US4410042A
Expired / Lapsed
US
⏱️ 0.0 years remaining
In-situ combustion method for recovery of heavy oil utilizing oxygen and carbon dioxide as initial oxidant
Assignee: Mobil Oil AS
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Filing: 1981-11-02
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Granted: 1983-10-18
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Expires: 2001-11-02
Abstract
Abstract An in-situ combustion method for recovering viscous oil from a subterranean, viscous oil-containing formation comprising injecting a mixture of essentially pure oxygen and carbon dioxide into the formation to initiate an in-situ combustion operation followed by injecting essentially pure oxygen.
Inventors
- 👤 Winston R. Shu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 03:53
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; E21B43/24; E21B43/243
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
130 words
A method for recovering oil from a subterranean, viscous oil-containing formation penetrated by at least one injection well and a spaced apart production well comprising: (a) initiating an in-situ combustion front in the formation by injecting a combustion-supporting gas comprising a mixture of essentially pure oxygen and carbon dioxide into the injection well and continuing injection of said combustion-supporting gas until said combustion front has advanced a predetermined distance from the injection well, said injected carbon dioxide dissolving in the in place oil thereby reducing its viscosity and increasing effective oil permeability; (b) thereafter terminating injection of the mixture of essentially pure oxygen and carbon dioxide and injecting essentially pure oxygen into the injection well to support in-situ combustion; and (c) producing oil from the formation via said production well.
Claim 2
Independent Claim
130 words
A method for recovering oil from a subterranean, viscous oil-containing formation penetrated by at least one injection well and a spaced apart production well comprising: (a) initiating an in-situ combustion front in the formation by injecting a combustion-supporting gas comprising a mixture of essentially pure oxygen and carbon dioxide into the injection well and continuing injection of said combustion-supporting gas until said combustion front has advanced a predetermined distance from the injection well, said injected carbon dioxide dissolving in the in place oil thereby reducing its viscosity and increasing effective oil permeability; (b) thereafter terminating injection of the mixture of essentially pure oxygen and carbon dioxide and injecting essentially pure oxygen into the injection well to support in-situ combustion; and (c) producing oil from the formation via said production well.
Claim 3
Dependent Claim
19 words
The method of claim 1 wherein the combustion-supporting gas in step (a) comprises not more than 80% carbon dioxide.
Claim 4
Dependent Claim
40 words
The method of claim 1 wherein injection of the mixture of essentially pure oxygen and carbon dioxide is continued during step (a) until the combustion front has advanced away from the injection well a distance of at least 30 feet.
Claim 5
Dependent Claim
29 words
The method of claim 1 further comprising gradually decreasing the amount of carbon dioxide in said combustion-supporting gas following step (a) until the gas injected comprises essentially pure oxygen.
Claim 6
Dependent Claim
32 words
The method of claim 4 wherein the amount of carbon dioxide is gradually decreased when the combustion front has advanced away from the injection well a distance of at least 30 feet.
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) | 1986-10-17 | 1987-04-18 | 1987-10-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-17 | 1991-04-18 | 1991-10-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-17 | 1995-04-18 | 1995-10-18 | $7700.00 | Window Closed / Lapsed |