Patent ID: 6106715
Filing Date: 2000-08-22
Classification: B01D

Abstract:
A filtration membrane arrangement comprising:at least one membrane unit, said at least one unit comprising opposing layers of flexible filtration membrane sandwiched over a support structure which is arranged to maintain said opposing layers in spaced opposing relationship and provide a central conduit for the passage of fluid to an open end of said at least one unit;said at least one membrane unit being spiral wound about a base axis wherein said open end is arranged adjacent said base axis, with windings of said at least one unit being maintained in spaced opposing relationship to each other by a separator comprising spaced apart elongate primary laths, bridged by cross laths;said primary laths being arranged to extend in about the direction of said base axis, sized to a structural depth which defines the distance of said spaced opposing relationship of said windings of said at least one spiral wound membrane unit by engaging opposing surfaces of said at least one wound membrane unit, and being spaced from each other to form a plurality of distinct elongate passageways between opposing surfaces of said windings, arranged in about the direction of the base axis of the spiral;wherein said cross laths, bridge said elongate passageways, are sized to a structural depth less than the structural depth of said primary laths and are arranged to be spaced from engaging opposing surfaces of said at least one spiral wound membrane unit.