JP3664083B2 - Leak test method for hollow fiber membrane module - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a leak test method for a hollow fiber membrane module used in hemodialyzers, blood filters, and the like.
[0002]
[Prior art]
A general structure of the hollow fiber membrane module is shown in a sectional view in FIG. The hollow fiber membrane module 1 is configured by disposing a hollow fiber membrane 2 having fine pores in a housing, which has been subjected to a hydrophilic treatment on a hydrophobic substrate. Although only one hollow fiber membrane 2 is shown in FIG. 3 for the sake of clarity of illustration, a large number of hollow fiber membranes 2 are actually used. The housing includes an outer cylinder 3 and end covers 4a and 4b. Partition walls 5 a and 5 b are installed at both ends of the outer cylinder 3, and both ends of the hollow fiber membrane 2 are fixed. The space in the housing is isolated by the hollow fiber membrane 2 and is divided into a first compartment 6 mainly composed of a lumen of the hollow fiber membrane 2 and a second compartment 7 outside the hollow fiber membrane 2. A first inflow port 8 a is formed in the end cover 4 a, and a first outflow port 8 b is formed in the end cover 4 b and communicates with the first compartment 6. A second inflow port 9 a and a second outflow port 9 b are formed in the outer cylinder 3 and communicate with the second section 7.
[0003]
When this hollow fiber membrane module 1 is used in a hemodialyzer, normally, blood flows into the first compartment 6, that is, the lumen of the hollow fiber membrane 2, and the second compartment 7, that is, the dialysate outside the hollow fiber membrane 2. The dialysis function is activated by flowing.
[0004]
In such a structure and use, if one of the many hollow fiber membranes 2 is damaged, blood leaks and becomes unusable. Therefore, when manufacturing the hollow fiber membrane module 1, it is essential to perform a leak test.
[0005]
As a conventional leak test method, there is a method described in JP-A-10-15059. An outline of an apparatus for carrying out this method will be described with reference to the schematic diagram of FIG. With this apparatus, a leak test of the hollow fiber membrane module 1 similar to that shown in FIG. 3 is performed.
[0006]
In FIG. 4, 20 is a liquid supply means comprising a liquid feed pump or the like, and liquid is supplied to the first inlet 8a and the second inlet 9a of the hollow fiber membrane module 1 through the closing means 21 and 22 comprising piping valves and the like. Connected to supply. Further, a pressure detecting means 24 is connected to the first inflow port 8a through a closing means 23. A differential pressure master 25 is connected to the pressure detection means 24, and a gas supply means 27 is connected via a closing means 26.
[0007]
Reference numeral 28 denotes a decompression unit comprising a vacuum pump or the like, and is connected to the first outlet 8b and the second outlet 9b via the closing units 29 and 30. The first outflow port 8b and the second outflow port 9b are respectively switched by the closing means 31 and 32 between an open state communicated with the outside and a closed state blocked from the outside. A pressure gauge 33 is installed between the decompression means 28 and the closing means 29.
[0008]
When performing a leak test using this apparatus, first, the first compartment 6 and the second compartment 7 are filled with liquid (reverse osmosis water). For this purpose, the closing means 23, 26, 29, 30 are closed, the closing means 21, 22, 31, 32 are opened, the liquid supply means 20 is activated, and the first compartment from the liquid storage tank (not shown). The liquid is fed to 6 and the second compartment 7.
[0009]
Next, a process of filling the micropores of the hollow fiber membrane 2 with a liquid (hereinafter also referred to as “liquid filling process”) is performed. For this purpose, the closing means 21, 22, 23, 26, 31, 32 are closed, the closing means 29, 30 are opened, the decompression means 28 is operated, and the first section 6 and the second section 7 are set to a predetermined pressure. Depressurize until. Thereby, the gas remaining in the micropores of the hollow fiber membrane 2 can be removed, and the micropores can be filled with liquid.
[0010]
Next, the closing means 21, 22, 29, 30, 32 are closed, the closing means 23, 26, 31 are opened, the gas supply means 27 is activated, and the liquid filled in the first compartment 6 is discharged. .
[0011]
Next, the closing means 21, 22, 29, 30, 31 are closed, the closing means 23, 26, 32 are opened, and the gas supply means 27 is operated and pressurized. When the pressure detecting means 24 detects that the predetermined pressure has been reached, the gas supply means 27 is stopped and the closing means 26 is closed.
