US4209390A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for biological denitrification of effluents
Assignee: Produits Chimiques Ugine Kuhlmann
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Filing: 1978-07-06
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Granted: 1980-06-24
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Expires: 1998-07-06
Abstract
Abstract The present invention is directed to a process for biological denitrification of effluents, containing up to 10 g/l of nitric nitrogen, which comprises using an active denitrification support made of selected high performance denitrifying bacteria fixed on a neutral support.
Inventors
- 👤 Bruno Cabane
- 👤 Joel Vergnault
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:34
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/28; C02F3/2806; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/903; Y10S435/00; Y10S435/813; Y10S435/8215; Y10S435/822; Y10S435/874
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
85 words
A process for the biological denitrification of effluents containing up to 10 g/l of nitric nitrogen comprising: (a) selecting strains of bacteria having a denitrifying activity; (b) preculturing the selected strains in a denitrification medium containing a substrate of calcium nitrate under anaerobiosis conditions in the presence of a carbonaceous material to form in situ an active denitrification support comprising denitrifying bacteria and grains of calcium carbonate; and (c) contacting the active denitrification support with the effluents containing nitric nitrogen which are to be denitrified.
Claim 2
Dependent Claim
85 words
A process for the biological denitrification of effluents containing up to 10 g/l of nitric nitrogen comprising: (a) selecting strains of bacteria having a denitrifying activity; (b) preculturing the selected strains in a denitrification medium containing a substrate of calcium nitrate under anaerobiosis conditions in the presence of a carbonaceous material to form in situ an active denitrification support comprising denitrifying bacteria and grains of calcium carbonate; and (c) contacting the active denitrification support with the effluents containing nitric nitrogen which are to be denitrified.
Claim 3
Dependent Claim
53 words
The process of claim 1 wherein the strains of bacteria having a denitrifying activity are selected by successive subcultures in a liquid medium comprising components selected as a function of the organic carbon substrate used in the denitrification and as a function of the type and concentration of nitric nitrogen in the effluents.
Claim 4
Dependent Claim
29 words
The process of claim 2 wherein yeast extract is added to the liquid medium in which the selected strains of bacteria having denitrifying activity are enriched by successive subcultures.
Claim 5
Dependent Claim
30 words
The process of claim 1 wherein the active denitrification support comprises a central nucleus on which are fixed the denitrifying bacteria and the calcium carbonate formed by the denitrification reaction.
Claim 6
Dependent Claim
20 words
The process of claim 4 wherein the central nucleus is selected from the group comprising charcoal and calcium carbonate grains.
Claim 7
Dependent Claim
25 words
The process of claim 1 wherein the rate of denitrification is increased by the addition of a solution of trace elements to the denitrification medium.
Claim 8
Dependent Claim
12 words
The process of claim 1 wherein the denitrification occurs at 30° C.
Claim 9
Dependent Claim
15 words
The process of claim 1 wherein the effluent to be denitrified is an industrial effluent.
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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) | 1983-06-24 | 1983-12-24 | 1984-06-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-06-24 | 1987-12-24 | 1988-06-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-06-24 | 1991-12-24 | 1992-06-24 | $7700.00 | Window Closed / Lapsed |