JPS61407A - Method for repairing porous hollow yarn membrane module - Google Patents

Abstract

PURPOSE:To certainly repair the leak place of a porous hollow yarn membrane module within a short time, by simple operation such that a wax rod is inserted in the opening part of a hollow yarn of which leakage is detected and broken off to leave and seal the chip of said wax rod in said opening part. CONSTITUTION:In a hollow yarn membrane module wherein a porous hollow yarn bundle is fixed by a sealing resin adhesive and the opening end part of each hollow yarn is exposed to the outer surface of the adhered and fixed end part, for example, when a hydrophobic polymer such as polyethylene is used as the hollow yarn, water is used as a liquid and this liquid is injected into the module from an injection port to detect the injection or blurring of water from the opening part of the hollow yarn. A rod 6 comprising a solid wax like substance is inserted into the opening part of the hollow yarn membrane 1 of which the leakage was detected and the insert part of the rod 6 is broken off, and left and sealed in the opening part 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a method for repairing a porous hollow fiber membrane module.

[Prior art]

Porous hollow fiber membranes are expected to be used in various fields, and membrane modules made of porous hollow fibers made of polypropylene, polyethylene, etc. have excellent water resistance and chemical resistance, and are suitable for medical applications, precision Used in a wide range of electronic industry applications, including food industry applications, physical and chemical applications, etc. For example, a sterile water production device that uses this module in ultra-precision applications to r-filter water and remove bacteria and fungi contained in the water, and a device that removes pyrogens from water to obtain pyrogen-free water. is a good example.

The most important problem in such a usage example of the module is the inspection of leak points from the primary side to the secondary side of the module due to defects in the hollow fibers, and how to repair them. That is, the existence of the leakage point is a serious problem in terms of the reliability of the ultra-precision f application module.

Generally, the most important cause of leakage points in modules is defects in the porous hollow fiber membrane itself.

In other words, porous hollow fibers are manufactured under strict process control, but since hundreds to tens of thousands of hollow fibers are usually used to manufacture the module, in reality, pinholes occur with probability. Defects in the porous hollow fiber membrane itself have become a major problem, as it is difficult to completely eliminate the occurrence of fiber defects, and fiber defects may also occur due to handling during module assembly. Therefore, finding and repairing leak points in the module due to defects in the hollow fibers (1) is an extremely important issue.

Conventionally, methods for repairing leak points in modules of this type include, for example, repairing the leak by press-fitting a resin adhesive into the leak point using a syringe, or repairing the leak by inserting a thin metal needle into the leak point to seal it. is often used. However, there are problems such as the repair operation is complicated, the repair takes a long time, and the repair effect is insufficient. Therefore, the improvement of the repair method for leak points is based on this module.” A-1)
□ooo□4.ヮ:z −)v @It is also very important from the aspect of improving reliability.

[Object of the Invention] Under these circumstances, the inventors of the present invention have conducted various studies on rational repair methods for the module, and as a result, they have arrived at the present invention.

[Structure of the invention]

That is, the present invention provides a hollow fiber membrane module in which the ends of a group of porous hollow fibers are fixed with a sealing resin adhesive, and the hollow fiber openings are exposed on the outer surface of the adhesively fixed ends. is characterized in that at least the tip of a rod made of a wax-like material (hereinafter referred to as a wax rod) is inserted into the hollow fiber opening where leakage is detected, and the inserted portion of the wax rod is folded and enclosed within the opening. The present invention relates to a method for repairing a porous hollow fiber module.

Next, the present invention will be explained in more detail with reference to the drawings.

FIG. 1 shows a state in which a wax rod is inserted into the hollow fiber opening and the inserted portion is folded and sealed.

FIGS. 2 and 3 show examples of basic cross-sectional views of the hollow fiber membrane module.

Figure 2 shows that both ends of the porous hollow fiber bundle (1) are fixed with a sealing resin adhesive (2X2'),
(3X3') indicates the opening of the hollow fiber, and (4) indicates the container. Figure 3 shows that the porous hollow fiber group (1) is bent into a U-shape, and the end face is fixed with the same sealing resin adhesive (2), and (3) shows the opening of the hollow fiber. ,
(4) indicates a container. Note that (5) in both Figures 2 and 3 shows the inlet for injecting liquid into the module, and there are multiple inlets and outlets for liquid that can be used as inlets depending on the end use of the module. In some cases, the other liquid inlets may be sealed with cocks or the like, and only one of them may be used as an injection port. When a hydrophobic polymer such as polyolefin is used as a porous hollow fiber membrane, if water is used as the liquid, the critical pressure will vary depending on the pore size and shape of the membrane, but it is usually does not pass water, and if there is a hollow fiber in the hollow fiber group that has a cut fiber or a pinhole in the membrane, water will gush out or seep out even at this level of pressure. That is, water is injected into the module from the injection port (5), and the hollow opening on the outer surface of the adhesive fixed end face (3X3' in FIG. 2 or (3) in FIG. 3) is injected into the module.
It detects water gushing or seeping out.

