US3770398A
Expired / Lapsed
US
⏱️ 0.0 years remaining
In situ coal gasification process
Assignee: Cities Service Oil Co
•
Filing: 1971-09-17
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Granted: 1973-11-06
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Expires: 1991-09-17
Abstract
Abstract A method for in situ coal gasification to recover a calorific value gas by the water-gas shift reaction for the optimum formation of carbon monoxide and hydrogen through the simultaneous introduction of carbon dioxide and steam into an injection well in order to shift the reaction kinetics of the process to favor the water-gas shift reaction.
Inventors
- 👤 G Abraham
- 👤 C Royo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:21
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; E21B43/24; E21B43/243; E21B43/247; E21B43/34; E21B43/40; Y; Y10; Y10S; Y10S48/00; Y10S48/06
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
22 words
The process of claim 1 further comprising reinitiating combustion of the coal deposit when the temperature therein becomes less than about 1,000*C.
Claim 2
Dependent Claim
20 words
The process of claim 1 wherein the carbon dioxide introduced is obtained from the produced gas from the coal deposit.
Claim 3
Dependent Claim
17 words
The process of claim 3 wherein the carbon dioxide is removed from the produced gas by absorption.
Claim 4
Dependent Claim
31 words
The process of claim 3 further comprising subjecting the steam introduced to contact with the produced gas from the coal deposit to regain the waste heat contained in the produced gas.
Claim 5
Dependent Claim
78 words
In a process for the in situ recovery of a synthetic gas having a high calorific energy value, from a subterranean coal deposit wherein a combustion supporting gas and steam are simultaneously injected into the coal deposit to maintain the temperature therein above about 1,000*C and to produce a water-gas by the water-gas shift reaction, the improvement comprising simultaneously introducing carbon dioxide into the coal deposit in order to favor the reaction kinetics of the water-gas shift reaction.
Claim 6
Dependent Claim
17 words
The process of claim 6 wherein the carbon dioxide is removed from the produced gas by absorption.
Claim 7
Dependent Claim
31 words
The process of claim 6 further comprising subjecting the steam introduced to contact with the produced gas from the coal deposit to regain the waste heat contained in the produced gas.
References Cited (Backward Citations)
US3506309A
Cited
US3628929A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-05 | 1977-05-07 | 1977-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-05 | 1981-05-07 | 1981-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-05 | 1985-05-07 | 1985-11-06 | $7700.00 | Window Closed / Lapsed |