JPS60206413A - Method for repairing end surface of hollow yarn membrane separation module - Google Patents

Abstract

PURPOSE:To repair the contact inferior place of a module end surface without clogging the opening parts of hollow yarn membranes, by rotating a roller, which has a peculiar shape, having a repairing injection resin uniformly held thereto, in such a state that said roller is contacted with the other end surface of the module under pressure, while a fluid is sent into the hollow yarn membranes from the module end surface. CONSTITUTION:The surface of a roller made of rubber or a synthetic resin is processed so as to have reticulated or line like uniform uneven parts or uniform uneven parts are provided to the surfface of the roller by laminating nylon mesh thereto and a repairing injection resin is uniformly held to the recessed parts and the roller is rotated so as to be contacted with the injection resin surface of a module under pressure. Gas is sent into the hollow yarn membranes from the other end of the module. The repairing injection resin is contacted with the injection resin end surface of the module and detached from the recessed parts of the roller to fill adhesion inferior places. The resin is not contacted with the opening parts of the hollow yarn membranes and the resin is not further penetrated into the opening parts.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for repairing the end face of a hollow fiber membrane separation module, and more particularly to a method for completely and easily repairing leak spots on the end face of the module.

Hollow fiber membrane separation modules are widely used for processing various industrial liquids and gases, for medical purposes, and as equipment for producing ultrapure water.

In such a hollow fiber membrane separation module, for example, the hollow fiber membranes and the cylindrical case housing them are adhesively fixed at both ends with casting resin, and the hollow fiber membranes are bonded to each other on both end faces of the casting resin. It is known to have an opening.

When separating liquids using the above module, the stock solution is normally supplied through one open end of the hollow fiber membrane, the concentrated liquid flows out from the other open end, and the obtained permeate is placed in a cylindrical case. The permeate is discharged from the permeate outlet. In this case, the stock solution and concentrated solution must not leak to the permeate side, and if leakage occurs, the performance of the module will deteriorate and it will become unusable. The cause of this leak is often due to poor adhesion between the casting resin, hollow fiber membrane, and cylindrical case at the end, and therefore, it is necessary to repair this poor adhesion.

Conventionally, as the above-mentioned repair methods, repair methods using depressurization method (Japanese Patent Application Laid-open No. 54-135675) and repair methods using pressurization method (Japanese Patent Application Laid-open No. 54438874) have been proposed. Since the opening of the hollow fiber membrane is blocked during the process, the end must be further cut to open the hollow fiber membrane, which is very complicated and disadvantageous in terms of cost. Ta.

The present invention has been made to solve the drawbacks of the prior art, and provides a method for completely and easily repairing the end face of the snow-joule without clogging the opening of the hollow fiber membrane. .

That is, the present invention provides a method for repairing the end face of a module in which a plurality of parallel hollow fiber membranes are adhesively fixed to each other with casting resin so that the hollow fiber membranes are opened at the ends thereof. While blowing gas into the hollow fiber membrane, a roller, which is a repair member and has a uniform unevenness on its surface and a repair casting resin is held in the depressions, is rotated in pressure contact with the other end surface. The present invention relates to a method for repairing an end face of a hollow fiber membrane separation module, which comprises transferring casting resin onto the casting resin portion of the end face.

In the present invention, a gas such as pressurized gas or air is blown into the hollow fiber membrane from one end surface of the module, and a repair casting resin is transferred to the other end surface using a unique repair member. It is used to repair defects in adhesion on the end face of
It is best to blow air at a pressure of 2 kg / cA, 0,5
kg/cA or less, there is a risk that the repair casting resin may enter the opening of the hollow fiber membrane.

The repair member used in the present invention is a roller that has uniform unevenness on its surface and is held in a state in which repair casting resin can be uniformly transferred to the depression, and the roller is pressed against the module end face. By rotating it, the repair casting resin can be transferred to the end face of the casting resin.

Such rollers include rollers made of rubber, synthetic resin, metal, etc. whose surface is processed to have uniform unevenness such as mesh or linear, or meshes made of nylon, polyester, etc. on the surface of the roller. You can use the pasted one. ] The pinch of the concave and convex portions on the surface of the roller may be anything that can hold the repair casting resin in the concave portions and transfer the repair casting resin to the end face of the casting resin of the module. Although it varies depending on the inner diameter of the membrane, the inner diameter is 20 to 3,000 μm1 usually 500 to 1,500 μm.
, film thickness is 5-1,000μm, usually 100-500μm
When applying the present invention to a hollow fiber membrane with a diameter of 20 to
The thickness used is about 300 μm, preferably about 70 to 130 μm. If the pitch is too small, it will be difficult to separate the repair casting resin held in the recess from the recess when it is pressed against the end face of the module, making it difficult to transfer the resin to the end face of the module. Even if gas is blown into the opening of the hollow fiber membrane, the repair casting resin may enter the opening, which is not preferable. Although the depth of the recess varies depending on the amount of repair casting resin required, it is usually preferably 50 to 200 μm.

