US5024762A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Concentration of solids in a suspension
Assignee: US Filter Wastewater Group Inc
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Filing: 1990-01-05
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Granted: 1991-06-18
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Expires: 2010-01-05
Abstract
Abstract A method of concentrating solids in a liquid suspension using a filter having a plurality of hollow, microporous, elastic fibres with a shell or housing, comprising applying the suspension to an outer surface of the fibres whereby a portion of the suspension passes through the fibre walls and at least a portion of the solids is retained on or in the fibres; and discharging the retained solids by stretching the fibre pores and washing out solids retained in the pores by application of gas under pressure.
Inventors
- 👤 Douglas L. Ford
- 👤 Eric W. Anderson
- 👤 Clinton V. Kopp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:54
CPC Classifications
B; B01; B01D; B01D63/00; B01D63/02; B01D61/00; B01D61/14; B01D61/18; B01D65/00; B01D65/02; B01D69/00; B01D69/02; B01D2313/00; B01D2313/48; B01D2321/00; B01D2321/18
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
145 words
A concentrator for concentrating the fine solids of a liquid feed suspension comprising: (i) a shell, (ii) a plurality of elastic, hollow, microporous, polymer fibres within the shell, (iii) means for supplying pressurised feed suspension to the outside of the fibres, (iv) means for withdrawing clarified liquid from the fibre lumens, (v) means for applying liquid followed by gas under pressure to the fibre lumens to effect a transmembrane cleaning of the fibres, the pressure of the liquid being sufficient to stretch substantially all of the pores of the fibres and the pressure of the gas being sufficient to ensure that the gas will pass through the larger pores of the fibres to dislodge any solids retained therein and to wash the external walls of the fibres and the interior of the shell to remove all solids from the shell to an external collection point.
Claim 2
Dependent Claim
145 words
A concentrator for concentrating the fine solids of a liquid feed suspension comprising: (i) a shell, (ii) a plurality of elastic, hollow, microporous, polymer fibres within the shell, (iii) means for supplying pressurised feed suspension to the outside of the fibres, (iv) means for withdrawing clarified liquid from the fibre lumens, (v) means for applying liquid followed by gas under pressure to the fibre lumens to effect a transmembrane cleaning of the fibres, the pressure of the liquid being sufficient to stretch substantially all of the pores of the fibres and the pressure of the gas being sufficient to ensure that the gas will pass through the larger pores of the fibres to dislodge any solids retained therein and to wash the external walls of the fibres and the interior of the shell to remove all solids from the shell to an external collection point.
Claim 3
Dependent Claim
69 words
The concentrator according to claim 1, and further includes, means for sealing the relatively incompressible feed suspension in the shell upon displacement of liquid from the fibre lumens by the pressurised gas so that the gas may be trapped in the lumens at a pressure above the bubble point of the fibre walls and means to allow the sudden release of the gas substantially uniformly through the fibre walls.
Claim 4
Dependent Claim
88 words
The concentrator as claimed in claim 1 or claim 2, which incorporates means whereby the resumption of flow of feed suspension through the fibres after said liquid and said gas are applied to the fibre lumens so as to wash the external walls of the fibres and the interior of the shell is delayed for sufficient time to allow the expanded pores to recover to their original size so that oversized particles from the feed suspension will not be able to pass into or through the enlarged pores.
Claim 5
Dependent Claim
73 words
The concentrator according to claim 3, wherein said means for delaying the resumption of the flow of feed suspension effects said delay by applying the gas at a pressure higher than that of the feed suspension and allowing the pressure of the gas to fall below the feed pressure at a rate which will allow the pores of the fibres to recover to their original size before the flow of feed is resumed.
Claim 6
Dependent Claim
25 words
The concentrator as claimed in claim 2, wherein said means for sealing the relatively incompressible feed suspension within said shell comprises the feed liquid itself.
Claim 7
Dependent Claim
30 words
The concentrator as claimed in claim 1, wherein flow of treated suspension from said shell is controlled by valve means so as to apply a back pressure to the feed.
Claim 8
Dependent Claim
31 words
The concentrator as claimed in claim 1, wherein means is provided to wet the pores of said fibres following removal of all solids from said shell to an external collection point.
Claim 9
Dependent Claim
56 words
The concentrator as claimed in claim 1, wherein means is provided to shrink the gas bubbles retained in the pores of the fibres following discharge of the solids so as to aid the passage of the bubbles from the pores and to maintain sufficient solubility of the gas in the feed or clarified liquid or both.
Claim 10
Dependent Claim
37 words
The concentrator as claimed in claim 8, wherein said means to shrink the gas bubbles effects the shrinking of the gas bubbles following resumption of feed by application of sufficient pressure of feed to cause said shrinkage.
References Cited (Backward Citations)
US4816160A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-06-17 | 1994-12-17 | 1995-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-06-17 | 1998-12-17 | 1999-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-06-17 | 2002-12-17 | 2003-06-18 | $7700.00 | Window Closed / Lapsed |