US4100966A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oil recovery process using an emulsion slug with tapered surfactant concentration
Assignee: Texaco Inc
•
Filing: 1976-09-20
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Granted: 1978-07-18
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Expires: 1996-09-20
Abstract
Abstract A process for recovering oil from a subterranean reservoir in which a slug comprising a hydrocarbon-in-water emulsion together with a small amount of surfactant injected into the formation via an injection well is forced through the formation and oil is recovered via a production well penetrating the formation. In this process an emulsion slug is employed in which the surfactant concentration is tapered by increasing the concentration of the surfactant either incrementally, gradually or by any other convenient method during the slug injection time.
Inventors
- 👤 Issam S. Bousaid
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:02
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/58; C09K8/584; C09K8/588; Y; Y10; Y10S; Y10S507/00; Y10S507/935; Y10S507/936
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
92 words
A method of recovering oil from a subterranean oil-bearing formation having in communication therewith at least one injection well and at least one production well comprising: (a) injecting into the formation via the injection well a slug comprising a hydrocarbon-in-water emulsion containing a small amount of a surfactant, (b) injecting water into the formation via the injection well; and (c) recovering oil from the formation via the said production well and wherein the concentration of the surfactant in the said slug is increased as the slug is injected into the said formation.
Claim 2
Independent Claim
92 words
A method of recovering oil from a subterranean oil-bearing formation having in communication therewith at least one injection well and at least one production well comprising: (a) injecting into the formation via the injection well a slug comprising a hydrocarbon-in-water emulsion containing a small amount of a surfactant, (b) injecting water into the formation via the injection well; and (c) recovering oil from the formation via the said production well and wherein the concentration of the surfactant in the said slug is increased as the slug is injected into the said formation.
Claim 3
Dependent Claim
24 words
The method of claim 1 wherein prior to step (a) a preflush slug of water is injected into the formation via the injection well.
Claim 4
Dependent Claim
27 words
The method of claim 1 wherein the concentration of the surfactant in the said slug is incrementally increased as the slug is injected into the said formation.
Claim 5
Dependent Claim
26 words
The method of claim 1 wherein the concentration of the surfactant in the said slug is continuously increased as the slug is injected into the formation.
Claim 6
Dependent Claim
24 words
The method of claim 1 wherein prior to step (b) there is introduced into the said formation a slug of an aqueous polymer solution.
Claim 7
Dependent Claim
23 words
The method of claim 5 wherein the said polymer is selected from the group consisting of polyacrylamide, partially hydrolyzed polyacrylamide, and a polysaccharide.
Claim 8
Dependent Claim
13 words
The method of claim 1 wherein the step (b) saline water is injected.
Claim 9
Dependent Claim
228 words
The method of claim 1 wherein the water injected in step (b) contains a small amount of a solubilizing agent selected from the group consisting of: (a) a compound of the formula: ##STR10## wherein R is alkyl of from 1 to about 16 carbon atoms; wherein R' is alkylene of from 2 to 4 inclusive carbon atoms; m is an integer of from 8 to about 60; A is selected from the group consisting of hydrogen, sodium, potassium and the ammonium ion and wherein R" is selected from the group consisting of hydrogen, alkyl of from 1 to about 16 carbon atoms and R'O(CH 2 CH 2 O) m A; (b) a sulfated compound of the formula: ##STR11## wherein R, R', m and A have the same meaning as in (a) above, and R" is selected from the group consisting of hydrogen, alkyl of from 1 to about 16 carbon atoms and R'O(CH 2 CH 2 O) m SO 3 A, and (c) a sulfonated compound of the formula: ##STR12## wherein R, R' and A have the same meaning as in (a) above; wherein n is an integer of from about 8 to about 60 and R" is selected from the group consisting of hydrogen, alkyl of from 1 to about 16 carbon atoms and R'O(CH 2 CH 2 O) n CH 2 CH 2 SO 3 A.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-07-17 | 1982-01-16 | 1982-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-17 | 1986-01-16 | 1986-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-17 | 1990-01-16 | 1990-07-18 | $7700.00 | Window Closed / Lapsed |