Patent US3617466A successfully refreshed from Google Patents.
US3617466A
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Gas combustion retort process
Assignee: Atlantic Richfield Co
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Filing: 1968-12-06
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Granted: 1971-11-02
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Expires: 1988-12-06
Abstract
Abstract An improved method for obtaining oil from oil shale by the gas combustion retort process. The offgas from the retort containing oil, fuel and other combustion products is treated first to remove the oil and second, to burn the fuel components. The resulting gas is recycled into the retort to pass countercurrently to the shale travel. Temperatures in the combustion zone of the retort are moderated and clinker formation is eliminated. The heat from the fuel burning can be used as a power source.
Inventors
- 👤 John C Todd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:09
CPC Classifications
C; C10; C10G; C10G1/00; C10G1/02
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
11 words
The method of claim 1 wherein the oxidant gas is air.
Claim 2
Dependent Claim
25 words
The method of claim 1 wherein part of the resulting flue gas is also mixed with the oxidant gas prior to introduction in the retort.
Claim 3
Dependent Claim
48 words
The method of claim 1 wherein the preheat zone is at a temperature of 60*-750* F., the retorting zone is at a temperature of 750*-1,200* F., the combustion zone is at a temperature of 1,200*-1,800* F., and the heat recovery zone is at a temperature of 1,800*-2,000* F.
Claim 4
Dependent Claim
15 words
The method of claim 1 wherein the spent shale contains 1 to 5 percent carbon.
Claim 5
Dependent Claim
162 words
In the process for retorting oil shale by the gas combustion retort process in which oil shale is intrOduced into a retort and passed through a preheat zone, a retort zone, a combustion zone wherein at least some carbon content in the spent shale from the retort zone is burned with an oxidant gas and a heat recovery zone and the offgas is withdrawn from the retort and recycled after the oil is removed from it back into the heat recovery zone of the retort to travel countercurrently to the flow of the shale, the improvement which moderates the temperature of the combustion zone and avoids clinker formation which comprises removing fuel from the offgas after the oil is removed and prior to its recycling into the retort and recycling at least part of the gas resulting from removal of the fuel from the offgas into the retort through the combustion zone during combustion of the spent shale in the combustion zone.
Claim 6
Dependent Claim
18 words
The improvement of claim 6 wherein the fuel removal is by burning the oil-depleted offgas in a boiler.
Claim 7
Dependent Claim
18 words
The improvement of claim 6 wherein the spent shale has a carbon content of 1 to 5 percent.
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) | 1974-11-01 | 1975-05-03 | 1975-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-01 | 1979-05-03 | 1979-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-01 | 1983-05-03 | 1983-11-02 | $7700.00 | Window Closed / Lapsed |