JP3319825B2 - Defect detection 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 detecting a defect in 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. Reference numeral 100 denotes a hollow fiber membrane module.
Inserts a bundle of a large number of hollow fiber membranes 102 in a U-shape into a cylindrical case 101 having both ends opened,
At one open end of the case 101, a gap between the hollow fiber membranes 102 and each hollow fiber membrane 102 and the case 101.
A sealing material 103 is filled and fixed therebetween, and the end is cut to form a hollow fiber membrane opening end face 104 that opens the end of each hollow fiber membrane 102. Then, various gases and liquids are filtered through the hollow fiber membrane 102, and the filtered various gases and liquids flow out from the hollow fiber membrane opening end surface 104.

[0003] Such a hollow fiber membrane module 1
Regarding 00, there are the following methods for detecting the defect. First, the atmosphere A is passed through the hollow fiber membrane module 100 through the opening of the case 101 opposite to the hollow fiber membrane opening end face 104. At this time, dust in the air A does not flow out from the hollow fiber membrane 102A having no defect (see the arrow B in the figure), and the air from the hollow fiber membrane 102B having the defective portion W such as a cut in the hollow fiber membrane is in the air A. Dust flows out (see arrow C). As described above, a method of detecting a defect in which the air A is passed through the hollow fiber membrane module 100 to detect the dust in the air A flowing out of the defective portion is generally used (see FIG. 3). Other defect detection methods are disclosed in JP-A-53-134776 and JP-A-59-19833.
No. 6 discloses a method.

[0004]

However, in the case of the above-described conventional method for detecting a defect of a hollow fiber membrane module using the above-mentioned floating dust in the normal atmosphere A, the floating fiber module floats in the air A. Different detection results may be obtained due to the time difference between the morning when the number of dust is small and the afternoon when the number of dust floating due to human activity increases,
There is a problem that the reliability of defect detection is low.

Further, the particle size distribution of dust in the atmosphere A is concentrated to 0.2 μm or less, and it is difficult to detect the dust due to the small particle size, and it is necessary to detect a small particle size. Therefore, a highly accurate and expensive inspection device is required.

Further, dust having a particle diameter of 0.2 μm or more, which is relatively easy to detect, has a defect in the hollow fiber membrane module 100 as a whole because the probability of occurrence (concentration) in the atmosphere A is low. However, it was not possible to detect where the hollow fiber membrane module 100 was defective.

Therefore, for example, smoke of tobacco or incense having a particle diameter of 0.2 μm or more that can be easily detected may be used. The tobacco or incense smoke mainly has a particle diameter of 0.1 to 0.5 μm.
m, the hollow fiber membrane module 100
What is necessary is just to observe the tobacco and incense smoke flowing out of the defective part. However, cigarettes and incense smoke add an unpleasant odor to the hollow fiber membrane module 100 and change the hollow fiber membrane 102 to a brownish brown color, and thus cannot be put to practical use as a detection method. In JP-A-53-134776, the pressurized gas flows out of the normal hollow fiber membrane, and is determined from the difference in the flow rate of the pressurized gas. Therefore, it is difficult to adjust the flow rate for visualizing the pressurized gas.

In Japanese Patent Application Laid-Open No. 59-198336, particles contained in a liquid passing through a defective portion are detected by a light scattering type particle detector which is a particle detector provided downstream of a furnace. Because of the detection, it is not possible to specify the defect location.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art. It is an object of the present invention to improve the reliability of defect detection and to detect the position of a hollow fiber. An object of the present invention is to provide a method for detecting a defect of a membrane module.

[0010]

In order to achieve the above object, according to the present invention, a large number of hollow fiber membranes inserted into a case are closed at the end of the opening of the case. Wherein the gap between each hollow fiber membrane and the gap between each hollow fiber membrane and the case are sealed and fixed with a sealing material in a state in which the hollow fiber membrane module is opened. A gas in which fine particles of a predetermined size are dispersed at a constant concentration is passed through the inside of the hollow fiber membrane.
-Inactive by scanning light and passing through the hollow fiber membrane module
Scattered light due to the collision of the laser light
The defect position information is detected by a camera .

[0011]

According to the method for detecting a defect in a hollow fiber membrane module having the above-described structure, the defect is detected by a gas in which inert particles of a predetermined size are dispersed at a predetermined concentration, so that the defect flows out of the defective portion of the hollow fiber membrane module. The number of inert particles to be detected stabilizes without being affected by the detection time zone and surrounding conditions. Therefore, the presence or absence of a defect can be reliably determined, and the reliability of defect detection is improved.

