Patent US4689154A successfully refreshed from Google Patents.
US4689154A
Expired / Lapsed
US
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Process for removing phosphorus from industrial waste water
Assignee: Occidental Chemical Corp
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Filing: 1985-11-15
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Granted: 1987-08-25
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Expires: 2005-11-15
Abstract
Abstract An improved process is described for removing phosphorus from industrial waste water by contacting the waste water with ozone to convert reduced or organic phosphates into ortho-phosphates, and precipitating the soluble ortho-phosphates by treatment with lime. The precipitated material can be filtered, and the filtrate treated with activated carbon to produce an effluent stream having low levels of phosphorus. The process of this invention is particularly effective at low treatment temperatures, enabling efficient treatment of the waste water during periods of cold weather.
Inventors
- 👤 Walter M. Zimberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 23:29
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/28; C02F1/283; C02F1/52; C02F1/5236; C02F1/72; C02F1/78; C02F9/00; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/906
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
109 words
A process for removing phosphorus from the effluent water from an elemental phosphorus production facility, said effluent water being stored in holding ponds adjacent to the facility, said process consisting essentially of the steps of: (a) contacting the pond water at a temperature of from about 0° C. to about 10° C. with ozone to convert reduced phosphates to ortho-phosphates, (b) contacting the pond water from step (a) with lime at a pH of from about 9 to about 10 to form a precipitate, (c) removing the precipitate by filtration, and (d) contacting the filtrate with an adsorbent material to produce water having a substantially reduced total phosphorus content.
Claim 2
Dependent Claim
109 words
A process for removing phosphorus from the effluent water from an elemental phosphorus production facility, said effluent water being stored in holding ponds adjacent to the facility, said process consisting essentially of the steps of: (a) contacting the pond water at a temperature of from about 0° C. to about 10° C. with ozone to convert reduced phosphates to ortho-phosphates, (b) contacting the pond water from step (a) with lime at a pH of from about 9 to about 10 to form a precipitate, (c) removing the precipitate by filtration, and (d) contacting the filtrate with an adsorbent material to produce water having a substantially reduced total phosphorus content.
Claim 3
Dependent Claim
19 words
The process of claim 1 wherein the waste water is contacted with ozone in the presence of ultraviolet radiation.
Claim 4
Dependent Claim
12 words
The process of claim 1 wherein the adsorbent material is activated carbon.
Claim 5
Dependent Claim
113 words
A process for removing phosphorus from the effluent water from an elemental phosphorus production facility, said effluent water being stored in holding ponds adjacent to the facility, said process consisting essentially of the steps of: (a) contacting the pond water at a temperature of from about 0° C. to about 10° C. with ozone to convert reduced phosphates to orthophosphates, (b) contacting the pond water from step (a) with lime at a pH of from about 9 to about 10 to form a precipitate, (c) aerating the pond water, (d) removing the precipitate by filtration, and (e) contacting the filtrate with activated carbon to produce water having a substantially reduced total phosphorus content.
Claim 6
Dependent Claim
113 words
A process for removing phosphorus from the effluent water from an elemental phosphorus production facility, said effluent water being stored in holding ponds adjacent to the facility, said process consisting essentially of the steps of: (a) contacting the pond water at a temperature of from about 0° C. to about 10° C. with ozone to convert reduced phosphates to orthophosphates, (b) contacting the pond water from step (a) with lime at a pH of from about 9 to about 10 to form a precipitate, (c) aerating the pond water, (d) removing the precipitate by filtration, and (e) contacting the filtrate with activated carbon to produce water having a substantially reduced total phosphorus content.
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) | 1990-08-24 | 1991-02-23 | 1991-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-24 | 1995-02-23 | 1995-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-24 | 1999-02-23 | 1999-08-25 | $7700.00 | Window Closed / Lapsed |