Patent US3782623A successfully refreshed from Google Patents.
US3782623A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Decanting centrifuge for draining off water from sewage sludge
Assignee: Kruger AS
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Filing: 1971-06-03
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Granted: 1974-01-01
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Expires: 1991-06-03
Abstract
Abstract Decanting centrifuge for draining off water from sewage sludge, which centrifuge has a rotating bowl and helical walls rotating therein to scrape the sludge towards the end of the bowl to discard it. The rotating bowl has a conical entrance section in which the helical walls are provided, where the progression of the sludge through the conical section is retarded, the conical shape of the section being important to secure a gradual increase of velocity and to reduce any tendency to create turbulence.
Inventors
- 👤 Jorgensen J Bye
- 👤 G Larsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:53
CPC Classifications
B; B04; B04B; B04B1/00; B04B1/20
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
185 words
A decanting centrifuge for drawing off water from sewage sludge comprising: 1. a horizontally disposed rotary drum having a drum cylindrical portion and at least one conically tapered drum end portion disposed adjacent said drum cylindrical portion, said at least one drum end portion providing an opening at one end of said drum of smaller diameter than that of said drum cylindrical portion, said drum cylindrical and said at least one drum end portion forming a continuous light-tight drum surface,; 2. means for feeding sludge into said opening and against the tapered surface of said first drum end portion at its point of smallest diameter; 3. a first helical conveyor in the interior of said rotary drum disposed to rotate separate from said rotary drum, said helical conveyor extending substantially from said at least one drum end portion through said drum cylindrical portion and being pitched to guide the sewage sludge and separated water in a common direction away from said opening; 4. means for removing the separated water from said rotary drum; and 5. means for removing the sewage sludge from said rotary drum.
Claim 2
Dependent Claim
185 words
A decanting centrifuge for drawing off water from sewage sludge comprising: 1. a horizontally disposed rotary drum having a drum cylindrical portion and at least one conically tapered drum end portion disposed adjacent said drum cylindrical portion, said at least one drum end portion providing an opening at one end of said drum of smaller diameter than that of said drum cylindrical portion, said drum cylindrical and said at least one drum end portion forming a continuous light-tight drum surface,; 2. means for feeding sludge into said opening and against the tapered surface of said first drum end portion at its point of smallest diameter; 3. a first helical conveyor in the interior of said rotary drum disposed to rotate separate from said rotary drum, said helical conveyor extending substantially from said at least one drum end portion through said drum cylindrical portion and being pitched to guide the sewage sludge and separated water in a common direction away from said opening; 4. means for removing the separated water from said rotary drum; and 5. means for removing the sewage sludge from said rotary drum.
Claim 3
Dependent Claim
24 words
means for feeding sludge into said opening and against the tapered surface of said first drum end portion at its point of smallest diameter;
Claim 4
Dependent Claim
24 words
means for feeding sludge into said opening and against the tapered surface of said first drum end portion at its point of smallest diameter;
Claim 5
Dependent Claim
20 words
A decanting centrifuge as claimed in claim 1 wherein said helical conveyor and said rotary drum rotate at different speeds.
Claim 6
Dependent Claim
56 words
a first helical conveyor in the interior of said rotary drum disposed to rotate separate from said rotary drum, said helical conveyor extending substantially from said at least one drum end portion through said drum cylindrical portion and being pitched to guide the sewage sludge and separated water in a common direction away from said opening;
Claim 7
Dependent Claim
56 words
a first helical conveyor in the interior of said rotary drum disposed to rotate separate from said rotary drum, said helical conveyor extending substantially from said at least one drum end portion through said drum cylindrical portion and being pitched to guide the sewage sludge and separated water in a common direction away from said opening;
Claim 8
Dependent Claim
60 words
A decanting centrifuge as claimed in claim 2 wherein said rotary drum comprises two conically tapered drum end portions, said drum cylindrical portion being disposed between first and second drum end portions, said drum portions forming a continuous liquid-tight drum surface, and said means for removing said sewage sludge comprises a discharge unit disposed in said second drum end portion.
Claim 9
Dependent Claim
11 words
means for removing the separated water from said rotary drum; and
Claim 10
Dependent Claim
11 words
means for removing the separated water from said rotary drum; and
Claim 11
Dependent Claim
37 words
A decanting centrifuge as claimed in claim 2 wherein said means for removing the separated water is disposed in the interior of said drum where said drum cylindrical portion are joined and said second drum end portion.
Claim 12
Dependent Claim
10 words
means for removing the sewage sludge from said rotary drum.
Claim 13
Dependent Claim
10 words
means for removing the sewage sludge from said rotary drum.
Claim 14
Dependent Claim
95 words
A decanting centrifuge as claimed in claim 2, further comprising a rotating bowl about which said rotary drum rotates, said bowl comprising conically tapered first and second bowl end portions and a bowl cylindrical portion disposed between said bowl end portions, said bowl end and cylindrical portions providing a continuous liquid-tight surface in said bowl, the diameter of said bowl end portions increasing in the direction of said bowl cylindrical portion, said bowl cylindrical portion and said drum cylindrical portion, and said bowl first end portion and said drum first end portion being substantially aligned.
Claim 15
Dependent Claim
27 words
A decanting centrifuge as claimed in claim 5 wherein said means for removing the separated water comprises a discharge exit disposed in said second bowl end portion.
Claim 16
Dependent Claim
74 words
A decanting centrifuge as claimed in claim 5 wherein said bowl and said drum are disposed so that a space is provided therebetween, and said means for removing sewage sludge comprises a second helical conveyor secured to said rotary drum and disposed in said space between said rotary drum and said bowl, said second helical conveyor being pitched to guide the sewage sludge in a direction opposite to that of said first helical conveyor.
Claim 17
Dependent Claim
48 words
A decanting centrifuge as claimed in claim 7 wherein said means for removing sewage sludge further comprises a discharge exit disposed between the tapered surfaces of said first drum end portion and said first bowl end portion at the points of smallest diameter of said respective end portions.
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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) | 1976-12-31 | 1977-07-02 | 1978-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-31 | 1981-07-02 | 1982-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-31 | 1985-07-02 | 1986-01-01 | $7700.00 | Window Closed / Lapsed |