Patent US3687199A successfully refreshed from Google Patents.
US3687199A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the secondary recovery of petroleum
Assignee: Dow Chemical Co
•
Filing: 1970-05-07
•
Granted: 1972-08-29
•
Expires: 1990-05-07
Abstract
Abstract Crude oil is recovered from a subterranean oil bearing formation by injecting an initial slug of an aqueous flooding medium containing a dissolved polymeric agent into the formation to displace the oil toward at least one output well communicating with the formation and then following the initial slug with a secondary aqueous slug having a dissolved polymer concentration of less than about one-third that of the initial slug but not in excess of 100 p.p.m.
Inventors
- 👤 Robert R Jennings
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:57
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/58; C09K8/588
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
17 words
The process of claim 1 wherein the secondary slug contains the same polymer as the first slug.
Claim 2
Dependent Claim
29 words
The process of claim 1 wherein the viscosity of the initial slug is greater than about one-half of 1 percent of the viscosity of the oil to be displaced.
Claim 3
Dependent Claim
21 words
The process of claim 1 wherein the concentration of the secondary slug is one-fourth to one-tenth that of the initial slug.
Claim 4
Dependent Claim
29 words
The process of claim 1 wherein the mobility factor of the secondary polymer bank is at least twice the mobility factor of the brine or water after polymer treatment.
Claim 5
Dependent Claim
12 words
The process of claim 1 wherein the dissolved polymer is a polyacrylamide.
Claim 6
Dependent Claim
11 words
The process of claim 6 wherein the polyacrylamide is partially hydrolyzed.
References Cited (Backward Citations)
US2827964A
Cited
US3018826A
Cited
US3039529A
Cited
US3370649A
Cited
US3406754A
Cited
US3467187A
Cited
US3434542A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-29 | 1976-02-28 | 1976-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-29 | 1980-02-28 | 1980-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-29 | 1984-02-28 | 1984-08-29 | $7700.00 | Window Closed / Lapsed |