US4243525A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for reducing the formation of trihalomethanes in drinking water
Assignee: FMC Corp
•
Filing: 1979-03-29
•
Granted: 1981-01-06
•
Expires: 1999-03-29
Abstract
Abstract The level of trihalomethanes in drinking water is reduced by adding hydrogen peroxide to the water prior to chlorination.
Inventors
- 👤 Edward S. Greenberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:55
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/72; C02F1/722; C02F1/76
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
83 words
A method of treating water to disinfect the water and reduce the formation of trihalomethanes which comprises first adding to the water from about 0.1 to about 50 parts per million hydrogen peroxide to oxidize organic substances present therein and thereafter adding to the water sufficient chlorine to react with any hydrogen peroxide present and maintain a residual amount of chlorine sufficient to disinfect the water, whereby the formation of trihalomethanes present in the water amounts to less than 295 parts per billion.
Claim 2
Independent Claim
83 words
A method of treating water to disinfect the water and reduce the formation of trihalomethanes which comprises first adding to the water from about 0.1 to about 50 parts per million hydrogen peroxide to oxidize organic substances present therein and thereafter adding to the water sufficient chlorine to react with any hydrogen peroxide present and maintain a residual amount of chlorine sufficient to disinfect the water, whereby the formation of trihalomethanes present in the water amounts to less than 295 parts per billion.
Claim 3
Dependent Claim
23 words
The method of claim 1 wherein the chlorine is added from about 0.5 to about 24 hours after addition of the hydrogen peroxide.
Claim 4
Dependent Claim
25 words
The method of claim 1 wherein the amount of hydrogen peroxide added to the water is from about 1 to about 10 parts per million.
Claim 5
Dependent Claim
22 words
The method of claim 1 wherein the formation of trihalomethanes present in the water amounts to less than 100 parts per billion.
Claim 6
Dependent Claim
16 words
The method of claim 1 wherein said hydrogen peroxide is added subsequent to a coagulation step.
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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) | 1984-01-06 | 1984-07-07 | 1985-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-06 | 1988-07-07 | 1989-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-06 | 1992-07-07 | 1993-01-06 | $7700.00 | Window Closed / Lapsed |