US3409546A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for dewatering sewage sludge with a mixture of polymers
Assignee: Dow Chemical Co
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Filing: 1966-06-01
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Granted: 1968-11-05
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Expires: 1986-06-01
Abstract
No abstract record available.
Inventors
- 👤 Mogelnicki Stanley
- 👤 Eugene M Gatza
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:19
CPC Classifications
C; C02; C02F; C02F11/00; C02F11/12; B; B01; B01J; B01J20/00; B01J20/22; C02F1/00; C02F1/52; C02F1/54; C08; C08L; C08L79/00; C08L79/02
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
78 words
A METHOD FOR DEWATERING A RAW SEWAGE SLUDGE WHICH COMPRISES MIXING THE SLUDGE AN AQUEOUS SOLUTION OF A WATER-SOLUBLE, AMINO-CONDENSATION POLYMER AND A HIGH MOLECULAR WEIGHT, WATER-SOLUBLE, CATIONIC, VINYL-ADDITION POLYMER, THE AMOUNT OF VINYL-ADDITION POLYMER PRESENT IN THE SOLUTION BEING FROM ABOUT 0.02 TO ABOUT 0.3 PART THEREOF FOR EACH PART BY WEIGHT OF CONDENSATION POLYMER; THE AMOUNT OF AQUEOUS POLYMER SOLUTION APPLIED BEING SUFFICIENT TO CONDITION THE SLUDGE FOR DEWATERING AND SEPARATING WATER FROM THE CONDITIONED SLUDGE.
Claim 2
Independent Claim
78 words
A METHOD FOR DEWATERING A RAW SEWAGE SLUDGE WHICH COMPRISES MIXING THE SLUDGE AN AQUEOUS SOLUTION OF A WATER-SOLUBLE, AMINO-CONDENSATION POLYMER AND A HIGH MOLECULAR WEIGHT, WATER-SOLUBLE, CATIONIC, VINYL-ADDITION POLYMER, THE AMOUNT OF VINYL-ADDITION POLYMER PRESENT IN THE SOLUTION BEING FROM ABOUT 0.02 TO ABOUT 0.3 PART THEREOF FOR EACH PART BY WEIGHT OF CONDENSATION POLYMER; THE AMOUNT OF AQUEOUS POLYMER SOLUTION APPLIED BEING SUFFICIENT TO CONDITION THE SLUDGE FOR DEWATERING AND SEPARATING WATER FROM THE CONDITIONED SLUDGE.
References Cited (Backward Citations)
US3023162A
Cited
US3252900A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-11-05 | 1972-05-06 | 1972-11-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-11-05 | 1976-05-06 | 1976-11-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-11-05 | 1980-05-06 | 1980-11-05 | $7700.00 | Window Closed / Lapsed |