SPIRAL MEMBRANE ELEMENT

• Main Authors: Nishi, Mieko, Uda, Yasuhiro
• Format: Patent
• Language: English
• Published: 22.08.2019
• Subjects: PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TRANSPORTING

Provided is a spiral membrane element that has a restricted outer diameter and is capable of being decreased in operation energy therefor. The element is a spiral membrane element including plural membrane leaves in each of which a permeation-side flow-channel member is interposed between opposed separation membranes; a supply-side flow-channel member interposed between any two of the membrane leaves; a perforated central pipe on which the membrane leaves and the supply-side flow-channel member are wound; and a sealing part that prevents a supply-side flow-channel member from being mixed with a permeation-side flow-channel member. This element has an efficiency index E of 0.005 to 0.10, the index being calculated in accordance with an expression described below, and the thickness of the supply-side flow-channel member is from 10 to 110 mil. Efficiency index: E=0.0024×X−0.2373+(Y/(D2×L)) wherein X is a thickness [mil] of the supply-side flow-channel member, Y is an effective membrane area [ft2] of the separation membranes, D is an outer diameter [inch] of the membrane element, and L is a length [inch] of the membrane element.