US3599716A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for secondary oil recovery
Assignee: Atlantic Richfield Co
•
Filing: 1969-04-09
•
Granted: 1971-08-17
•
Expires: 1989-04-09
Abstract
Abstract A secondary oil recovery method which comprises successively injecting into a subterranean oil-bearing formation air and water, e.g. as alternate slugs. The water has dissolved therein a surfactant and an acid or base to increase the efficiency of the surfactant.
Inventors
- 👤 James L Thompson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:40
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/58; C09K8/584
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
20 words
The method of claim 1 wherein the adsorption is less than 30 X 10 6 grams per gram formation sand.
Claim 2
Dependent Claim
21 words
The method of claim 1 wherein the surfactant is added to the solution in amounts of less than 5 wt. percent.
Claim 3
Dependent Claim
38 words
The method of claim 3 wherein the surfactant-containing water solution includes an alkaline material selected from the group consisting of sodium hydroxide, potassium hydroxide and ammonium hydroxide in an amount of from about 0.1 to 25 wt. percent.
Claim 4
Dependent Claim
90 words
The method of claim 1 wherein the surfactant-containing solution is injected into the formation in an amount of from about 0.5 percent to 50 percent of the pore volume of the formation to form an intermediate slug and further including injecting additional oxygen-containing gas into the formation to produce a second slug thereof behind said intermediate slug and thereafter injecting additional solution into said formation from the input well to push the second air slug, the intermediate slug and the first-formed air slug through said formation to the output well.
Claim 5
Independent Claim
182 words
A method for secondary recovery of crude oil from a subterranean oil-bearing formation which comprises injecting into the formation from an input well firstly an oxygen-containing gas in an amount sufficient to produce a slug thereof in the formation pushing ahead the crude oil and sufficient to produce in-situ surface active components in the crude oil and thereafter injecting a surfactant-containing aqueous caustic solution into the formation from said input well in an amount sufficient to push the gas slug through the formation and to drive the crude oil through the formation to an output well, said solution having dissolved therein a water-soluble polyoxyalkylene phosphate ester surfactant or a metal salt thereof, of the general type R-OPO3H2 and (R-O)2 PO2H in an amount sufficient to reduce the interfacial tension between the solution and crude oil to below 1 dyne/cm. and also an alkaline material in an amount sufficient to increase the efficiency of the surfactant in the solution, said amount of alkaline material being between 0.1 and 25 wt. percent of the solution, and thereafter recovering crude oil at the output well.
Claim 6
Dependent Claim
37 words
The method of claim 6 wherein the gas is injected in an amount sufficient to ensure that the adsorption of the surfactant on the formation is less than 100 X 10 6 grams per gram formation sand.
Claim 7
Dependent Claim
20 words
The method of claim 7 wherein the adsorption is less than 30 X 10 6 grams per gram formation sand.
Claim 8
Dependent Claim
30 words
The method of claim 6 wherein said gas is air and the amount of air injected is from about 0.5 to 50 percent of the pore volume of the formation.
Claim 9
Dependent Claim
21 words
The method of claim 9 wherein the surfactant is added to the solution in amounts of less than 5 wt. percent.
Claim 10
Dependent Claim
89 words
The method of claim 10 wherein the surfactant-containing solution is injected into the formation in an amount of from about 0.5 to 50 percent of the pore volume of the fOrmation to form an intermediate slug and further including injecting additional oxygen-containing gas into the formation to produce a second slug thereof behind said intermediate slug and thereafter injecting additional solution into said formation from the input well to push the second air slug, the intermediate slug and the first-formed air slug through said formation to the output well.
Claim 11
Dependent Claim
191 words
In a method for recovery of crude oil from a subterranean oil-bearing formation, the steps which comprise successively injecting into the formation from an input well firstly an oxygen-containing gas in an amount sufficient to produce a slug thereof in the formation pushing ahead the crude oil and sufficient to produce in-situ surface active components in the crude oil, thereafter injecting surfactant-containing water solution into the formation from said input well in an amount from about 0.5 to 50 percent of the pore volume of the formation to form an intermediate slug, said water solution having dissolved therein a water-soluble surfactant which is compatible with the crude oil and reduces interfacial tensions between the water and crude oil to below 1 dyne/cm. when added to the water in amounts less than 1 wt. percent, injecting additional oxygen-containing gas into the formation to produce a second slug thereof behind said intermediate slug and thereafter injecting additional solution into said formation from the input well to push the second air slug, the intermediate slug and the first-formed air slug through said formation to the output well, and recovering oil from the output well.
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) | 1974-08-16 | 1975-02-15 | 1975-08-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-16 | 1979-02-15 | 1979-08-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-16 | 1983-02-15 | 1983-08-17 | $7700.00 | Window Closed / Lapsed |