US4434059A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polymers for prevention of fouling by iron oxides in cooling systems
Assignee: ChampionX LLC
•
Filing: 1982-11-18
•
Granted: 1984-02-28
•
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 07:48
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)
US2980610A
Cited
US3110666A
Cited
US3293152A
Cited
US3463730A
Cited
US3549548A
Cited
US3514736A
Cited
US4072607A
Cited
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 |