US4085887A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Centrifuge for draining off sewage sludge
Assignee: Individual
•
Filing: 1976-04-12
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Granted: 1978-04-25
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Expires: 1996-04-12
Abstract
Abstract Decanting centrifuge with an inner drum and an outer drum coaxial with the inner drum, each having a helical scraper rotating with a number of revolutions slightly differing from that of the drums, in which sewage sludge to be dewatered is fed to the inner drum and therefrom after initial separation through common passages is transported to the outer drum, in which separated sludge by means of the helical scraper is transported to a discharge at one end and liquid is removed through reject outlets at the other.
Inventors
- 👤 Bye-Jorgensen Jorgen Steen 4
- 👤 Gunnar Valdemar Hartvig Larsen
- 👤 Poul Henrik Vermehren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:16
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/38; C02F1/385; B; B04; B04B; B04B1/00; B04B1/20
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
263 words
In a centrifuge for separating solids, such as sewage sludge, from liquid in which the solids are initially suspended, inner rotary drum and scraper means for receiving the liquid with the solids suspended therein and for subjecting them to an initial separating stage, outer rotary drum and scraper means coaxially surrounding said inner rotary drum and scraper means for subjecting the liquids and solids to a final separating stage, said outer rotary drum and scraper means including a drum formed at opposed end regions with outlets for the separated solids and liquid, respectively, and passage means operatively connected with both of said inner and outer rotary drum and scraper means for providing a common path of travel for the liquid and solids flowing from said inner rotary drum and scraper means subsequent to the initial separating stage to said outer rotary drum and scraper means to be subjected to the final separating stage, said inner rotary drum and scraper means initially receiving the liquids and solids suspended therein at one end region of said inner rotary drum and scraper means and feeding the liquids and solids during the initial separating stage toward an opposite end region of said inner rotary drum and scraper means, said passage means communicating with said inner rotary drum and scraper means at said opposite end region thereof, and said liquid outlet of said drum of said outer rotary drum and scraper means communicating primarily only with said outer rotary drum and scraper means for receiving liquid only after the liquid has been subjected to said final separating stage.
Claim 2
Dependent Claim
263 words
In a centrifuge for separating solids, such as sewage sludge, from liquid in which the solids are initially suspended, inner rotary drum and scraper means for receiving the liquid with the solids suspended therein and for subjecting them to an initial separating stage, outer rotary drum and scraper means coaxially surrounding said inner rotary drum and scraper means for subjecting the liquids and solids to a final separating stage, said outer rotary drum and scraper means including a drum formed at opposed end regions with outlets for the separated solids and liquid, respectively, and passage means operatively connected with both of said inner and outer rotary drum and scraper means for providing a common path of travel for the liquid and solids flowing from said inner rotary drum and scraper means subsequent to the initial separating stage to said outer rotary drum and scraper means to be subjected to the final separating stage, said inner rotary drum and scraper means initially receiving the liquids and solids suspended therein at one end region of said inner rotary drum and scraper means and feeding the liquids and solids during the initial separating stage toward an opposite end region of said inner rotary drum and scraper means, said passage means communicating with said inner rotary drum and scraper means at said opposite end region thereof, and said liquid outlet of said drum of said outer rotary drum and scraper means communicating primarily only with said outer rotary drum and scraper means for receiving liquid only after the liquid has been subjected to said final separating stage.
Claim 3
Dependent Claim
100 words
The combination of claim 1 and wherein said passage means is also situated at an end region of said outer rotary drum and scraper means for delivering the liquid and solids subsequent to the initial separating stage to the latter end region of said outer rotary drum and scraper means, said outer rotary drum and scraper means feeding the solids from said end region thereof toward an opposite end region where said outlet for the solids is situated while the liquid separated at the second stage is free to flow in an opposite direction to the outlet for the liquid.
Claim 4
Dependent Claim
23 words
The combination of claim 2 and wherein said inner and outer rotary drum and scraper means respectively feed the solids in opposite directions.
