Patent US3948223A successfully refreshed from Google Patents.
US3948223A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Serially fired steam generator
Assignee: Foster Wheeler Energy Corp
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Filing: 1975-01-02
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Granted: 1976-04-06
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Expires: 1995-01-02
Abstract
Abstract A steam generator consists of several units in which combustion air is mixed with fuel at furnace sections placed in series. An excess of combustion air is used in the first furnace section and the exhaust gases which include unused combustion air are led into another furnace where fuel is added in sufficient quantities to use at least a portion of the combustion air which was not used in said first furnace.
Inventors
- 👤 Elliot Warren Benson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:50
CPC Classifications
F; F22; F22B; F22B33/00; F23; F23C; F23C6/00; F23C6/04; F23C6/042
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
163 words
The method of producing heat energy comprising the steps of: providing fuel; providing combustion air considerably in excess of that which is required for complete combustion at a first combustion zone; burning the mixture of fuel and excess combustion air in said first combustion zone; leading the exhaust gases including the excess combustion air from the first combustion zone to a second combustion zone; adding combustion air, in addition to that contained in the exhaust gases from the first combustion zone at said second combustion zone; providing additional fuel to be burned at said second combustion zone; burning said additional fuel in the presence of the exhaust gases from said first combustion zone and in the presence of said added combustion air; whereby the excess combustion air furnished at said first combustion zone and the exhaust gases furnished at said second combustion zone will prevent the temperatures within said combustion zones from rising above that at which oxides of nitrogen are substantially produced.
Claim 2
Independent Claim
163 words
The method of producing heat energy comprising the steps of: providing fuel; providing combustion air considerably in excess of that which is required for complete combustion at a first combustion zone; burning the mixture of fuel and excess combustion air in said first combustion zone; leading the exhaust gases including the excess combustion air from the first combustion zone to a second combustion zone; adding combustion air, in addition to that contained in the exhaust gases from the first combustion zone at said second combustion zone; providing additional fuel to be burned at said second combustion zone; burning said additional fuel in the presence of the exhaust gases from said first combustion zone and in the presence of said added combustion air; whereby the excess combustion air furnished at said first combustion zone and the exhaust gases furnished at said second combustion zone will prevent the temperatures within said combustion zones from rising above that at which oxides of nitrogen are substantially produced.
Claim 3
Dependent Claim
58 words
The method defined in claim 1 comprising the further steps of placing said exhaust gases from said first combustion zone in indirect heat exchange with water to produce steam before said exhaust gases from said first combustion zone are led to said second combustion zone and using the heat produced in said second combustion zone to superheat steam.
Claim 4
Independent Claim
134 words
An apparatus for producing heat energy comprising: a first unit having a first combustion zone; a second unit having a second combustion zone; means for supplying fuel and an amount of combustion air considerably in excess of that required to complete the combustion of said fuel to said first combustion zone; means for flowing the exhaust gas from said first combustion zone into said second combustion zone; means for adding fuel to said second combustion zone to combust said fuel in the presence of the exhaust gases from said first combustion zone; tubes in said first unit for flowing water close to said first combustion zone so that said water is heated and generated into steam; and a superheater, said superheater being disposed in said second unit and heated by said second combustion zone.
Claim 5
Independent Claim
134 words
An apparatus for producing heat energy comprising: a first unit having a first combustion zone; a second unit having a second combustion zone; means for supplying fuel and an amount of combustion air considerably in excess of that required to complete the combustion of said fuel to said first combustion zone; means for flowing the exhaust gas from said first combustion zone into said second combustion zone; means for adding fuel to said second combustion zone to combust said fuel in the presence of the exhaust gases from said first combustion zone; tubes in said first unit for flowing water close to said first combustion zone so that said water is heated and generated into steam; and a superheater, said superheater being disposed in said second unit and heated by said second combustion 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) | 1979-04-06 | 1979-10-06 | 1980-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-06 | 1983-10-06 | 1984-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-06 | 1987-10-06 | 1988-04-06 | $7700.00 | Window Closed / Lapsed |