Patent US3697420A successfully refreshed from Google Patents.
US3697420A
Expired / Lapsed
US
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Method and apparatus for treatment of aqueous liquor
Assignee: Individual
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Filing: 1968-03-19
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Granted: 1972-10-10
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Expires: 1988-03-19
Abstract
Abstract SEWAGE TREATMENT METHODS AND APPARATUS ARE DISCLOSED INCLUDING THOSE RELATING TO CATALYTIC OXIDATION, DIGESTION UNDER THE INFLUENCE OF MAGNETIC FIELDS, THE USE OF WEIGHTING AGENTS WHICH, PREFERABLY, ARE MAGNETICALLY SUSCEPTIBLE, AND MAGNETIC DENSIFICATION. MAGNETIC DENSIFICATION IS ACHIEVED BY ADDING CATIONIC POLYELECTROLYTIC COAGULANTS AND MAGNETIC WEIGHTING AGENTS TO SEWAGE AND DENSIFYING THE COAGULATED SOLIDS UNDER THE INFLUENCE OF A MAGNETIC FIELD WHICH MAY BE EITHER UNIFORM OR NONUNIFORM, THUS PRODUCING A CLARIFIED EFFLUENT.
Inventors
- 👤 Donald Stapf Blaisdell
- 👤 Ruth Elizabeth Barry Klaas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:27
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/52; C02F1/54; B; B01; B01D; B01D21/00; B01D21/0009; B01D21/01; B03; B03C; B03C1/00; B03C1/005; B03C1/01; C02F1/48; C02F1/488
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-10 | 1976-04-10 | 1976-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-10 | 1980-04-10 | 1980-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-10 | 1984-04-10 | 1984-10-10 | $7700.00 | Window Closed / Lapsed |