US3896557A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for drying and stabilizing coal
Assignee: Sunoco Inc
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Filing: 1974-05-09
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Granted: 1975-07-29
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Expires: 1994-05-09
Abstract
Abstract A process for drying lignitic and subbituminous coal containing from about 25 to about 40% by weight water which comprises heating said coal with a fluidizing combustion gas stream containing from about 7 to about 9% by volume of oxygen to reduce the moisture content to a level of from about 8 to about 12% whereby said coal is also stabilized against spontaneous combustion.
Inventors
- 👤 Walter H Seitzer
- 👤 William S Bradley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:27
CPC Classifications
C; C10; C10F; C10F5/00; C10L; C10L9/00; C10L9/02; C10L9/06; F; F26; F26B; F26B3/00; F26B3/02; F26B3/06; F26B3/08
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
65 words
A PROCESS FOR DRYING LIGNITIC AND SUBBITUMINOUS COAL CONTAINING FROM ABOUT 25 PERCENTTO ABOUT 40% BY WEIGHT WATER WHICH COMPRISES HEATING SAID COAL WITH A FLUIDIZING COMBUSTION GAS STREAM CONTAINING FROM ABOUT 7 PERCENT TO ABOUT 9% BY VOLUME OF OXYGEN TO REDUCE THE MOISTURE CONTENT TO A LEVEL OF FROM ABOUT 8 TO ABOUT 12% WHEREBY SAID COAL IS ALSO STABILIZED AGAINST SPONTANEOUS COMBUSTION.
Claim 2
Dependent Claim
65 words
A PROCESS FOR DRYING LIGNITIC AND SUBBITUMINOUS COAL CONTAINING FROM ABOUT 25 PERCENTTO ABOUT 40% BY WEIGHT WATER WHICH COMPRISES HEATING SAID COAL WITH A FLUIDIZING COMBUSTION GAS STREAM CONTAINING FROM ABOUT 7 PERCENT TO ABOUT 9% BY VOLUME OF OXYGEN TO REDUCE THE MOISTURE CONTENT TO A LEVEL OF FROM ABOUT 8 TO ABOUT 12% WHEREBY SAID COAL IS ALSO STABILIZED AGAINST SPONTANEOUS COMBUSTION.
Claim 3
Dependent Claim
21 words
The process of claim 1 where the coal is dried to a moisture level of from about 9 to about 10%.
Claim 4
Dependent Claim
12 words
The process of claim 1 where the coal is a subbituminous coal.
Claim 5
Dependent Claim
11 words
The process of claim 3 where the coal is Wyodak coal.
Claim 6
Dependent Claim
10 words
The process of claim 1 where the coal is lignite.
References Cited (Backward Citations)
US3755912A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-28 | 1979-01-27 | 1979-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-28 | 1983-01-27 | 1983-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-28 | 1987-01-27 | 1987-07-29 | $7700.00 | Window Closed / Lapsed |