SPIRAL MEMBRANE ELEMENT

• Main Authors: NISHI MIEKO, ECHIZEN SUSUMU, OKAZAKI YUHA
• Format: Patent
• Language: English; Japanese
• Published: 06.07.2017
• Subjects: PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TRANSPORTING

PROBLEM TO BE SOLVED: To provide a spiral membrane element which can enhance an effective membrane area of a composite semipermeable membrane, and can suppress a reduction in a rejection rate caused by deformation of the composite semipermeable membrane while sufficiently securing a flow rate of a permeated liquid passing through a permeation side flow channel.SOLUTION: In a spiral membrane element having a laminate containing a composite semipermeable membrane, a supply side flow channel material and a permeation side flow channel material 3, the permeation side flow channel material 3 is formed of a tricot knit having a plurality of ridges 3b formed of loops 3a linearly repeating in a vertical direction, and a plurality of grooves 3c existing between the ridges 3b, a membrane support index calculated from a groove number (wale) per 25 mm×{ridge width Wb(mm)/groove width Wc(mm)} is 60-135, and a flow channel index calculated from a number (course) of loops 10a forming a ridge 10b per {groove width Wc(mm)×groove depth D(mm)×groove number (wale) per 25 mm}/25 mm is 0.18-0.45(mm).SELECTED DRAWING: Figure 2 【課題】複合半透膜の有効膜面積を高めることができ、透過側流路を流れる透過液の流量を十分確保しながら、複合半透膜の変形による阻止率の低下を抑制できるスパイラル型膜エレメントを提供する。【解決手段】複合半透膜、供給側流路材及び透過側流路材３を含む積層体を備えるスパイラル型膜エレメントにおいて、透過側流路材３は、縦方向に直線状に繰り返すループ３ａにより形成される複数の畝３ｂと、それらの畝３ｂ同士の間に存在する複数の溝３ｃとを有するトリコット編物により形成され、２５ｍｍ当たりの溝数（ｗａｌｅ）×｛畝幅Ｗｂ（ｍｍ）／溝幅Ｗｃ（ｍｍ）｝から計算される膜支持指数が６０〜１３５であり、｛溝幅Ｗｃ（ｍｍ）×溝深さＤ（ｍｍ）×２５ｍｍ当たりの溝数（ｗａｌｅ）｝／２５ｍｍ当たりの畝１０ｂを形成するループ１０ａの数（ｃｏｕｒｓｅ）から計算される流路指数が、０．１８〜０．４５（ｍｍ２）であることを特徴とする。【選択図】図２