Patent ID: 8241495

Claim:
A liquid filtration module ( 10 ) comprising: at least one header ( 14 ) and a polymeric membrane sheet ( 12 ) comprising: a first ( 16 ) and second ( 18 ) opposing outer surface bordered by four edges comprising an opposing top ( 20 ) and bottom ( 22 ) edge and an opposing first ( 24 ) and second ( 26 ) lateral edge, a plurality of parallel capillary channels positioned between the first ( 16 ) and second ( 18 ) outer surfaces and extending between two of the four opposing edges of the sheet ( 12 ) such that the capillary channels extend along a path parallel with two of the four edges and perpendicular with two of the four edges, and a bulk section comprising a porous polymeric structure ( 28 ) which provides selective fluid communication between the first ( 16 ) and second ( 18 ) outer surfaces and the capillary channels, and which has a bulk tensile strength, wherein: the header ( 14 ) is disposed along an edge of the membrane sheet ( 12 ) that is perpendicular with the capillary channels and is in fluid communication with the capillary channels, at least one of the two edges of the membrane sheet ( 12 ) extending parallel to the capillary channels has a tensile strength at least twice as great as the bulk tensile strength, and wherein the outer surfaces, ( 16 , 18 ) capillary channels, bulk section, and all four edges ( 20 , 22 , 24 , 26 ) of the polymeric membrane sheet ( 12 ) are formed by co-extrusion and form an integral extruded structure.