In addition, the presence or absence of a defect can be reliably determined as described above, and the laser beam is scanned in the plane direction of the open end face of the hollow fiber membrane.
The scattered light generated by the light colliding with the inert particles
By detecting with a camera, the position of a defective portion can also be detected.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIG. 1 shows a method for detecting a defect in a hollow fiber membrane module according to one embodiment of the present invention.

First, a hollow fiber membrane module to be subjected to a defect detection method will be described with reference to FIG. In this hollow fiber membrane module 1, a large number of hollow fiber membranes 2 are bundled into a U-shape, and the hollow fiber membrane bundle 3 is inserted into a cylindrical case 4 having both ends opened. The end is formed at one open end of the case 4 at the gap between the hollow fiber membranes 2 and the hollow fiber membranes 2.
The sealing material 5 is filled and sealed between the case 4 and sealed, and the end of each of the hollow fiber membranes 2 sealed and fixed by the sealing material 5 and the cured sealing material 5 are cut together to form each hollow. The end of the fiber membrane 2 is opened to form a hollow fiber membrane open end face 6, and various gases and liquids are filtered through the hollow fiber membrane 2, and the filtered gases and liquids are passed through the hollow fiber membrane open end face. It flows out of 6.

Hereinafter, a method for detecting a defect in 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.

The method of detecting a defect of the hollow fiber membrane module 1 is performed by using the case 4 on the opposite side of the hollow fiber membrane open end face 6.
Air A in which inert particles as fine particles of a predetermined size are dispersed at a constant concentration from the opening of the hollow fiber membrane module 1
Pass inside. At this time, the inert particles do not flow out of the hollow fiber membrane 2 having no defect, and the inert particles flow out of the hollow fiber membrane 2 having a defective portion such as a cut of the hollow fiber membrane 2. The air A in which the inert particles are dispersed at a constant concentration as described above is passed through the hollow fiber membrane module 1 and the air A flowing out of the defective portion
It is to detect inert particles in it.

Here, the air A in which the above-mentioned inert particles of a predetermined size are dispersed at a constant concentration will be described in detail. The predetermined size refers to a particle size of 0.1 to 1.0 μm, preferably 0.15 to 0.5 μm, more preferably 0.2 to 0.5 μm.
It has a distribution of 4 μm. 0.1-1.0μ above
The value of m is such that an aerosol constant generator, which is generally known as a device for dispersing particles having a uniform diameter in air A, has a particle diameter of 0.
This value is used because it is from 1 to 1.0 μm. In addition, since it is known that the diameter which can be relatively easily detected must be 0.15 to 0.2 μm or more as described above, the diameter is 0.15 to 0.5 μm, preferably 0.2 to 0.4 μm. And Incidentally, the numerical value varies depending on the device for dispersing the inert particles to a certain concentration and the diameter of the hole formed in the side surface of the hollow fiber membrane 2, and is not particularly limited to the above numerical value. It is sufficient that the diameter is equal to or larger than the diameter that is easy to perform.

The reason why the inert particles are used is that the hollow fiber membrane module 1 is not smelled or colored unlike tobacco or incense.

There are countless such inert particles of a predetermined size, but in practice, particles of fatty acids such as stearic acid designated as food additives and polystyrene compatible with the Food Sanitation Law are practically used. Particles and the like are desirable. Then, the stearic acid is heated and melted, and is sprayed in a mist into a gas, that is, air A as a gas to disperse stearic acid particles having an average particle diameter of 0.3 μm in the air A. Is widely known. As for polyethylene, a device for dispersing polystyrene particles having a particle size distribution of 0.1 to 0.5 μm in air A is commercially available. Of course, substances other than the above stearic acid and polystyrene may be used.

Next, a defect position detecting device for detecting a defect position of a hollow fiber membrane module by detecting a position of an inert particle passing through the hollow fiber membrane module 1 by the above defect detection method is shown in FIG. Description will be made based on a).

In this defect position detecting device, the laser beam 7 scans the laser beam 7 in the plane direction of the hollow fiber membrane opening end face 6 and the laser beam 7 collides with the inert particles N via the lens 9. A camera 11 for detecting scattered light generated as a defect position information, and for facilitating detection of scattered light when the scattered light is dark, that is, when detecting small inert particles, or when the sensitivity of the camera 11 is low. And an image intensifier (high-sensitivity doubler) 10 provided in the camera.

The method for detecting the position of a defect in the hollow fiber membrane module 1 by the defect position detecting device is as follows. Of inert particles dispersed at a constant concentration. Then, the camera 11 detects the scattered light of the inert particles N from the defective portion W, passes through the hollow fiber membrane 2, and exits from the hollow fiber membrane opening end face 6. The image of the camera 11 at the time of this detection is as shown in FIG. 2B, and the position of the defective portion of the hollow fiber membrane module 1 can be specified.

