US 8,709,253 B2 · Separation membrane elements, separation membrane module, and process for producing separation membrane element

Abstract

The invention offers a separation membrane element that can be produced by a method in which a membrane-sealing portion is formed by, first, immersing end portions of hollow-fiber-shaped porous separation membranes in a resinous liquid and, then, curing the resin, that has a feature in that the membrane-sealing portion is formed of a casting resin and pores of the hollow-fiber-shaped porous separation membranes are filled with a pore-filling resin at the portion at which the membranes are in contact with the membrane-sealing portion, so that the casting resin is strongly bonded with the pore-filling resin, and that has the hollow-fiber-shaped porous separation membranes whose basal portions are flexible, so that breakage of the basal portions and leakage of gas or liquid are less likely to occur when in use; a separation membrane element that has a feature in that in the membrane-sealing portion, at least the surface at a side that is to be in contact with a liquid to be treated is formed of a thermosetting fluororesin, so that the membrane-sealing portion has excellent chemical resistance comparable to that of the conventional membrane-sealing portion formed of a thermoplastic fluororesin; separation membrane modules having these separation membrane elements as constituting elements; and a method of producing the separation membrane element.

Claims14

Dependent claims

A separation membrane element, comprising a plurality of hollow-fiber-shaped porous separation membranes and a membrane-sealing portion that bundles end portions of the hollow-fiber-shaped porous separation membranes together to seal the end portions;

wherein in the membrane-sealing portion, at least the surface at a side that is to be in contact with a liquid to be treated is formed of a thermosetting fluororesin, wherein the hollow-fiber-shaped porous separation membranes are formed of a fluororesin.

A method of producing a separation membrane element comprising a plurality of hollow-fiber-shaped porous separation membranes and a membrane-sealing portion that bundles end portions of the hollow-fiber-shaped porous separation membranes together to seal the end portions, the method comprising the steps of:

(a) bundling end portions of the multiple hollow-fiber-shaped porous separation membranes together to set the end portions in a mold;
(b) casting a thermosetting resin, which is uncured, into the mold;
(c) after the casting, curing the thermosetting resin to seal the end portions of the hollow-fiber-shaped porous separation membranes;
(d) in the thermosetting resin, which has been cured, applying a thermosetting fluororesin, which is uncured, onto at least the surface at a side from which the hollow-fiber-shaped porous separation membranes extend;
(e) after the applying, curing the thermosetting fluororesin;
and
(f) removing the thermosetting resin, which has been cured, from the mold and performing a cutting-away operation at the end-portion side of the hollow-fiber-shaped porous separation membranes to form openings of the hollow-fiber-shaped porous separation membranes, wherein the hollow-fiber-shaped porous separation membranes are formed of a fluororesin.

4 more elements

(a) bundling end portions of the multiple hollow-fiber-shaped porous separation membranes together to set the end portions in a mold;
(b) casting a thermosetting fluororesin, which is uncured, into the mold;
(c) after the casting, curing the thermosetting fluororesin to seal the end portions of the hollow-fiber-shaped porous separation membranes;
and
(d) removing the thermosetting fluororesin, which has been cured, from the mold and performing a cutting-away operation at the end-portion side of the hollow-fiber-shaped porous separation membranes to form openings of the hollow-fiber-shaped porous separation membranes, wherein the hollow-fiber-shaped porous separation membranes are formed of a fluororesin.

2 more elements

Dependencies are inferred from the claim text.

Separation membrane elements, separation membrane module, and process for producing separation membrane element

Life of this patent

Separation membrane elements, separation membrane module, and process for producing separation membrane element

Life of this patent

Abstract

Claims14