Spiral membrane element and method of manufacturing the same

Abstract

A spiral membrane element having an enlarged effective membrane surface area without having its separation performance lowered, while maintaining the sealing property of any sealing portion of a cylindrically wound body, and a manufacturing method of the same are disclosed. The spiral membrane element includes a cylindrically wound body comprising a perforated central tube and, spirally wound therearound, a separation membrane, a feed-side passage material and a permeation-side passage material in a laminated state, and a sealing portion for preventing a feed-side fluid and a permeation-side fluid from being mixed together, wherein the sealing portion formed at each of both ends of the cylindrically wound body is spirally formed with a substantially constant width by an adhesive and has a trimmed section formed on its whole end surface, and the cylindrically wound body has a ratio of its length to the length of the central tube of 0.96 to 1.00, and a ratio of an ineffective membrane surface area to the entire membrane surface area of 0.02 to 0.10.

Description

technical field [0001] The present invention relates to a spiral membrane element comprising a cylindrical wound body comprising: a perforated central tube and, surrounding the perforated holes in a laminated state, and a sealing portion The central tube is spirally wound with a separation membrane, a feed-side channel material and a permeate-side channel material; the sealing part is used to prevent the feed-side fluid and the permeate-side fluid from mixing together. Background technique [0002] As a fluid separation element used in reverse osmosis, ultrafiltration, microfiltration, ventilation, exhaust, etc., there is known, for example, a helical fluid separation element comprising: a central pipe and a unit that spirally winds the central pipe, the unit comprising : supply-side channel material and permeation-side channel material, wherein the supply-side channel material guides the supply-side fluid to the surface of the separation membrane, and the separation membran...

AI Technical Summary

Problems solved by technology

[0008] However, the cylindrical jellyroll is sealed (e.g. glued) helically along a certain width towards its ends, unless each such sealed portion has at least a certain axial width, it is not possible to form any reliable seal, and Even though the axial length of the cylindrical jellyroll may be close to the length of the central tube, it is not possible to keep any ineffective membrane surface area below a certain value

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