JP3184631B2 - Leak inspection method for hollow fiber membrane module - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for inspecting a leak of a hollow fiber membrane module having a large number of hollow fiber membranes.

[0002]

2. Description of the Related Art Conventionally, there is a hollow fiber membrane module as shown in FIG. That is, reference numeral 100 denotes a hollow fiber membrane module main body. In this hollow fiber membrane module 100, a bundle of a large number of hollow fiber membranes 102 is inserted in a loop (U-shape) into a case 101 open at both ends. The end of each hollow fiber membrane 102 is sealed and fixed at one opening end of the case 101 with a potting agent 103, and the end is cut to open the end of the hollow fiber membrane 102 to open the end of the hollow fiber membrane 102. Is formed. Various gases and liquids are filtered through the hollow fiber membrane 102, and the filtered fluid flows out from the hollow fiber membrane opening end surface 104.

[0003] Such a hollow fiber membrane module 1
As a method of inspecting the leak of the 00, there is a method of inspecting the leak by using, for example, an inspection apparatus shown in FIG. 4 (see Japanese Patent Publication No. 2-14084). Therefore, a method of inspecting the leak of the hollow fiber membrane module 100 will be described with reference to FIG. 5 which is a simplified and schematic diagram of the inspection apparatus shown in FIG.

First, a simplified inspection apparatus 200 shown in FIG. 5 will be described. In the inspection device 200, the hollow fiber membrane module 100 is roughly held by a holder 201 on the hollow fiber membrane opening end face 104 via an O-ring 202,
Therefore, the hollow fiber membrane open end face 104 is completely shut off from the outside air by the action of the O-ring 202 provided on the holder 201. Then, the holding part of the hollow fiber membrane opening end face 104 of the holder 201 and the vacuum pump 20 as a suction means are provided.
A particle counter 204 for measuring the number of fine particles having various particle diameters, which contains 3, is connected through a pipe 205.

[0005] The method of inspecting the leak of the hollow fiber membrane module 100 by the inspection apparatus 200 is as follows. A gas K containing fine particles of a predetermined size flows into the hollow fiber membrane module 100 from the outer surface side of the hollow fiber membrane 102, and filtered gas 206, which is a filtered gas sucked from the hollow fiber membrane opening end face 104, is subjected to a particle counter 204. And the number of fine particles of a predetermined size in the filtration 206 is measured.

That is, the filtration air 2 passes through the hollow fiber membrane 102.
When the air is discharged from the opening end face 104 of the hollow fiber membrane, the number of fine particles passing through the hollow fiber membrane 102 and the defective part of the hollow fiber membrane module 100 is measured to determine the presence or absence of the defective part. The judgment is made to check the leakage of the hollow fiber membrane module.

[0007]

However, in the case of the above-described conventional method for inspecting a leak of the hollow fiber membrane module 100, the hollow fiber membrane module 100 sucks the vacuum fiber from the opening end face 104 side and depressurizes the hollow fiber membrane module with the particle counter 204. 102,
Since the number of fine particles passing through the defective portion of the hollow fiber membrane module 100 is measured, if the defective portion of the hollow fiber membrane 102 is in the middle of the bundle of hollow fiber membranes 102, a pinhole (defective portion) is formed. The side surface of the other hollow fiber membrane 102 is blocked, the hollow fiber membrane 102 having a defect is crushed in the middle,
In addition, as shown in FIG. 7, there is a defect that a defective portion at a portion where the hollow fiber membranes are in contact with each other (arrow A) cannot be detected.

[0008] Further, as shown in FIG. 6, if a place where the bundle of hollow fiber membranes 102 is dense (arrow B) occurs in the bundling method of the hollow fiber membranes 102, the gas becomes difficult to ventilate, so that the gas drifts. Arrow C) occurs. As a result, the flow of gas into the defect is reduced, and the defect may be trapped as a defect smaller than the original defect.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a method for inspecting the leak of a hollow fiber membrane module which can improve the reliability of the leak inspection. Is to do.

