JP5729683B2 - Integrity test method and test equipment for porous hollow fiber membrane module - Google Patents

Description

  The present invention relates to an integrity test method and test apparatus for a porous hollow fiber membrane module, and more particularly, to perform accurately and automatically simultaneously on a plurality of porous hollow fiber membrane modules in a shallow bathtub. The present invention relates to an integrity test method and a test apparatus for a porous hollow fiber membrane module capable of performing the above.

  There is a pressure holding test as a test method for directly evaluating the integrity of the porous hollow fiber membrane module. As a general method of this pressure holding test, the porous hollow fiber membrane module is immersed in water for a predetermined time to sufficiently wet the surface pores of the porous hollow fiber membrane, and then the primary hollow porous fiber membrane in water. A method is known in which pressurized air is fed to the side or the secondary side, and then sealed, and after a predetermined time has passed, the pressure is measured to evaluate the integrity (pass / fail judgment) of the porous hollow fiber membrane module. .

  This method is simple but has high measurement accuracy, and is widely used as a method for evaluating the integrity of a porous hollow fiber membrane module.

JP 2007-244500 A JP 2004-212230 A

  However, since the inspection of the above-mentioned patent document is performed with the porous hollow fiber membrane module standing upright, the inspection bath needs to have a depth greater than the length of the porous hollow fiber membrane module. For this reason, when it is going to apply the inspection method of the above-mentioned patent document to the inspection in the manufacturing process of the porous hollow fiber membrane module whose module length exceeds 1 m, the workability and safety of the inspection are improved depending on the depth of the bathtub. Clearly it is difficult to secure.

In addition, in the pressure holding test, if the position in the bathtub (that is, the water depth of the arrangement location) is different, the working water pressure is different, so even if the same internal pressure is applied to the same porous hollow fiber membrane module, the arrangement is The internal pressure value (holding pressure value) after the elapse of a predetermined time varies depending on the water depth of the place.
For this reason, in a pressure holding test in which a flat porous hollow fiber membrane module is stacked horizontally in a bathtub, the effect of water pressure must be taken into account, and the test result must be evaluated (pass / fail judgment) There was a problem that was complicated.

  Furthermore, in the pressure holding test, when there are a plurality of porous hollow fiber membrane modules to be inspected, there is a difference in integrity for each porous hollow fiber membrane module to be inspected. It comes in a slightly shifted state. The operation of manually reading and recording the pressure gauge value has to be performed continuously in about a few seconds, which is very difficult.

  The present invention has been made to solve the above-described problem, and the pressure holding test in the porous hollow fiber membrane module manufacturing process can be simultaneously performed on a plurality of porous hollow fiber membrane modules in a shallow bathtub. An object of the present invention is to provide an integrity test method and test apparatus for a porous hollow fiber membrane module.

According to the present invention,
A method for testing the integrity of a porous hollow fiber membrane module,
Dipping a plurality of porous hollow fiber membrane modules side by side in a vertical direction so as to extend horizontally in a liquid filled in a bathtub;
A step of connecting a pressure pump to each porous hollow fiber membrane module and pressurizing the inside of the hollow fiber membrane constituting each porous hollow fiber membrane module;
Stopping the pressurization and sealing each porous hollow fiber membrane module;
Measuring the pressure drop in the sealed space in each porous hollow fiber membrane module;
Based on the measurement result, performing a pass / fail judgment of the porous hollow fiber membrane module in which the depth position in the bathtub of the porous hollow fiber membrane module is corrected, and
Equipped with a,
A calibration curve showing the relationship between the holding pressure and the water depth is created from data obtained by measuring the holding pressure at a plurality of water depths using a porous hollow fiber membrane module having acceptable performance, and the depth is calculated based on the calibration curve. A method for testing the integrity of a porous hollow fiber membrane module is provided, wherein the position correction is performed .

