JPH04135630A - Hollow yarn membrane filteration module - Google Patents

Abstract

PURPOSE:To improve heat cycle resistance by disposing a flexible adhesive layer in an annular shape in such a manner that this layer is pinched by nonflexible adhesive layers from both sides in the position where the flexible adhesive layer comes into contact with the inside surface of a cylindrical case on the outer side of hollow yarn membrane bundles. CONSTITUTION:Plural pieces of the hollow yarn membranes 4 are housed into the cylindrical case 1 and the hollow yarn membranes 4 are fixed to the cylindrical case 1 by the adhesive layer at both or one end of the cylindrical case 1. The flexible adhesive layer 2 is disposed in an annular shape by pinching this layer with the nonflexible adhesive layers 3 from both sides in the position in contact with the inside surface of the cylindrical case 1 on the outer side of the hollow yarn membrane 4 bundles. Consequently, the heat cycle resistance is improved and the eluted components from the adhesive layers is extremely decreased. The membrane is thus usable safely even in the field of ultrapure water, drugs, food, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hollow fiber membrane filtration module suitable for filtration using fibers subject to rapid temperature changes, particularly for high temperature sterilization and hot water filtration.

[Conventional technology]

Flat membrane modules are commercially available in which the case and membrane are made of the same material, and both ends are firmly sealed by heat fusion. On the other hand, if a hollow fiber membrane module is sealed by heat fusion, the hollow fiber membrane will melt, the inner diameter of the hollow fiber membrane will become extremely small, or the membrane will close. A method of firmly sealing using a thermosetting resin or a liquid thermosetting resin is used.

However, since the liquid casting resin and the case material are usually made of different materials, when used in systems with large temperature changes such as steam sterilization at 121°C or hot water filtration, distortion due to the difference in thermal expansion coefficient between the painting materials may occur. will receive. This strain is especially large for large membrane modules with large case dimensions.
Conventional hollow fiber membrane filtration modules could practically only be used within a temperature range of ±20°C from room temperature because they are susceptible to adhesive peeling and cracking of the sealing resin due to heat cycles.

In order to solve these problems, the percentage opening is 61-15.
As seen in Japanese Patent Laid-Open No. 7307 and Japanese Patent Laid-Open No. 61-15730P, a membrane module with good heat cycle properties has been proposed by combining a ground adhesive and a non-flexible adhesive.

[Problem to be solved by the invention]

However, in these membrane modules, the visible adhesive is exposed on the outer surface, and when it comes into contact with hot water, there are extremely large amounts of components eluted from the visible adhesive. It could not be practically used in this field, and its applications were limited.

The present invention provides a filtration module that has good heat cycle resistance, has extremely low amounts of components eluted from the adhesive layer, and can be used in fields such as ultrapure water, medicine, and food.

[Means to solve the problem]

The gist of the present invention is that a plurality of hollow fiber membranes are housed in a cylindrical case, and at both ends or one end of the cylindrical case, the hollow fiber membranes are placed in contact with the inner surface of the cone through an adhesive layer.
The hollow fiber membrane filtration module has a flexible adhesive layer arranged in a ring shape so as to be sandwiched between non-flexible adhesive layers from both sides.

In the filtration module of the present invention, the hollow fiber membrane bundle is arranged in a known shape, such as a straight line or a U-shape, within a cylindrical case, and both ends or one end thereof are fixed with an adhesive.

In the present invention, a scorable adhesive is defined as having a tensile elongation at room temperature of 154 as measured by JIS K7113.
Of the above, those having a tensile elongation at break of about 50 to 5004 are particularly preferred.

As the visible adhesive, natural rubber, synthetic rubber, polysulfide rubber, epoxy adhesive having a dimer acid skeleton, adhesive having a cyrocan bond, adhesive having a urethane bond, etc. are used. In addition, the non-flexible adhesive refers to an adhesive having a tensile modulus of elasticity at room temperature of 1x I D'dyne/cm'' or more as measured by Jxsx7113, and particularly preferably one having an I x 1010 dyne/σ2 or more.

As the non-flexible adhesive, a conventional epoxy adhesive having good heat resistance and chemical resistance may be used. As for the thickness of the visible adhesive layer in the radial direction, the thicker it is, the greater its ability to absorb changes in volume due to expansion and contraction, but if it is too thick, it will lack pressure resistance in the longitudinal direction of the cylindrical case. It turns out. Therefore, although it depends on the size of the hollow fiber membrane module, especially the inner diameter of the cylindrical case and the filling wheel of the hollow fiber membrane, the thickness is usually (preferably about L1 to 5 mm).

