US4590868A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coal-fired combined plant
Assignee: Mitsubishi Heavy Industries Ltd
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Filing: 1985-02-22
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Granted: 1986-05-27
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Expires: 2005-02-22
Abstract
Abstract In a coal-fired combined plant, finely powdered coal is burned at high temperature in a pressurized coal-melting combustion furnace to obtain combustion gas substantially free of dust to drive a gas turbine in order to generate electric power. Waste gas from the gas turbine is used to produce steam which drives a steam turbine for additional electric power generation. Primary dust removal from the combustion gas is carried out by removing most of the resulting coal ash in a molten state. In a secondary dust removal, the dust is removed from the combustion gas by a cyclone disposed in the combustion furnace. In a tertiary dust removal, the dust is removed from the combustion gas which is discharged through an outlet at the combustion furnace by a precision dust-removing device.
Inventors
- 👤 Takao Ishihara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:55
CPC Classifications
F; F23; F23J; F23J15/00; F23J15/02; F23J15/022; F23J15/027; F01; F01K; F01K23/00; F01K23/02; F01K23/06; F01K23/067; F23C; F23C3/00; F23C3/006; F23C6/00; Y; Y02; Y02E; Y02E20/00; Y02E20/16; Y02E20/18
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
256 words
A coal-fired combined plant in which a finely powdered coal is carried to a combustion furnace by high-temperature and high-pressure air and is burned therein; the resultant combustion gas is delivered to a gas turbine, in order to generate electric power; by the utilization of the resultant exhaust gas, steam is produced; and electric power generation is carried out by a steam turbine with the aid of the produced steam, characterized in that high-temperature and high-pressure air and a finely powdered coal are introduced into coal ash-melting combustion furnaces, in which said finely powdered coal is burned at a high temperature to produce a combustion gas; most of the resultant coal ash is removed in a molten state from said combustion gas to carry out a primary dust removal; a dust in said combustion gas is removed therefrom by a cyclone disposed in a pressurizing coal combustion furnace to carry out a secondary dust removal; the removed dust is subjected to a heat exchange for secondary air in a dust cooler disposed on the lower portion of said pressurizing coal combustion furnace; a temperature of said combustion gas at an outlet of said pressurizing coal combustion furnace is adjusted to a predetermined level by mixing said combustion gas with said secondary air; the dust in said combustion gas discharged through the outlet of said pressurizing coal combustion furnace is removed therefrom by a precision dust-removing device in order to carry out a tertiary dust removal; and said combustion gas is then delivered to said gas turbine.
Claim 2
Dependent Claim
256 words
A coal-fired combined plant in which a finely powdered coal is carried to a combustion furnace by high-temperature and high-pressure air and is burned therein; the resultant combustion gas is delivered to a gas turbine, in order to generate electric power; by the utilization of the resultant exhaust gas, steam is produced; and electric power generation is carried out by a steam turbine with the aid of the produced steam, characterized in that high-temperature and high-pressure air and a finely powdered coal are introduced into coal ash-melting combustion furnaces, in which said finely powdered coal is burned at a high temperature to produce a combustion gas; most of the resultant coal ash is removed in a molten state from said combustion gas to carry out a primary dust removal; a dust in said combustion gas is removed therefrom by a cyclone disposed in a pressurizing coal combustion furnace to carry out a secondary dust removal; the removed dust is subjected to a heat exchange for secondary air in a dust cooler disposed on the lower portion of said pressurizing coal combustion furnace; a temperature of said combustion gas at an outlet of said pressurizing coal combustion furnace is adjusted to a predetermined level by mixing said combustion gas with said secondary air; the dust in said combustion gas discharged through the outlet of said pressurizing coal combustion furnace is removed therefrom by a precision dust-removing device in order to carry out a tertiary dust removal; and said combustion gas is then delivered to said gas turbine.
Claim 3
Dependent Claim
34 words
The coal-fired combined plant according to claim 1 wherein in the step of said primary dust removal, 90 to 95% of the coal ash is removed in a molten state from said combustion gas.
Claim 4
Dependent Claim
34 words
The coal-fired combined plant according to claim 1 wherein said coal ash-melting combustion furnaces are connected to said pressurizing coal combustion furnace in a tangential direction to a furnace wall of the latter furnace.
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) | 1989-05-26 | 1989-11-25 | 1990-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-05-26 | 1993-11-25 | 1994-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-05-26 | 1997-11-25 | 1998-05-27 | $7700.00 | Window Closed / Lapsed |