According to such a configuration, a pressure holding test of a plurality of membrane modules can be performed while ensuring workability and safety, and the influence of water pressure can be corrected appropriately.
By performing pressure holding tests on multiple membrane modules at the same time, the inspection efficiency is greatly improved, and further, the work load on humans can be greatly reduced by using a device that can automatically perform this series of pressure holding tests. .
Furthermore, according to the present invention,
A method for testing the integrity of a porous hollow fiber membrane module,
Dipping a plurality of porous hollow fiber membrane modules side by side in a vertical direction so as to extend horizontally in a liquid filled in a bathtub;
A step of connecting a pressure pump to each porous hollow fiber membrane module and pressurizing the inside of the hollow fiber membrane constituting each porous hollow fiber membrane module;
Stopping the pressurization and sealing each porous hollow fiber membrane module;
Measuring the pressure drop in the sealed space in each porous hollow fiber membrane module;
Based on the measurement result, performing a pass / fail judgment of the porous hollow fiber membrane module in which the depth position in the bathtub of the porous hollow fiber membrane module is corrected, and
With
Using a hollow hollow fiber membrane module with acceptable performance, create a descending curve that shows the relationship between transmembrane pressure and time, and identify the curve by translating it until it crosses a specific initial transmembrane pressure value. An inter-membrane differential pressure value of a hollow fiber membrane module having a pass threshold value at a water depth is determined, and the depth position is corrected based on the result, and the integrity test of the porous hollow fiber membrane module A method is provided.

According to another preferred embodiment of the invention,
The liquid in the bath is water or an aqueous solution of a surfactant.

According to another preferred embodiment of the invention,
The plurality of adjacent porous hollow fiber membrane modules adjacent to each other are spaced apart by a distance larger than the thickness of the porous hollow fiber membrane module.
According to another preferred embodiment of the invention,
An interval between adjacent porous hollow fiber membrane modules is set to 40 mm to 100 mm.

According to another preferred aspect of the present invention, the depth position is corrected by making the initial transmembrane pressure difference the same.

According to another preferred embodiment of the invention,
The depth position is corrected by adjusting the transmembrane pressure difference with a regulator provided for each module.

According to another aspect of the present invention, there is provided a test apparatus for carrying out the above integrity test method,
A porous hollow fiber membrane module to be tested and a bathtub containing a liquid in which the porous hollow fiber membrane module is immersed;
A pressure pump;
An air pipe communicating between the pressurizing pump and the hollow fiber membrane constituting the hollow fiber membrane module;
A pressure gauge for measuring the pressure inside hollow fiber membrane inside is provided in the air pipe,
An electromagnetic valve provided in the air pipe for selectively opening and closing the air pipe ;
A control device connected to the pressure gauge and the solenoid valve,
A test apparatus is provided.

According to another preferred embodiment of the invention,
The control device is
A process of opening the electromagnetic valve and starting the test;
A process of closing the solenoid valve when the output value of the pressure gauge reaches a predetermined value;
A process of continuously recording the output value of the pressure gauge over a predetermined time;
After the predetermined time has elapsed, a process of comparing the recording result with predetermined reference data and determining the integrity of the porous hollow fiber membrane module is executed.

According to another preferred embodiment of the invention,
An interval adjusting means is provided between the adjacent porous hollow fiber membrane modules.

According to another preferred embodiment of the invention,
A regulator corresponding to each hollow fiber membrane module is provided on the upstream side of the electromagnetic valve of the air conduit.

  Unit having such a configuration According to the present invention, a porous hollow fiber capable of simultaneously performing a pressure holding test in a porous hollow fiber membrane module manufacturing process on a plurality of porous hollow fiber membrane modules in a shallow bathtub. A membrane module integrity test method and test apparatus are provided.

It is drawing which shows schematic structure of the testing apparatus which implements the integrity test method of the porous hollow fiber membrane module of preferable embodiment of this invention. (A), (b) is drawing explaining the attachment method in the case of testing a cylindrical porous hollow fiber membrane module. It is a flowchart explaining the integrity test method of the porous hollow fiber membrane module of preferable embodiment of this invention performed using the test apparatus of FIG. It is the graph and table | surface which show the relationship between the holding pressure after the specific time progress of a porous hollow fiber membrane module, and the water depth in the pressure holding test of a flat type porous hollow fiber membrane module. It is a graph and table | surface which show the fall of transmembrane differential pressure. It is a graph which shows the fall of transmembrane differential pressure. It is a graph which shows deriving an acceptance pressure maintenance standard by adding water pressure to an acceptance transmembrane differential pressure standard. It is drawing which shows schematic structure of the other test apparatus which enforces the integrity test method of the porous hollow fiber membrane module of preferable embodiment of this invention. It is drawing explaining the preparation method of the calibration curve in the Example of this invention.

