US3962110A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and composition for preventing scale build-up
Assignee: Texaco Inc
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Filing: 1974-10-04
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Granted: 1976-06-08
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Expires: 1994-10-04
Abstract
Abstract A process and composition for the treatment of oil and gas wells to prevent and/or inhibit the build-up of an undesirable inorganic mineral scale deposits in which an aqueous solution of a vinylpyrrolidone polymer is employed in an amount sufficient to prevent and/or inhibit the development of such scale.
Inventors
- 👤 Jack F. Tate
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:45
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/12; Y; Y10; Y10S; Y10S507/00; Y10S507/927
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
123 words
A process for controlling the build-up of inorganic mineral scale deposits in an aqueous system which comprises incorporating in said system a composition consisting essentially of a water-soluble polyvinylpyrrolidone, the said polyvinylpyrrolidone being present in an amount sufficient to inhibit the development of scale, wherein the said polyvinylpyrrolidone comprises recurring units of the formula: ##SPC3## wherein R, R a , R b and R c are independently selected from the group consisting of hydrogen and alkyl of from 1 to 5 inclusive carbon atoms, and the molecular weight of the said polyvinylpyrrolidone being from about 10,000 to about 1,000,000; and wherein the said system is made acidic through the addition of up to about 30 percent by weight of a non-oxidizing mineral acid.
Claim 2
Dependent Claim
123 words
A process for controlling the build-up of inorganic mineral scale deposits in an aqueous system which comprises incorporating in said system a composition consisting essentially of a water-soluble polyvinylpyrrolidone, the said polyvinylpyrrolidone being present in an amount sufficient to inhibit the development of scale, wherein the said polyvinylpyrrolidone comprises recurring units of the formula: ##SPC3## wherein R, R a , R b and R c are independently selected from the group consisting of hydrogen and alkyl of from 1 to 5 inclusive carbon atoms, and the molecular weight of the said polyvinylpyrrolidone being from about 10,000 to about 1,000,000; and wherein the said system is made acidic through the addition of up to about 30 percent by weight of a non-oxidizing mineral acid.
Claim 3
Dependent Claim
20 words
The process of claim 1 wherein the said polyvinylpyrrolidone has a molecular weight of from about 100,000 to about 400,000.
Claim 4
Dependent Claim
28 words
The process of claim 1 wherein the said polyvinylpyrrolidone is present in said aqueous system in a concentration of from about 0.0005 to about 0.02 percent by weight.
Claim 5
Dependent Claim
28 words
The process of claim 1 wherein the said polyvinylpyrrolidone is present in said aqueous system in a concentration of from about 0.0005 to about 0.01 percent by weight.
Claim 6
Dependent Claim
49 words
The process of claim 1 wherein the said polyvinylpyrrolidone is present in said system in a concentration of from about 0.0005 to about 0.02 percent by weight and wherein the said system is made acidic through the addition of up to about 30 percent by weight of hydrochloric acid.
Claim 7
Dependent Claim
16 words
The process of claim 1 wherein the said inorganic mineral scale deposit is iron salt scale.
Claim 8
Dependent Claim
62 words
An inorganic mineral scale-inhibiting composition comprising an aqueous solution of polyvinylpyrrolidone having a molecular weight of from about 10,000 to about 1,000,000, the said polymer being present in an amount of from about 0.0005 to about 0.02 percent by weight and wherein the said solution is an acidic solution containing up to about 30 percent by weight of a non-oxidizing mineral acid.
Claim 9
Dependent Claim
62 words
An inorganic mineral scale-inhibiting composition comprising an aqueous solution of polyvinylpyrrolidone having a molecular weight of from about 10,000 to about 1,000,000, the said polymer being present in an amount of from about 0.0005 to about 0.02 percent by weight and wherein the said solution is an acidic solution containing up to about 30 percent by weight of a non-oxidizing mineral acid.
Claim 10
Dependent Claim
47 words
The scale-inhibiting composition of claim 7 wherein the said polyvinylpyrrolidone polymer comprises recurring units of the formula: ##SPC4## wherein R, R a , R b and R c are independently selected from the group consisting of hydrogen and alkyl of from 1 to 5 inclusive carbon atoms.
Claim 11
Dependent Claim
22 words
The composition of claim 7 wherein the said polymer is polyvinylpyrrolidone having a molecular weight of from about 100,000 to about 400,000.
Claim 12
Dependent Claim
26 words
The composition of claim 7 wherein the said aqueous solution is an acidic aqueous solution containing up to about 30 percent by weight of hydrochloric acid.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-08 | 1979-12-08 | 1980-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-08 | 1983-12-08 | 1984-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-08 | 1987-12-08 | 1988-06-08 | $7700.00 | Window Closed / Lapsed |