Patent US3725266A successfully refreshed from Google Patents.
US3725266A
Expired / Lapsed
US
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Process for removing metal compound contaminants from waste water
Assignee: HAVILAND PROD CO
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Filing: 1971-08-12
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Granted: 1973-04-03
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Expires: 1991-08-12
Abstract
Abstract A process for removing one or more metal compound contaminants from contaminated industrial waste water comprising precipitating the metal compound contaminants from the waste water to form an aqueous metal compound sludge, allowing the sludge to settle, concentrating the sludge by centrifugation and reclaiming the metal compound contaminants from the sludge for reuse as either the metal compounds or the free metals.
Inventors
- 👤 J Haviland
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:24
CPC Classifications
C; C02; C02F; C02F9/00; C02F1/00; C02F1/46; C02F1/461; C02F1/467; C02F1/4676; C02F1/4678; C02F1/52; C02F1/5236; C02F2101/00; C02F2101/10; C02F2101/20; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/911; Y10S210/912; Y10S210/913; Y10S210/914
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
19 words
A process according to claim 1 wherein said centrifugation is conducted at a force of at least 1,400 gravities.
Claim 2
Dependent Claim
20 words
A process according to claim 1 wherein a coagulating agent is added to said waste water prior to said centrifugation.
Claim 3
Dependent Claim
13 words
A process according to claim 3 wherein said coagulating agent is a polyelectrolyte.
Claim 4
Dependent Claim
33 words
A process according to claim 1 wherein said metal compound contaminants comprise one or more of the group consisting of aluminum, cadmium, copper, chromium, iron, manganese, mercury, lead, nickel, silver, tin and zinc.
Claim 5
Dependent Claim
26 words
A process according to claim 1 wherein said concentrated metal compound sludge is transferred to an electrolysis tank and the free metal is recovered by elEctrolysis.
Claim 6
Dependent Claim
25 words
A process according to claim 1 wherein said concentrated metal compound sludge is transferred to a dissolution tank wherein said metal compound contaminants are dissolved.
Claim 7
Dependent Claim
16 words
A process according to claim 7 wherein said dissolved metal compound contaminants are recovered by recrystallization.
Claim 8
Dependent Claim
57 words
A process according to claim 1 wherein said centrifugation is conducted on a continuous basis and wherein the transference of said aqueous metal compound sludge to said centrifuge is interrupted each time the centrifuge bowl becomes filled with solids to facilitate a greater discharge of the effluent and compaction of the solids before said bowl is emptied.
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) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |