JP2009202112A - Hollow fiber membrane module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hollow fiber membrane module in which effects of formation of a retaining part in a cap, breakage of a potting part and swelling of an annular elastic body by a solvent are suppressed and which therefore has superior liquid-tightness. <P>SOLUTION: The hollow fiber membrane module 1 is provided with a hollow fiber membrane bundle 10, a housing case 20, caps 25 having openings 26, and the annular elastic bodies 50 tightening the attachment of the caps, wherein annular fixing members 40 are disposed in potting parts 30 inside the housing case 20 in such a way that the inner circumferential part of each annular fixing member 40 abuts on an outer circumference of the hollow fiber membrane bundle 10 and is disposed to be located on the center side in the longitudinal direction of the hollow fiber membrane bundle 10 from an opening end 12 of the hollow fiber membrane bundle 10, and wherein each of the annular elastic body 50 is sandwiched by the fixing member 40 and cap 25 and fixed in such a way that the annular elastic body 50 is adjacent to the fixing member 40 and a potting end face 31 is located inside the fixing member 40 in its diametric direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a hollow fiber membrane module.

The hollow fiber membrane module can be used, for example, for degassing dissolved gas in an aqueous solution, an inkjet ink mainly composed of an organic solvent, a resist solution manufacturing process, a flow path in a printer, and the like.
The hollow fiber membrane module bundles bundles of hundreds to tens of thousands of hollow fiber membranes, and the hollow fiber membrane bundles are stored in a cylindrical housing case, and the ends thereof are bonded and fixed by potting parts. The configuration is as follows. As the adhesive fixing method, since the filling rate of the resin is particularly high, a centrifugal method in which a liquid uncured resin is infiltrated between the hollow fiber membranes using a centrifugal force and then cured is often used. As a potting material in the hollow fiber membrane module, an epoxy resin is used from the viewpoint of excellent solvent resistance.

  Also, such a hollow fiber membrane module is used with the end of the housing case (case body) being closed by a cap (header) having an opening. At this time, the housing case and the cap need to be liquid-tightly connected so that the inkjet ink and the resist liquid do not leak from the joint portion thereof. As a method for connecting these liquid-tightly, a method of providing an annular elastic body as a sealing material on the inner surface or side surface of the cap is widely known. A ring-shaped elastic body is sandwiched between the cap and the housing case, and the cap is fixed while being crushed, so that the liquid-tight connection can be achieved. In order to attach the cap in a liquid-tight manner, the annular elastic body needs to be sufficiently crushed.

  As a specific method of using the annular elastic body, a method of arranging the annular elastic body on the potting end surface is often employed from the viewpoint of preventing the formation of a liquid retaining portion inside the cap. However, the potting end face is likely to be scratched or warped by a cutter or the like used for cutting when forming the end face having the open end of the hollow fiber membrane bundle, and also warped when the annular elastic body is pressed. Cheap. Therefore, an annular elastic body such as a gasket having a relatively small tightening pressure cannot completely seal a gap caused by the scratch or warp. Therefore, in this case, since an O-ring or the like having a high tightening pressure is used, a large stress is applied to the potting portion.

  In addition, such a hollow fiber membrane module is, for example, an object to be removed from the voids of the hollow fiber membrane by reducing the pressure outside the hollow fiber membrane while feeding the target liquid into the hollow fiber membrane. It is used in such a manner as to remove. Therefore, in addition to the stress that crushes the annular elastic body, a pressure in the liquid feeding direction due to the liquid feeding of the target liquid and an attractive force in the pressure reducing direction due to the decompression outside the hollow fiber membrane are applied to the potting portion. Therefore, the potting portion has been required to have a sufficiently high strength to prevent breakage.

  As a method for improving the strength of the potting portion, for example, a method of increasing the thickness of the potting portion can be considered. However, in this method, many portions of the hollow fiber membrane bundle are buried in the potting portion, the effective membrane area is reduced, the module performance is lowered, and the operation cost is increased. In addition, since the amount of potting material used increases, the manufacturing cost also increases.

  In addition, a method of arranging an O-ring on the side surface of the end portion of the potting portion is also known from the viewpoint of reducing the load on the potting portion. However, this method tends to form a liquid retention portion inside the cap. For this reason, when this hollow fiber membrane module is used for degassing the target liquid, the manufacture of semiconductors and FPD (Flat Panel Display) from the viewpoints of exacerbation of air bubbles from the module and aggregation of particle components in the resist liquid. It was unsuitable for lines.

Therefore, the following methods are disclosed in order to prevent breakage of the potting portion, improve liquid tightness, and reduce the formation of the staying portion.
A method of forming a groove for disposing an annular elastic body in the potting portion and disposing the annular elastic body in the groove (Patent Documents 1 to 3).
A method of forming a groove for arranging an annular elastic body in the potting portion or arranging the annular elastic body along the outer periphery of the end portion of the potting portion (Patent Document 4).
A method of disposing an annular elastic body on an end surface of a housing case located at an outer peripheral portion of an end portion of a potting portion (Patent Documents 5 and 6)
Japanese Utility Model Publication No. 60-12561 Japanese Patent Publication No. 6-36822 JP 2006-1116048 A JP 2007-175666 A Japanese Patent No. 2668620 Japanese Patent Laid-Open No. 10-165777

However, in the methods of Patent Documents 1 to 3, when the annular elastic body is swollen by a solvent contained in an inkjet ink, a resist solution, or the like, liquid tightness may be lowered. Similarly, in the method of Patent Document 4, liquid tightness may be reduced when swollen by a solvent. Further, in the methods of Patent Documents 5 and 6, a retention portion may be formed between the annular elastic body and the end portion of the potting portion.
Therefore, there is a demand for a hollow fiber membrane module that can suppress the formation of a staying portion in the cap, can sufficiently crush the annular elastic body, and can improve the liquid-tightness by reducing the influence of the solvent.

  Therefore, the present invention has an object of a hollow fiber membrane module having excellent liquid-tightness, in which the formation of a staying portion in a cap, breakage of a potting portion, and the influence of swelling of an annular elastic body due to a solvent are suppressed.

  The hollow fiber membrane module of the present invention is housed in a hollow fiber membrane bundle in which a plurality of hollow fiber membranes are bundled, and the hollow fiber membrane bundle is bonded and fixed in an open state at the potting portion. A housing case and an opening, and a cap attached to the opening end side of the hollow fiber membrane bundle of the housing case, and disposed between the cap and the housing case, and tightly attaching the cap In the hollow fiber membrane module comprising an annular elastic body, an annular fixing member is in contact with the outer periphery of the bundle of hollow fiber membranes, the annular fixing member being in contact with the potting portion inside the housing case, and the hollow fiber membrane It is arranged so as to be located on the center side in the longitudinal direction of the hollow fiber membrane bundle from the opening end of the bundle, and the annular elastic body is adjacent to the fixing member and inside the radial direction, As potting end surface having an open end of the hollow fiber membrane bundle is positioned, characterized in that it is fixed by being sandwiched between the fixing member and the cap.

Further, the hollow fiber membrane module of the present invention includes a distance a along the longitudinal direction of the hollow fiber membrane bundle between the fixing member and the open end of the hollow fiber membrane bundle, and the hollow fiber membrane bundle of the annular elastic body. The ratio (a / b) to the wire diameter b along the longitudinal direction is preferably 0.5 to 1.0.
Moreover, it is preferable that surface roughness Ra of the contact surface with the said annular elastic body of the said fixing member is 1.6a or less.
Further, the inner diameter _{D 2} of the front attachment of the annular elastic member, the dimensional difference between the outer diameter _{D 1} of the said potting end face _(D 2 -D _1), is preferably from 0.1 to 1.0 mm.
Moreover, it is preferable that the material of the said fixing member is a metal or glass.
Moreover, it is preferable that the outer peripheral part of the said fixing member is threaded.
Moreover, it is preferable that R process is given to the protrusion corner part located in the edge part of the inner peripheral part of the said fixing member.

  In the hollow fiber membrane module of the present invention, formation of a staying portion in the cap is suppressed. Further, the potting portion can be prevented from being damaged, the influence of swelling of the annular elastic body by the solvent can be suppressed, and excellent liquid tightness is exhibited.

[Hollow fiber membrane module]
FIG. 1 is a cross-sectional view showing an example of an embodiment of a hollow fiber membrane module of the present invention. The hollow fiber membrane module 1 of the present embodiment includes a hollow fiber membrane bundle 10 in which a plurality of hollow fiber membranes 11 are bundled, a housing case 20 that houses the hollow fiber membrane bundle 10, and a cap 25 that is attached to the housing case 20. The fixing member 40 that fixes the hollow fiber membrane bundle 10 inside the housing case 20 and the annular elastic body 50 that is disposed between the housing case 20 and the cap 25 and tightly attaches the cap 25 are provided. .

  The hollow fiber membrane bundle 10 is held by being bonded and fixed in a state where the end portions of the hollow fiber membranes 11 are opened in the potting portion 30 (hereinafter, this end portion is referred to as the open end portion 12). The primary side and the secondary side of 20 are separated. Further, the annular elastic body 50 is adjacent to the fixing member 40 and inside the radial direction thereof, the fixing member 40 and the cap 25 so that the potting end surface 31 having the open end portion 12 of the hollow fiber membrane bundle 10 is located. It is sandwiched between and fixed.

(Hollow fiber membrane)
The hollow fiber membrane 11 is an internal hollow thin tube, and has a porous tube wall in which an infinite number of holes are formed. For example, the target liquid can be degassed by reducing the pressure while supplying the target liquid into the hollow fiber membrane 11. The hollow fiber membrane 11 is preferably a polyolefin-based hollow fiber membrane such as polypropylene, polyethylene, or poly (4-methylpentene-1) from the viewpoint of excellent solvent resistance.

As the structure of the hollow fiber membrane 11, for example, a structure having a three-layer structure in which a non-porous homogeneous layer having gas permeability is sandwiched between porous support layers from both sides (hereinafter referred to as a three-layer composite hollow fiber membrane). And those having a two-layer structure in which a support layer is provided only on the outside or inside of the homogeneous layer.
If the polyolefin resin constituting the homogeneous membrane having gas permeability is within a range that does not adversely affect the damage or liquid tightness of the potting part 30 and does not deteriorate the module performance (degassing performance, etc.) excessively. If necessary, additives such as an antioxidant, an ultraviolet absorber, a lubricant, an antiblocking agent, a colorant, a flame retardant and the like may be added.

The melt flow rate (MFR) of the polyolefin resin constituting the homogeneous membrane of the hollow fiber membrane 11 is preferably 0.1 to 5 g / 10 min, and more preferably 0.3 to 2 g / 10 min. . However, MFR is a value measured at a test temperature of 190 ° C. and a test load of 2.16 kgf in accordance with ASTM D1238 E condition.
If the MFR is 0.1 g / 10 min or more, the extrusion moldability will be good. Further, if the MFR is 5 g / 10 min or less, the fluidity of the polymer does not become too high, so that the homogeneity of the homogeneous membrane due to the flow of the homogeneous membrane resin to the support layer side is prevented. When the hollow fiber membrane 11 is used as a deaeration membrane, the gas permeation performance can be sufficiently maintained.

The three-layer composite hollow fiber membrane is produced, for example, through a multilayer composite spinning process and a stretched porous process. Specific examples of the production method include the following methods.
First, a molten polymer (high-density polyolefin, etc.) for the support layer precursor (unstretched layer) is supplied to the outermost layer nozzle portion and innermost layer nozzle portion of the concentric composite nozzle nozzle, and the homogeneous layer is melted to the intermediate layer nozzle portion. Supply polymer (polyolefin resin). Then, the molten polymer is extruded from the concentric composite nozzle nozzle and cooled and solidified in a drafted state to obtain unstretched hollow fibers. Next, this unstretched hollow fiber is stretched to make the inner layer and outer layer sandwiching the homogeneous membrane of the intermediate layer porous.
As a result, a three-layer composite hollow fiber membrane having a homogeneous membrane and a support layer (inner layer and outer layer) that supports it is obtained.

A hollow fiber membrane bundle 10 is obtained by bundling a plurality of such hollow fiber membranes 11. The number of hollow fiber membranes 11 forming the hollow fiber membrane bundle is not particularly limited.
The hollow fiber membrane bundle 10 of the present embodiment is held in a state in which the vicinity of both open end portions 12 of each hollow fiber membrane 11 is embedded in the potting portion 30. That is, both open end portions 12 of the hollow fiber membrane bundle 10 are supported by the potting unit 30 so as to face the stock solution supply side region when the hollow fiber membrane module 1 is used. The portion that is not embedded is housed in the center of the housing case 20.

The filling rate of the hollow fiber membrane 11 is preferably in the range of 40 to 70%. However, the filling rate of the hollow fiber membrane 11 means that the total outer contour area of the cross section of the hollow fiber membrane 11 in the housing case 20 is the transverse area of the inner wall of the housing case 20 (the space for housing the hollow fiber membrane bundle 10). As a percentage of
If the filling rate of the hollow fiber membrane 11 is 40% or more, it is easy to prevent the hollow fiber membrane bundle 10 from being bent in the housing case 20. Moreover, if the filling rate of the hollow fiber membrane 11 is 70% or less, it is easy to prevent the hollow fiber membrane bundle 10 from being flattened.

(Housing case)
The housing case 20 is a case for housing the hollow fiber membrane bundle 10, and examples thereof include a module case and a cartridge case. In the housing case 20, a vacuum port 22 for reducing the pressure inside the housing case 20 is formed in the case body 21. In addition, the cap 25 is formed with an opening 26 serving as a processing target liquid inflow / outlet.

There is no restriction | limiting in particular in the material of the housing case 20, According to the chemical resistance calculated | required by each use, it can select suitably and can be used. Specific examples include polyolefins such as polyethylene, polypropylene, and poly (4-methylpentene-1), polysulfone, and modified polyphenylene oxide. Further, when the adhesiveness with the potting material is low, the contact portion may be subjected to a surface treatment such as a primer treatment or a plasma treatment.
There is no restriction | limiting also about the thickness of the housing case 20, What is necessary is just to select suitably with the water pressure at the time of using the hollow fiber membrane module 1. FIG.

  Further, it is preferable that a threaded portion 23 is provided in a portion of the housing case 20 where the potting portion 30 is formed so that the fixing member 40 can be screwed. Further, when the ring-shaped fixing member 40 is fixed by screwing, it is preferable that the housing case 20 is provided with a screw escape portion 24 so that the housing case 20 is not screwed too hard and an excessive load is applied to the housing case 20.

(Potting part)
The potting portion 30 holds the hollow fiber membrane bundle 10 in a state where the end portion is opened, that is, in a state where the potting end surface 31 has the open end surface 12, and at the primary side region which is the inner side of the housing case 20 and the outer side. It is provided so as to separate a certain secondary region.
As a potting material forming the potting portion 30, it is preferable to use an epoxy resin from the viewpoint of solvent resistance, water resistance (reduction of swelling), and the like.
Examples of the curing agent for curing the potting material include aliphatic amines, aromatic amines, organic acid anhydrides, and modified amines. Among these, it is preferable to use an aliphatic polyamine. Further, a reaction retarder may be added in order to suppress a rapid progress of the curing reaction of the potting material.

The viscosity of the potting material may be a viscosity that does not impair the permeability to the hollow fiber membrane bundle 10. When the potting material penetrates into the voids in the hollow fiber membrane bundle 10, an anchor effect is exhibited, and the adhesive force of the hollow fiber membrane bundle 10 to the potting part 30 is improved. Moreover, when using the hollow fiber membrane module 1 as a deaeration hollow fiber membrane module, it is preferable that the filling rate of a potting material is especially high. Therefore, the potting part 30 in the hollow fiber membrane module 1 is manufactured by the centrifugal potting method generally used for forming the potting part. Since the centrifugal potting method uses centrifugal force, the potting material can easily penetrate into the voids in the hollow fiber membrane bundle 10 even if the viscosity is higher than that of the stationary method.
It is preferable that the viscosity of the potting material when forming the potting part 30 by the centrifugal potting method is 100 to 2000 mPa · s.

  Moreover, it is preferable that the hollow fiber membranes 11 of the hollow fiber membrane bundle 10 in the potting part 30 are evenly dispersed inside the fixing member 40. When the hollow fiber membrane 11 is locally unevenly distributed in the potting portion 30, the hollow fiber membrane 11 is flattened at a portion with a high filling rate or the potting material is difficult to penetrate, while the filling rate is low. In the portion, the heat generated when the potting material is cured increases, and the stress accompanying the curing shrinkage increases, which may cause damage.