[0010]

In order to achieve the above object, according to the present invention, a bundle of a large number of hollow fiber membranes is inserted into a case, and each hollow fiber membrane is inserted at an open end of the case. The gap between the hollow fiber membranes and the gap between each hollow fiber membrane and the case was sealed and fixed with a potting agent, and a gas containing fine particles of a predetermined size was passed through the hollow fiber membrane and passed through the hollow fiber membrane. In the method of measuring the number of fine particles having a predetermined size and inspecting the leak of the hollow fiber membrane module, the gas is caused to flow into the hollow portion of each hollow fiber membrane from the open end face side of the hollow fiber membrane, The gas flows out through the membrane wall of the membrane,
The method is characterized in that the gas is guided to the outside of the case while keeping an interval between the hollow fiber membranes by the gas outflow pressure, and the number of fine particles having a predetermined size that has passed is measured.

[0011]

In the method for inspecting a leak of a hollow fiber membrane module having the above structure, a gas containing fine particles having a predetermined size is caused to flow into the hollow portion of each hollow fiber membrane from the opening end face side of the hollow fiber membrane. Since the gas flows out through the membrane wall of each hollow fiber membrane, for example, even if the hollow fiber membranes are in contact with each other, the gas is contacted by the outflow pressure when the gas flows out through the hollow fiber membrane wall. Since the space between the hollow fiber membranes in the existing portion is widened, the defective portion is not closed.

Even if the hollow fiber membranes are bundled in a dense place, the outflow pressure increases the space between the hollow fiber membranes in the dense part, so that a drift may occur as in the prior art. Disappears. As a result, the gas flow becomes smooth, and the original defect is not captured as a small defect.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIG. 1 shows an inspection apparatus used for a leak inspection method of a hollow fiber membrane module according to one embodiment of the present invention, and FIG. 2 shows a hollow fiber membrane module to be subjected to a leak inspection.

First, the hollow fiber membrane module to be subjected to the leak test shown in FIG. 2 will be described. In this hollow fiber membrane module 1, a large number of hollow fiber membranes 2 are bundled to form a loop (U shape), and the hollow fiber membrane bundle 3 is inserted into a case 4 having both ends opened. The gap between each hollow fiber membrane 2 and the gap between each hollow fiber membrane 2 and the case 4 are sealed and fixed with a potting agent 5 at the open end, and the hollow fiber membrane 2 sealed and fixed with the potting agent 5 The terminal and the hardened potting agent 5 are cut together, and the end of each hollow fiber membrane 2 is opened to form a hollow fiber membrane open end face 6. Various gases and liquids are filtered through the hollow fiber membrane 2, and the filtration is performed. The discharged fluid flows out from the opening end face 6 of the hollow fiber membrane.

Hereinafter, a method for inspecting a leak of a hollow fiber membrane module according to one embodiment of the present invention will be described using the hollow fiber membrane module 1 having the above configuration.

First, when air, which is gaseous, is pressurized into the hollow fiber membrane module 1 from the hollow fiber membrane opening end face 6 side by pressurizing means such as a pressurizing pump, the air flows into each hollow fiber membrane 2. It flows into the hollow part 7 from the opening of the terminal. The air that has flowed in flows out of the hollow portion 7 through the membrane wall 8 having micropores, and the outflow pressure of the air opens the space between the hollow fiber membranes 2 so that the air flows into the other opening of the case 4. Guided to section 9. At this time, the fine particles contained in the air are filtered by the fine holes in the membrane wall 8 of the hollow fiber membrane 2, and the fine particles larger than the outer diameter of the fine holes remain in the hollow portion 7. Is discharged out of the case 4 through the other opening 9.

However, when the hollow fiber membrane 2 has a defective portion such as a pinhole, the hollow fiber membrane 2 is pressurized from the hollow portion 7, so that the defective portion such as the pinhole spreads and is fixed. The air containing particles of a predetermined size and passing through a defective portion such as a pinhole passes through the other opening 9 of the case 4.
More out of the case 4. In addition, when a gap is formed between the cured potting agent 5 and the hollow fiber membrane 2, between the cured potting agent 5 and the case 4, or when fine holes are formed through the layer of the cured potting agent 5. Similarly, air containing fine particles of a predetermined size flows out of the case 4 from the other opening 9 of the case 4 through the gaps and holes.

