Patent US3721295A successfully refreshed from Google Patents.
US3721295A
Expired / Lapsed
US
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Secondary recovery of petroleum
Assignee: ChampionX LLC
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Filing: 1971-11-23
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Granted: 1973-03-20
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Expires: 1991-11-23
Abstract
Abstract This invention relates to the secondary recovery of petroleum, and in particular, involves a process for reducing the amount of water recovered from a producing well in a water flooding process for recovering petroleum from a subterranean oil-bearing formation. This reduction in water is accomplished by introducing a water-in-oil emulsion which contains dispersed therein from 0.01 to 35 percent by weight of a finely-divided water-soluble vinyl addition polymer.
Inventors
- 👤 L Bott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:56
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/58; C09K8/584; C09K8/588
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
66 words
The process of claim 1 wherein the water-in-oil emulsion is comprised of: A. water ranging between 0.01 and 25 percent by weight; B. a water-soluble vinyl addition polymer having a concentration between 0.1 and 35 percent by weight; C. a hydrophobic liquid ranging between 5 and 99 percent by weight; and D. a water-in-oil emulsifying agent having a concentration between 0.001 and 30 percent by weight.
Claim 2
Dependent Claim
66 words
The process of claim 1 wherein the water-in-oil emulsion is comprised of: A. water ranging between 5 and 25 percent by weight; B. a water-soluble vinyl addition polymer having a concentration between 20 and 50 percent by weight; C. a hydrophobic liquid ranging between 5 and 35 percent by weight; and D. a water-in-oil emulsifying agent having a concentration between 0.1 and 30 percent by weight.
Claim 3
Dependent Claim
26 words
The process of claim 1 wherein the concentration of the water-soluble vinyl addition polymer in the polymeric latex is from 0.1 to 10 percent by weight.
Claim 4
Dependent Claim
13 words
The process of claim 1 wherein the pOlymer is an acrylamide-sodium acrylate copolymer.
Claim 5
Dependent Claim
16 words
The process of claim 5 wherein the weight ratio of acrylamide to sodium acrylate is 65:35.
Claim 6
Dependent Claim
10 words
The process of claim 1 wherein the polymer is polyacrylamide.
Claim 7
Dependent Claim
13 words
The process of claim 1 wherein the polymer is an acrylamide-methacrylic acid copolymer.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-19 | 1976-09-18 | 1977-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-19 | 1980-09-18 | 1981-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-19 | 1984-09-18 | 1985-03-20 | $7700.00 | Window Closed / Lapsed |