US4190528A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for biological purification of waste water
Assignee: Stamicarbon BV
•
Filing: 1978-06-20
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Granted: 1980-02-26
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Expires: 1998-06-20
Abstract
Abstract Process for the biological purification of waste water in which a suspension of the surplus sludge formed during the purification is hydrolyzed in a basic medium and at elevated temperatures.
Inventors
- 👤 Bernardus H. N. Dassen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:00
CPC Classifications
C; C02; C02F; C02F11/00; C02F11/18; A; A23; A23J; A23J1/00; A23J1/001; Y; Y10; Y10S; Y10S426/00; Y10S426/807
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
118 words
Process for biological purification of waste water, in which a suspension of the activated sludge formed during the purification is hydrolyzed in a basic medium and at an elevated temperature, said process being conducted by giving the suspension a pH of between about 8 and about 11 and carrying out the hydrolysis in the presence of a volatile base selected from the group consisting of ammonia and ammonium carbonate at a temperature of between about 90° C. and about 300° C., to obtain a hydrolysate containing at least one of naturally occurring amino acids or oligopeptides, separating the hydrolysate from the suspension, expelling said volatile base from said hydrolysate, and returning said volatile base to adjust said pH.
Claim 2
Dependent Claim
118 words
Process for biological purification of waste water, in which a suspension of the activated sludge formed during the purification is hydrolyzed in a basic medium and at an elevated temperature, said process being conducted by giving the suspension a pH of between about 8 and about 11 and carrying out the hydrolysis in the presence of a volatile base selected from the group consisting of ammonia and ammonium carbonate at a temperature of between about 90° C. and about 300° C., to obtain a hydrolysate containing at least one of naturally occurring amino acids or oligopeptides, separating the hydrolysate from the suspension, expelling said volatile base from said hydrolysate, and returning said volatile base to adjust said pH.
Claim 3
Dependent Claim
21 words
Process of claim 1 wherein the hydrolysis is carried out at a temperature of between about 90° and about 200° C.
Claim 4
Dependent Claim
16 words
Process of claim 1, wherein one or more N compounds are recovered from the hydrolysate formed.
Claim 5
Dependent Claim
16 words
Process of claim 3, wherein the hydrolysate formed is fully or partly processed to cattle feed.
Claim 6
Dependent Claim
22 words
Process of claim 4, wherein the hydrolysate formed is returned to the biological purification after the solid matter has been separated off.
Claim 7
Dependent Claim
20 words
Process of claim 4, wherein the volatile base is stripped from the hydrolysate with an inert gas or gas mixture.
Claim 8
Dependent Claim
19 words
Process of claim 1, 3, or 4 wherein the process is carried out under conditions at which deamination occurs.
Claim 9
Dependent Claim
35 words
Process of claim 7, wherein the hydrolysis is carried out at a temperature of between about 150° and about 300° C. and an NH 3 concentration of between about 4 N and about 14 N.
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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) | 1983-02-25 | 1983-08-27 | 1984-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-02-25 | 1987-08-27 | 1988-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-02-25 | 1991-08-27 | 1992-02-26 | $7700.00 | Window Closed / Lapsed |