Abstract: A filtration housing for a filter cassette includes a base frame means supporting a first and second parallel plate to be movable thereon relative to each other in directions normal thereto. The filtration cassette being retained between opposing first major surfaces of the parallel plates with the direction of movement thereof aligned with the axis of the membrane sheets. The first plate defines a first channel substantially parallel to and axially aligned with first edges of the cassette, a second channel substantially parallel to and axially aligned with the second edges of the cassette, and a third channel means including a first portion acutely oriented with respect to either of the first and second edges of the cassette and a second portion optionally substantially transversely oriented with respect to the first and second edges of the cassette or acutely oriented thereto and extending a distance therebetween.

Abstract: Porous hollow polymer fiber membranes having convoluted inside and/or outside surfaces, as well as filter devices comprising a plurality of the hollow fiber membranes, the devices preferably being arranged to direct fluid flow from the inside surface of the membranes to the outside surface, methods of making the membranes, and methods of using the filter devices, are disclosed.