US4078607A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Oil recovery process using improved thickened aqueous flooding liquids
Assignee: Texaco Inc
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Filing: 1976-09-13
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Granted: 1978-03-14
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Expires: 1996-09-13
Abstract
Abstract The specification discloses a process for recovering oil from a subterranean reservoir which process utilizes a thickened flooding liquid containing polysaccharide B-1459. In the process the polysaccharide B-1459 is imparted with superior viscosity by first prehydrating it with fresh or deionized water before mixing with another aqueous component, for example brine water containing large amounts or inorganic ions, that is, hard water. The invention comprises the polysaccharide B-1459 which has been prehydrated in the fresh or deionized aqueous medium and then mixed with hard water. The process for imparting viscosity to polysaccharide B-1459 is an improvement over the prior art in that a higher viscosity is obtained while using the same amount of polysaccharide that has been obtained by hydrating the polysaccharide in hard or brine water initially.
Inventors
- 👤 Walter H. Carter
- 👤 Charles A. Christopher
- 👤 Thomas Jefferson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:50
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/84; C09K8/86; C09K8/88; C09K8/90; C09K8/905
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
85 words
In a method for recovering oil from a subterranean reservoir having injection and production means wherein an aqueous polysaccharide B-1459 solution is injected into the reservoir via the injection means and oil is produced from the production means the improvement which comprises using a superior aqueous polysaccharide solution made by prehydrating the polysaccharide in fresh water and then mixing this prehydrated solution with hard water whereby said prehydration step yields a polysaccharide solution in hard water of higher viscosity than hydrating directly in hard water.
Claim 2
Dependent Claim
85 words
In a method for recovering oil from a subterranean reservoir having injection and production means wherein an aqueous polysaccharide B-1459 solution is injected into the reservoir via the injection means and oil is produced from the production means the improvement which comprises using a superior aqueous polysaccharide solution made by prehydrating the polysaccharide in fresh water and then mixing this prehydrated solution with hard water whereby said prehydration step yields a polysaccharide solution in hard water of higher viscosity than hydrating directly in hard water.
Claim 3
Dependent Claim
20 words
A method in claim 1 wherein the fresh water contains inorganic ions in concentrations below about 15,000 g/m 3 .
Claim 4
Dependent Claim
21 words
A method as in claim 1 wherein the fresh water contains inorganic ions in concentrations below about 6,000 g/m 3 .
Claim 5
Dependent Claim
16 words
A method as in claim 1 wherein the polysaccharide solution is preceded by a water drive.
Claim 6
Dependent Claim
90 words
In a method for recovering oil from a subterranean reservoir having injection and production means wherein a surfactant solution is injected into the reservoir via the injection means followed by an aqueous polysaccharide B-1459 solution and oil is produced from the production means the improvement which comprises injecting a superior aqueous polysaccharide solution made by prehydrating the polysaccharide in fresh water and then mixing this prehydrated solution with hard water whereby said prehydration step yields a polysaccharide solution in hard water of higher viscosity than hydrating directly in hard water.
Claim 7
Dependent Claim
90 words
In a method for recovering oil from a subterranean reservoir having injection and production means wherein a surfactant solution is injected into the reservoir via the injection means followed by an aqueous polysaccharide B-1459 solution and oil is produced from the production means the improvement which comprises injecting a superior aqueous polysaccharide solution made by prehydrating the polysaccharide in fresh water and then mixing this prehydrated solution with hard water whereby said prehydration step yields a polysaccharide solution in hard water of higher viscosity than hydrating directly in hard water.
Claim 8
Dependent Claim
21 words
A method as in claim 5 wherein the fresh water contains inorganic ions in concentrations below about 15,000 g/m 3 .
Claim 9
Dependent Claim
21 words
A method as in claim 5 wherein the fresh water contains inorganic ions in concentrations below about 6,000 g/m 3 .
Claim 10
Dependent Claim
85 words
In a method for recovering oil from a subterranean reservoir having injection and production means wherein an aqueous polysaccharide B-1459 solution is injected into the reservoir via the injection means and oil is produced from the production means the improvement which comprises using a superior aqueous polysaccharide solution made by prehydrating the polysaccharide in deionized water and then mixing this prehydrated solution with hard water whereby said prehydration step yields a polysaccharide solution in hard water of higher viscosity than hydrating directly in hard water.
Claim 11
Dependent Claim
85 words
In a method for recovering oil from a subterranean reservoir having injection and production means wherein an aqueous polysaccharide B-1459 solution is injected into the reservoir via the injection means and oil is produced from the production means the improvement which comprises using a superior aqueous polysaccharide solution made by prehydrating the polysaccharide in deionized water and then mixing this prehydrated solution with hard water whereby said prehydration step yields a polysaccharide solution in hard water of higher viscosity than hydrating directly in hard water.
Claim 12
Dependent Claim
16 words
A method as in claim 8 wherein the polysaccharide solution is preceded by a water drive.
Claim 13
Dependent Claim
90 words
In a method for recovering oil from a subterranean reservoir having injection and production means wherein a surfactant solution is injected into the reservoir via the injection means followed by an aqueous polysaccharide B-1459 solution and oil is produced from the production means the improvement which comprises using a superior aqueous polysaccharide solution made by prehydrating the polysaccharide in deionized water and then mixing this prehydrated solution with hard water whereby said prehydration step yields a polysaccharide solution in hard water of higher viscosity than hydrating directly in hard water.
Claim 14
Dependent Claim
90 words
In a method for recovering oil from a subterranean reservoir having injection and production means wherein a surfactant solution is injected into the reservoir via the injection means followed by an aqueous polysaccharide B-1459 solution and oil is produced from the production means the improvement which comprises using a superior aqueous polysaccharide solution made by prehydrating the polysaccharide in deionized water and then mixing this prehydrated solution with hard water whereby said prehydration step yields a polysaccharide solution in hard water of higher viscosity than hydrating directly in hard water.
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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) | 1981-03-13 | 1981-09-12 | 1982-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-03-13 | 1985-09-12 | 1986-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-03-13 | 1989-09-12 | 1990-03-14 | $7700.00 | Window Closed / Lapsed |