Patent US3649529A successfully refreshed from Google Patents.
US3649529A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Complete mix sewage treatment system
Assignee: Chicago Bridge and Iron Co
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Filing: 1969-01-23
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Granted: 1972-03-14
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Expires: 1989-01-23
Abstract
Abstract IN AN ACTIVATED SLUDGE SEWAGE AERATION SYSTEM, AERATION, MIXING, AND UNIFORMITY THROUGHOUT A TANK, ARE IMPROVED BY LIBERATING AIR ALONG LINES POSITIONED TO GENERATE IN THE CONTENTS OF THE TANK, ROLLS HAVING THEIR AXES ON A BIAS, THAT IS, NEITHER PARALLEL TO NOR PERPENDICULAR TO THE TANK WALLS OR TO THE "GENERAL DIRECTION OF FLOW" OF THE PROCESSED LIQUID. PREFERABLY USING A TANK THUS MIXED, THE KNOWN ADVANTAGES OF "COMPLETE MIXING" ARE ACHIEVED, AND MAY BE ENHANCED, BY FEEDING AN INTIMATE MIXTURE OF RAW SEWAGE AND RETURN ACTIVATED SLUDGE TO THE TANK AT FEED POINTS SO SCATTERED THAT NO PART OF THE TANK IS FAR FROM A FEED POINT.
Inventors
- 👤 James Donald Walker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:08
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/02; C02F3/12; C02F3/20; Y; Y02; Y02W; Y02W10/00; Y02W10/10
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) | 1975-03-14 | 1975-09-13 | 1976-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-14 | 1979-09-13 | 1980-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-14 | 1983-09-13 | 1984-03-14 | $7700.00 | Window Closed / Lapsed |