JP6511829B2 - Method of manufacturing hollow fiber membrane module - Google Patents

Description

  The present invention relates to a method of manufacturing a hollow fiber membrane module used in a household, industrial or medical filtration device.

Conventionally, manufacture of a hollow fiber membrane module has been performed, for example, as follows.
That is, as shown in FIG. 5, first, a bundle of hollow fiber membranes 11 or a knitted fabric is housed in a cylindrical case 12, and a potting cup 15 made of silicone or the like is attached to one end of the case 12. Then, the potting agent is injected from the center tube 16 inserted into the center of the bundle of hollow fiber membranes 11 or the woven fabric, and the potting agent is cured. Then, the potting cup 15 is removed from the case 12 and the hollow fiber membrane 11 fixed with the potting agent and the potting agent is cut along the BB 'line of the potting portion 14 to form the open end of the hollow fiber membrane 11. (See, for example, Patent Document 1).
However, this method is laborious because it is necessary to remove the potting cup 15 from the case 12 after the potting agent is cured.

Then, as a method of manufacturing a hollow fiber membrane module simply, as shown in FIG. 6, using the cylindrical case 12 which only one end opens, a potting agent is injected from the center tube 16 and the case is cured after the potting agent is cured. 12, a method of cutting along the line CC 'of the potting portion 14 has been proposed (see, for example, Patent Document 2). In this method, it is not necessary to attach and remove the potting cup, and the hollow fiber membrane module can be easily manufactured.
However, this method requires a cylindrical case 12 having only one end open. Therefore, there is a problem that a new mold for manufacturing the case 12 is required, which increases the cost. In addition, when the cylindrical case 12 is made of a material that is difficult to cut, it is difficult to manufacture a hollow fiber membrane module by this method.

Therefore, there is no need to use a special case with only one end open, and there is no need to remove the potting cup made of silicone etc after curing of the potting agent, and as a method of easily manufacturing a hollow fiber membrane module, The method of has been proposed.
That is, as shown in FIG. 7, the resin cap 13 is inserted into one end of the cylindrical case 12, the potting agent is centrifugally injected from the center tube 16, and after curing of the potting agent, the potting portion 14 is formed together with the resin cap 13. (See, for example, Patent Document 3).

Unexamined-Japanese-Patent No. 5-84426 JP-A-4-284834 JP-A-8-215546

  However, in the method shown in FIG. 7, when the potting agent is centrifugally injected, the potting agent may leak from the contact portion between the case 12 and the resin cap 13.

  The object of the present invention is that there is no need to use a special case with only one end open, there is no need to remove the potting cup made of silicone etc after curing of the potting agent, and the potting agent does not leak easily, conveniently It is an object of the present invention to provide a method by which a hollow fiber membrane module can be manufactured.

The present invention has the following aspects.
[1] A hollow fiber membrane is housed in a cylindrical case, one end of the case is sealed with a resin cap consisting of a side surface and a bottom surface, a potting agent is injected into the case and cured to form a hollow fiber membrane In a method of manufacturing a hollow fiber membrane module by fixing a case and a hollow fiber membrane module, a flange is formed on the side surface of the resin cap, and the side surface of the resin cap is sealed to the flange inside the one end of the case. After inserting the potting agent and injecting the potting agent, the resin cap, the hardened potting agent and the hollow fiber membrane fixed with the potting agent are cut at a predetermined position on the resin cap after the potting agent is cured, and the hollow fiber membrane is cut. The manufacturing method of the hollow fiber membrane module which forms the open end of a.
[2] The method for producing a hollow fiber membrane module according to [1], wherein a groove is formed inside the bottom surface of the resin cap.
[3] The method for manufacturing a hollow fiber membrane module according to [2], wherein the grooves are radially formed on the bottom surface of the resin cap.
[4] The method for producing a hollow fiber membrane module according to any one of [1] to [3], wherein an injection port for injecting a potting agent is formed on the bottom or side of the resin cap.
[5] The method for producing a hollow fiber membrane module according to [4], wherein an injection port for injecting a potting agent is formed on the bottom surface of the resin cap, and the grooves are formed radially from the potting agent injection port. .

