Patent US5359967A successfully refreshed from Google Patents.
US5359967A
Expired / Lapsed
US
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Combined thermal and fuel NOx control utilizing furnace cleanliness and stoichiometric burner combustion
Assignee: Diamond Power International Inc
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Filing: 1993-06-15
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Granted: 1994-11-01
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Expires: 2013-06-15
Abstract
Abstract A method for controlling nitrogen oxides (NO x ) levels in a gas produced by a fossil fuel fired unit comprises establishing an optimum gas temperature range for the unit and monitoring a gas temperature of the unit. The heat exchanger surfaces of the unit are then cleaned until the monitored gas temperature is within the optimum gas temperature range. An optimum fuel combustion rate range is also established for the unit and a fuel combustion rate of the unit is monitored. Air is provided to the unit until the monitored fuel combustion rate is within the optimum combustion rate range.
Inventors
- 👤 Hudson R. Carter
- 👤 John T. Huston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:29
CPC Classifications
F; F23; F23N; F23N5/00; F23N5/02; F23N5/08; F23N5/082; F22; F22B; F22B37/00; F22B37/02; F22B37/56; F23J; F23J3/00; F23N1/00; F23N1/02; F23N2223/00; F23N2223/08; F23N2225/00; F23N2225/08; F23N2225/10; F23N5/24
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
97 words
A method for controlling nitrogen oxide (NO x ) levels in a gas produced by a fossil fuel fired unit, the method comprising: establishing an optimum gas temperature range for the unit; monitoring a gas temperature of the unit; cleaning the heat exchanger surfaces of the unit until the monitored gas temperature is within the optimum gas temperature range; establishing an optimum fuel combustion rate range for the unit; monitoring a fuel combustion rate of the unit; and providing air to the unit until the monitored fuel combustion rate is within the optimum fuel combustion rate range.
Claim 2
Independent Claim
97 words
A method for controlling nitrogen oxide (NO x ) levels in a gas produced by a fossil fuel fired unit, the method comprising: establishing an optimum gas temperature range for the unit; monitoring a gas temperature of the unit; cleaning the heat exchanger surfaces of the unit until the monitored gas temperature is within the optimum gas temperature range; establishing an optimum fuel combustion rate range for the unit; monitoring a fuel combustion rate of the unit; and providing air to the unit until the monitored fuel combustion rate is within the optimum fuel combustion rate range.
Claim 3
Dependent Claim
13 words
The method according to claim 1, including establishing combustion segments for the unit.
Claim 4
Dependent Claim
40 words
The method according to claim 2, wherein a fuel combustion rate is monitored for each segment and air is provided to each segment of the unit until the monitored fuel combustion rate is within the optimum fuel combustion rate range.
Claim 5
Dependent Claim
12 words
The method according to claim 2, wherein each segment comprises a burner.
Claim 6
Dependent Claim
18 words
The method according to claim 1, wherein the heat exchanger surfaces of the unit are cleaned by blowers.
Claim 7
Dependent Claim
18 words
The method according to claim 1, wherein the heat exchanger surfaces of the unit are cleaned by water.
Claim 8
Independent Claim
163 words
A system for controlling nitrogen oxides (NO x ) levels in a gas produced by a fossil fuel fired unit having heat exchanger surfaces, the system comprising: burning means in the unit for burning the fuel at a combustion rate; air means for providing air to the unit; cleaning means for cleaning the heat exchanger surfaces of the unit; and monitoring means for setting an optimum combustion rate range for the unit and for measuring the combustion rate produced by the burning means, the monitoring means communicating with the air means for adjusting the measured combustion rate within the combustion rate range by providing air to the unit, the monitoring means also for setting an optimum gas temperature range for the unit and for measuring a gas temperature of the unit, the monitoring means also communicating with the cleaning means for adjusting the gas temperature of the unit within the optimum gas temperature range by cleaning the heat exchanger surfaces of the unit.
Claim 9
Independent Claim
163 words
A system for controlling nitrogen oxides (NO x ) levels in a gas produced by a fossil fuel fired unit having heat exchanger surfaces, the system comprising: burning means in the unit for burning the fuel at a combustion rate; air means for providing air to the unit; cleaning means for cleaning the heat exchanger surfaces of the unit; and monitoring means for setting an optimum combustion rate range for the unit and for measuring the combustion rate produced by the burning means, the monitoring means communicating with the air means for adjusting the measured combustion rate within the combustion rate range by providing air to the unit, the monitoring means also for setting an optimum gas temperature range for the unit and for measuring a gas temperature of the unit, the monitoring means also communicating with the cleaning means for adjusting the gas temperature of the unit within the optimum gas temperature range by cleaning the heat exchanger surfaces of the unit.
Claim 10
Dependent Claim
17 words
The system according to claim 7, wherein monitoring means comprises a gas temperature sensor in the unit.
Claim 11
Dependent Claim
19 words
The system according to claim 8, wherein the monitoring means further comprises a combustion rate sensor in the unit.
Claim 12
Dependent Claim
20 words
The system according to claim 9, wherein the monitoring means further comprises display means for displaying temperatures and combustion rates.
Claim 13
Dependent Claim
18 words
The system according to claim 9, wherein the cleaning means comprises at least one blower in the unit.
Claim 14
Dependent Claim
17 words
The system according to claim 9, wherein the cleaning means further comprises at least one water lance.
Claim 15
Dependent Claim
15 words
The system according to claim 7, wherein the burning means comprises at least one burner.
References Cited (Backward Citations)
US4475482A
Cited
US5181482A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-10-31 | 1998-05-02 | 1998-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-10-31 | 2002-05-02 | 2002-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-10-31 | 2006-05-02 | 2006-11-01 | $7700.00 | Window Closed / Lapsed |