  Below, with reference to an accompanying drawing, the integrity test method of the porous hollow fiber membrane module of preferable embodiment of this invention is demonstrated in detail.

  FIG. 1 is a drawing showing a schematic configuration of a test apparatus for carrying out an integrity test method for a porous hollow fiber membrane module according to a preferred embodiment of the present invention.

  As shown in FIG. 1, the test apparatus 1 includes a bathtub 4 that accommodates inspection water 2. In the present embodiment, a surfactant aqueous solution obtained by adding a surfactant or the like to tap water is used as the inspection water 2, and the depth of the bathtub 4 is not particularly limited. In consideration of about 0.4 to 0.5 m.

  As shown in FIG. 1, in the test apparatus 1, the bathtub 4 has five porous hollow fiber membrane modules 6 to be tested arranged side by side in a vertically extending state (horizontal placement). It is configured to be able to. One end of each porous hollow fiber membrane module 6 is connected to a pipe line 10 communicating with the pressure pump 8 so that pressurized air can be sent into the porous hollow fiber membrane module 6. This pipe line 10 is provided with an electromagnetic valve 12 and a pressure gauge 14 for each porous hollow fiber membrane module 6, and pressurized air is turned on and off for each porous hollow fiber membrane module 6 by a control device such as a computer 16. Control and internal pressure measurement are possible.

  In this embodiment, a conduit 10 communicating with the pressurizing pump 8 is connected to the water discharge side of the porous hollow fiber membrane module 6. In addition, you may connect the pipe line 10 to the water absorption side.

  The shape of the porous hollow fiber membrane module 6 to be inspected is preferably a flat type in that it can be arranged compactly, but is not limited to the flat type as long as it can be placed horizontally and regularly arranged in the vertical direction.

  For example, even in the case of a cylindrical porous hollow fiber membrane module 18, a regular arrangement state using jigs 20, 20 fitted at both ends of the porous hollow fiber membrane module 18 as shown in FIG. (FIG. 2B) can be set as an inspection object.

  In the present embodiment, for example, the thickness of the flat porous hollow fiber membrane module 6 to be inspected is about 10 to 30 mm, and the outside of the porous hollow fiber membrane constituting the porous membrane hollow fiber membrane module 6 is The diameter (that is, the thickness of the hollow fiber membrane bundle) is about 1.5 mm to 5 mm.

  The material of the membrane of the porous hollow fiber membrane module 18 is preferably a polymer organic membrane such as polyethylene, polysulfone, and polyvinylidene fluoride.

  The number of the porous hollow fiber membrane modules that are arranged side by side in the vertical direction is not particularly limited. However, in consideration of workability, the number of arrangement is 5 to 10 in the bathtub 4. The depth of the inspection water is preferably 0.5 m or less.

  As the surfactant used in the present embodiment, an anionic surfactant, a cationic surfactant, an amphoteric surfactant and a nonionic surfactant can be selected, but from the viewpoint of less foaming / bubbles, Nonionic surfactants are particularly preferred.

  Specific examples of nonionic surfactants include acetylene glycol surfactants, acetylene alcohol surfactants, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene dodecylphenyl ether, polyoxyethylene alkylallyl. Ethers such as ether, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene alkyl ether, polyoxyalkylene alkyl ether, polyoxyethylene oleic acid, polyoxyethylene oleic acid ester, polyoxyethylene distearic acid ester, Sorbitan laurate, sorbitan monostearate, sorbitan monooleate, sorbitan sesquioleate, polyoxyethylene Monooleate, polyoxyethylene stearate, etc. esters, silicone surface active agents dimethylpolysiloxane, other fluorine alkyl esters, fluorine-containing surfactants such as perfluoroalkyl carboxylic acid salts, and the like.

  Among nonionic surfactants, acetylene glycol surfactants are particularly preferable because they have excellent wettability, permeability, and antifoaming property. Furthermore, the acetylene glycol surfactant is a relatively stable substance and has a characteristic that it is not subject to decay by organisms even during long-term film storage. The acetylene glycol-based surfactant has characteristics such as high permeability such as low dynamic surface tension. Therefore, it can be suitably used for hydrophilic treatment of a hollow fiber membrane having a relatively large thickness, and has effects such as shortening the treatment time.