  According to the method for producing a hollow fiber membrane module of the present invention, there is no need to use a special case having only one end open, and there is no need to remove a potting cup made of silicone etc after curing of the potting agent, The potting agent does not easily leak, and the hollow fiber membrane module can be easily manufactured.

It is sectional drawing which demonstrates an example of the hollow fiber membrane module manufacturing method of this invention typically. It is sectional drawing which shows an example of the resin-made caps used for this invention. It is the top view which looked at the resin-made cap shown in FIG. 1 from the opening part side. It is sectional drawing which shows the other example of the resin-made caps used for this invention. It is sectional drawing which demonstrates typically an example of the conventional hollow fiber membrane module manufacturing method which uses the cup for potting. It is sectional drawing which demonstrates typically an example of the conventional hollow fiber membrane module manufacturing method which does not use the cup for potting. It is sectional drawing which demonstrates typically the other example of the conventional hollow fiber membrane module manufacturing method which does not use the cup for potting.

"Method of manufacturing hollow fiber membrane module"
Hereinafter, an embodiment of a method of manufacturing a hollow fiber membrane module of the present invention will be described with reference to the drawings. The same reference numerals as in FIG. 1 denote the same constituent elements in FIGS. 2 to 7, and a description thereof will be omitted.
In the method of manufacturing a hollow fiber membrane module according to the present embodiment, as shown in FIG. 1, the hollow fiber membrane 11 is housed in a cylindrical case 12 and a resin cap comprising one end of the case 12 consisting of a side surface 13a and a bottom surface 13b. This is a method of manufacturing a hollow fiber membrane module by sealing at 13 and injecting and curing a potting agent in the case 12 to fix the hollow fiber membrane 11 and the case 12.

<Resin cap>
The resin cap 13 seals one end of the case 12 and includes a side surface 13a and a bottom surface 13b.
The material of the resin cap 13 is not particularly limited as long as it is easily cut, and examples thereof include polyethylene, polypropylene, an ABS resin, polyvinyl chloride and the like.

The resin cap 13 is inserted so as to seal the inside of one end of the case 12. Therefore, as shown in FIGS. 1 and 2, the outer diameter d ₁ of the opening 13 c of the resin cap 13 is preferably substantially the same as the inner diameter of the case 12. If the outer diameter d ₁ of the opening 13c of the resin cap 13 is substantially the same as the inner diameter of the case 12, can be inserted side 13a of the resin cap 13 on the inner side of one end of the case 12, and a resin cap 13 and the case 12 is closely fitted. In the following description, the portion of the resin cap 13 inserted into the case 12 is also referred to as the “fitting portion” of the resin cap 13.
Here, "substantially the same", or the inner diameter of the outer diameter d ₁ and the case 12 of the opening 13c of the resin cap 13 is the same, or the outer diameter d ₁ of the opening 13c of the resin cap 13 is It means that it is within ± 0.3% with respect to the inner diameter of case 12.

  Further, on the side surface 13 a of the resin cap 13, a collar 13 d is formed. The collar 13d is formed on the side surface 13a of the resin cap 13, so that the collar 13d stops when the side surface 13a of the resin cap 13 is inserted inside the one end of the case 12, and the collar 13d and one end of the case 12 are in close contact. The close fitting between the resin cap 13 and the case 12 is further enhanced by the close contact between the collar portion 13 d and one end of the case 12, and the potting agent can be prevented from leaking from the contact portion between the resin cap 13 and the case 12. .

The outer diameter d ₂ of the flange portion 13d is preferably the outer diameter of the case 12 to be substantially the same. The outer diameter d ₂ of the flange portion 13d outflow prevention effect of potting agent be greater than the outer diameter of the case 12 is leveled off, it only increases the cost.
Here, the "substantially the same" as, ± or the outer diameter of the outer diameter d ₂ and the case 12 of the flange portion 13d is the same, or the outer diameter d ₂ of the flange portion 13d is the outer diameter of the case 12 It says that it is within 2%. However, the outer diameter d ₂ of the collar 13 d is larger than the inner diameter of the case 12.

