US3557873A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for improving the injectivity of water injection wells
Assignee: Union Oil Company of California
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Filing: 1968-07-29
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Granted: 1971-01-26
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Expires: 1988-07-29
Abstract
Abstract The injection rate of water into water injection wells that exhibit low injectivity because of oil saturation in the formation adjacent to the well can be increased by introducing a small quantity of soluble oil into the well, and thereafter displacing the soluble oil into the formation with subsequently injected flood water. This treatment removes almost all of the oil from the formation adjacent to the well, thereby increasing the relative permeability of the formation to water.
Inventors
- 👤 William D Owens
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 18:28
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/58
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
35 words
The method defined in claim 1 wherein sufficient soluble oil is introduced into said reservoir to remove oil from said reservoir to a distance of up to 5 to 10 feet from said injection well.
Claim 2
Dependent Claim
29 words
The method defined in claim 1 wherein between about 0.05 to 0.5 barrels of soluble oil is injected into said reservoir per foot of vertical thickness of said reservoir.
Claim 3
Dependent Claim
18 words
The method defined in claim 1 wherein said soluble oil comprises hydrocarbon liquid, organic stabilizing agent, and surfactant.
Claim 4
Dependent Claim
28 words
The method defined in claim 1 wherein said soluble oil is a water-in-oil microemulsion comprised of hydrocarbon liquid, organic stabilizing agent, surfactant, and about 4 volume percent water.
Claim 5
Dependent Claim
99 words
In the injection of aqueous liquid through an injection well and into a porous subterranean formation containing oil which is resistant to displacement by said aqueous liquid, and which subsequently restricts the passage of said aqueous liquid through the formation, the improvement which comprises removing said oil from the formation immediately adjacent to said well by introducing a substantially anhydrous soluble oil into the formation adjacent to the well in an amount not greater than about 1 barrel per foot of vertical thickness of the formation, and thereafter injecting said aqueous liquid through said well and into said formation.
Claim 6
Dependent Claim
35 words
The method defined in claim 6 wherein sufficient soluble oil is introduced into said reservoir to remove oil from said formation to a distance of up to 5 to 10 feet from said injection well.
Claim 7
Dependent Claim
29 words
The method defined in claim 6 wherein between about 0.05 to 0.5 barrels of soluble oil is injected into said formation per foot oF vertical thickness of said formation.
Claim 8
Dependent Claim
20 words
The method defined in claim 6 wherein said soluble oil comprises hydrocarbon liquid, an organic stabilizing agent, and a surfactant.
Claim 9
Dependent Claim
28 words
The method defined in claim 6 wherein said soluble oil is a water-in-oil microemulsion comprised of hydrocarbon liquid, organic stabilizing agent, surfactant, and about 4 volume percent water.
Claim 10
Independent Claim
100 words
A method for improving the injectivity of water into a porous subterranean oil-bearing formation penetrated by a water injection well, which comprises: injecting water through said injection well and into said formation at a first injection rate; introducing a small volume of a substantially anhydrous soluble oil into the formation adjacent to the well in an amount sufficient to remove oil from said formation to a distance of up to 5 to 10 feet from said injection well; and thereafter injecting water through said injection well and into said formation at an injection rate higher than said first injection rate.
Claim 11
Dependent Claim
32 words
The method defined in claim 11 wherein said soluble oil is injected into the formation in an amount not greater than about 1 barrel per foot of vertical thickness of the formation.
Claim 12
Dependent Claim
28 words
The method defined in claim 11 wherein said soluble oil is a water-in-oil microemulsion comprised of hydrocarbon liquid, organic stabilizing agent, surfactant and about 4 volume percent water.
Claim 13
Dependent Claim
18 words
The method defined in claim 11 wherein said soluble oil comprises hydrocarbon liquid, organic stabilizing agent, and surfactant.
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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) | 1974-01-25 | 1974-07-27 | 1975-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-25 | 1978-07-27 | 1979-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-25 | 1982-07-27 | 1983-01-26 | $7700.00 | Window Closed / Lapsed |