Hollow fiber separatory module with encased fiber bundle

Claim 1

A hollow fiber separatory module for separating fluid elements into permeate and raffinate, said separatory module defining first and second ends, comprising: an annular helically wound hollow fiber bundle defining first and second ends, said bundle being enrobed on its outer surface by a thin closely conforming barrier layer of material substantially impermeable to feed fluid, said layer extending over the entirety of said outer surface except for said first end and a non-enrobed circumferential region adjacent said first end of said bundle; an end-cap sealed at said second end of the bundle to the impermeable barrier; a pressure resistant shell encasing the hollow fiber bundle and defining a channel between the pressure resistant shell and the hollow fiber bundle, said channel originating adjacent to an inlet feed means and terminating at said non-enrobed circumferential region and defining a portion of a flow path for raffinate material; said inlet feed means passing through the end cap for communicating between a source of feed fluid and said bundle; a first exit means at said first end of the separatory module in fluid communication with the fiber bundle and an area exterior to the separatory module for permitting exit of raffinate material; and a second exit means at said second end of the separatory module in fluid communication with the fiber bundle and an area exterior to the separatory module for permitting exit of permeate material.