The collar 13 d is formed over the entire circumference of the resin cap 13 in the circumferential direction.
The formation position of the collar 13 d is preferably a position where the distance d ₃ from the opening 13 c of the resin cap 13 to the collar 13 d is 1 to 2 mm. The portion from the opening 13 c to the collar 13 d of the resin cap 13 is a portion (fitting portion) in which the resin cap 13 is inserted inside one end of the case 12 and closely fitted to the case 12. That is, the distance d ₃ is the thickness of the fitting portion. Since the fitting portion is not involved in the engagement of the case 12 with the potting agent, the pressure resistance performance of the potting agent may be reduced if the distance d ₃ is larger than 2 mm. If the distance d ₃ is 2mm or less, it can maintain the withstand voltage performance of the potting agent. Further, the fitting portion of the resin cap 13 remaining on the case 12 side after cutting can be easily taken out as needed. On the other hand, if the distance d ₃ is 1mm or more, since the contact area between the case 12 can be secured, contact fitting is enhanced.

  The thickness t of the ridge portion 13 d is preferably 1 mm or less. If the thickness t of the ridge portion 13d is 1 mm or less, although it will be described in detail later, even if the ridge portion 13d is left in the hollow fiber membrane module when cut at a predetermined position on a resin cap .

In the resin cap 13 of this example, an injection port 13e for injecting a potting agent is formed at the center of the bottom surface 13b.
In the case of the method shown in FIGS. 5 to 7, since the potting agent is injected from the center tube 16 inserted into the center of the bundle or knitted fabric of the hollow fiber membranes 11, the center tube 16 is obtained for the hollow fiber membrane module obtained. It will remain. Remaining the center tube 16 in the hollow fiber membrane module may limit the applications of the hollow fiber membrane module.
However, as shown in FIGS. 1 and 2, if the injection port 13 e is formed on the bottom surface 13 b of the resin cap 13, the center tube is not necessary for injecting the potting agent. It does not remain, and the application of the hollow fiber membrane module is unlikely to be limited.

  Further, as also shown in FIG. 3, a groove 13 f is formed inside the bottom surface 13 b of the resin cap 13 of this example. If the groove 13f is formed inside the bottom surface 13b of the resin cap 13, the potting agent injected into the case 12 flows through the groove 13f, so that the potting agent can be dispersed uniformly, and the hollow fiber membrane 11 is formed of the case 12 It is hard to be biased within. 1 and 2 are cross-sectional views of the resin cap 13 of FIG. 3 taken along the line a-a '.

The grooves 13 f are preferably formed radially on the bottom surface 13 b of the resin cap 13. In the case where the inlet 13e is formed on the bottom surface 13b, it is preferable that the groove 13f be formed radially from the inlet 13e. If the grooves 13f are radially formed, the potting agent can be easily dispersed uniformly over the entire area of the bottom surface 13b, and can be uniformly filled in the axial direction of the hollow fiber membrane module.
The groove 13 f is preferably formed in a circular shape also in the circumferential direction of the bottom surface 13 b of the resin cap 13. If the groove 13 f is formed in a circular shape, the potting agent can be uniformly dispersed in the circumferential direction of the bottom surface 13 b of the resin cap 13.

The width and depth of the groove 13f are appropriately determined in accordance with the size of the hollow fiber membrane module, the injection amount of the potting agent, and the viscosity, for example, the inner diameter of the case 12 is less than 100 mm, and the potting agent is a urethane resin In some cases, the following configuration is preferable from the viewpoint of uniform dispersion of the potting agent.
That is, the width of the groove 13 f is preferably 3 to 5 mm, and the depth of the groove 13 f is preferably 2 to 4 mm. When the grooves 13f are radially formed, the number of the grooves 13f is preferably 4 to 16.

