US4647385A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reduction of viscosity of aqueous fluids
Assignee: Stein Hall and Co Inc
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Filing: 1985-11-12
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Granted: 1987-03-03
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Expires: 2005-11-12
Abstract
Abstract The viscosity of thickened aqueous solutions of water-soluble polymers is reduced by the addition of alkali metal and alkaline earth metal salts of hypochlorous acid and tertiary amines. The combination of the salt and the tertiary amine is much more efficient in speed of reduction in viscosity and in the completeness of the degradation of the polymer than the use of the metal salt alone. The process of this invention is particularly useful in fracturing of oil wells.
Inventors
- 👤 Martin M. Williams
- 👤 Martha A. Phelps
- 👤 George M. Zody
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 14:59
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/60; C09K8/84; C09K8/86; C09K8/88; C09K8/62; Y; Y10; Y10S; Y10S507/00; Y10S507/921; Y10S507/922; Y10S507/925
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
117 words
A process for reducing the viscosity of aqueous fluids containing natural or synthetic water-soluble polymers selected from the groups consisting of water-soluble derivatives of cellulose, water-soluble polysaccharides, water-soluble derivatives of polysaccharides, polyacrylamide, polymethacrylamide, polyacrylic acid, copolymers of acrylic acid and acrylamide and mixtures thereof which comprises adding the aqueous fluid an alkali metal or alkaline earth metal salt of hypochlorous acid and a water-soluble tertiary amine, which contains one tertiary amine group and no other groups which are reactive in the process wherein about 0.25 to about 25 parts by weight of metal salt and about 0.25 to about 25 parts by weight of tertiary amine are present per each 100 parts by weight of water-soluble polymer.
Claim 2
Dependent Claim
117 words
A process for reducing the viscosity of aqueous fluids containing natural or synthetic water-soluble polymers selected from the groups consisting of water-soluble derivatives of cellulose, water-soluble polysaccharides, water-soluble derivatives of polysaccharides, polyacrylamide, polymethacrylamide, polyacrylic acid, copolymers of acrylic acid and acrylamide and mixtures thereof which comprises adding the aqueous fluid an alkali metal or alkaline earth metal salt of hypochlorous acid and a water-soluble tertiary amine, which contains one tertiary amine group and no other groups which are reactive in the process wherein about 0.25 to about 25 parts by weight of metal salt and about 0.25 to about 25 parts by weight of tertiary amine are present per each 100 parts by weight of water-soluble polymer.
Claim 3
Dependent Claim
40 words
The process of claim 1 wherein about 0.3 to about 1.0 part by weight of metal salt and about 0.3 to about 1.0 part by weight of tertiary amine are present per each 100 parts by weight of water-soluble polymer.
Claim 4
Dependent Claim
13 words
The process of claim 1 wherein the alkali metal salt is lithium hypochlorite.
Claim 5
Dependent Claim
11 words
The process of claim 1 wherein the tertiary amine is triethanolamine.
Claim 6
Dependent Claim
13 words
The process of claim 1 wherein the natural water-soluble polymer is hydroxypropyl guar.
Claim 7
Dependent Claim
13 words
The process of claim 1 wherein the synthetic water-soluble polymer is polyacrylic acid.
Claim 8
Dependent Claim
17 words
The process of claim 1 wherein the synthetic water-soluble is a copolymer of acrylic acid and acrylamide.
References Cited (Backward Citations)
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US3779914A
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US4144179A
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US4169798A
Cited
US4250044A
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US4464268A
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US4552668A
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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) | 1990-03-02 | 1990-09-01 | 1991-03-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-03-02 | 1994-09-01 | 1995-03-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-03-02 | 1998-09-01 | 1999-03-03 | $7700.00 | Window Closed / Lapsed |