Thus, the other opening 9 of the case 4
When the air that has flowed out of the device is guided to a particle counter that measures the number of particles having various particle diameters, if a leak is present and the air that has flowed out contains particles of a predetermined size, a particle counter is used. The particle size and the number of the fine particles having a predetermined size are measured. At this time, the particle size of the fine particles having a predetermined size measured is the same as the size of a defective portion such as a pinhole.

On the other hand, if there is no leak,
The number of the fine particles measured by the particle counter is only the fine particles having a particle diameter passing through the fine pores of the membrane wall 8 of the hollow fiber membrane 2, and when the fine pores of the membrane wall 8 of the hollow fiber membrane 2 are sufficiently small. Since only particles having a detection sensitivity lower than the particle counter are discharged, the number of particles measured is zero. Therefore, the presence or absence of a leak in the hollow fiber membrane module can be easily determined by counting with a particle counter.

According to this method, since it becomes a substitute test for the sterilization property of the hollow fiber membrane 2, the filtration performance can be inspected in a dry state.

In the leak inspection method of the present invention, air is caused to flow into the hollow portion 7 of each hollow fiber membrane 2 from the hollow fiber membrane opening end face 6 side, and air is flown into the membrane wall of each hollow fiber membrane 2. 8 and each hollow fiber membrane 2
The air is guided to the outside of the case 4 through the other opening 9 of the case 4 while keeping an interval therebetween, and the number of fine particles such as dust contained in the filtered air is measured. Therefore, a defective portion such as a pinhole of the hollow fiber membrane 2
The air flows out of the hollow portion 7 of the hollow fiber membrane 2 through the membrane wall 8 even if the side surface of the other hollow fiber membrane 2 blocks a defect such as a pinhole. The gap between the hollow fiber membrane 2 having the defect and the other hollow fiber membrane 2 covering the defect is increased by the outflow pressure at that time, and the side of the other hollow fiber membrane 2 is formed by the defect. Blocking can be prevented, and the presence or absence of a defective portion can be reliably determined.

Further, even if the hollow fiber membrane 2 having a defective portion is crushed in the middle, air flows into the hollow portion 7 of the hollow fiber membrane 2, so that the shape of the crushed portion due to the inflow pressure is reduced. Can be undone. Therefore, the air passes through the defective portion, and the presence or absence of the defective portion can be reliably determined.

Further, as shown in FIG. 7, even when the hollow fiber membrane 2 has a defective portion at the portion in contact with each other (arrow A in the figure), the portion contacted by the outflow pressure is used Since the interval between the hollow fiber membranes 2 is increased, the presence or absence of a defective portion can be reliably determined.

Further, as shown in FIG. 6, even if there are dense places depending on how the hollow fiber membranes 2 are bundled and it is difficult to ventilate the hollow fiber membranes 2, the dense part of the hollow fiber membranes 2 is not affected by the outflow pressure.
Since the space between them is increased and ventilation is facilitated, air drift does not occur unlike the related art. Therefore, the outflow of air through the defective portion in the potting portion 10 or the like does not decrease, and the defect is not caught as a defect smaller than the original defect. Therefore, the size of the defective portion can be accurately determined.

From the above, the reliability of the leak test can be improved (the leaking hollow fiber membrane module has a particle counter value about two digits higher than the normal hollow fiber membrane module).

In the above-mentioned leak inspection method, air is introduced into the hollow portion 7 of each hollow fiber membrane 2 by a pressurizing pump. The air may flow into the hollow portion 7 without using the pressure pump.

Next, a description will be given of an inspection apparatus 11 as an embodiment used for a leak inspection of the hollow fiber membrane module of the present invention shown in FIG.