<Case>
The case 12 accommodates the hollow fiber membrane 11.
The material of the case 12 is not particularly limited, but the method of manufacturing a hollow fiber membrane module of the present invention is particularly effective when the case 12 is difficult to cut. Examples of the material of such a case 12 include polycarbonate, polysulfone, polyphenylene ether, polyethylene, polypropylene, and ABS resin. Among these, polyethylene, polypropylene and an ABS resin are preferable from the viewpoint of excellent injection molding easiness and processability.

<Hollow fiber membrane>
The present invention can be practiced regardless of the structure of the hollow fiber membrane used for the porous membrane, the nonporous membrane, etc. and the constituent material of the hollow fiber membrane.
Examples of the material of the hollow fiber membrane 11 include polyvinyl alcohol, polysulfone, polyvinyl fluoride, polyethylene, polyacrylonitrile and the like.
In particular, a hollow fiber membrane bundle in which the hollow fiber membrane 11 is processed into an interdigital structure is suitably used in that it is excellent in handleability and can be uniformly dispersed and disposed without being biased when stored in the case 12.

<Potting agent>
The potting agent used in the present invention is not particularly limited, and examples thereof include a urethane resin, an epoxy resin, and an unsaturated polyester resin.

<Manufacturing method>
Hereafter, the manufacturing method of the hollow fiber membrane module of this embodiment is demonstrated concretely.
First, hollow fiber membrane 11 is stored in case 12 (storage process). The hollow fiber membranes 11 may be in the form of bundles or in the form of woven fabrics.
Next, the side surface 13a of the resin cap 13 is inserted so as to seal up to the collar 13d inside one end of the case 12 in which the hollow fiber membrane 11 is stored, and one end of the case 12 is sealed with the resin cap 13. Do (attachment process).
Then, a potting agent is injected into the case 12 from the injection port 13e formed on the bottom surface 13b of the resin cap 13 (injection step). Examples of the method for injecting the potting agent include centrifugation and vibration.
Next, after the potting agent is cured, the resin cap 13 is fixed to the resin cap 13 with the cured potting agent and potting agent at a predetermined position on the resin cap 13 (in the example shown, line AA 'of the potting portion 14). The hollow fiber membrane 11 is cut (cutting step) to form an open end of the hollow fiber membrane 11 to obtain a hollow fiber membrane module.
The fitting portion of the resin cap 13 is left buried in the potting agent in the hollow fiber membrane module, and the remaining portion (other than the fitting portion) of the separated resin cap 13 is discarded. Ru.

<Function effect>
According to the manufacturing method of the hollow fiber membrane module of the present embodiment described above, the resin cap which is easy to cut is attached to the end of the cylindrical case for potting, and after curing of the potting agent, the resin cap is mounted. The cured resin is cut at a predetermined position. Therefore, it is not necessary to use a special case having only one end open, and it is not necessary to manufacture a new mold for manufacturing the special case, and the hollow fiber membrane module can be manufactured without extra cost. . In addition, even when the container for containing the hollow fiber membrane is made of a material that is difficult to cut, it is not necessary to use a potting cup made of silicone, so the process of removing the cup can be omitted, and the hollow fiber membrane can be conveniently used. Module can be manufactured.
In addition, since the resin cap used in the present invention has a ridge on the side surface, potting can be performed while suppressing the leakage of the potting agent from the contact portion between the resin cap and the case.

Further, according to the method of manufacturing a hollow fiber membrane module of the present embodiment, since the potting agent is injected from the injection port formed on the bottom surface of the resin cap, the center tube is not required. Therefore, the center tube does not remain in the hollow fiber membrane module, and the use of the hollow fiber membrane module is unlikely to be limited.
Furthermore, according to the manufacturing method of the hollow fiber membrane module of the present embodiment, since the groove 13f as shown in FIG. 3 is formed inside the bottom surface of the resin cap, the potting agent can be uniformly dispersed. The hollow fiber membrane is less likely to be uneven in the case.

