| 摘要 |
A spiral separation membrane element which can attain a reduced pressure loss in the feed-side passage and is difficult to encounter the problem of flow inhibition or clogging in the feed-side passage. The spiral separation membrane element comprises a perforated cored central tube and, wound therearound, one or more separation membranes, one or more feed-side passage materials, and one or more permeation-side passage materials, wherein the feed-side passage materials each have warps 1 extending almost parallel with the direction of flow of a feed liquid and wefts 2 which are thinner than the warps 1, and a ratio of a pitch of the warps L1 to a pitch of the wefts L2 being from 1/1.5 to 1/6. |