This inspection apparatus 11 is generally composed of a mounting member 12 of the hollow fiber membrane module 1, a pressure pump 13, and a particle counter 14 for measuring the number of fine particles having various particle diameters. , Hollow fiber membrane module 1
Are fixed to the mounting member 12.

The mounting member 12 has a cylindrical shape with a bottom, and holds the hollow fiber membrane opening end face 6 which is both ends of the case 4 and the other opening 9. In addition, the bottom portion 12A of the cylindrical mounting member 12 having the bottom at both ends is substantially at the center of the bottom portion 12A.
A has a hole 12B penetrating through A. And
The hollow fiber membrane opening end face 6 of the hollow fiber membrane module 1 and the other opening 9 of the case 4 are completely shut off from the outside air by the action of the O-rings 15 provided on the respective mounting members 12.

The hole 1 of the mounting member 12 provided on the pressure fiber pump 13 and the hollow fiber membrane opening end face 6 side of the hollow fiber membrane module 1
2B is connected by a pipe 16. A particle counter 14 having a built-in suction means and a mounting member 12 on the other opening 9 side of the case 4 of the hollow fiber membrane module 1 are connected by a pipe 17. Further, the pipes 16 and 17 are provided with pressure gauges 18 and 19, respectively.

In order to inspect the leak of the hollow fiber membrane module by the inspection device 11, both ends of the hollow fiber membrane module 1 are fixed by the mounting members 12, and the pressure pump 13 contains fine particles of a predetermined size. Gas 16
Then, the filtered air flowing out of the other opening 9 of the case 4 is sent to the hollow fiber membrane opening end face 6 through the hole 12 </ b> B of the mounting member 12, and the suction means in the particle counter 14 is activated to operate the mounting member. 12 holes 12B
And through the pipe 17 into the particle counter 14. Then, the amount (number) of dust (fine particles having a predetermined size) contained in the air filtered by the particle counter 14 is measured, and a leak test is performed. After the measurement is completed, the hollow fiber membrane module 1 is removed from the mounting member 12, and a series of leak inspection operations is completed.

The hollow fiber membrane module 1 subjected to this inspection was
Since fine particles are captured in the hollow portion 7 of each hollow fiber membrane 2, the fine particles are inspected and absorbed from the opening end face 6 side of the hollow fiber membrane or subjected to ultraviolet sterilization or autoclaving before shipment.

Therefore, the number (particles) of fine particles having a diameter of 0.2 μm or more, that is, the particle value in the filtered air is measured by the above-described inspection apparatus 11 by the above-described method for inspecting the leak of the hollow fiber membrane module according to the present invention. However, the result was shown in Table 1 below as a result of an investigation as to what would happen with the particle value inspected by the conventional method.

[0034]

[Table 1] As can be seen from Table 1 above, even if the particle value is 0 in the conventional method, it is 2 in the leak inspection method according to the present invention.
The number is counted as 1 to 51, and the presence or absence of a defective portion is reliably detected. In addition, since the leak inspection method according to the present invention is counted more than the conventional method even at other particle values, it can be seen that the reliability of the leak inspection is improved.

In addition, the presence / absence of bubbles was compared and investigated in the hollow fiber membrane module 1 in water between the leak inspection method according to the present invention and the conventional method. The results are shown in Table 2 below.

[0036]

[Table 2] In Table 2 above, the mark ○ indicates that bubbles were generated in water. As can be seen from Table 2, even in the case where no bubble is generated in the conventional method (marked by “x”), the bubble is generated in the leak inspection method according to the present invention, and the presence or absence of a defective portion is reliably determined. Has been detected.

From the above results, it can be seen that the leak inspection method according to the present invention more accurately inspects the hollow fiber membrane module for the presence or absence of a defective portion than the conventional method.