  Specific examples of the acetylene alcohol surfactant include 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, , 5-dimethyl-1-hexyne-3ol, 2,5,8,11-tetramethyl-6-dodecyne-5,8-diol, ethoxylated compounds thereof, and the like.

  These can be used by appropriately selecting one or more kinds as necessary, and among them, the ethoxylated product preferably has a total ethylene oxide addition mole number in the range of 2 to 30 moles. More preferably, it is the range of 4-12 mol. It is preferable that the total number of moles of ethylene oxide added is 30 moles or less because static and dynamic surface tensions are lowered and can be used as a hydrophilizing agent.

  The acetylene glycol surfactant and its ethoxylated product are also commercially available. For example, Surfynol 104, 82, 465, 485 manufactured by Air Products, TG or Olphine STG manufactured by Nisshin Chemical Co., Ltd. E1010, Olphine EXP4036, Olphine PD-001 and the like.

  For example, one kind of acetylene glycol surfactant, orphine EXP4036 (manufactured by Nissin Chemical Industry Co., Ltd.), exhibits a static surface tension of 30 mN / m or less at 0.1 wt%. Orphin PD-001 / Olfin STG (both manufactured by Nissin Chemical Industry Co., Ltd.) similarly exhibits a static surface tension of 30 mN / m or less at 0.1 wt%. As described above, the acetylene glycol-based surfactant can exhibit good hydrophilicity at an extremely low concentration.

  In this embodiment, tap water was used as a solvent for dissolving the surfactant. In addition to this, pure water, an aqueous solution containing an electrolyte such as physiological saline, ethanol, methanol, etc., 1 to 4 carbon atoms, preferably May be a lower alcohol having 1 to 2 carbon atoms, pyridine, chloroform, cyclohexane, ethyl acetate, toluene, or a mixed solvent thereof.

  In particular, it is more preferable to use water from the viewpoints of the influence on the material to be subjected to the hydrophilization treatment, the post-treatment of the solvent, safety, or cost. In particular, water obtained by filtering ion-exchanged water with a hollow fiber membrane having a pore diameter of 0.01 to 1 μm in addition to normal tap water is preferable.

  The surfactant is prepared by dissolving in an aqueous solvent alone or together with the active agent and optional additives.

  Examples of the method for dissolving the surfactant in the solvent include a method of mixing by a known mixing preparation method such as a propeller type stirrer. In addition, components that are solid at room temperature can be heated and mixed as necessary.

  The hydrophobic porous membrane hydrophilizing agent used in the present embodiment is 0.05 to 5% by mass, preferably 0.05 to 1% of the surfactant based on the entire hydrophobic porous membrane hydrophilizing agent. It is preferable to contain in the range of mass%. By setting the surfactant to 0.05% by mass or more, excellent properties as a hydrophilizing agent tend to be imparted. In addition, by setting the surfactant to 5% by mass or less, the amount of elution from the membrane decreases, and COD tends to be reduced.

  The influence of the water temperature on the surface tension of the test water is negligible because it is negligible at room temperature. However, it is preferable to keep the temperature between 18 ° C. and 25 ° C. in consideration of workability.

  The surface tension and the surfactant concentration are not particularly limited, but if the surface tension is too high, the air pressure held in the membrane module is difficult to decrease, so the test water has an interface where the surface tension is 30 mN / m or less. The activator concentration is preferred.

  Next, the integrity test method for the porous hollow fiber membrane module according to the preferred embodiment of the present invention, which is performed using the test apparatus 1, will be described with reference to the flowchart of FIG. 3.

  First, as shown in FIG. 1, the porous hollow fiber membrane module 6 is immersed in the inspection water 2 in the bathtub 4 and the inspection is started (step S1). The solenoid valve 12 is opened (step S2), and the pressurized air from the pressurizing pump 8 passes through the conduit 10 into the porous hollow fiber membrane module 6, specifically, the water collecting channel of the porous hollow fiber membrane module. And fed into the hollow part of the porous hollow fiber membrane.

