Spiral type separation membrane element

Abstract

An object of the invention is to provide a spiral separation membrane element that can reduce the pressure loss of a feed-side channel and be much less vulnerable to the problem of inhibition or blockage of the flow in the feed-side channel. The spiral separation membrane element includes one or more separation membranes, one or more feed-side channel components, one or more permeation-side channel components, and a perforated hollow core tube around which the separation membranes, the feed-side channel components and the permeation-side channel components are wrapped, wherein the feed-side channel component is a net formed by fusion bonding.

1 . A spiral separation membrane element, comprising one or more separation membranes, one or more feed-side channel components, one or more permeation-side channel components, and a perforated hollow core tube around which the separation membranes, the feed-side channel components and the permeation-side channel components are wrapped, wherein the feed-side channel component is a net formed by fusion bonding.  
   
   
       2 . The spiral separation membrane element according to  claim 1 , wherein the feed-side channel component comprises weft yarns crossing the direction of feed fluid flow and warp yarns arranged along the direction of feed fluid flow, and the weft yarns are thinner than the warp yarns.  
   
   
       3 . The spiral separation membrane element according to  claim 1 , wherein the feed-side channel component is a net channel component that is structured to have meandering warp yarns arranged along the direction of feed fluid flow.  
   
   
       4 . The spiral separation membrane element according to  claim 1 , wherein 
 the feed-side channel component has a two-layer structure comprising a first layer composed of first yarns and a second layer composed of second yarns,    the first and second yarns each have a parallel part repeated and arranged substantially parallel to the direction of feed fluid flow and an oblique part repeated and arranged in a direction oblique to the direction of feed fluid flow, and    the parallel part of the first yarn and the parallel part of the second yarn are fused and bonded to form a hexagonal plane unit.    
   
   
       5 . A spiral separation membrane element, comprising one or more separation membranes, one or more feed-side channel components, one or more permeation-side channel components, and a perforated hollow core tube around which the separation membranes, the feed-side channel components and the permeation-side channel components are wrapped, wherein 
 the feed-side channel component is a net formed by fusion bonding and has a three-layer structure comprising warp yarns arranged substantially parallel to the direction of feed fluid flow, oblique yarns arranged in a direction oblique to the direction of feed fluid flow, and reverse oblique yarns arranged in a direction that is reversely oblique to the direction of feed fluid flow with respect to the direction of the oblique yarns.    
   
   
       6 . The spiral separation membrane element according to  claim 2 , wherein the feed-side channel component is a net channel component that is structured to have meandering warp yarns arranged along the direction of feed fluid flow.  
   
   
       7 . The spiral separation membrane element according to  claim 1 , wherein the feed-side channel component net formed by fusion bonding has a relatively smooth surface as compared to the surface of the products formed by the shear method whereby damage to the membrane by contact with or wrapping and pressing onto the membrane surface is lessened in the process of assembling the element.  
   
   
       8 . The spiral separation membrane element according to  claim 1 , wherein at least one channel component is a ladder-type channel component.  
   
   
       9 . The spiral separation membrane element according to  claim 1 , wherein at least one channel component is a hexagonal-type channel component.  
   
   
       10 . The spiral separation membrane element according to  claim 1 , wherein at least one channel component is a three layer-type channel component.  
   
   
       11 . The spiral separation membrane element according to  claim 2 , wherein the ratio of the diameter of the warp yarn to that of the weft yarn (warp:weft) is properly from 4:1 to 2:1.  
   
   
       12 . A method of treating suspended matter-containing waste water comprising the steps of contacting said waste water with a spiral separation membrane element containing the feed-side channel component of  claim 1 , whereby components in said waste water are separated.  
   
   
       13 . A method for manufacturing a feed-side channel component for use in a spiral separation membrane element by fusion bonding, comprising the steps of: 
 extruding weft and warp yarns from a number of nozzle holes arranged at two circumferential portions of dies including inner and outer portions in an extruder while rotating the inner and outer nozzle holes in opposite directions, wherein the nozzle holes are arranged so that both nozzle holes do not overlap one another at the intersections of the weft and warp yarns; and    fusing and bonding the extruded weft and warp yarns to each other to form intersections with timing of fusion bonding.