Patent US4541986A successfully refreshed from Google Patents.
US4541986A
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Process for deodorizing sludge
Assignee: Evonik Operations GmbH
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Filing: 1984-03-16
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Granted: 1985-09-17
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Expires: 2004-03-16
Abstract
Abstract Sludge, especially sewage sludge is deodorized, particularly to obtain the biomass by treating the waste water sludge (pollution sludge) with an active oxygen developing compound at 5° to 40°C.
Inventors
- 👤 Heinrich Schwab
- 👤 Werner Kaschke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 00:28
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/72; C02F1/722; C02F1/76; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/916
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
73 words
A process of deodorizing a waste water sludge containing fermentation causing microorganism according to claim 17 consisting essentially of treating the waste water sludge at a temperature of 5 to 40° C. and a pH of 5.0 to 7.0 with an active oxygen developing compound selected from the group consisting of alkali metal chlorites and alkaline earth metal chlorites in an amount sufficient to temporarily delay the fermentation process caused by such microorganisms.
Claim 2
Dependent Claim
17 words
The process of claim 1 wherein the active oxygen developing compound is sodium chlorite or potassium chlorite.
Claim 3
Dependent Claim
14 words
The process of claim 2 wherein the active oxygen developing compound is sodium chlorite.
Claim 4
Dependent Claim
13 words
The process of claim 3 wherein the sludge is treated at 5-25° C.
Claim 5
Dependent Claim
19 words
The process of claim 4 wherein the sludge treatment is carried out at a pH of 5.0 to 6.8.
Claim 6
Dependent Claim
15 words
The process of claim 2 wherein the sludge treatment is carried out at 5-25° C.
Claim 7
Dependent Claim
19 words
The process of claim 6 wherein the sludge treatment is carried out at a pH of 5.0 to 6.8.
Claim 8
Dependent Claim
26 words
A process according to claim 2 wherein the waste water sludge contains hydrogen sulfide and the deodorization includes the elimination of odors caused by hydrogen sulfide.
Claim 9
Dependent Claim
14 words
The process of claim 1 wherein the active oxygen developing compound is calcium chlorite.
Claim 10
Dependent Claim
31 words
The process of claim 1 wherein the amount of oxygen developing compound is equivalent to 50 to 120 kg of 24 weight % sodium chlorite solution per 100 m 3 sludge.
Claim 11
Dependent Claim
14 words
The process of claim 10 wherein the active oxygen developing compound is sodium chlorite.
Claim 12
Dependent Claim
25 words
The process of claim 11 wherein the amount of sodium chlorite is 12 to 28.8 kg of sodium chlorite per 100 m 3 of sludge.
Claim 13
Dependent Claim
25 words
The process of claim 12 wherein the amount of sodium chlorite is 12 to 16.8 kg of sodium chlorite per 100 m 3 of sludge.
Claim 14
Dependent Claim
33 words
A process according to claim 1 wherein there are present in the sludge anearobic fermentation causing nicroorganisms and the active oxygen developing compound is employed in an amount sufficient to stop anaerobic fermentation.
Claim 15
Dependent Claim
26 words
A process according to claim 1 wherein the waste water sludge contains hydrogen sulfide and the deodorization includes the elimination of odors caused by hydrogen sulfide.
Claim 16
Dependent Claim
75 words
A process of deodorizing a waste water sludge containing fermentation causing microorganisms comprising treating the waste water sludge at a temperature of 5 to 40° C. and a pH of 5.0 to 7.0 with an active oxygen developing compound selected from the group consisting of alkali metal chlorites and alkaline earth metal chlorites in an amount sufficient to temporarily delay the fermentation process caused by such microorganisms but not to kill all of the organisms.
Claim 17
Dependent Claim
75 words
A process of deodorizing a waste water sludge containing fermentation causing microorganisms comprising treating the waste water sludge at a temperature of 5 to 40° C. and a pH of 5.0 to 7.0 with an active oxygen developing compound selected from the group consisting of alkali metal chlorites and alkaline earth metal chlorites in an amount sufficient to temporarily delay the fermentation process caused by such microorganisms but not to kill all of the organisms.
Claim 18
Dependent Claim
17 words
The process of claim 16 wherein the active oxygen developing compound is sodium chlorite or potassium chlorite.
Claim 19
Dependent Claim
62 words
A process according to claim 10 consisting of treating the waste water sludge at a temperature of 5 to 40° C. and a pH of 5.0 to 7.0 with an active oxygen developing compound selected from the group consisting of alkali metal chlorites and alkaline earth metal chlorites in an amount sufficient to temporarily delay the fermentation process caused by such microorganisms.
Claim 20
Dependent Claim
18 words
A process according to claim 18 wherein the active oxygen developing compound is sodium chlorite or potassium chlorite.
Claim 21
Dependent Claim
26 words
A process according to claim 19 wherein the waste water sludge contains hydrogen sulfide and the deodorization includes the elimination of odors caused by hydrogen sulfide.
References Cited (Backward Citations)
US3361528A
Cited
US3705098A
Cited
US3867509A
Cited
JPS5147585A
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US4108771A
Cited
US4157300A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-16 | 1989-03-18 | 1989-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-16 | 1993-03-18 | 1993-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-16 | 1997-03-18 | 1997-09-17 | $7700.00 | Window Closed / Lapsed |