[0012]
In this state, measurement for a leak test is performed. That is, a predetermined pressure is generated in the differential pressure master 25, and the differential pressure is obtained by comparison with the pressure in the first section 6 detected by the pressure detection means 24, and the presence or absence of a leak is determined.
[0013]
The principle of this method is as follows. That is, by the above liquid filling process, the micropores become gas-impermeable up to the pressure (bubble point) for extruding the liquid in the micropores. Therefore, the presence or absence of leak can be easily determined by giving a pressure difference equal to or less than the bubble point between the membranes of the hollow fiber membranes 2 and detecting whether or not gas passes based on the change in pressure. This method has an advantage that it is not necessary to set a critical value (for determining the presence or absence of a leak), which is necessary when simply using the permeability of gas or liquid.
[0014]
[Problems to be solved by the invention]
The conventional method has the following problems.
[0015]
First, the apparatus for performing the leak test is complicated and large. That is, in the liquid filling process, both the first compartment 6 and the second compartment 7 are filled with the liquid, and then the pressure is reduced to fill the fine holes with the liquid. Furthermore, prior to pressurization with gas for measurement, the liquid filled in the first compartment 6 must be discharged. In order to take such a process, the leak test apparatus requires a large number of pipes as shown in FIG. In addition, the number of valves used as closing means is large, and the number of parts for switching control is also large. There is also concern about the effect on the differential pressure due to the lack of airtightness of the valve itself. Furthermore, a pressure reducing means for performing the liquid filling process is required, and the strength of the piping to withstand the pressure reduction is also required. For these reasons, the apparatus must be complicated and large.
[0016]
Further, during the decompression step, not only the hollow fiber membrane 2 but also the entire hollow fiber membrane module 1 is loaded. That is, in the depressurization step, the closing means communicating with the first inlet 8a, the first outlet 8b, and the second inlet 9a of the hollow fiber membrane module 1 shown in FIG. 3 is closed and sucked from the second outlet 9b. Is done. Therefore, the hollow fiber membrane module 1 is subjected to a load due to a differential pressure from the atmospheric pressure. By the way, when a plastic product such as a dialyzer is sterilized, deterioration of the material progresses during sterilization and / or after sterilization. Therefore, it is desirable to minimize the load on the hollow fiber membrane module before the sterilization process in order to improve productivity.
[0017]
An object of this invention is to provide the leak test method of a hollow fiber membrane module which can be implemented using a simple and small apparatus. It is another object of the present invention to provide a leak test method in which a load applied to the hollow fiber membrane module during the leak test is reduced.
[0018]
[Means for Solving the Problems]
A hollow fiber membrane module to be tested by the leak test method and the leak test apparatus of the present invention includes a hollow fiber membrane having a fine pore, a hydrophobic base material subjected to a hydrophilic treatment, and a housing containing a large number of the hollow fiber membranes. And a pair of partition walls for fixing both ends of the hollow fiber membrane in the housing. The hollow fiber membrane and the pair of partition walls are separated to form a first compartment in the hollow of the hollow fiber membrane and a second compartment outside the hollow fiber membrane, and the housing communicates with the first compartment. A first inlet and a first outlet are formed, and a second inlet and a second outlet communicated with the second section are formed.
[0019]
In the leak test method of the present invention, the first inflow port is closed , the first outflow port is allowed to flow out, the second outflow port is closed, and the second inflow port is connected to the second inflow port. By supplying liquid to the compartment and performing suction from the first outlet, and allowing the liquid in the second compartment to pass through the hollow fiber membrane toward the first compartment, the micropores in the hollow fiber membrane while a step of filling the liquid, the first inlet is closed, thereby connecting the first outlet to the measurement system, which is open at least one of said second inlet and said second outlet port to, And a step of stopping the pressurization after introducing a gas from the measurement system into the first compartment to pressurize to a predetermined pressure, and a step of measuring a subsequent change in pressure.
[0020]
According to this method, the filling of the liquid into the micropores of the hollow fiber membrane is performed by supplying the liquid from the second inflow port to the second compartment and simultaneously performing suction from the first outflow port. This can be done by permeating the hollow fiber membrane toward the first compartment . Accordingly, the piping of the test apparatus for filling the liquid into the module is small, the switching control is simple, and the apparatus is simple and small. In the liquid filling process, only it takes transmembrane pressure in the hollow fiber membranes, can reduce the load applied to the housing.
