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US5494581A Expired / Lapsed US ⏱️ 0.0 years remaining

Treatment of water, sewage and like waste liquids

Assignee: WRC PLC
•
Filing: 1994-01-14
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Granted: 1996-02-27
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Expires: 2014-01-14
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Abstract

Abstract A process for the treatment of water or other liquid has a plurality of stationary surfaces on which microorganisms or like biologically active materials are fixed or grown which are contacted alternately with air and the liquid undergoing treatment by raising and lowering the liquid. This leads to purification by biological oxidation and other processes. Apparatus for performing the process comprises a tank containing arrays of plates and a wave generator for generating a wave action of liquid in the tank by means of which the alternate raising and lowering of the liquid is achieved. Beneficially the wavelength of the wave motion is arranged such that the tank length is 1/2, 1 or n times the wavelength where 2×n is an integer.

Inventors

  • 👤 John A. Hobson

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 20:35
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/02; C02F3/12; C02F3/1278; C02F3/1284; C02F3/06; C02F3/10; C02F3/101; E; E04; E04H; E04H4/00; E04H4/0006; Y; Y02; Y02W; Y02W10/00; Y02W10/10

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 44 words
A process for the treatment of liquid in a tank in which stationary surfaces having biologically active material fixed to or growing thereon are contacted alternately with air and the liquid undergoing treatment by raising and lowering said liquid by artificially induced wave action.
Claim 2
Dependent Claim 44 words
A process for the treatment of liquid in a tank in which stationary surfaces having biologically active material fixed to or growing thereon are contacted alternately with air and the liquid undergoing treatment by raising and lowering said liquid by artificially induced wave action.
Claim 3
Dependent Claim 27 words
A process as claimed in claim 1, in which the stationary surfaces take the form of an array of plates which are substantially parallel to one another.
Claim 4
Dependent Claim 24 words
A process as claimed in claim 2, in which the plates are arranged in a tank adapted to contain the liquid to be treated.
Claim 5
Dependent Claim 45 words
A process as claimed in claim 1, in which the wave action comprises a stationary, standing or non-progressive wave, arising from a resonant frequency of the tank, the length of said tank being an integral or half-integral number of wavelengths characteristic of the wave motion.
Claim 6
Dependent Claim 50 words
A process for the treatment of water in a tank in which stationary surfaces having micro-organisms growing thereon are contacted alternately with air and water undergoing treatment by raising and lowering the water by artificially induced wave action which causes the water to move substantially horizontally past said stationary surfaces.
Claim 7
Dependent Claim 50 words
A process for the treatment of water in a tank in which stationary surfaces having micro-organisms growing thereon are contacted alternately with air and water undergoing treatment by raising and lowering the water by artificially induced wave action which causes the water to move substantially horizontally past said stationary surfaces.

References Cited (Backward Citations)

FR795834A Cited
DE2221382A1 Cited
US4100063A Cited
DE3150912A1 Cited
DE3434144A1 Cited
US4966096A Cited
SU1750530A1 Cited
US5262051A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-02-26 1999-08-28 2000-02-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-02-26 2003-08-28 2004-02-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-02-26 2007-08-28 2008-02-27 $7700.00 Window Closed / Lapsed

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