Patent US4434059A successfully refreshed from Google Patents.
US4434059A
Expired / Lapsed
US
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Polymers for prevention of fouling by iron oxides in cooling systems
Assignee: ChampionX LLC
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Filing: 1982-11-18
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Granted: 1984-02-28
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Expires: 2002-11-18
Abstract
Abstract Industrial process cooling water systems are stabilized against iron precipitation by adding thereto an effective amount of an acrylic acid-acrylamide copolymer having specific weight ratios.
Inventors
- 👤 Donald A. Johnson
- 👤 Baker N. Nimry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 14:29
CPC Classifications
C; C02; C02F; C02F5/00; C02F5/08; C02F5/10; C02F5/12
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
71 words
A method for the stabilization of water containing iron and calcium ions said water being utilized in an industrial process cooling system operating at a pH of from 6-11, which comprises adding to the water containing iron and calcium ions an effective amount of a copolymer of acrylic acid and acrylamide having a molecular weight of approximately 10,000 the ratio of acrylic acid to acrylamide being 25:75 on a weight basis.
Claim 2
Independent Claim
71 words
A method for the stabilization of water containing iron and calcium ions said water being utilized in an industrial process cooling system operating at a pH of from 6-11, which comprises adding to the water containing iron and calcium ions an effective amount of a copolymer of acrylic acid and acrylamide having a molecular weight of approximately 10,000 the ratio of acrylic acid to acrylamide being 25:75 on a weight basis.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein the iron contained in the water is in the form of Fe+3.
Claim 4
Dependent Claim
21 words
The method of claim 2 wherein the water containing Fe+3 is generated by the oxidation of Fe+2 contained in ground water.
Claim 5
Dependent Claim
16 words
The method of claim 1 wherein the industrial process cooling system is an open recirculating system.
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) | 1987-02-27 | 1987-08-29 | 1988-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-27 | 1991-08-29 | 1992-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-27 | 1995-08-29 | 1996-02-28 | $7700.00 | Window Closed / Lapsed |