Patent US3724544A successfully refreshed from Google Patents.
US3724544A
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Secondary recovery method
Assignee: Texaco Inc
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Filing: 1971-06-21
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Granted: 1973-04-03
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Expires: 1991-06-21
Abstract
Abstract Significant improvement in the recovery of hydrocarbons from a subterranean hydrocarbon-bearing formation containing acidsoluble components is accomplished by injecting into the formation via an injection well drilled into a formation communicating with an adjacent producing well and containing acid-soluble components which may or may not have water-sensitive clays and shales included therein, an aqueous acidic solution of a phosphate ester of prescribed formula whereupon the acid component reacts with the acid-soluble components of the formation creating passageways or enlarging existing passageways thus facilitating the flow of fluids therein and the phosphate ester prevents post-precipitation of dissolved salts and thereby increases the recovery of hydrocarbons from the formation through the adjacent producing well.
Inventors
- 👤 J Tate
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:54
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/62; C09K8/72; C09K8/74
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
28 words
Method as claimed in claim 1 wherein said ester is a monoester of phosphoric acid esterified with an ethoxylated nonylphenol containing from about 6 to 10 ethoxy groups.
Claim 2
Dependent Claim
28 words
Method as claimed in claim 1 wherein said ester is a diester of phosphoric acid esterified with an ethoxylated nonylphenol containing from about 6 to 10 ethoxy groups.
Claim 3
Dependent Claim
29 words
Method as claimed in claim 1 wherein said ester is a monoester of phosphoric acid esterified with an ethoxylated C12-C18 alkanol containing from about 6 to 10 ethoxy groups.
Claim 4
Dependent Claim
29 words
Method as claimed in claim 1 wherein said ester is a diester of phosphoric acid esterified with an ethoxylated C12-C18 alkanol containing from about 6 to 10 ethoxy groups.
Claim 5
Dependent Claim
33 words
Method as claimed in claim 1 wherein said ester is an admixture of a monoester and a diester of phosphoric acid esterified with an ethoxylated nonylphenol containing from 6 to 10 ethoxy groups.
Claim 6
Dependent Claim
37 words
Method as claimed in claim 1 wherein said ester consists essentially of a mixture of a monoester and a diester of phosphoric acid esterified with an ethoxylated C12-C18 alkanol containing from about 6 to 10 ethoxy groups.
Claim 7
Dependent Claim
41 words
Method as claimed in claim 1 wherein said ester comprises a mixture of 40- 60 percent by weight of nonylphenoxypolyethoxyethyl phosphate and 60- 40 percent by weight of di(nonylphenoxypolyethoxyethyl) phosphate, each polyethoxy moiety containing an average of about 5 ethoxy groups.
Claim 8
Dependent Claim
29 words
The method as claimed in claim 1 wherein the said ester is present in the composition in an amount of from about 0.3 to about 1.5 percent by weight.
Claim 9
Dependent Claim
13 words
The method as claimed in claim 1 wherein said acid is hydrochloric acid.
Claim 10
Dependent Claim
13 words
The method as claimed in claim 1 wherein said acid is sulfuric acid.
Claim 11
Dependent Claim
27 words
The method as claimed in claim 1 wherein the said ester is dissolved in about 5 to about 20 percent by weight solution of the mineral acid.
Claim 12
Dependent Claim
36 words
Method as claimed in claim 1 wherein the said solution is injected down the injection well bore penetrating said formation under a pressure greater than the formation pressure and sufficient to create fractures in the formation.
Claim 13
Dependent Claim
38 words
Method as claimed in claim 1 wherein the said solution is injected down the well bore penetrating said formation under a pressure greater than formation pressure but less than the pressure required to create fractures in the formation.
Claim 14
Independent Claim
173 words
A method for the recovery of hydrocarbons from a hydrocarbon-bearing formation containing acid-soluble components and having at least one injection well and at least one production well penetrating the said formation in fluid communication which comprises displacing through the formation a slug of a composition comprising an aqueous acidic solution of a phosphate ester containing 3-30 percent by weight of a non-oxidizing mineral acid and 0.1 to 2.5 percent by weight of said phosphate ester, said phosphate ester having the general formula: wherein R is a C6-C12 alkylphenyl radical or a C12-C18 alkyl radical, A is hydrogen or an alkali metal, n is a number from 1 to 20, both x and y are 1 or 2 and the sum of x and y is 3, said ester having a molecular weight in the range of from about 500 to about 1,000, thereafter injecting a slug of an aqueous drive fluid into the formation to drive the said composition through the formation toward said production well and recovering hydrocarbons through the production well.
Claim 15
Dependent Claim
30 words
Method as claimed in claim 15 wherein said phosphate ester is a monoester of phosphoric acid esterified with an ethoxylated nonylphenol containing from about 6 to about 10 ethoxy groups.
Claim 16
Dependent Claim
29 words
Method as claimed in claim 15 wherein said phosphate ester is a diester of phosphoric acid esterified with an ethoxylated nonylphenol containing from about 6 to 10 ethoxy groups.
Claim 17
Dependent Claim
30 words
Method as claimed in claim 15 wherein said phosphate ester is a monoester of phosphoric acid esterified with an ethoxylated C12-C18 alkanol containing from about 6 to 10 ethoxy groups.
Claim 18
Dependent Claim
30 words
Method as claimed in claim 15 wherein said phosphate ester is a diester of phosphoric acid esterified with an ethoxylated C12-C18 alkanol Containing from about 6 to 10 ethoxy groups.
Claim 19
Dependent Claim
34 words
Method as claimed in claim 15 wherein said phosphate ester is an admixture of a monoester and a diester of phosphoric acid esterified with an ethoxylated nonylphenol containing from 6 to 10 ethoxy groups.
Claim 20
Dependent Claim
37 words
Method as claimed in claim 15 wherein said ester consists essentially of a mixture of a monoester and a diester of phosphoric acid esterified with an ethoxylated C12-C18 alkanol containing from about 6 to 10 ethoxy groups.
Claim 21
Dependent Claim
41 words
Method as claimed in claim 15 wherein said ester comprises a mixture of 40- 60 percent by weight of nonylphenoxypolyethoxyethyl phosphate and 60- 40 percent by weight of di(nonylphenoxypolyethoxyethyl) phosphate, each polyethoxy moiety containing an average of about 5 ethoxy groups.
Claim 22
Dependent Claim
27 words
Method as claimed in claim 15 wherein said ester is present in the composition in an amount of from about 0.3 to about 1.5 percent by weight.
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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) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |