US4466892A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Caustic flooding with stabilized water for enhanced oil recovery
Assignee: Standard Oil Co
•
Filing: 1982-01-28
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Granted: 1984-08-21
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Expires: 2002-01-28
Abstract
Abstract An improved method for enhanced oil recovery utilizing caustic or alkaline water flooding which avoids precipitation of hydroxides in the injection water or plugging of the reservoir. A lignosulfonate material is blended with the injection water before the addition of the alkaline chemical, the amount of lignosulfonate being sufficient to prevent formation of any precipitates.
Inventors
- 👤 Keng S. Chan
- 👤 Stephen J. Majoros
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 01:54
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/84; C09K8/86; C09K8/88; C09K8/885; Y; Y10; Y10S; Y10S507/00; Y10S507/935; Y10S507/936
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
86 words
A process for producing petroleum from oil-bearing reservoirs by driving a fluid from at least one injection well to a producing well, the process comprising injecting via the injection well a blend of injection water containing divalent metal ions, lignosulfonate in an amount sufficient to prevent significant precipitation of insoluble compounds, and an alkaline material selected from the group consisting of sodium hydroxide, sodium carbonate, trisodium phosphate, and ammonia, provided that the lignosulfonate is mixed with the injection water before the addition of the alkaline material.
Claim 2
Dependent Claim
86 words
A process for producing petroleum from oil-bearing reservoirs by driving a fluid from at least one injection well to a producing well, the process comprising injecting via the injection well a blend of injection water containing divalent metal ions, lignosulfonate in an amount sufficient to prevent significant precipitation of insoluble compounds, and an alkaline material selected from the group consisting of sodium hydroxide, sodium carbonate, trisodium phosphate, and ammonia, provided that the lignosulfonate is mixed with the injection water before the addition of the alkaline material.
Claim 3
Dependent Claim
13 words
The process of claim 1 in which the alkaline material is sodium hydroxide.
Claim 4
Dependent Claim
12 words
The process of claim 2 in which the injection water comprises seawater.
Claim 5
Dependent Claim
19 words
The process of claim 3 in which the lignosulfonate is added to the injection water in a pre-solubilized form.
Claim 6
Dependent Claim
14 words
The process of claim 3 in which the lignosulfonate is in a powdered form.
Claim 7
Dependent Claim
19 words
The process of claim 3 in which the blend to be injected comprises at least 1 wt % lignosulfonate.
Claim 8
Dependent Claim
16 words
The process of claim 6 in which the blend comprises at least 3 wt % lignosulfonate.
References Cited (Backward Citations)
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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) | 1987-08-21 | 1988-02-20 | 1988-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-21 | 1992-02-20 | 1992-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-21 | 1996-02-20 | 1996-08-21 | $7700.00 | Window Closed / Lapsed |