  If it is determined in step S3 that the inside of the porous hollow fiber membrane module 6 has reached a predetermined set pressure, the process proceeds to step S4, the electromagnetic valve 12 is closed, and the internal pressure in each porous hollow fiber membrane module 6 is increased. While the pressure is stopped, the inside of each porous hollow fiber membrane module 6 is sealed, and the pressure gauge 14 starts measuring the pressure in each porous hollow fiber membrane module 6 and measuring the pressure holding time.

  If it is determined in step S5 that a predetermined pressure holding time of, for example, 2.5 minutes or more has elapsed, the process proceeds to step S6. In step S6, the measurement of the pressure in each porous hollow fiber membrane module 6 and the measurement of the pressure holding time are finished, and each porous hollow fiber membrane module 6 is measured based on the measured pressure value in each porous hollow fiber membrane module 6. The integrity of the yarn membrane module 6 is determined (pass / fail determination). That is, the measured value is compared with predetermined reference data to determine whether or not each porous hollow fiber membrane module 6 has predetermined integrity (predetermined performance), and in step S7, The result of the pass / fail determination is output and stored together with the holding pressure value (step S7), and the process ends.

  Next, determination of the test result (pass / fail determination) of each porous hollow fiber membrane module 6 performed in step S6 will be described.

In the pressure holding test of the porous hollow fiber membrane module, it was found that the holding pressure of the membrane module after a specific time elapsed was substantially proportional to the water depth, as shown in FIG.
In the pass / fail judgment in step S6 of the present embodiment, a calibration curve showing the relationship between the holding pressure and the water depth using the porous hollow fiber membrane module having the performance that passes the normal pressure holding test using the proportional relationship. And using this calibration curve, a pass criterion is set for each water depth, and this set value is used as a threshold value, and a pass / fail judgment is made by comparing with the pressure after the pressure holding time has elapsed.

  As another method for correcting the influence of the holding pressure due to the water pressure, a method of determining an acceptance criterion according to the water depth in consideration of the transmembrane pressure difference may be adopted. It was found that the transmembrane pressure difference draws the same descent curve regardless of the water depth if the transmembrane pressure difference value is the same in the same module (FIGS. 5 and 6).

  A curve indicating the relationship between the transmembrane pressure difference (that is, holding pressure-water pressure) and the time at a specific water depth of a porous hollow fiber membrane module having acceptable performance is created. Then, this curve is translated on the horizontal axis until it intersects with the initial transmembrane pressure value at the start of the pressure holding test at a certain water depth, and the transmembrane differential pressure value after the lapse of a predetermined time of this newly created curve is Passing film differential pressure reference at the water depth (threshold value at the specific water depth), which is corrected according to the water pressure at the measurement position, and used as a pass pressure holding reference at the measurement position (Fig. 7) Also good.

  Furthermore, another embodiment using the same descent curve regardless of the water depth can be configured if the same module and the transmembrane pressure difference are the same.

  Since each porous hollow fiber membrane module arranged horizontally is different in the arranged water depth, the working water pressure is different. For this reason, a regulator is connected to each porous membrane hollow fiber membrane module, and the primary pressure applied to the porous hollow fiber membrane module (pressure of pressurized air) is adjusted for each porous membrane hollow fiber membrane module. You may use the structure which makes transmembrane differential pressure equal in a porous membrane hollow fiber membrane module.

  As the regulator to be used, any air regulator may be used as long as it is arranged on the air pipe and used. One example is the “pilot regulator AR series” manufactured by SMC Corporation.

  By correcting the initial primary pressure according to the depth of the porous hollow fiber membrane module in this way, no special preparation such as creating a calibration curve is required, and a plurality of flat membrane modules can be simultaneously applied. A pressure holding test can be performed to determine pass / fail.

  According to the present embodiment, if the porous hollow fiber membrane module 6 is immersed in the inspection water 2 and connected to the air pipe, the pressure holding test and the pass / fail judgment can be automatically performed thereafter.

  The present invention is not limited to the embodiments and specific examples described in the present specification, and various changes and modifications can be made within the scope of the technical idea described in the claims. .