Similarly, when using membranes made of other materials, the weight is 1 to 5 kg.
In combination with a liquid that does not permeate the pores of the membrane up to an appropriate pressure of /cm', defective threads can be detected. The module is repaired by finding the location where the liquid is spouting or oozing, inserting a wax rod into the oozing location, and sealing the inserted portion of the rod into the opening.

Figure 1 shows this state. As shown in Figure 1, a wax rod (6) is inserted into the hollow opening (3) of the porous hollow fiber membrane (1), and the inserted part of the rod is Fold the opening (
3) Enclose the remainder inside.

The wax rod has a diameter that is equal to or greater than the inner diameter of the hollow fibers.

In consideration of ease of insertion into the hollow fiber opening, the tip of the rod is preferably sharp so that 1 to 5 mW of the tip can be inserted into the hollow portion. However, since the rod will be broken each time you use it, you will need to sharpen the tip each time you use it.

Although the wax rod (6) may be used as it is, it is more preferable from a practical point of view that it is shaped like a pencil lead and is embedded in wood or the like. That is, use a sharp knife to sharpen the tip of a wax stick like a pencil lead, as shown in (7) in Figure 3, and then insert it into the opening (3) for 1 to 5 mm. Then, by applying a slight stress in the lateral direction, it is broken within the opening (3) and sealed.

Since the wax rod (6) is made of a material with a smooth surface mainly made of wax, it is easy to insert the rod into the opening, and by applying a slight stress after insertion, it can be inserted into the opening. It is easy to enclose residuals.

With such a simple operation, mixing of retentate and permeate through the defective portion of the hollow fiber can be prevented.

After the repair work is completed, put 3 kg of A-rIL into the container again.
The repair is completed by injecting the liquid at a fluid pressure of 100 cm and confirming that there is no spouting or oozing of the liquid from the hollow opening.

As described above, according to the present invention, leakage portions can be detected and repaired in a short period of time and reliably in the minimum necessary number of locations with a very simple operation, which is extremely practical.

Next, the present invention will be explained in more detail with reference to Examples.

Example 15,000 porous hollow fiber membranes made of polyethylene (hollow opening diameter 270μ, wall membrane layer thickness 60μ) were bundled and bent into a U-shape, with a hollow opening near the tip. It was glued using polyurethane resin while keeping it in place. Next, the hollow fiber bundle was adhesively fixed to a cylindrical container made of polycarbonate resin using polyurethane resin, thereby producing 150 modules for producing sterile water. That is, the second
A module as shown in the figure was fabricated.

Water was injected into each module at a water pressure of 3.0 kg/am2, and the presence or absence of water spouting or oozing from the hollow opening of the module was examined. As a result, it was found that two modules had leak points.

That is, the test results were as shown in Table 1.

After marking the opening of the hollow fiber with the defect in the module to Table 1, the core is about 2 m1! The tip of a pencil-shaped rod made of a wax-like material with a sharpened tip was inserted approximately 3 mm in length, and the remaining portion was sealed to repair the damage. After making this module hydrophilic using approximately 70% ethanol, well water was heated to 5 A
The water was filtered at a rate of about 40*/min at a rate of 40*/min, and the water before and after filtration was examined for the presence of bacteria by a conventional method.

As a result, bacteria were detected in the sample water taken before F.
No bacteria were detected in the water after one lapse.

Next, a one-pass experiment was conducted under exactly the same conditions with module B left unrepaired.

As a result, bacteria were detected in both the water before and after the f-time.

The results are summarized in Table 2 below.

As shown in Table 2 above, the leak repair method according to the present invention was confirmed to be an excellent method.

〔effect〕

Membrane modules are typically used for water treatment of aqueous liquids. In this case, since the wax rod is hydrophobic, there is no melting or swelling of the wax rod, and the wax rod can be simply folded and sealed in the opening as in the present invention.
It has been found that under a water pressure of about 100 kg/cm", no liquid leaks from the opening of the hollow fiber in which the wax rod is broken and the remaining part is enclosed, and the liquid can withstand use sufficiently. In other words, as explained above, the present invention prevents leakage. The repair method is easy to operate and can be reliably repaired in a short period of time, making it an extremely effective repair method industrially.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing a wax rod inserted into a hollow opening, and FIGS. 2 and 3 are schematic cross-sectional views of a hollow fiber membrane module. In the figure, (1) is a porous hollow fiber membrane, (2) (2')
is resin adhesive for sealing, (3X3') is hollow fiber opening,
(4) shows the container, and (6) shows the tip of the stick made of the wax-like material left behind. #2 Diagram Qin 3 Diagram

Claims (1)

[Claims] Detecting leakage in a hollow fiber membrane module configured such that the ends of a group of porous hollow fibers are fixed with a sealing resin adhesive and the hollow fiber openings are exposed on the outer surface of the adhesively fixed ends. Repair of a porous hollow fiber membrane module, characterized by inserting at least the tip of a rod made of a solid wax-like material into the hollow fiber opening, and folding and enclosing the inserted portion of the rod in the opening. Method.