US3660054A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coal upgrading
Assignee: Atlantic Richfield Co
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Filing: 1970-09-29
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Granted: 1972-05-02
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Expires: 1990-09-29
Abstract
Abstract A method for upgrading coal to a higher quality fuel or feed stock by mixing coal with water and heating the mixture in a nonoxidizing atmosphere at a temperature near the critical temperature of water and under a pressure sufficient to maintain substantially all of the water in the liquid state. By this process at least the sulfur and/or ash content of the coal is reduced.
Inventors
- 👤 Robert W Rieve
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:06
CPC Classifications
C; C10; C10L; C10L9/00
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
21 words
A method according to claim 1 wherein said pressure is in the range of from about 1,545 to about 3,226 p.s.i.a.
Claim 2
Dependent Claim
24 words
A method according to claim 1 wherein said coal is subdivided to be substantially all no greater than about 1 inch effective diameter particles.
Claim 3
Dependent Claim
53 words
A method according to claim 1 wherein said coal is at least one of bituminous and lignite and is subdivided to be substantially all no greater than about 1 inch effect diameter particles, said temperature is from about 650* to about 706* F., and said time is for at least about 1 minute.
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) | 1975-05-02 | 1975-11-01 | 1976-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-02 | 1979-11-01 | 1980-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-02 | 1983-11-01 | 1984-05-02 | $7700.00 | Window Closed / Lapsed |