US3556221A
Expired / Lapsed
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Well stimulation process
Assignee: Marathon Oil Co
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Filing: 1969-01-06
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Granted: 1971-01-19
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Expires: 1989-01-06
Abstract
Abstract Reduced permeabilities in the vicinity of a well bore caused by polymer solution deposits are improved by introducing into the well bore an aqueous solution having a pH greater than about 8 and containing sodium hypochlorite.
Inventors
- 👤 Gerald W Haws
- 👤 Joseph L Rael
- 👤 John S Rhudy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 17:01
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/84; C09K8/86; C09K8/88; C09K8/882
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
26 words
The process of claim 1 wherein the solution having a pH greater than 8 and less than about 13 comprises an alkali metal or ammonium hypochlorite.
Claim 2
Dependent Claim
22 words
The process of claim 1 wherein the solution having a pH greater than 8 and less than about 13 comprises sodium hypochlorite.
Claim 3
Dependent Claim
39 words
The process of claim 1 wherein injection of the solution having a pH greater than 8 and less than about 13 is followed by injecting an aqueous solution containing an acid having an ionization constant greater than about 10-5.
Claim 4
Dependent Claim
16 words
The process of claim 4 wherein the acid has an ionization constant greater than about 10-2.
Claim 5
Dependent Claim
16 words
The process of claim 1 wherein the polymer comprises a partially hydrolyzed high molecular weight polyacrylamide.
Claim 6
Dependent Claim
16 words
The process of claim 6 wherein the compound identified by the formula MOX is sodium hypochlorite.
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) | 1974-01-18 | 1974-07-20 | 1975-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-18 | 1978-07-20 | 1979-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-18 | 1982-07-20 | 1983-01-19 | $7700.00 | Window Closed / Lapsed |