[0021]
In the above method, preferably, before the step of filling the micropores of the hollow fiber membrane with liquid, the second outlet is opened and liquid is supplied to the second compartment by supplying liquid from the second inlet. Filling. By filling the liquid in the second compartment in advance and removing the gas in the second compartment, it is possible to prevent bubbles from being mixed into the micropores when the micropores of the hollow fiber membrane are filled with the liquid. Because. In particular, including this step in a leak test of a hollow fiber membrane having a relatively low gas permeability is effective because it can smoothly fill the micropores with liquid.
[0023]
The leak test apparatus according to the present invention includes a means for closing the first inlet, a switching valve to which the first outlet is connected, and a drain connected to one of the flow paths selected by the switching valve. System, a measurement system connected to another one of the flow paths selected by the switching valve, a liquid supply valve connected to the second inlet, and a liquid supply device connected to the liquid supply valve And a drain valve connected to the second outlet. The measurement system includes an air supply device capable of supplying gas to the first compartment and pressurizing to a predetermined pressure, and a pressure gauge for measuring the pressure in the first compartment or a change in pressure.
[0024]
According to this configuration, it is possible to realize a simple and small apparatus that can appropriately perform the leak test method.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematic diagram showing a test apparatus for carrying out a leak test method for a hollow fiber membrane module according to an embodiment of the present invention. FIG. 2 is a cross-sectional view for explaining the operation in the hollow fiber membrane module 1 when a leak test is performed with the apparatus of FIG. 1 and 2, for the hollow fiber membrane module 1, the same elements as those in FIG.
[0026]
As shown in FIG. 1, during the leak test, the first inlet 8a is always closed. The first outlet 8 b is selectively connected to the leak tester 12 and the vacuum drainage system 13 via the three-way valve 11. The leak tester 12 is connected to the first compartment 6 by switching the three-way valve 11 and is a device for measuring the pressure in the first compartment 6 or a pressure change. Further, an air supply device 14 is connected so that air can be supplied via the leak tester 12. The second inlet 9 a is connected to the liquid supply device 16 via the liquid supply valve 15, and the second outlet 9 b is connected to the exhaust valve 17.
[0027]
A method for performing a leak test using this apparatus will be described below for each process.
[0028]
(Filling liquid into the module)
The liquid supply valve 15 and the drain valve 17 are opened, and the three-way valve 11 is closed. In this state, a liquid (purified water such as reverse osmosis water) is supplied from the liquid supply device 16, and the second compartment 7 is filled with the liquid as shown in FIG.
[0029]
Note that the above-described process of filling the liquid into the module may be omitted. That is, you may make it perform the filling of the water to the 2nd division 7 with the liquid filling process described below.
[0030]
(Filling the hollow fiber with fine liquid)
The three-way valve 11 is switched from the leak tester 12 side to the vacuum drainage liquid system 13 side. In this state, the liquid is supplied from the liquid supply device 16, and the liquid is filtered through the hollow fiber membrane 2 by the supply pressure of the liquid and suction from the vacuum drainage system 13, as shown in FIG. Do. As a result, the fine holes of the hollow fiber membrane 2 are filled with the liquid. The filtered liquid is drained by the vacuum drainage system 13 through the first compartment 6 .
[0031]
(Leak test)
The liquid supply valve 15 is closed and the drainage valve 17 is opened. The three-way valve 11 is switched from the vacuum drainage system 13 side to the leak tester 12 side. In this state, air is introduced into the first section 6 by the air supply device 14 and pressurized to a predetermined pressure. The pressure must be set below the bubble point. As a preferable example, the transmembrane pressure difference in the hollow fiber membrane 2 is set to 66.7 kPa.
[0032]
With the first section 6 at a predetermined pressure, pressurization by the air supply device 14 is stopped, and the subsequent pressure change is measured by the leak tester 12.
[0033]
As shown in FIG.2 (c), since it is in the state which can drain from the drainage valve 17, ie, the 2nd outflow port 9b, if there is a broken part in the hollow fiber membrane 2, it will be in the 1st division 6 The introduced air leaks through the hollow fiber membrane 2. If there is a leak, the air pressure in the first section 7 is lowered, so that a pressure drop is observed by the leak tester 12, and a leak due to the breakage of the hollow fiber membrane 2 can be detected.
