US3757861A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oil recovery employing peroxides and alkalis
Assignee: Dow Chemical Co
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Filing: 1971-04-01
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Granted: 1973-09-11
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Expires: 1991-04-01
Abstract
Abstract For more efficient recovery of petroleum, particularly for recovery of residual oil after conventional water flooding, an aqueous solution of hydrogen peroxide is injected into the oilbearing formation and followed by an alkaline solution such as an aqueous solution of sodium hydroxide. The resulting treated slug may then be displaced toward a production well or wells, preferably employing a mobility control agent in the driving fluid, to sweep out residual oil.
Inventors
- 👤 W Routson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 05:45
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/16; C; C09; C09K; C09K8/00; C09K8/58
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
29 words
A method according to claim 1 wherein the injected solutions are displaced through the formation from the injection well toward at least one producing well penetrating the same formation.
Claim 2
Dependent Claim
12 words
A method according to claim 1 wherein the peroxide is hydrogen peroxide.
Claim 3
Dependent Claim
20 words
A method according to claim 1 wherein the alkaline agent is ammonium hydroxide or an alkali metal hydroxide or carbonate.
Claim 4
Dependent Claim
13 words
A method according to claim 4 wherein the alkaline agent is sodium hydroxide.
Claim 5
Dependent Claim
46 words
A method according to claim 2 wherein the injected solutions consist, respectively, of an aqueous solution of from about 7 to about 15 percent by weight of hydrogen peroxide and an aqueous solution of from about 2 to about 5 percent by weight of sodium hydroxide.
Claim 6
Dependent Claim
23 words
A method according to claim 2 wherein the peroxide and alkaline solutions are displaced by injection of a solution of high-molecular-weight, water-soluble polymer.
Claim 7
Dependent Claim
29 words
A method according to claim 6 wherein the hydrogen peroxide solution is employed in the amount of from about 0.1 to about 0.5 pore volume of the treated formation.
Claim 8
Dependent Claim
33 words
A method according to claim 8 wherein the peroxide and sodium hydroxide solutions are followed by from about 0.05 to about 0.5 pore volume of an aqueous solution containing a high-molecular-weight, water-soluble polymer.
Claim 9
Dependent Claim
31 words
A method according to claim 9 wherein the polymer solution contains from about 100 to about 2,000 parts by weight of a partially hydrolyzed pOlyacrylamide per million parts of injected fluid.
Claim 10
Dependent Claim
31 words
A method according to claim 6 wherein the hydrogen peroxide solution is driven into the formation under pressure of an inert fluid prior to the injection of the sodium hydroxide solution.
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) | 1976-09-10 | 1977-03-12 | 1977-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-10 | 1981-03-12 | 1981-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-10 | 1985-03-12 | 1985-09-11 | $7700.00 | Window Closed / Lapsed |