixture, whereby said combustion takes place in a reducing atmosphere and produces heated oxygen-depleted gases, converting at least a portion of the heat in said oxygen-depleted gases into steam, thereby cooling said gases; forming said cooled oxygen-depleted gases into an effluent stream and adding air to said effluent stream to produce a stoichiometric excess of oxygen in the resultant stream relative to fuel present in said resultant stream, passing said resultant stream over an oxidizing catalyst to produce an oxidized gaseous stream, and passing the said oxidized stream on for venting.
Claim 2
Dependent Claim
133 words
A process for low NOX steam-generating combustion which comprises combusting in a combustion zone at temperatures of at least 2000° F., a mixture of fuel and an oxygen source, wherein said mixture contains fuel in stoichiometric excess of the oxygen in said mixture, whereby said combustion takes place in a reducing atmosphere and produces heated oxygen-depleted gases, converting at least a portion of the heat in said oxygen-depleted gases into steam, thereby cooling said gases; forming said cooled oxygen-depleted gases into an effluent stream and adding air to said effluent stream to produce a stoichiometric excess of oxygen in the resultant stream relative to fuel present in said resultant stream, passing said resultant stream over an oxidizing catalyst to produce an oxidized gaseous stream, and passing the said oxidized stream on for venting.
Claim 3
Dependent Claim
16 words
A process as defined in claim 1, wherein heat is removed from said oxidized gaseous stream.
Claim 4
Dependent Claim
24 words
A process as defined in claim 1, wherein said mixture is combusted in said combustion zone at a temperature of 2200° to 2600° F.
Claim 5
Dependent Claim
25 words
A process as defined in claim 1, wherein said mixture combusted in said combustion zone has a residence time of at least about 0.5 second.
Claim 6
Dependent Claim
25 words
A process as defined in claim 1, wherein said oxygen-depleted stream is cooled to a temperature of about 500° F. during said conversion to steam.
Claim 7
Dependent Claim
28 words
A process as defined in claim 1, wherein the space velocity of said resultant stream passing over said oxidizing catalyst is about 30,000 to 50,000 hr. -1 .
Claim 8
Dependent Claim
35 words
A process as defined in claim 1, wherein said air is added to said oxygen-depleted stream in an amount to provide a stoichiometric excess of oxygen present in the resultant stream of 10 to 50%.
Claim 9
Dependent Claim
25 words
A process as defined in claim 2, wherein the cooled gas vented to the atmosphere is at a temperature of about 300° to 400° F.
Claim 10
Dependent Claim
23 words
A process as defined in claim 1, wherein the gas vented to the atmosphere has a NOX content of less than 50 ppm.
Claim 11
Dependent Claim
38 words
A process in accordance with claim 1, wherein the temperatures in said combustion zone are in the range of 2200° to 2600° F. and said cooled effluent is in the range of from 400° to 550 ° F.
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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) | 1993-08-27 | 1994-02-26 | 1994-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-08-27 | 1998-02-26 | 1998-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-08-27 | 2002-02-26 | 2002-08-28 | $7700.00 | Window Closed / Lapsed |