US3908764A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of treating petroleum-bearing formations for supplemental oil recovery
Assignee: Phillips Petroleum Co
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Filing: 1974-11-25
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Granted: 1975-09-30
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Expires: 1994-11-25
Abstract
Abstract A polymer treatment method is used to improve mobility control in flooding a petroleum-bearing subterranean formation containing petroleum and connate water. Mobility is controlled by injection into the formation of a slug of an aqueous polymer mixture which has a viscosity sensitive to the salt concentration in the water mixed with same to form the slug. The polymer slug is injected into the formation and is followed with a slug of high-brine concentration water which is then followed with a second slug of water having a lower brine concentration than the first slug to control the mobility in the petroleum-bearing formation. Drive fluid is then injected into the formation to drive the petroleum therein to a well for removal and use.
Inventors
- 👤 Robert R Harvey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:33
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/58; C09K8/588; E; E21; E21B; E21B43/00; E21B43/16; E21B43/20
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
169 words
A METHOD OF TREATING PERTOLEUM-BEARING FORMATION WITH AN AQUEOUS SOLUTION OF SALT-SENSITIVE POLYMER TO CONTROL MOBILITY THE FORMATION FOR SECONDARY AND TERIARY RECOVERY, SAID METHOD COMPRISING, A, SELECTING AS SAID SALT-SENSETIVE POLYMER, COMPOUNDS OF WHICH THEVISCOSITY IS DECREASED BY INCREASING THE INORGANIC SALT CONCENTRATION IN AQUEOUS SOLUTION CONTAINING SUCH SALT-SENSETIVE POLYMERS, B. FORMING AN AQUEOUS MIXTURE OF SAID SALT-SENSITIVE POLYMER AND INORGANIC SALT TO FORM A HIGH BRIME CONCENTRATION MIXTURE C. INJECTING A FIRST INJECTION OF SAID BRIME MIXTURE INTO A PETROLEUM-BEARING FORMATION CONTANING HIGH BRIME WATER THEREIN, D. FOLLOWING THE INJECTION OF SAID HIGH BRIME MIXTURE WITH A SECOND INJECTION OF A HIGH BRIME AQUEOUS SOLUTION, E. FOLLOWING THE SECOND INJECTION WITH A THIRD INJECTION OF AN AQUEOUS BRIME SOLUTION WEAKER THAN SAID HIGH BRIME MIXTURE AND HIGH BRIME AQUEOUS SOLUTION THEREBY DECREASING THE SALT CONCENTRATION IN THE PETROLEUM-BEARING FORMATION BY ADMIXING WITH THE FIRST AND SECOND INJECTIONS FOR IMPROVING MOBILITY WITHIN SAID PETROLEUM-BEARING FORMATION, AND F. INJECTING A DIVING FLUID INTO SAID FORMATION AFTER SAID THIRD INJECTION.
Claim 2
Independent Claim
169 words
A METHOD OF TREATING PERTOLEUM-BEARING FORMATION WITH AN AQUEOUS SOLUTION OF SALT-SENSITIVE POLYMER TO CONTROL MOBILITY THE FORMATION FOR SECONDARY AND TERIARY RECOVERY, SAID METHOD COMPRISING, A, SELECTING AS SAID SALT-SENSETIVE POLYMER, COMPOUNDS OF WHICH THEVISCOSITY IS DECREASED BY INCREASING THE INORGANIC SALT CONCENTRATION IN AQUEOUS SOLUTION CONTAINING SUCH SALT-SENSETIVE POLYMERS, B. FORMING AN AQUEOUS MIXTURE OF SAID SALT-SENSITIVE POLYMER AND INORGANIC SALT TO FORM A HIGH BRIME CONCENTRATION MIXTURE C. INJECTING A FIRST INJECTION OF SAID BRIME MIXTURE INTO A PETROLEUM-BEARING FORMATION CONTANING HIGH BRIME WATER THEREIN, D. FOLLOWING THE INJECTION OF SAID HIGH BRIME MIXTURE WITH A SECOND INJECTION OF A HIGH BRIME AQUEOUS SOLUTION, E. FOLLOWING THE SECOND INJECTION WITH A THIRD INJECTION OF AN AQUEOUS BRIME SOLUTION WEAKER THAN SAID HIGH BRIME MIXTURE AND HIGH BRIME AQUEOUS SOLUTION THEREBY DECREASING THE SALT CONCENTRATION IN THE PETROLEUM-BEARING FORMATION BY ADMIXING WITH THE FIRST AND SECOND INJECTIONS FOR IMPROVING MOBILITY WITHIN SAID PETROLEUM-BEARING FORMATION, AND F. INJECTING A DIVING FLUID INTO SAID FORMATION AFTER SAID THIRD INJECTION.
Claim 3
Dependent Claim
37 words
The method as set forth in claim 1 wherein: a. said inorganic salt being in the quantity of at least approximately 3000 ppm to form said high brine aqueous solutions for said first injection and second injection.
Claim 4
Dependent Claim
49 words
The method as set forth in claim 2 wherein: a. said petroleum-bearing formation having a high brine aqueous solution of connate water therein initially with said aqueous polymer mixture being formed therewith and said second injection and driving fluid injection being made with the connate water from said formation.
Claim 5
Dependent Claim
83 words
The method as set forth in claim 2 wherein: a. said petroleum-bearing formations having a low brine aqueous solution therein initially and forming said aqueous polymer mixture therewith and adding inorganic salt to make same a high brine mixture, said high brine solution for said second injection being made with said low brine aqueous solution and additional inorganic salt; b. said driving fluid and said third injection of weak brine aqueous solution is said low brine aqueous solution and is a single step.
Claim 6
Dependent Claim
27 words
The method as set forth in claim 1 wherein: a. said salt-sensitive polymer is a water soluble polymer of acrylamide substantially linear and of high molecular weight.
Claim 7
Dependent Claim
22 words
The method as set forth in claim 1 wherein: a. said salt-sensitive polyacrylamide in the amount of approximately 25 to 50,000 ppm.
Claim 8
Dependent Claim
26 words
The method as set forth in claim 6 wherein: a. said high brine solutions have inorganic salt in the amount of at least approximately 3000 ppm.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-29 | 1979-03-31 | 1979-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-29 | 1983-03-31 | 1983-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-29 | 1987-03-31 | 1987-09-30 | $7700.00 | Window Closed / Lapsed |