[0034]
In the above test method, the method of allowing the liquid in the second compartment 7 to pass through the membrane toward the first compartment is adopted in the liquid filling process, so that the liquid can be easily filled into the module, and the leak test is performed. No previous drain is required. Accordingly, the number of piping of the test apparatus is small, the switching control is simple, and the apparatus is simple and small.
[0035]
Further, in the liquid filling process, as is apparent from FIG. 2 (c), only the transmembrane pressure is applied to the hollow fiber membrane 2, and a load is applied to the housing composed of the outer cylinder 3 and the end covers 4a and 4b. It does not take. Therefore, deterioration of the housing material at the time of manufacture is reduced.
[0036]
【The invention's effect】
According to the present invention, the filling of the liquid into the micropores of the hollow fiber membrane is performed by supplying the liquid from the second inlet to the second compartment and simultaneously performing the suction from the first outlet, This can be done by permeating the hollow fiber membrane toward the first compartment. Accordingly, the piping of the test apparatus for filling the liquid into the module is small, the switching control is simple, and the apparatus is simple and small. Further, in the liquid filling process, only the transmembrane pressure difference is applied to the hollow fiber membrane, and the load applied to the hollow fiber membrane module during the leak test is reduced.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing an apparatus for carrying out a leak test method for a hollow fiber membrane module according to an embodiment of the present invention. FIG. 2 explains the operation of the main part of FIG. 1 when a leak test is performed. FIG. 3 is a cross-sectional view showing an outline of the structure of a hollow fiber membrane module. FIG. 4 is a schematic view showing an apparatus for performing a leak test method for a hollow fiber membrane module of a conventional example. ]
DESCRIPTION OF SYMBOLS 1 Hollow fiber membrane module 2 Hollow fiber membrane 3 Outer cylinder 4a, 4b End cover 5a, 5b Partition 6 1st division 7 2nd division 8a 1st inflow port 8b 1st outflow port 9a 2nd inflow port 9b 2nd outflow port 11 Three-way valve 12 Leak tester 13 Vacuum drainage system 14 Air supply device 15 Liquid supply valve 16 Liquid supply device 17 Drainage valve 20 Liquid supply means 21, 22, 23, 26, 29, 30, 31, 32 Closure means 24 Pressure detection means 25 Differential pressure master 27 Gas supply means 28 Pressure reduction means 33 Pressure gauge

Claims (3)

A hollow fiber membrane having a microporous, hydrophilized hydrophilic substrate, a housing containing a large number of the hollow fiber membranes, and a pair of both ends of the hollow fiber membrane fixed in the housing. A first partition of a lumen of the hollow fiber membrane and a second partition outside of the hollow fiber membrane are formed by being separated by the hollow fiber membrane and a pair of partition walls, A first inlet and a first outlet communicating with the first compartment, and a second inlet and a second outlet communicating with the second compartment are formed, and blood is supplied to the first compartment during use. A leak test method for a hollow fiber membrane module in which the dialysate is flowed to the second compartment ,
Closing the first inlet, the first outlet and the ready discharge of the liquid, closes the second outlet, wherein while liquid supply to said second compartment from said second inlet the Filling the fine holes of the hollow fiber membrane with liquid by performing suction from one outlet and allowing the liquid in the second compartment to pass through the hollow fiber membrane toward the first compartment;
The first inlet is closed, the first outlet is connected to the measurement system, and at least one of the second inlet or the second outlet is opened, the first compartment is removed from the measurement system. A step of stopping the pressurization after introducing a gas to pressurize to a predetermined pressure;
And a step of measuring a subsequent change in pressure. A leak test method for a hollow fiber membrane module.   Including the step of filling the second compartment with the liquid by opening the second outlet and supplying the liquid from the second inlet before the step of filling the hollow holes of the hollow fiber membrane with the liquid. The leak test method for a hollow fiber membrane module according to claim 1. A leak test apparatus used for carrying out the leak test method for a hollow fiber membrane module according to claim 1 or 2,
Means for closing the first inlet;
A switching valve to which the first outlet is connected;
A drainage system connected to one of the flow paths selected by the switching valve;
A measurement system connected to another one of the flow paths selected by the switching valve;
A liquid supply valve connected to the second inlet;
A liquid supply device connected to the liquid supply valve;
A drainage valve connected to the second outlet,
The measurement system includes an air supply device capable of supplying gas to the first compartment and pressurizing to a predetermined pressure, and a pressure gauge for measuring the pressure of the first compartment or a change in pressure. Leak test device for hollow fiber membrane module.

Images