Patent US4409786A successfully refreshed from Google Patents.
US4409786A
Expired / Lapsed
US
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Wood burning system and method
Assignee: NELSON EDWARD W
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Filing: 1979-03-21
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Granted: 1983-10-18
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Expires: 1999-03-21
Abstract
Abstract A system and method provides for burning wood particles or other combustible fibrous particles at a continuous high rate in which the particles are at least partially pyrolyzed as they are being fed into a combustion chamber, complete combustion of the particles and pyrolysis products occuring within the combustion chamber. Pyrolysis is enabled by mixing the particles with air having a temperature of at least 600° F. The system enables the burning of green wood in existing large boiler systems as well as in gas turbine systems; the latter operatable with a high pressure combustion chamber. In a boiler system, air for pyrolysis of the particles may be heated by the boiler, in a turbine system, air for pyrolysis of the particles may be heated by a compressor driven by a turbine.
Inventors
- 👤 Joseph T. Hamrick
- 👤 Leslie C. Rose
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:05
CPC Classifications
F; F23; F23J; F23J15/00; F23J15/02; F23J15/022; F23J15/027; F02; F02C; F02C3/00; F02C3/20; F02C3/26; F02C3/28; F23C; F23C6/00; F23C7/00; F23C7/02; F23C7/06; F23G; F23G5/00; F23G5/02; F23G5/027; F23G5/0276; F23G7/00; F23G7/10; F23G7/105; F23K; F23K3/00; F23L; F23L15/00; F23L2900/00; F23L2900/15042; Y; Y02; Y02E; Y02E20/00; Y02E20/34; Y02T; Y02T50/00; Y02T50/60
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
186 words
A system for burning fibrous particles, comprising: a combustion chamber; a turbine; injecting means for feeding fibrous particles into the combustion chamber in a substantially continuous manner; pyrolysis means for pre-combustion heating the particles as the particles are being fed into the combustion chamber and for pyrolyzing at least some of the particles to form pyrolysis products, said pyrolysis products being fed into the combination chamber with unpyrolyzed particles; said pyrolysis means including an air compressor mechanically driven by the turbine and means for mixing compressed air with the particles as the particles are being fed into the combustion chamber, said pyrolysis means further including means for heating the compressed air before mixing of the compressed air with the particles, the means for heating the compressed air including means for passing the compressed air over an exterior surface of the combustion chamber; means for igniting the particles and pyrolysis products in the combustion chamber; means for injecting air into the combustion chamber for enabling combustion of the particles and pyrolysis products therein to form combustion gases; and, means for injecting the combustion gases into the turbine.
Claim 2
Independent Claim
186 words
A system for burning fibrous particles, comprising: a combustion chamber; a turbine; injecting means for feeding fibrous particles into the combustion chamber in a substantially continuous manner; pyrolysis means for pre-combustion heating the particles as the particles are being fed into the combustion chamber and for pyrolyzing at least some of the particles to form pyrolysis products, said pyrolysis products being fed into the combination chamber with unpyrolyzed particles; said pyrolysis means including an air compressor mechanically driven by the turbine and means for mixing compressed air with the particles as the particles are being fed into the combustion chamber, said pyrolysis means further including means for heating the compressed air before mixing of the compressed air with the particles, the means for heating the compressed air including means for passing the compressed air over an exterior surface of the combustion chamber; means for igniting the particles and pyrolysis products in the combustion chamber; means for injecting air into the combustion chamber for enabling combustion of the particles and pyrolysis products therein to form combustion gases; and, means for injecting the combustion gases into the turbine.
Claim 3
Independent Claim
172 words
A system for burning fibrous particles comprising: a pressurized combustion chamber; a turbine; injecting means for feeding fibrous particles into the pressurized combustion chamber in a substantially continuous manner; pyrolysis means including an air compressor, drive by the turbine, for compressional air heating and mixing means upstream of the combustion chamber for mixing the compressionally heated air with the particles as the particles are being fed into the combustion chamber and for thereby pyrolyzing at least some of the particles to form pyrolysis products, said pyrolysis products being fed into the combustion chamber with unpyrolyzed particles, said pyrolysis means including pressurized duct means for feeding air, compressionally heated by the compressor, into the mixing means, said duct means enclosing the combustion chamber; means for igniting the unpyrolyzed particles and pyrolysis products in the combustion chamber; means for injecting air into the combustion chamber for enabling combustion of the unpyrolyzed particles and pyrolysis products therein to form combustion gases; and, means for injecting the combustion gases into the turbine to enable operation thereof.
Claim 4
Independent Claim
172 words
A system for burning fibrous particles comprising: a pressurized combustion chamber; a turbine; injecting means for feeding fibrous particles into the pressurized combustion chamber in a substantially continuous manner; pyrolysis means including an air compressor, drive by the turbine, for compressional air heating and mixing means upstream of the combustion chamber for mixing the compressionally heated air with the particles as the particles are being fed into the combustion chamber and for thereby pyrolyzing at least some of the particles to form pyrolysis products, said pyrolysis products being fed into the combustion chamber with unpyrolyzed particles, said pyrolysis means including pressurized duct means for feeding air, compressionally heated by the compressor, into the mixing means, said duct means enclosing the combustion chamber; means for igniting the unpyrolyzed particles and pyrolysis products in the combustion chamber; means for injecting air into the combustion chamber for enabling combustion of the unpyrolyzed particles and pyrolysis products therein to form combustion gases; and, means for injecting the combustion gases into the turbine to enable operation thereof.
Claim 5
Dependent Claim
26 words
The system of claim 2 further including second duct means for separating ash from the combustion gases before injection of the combustion gases into the turbine.
Claim 6
Dependent Claim
29 words
The system of claim 3 wherein the second duct means includes valve means, disposed remotely from said combustion chamber for removal of the ash from the second duct means.
Claim 7
Dependent Claim
36 words
The system of claim 4 wherein the duct means is configured for causing the compressed air to circulate past the combustion chamber for heating of the compressed air before it is fed into the combustion chamber.
Claim 8
Dependent Claim
56 words
The system of claim 2, wherein the injecting means includes a plurality of interconnected hoppers and means for selectively pressurizing at least one of the hoppers to enable the movement of wood particles from a first hopper at atmospheric pressure to a last hopper at a pressure subsequently equal to the pressure of the combustion chamber.
Claim 9
Dependent Claim
26 words
The system of claim 6 wherein the injecting means includes screw feeder means for moving the wood particles from the last hopper into the combustion chamber.
Claim 10
Dependent Claim
27 words
The system of claim 7 wherein the injecting means includes pneumatically operated gate means for enabling movement of the wood particles from one hopper to another hopper.
Claim 11
Dependent Claim
45 words
The wood burning gas turbine apparatus of claim 8 wherein the injecting means including means for feeding pressurized air from the air compressor to the pneumatically operated gate means and cooling means for cooling said pressurized air before it is fed to the gate means.
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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) | 1986-10-17 | 1987-04-18 | 1987-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-17 | 1991-04-18 | 1991-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-17 | 1995-04-18 | 1995-10-18 | $7700.00 | Window Closed / Lapsed |