To provide a spiral type separation membrane element capable of suppressing pressure loss in a channel in the supply side and giving high operation efficiency and good filtered water quality owing to a sufficient effect for suppressing concentration polarization.
The spiral type separation membrane element comprises a separation membrane, a channel material in the supply side, and a channel material in the filtered side which are rolled around a hollow center pipe having holes. The channel material in the supply side is composed of warp yarns 1 parallel to the flow direction of the supplied liquid and weft yarns 2 crossing the flow direction of the supplied liquid, wherein both yarns are entwisted at a crossing angle θ of 20 to 80° and have the ratio (L1/L2) of the intervals L1 of the warp yarns and the intervals L2 of the weft yarns in a range from 1.3 to 2.0, and the intervals L1 of the warp yarns is 5 mm or wider.
COPYRIGHT: (C)2007,JPO&INPIT
UDA YASUHIRO
Yuzo Ozaki
Toshihiko Taniguchi