US3242071A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Intermittent stirring apparatus for digesters and method of operating a digester
Assignee: Walker Process Equipment Inc
•
Filing: 1961-11-13
•
Granted: 1966-03-22
•
Expires: 1981-11-13
Abstract
No abstract record available.
Inventors
- 👤 Walker James Donald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:18
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/28; C02F3/2866; C02F3/2873; Y; Y10; Y10S; Y10S210/00; Y10S210/918; Y10S210/921; Y10S261/00; Y10S261/70
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
185 words
THE METHOD OF OPERATING A DIGESTER: IN WHICH THE DIGESTER COMPRISES A TANK, MEANS FOR FEEDING TO THE TANK SEWAGE SLUDGE TO BE DIGESTED THEREIN, STIRRING MEANS FOR VIGOROUSLY STIRRING A LARGE BODY OF SLUDGE WITHIN THE TANK, AND DRAW-OFF MEANS HAVING ITS OPENING FOR OUTFLOW FROM THE MAIN SPACE OF THE TANK POSITIONED TO DRAW SLUDGE FROM A DRAWOFF AREA SUBJECT TO THE STIRRING ACTION OF THE STIRRING MEANS BUT LOCATED AT A POINT TO WHICH THE FRESHLY FED SLUDGE TO BE DIGESTED IS NOT LIKELY TO MOVE BY GRAVIMETRIC INFLUENCES WHEN THE STIRRING MEANS IS NOT OPERATING; SAID METHOD COMPRISING OPERATING SAID STIRRING MEANS TO CAUSE THOROUGH INTERMIXING OF THE SLUDGE FED TO BE TREATED WITH SLUDGE WHICH HAS BEEN UNDERGOING DIGESTION, FOR SEEDING THE SLUDGE TO BE TREATED; PERIODICALLY CAUSING SLUDGE FROM THE TANK TO FLOW THROUGH SAID DRAW-OFF MEANS BUT AT INTERVENING PERIODS MAINTAINING THE SLUDGE DRAW-OFF MEANS IDLE; AND CONSISTENTLY DISCONTINUING THE OPERATION OF THE STIRRING MEANS BEFORE AND DURING THE OUTFLOW OF SLUDGE THROUGH SAID DRAW-OFF MEANS TO AVOID THE MOVING OF SLUDGE FRESHLY FED TO SAID DRAW-OFF AREA.
Claim 2
Independent Claim
185 words
THE METHOD OF OPERATING A DIGESTER: IN WHICH THE DIGESTER COMPRISES A TANK, MEANS FOR FEEDING TO THE TANK SEWAGE SLUDGE TO BE DIGESTED THEREIN, STIRRING MEANS FOR VIGOROUSLY STIRRING A LARGE BODY OF SLUDGE WITHIN THE TANK, AND DRAW-OFF MEANS HAVING ITS OPENING FOR OUTFLOW FROM THE MAIN SPACE OF THE TANK POSITIONED TO DRAW SLUDGE FROM A DRAWOFF AREA SUBJECT TO THE STIRRING ACTION OF THE STIRRING MEANS BUT LOCATED AT A POINT TO WHICH THE FRESHLY FED SLUDGE TO BE DIGESTED IS NOT LIKELY TO MOVE BY GRAVIMETRIC INFLUENCES WHEN THE STIRRING MEANS IS NOT OPERATING; SAID METHOD COMPRISING OPERATING SAID STIRRING MEANS TO CAUSE THOROUGH INTERMIXING OF THE SLUDGE FED TO BE TREATED WITH SLUDGE WHICH HAS BEEN UNDERGOING DIGESTION, FOR SEEDING THE SLUDGE TO BE TREATED; PERIODICALLY CAUSING SLUDGE FROM THE TANK TO FLOW THROUGH SAID DRAW-OFF MEANS BUT AT INTERVENING PERIODS MAINTAINING THE SLUDGE DRAW-OFF MEANS IDLE; AND CONSISTENTLY DISCONTINUING THE OPERATION OF THE STIRRING MEANS BEFORE AND DURING THE OUTFLOW OF SLUDGE THROUGH SAID DRAW-OFF MEANS TO AVOID THE MOVING OF SLUDGE FRESHLY FED TO SAID DRAW-OFF AREA.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-03-21 | 1969-09-20 | 1970-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-03-21 | 1973-09-20 | 1974-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-03-21 | 1977-09-20 | 1978-03-22 | $7700.00 | Window Closed / Lapsed |