In the inspection device 11, each hollow fiber membrane 2
Although the example using the pressurizing pump 13 to flow air into the hollow portion 7 has been described, the particles for measuring the number of particles of a predetermined size as described in the above-described leak inspection method are described. Since the suction means is provided in the counter 14, air can flow in without using a pressurizing pump. Therefore, the inspection device 11A without the pressurizing pump as shown in FIG. 3 may be used. (Main inspection device 1
1A is a basic configuration. ). In this inspection device 11A, if the dust particles are too large, they will not flow into the hollow portions 7 of the respective hollow fiber membranes 2, so that a coarse prefilter 20 for removing large dust is provided.

[0039]

The present invention has the above-described structure and operation, and allows a gas containing fine particles of a predetermined size to flow into the hollow portions of the hollow fiber membranes from the opening end face side of the hollow fiber membranes, thereby allowing the gas to flow therethrough. The gas is caused to flow out through the membrane wall of each hollow fiber membrane, and the gas is guided to the outside of the case while leaving an interval between the hollow fiber membranes by the outflow pressure of the gas. Since the number of fine particles is measured, for example, even if the hollow fiber membrane has a defective portion such as a pinhole in the portion in contact with each other, the portion in contact with the outflow pressure may have a defect. Since the interval between the hollow fiber membranes is increased, the presence or absence of a defective portion can be reliably determined.

In addition, even if there are dense places depending on how the hollow fiber membranes are bundled and the air is difficult to ventilate, the space between the hollow fiber membranes in the dense part is widened by the above-mentioned outflow pressure, so that the air is easily ventilated. Therefore, the drift does not occur unlike the related art. Therefore, the outflow of gas through the defective portion in the potting portion and the like does not decrease,
It is not caught as a defect smaller than the original defect. Therefore, the size of the defective portion can be accurately determined.

As described above, the reliability of the leak test of the hollow fiber membrane module can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of an inspection apparatus to which a leak inspection method for a hollow fiber membrane module according to one embodiment of the present invention is applied.

2 (a) is a side sectional view of the hollow fiber membrane module of FIG. 1, and FIG. 2 (b) is a left side view of FIG. 2 (a).

FIG. 3 is a schematic view of an inspection device having a basic configuration of the inspection device for a hollow fiber membrane module of FIG. 1;

FIG. 4 is an overall schematic diagram of an inspection apparatus to which a conventional method for inspecting a leak of a hollow fiber membrane module is applied.

FIG. 5 is a schematic diagram of a main part of the inspection device of FIG. 4;

FIG. 6 is a side sectional view of the hollow fiber membrane module shown in FIGS. 4 and 5;

FIG. 7 is a schematic diagram showing a state where hollow fiber membranes are in contact with each other.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hollow fiber membrane module 2 Hollow fiber membrane 3 Hollow fiber membrane bundle 4 Case 5 Potting agent 6 Hollow fiber membrane opening end face 7 Hollow part 8 Membrane wall 9 Opening part 10 Potting part 11, 11A Inspection device 12 Mounting member 12A Bottom part 12B hole 13 Pressure pump 14 Particle counter 15 O-ring 16, 17 Piping 18, 19 Pressure gauge 20 Pre-filter

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields investigated (Int. Cl. ⁷ , DB name) G01M 3/00 B01D 63/02 B01D 65/10 G01N 15/08

Claims (1)

(57) [Claims] 1. A bundle of a number of hollow fiber membranes is inserted into a case, and a gap between each hollow fiber membrane and a gap between each hollow fiber membrane and the case are sealed with a potting agent at an open end of the case. A gas containing fine particles of a predetermined size is passed through the hollow fiber membrane of the fixed hollow fiber membrane module, and the number of fine particles of a predetermined size passing through the hollow fiber membrane is measured to reduce the leak of the hollow fiber membrane module. In the inspection method, the gas flows into the hollow portion of each hollow fiber membrane from the opening end face side of the hollow fiber membrane, and the gas flows out through the membrane wall of each hollow fiber membrane. A method for inspecting a leak of a hollow fiber membrane module, wherein a gas is guided to the outside of the case while keeping an interval between hollow fiber membranes, and the number of fine particles having a predetermined size passed through is measured.