US3792731A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Secondary recovery process using surfactant mixtures
Assignee: Texaco Inc
•
Filing: 1972-05-08
•
Granted: 1974-02-19
•
Expires: 1992-05-08
Abstract
Abstract Improved recovery in a waterflood process is effected by the use of a saline, aqueous slug containing a mixture of a nonionic and an anionic surfactant, followed by a drive agent such as water, brine or thickened water or brine.
Inventors
- 👤 D Feuerbacher
- 👤 G Homolka
- 👤 G Alves
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:09
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/58; C09K8/584; E; E21; E21B; E21B43/00; E21B43/16; E21B43/20; Y; Y10; Y10S; Y10S507/00; Y10S507/935; Y10S507/936
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
23 words
The method of claim 1 wherein said slug is injected in amounts from about 0.05 to about 0.5 of the reservoir pore volume.
Claim 2
Dependent Claim
37 words
The method of claim 1 wherein said mixture contains from about 20 percent to about 50 percent by weight of said nonionic surfactant, and about 80 percent to about 50 percent by weight of said anionic surfactant.
Claim 3
Dependent Claim
22 words
The method of claim 1 wherein said saline slug contains about 0.5 percent to about 15.0 percent of an alkali metal halide.
Claim 4
Dependent Claim
13 words
The method of claim 4 wherein said alkali metal halide is sodium chloride.
Claim 5
Dependent Claim
24 words
The method of claim 1 wherein said slug contains a thickening agent in amounts from about 0.01 percent to about 0.5 percent by weight.
Claim 6
Dependent Claim
19 words
The method of claim 1 wherein said driving fluid is water, brine, thickened water, thickened brine and mixtures thereof.
Claim 7
Dependent Claim
97 words
In a waterflood process for recovering residual oil from a subterranean oil-bearing reservoir where-in an aqueous driving agent is injected into at least one injection well, and oil is thereby displaced through the reservoir and recovered at at least one production well, the improvement comprising injecting via said injection well and prior to the injection of said aqueous driving agent, an aqueous saline slug containing a mixture of a nonionic surfactant and an anionic surfactant, said surfactant mixture being present in said slug in a concentration of from about 0.5 percent to about 2.5 percent by weight.
Claim 8
Dependent Claim
23 words
The method of claim 8 wherein said slug is injected in amounts from about 0.05 to about 0.5 of the reservoir pore volume.
Claim 9
Dependent Claim
37 words
The method of claim 8 wherein said mixture contains from about 20 percent to about 50 percent by weight of said nonionic surfactant, and about 80 percent to about 50 percent by weight of said anionic surfactant.
Claim 10
Dependent Claim
22 words
The method of claim 8 wherein said saline slug contains about 0.5 percent to about 15.0 percent of an alkali metal halide.
Claim 11
Dependent Claim
13 words
The method of claim 11 wherein said alkali metal halide is sodium chloride.
Claim 12
Dependent Claim
24 words
The method of claim 8 wherein said slug contains a thickening agenT in amounts from about 0.01 percent to about 0.5 percent by weight.
Claim 13
Dependent Claim
19 words
The method of claim 8 wherein said driving fluid is water, brine, thickened water, thickened brine and mixtures thereof.
References Cited (Backward Citations)
US3096820A
Cited
US3348611A
Cited
US3369602A
Cited
US3446282A
Cited
US3467190A
Cited
US3468377A
Cited
US3498379A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-18 | 1977-08-20 | 1978-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-18 | 1981-08-20 | 1982-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-18 | 1985-08-20 | 1986-02-19 | $7700.00 | Window Closed / Lapsed |