According to the defect detection method for the hollow fiber membrane module, the defect is detected by air A in which inert particles of a predetermined size are dispersed at a constant concentration. The number of inert particles flowing out is
It is stable without being affected by the detection time zone and surrounding conditions. Therefore, the presence or absence of a defect can be reliably determined, and the reliability of defect detection is improved.

In addition, since the presence or absence of a defect can be reliably determined as described above, the position of a defective portion can be detected. The position of the defective portion is specified by the defect position detecting device.

Further, by keeping the concentration of the inert particles constant, the number of the defective parts and the distinction between the breakage and the tearing of the hollow fiber membrane can be distinguished from the number of the inactive particles flowing out from the defective part. Available.

The inert particles have a particle size of 0.1 to
By setting the distribution to 1.0 μm, preferably 0.15 to 0.5 μm, and more preferably 0.2 to 0.4 μm, the particle diameter of the inert particles flowing out of the defect is 0.2 μm.
Since it has a diameter as large as μm or more, that is, contains a diameter that is easy to detect at a constant concentration, the presence or absence of a defect can be easily recognized, and the position of the defect can be more easily specified.

Further, since the diameter which is easy to detect is included at a constant concentration, it can be detected even by an inexpensive low-accuracy detecting device.

Further, since the inactive particles are detected from the position of the defect, there is no need to adjust the gas, that is, the flow rate of the gas, as in Japanese Patent Application Laid-Open No. 53-134776.

In the above embodiment, a hollow fiber membrane module in which a bundle of a large number of hollow fiber membranes is inserted into a case in a U-shape has been described as an example. However, the present invention is not limited to this. The bundle of membranes is inserted straight into the case, and as a cross-flow type hollow fiber membrane module, no defects are detected at the end face of the hollow fiber membrane opening, and defects are detected at the transmission opening, which is the secondary side opening. The same can be applied to an object.

[0030]

According to the present invention, according to the above-described method for detecting a defect in a hollow fiber membrane module, the defect is detected by a gas in which inert particles of a predetermined size are dispersed at a constant concentration. The number of inert particles flowing out of the defective portion of the module is stabilized without being affected by the detection time zone and surrounding conditions. Therefore, the presence or absence of a defect can be reliably determined, and the reliability of defect detection is improved.

In addition, the presence or absence of a defect can be reliably determined as described above, and the laser beam is scanned in the plane direction of the opening end face of the hollow fiber membrane.
The scattered light generated by the light colliding with the inert particles
By detecting with a camera, the position of a defective portion can also be detected.

[Brief description of the drawings]

FIG. 1 is a simplified longitudinal sectional view of a hollow fiber membrane module showing a method for detecting a defect in a hollow fiber membrane module according to one embodiment of the present invention.

FIG. 2A is a schematic configuration diagram of a defect position detection apparatus to which a defect detection method for a hollow fiber membrane module according to one embodiment of the present invention is applied, and FIG. FIG. 3 is a schematic diagram illustrating a camera image in which a defect position is detected by the camera of FIG.

FIG. 3 is a simplified perspective view of a hollow fiber membrane module showing a conventional method for detecting a defect in a hollow fiber membrane module.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hollow fiber membrane module 2 Hollow fiber membrane 3 Hollow fiber membrane bundle 4 Case 5 Sealing material 6 Hollow fiber membrane opening end face 7 Laser beam 8 Laser part 9 Lens 10 Image intensifier 11 Camera

Continuation of the front page (56) References JP-A-3-127614 (JP, A) JP-A-59-198336 (JP, A) JP-A-4-77646 (JP, A) JP-A-5-184886 (JP) , A) JP-A-5-332892 (JP, A) JP-A-53-134776 (JP, A) JP-A-61-220710 (JP, A) JP-A-6-1233693 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B01D 65/10

Claims (1)

(57) [Claims] 1. A method according to claim 1, wherein a plurality of hollow fiber membranes inserted into the case are opened with the ends of the hollow fiber membranes being opened at the end of the case opening. A method for inspecting a defect of a hollow fiber membrane module in which a gap between cases is sealed and fixed with a sealing material, wherein a gas in which fine particles of a predetermined size are dispersed at a certain concentration is passed through the hollow fiber membrane module, The laser beam is scanned in the plane direction of the open end face of the hollow fiber membrane, and the inert particles passing through the hollow fiber membrane module are applied to the laser beam.
Scattered light due to laser light collision is used as defect location information.
A method for detecting a defect in a hollow fiber membrane module, wherein the defect is detected by a camera .