US3772190A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for purifying water
Assignee: DUERR O KG
•
Filing: 1971-10-08
•
Granted: 1973-11-13
•
Expires: 1991-10-08
Abstract
Abstract A method for purifying polluted water by adding compressed air and intimately mixing it by circulation in a first operating stage so as to form a foamy mixture, then allowing the foam to float to the surface of the water and removing the foam and thereby partly cleaning the water, then subjecting the partly clean water to a second operating stage in which compressed air is again added to the water and the mixture is again thoroughly circulated and intimately mixed to produce a foam, and the foam is again allowed to float to the surface of the water, and then removing all of the foam from the cleaned water.
Inventors
- 👤 R Eisenmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:31
CPC Classifications
B; B03; B03D; B03D1/00; B03D1/02; B03D1/028; B03D1/14; B03D1/1406; B03D1/1443; B03D1/1462; B03D1/24; B03D1/247
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
23 words
A method as defined in claim 1 in which a coagulating agent is added to the polluted water in the first mixing container.
Claim 2
Dependent Claim
34 words
A method as defined in claim 1 in which water from the first separating container is recirculated under pressure into the one of the two mixing containers to produce an additional injector effect therein.
Claim 3
Dependent Claim
28 words
A method as defined in claim 1 in which the foams that are separated in the first and second separating containers are simultaneously withdrawn from the separating containers.
Claim 4
Dependent Claim
43 words
A method as defined in claim 1 in which the foam collected at the surface of the water in the second separating container is moved toward and combined with the foam from the first separating container solely under the influence of gravitational forces.
Claim 5
Dependent Claim
27 words
A method as defined in claim 1 in which the foreign substance that is removed from the polluted water is a paint, enamel or similar foreign substance.
References Cited (Backward Citations)
US2778499A
Cited
US3249533A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-12 | 1977-05-14 | 1977-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-12 | 1981-05-14 | 1981-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-12 | 1985-05-14 | 1985-11-13 | $7700.00 | Window Closed / Lapsed |