Abstract: A filter assembly includes a housing divided into a first chamber and a second chamber. A filter element is disposed in the first chamber, and a conduit is disposed in and opens to the second chamber. A weep hole introduces a backwash liquid from the second chamber into the filter element or the conduit. A differential pressure is then established between the opening in the conduit and the exterior of the filter element to force the backwash liquid through the filter element and thereby clean the filter element and/or strip a precoat layer from the filter element.

Abstract: A precoat filter element for a precoat filter unit comprises a flow distributor and flow straightener. The flow distributor surrounds a filter septum and has openings through which liquid may flow. The proportion between the area of openings and the area of a wall of the flow distributor may vary along the length of the septum to distribute flow over the length of the filter septum in a predetermined manner. A flow straightener is provided at the base of the septum to reduce turbulence during precoat and filtration operations, and to reduce the occurrence of large flocs in precoat slurries during coating operations.