US4419327A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of scavenging dissolved oxygen in steam generating equipment using ammonia or amine neutralized erythorbic acid
Assignee: ChampionX LLC
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Filing: 1981-12-22
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Granted: 1983-12-06
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Expires: 2001-12-22
Abstract
Abstract A method of scavenging oxygen and passivating metal surfaces in steam generating equipment by treating feedwater with an ammonia or amine neutralized erythorbate form thereof.
Inventors
- 👤 John A. Kelly
- 👤 Cynthia A. Soderquist
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:24
CPC Classifications
C; C23; C23F; C23F11/00; C23F11/08; C23F11/10; C23F11/12; C23F11/124; C23F11/126
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
39 words
A method of removing dissolved oxygen from boiler feedwater and passivating boiler metal surfaces comprising adding to said boiler feedwater an oxygen scavenging amount of an ammonium or amine neutralized erythorbate at a pH of at least about 5.0.
Claim 2
Independent Claim
39 words
A method of removing dissolved oxygen from boiler feedwater and passivating boiler metal surfaces comprising adding to said boiler feedwater an oxygen scavenging amount of an ammonium or amine neutralized erythorbate at a pH of at least about 5.0.
Claim 3
Dependent Claim
11 words
The method of claim 1 wherein ammonium neutralized erythorbate is used.
Claim 4
Dependent Claim
26 words
The method of claim 2 wherein said ammonium neutralized erythorbic acid is added to said feedwater at a level of at least 0.025 ppm by weight.
Claim 5
Dependent Claim
17 words
The method of claim 2 wherein said ammonium neutralized erythorbate solution is pH adjusted to about 6.0±0.5.
Claim 6
Dependent Claim
11 words
The method of claim 2 wherein a pro-oxidant catalyst is utilized.
Claim 7
Dependent Claim
21 words
The method of claim 2 wherein said catalyst is utilized at a level of at least about 5 ppb by weight.
Claim 8
Dependent Claim
18 words
The method of claim 2 wherein said catalyst is chosen from the group comprising copper, nickel and iron.
Claim 9
Dependent Claim
35 words
The method of claim 2 wherein said pH is at least about pH 6.0±0.5 and said ammonium neutralized erythorbate is added to said feedwater at a level of at least about 0.01 ppm by weight.
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) | 1986-12-05 | 1987-06-06 | 1987-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-05 | 1991-06-06 | 1991-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-05 | 1995-06-06 | 1995-12-06 | $7700.00 | Window Closed / Lapsed |