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Water clarification by filtration methods

General information

Clarifying (mechanical) filters are used to clean surface sources' water from particulate pollutants or clean clarified water from finely-dispersed sludge downstream the clarifier. During the filtration of water through the porous media the suspended particles are retained inside or on the surface of the ion-exchange resin, as a result the permeate is clarified. The effectiveness of the filtration process depends on physical and chemical properties of water impurities and porous media, as well as hydrodynamic factors. The porous media of clarifying filters usually is formed by granular solids with the certain diameter. In the formed layer the material particles interchange with cavities called pores that create non-linear porous channels enabling treated water to flow through.

The backwash of clarifying filters is performed by water supplied with a rate appropriate to transfer filtering materials in suspended (pseudo-liquefied) state. During this process previously retained particles are separated off and removed from upper section of the clarifying filter by loosening water flow.

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* The text is taken from:
A.S. Kopylov, V.M. Lavygin, V.F. Ochkov, "Water-treatment in power energetics"
(M. MEI Publishing House, 2003)