Patent US3734180A successfully refreshed from Google Patents.
US3734180A
Expired / Lapsed
US
⏱️ 0.0 years remaining
In-situ gasification of coal utilizing nonhypersensitive explosives
Assignee: Cities Service Oil Co
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Filing: 1971-08-27
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Granted: 1973-05-22
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Expires: 1991-08-27
Abstract
Abstract Two or more wells are drilled into a coal seam. The wells are completed so as to isolate all other strata from the coal seam and a radially extended horizontal fracture is directed by introduction of a non-hypersensitive explosive under hydraulic fracturing conditions so as to connect the wells communitively. The explosive is ignited so that a horizontally and vertically directed fracture network is formed within the coal system. A combustion front is ignited and propagated through the fractured network to produce combustible gases and coal tar liquids.
Inventors
- 👤 V Rhoades
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:56
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; E21B43/24; E21B43/243; E21B43/247
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
34 words
The process of claim 1 further comprising the simultaneous injection of water with the combustion supporting gas so that a water-gas shift reaction is provided to increase the calorific content of the produced gas.
Claim 2
Dependent Claim
52 words
The process of claim 1 further comprising introducing a combustion supporting gas into at least one production well subsequent to the injection of the combustion supporting gas into the ignited wells to cause a reverse combustion and flow of injected gas, produced gas, and coal tar liquids to the previously ignited wells.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-21 | 1976-11-20 | 1977-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-21 | 1980-11-20 | 1981-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-21 | 1984-11-20 | 1985-05-22 | $7700.00 | Window Closed / Lapsed |