US4402833A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Waste water treatment system for elemental phosphorous removal
Assignee: Occidental Chemical Corp
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Filing: 1981-02-24
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Granted: 1983-09-06
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Expires: 2001-02-24
Abstract
Abstract An environmentally sound system for the removal of elemental phosphorus from waste water resulting from phosphorus manufacture, use, conversion to other products, and storage, wherein the waste water is treated with a material such as lime that produces an insoluble phosphate, filtering the precipitate and passing the filtrate through a column of an adsorbent, such as activated carbon, to produce elemental phosphorus-free water which can be discarded without deleterious effects to the environment.
Inventors
- 👤 W. Clark Bennett
- 👤 Theodore T. Garrett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:58
CPC Classifications
C; C02; C02F; C02F9/00; C02F1/00; C02F1/28; C02F1/283; C02F1/52; C02F1/5236; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/906
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
76 words
A process for the preparation of essentially elemental phosphorus-free water from industrial waste water comprising the steps of: (a) treating the industrial waste water with lime at a pH of from about 9 to about 10 to precipitate soluble phosphates, (b) aerating the mixture with air, (c) removing the precipitate by filtration, and (d) passing the filtrate through a bed of activated carbon to produce water which can be discarded without deleterious effects to the environment.
Claim 2
Dependent Claim
76 words
A process for the preparation of essentially elemental phosphorus-free water from industrial waste water comprising the steps of: (a) treating the industrial waste water with lime at a pH of from about 9 to about 10 to precipitate soluble phosphates, (b) aerating the mixture with air, (c) removing the precipitate by filtration, and (d) passing the filtrate through a bed of activated carbon to produce water which can be discarded without deleterious effects to the environment.
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) | 1986-09-05 | 1987-03-07 | 1987-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-05 | 1991-03-07 | 1991-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-05 | 1995-03-07 | 1995-09-06 | $7700.00 | Window Closed / Lapsed |