Patent US3729285A successfully refreshed from Google Patents.
US3729285A
Expired / Lapsed
US
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Burner and method of operating it to control the production of nitrogen oxides
Assignee: SCHWEDERSKY
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Filing: 1972-05-22
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Granted: 1973-04-24
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Expires: 1992-05-22
Abstract
Abstract In the operation of a burner using gaseous fuel the production of nitrogen oxides is limited and controlled by providing successive stages of combustion and by holding down the temperature of combustion. This is accomplished by introducing the fuel in two streams of unequal volume and comprising respectively more and less than the stoichiometric percentage of air, igniting the streams in sequence, thus effecting first and second stages of combustion, and mixing and consuming the excess fuel and air of said streams respectively, thus effecting a third stage of combustion.
Inventors
- 👤 G Schwedersky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:26
CPC Classifications
C; C21; C21C; C21C5/00; C21C5/52; C21C5/5211; C21C5/5217; F; F23; F23C; F23C6/00; F23C6/04; F23C6/045; F23C6/047; F23D; F23D14/00; F23D14/20; F23D14/22; F23C2201/00; F23C2201/20; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
38 words
The method claimed in claim 1 in which one of said streams is of greater volume than the other, and the sum of the percentages of air in the two streams approximates the optimum or stoichiometric air percentage.
Claim 2
Dependent Claim
96 words
A burner adapted to provide combustion of gaseous fuel and air in successive stages which comprises: gaseous fuel and air conduits, a burner tile chamber, a perforate choke collar within the burner tile chamber, an ignition means disposed at the burner face, conduit and orifice meanS for injecting a first stream of mixed gaseous fuel and air into the choke collar within the burner tile chamber, and other conduit and orifice means for injecting a second stream of mixed gaseous fuel and air into the burner tile chamber to pass over and around the choke collar.
Claim 3
Dependent Claim
25 words
The burner claimed in claim 3 in which the said conduits are concentric and the choke collar is axially aligned with the center conduit means.
Claim 4
Dependent Claim
130 words
In the operation of a burner using a gaseous fuel/air mixture which when burned forms nitrogen oxides, the concentration of the nitrogen oxides being greatest when the volume of air employed is substantially the optimum for combustion and therefor when burned has a high temperature, the step of minimizing the temperature of combustion and the formation of the nitrogen oxides by providing multistage combustion at successive distances from the burner face said multistage combustion being achieved by dividing the gaseous fuel/air supply into two streams, one of the streams comprising excess air and the other stream comprising excess gaseous fuel, igniting the said two streams in successive stages and thereafter mixing and burning the remaining excess air and excess fuel from said streams respectively providing a third stage of combustion.
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) | 1976-04-23 | 1976-10-23 | 1977-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-23 | 1980-10-23 | 1981-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-23 | 1984-10-23 | 1985-04-24 | $7700.00 | Window Closed / Lapsed |