Patent US3926796A successfully refreshed from Google Patents.
US3926796A
Expired / Lapsed
US
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Preparation of activated sludge and treatment of waste water therewith
Assignee: Mitsubishi Chemical Corp
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Filing: 1974-09-23
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Granted: 1975-12-16
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Expires: 1994-09-23
Abstract
Abstract Preparation of an activated sludge capable of assimilating polyvinyl alcohol resins included in waste water by subjecting an ordinary activated sludge to acclimation in an aqueous solution in the presence of specific amount of polyvinyl alcohol resins and a specific kind of nutrients. In acclimation, the amount of the polyvinyl alcohol resins is increased stepwise from less amount to more amount every 85 % or more drop of the chemical oxygen demand of the aqueous solution. The acclimation can be completed in such a short period as 4 to 20 days. The waste water effluent including polyvinyl alcohol resins can be treated by passing through said activated sludge with a high efficiency.
Inventors
- 👤 Yukio Fujita
- 👤 Iwao Kawasaki
- 👤 Hideo Nishikawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 12:26
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/02; C02F3/12; C02F3/1205; C02F3/1231; C02F3/34; Y; Y02; Y02W; Y02W10/00; Y02W10/10; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/911
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
201 words
A PROCESS FOR THE PREPARATION OF AN ACTIVATED SLUDGE CAPABLE OF ASSIMILATING A SOLUTON OF POLYVINYL ALCOHOL RESINS WHICH COMPRISES SUBJECTING AN ORDINARY ACTIVATED SLUDGE TO ACCLIMATION UNDER CONDITIONS OF 15* TO 35*C. IN TEMPERATURE, 7.0 TO 8.5 IN PH AND 1 TO 6 P.P.M. IN TEMPERATURE, 15 HOURS WITH AGITATION IN A PREPARED BY DISSOLVING AT LEAST ONE MEMBER SELECTED FROM THE GROUP CONSISTING OF POLYVINYL ALCOHOL HAVING NOT LESS THAN 70% BY MOLE OF A DEGREE OF HYDROLYSIS, WATER-SOLUBLEE ACETALIZED POLYVINYL ALCOHOL, WATER-SOLUBLE URETHANATED POLYVINYL ALCOHOL, WATER-SOLUBLE HYDROLYZED COPOLYMER OF VINYL ACETATE AND ETHYLENE OR PROPYLENE WATER-SOLUBLE HYDROLYZED COPOLYMER OF VINYL ACETATE AND MALEIC ACID, CROTONIC ACID, ACRYLIC ACID OR ACRYLIC AMIDE, PARTIALLY ACETALIZATED ONE OF THE ABOVE HYDROLYZED COPOLYMERS IN AN THANATED ONE OF THE ABOVE HYDROLYZED COPOLYMER IN AN AMOUNT OF 0.005 TO 0.6 KG./KG/ MIXED LIQUOR SUSPENDED SOLID/DAY AND AT LEAST ONE SOLUTION SELECTED FROM THE GROUP CONSISTING OF ACETIC ACID, PROPIONIC ACID, POTASSIUM, SODIUM, CALCIUM OR AMMONIUM SALTS THEREOF, METHYL, ETHYL, PROPYL OR BUTYLESTERS THEREOF, AMIDES THEREOF, MALIC ACID, CITRIC ACID FUMARIC ACID, OXALIC ACID AND LACTIC ACID, IN THE RANGE OF BIOCHEMICAL OXYGEN DEMAND LOADING OF 0.05 TO 0.3 KG./KG. MIXED LIQUOR SUSPENDED SOLID/DAY.
Claim 2
Dependent Claim
201 words
A PROCESS FOR THE PREPARATION OF AN ACTIVATED SLUDGE CAPABLE OF ASSIMILATING A SOLUTON OF POLYVINYL ALCOHOL RESINS WHICH COMPRISES SUBJECTING AN ORDINARY ACTIVATED SLUDGE TO ACCLIMATION UNDER CONDITIONS OF 15* TO 35*C. IN TEMPERATURE, 7.0 TO 8.5 IN PH AND 1 TO 6 P.P.M. IN TEMPERATURE, 15 HOURS WITH AGITATION IN A PREPARED BY DISSOLVING AT LEAST ONE MEMBER SELECTED FROM THE GROUP CONSISTING OF POLYVINYL ALCOHOL HAVING NOT LESS THAN 70% BY MOLE OF A DEGREE OF HYDROLYSIS, WATER-SOLUBLEE ACETALIZED POLYVINYL ALCOHOL, WATER-SOLUBLE URETHANATED POLYVINYL ALCOHOL, WATER-SOLUBLE HYDROLYZED COPOLYMER OF VINYL ACETATE AND ETHYLENE OR PROPYLENE WATER-SOLUBLE HYDROLYZED COPOLYMER OF VINYL ACETATE AND MALEIC ACID, CROTONIC ACID, ACRYLIC ACID OR ACRYLIC AMIDE, PARTIALLY ACETALIZATED ONE OF THE ABOVE HYDROLYZED COPOLYMERS IN AN THANATED ONE OF THE ABOVE HYDROLYZED COPOLYMER IN AN AMOUNT OF 0.005 TO 0.6 KG./KG/ MIXED LIQUOR SUSPENDED SOLID/DAY AND AT LEAST ONE SOLUTION SELECTED FROM THE GROUP CONSISTING OF ACETIC ACID, PROPIONIC ACID, POTASSIUM, SODIUM, CALCIUM OR AMMONIUM SALTS THEREOF, METHYL, ETHYL, PROPYL OR BUTYLESTERS THEREOF, AMIDES THEREOF, MALIC ACID, CITRIC ACID FUMARIC ACID, OXALIC ACID AND LACTIC ACID, IN THE RANGE OF BIOCHEMICAL OXYGEN DEMAND LOADING OF 0.05 TO 0.3 KG./KG. MIXED LIQUOR SUSPENDED SOLID/DAY.
Claim 3
Dependent Claim
47 words
The process of claim 1, wherein the amount of said polyvinyl alcohol resin is increased stepwise from less amount to more amount within the range of 0.005 to 0.6 kg./kg. mixed liquor suspended solid/day every 85% or more drop of chemical oxygen demand of the aqueous solution.
Claim 4
Dependent Claim
25 words
The process of claim 1, wherein said nutrient is a member selected from the group consisting of acetic acid, potassium acetate, sodium acetate, ammonium acetate.
Claim 5
Dependent Claim
17 words
The process of claim 1, wherein said aqueous solution is a waste water containing polyvinyl alcohol resins.
Claim 6
Dependent Claim
28 words
A process for treating a waste water effluent containing a polyvinyl alcohol resin which comprises passing the waste water through the activated sludge acclimated according to claim 1.
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) | 1978-12-15 | 1979-06-16 | 1979-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-15 | 1983-06-16 | 1983-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-15 | 1987-06-16 | 1987-12-16 | $7700.00 | Window Closed / Lapsed |