In the above embodiment, the porous membrane hollow fiber membrane modules 6 are directly stacked and arranged vertically.
However, as in the configuration shown in FIG. 8, a block B that functions as an interval adjusting mechanism is arranged between adjacent porous membrane hollow fiber membrane modules 6, and the adjacent porous membrane hollow fiber membrane modules are located between them. A space may be provided at a distance from each other.
In this example, the size of the block B is set so that the distance between the membrane surfaces of adjacent porous membrane hollow fiber membrane modules 6 is 40 mm to 100 mm, more preferably 50 mm to 75 mm.

  According to such a configuration, it is possible to easily provide a sufficient interval between adjacent porous membrane hollow fiber membrane modules, to quickly remove bubbles mixed in the hollow fiber membrane, and to promptly pass the test liquid between the hollow fiber membranes. Supply is possible.

  As the space adjusting means, any device can be used as long as it can widen the space between the adjacent porous membrane hollow fiber membrane modules. In addition to the block B in the above example, a jack or a predetermined one can be used. A plate or the like adjusted to the thickness is used.

  The test water is stirred for about 5 minutes in a stirring tank using 600 g of Orphine EXP4036 (composition: acetylenediol ethylene oxide adduct, nonionic surfactant, propylene glycol, water, etc.) with respect to 200 L of tap water. A 3% by weight aqueous surfactant solution was prepared.

  The porous hollow fiber membrane module having an acceptance threshold was immersed in inspection water for 10 minutes for the purpose of sufficiently wetting, and left standing.

  Using the same housing 20 as that used for the porous hollow fiber membrane module as a dummy, the position of the porous hollow fiber membrane module 6 in the depth direction is sequentially changed, and a specific air pressure is applied to the porous hollow fiber membrane. The module was held and subjected to a pressure holding test for 2.5 minutes (FIG. 9).

  The same operation was performed with a porous hollow fiber membrane module having acceptable performance to obtain a calibration curve.

  Five flat porous hollow fiber membrane modules are stacked on the test water adjusted in the same manner, and four 5 kg weights 22 are placed on the housing part of the porous hollow fiber membrane module (the weight is a module disposed). Up to 5 layers of flat porous hollow fiber membrane modules up to the bottom of the bath (tub height: 40 cm, water depth when 5 porous hollow fiber membrane modules are contained: 31 cm) I was completely sunk.

  The previously obtained calibration curve was stored in the control device, and pressurization, pressure holding test, and pass / fail judgment were performed by the control device. As a result, the same pass / fail judgment as in the normal pressure holding test could be obtained.

  A pressure holding test of the porous hollow fiber membrane module was performed by changing the water depth in the same manner as in Example 1, and a drop curve of the transmembrane pressure difference with time was obtained. When this curve was moved parallel to the horizontal axis and superimposed, it was confirmed that the same descent curve was drawn regardless of the water depth if the same membrane module and the same transmembrane pressure difference were used (FIG. 6).

  Porous hollow fiber membrane module with acceptable performance, generates a transmembrane differential pressure drop curve at an arbitrary water depth and parallels it to the same value as the initial transmembrane pressure value at the start of a pressure holding test at a certain water depth It was moved and the acceptance standard in specific water depth was calculated | required from the newly made curve (FIG. 7).

  Thereafter, using this acceptance criterion, as in Example 1, pressurization, pressure holding test, and pass / fail judgment were performed by the control device. As a result, the same pass / fail judgment as in the normal pressure holding test could be obtained.

  Except that all the transmembrane differential pressures at the start of measurement of the arranged membrane modules were set to the same, pressurization, pressure holding test, and pass / fail judgment were performed by the control device in the same manner as in Examples 1 and 2. Results The transmembrane pressure difference of all the membrane modules was almost the same as the value obtained in the normal pressure holding test.

[Comparative Example 1]
The time required for conducting the integrity test on the five membrane modules in the above example was about 20 min (including the porous membrane wetting time 10 min and the membrane module transport time 7 min).
On the other hand, the time required to perform the integrity test on the five membrane modules by the conventional method was about 40 min (the porous membrane was wetted for 10 min (here, 5 can be performed simultaneously), Including transport time of membrane module 17 min).

