US4243511A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for suppressing carbonate decomposition in vapor phase water retorting
Assignee: Marathon Oil Co
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Filing: 1979-03-26
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Granted: 1981-01-06
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Expires: 1999-03-26
Abstract
Abstract Oil shale containing relatively large quantities of alkaline carbonate minerals is retorted utilizing superheated water vapor at temperatures of from about 425° C. to about 510° C. Retorting with a sufficient carbon dioxide partial pressure effectively suppresses decomposition of the alkaline carbonates to obtain an environmentally acceptable retorted shale.
Inventors
- 👤 Victor D. Allred
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 00:02
CPC Classifications
C; C10; C10G; C10G1/00; C10G1/02; Y; Y10; Y10S; Y10S208/00; Y10S208/951
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
138 words
In a process for the recovery of organic values from oil shale containing alkaline metal carbonates by contacting said oil shale with superheated water vapor in a retort wherein the recovery of said hydrocarbon values is enhanced by contacting particles of said oil shale with said superheated water vapor at a superficial gas velocity of at least 10 cm per second and at a pressure in the range of from about 6.9 to about 1,034 kPaa and by providing said contact with said superheated water vapor at a temperature of from about 425° C. to about 510° C. to produce an effluent stream comprising superheated water vapor, hydrocarbon vapors, hydrogen, and carbon oxides, the improvement comprising: providing a carbon dioxide partial pressure during said contacting which is sufficient to effectively suppress thermal decomposition of said carbonates to oxides.
Claim 2
Dependent Claim
138 words
In a process for the recovery of organic values from oil shale containing alkaline metal carbonates by contacting said oil shale with superheated water vapor in a retort wherein the recovery of said hydrocarbon values is enhanced by contacting particles of said oil shale with said superheated water vapor at a superficial gas velocity of at least 10 cm per second and at a pressure in the range of from about 6.9 to about 1,034 kPaa and by providing said contact with said superheated water vapor at a temperature of from about 425° C. to about 510° C. to produce an effluent stream comprising superheated water vapor, hydrocarbon vapors, hydrogen, and carbon oxides, the improvement comprising: providing a carbon dioxide partial pressure during said contacting which is sufficient to effectively suppress thermal decomposition of said carbonates to oxides.
Claim 3
Dependent Claim
30 words
The process of claim 1 wherein said carbon dioxide partial pressure is provided by separating carbon dioxide from said effluent stream and introducing said separated carbon dioxide into said retort.
Claim 4
Dependent Claim
49 words
The process of claim 2 wherein said separated carbon dioxide is introduced into said retort at locations adjacent to the top and the bottom of said retort so as to minimize leakage to retort product gases from the retort and to uniformly distribute said carbon dioxide throughout said retort.
Claim 5
Dependent Claim
18 words
The process of claim 1 wherein the superheated water vapor is about 450° C. to about 480° C.
Claim 6
Dependent Claim
18 words
The process of claim 1 wherein the superheated water vapor is about 450° C. to about 470° C.
Claim 7
Dependent Claim
15 words
The process of claim 1 wherein the pressure is about 13.8 to about 689 kPaa.
Claim 8
Dependent Claim
19 words
The process of claim 1 wherein the superficial gas velocity is about 10 to about 305 cm per second.
References Cited (Backward Citations)
US3480082A
Cited
US3960702A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-01-06 | 1984-07-07 | 1985-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-06 | 1988-07-07 | 1989-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-06 | 1992-07-07 | 1993-01-06 | $7700.00 | Window Closed / Lapsed |