Other Embodiments
The manufacturing method of the hollow fiber membrane module of the present invention is not limited to the method described above.
For example, in the illustrated example, the inlet for injecting the potting agent is formed on the bottom of the resin cap, but if it is difficult to inject the potting agent from the bottom of the resin cap, FIG. As shown, an inlet 13 e may be formed on the side surface 13 a of the resin cap 13.
Even when the inlet 13e is formed on the side surface 13a of the resin cap 13, if the groove described above is formed inside the bottom surface 13b of the resin cap, potting injected from the side surface 13a of the resin cap 13 The agent flows through the grooves and is uniformly dispersed.

  Alternatively, a center tube may be inserted into the center of the hollow fiber membrane, and a potting agent may be injected from the center tube. However, as described above, when a center tube is used, the center tube remains in the hollow fiber membrane module to be obtained, which may limit the use of the hollow fiber membrane module. Therefore, it is preferable not to use a center tube for pouring a potting agent, but to form an inlet on the bottom or side of a resin cap and inject the potting agent from the inlet.

  In the method described above, after the hollow fiber membrane is housed in the case, the resin cap is inserted and attached to the case, but after the resin cap is inserted and attached to the case, the hollow fiber membrane is attached to the case You may store in.

  Moreover, although the method mentioned above demonstrated the example which potting a hollow fiber membrane only at the end of a case, you may implement the same method also to the other end of a case. By potting at both ends of the case, a hollow fiber membrane module of a type in which both ends of the hollow fiber membrane are opened can be manufactured.

  EXAMPLES Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto.

"Example 1"
As a case for housing the hollow fiber membrane, a polycarbonate cylindrical case having an outer diameter of 42 mm and an inner diameter of 37 mm was used.
The resin cap, as shown in FIGS. 2 and 3, an outer diameter _{d 1} of the opening 13c is 37 mm, the flange portion 13d outside diameter _{d 2} is 42mm is formed on the side surface 13a, the center of the bottom surface 13b The polyethylene resin cap 13 was used, in which the injection port 13e is formed in the portion, and six grooves 13f and a circular groove 13f radially extending from the injection port 13e are formed inside the bottom surface 13b. The thickness t of the flange portion 13d is 0.5 mm, the distance _{d 3} from the opening 13c of the resin cap 13 to the flange portion 13d was 2 mm. The groove 13f had a width of 3 mm and a depth of 2 mm.
As a potting agent, a urethane resin was used.
The inlet 13e of the resin cap 13 and a container (not shown) filled with the potting agent were connected by a tube (not shown).

As shown in FIG. 1, first, the bundle of hollow fiber membranes 11 was housed in the case 12 (housing step).
Next, the side surface 13a of the resin cap 13 is inserted so as to seal up to the collar 13d inside one end of the case 12 in which the hollow fiber membrane 11 is stored, and one end of the case 12 is sealed with the resin cap 13. Yes (mounting process).
Then, a potting agent is injected into the case 12 by centrifugation from the injection port 13e formed on the bottom surface 13b of the resin cap 13 (injection step), and at the end of the case 12 to which the resin cap 13 is attached. The end of the bundle of hollow fiber membranes 11 was fixed to the case 12.
Then, after the potting agent is cured, the resin cap 13 and the cured potting agent and the hollow fiber membrane 11 fixed with the potting agent are cut along a line A-A 'of the potting portion 14 (cutting step) The open end of the hollow fiber membrane 11 was formed to obtain a hollow fiber membrane module.

In the case of Example 1, since the resin cap 13 having the ridge portion 13d formed on the side surface 13a is used, the side surface 13a of the resin cap 13 is inserted inside the one end of the case 12 so as to seal up to the ridge portion 13d. Then, the collar portion 13d was in close contact with one end of the case 12. Accordingly, the close fitting between the resin cap 13 and the case 12 is further enhanced, and it is possible to suppress the potting agent from leaking from the contact portion between the resin cap 13 and the case 12 even when the potting agent is centrifugally injected.
Moreover, in Example 1, since the potting agent is injected from the injection port 13e formed on the bottom surface 13b of the resin cap 13 without using the center tube, the center tube does not remain in the hollow fiber membrane module, The hollow fiber membrane module which is not restricted in application could be manufactured.
Further, in Example 1, since the groove 13 f is formed inside the bottom surface 13 b of the resin cap 13, the potting agent can be spread inside the case 12. When the potting portion 14 was cut in the longitudinal direction and observed, the potting agent was uniformly dispersed, and the hollow fiber membrane module 11 could be manufactured without deviation of the hollow fiber membrane 11 in the case 12.

