Patent US3964545A successfully refreshed from Google Patents.
US3964545A
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Processes for secondarily recovering oil
Assignee: Esorco Corp
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Filing: 1974-06-10
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Granted: 1976-06-22
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Expires: 1994-06-10
Abstract
Abstract A secondary recovery process using injected air to pressurize the formation and maintain mobility of the reservoir oil by diluting the oil with carbon dioxide. Carbon dioxide is produced as a by-product of air injection, either by auto-oxidation of carbonaceous materials in the reservoir rock, or by ignition of oil in the reservoir. Efficiency of oxidation is observed by testing O 2 content of the effluent gas; it is desirable to hold the oxygen content in the effluent gas to less than 3% by volume in the effluent gas. When this content cannot be reached by auto-oxidation, it is necessary to ignite the oil.
Inventors
- 👤 Frank N. Speller, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:41
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; E21B43/24; E21B43/243
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
150 words
The method of secondary recovery of oil from a reservoir including the steps of injecting air in a reservoir at a point spaced from a production well, maintaining the volume and pressure of the injected air so that a reservoir pressure of at least 500 p.s.i.g. is maintained, causing oxidation of reservoir material which results in the production of an effluent gas containing oxygen and carbon dioxide, reducing the surface tension of said oil in the reservoir by dissolving the carbon dioxide in the reservoir oil to render the high-gravity, paraffin-base oils more mobile and susceptible of being driven to the production well, keeping the dissolved carbon dioxide in the oil by maintaining said pressure and volume of the injected air, controlling the oxygen content of said effluent gas to a level of less than three percent by volume, withdrawing said effluent gas and oil separately from the production well.
Claim 2
Independent Claim
150 words
The method of secondary recovery of oil from a reservoir including the steps of injecting air in a reservoir at a point spaced from a production well, maintaining the volume and pressure of the injected air so that a reservoir pressure of at least 500 p.s.i.g. is maintained, causing oxidation of reservoir material which results in the production of an effluent gas containing oxygen and carbon dioxide, reducing the surface tension of said oil in the reservoir by dissolving the carbon dioxide in the reservoir oil to render the high-gravity, paraffin-base oils more mobile and susceptible of being driven to the production well, keeping the dissolved carbon dioxide in the oil by maintaining said pressure and volume of the injected air, controlling the oxygen content of said effluent gas to a level of less than three percent by volume, withdrawing said effluent gas and oil separately from the production well.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein the effluent gas is produced by auto-oxidation.
Claim 4
Dependent Claim
25 words
The method of claim 1 wherein the percent volume of oxygen in the effluent gas is controlled through control of volume of the injected air.
Claim 5
Dependent Claim
55 words
The method of claim 1 wherein said carbon dioxide is also produced by ignition and combustion of the reservoir adjacent to the point of air injection whenever auto-oxidation of the oil in the reservoir is insufficient to maintain the oxygen content of the effluent gas to a level of less than three percent by volume.
Claim 6
Dependent Claim
14 words
The method of claim 1 wherein said effluent gas is recycled through the reservoir.
References Cited (Backward Citations)
US2630307A
Cited
US2642943A
Cited
US2718263A
Cited
US2818117A
Cited
US2771951A
Cited
US3019837A
Cited
US3032102A
Cited
US3072185A
Cited
US3174543A
Cited
US3209825A
Cited
US3205944A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-22 | 1979-12-22 | 1980-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-22 | 1983-12-22 | 1984-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-22 | 1987-12-22 | 1988-06-22 | $7700.00 | Window Closed / Lapsed |