US3744566A
Expired / Lapsed
US
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Secondary oil recovery process
Assignee: Calgon Corp
•
Filing: 1972-03-16
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Granted: 1973-07-10
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Expires: 1992-03-16
Abstract
Abstract Polymers of (3-acrylamido-3-methyl) butyl trimethyl ammonium chloride and related N-(alkyl amino) acrylamides are used as additives to water for waterflooding in the secondary recovery of oil.
Inventors
- 👤 M Szabo
- 👤 F Martin
- 👤 J Boothe
- 👤 A Sharpe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:59
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/58; C09K8/588; Y; Y10; Y10S; Y10S507/00; Y10S507/935; Y10S507/936
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
16 words
Method of claim 1 in which the polymer has a molecular weight of at least 100,000.
Claim 2
Dependent Claim
15 words
Method of claim 1 in which the cationic monomer is (3-acrylamido-3-methyl) butyl trimethyl ammonium chloride.
Claim 3
Dependent Claim
20 words
Method of claim 1 in which the polymer is a copolymer including about 10 to about 99 mole percent acrylamide.
Claim 4
Dependent Claim
29 words
Method of claim 1 in which the polymer is a copolymer of about 60 to about 90 mole percent acrylamide and the balance is (3-acrylamido-3-methyl) butyl trimethyl ammonium chloride.
Claim 5
Dependent Claim
20 words
Method of claim 1 in which the aqueous flooding medium is a brine of at least 2 percent dissolved solids.
Claim 6
Dependent Claim
58 words
A secondary oil recovery process comprising forming a flooding medium of an aqueous solution of from 20 to 6,500 ppm water-soluble polymer of (3-acrylamido-3-methyl) butyl trimethyl ammonium chloride, injecting the flooding medium into an injection well penetrating a subterranean oil-bearing formation, and forcing the flooding medium through said formation towards at least one producing well in said formation.
Claim 7
Dependent Claim
57 words
In a method of recovering oil from an underground formation in which an aqueous flooding medium is forced from an injection well toward a producing well to displace the oil in said formation, the improvement comprising adding to said aqueous flooding medium a water-soluble polymer including at least 1 percent by weight cationic monomers of the formula
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) | 1976-07-09 | 1977-01-08 | 1977-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-09 | 1981-01-08 | 1981-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-09 | 1985-01-08 | 1985-07-10 | $7700.00 | Window Closed / Lapsed |