"Comparative example 1"
As a case for housing the hollow fiber membrane, a polycarbonate cylindrical case having an outer diameter of 42 mm and an inner diameter of 37 mm was used.
As the resin cap, as shown in FIG. 7, an ABS resin cap 13 having an outer diameter of 37 mm and an inner diameter of 35 mm was used. In addition, the ridge portion is not formed on the side surface of the resin cap 13 used in Comparative Example 1, the injection port is not formed on the bottom surface, and the groove is not formed on the inside of the bottom surface. .
As a potting agent, a urethane resin was used.

As shown in FIG. 7, first, the bundle of hollow fiber membranes 11 was stored in the case 12 (storage step), and the center tube 16 was inserted into the center of the bundle of hollow fiber membranes 11.
Subsequently, the side surface of the resin cap 13 was inserted into the inside of one end of the case 12 in which the hollow fiber membrane 11 was stored, and one end of the case 12 was sealed with the resin cap 13 (mounting step).
Then, a potting agent is injected from the center tube 16 into the case 12 by centrifugation (injection step), and at the end of the case 12 to which the resin cap 13 is attached, the end of the bundle of hollow fiber membranes 11 is It was fixed to case 12.
Then, after the potting agent is cured, the resin cap 13 and the cured potting agent and the hollow fiber membrane 11 fixed with the potting agent are cut by the DD 'line of the potting portion 14 (cutting step) The open end of the hollow fiber membrane 11 was formed to obtain a hollow fiber membrane module.

In the hollow fiber membrane module obtained in Comparative Example 1, traces of leakage of part of the potting agent from the contact portion between the case 12 and the resin cap 13 were observed.
In addition, when the potting portion 14 was cut in the longitudinal direction and observed, a trace in which the potting agent was locally concentrated and flowed in near the tip of the center tube 16 was observed.
In general, the function of the hollow fiber membrane 11 is lost even at the portion where the potting agent and the hollow fiber membrane 11 are in temporary contact with each other, and the performance of the hollow fiber membrane module may be degraded. An appropriate hollow fiber membrane module could not be manufactured.

11 hollow fiber membrane 12 case 13 resin cap 13a side 13b bottom 13c opening 13d ridge 13e inlet 13f groove 14 potting section 15 potting cup 16 center tube

Claims (5)

The hollow fiber membrane is housed in a cylindrical case, one end of the case is sealed with a resin cap consisting of a side surface and a bottom surface, a potting agent is injected into the case and cured to form the hollow fiber membrane and the case. In the method of fixing and manufacturing a hollow fiber membrane module,
A ridge is formed on the side of the resin cap,
Insert the inside of one end of the case so that the side of the resin cap is sealed up to the buttocks, and inject a potting agent,
Between the casing and the flange portion after curing of the potting agent to form an open end of the hollow fiber membranes by cutting the fixed hollow fiber membranes in potting material and the potting agent cured with the resin cap, a hollow fiber Method of manufacturing membrane module.   The manufacturing method of the hollow fiber membrane module of Claim 1 in which the groove | channel is formed inside the bottom face of the said resin-made caps.   The manufacturing method of the hollow fiber membrane module of Claim 2 in which the said groove | channel is radially formed in the bottom face of the said resin-made caps.   The manufacturing method of the hollow fiber membrane module according to any one of claims 1 to 3, wherein an injection port for injecting a potting agent is formed on the bottom surface or the side surface of the resin cap.   The method for manufacturing a hollow fiber membrane module according to claim 4, wherein an injection port for injecting a potting agent is formed on the bottom surface of the resin cap, and the grooves are formed radially from the potting agent injection port.

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