When a thermal shock is applied to a hollow fiber filtration module, the case and adhesive layer repeatedly expand and contract. Therefore, if the adhesive layer is only a non-flexible adhesive, even if it has heat resistance, the adhesive layer itself has almost no elasticity, so it cannot absorb shock, and it cannot be bonded to the cylindrical case. When peeling occurs between the agent layers, it becomes difficult. Further, if the entire adhesive is made of visible adhesive, it is possible to absorb thermal shock, but conversely, the adhesive layer deforms when used under high temperature and high differential pressure. The hollow fiber filtration module of the present invention takes advantage of the advantages of both liquid adhesives, overcoming their drawbacks.

Examples of the present invention will be shown below and will be explained more specifically.

Example 1 5 to 15 mm from the lower end along the inner surface of a polysulfone case with an inner diameter of 80 mm, an outer diameter of 90 mm, and a length of 3005 m.
Flexible epoxy resin (PM2 manufactured by Cemedine M) is applied to the position of
A cured product consisting of 1 D, elongation at break at room temperature of 1374) was applied to a thickness of 2 cm. After the resin has hardened, the polyethylene porous hollow fiber membrane bundle is inserted into the case, and a non-flexible epoxy resin (FF1P made by Yuka Shell Epoxy ■) is inserted into the case.
834; 153 parts by weight, LP-2 manufactured by Toshi Thiokol ■;
50 parts by weight, Nippon Kayaku C-950; 1? Cured product consisting of parts by weight, tensile modulus at room temperature I x 10” ayn
θ/ex"). At this time, the total resin layer height was 20 cm. Similarly, adhesive was applied and injected on the other end side, and both ends were cut.

80℃ for the filtration module manufactured in this way.
25°C water for 10 minutes, and immediately after passing through the hot water for 10 minutes.
A heat cycle test was conducted in which one cycle was permeation for one minute.

Even after repeating 500 times, there was no cracking of the casting resin (adhesive layer) or leakage from the seal, and the results were good.

In addition, immediately after sterilizing the filtration module at 121°C for 30 minutes, water at 25°C was added at 10°C.
A heat cycle test was conducted in which one cycle was paving for one minute.

Even after repeating the process 100 times, there was no cracking of the casting resin or leakage from the seal, and the results were good.

In addition, this module was heated to 24°C with 80"C pure water inside.
After soaking for hr, Too was measured and found to be α1 ppm, which is extremely small.

Comparative Example 1 A module was manufactured in exactly the same manner as in Example 1 without using any flexible epoxy resin.

There was no leakage at the beginning, but leakage started to occur after 80°C hot water and 25°C water were alternately passed through it 5 times.

Comparative Example 2 Inner surface of polysulfone case in Example 1! !
A wall joule was produced in the same manner as in Example 1, except that the width of the flexible epoxy resin to be clothed was 20 mm, and the flexible epoxy resin was arranged throughout the thickness of the adhesive layer. A similar evaluation was conducted.

In the heat cycle test, no leakage occurred and the results were good, but in the elution test, TOO was as high as 10 ppm, and there was a very high elution.

〔Effect of the invention〕

The filtration module of the present invention uses a combination of a non-flexible resin with excellent heat resistance and pressure resistance and a flexible resin with excellent thermal shock resistance in the adhesive layer, so it is a thread that is subject to rapid temperature changes. Can be used for a long time.

In addition, in the adhesive layer, since the flexible resin is not exposed on the outer surface side, it is possible to provide a filtration module with extremely low eluted components in hot water, and it is possible to provide a filtration module that has extremely low eluted components in hot water.
It can be used with confidence in fields such as pharmaceuticals.

[Brief explanation of drawings]

FIG. 1 is a partial schematic longitudinal cross-sectional view of the hollow fiber membrane filtration module of the present invention, showing a portion of the adhesive layer. 1...Cylindrical case 2...Flexible resin 3...Non-flexible resin 4...Hollow fiber membrane Fig. 1

Claims (1)

[Claims] In a hollow fiber membrane filtration module in which a plurality of hollow fiber membranes are housed in a cylindrical case and the hollow fiber membranes are fixed to the cylindrical case by an adhesive layer at both ends or one end of the cylindrical case, the hollow fiber membranes are Hollow fiber membrane filtration in which a flexible adhesive layer is arranged in a ring shape on the outside of a membrane bundle and in contact with the inner surface of a cylindrical case, sandwiched between non-flexible adhesive layers from both sides. module.