US4256573A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for biological treatment of waste water in downflow operation
Assignee: Chiyoda Corp
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Filing: 1979-02-14
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Granted: 1981-03-17
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Expires: 1999-02-14
Abstract
Abstract This invention relates to biological treatment of waste water using a carrier floatable on water, and more particularly to a novel process for treatment of waste water utilizing a fluidized bed which is formed by supplying waste water in a downflow operation. The process for treatment of waste water of this invention is applicable to both anaerobic and aerobic biological treatment. A good example of the former anaerobic biological treatment to which this invention is applicable is the process wherein the nitrate or nitrite nitrogen which is one of the nitrogen compounds that are at present believed to be one cause of the eutrophication in rivers, lakes, seas, etc. is treated with denitrifying bacteria in an anaerobic condition to be released in the form of nitrogen gas, and the typical of the latter aerobic treatment is the practice in the utilization of the action of the aerobic bacteria which can oxidize organic substances in sewage, industrial waste waters, etc.
Inventors
- 👤 Chiaki Shimodaira
- 👤 Yoshinori Yushina
- 👤 Hiroshi Kamata
- 👤 Hideo Komatsu
- 👤 Akinori Kurima
- 👤 Osamu Mabu
- 👤 Yoshiharu Tanaka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:22
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/02; C02F3/08; C02F3/085; C02F3/087; B; B01; B01J; B01J8/00; B01J8/18; B01J8/20; B01J8/22; C02F3/28; C02F3/2806; C12; C12M; C12M25/00; C12M25/16; C12M25/18; C12M27/00; C12M27/18; C12M27/24; C12M29/00; C12M29/02; C12M47/00; C12M47/12; Y; Y02; Y02W; Y02W10/00; Y02W10/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
134 words
A process for biological treatment of waste water, comprising: (a) placing particulate material in water within a reactor, said particulate material having an apparent specific gravity smaller than the specific gravity of water making it possible for said particulate material to float on water; (b) allowing microbes to attach to said particulate material which acts as a carrier bed, floating in a substantially immersed state in said water; (c) distributing waste water in a uniform manner, downwardly into said carrier bed to form a fluidized bed of said carrier bed, in such a manner that the biological treatment of said waste water is achieved by contacting said waste water with said microbes while said waste water is passed through said fluidized bed; (d) removing treated water from a lower portion of said fluidized bed.
Claim 2
Dependent Claim
134 words
A process for biological treatment of waste water, comprising: (a) placing particulate material in water within a reactor, said particulate material having an apparent specific gravity smaller than the specific gravity of water making it possible for said particulate material to float on water; (b) allowing microbes to attach to said particulate material which acts as a carrier bed, floating in a substantially immersed state in said water; (c) distributing waste water in a uniform manner, downwardly into said carrier bed to form a fluidized bed of said carrier bed, in such a manner that the biological treatment of said waste water is achieved by contacting said waste water with said microbes while said waste water is passed through said fluidized bed; (d) removing treated water from a lower portion of said fluidized bed.
Claim 3
Dependent Claim
36 words
The process as defined in claim 1, wherein a portion of the treated water which has passed through the bed of said particulate carrier is returned to the top of said bed for reuse in circulation.
Claim 4
Dependent Claim
28 words
The process as defined in claim 1 or 2, wherein the excess microbe attached to the carrier is sloughed off by exerting shearing force upon the microbe-attached carrier.
Claim 5
Dependent Claim
21 words
The process as defined in any of claims 1 or 2, wherein said microbe is anaerobic bacteria or facultative anaerobic bacteria.
Claim 6
Dependent Claim
44 words
The process as defined in any of claims 1 or 2, wherein said microbe is aerobic bacteria, and an additional step is involved in that air or an oxygen-containing gas is supplied to the system from the lower part of said bed of carrier.
Claim 7
Dependent Claim
37 words
The process as defined in any of claims 1 or 2, wherein said particulate material is comprised of foamed plastic particles whose surfaces have been made creasy and of a mixture of lightweight foamed inorganic material therewith.
Claim 8
Dependent Claim
105 words
A process for biological treatment of waste water as in claim 1, further comprising: introducing a gas into a draft tube provided in said reactor from a lower portion of said reactor in order to form an upward flow in said draft tubes in such a manner that carrier particles which are precipitated by the over attaching of microbes are sucked into said draft tubes; stripping away said over attached microbes from said carrier by means of bubbles of said gas blown into said tube and by means of an upward flow of water within said tube; and returning said carrier to said fluidized bed.
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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) | 1984-03-16 | 1984-09-15 | 1985-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-16 | 1988-09-15 | 1989-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-16 | 1992-09-15 | 1993-03-17 | $7700.00 | Window Closed / Lapsed |