US3653440A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Secondary and tertiary oil recovery process
Assignee: Shell USA Inc
•
Filing: 1970-03-23
•
Granted: 1972-04-04
•
Expires: 1990-03-23
Abstract
Abstract A waterflood process for producing oil from an underground reservoir is improved by injecting an oil-displacing surfactant system, a gas, and an aqueous drive liquid so that, within the reservoir, the relative permeability of liquid that is injected and displaced is reduced by the gas.
Inventors
- 👤 Joseph Reisberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:17
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/58; C09K8/584
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
31 words
The process of claim 1 wherein the surfactant is an organic sulfonate and the injected gas is selected from the group consisting of air, nitrogen, CO2, flue gases, and gaseous hydrocarbons.
Claim 2
Dependent Claim
22 words
The process of claim 2 wherein the active surfactant system is an aqueous solution containing an organic sulfonate and an organic sulfate.
Claim 3
Dependent Claim
12 words
The process of claim 3 wherein the aqueous drive liquid is saline.
Claim 4
Dependent Claim
33 words
The process of claim 4 wherein the total volume of injected active surfactant system is from about 5 to 30 percent of the pore volume of the swept zone of the reservoir formation.
Claim 5
Dependent Claim
33 words
The process of claim 5 wherein the active surfactant system is an aqueous dispersion containing an organic sulfonate, the injected gas is nitrogen, and the injected aqueous drive liquid contains an organic sulfonate.
Claim 6
Dependent Claim
24 words
The process of claim 1 wherein the active surfactant system is an aqueous solution containing an organic sulfonate and the injected gas is nitrogen.
Claim 7
Dependent Claim
27 words
The process of claim 1 wherein an injection of most of the active surfactant system precedes a substantially simultaneous injection of the gas and aqueous drive liquid.
Claim 8
Dependent Claim
49 words
The process of claim 1 wherein an injection of at least the bulk of the active surfactant system precedes an injection of alternating slugs of the gas and the aqueous drive liquid, with each of said slugs amounting to about 10% of the pore volume of the swept zone.
References Cited (Backward Citations)
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Cited
US3330346A
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US3302713A
Cited
US3254714A
Cited
US3474864A
Cited
US3529668A
Cited
US3508612A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-04 | 1975-10-04 | 1976-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-04 | 1979-10-04 | 1980-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-04 | 1983-10-04 | 1984-04-04 | $7700.00 | Window Closed / Lapsed |