Patent ID: 6277282
Filing Date: 2001-08-21
Classification: B01D

Abstract:
A reverse osmosis membrane element, comprising a reverse osmosis membrane, a permeated liquid passage conduit provided in a facing relationship on one surface of said reverse osmosis membrane, and a water permeable fabric interposed between said reverse osmosis membrane and said permeated liquid passage conduit,said permeated liquid passage conduit having a surface structure comprising a plurality of alternating unidirectionally oriented projections and grooves having a structural strength to resist deformation in use at a high liquid pressure,said grooves having a width of 100 to 200 .mu.m thereby inhibiting depression of said reverse osmosis membrane into said grooves at a high pressure, and having a depth of 50 to 200 .mu.m to achieve decreased fluid flow resistance in said grooves, andsaid grooves having a density of 45 to 70 grooves per inch of length of said reverse osmosis membrane,wherein the water permeable fabric is a nonwoven fabric,wherein said nonwoven fabric is composed of a multiplicity of single fibers or filaments that are oriented substantially in the same direction, and in a direction substantially perpendicular to the orientation of said grooves of said permeated liquid passage conduit, andwherein the strength of said nonwoven fabric is substantially about 3 to 5 times stronger in a direction parallel to the direction of the oriented fibers or filaments than in a direction perpendicular thereto.