RIGID SLUDGE DEWATERING FILTER PLATE

摘要

A rigid sludge-dewatering filter plate (1) comprising at least a first layer (2) and a second layer (3), the first layer (2) constituting a flat filtering element consisting essentially of jagged irregular particles (4) and the second layer (3) constituting a particulate support for the first layer (2), characterised in that the particles (4) of the first layer are of a material or materials whose hardness on the Moh scale is at least 7 and which are bonded together with an adhesive bonding agent (18), at least the majority of the particles (4) being of at least two sizes whose average diameter is substantially within the range 0.01 cms to 0.25 cms and being arranged with the average particle size of the particles (4) increasing from an exposed dense upper surface (15) of the first layer (2) to a lower surface (19) thereof, the second layer (3) having particles (5) which are larger than the largest particles in the first layer (2) and the particles (5) of the second layer (3) being bonded together and to the lower surface (19) of the first layer (2) by an adhesive bonding agent (18).