US2772234A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sludge treatment
Assignee: PROCESS ENGINEERS Inc
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Filing: 1953-05-14
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Granted: 1956-11-27
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Expires: 1973-05-14
Abstract
No abstract record available.
Inventors
- 👤 Earl M Kelly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:03
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/24; B; B03; B03D; B03D1/00; B03D1/02; B03D1/028; B03D1/14; B03D1/1431; C02F3/00; C02F3/30
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
155 words
IN THE TREATMENT OF SEWAGE CONTAINING SOLIDS SUSPENDED IN LIQUID INVOLVING INTRODUCING THE SEWAGE INTO A POOL IN WHICH THE SOLIDS WOULD SETTLE TO THE BOTTOM TO PRODUCE A SLUDGE OF MAXIMUM DENSITY UNDER QUIESCENT CONDITIONS, AND THE WITHDRAWAL OF SLUDGE FROM THE BOTTOM OF THE POOL, THE IMPROVEMENT WHICH COMPRISES INTRODUCING THE SEWAGE INTO THE POOL AND WITHDRAWING THE SLUDGE FROM THE BOTTOM OF THE POOL AT SUCH FAST RATES THAT THE WITHDRAWN SLUDGE CONTAINS LESS THAN 5% SOLIDS BY WEIGHT AND IS SUBSTANTIALLY LESS THAN MAXIMUM IN DENSITY, DISSOLVING GAS IN THE WITHDRAWN SLUDGE UNDER PRESSURE AND THUS CHARGE IT, INTRODUCING THE CHARGED PRESSURE AND INTO A SECOND POOL MAINTAINED AT A REDUCED PRESSURE SO THAT AT LEAST SOME OF THE GAS COMES OUT OF SOLUTION IN THE SECOND POOLS AS BUBBLES AND RAISES SOLIDS IN THE SECOND POOL TO FROM A SCUM ON ITS SURFACE, AND SKIMMING THE SCUM FROM THE SURFACE.
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) | 1959-11-27 | 1960-05-28 | 1960-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-11-27 | 1964-05-28 | 1964-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-11-27 | 1968-05-28 | 1968-11-27 | $7700.00 | Window Closed / Lapsed |