Abstract: A method and apparatus for backwashing filter elements in a filter vessel. At least one collapsible bladder in the form of a tube is suspended together with a plurality of filter elements in a mixture compartment of a vessel for filtering solids from a liquid-solids mixture, the tube having a volumetric displacement at least as great as the volume of filtrate required to flow from a filtrate compartment into the filter elements to slightly expand filter fabric enveloping the filter elements to disengage filtercake deposited thereon. Means are provided to fill the tube with fluid for expansion thereof and to rapidly empty fluid from the tube for sudden collapse of the tube and attendant rapid reverse flow of filtrate from the filtrate compartment.

Abstract: A filter-thickening apparatus including a thickener tank having tubular filter units suspended therein is disclosed. A liquid-solids suspension is supplied to the tank and an overflow pipe is spaced in a filtrate compartment above the filter units for draining a filtrate liquid from the tank. The filter units preferably include either an accumulator grating or a filter cloth which is sealed along narrow bands to form a pattern of filtering areas or both. Processes for filtering the liquid-solids suspension are also disclosed.

Abstract: This invention relates to a continuous flow gravitational separator having inclined membrane baffles therein which separates solid particles and also foam from a suspension liquid. A rectangular membrane assembly with a plurality of parallel inclined flexible membranes is received in a cylindrical tank, thereby defining four vertically extending arc-shaped compartments or segments between the membrane assembly and the wall of the tank. The tank has a funnel shaped bottom solids outlet and oppositely located inflow and outflow segments are connected respectively to the liquid inlet and outlet. The liquid flow across the inclined compartments between the membranes is distributed evenly by vertical inflow and outflow distributor plates. The solid particles settle along the inclined membranes to a solids receiving segment, while the foam rises along the membranes to an oppositely located foam receiving segment.