| 摘要 |
PCT No. PCT/US93/00562 Sec. 371 Date Jul. 21, 1994 Sec. 102(e) Date Jul. 21, 1994 PCT Filed Jan. 19, 1993 PCT Pub. No. WO92/14205 PCT Pub. Date Aug. 20, 1992A method for filtering an aqueous mineral slurry and collection of the mineral as product. The slurry is flowed through a filter plate of the type characterized by a porous support layer and an overlying microporous metal filtration layer, with flow through the filter plate during filtration being from the filtration layer side toward the base layer and being effected by establishing a fluid pressure differential across the filter plate. The filtration layer preferably comprises a sintered metal, with a relatively narrow pore size distribution, i.e. one wherein substantially all of the pores are less than 5 mu m. Discharge of the filter cake which accumulates upon the plate during filtration, is facilitated by subjecting the support layer side of the plate to one or more positive water pressure pulses, to effect a transient reverse water flow through the plate, thereby generating via the uniform pore structure of the filtration layer a uniform back pressure and a lubricating film of water at the interface between the filtration layer and the filter cake. Controlled oscillations or vibrations are simultaneously or shortly thereupon imparted to the surface of the porous filtration layer to facilitate separation of the filter cake.
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