1: Test device 2: Inspection water 4: Bath 6: Porous hollow fiber membrane module 8: Pressure pump 10: Pipe 12: Electromagnetic valve 14: Pressure gauge 16: Control device

Claims (11)

A method for testing the integrity of a porous hollow fiber membrane module,
Dipping a plurality of porous hollow fiber membrane modules side by side in a vertical direction so as to extend horizontally in a liquid filled in a bathtub;
A step of connecting a pressure pump to each porous hollow fiber membrane module and pressurizing the inside of the hollow fiber membrane constituting each porous hollow fiber membrane module;
Stopping the pressurization and sealing each porous hollow fiber membrane module;
Measuring the pressure drop in the sealed space in each porous hollow fiber membrane module;
Based on the measurement result, performing a pass / fail judgment of the porous hollow fiber membrane module in which the depth position in the bathtub of the porous hollow fiber membrane module is corrected, and
With
A calibration curve showing the relationship between the holding pressure and the water depth is created from the data obtained by measuring the holding pressure at a plurality of water depths using a porous hollow fiber membrane module having acceptable performance, and the depth is calculated based on the calibration curve. A method for testing the integrity of a porous hollow fiber membrane module, wherein the position is corrected. A method for testing the integrity of a porous hollow fiber membrane module,
Dipping a plurality of porous hollow fiber membrane modules side by side in a vertical direction so as to extend horizontally in a liquid filled in a bathtub;
A step of connecting a pressure pump to each porous hollow fiber membrane module and pressurizing the inside of the hollow fiber membrane constituting each porous hollow fiber membrane module;
Stopping the pressurization and sealing each porous hollow fiber membrane module;
Measuring the pressure drop in the sealed space in each porous hollow fiber membrane module;
Based on the measurement result, performing a pass / fail judgment of the porous hollow fiber membrane module in which the depth position in the bathtub of the porous hollow fiber membrane module is corrected, and
With
Using a hollow hollow fiber membrane module with acceptable performance, create a descending curve that shows the relationship between transmembrane pressure and time, and identify the curve by translating it until it crosses a specific initial transmembrane pressure value. An inter-membrane differential pressure value of a hollow fiber membrane module having a pass threshold value at a water depth is determined, and the depth position is corrected based on the result, and the integrity test of the porous hollow fiber membrane module Method. The liquid in the bath is water or an aqueous solution of a surfactant.
The integrity test method according to claim 1 or 2. A plurality of adjacent porous hollow fiber membrane modules that are spaced apart by a distance greater than the thickness of the porous hollow fiber membrane module;
The integrity test method according to any one of claims 1 to 3. The interval between the membranes of the adjacent porous hollow fiber membrane modules is 40 mm to 100 mm,
The integrity test method according to any one of claims 1 to 4. The depth position is corrected by making the initial transmembrane pressure difference the same,
6. The integrity test method according to any one of claims 1 to 5. The depth position is corrected by adjusting the transmembrane pressure difference with a regulator provided for each module.
The integrity test method according to any one of claims 1 to 6. A test apparatus for carrying out the integrity test method according to any one of claims 1 to 7,
A porous hollow fiber membrane module to be tested and a bathtub containing a liquid in which the porous hollow fiber membrane module is immersed;
A pressure pump;
An air pipe communicating between the pressurizing pump and the hollow fiber membrane constituting the hollow fiber membrane module;
A pressure gauge for measuring the pressure inside the hollow fiber membrane provided in the air pipe;
An electromagnetic valve provided in the air pipe for selectively opening and closing the air pipe ;
A control device connected to the pressure gauge and the solenoid valve;
A test apparatus characterized by comprising: The control device is
A process of opening the electromagnetic valve and starting the test;
A process of closing the solenoid valve when the output value of the pressure gauge reaches a predetermined value;
A process of continuously recording the output value of the pressure gauge over a predetermined time;
After the predetermined time has elapsed, the recording result is compared with predetermined reference data, and a process for determining the integrity of the porous hollow fiber membrane module is performed.
The test apparatus according to claim 8. An interval adjusting means is provided between the adjacent porous hollow fiber membrane modules,
The test apparatus according to claim 8 or 9. A regulator corresponding to each hollow fiber membrane module is provided on the upstream side of the solenoid valve of the air pipe,
The test apparatus according to claim 8.

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