Reverse osmosis membrane module

Claim 1

A spirally wrapped reverse osmosis module membrane for separating a selected fluid component from a feed stock, comprising: a mandrel having an axial passageway forming a flow path for said selected fluid component through said mandrel; a flow guide member for forming a channel for said selected fluid component to said mandrel, said flow guide member spirally wrapped around said mandrel and in fluid communication with said axial passageway; a plurality of generally rectangular membrane envelopes formed from (i) elongated permeate collector sheets, each said collector sheet forming a flow path for said selected fluid component from the outer periphery of each said envelope to said flow guide member, and (ii) folded support sheets placed between and joined to adjacent collector sheets, each said support sheet having membrane areas where reverse osmosis with said feed stock takes place, each said support sheet further being folded in an area where reverse osmosis does not take place, thereby eliminating folded lines on said membrane areas where reverse osmosis of said feed stock does take place; said flow guide member and said envelopes being spirally wrapped around said mandrel such that the distance from the folded edge of each support sheet to the mandrel radially increases along a generally spiral path; and a flow spacer disposed between each adjacent envelope such that one end of said flow spacer is located adjacent the area where said support sheet is folded and where reverse osmosis does not take place, said flow spacer for separating each envelope thereby forming a passageway for the feed stock to flow across the membrane areas on each said envelope.