Furthermore, from the viewpoint of workability during transfer, it is preferable to set the diameter and length of the roller so that the entire surface to be repaired comes into contact with the roller by rotating the roller once or less.

In order to produce the repair member of the present invention, the repair casting resin can be directly held in the recesses on the surface of the roller described above, but from the viewpoint of uniform retention of the resin, it is preferable to produce it by the following operation. .

That is, first, a repair casting resin is uniformly applied to the surface of a sheet-like object so that the resin layer has a thickness of about 50 to 200 μm. The above-mentioned sheet-like material may be any material as long as its surface is smooth and a uniform resin layer can be provided in a removable manner, such as plastic sheets made of polypropylene, polyethylene, polytetrafluoroethylene, polyvinyl chloride, etc. used. Next, by rotating the roller several times on the resin layer provided on the sheet-like material, a repair member can be obtained in which the repair casting resin is transferred and held in the recesses on the roller surface.

In addition, the repair casting resin used in the present invention may be any resin that can be uniformly held so that it can be transferred to the recesses on the roller surface, and has a viscosity of 200 to 10,000 cp at the temperature during use, usually at room temperature. , preferably 50
0 to 2.000 cpO can be used.

If the viscosity is outside the above range, it will be difficult to uniformly hold a predetermined amount of resin in the recess, and furthermore, the resin will enter the hollow fiber membrane opening when the repair member is pressed against the end face of the cast resin of the module. There is a fear. The material of the repair casting resin is not particularly limited, but it is preferable to use the same type of casting resin as the module, such as epoxy resin or urethane resin.

By pressing and rotating the repair member formed in this way against the end face of the casting resin, the repair casting resin held in the recess on the surface of the roller comes into contact with the end face of the casting resin of the module and is released from the recess. It is transferred to the end face and filled in the defective adhesion area. On the other hand, at the opening of the hollow fiber membrane, the repair casting resin is held in the recess without contacting the opening, and gas is blown to prevent the resin from entering the opening. Completely preventable.

As described above, according to the present invention, while gas is blown into the hollow fiber membrane from the end face of the module, a roller of a unique shape that evenly holds a repair casting resin as a repair member is pressed against and rotated on the other end face of the module. Therefore, the above-mentioned repair casting resin can be successfully transferred to the end face of the casting resin without blocking the hollow fiber membrane opening, and there is an advantage that defective adhesion on the end face of the module can be completely and easily repaired.

Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 3,700 polysulfone hollow fiber membranes with an inner diameter of 500 μm and a membrane thickness of 250 μm were housed in a vinyl chloride cylindrical case with an inner diameter of 77 mm and a length of 1,077 mm, and both ends were adhesively fixed with an epoxy resin composition. After the resin was cured, both ends of the hollow fiber membrane were cut to open the hollow fiber membrane to obtain a hollow fiber membrane separation module.

When a leak test was conducted by supplying pressurized gas to the outside of the hollow fiber membrane of this module, it was found that the pressure of the pressurized gas decreased and a leak point occurred.

Therefore, first, an epoxy resin composition with a viscosity of 1 and 0OOcp was uniformly applied as a repair casting resin onto a polypropylene sheet so that the resin layer had a thickness of 70 to 150 μm, and then a pitch of about 127 μm was applied to the surface. About 7
Roller (diameter 40 mm, length 100 mm) made of 5 μm polyester mesh (200 mesh)
was rotated several times on the resin layer to transfer and retain the resin in the recesses on the roller surface to produce a repair member.

After that, air is introduced into the hollow fiber membrane from one end of the module.
．． While blowing air at a pressure of 5 kg/cIa, the repair member was rotated in pressure contact with the other end surface of the module to transfer the resin to the end surface of the cast resin, and then the blowing of air was stopped and the resin was cured.

A leak test was conducted again on the module whose end face had been repaired as described above, but no leaks were observed at all. Furthermore, the openings of the hollow fiber membranes were not blocked in any way.

patent applicant Nitto Electric Industry Co., Ltd. Representative Sanbe Hijikata

Claims (1)

[Claims] In a method of repairing the end face of a module in which the membranes are adhesively fixed to each other with casting resin so that the hollow fiber membranes open at the ends of a plurality of hollow fiber membranes bundled in parallel, The repair casting resin is applied by pressing and rotating a roller having uniform unevenness on the surface and holding the repair casting resin in the recesses as a repair member while blowing gas to the other end of the roller. A method for repairing an end face of a hollow fiber membrane separation module, comprising transferring the resin onto the cast resin portion of the end face.