Claim 5
Dependent Claim
45 words
The combination of claim 3 and wherein said outer rotary drum and scraper means has in its interior an annular duct for directing the liquid separated at the second stage toward the liquid outlet of said drum of said outer rotary drum and scraper means.
Claim 6
Dependent Claim
273 words
In a centrifuge for separating solids, such as sewage sludge, from liquid in which the solids are initially suspended, inner rotary drum and scraper means for receiving the liquid with the solids suspended therein and for subjecting them to an initial separating stage, outer rotary drum and scraper means coaxially surrounding said inner rotary drum and scraper means for subjecting the liquids and solids to a final separating stage, said outer rotary drum and scraper means including a drum formed at opposed end regions with outlets for the separated solids and liquid, respectively, and passage means operatively connected with both of said inner and outer rotary drum and scraper means for providing a common path of travel for the liquid and solids flowing from said inner rotary drum and scraper means subsequent to the initial separating stage to said outer rotary drum and scraper means to be subjected to the final separating stage, said inner rotary drum and scraper means initially receiving the liquids and solids suspended therein at one end region of said inner rotary drum and scraper means and feeding the liquids and solids during the initial separating stage toward an opposite end region of said inner rotary drum and scraper means, said passage means communicating with said inner rotary drum and scraper means at said opposite end region thereof, said passage means being situated at an intermediate region of said outer rotary drum and scraper means while said outer rotary drum and scraper means feeds the solids and liquid during the final separating stage in opposite directions from said intermediate region respectively toward the outlets for the solids and liquid.
Claim 7
Dependent Claim
273 words
In a centrifuge for separating solids, such as sewage sludge, from liquid in which the solids are initially suspended, inner rotary drum and scraper means for receiving the liquid with the solids suspended therein and for subjecting them to an initial separating stage, outer rotary drum and scraper means coaxially surrounding said inner rotary drum and scraper means for subjecting the liquids and solids to a final separating stage, said outer rotary drum and scraper means including a drum formed at opposed end regions with outlets for the separated solids and liquid, respectively, and passage means operatively connected with both of said inner and outer rotary drum and scraper means for providing a common path of travel for the liquid and solids flowing from said inner rotary drum and scraper means subsequent to the initial separating stage to said outer rotary drum and scraper means to be subjected to the final separating stage, said inner rotary drum and scraper means initially receiving the liquids and solids suspended therein at one end region of said inner rotary drum and scraper means and feeding the liquids and solids during the initial separating stage toward an opposite end region of said inner rotary drum and scraper means, said passage means communicating with said inner rotary drum and scraper means at said opposite end region thereof, said passage means being situated at an intermediate region of said outer rotary drum and scraper means while said outer rotary drum and scraper means feeds the solids and liquid during the final separating stage in opposite directions from said intermediate region respectively toward the outlets for the solids and liquid.
Claim 8
Dependent Claim
24 words
The combination of claim 5 and wherein said inner and outer rotary drum and scraper means both feed the solids in the same direction.
Claim 9
Dependent Claim
48 words
The combination of claim 6 and wherein said inner rotary drum and scraper means receives the liquids and solids to be separated at an end region of said inner rotary drum and scraper means which is adjacent the liquid outlet of said outer rotary drum and scraper means.
Claim 10
Dependent Claim
76 words
The combination of claim 7 and wherein said outer rotary drum and scraper means includes a scraper which extends at least through a substantial distance from said intermediate region of said rotary drum and scraper means toward said liquid outlet for separating from the liquid flowing toward the latter outlet solids which are added to the solids travelling from said intermediate region of said outer rotary drum and scraper means to the outlet for the solids.
References Cited (Backward Citations)
US1064184A
Cited
US1806241A
Cited
US2734681A
Cited
US2711854A
Cited
DE1027140B
Cited
DE1082192B
Cited
US3782623A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-04-24 | 1981-10-24 | 1982-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-24 | 1985-10-24 | 1986-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-24 | 1989-10-24 | 1990-04-25 | $7700.00 | Window Closed / Lapsed |