US4541933A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for separation of ash from waste activated sludge
Assignee: Individual
•
Filing: 1984-05-14
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Granted: 1985-09-17
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Expires: 2004-05-14
Abstract
Abstract A process and apparatus for removal of ash from a waste activated sludge stream includes a pressure regulator for controlling the pressure of incoming waste activated sludge containing water or supernatant, carbon and ash as suspended solids; a first stage separation including a plurality of parallel mounted hydrocyclones for receiving the controlled pressure incoming waste activated sludge for separation into a first fluid output containing substantially supernatant and carbon and a second fluid output containing a greater concentration of ash; and a second separation stage including a vibrating screen which receives the second fluid output from the first separation stage, such vibrating screen allowing substantially only the passage of supernatant and carbon therethrough thus producing a third fluid output and a fourth output of ash concentrate which can be ultimately removed from the process.
Inventors
- 👤 Clark W. Armold
- 👤 Michael B. Huebner
- 👤 David Tobin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:25
CPC Classifications
B; B01; B01D; B01D36/00; B01D36/04; B01D36/045; B01D21/00; B01D21/0012; B01D21/24; B01D21/2488; B01D21/26; B01D21/267; B01D21/30; B01D21/34; B01D35/00; B01D35/20; B01D35/28
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
186 words
Process for the substantial removal of ash from a waste activated sludge stream containing supernatant, ash and carbon as suspended solids comprising the steps of: receiving an incoming waste activated sludge stream primarily containing supernatant, ash and carbon; controlling the pressure of said waste activated sludge stream and circulating said waste activated sludge at said controlled pressure to a first separation stage; in said first separation stage, circulating said controlled pressure waste activated sludge through a plurality of hydrocyclones in parallel flow paths to produce a first fluid output substantially containing supernatant and carbon and a second fluid output containing supernatant, carbon and a substantially greater concentration of ash than said first fluid output; collecting said first fluid from said hydrocyclones into a first return output for recirculation back into said sewage treatment process; circulating said second fluid output from said first separation stage through a second separation stage to further separate ash from said first stage second fluid output to produce a second stage third fluid output containing substantially supernatant and powdered carbon and a fourth output which is an ash concentrate for ultimate disposal.
Claim 2
Dependent Claim
186 words
Process for the substantial removal of ash from a waste activated sludge stream containing supernatant, ash and carbon as suspended solids comprising the steps of: receiving an incoming waste activated sludge stream primarily containing supernatant, ash and carbon; controlling the pressure of said waste activated sludge stream and circulating said waste activated sludge at said controlled pressure to a first separation stage; in said first separation stage, circulating said controlled pressure waste activated sludge through a plurality of hydrocyclones in parallel flow paths to produce a first fluid output substantially containing supernatant and carbon and a second fluid output containing supernatant, carbon and a substantially greater concentration of ash than said first fluid output; collecting said first fluid from said hydrocyclones into a first return output for recirculation back into said sewage treatment process; circulating said second fluid output from said first separation stage through a second separation stage to further separate ash from said first stage second fluid output to produce a second stage third fluid output containing substantially supernatant and powdered carbon and a fourth output which is an ash concentrate for ultimate disposal.
Claim 3
Dependent Claim
38 words
The process set forth in claim 1, including the step of: circulating said first separation stage first fluid output and said second stage third fluid output into a common stream for return to a waste water treating process.
Claim 4
Dependent Claim
80 words
The process set forth in claim 1 where the step of circulating said first stage second fluid output through a second separation stage includes the step of: directing said second fluid output, which is underflow from said hydrocyclones, from said first separation stage onto a vibratory screen to allow only a third fluid output substantially containing supernatant and powdered carbon through said screen, and vibrating a fourth output of a heavier concentrate of ash off of said screen for disposal.
Claim 5
Dependent Claim
30 words
The process set forth in claim 3, including: utilizing a vibratory screen having openings of a size to pass substantially only carbon and supernatant which form said third fluid output.
Claim 6
Dependent Claim
27 words
The process set forth in claim 1, wherein: the pressure of the incoming waste activated sludge stream is increased prior to introduction into said first separation stage.
Claim 7
Dependent Claim
20 words
The process set forth in claim 1, wherein: said waste activated sludge stream is blown down from an autothermal reactor.
Claim 8
Dependent Claim
30 words
The process set forth in claim 1, wherein: said waste activated sludge stream is the continuous flow stream having a wet air oxidation reactor containing supernatant, reactivated carbon and ash.
Claim 9
Dependent Claim
22 words
The process set forth in claim 1, wherein: said waste activated sludge stream is return activated sludge from a secondary clarifier system.
Claim 10
Dependent Claim
15 words
The process set forth in claim 1, wherein: said first fluid output is a supernatant.
Claim 11
Dependent Claim
22 words
The process set forth in claim 1, wherein: said fourth output from said second stage separation is partially in a cake-like form.
References Cited (Backward Citations)
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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) | 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 |