In general, the load resistance applied to the potting portion of the hollow fiber membrane module is affected by the bonding strength between the potting portion and the housing case and the bonding area thereof. This influence is particularly great when a resin housing case is used. Since the bending strength of the potting material forming the potting portion is sufficiently large, such as several tens of MPa, the rigidity of the potting portion is sufficiently high.
In order to provide sufficient strength at the potting portion when a resin housing case is used, it is necessary to increase the bonding area because the bonding strength is usually low. However, in this method, the amount of potting material used to form the potting portion is increased, and heat generation during curing is significantly increased, resulting in an increase in residual stress accompanying curing shrinkage. If a metal housing case with high bonding strength with the potting part is used, the strength can be increased with a small amount of potting material, but the hollow fiber membrane module can be used for precision applications such as FPD (Flat Panel Display) and liquid crystal. When used, defects due to metal elution are likely to occur.
In the hollow fiber membrane module of the present invention, since the potting part 30 is bonded and fixed to the fixing member 40 using the fixing member 40, the adhesive strength in the potting part 30 can be sufficiently increased even if the resin housing case 20 is used. .

(Fixing member)
The fixing member 40 has an annular shape, and due to its high adhesive force, damage or peeling of the potting portion 30 is reduced in response to a hydraulic or pneumatic load applied to the potting portion 30.
The fixing member 40 preferably has a function of radiating the heat generated from the potting portion 30 to the surroundings or having excellent thermal conductivity. Thereby, excessive heat generation at the time of hardening formation of the potting part 30 can be suppressed, and suppression of hardening shrinkage of the potting material and relaxation of stress due thereto can be facilitated. Specifically, the material of the fixing member 40 is a metal such as stainless steel (thermal conductivity: 16.7 W / m · K), aluminum (thermal conductivity: 236 W / m · K), or glass (thermal conductivity: 1 W / m · K) is preferable.

The fixing member 40 preferably has a high adhesive strength to the potting material from the viewpoint of reducing the amount of resin used for the potting portion 30 while maintaining the adhesive strength. For example, when the potting material is an epoxy resin (trade name: Araldite 2020, manufactured by Huntsman Advanced Materials), stainless steel (SAS316, adhesive strength: 24 N / mm ² ), aluminum alloy (L165, adhesive strength: 16 N / mm) ²⁾ brass (adhesive strength: 14N / ^mm 2), glass (adhesive strength: 26N / mm ^2), and the like. However, the adhesive strength in the parenthesis is the adhesive strength when the single overlap amount is 20 mm × 15 mm in accordance with JIS K6850. These are excellent in adhesive strength as compared with a resin member such as polypropylene (1.5 N / mm ² ).
The material of the fixing member 40 is preferably metal or glass from the viewpoint of adhesive strength and solvent resistance.

  The fixing member 40 is disposed in the housing case 20 so that the hollow fiber membranes 11 are bundled in the potting portion 30 and the inner peripheral portion thereof is in contact with the outer periphery of the hollow fiber membrane bundle 10. Further, the fixing member 40 is disposed so as to be positioned on the center side in the longitudinal direction of the hollow fiber membrane bundle 10 with respect to the opening end surface 12 (potting end surface 31) of the hollow fiber membrane bundle 10.

  Further, in the hollow fiber membrane module 1, a portion where the fixing member 40 inside the housing case 20 is arranged extends outward, and the fixing member 40 is in that portion, and the inner diameter c (FIG. 2) of the fixing member 40 is the housing case 20. The inner diameter (the inner diameter of the portion 21a for housing the hollow fiber membrane bundle 10 portion not bonded and fixed by the potting material) is preferably arranged. This makes it easy to prevent the hollow fiber membrane 11 from being bent when the potting material 30 is formed by filling the potting material by centrifugal potting, and the hollow fiber membrane bundle 10 can be easily inserted into the housing case 20. .

  The fixing member 40 is adjacent to the annular elastic body 50. Therefore, it is preferable that the contact surface 41 is smooth from the viewpoint that sufficient liquid tightness can be obtained even if the tightening pressure of the cap 25 is relatively low. Specifically, it is preferable that the arithmetic average roughness Ra, which is a parameter representing the surface roughness, in each part randomly extracted from the surface of the object described in JIS B 0601 is 1.6a or less.

Further, the outer peripheral portion of the fixing member 40 is threaded so as to correspond to the threaded portion 23 applied to the housing case 20 so that the fixing member 40 can be screwed to the housing case 20. preferable. Accordingly, it becomes easy to prevent the fixing member 40 from dropping and moving when the potting portion 30 is formed by the centrifugal potting method.
Further, when the fixing member 40 is fixed to the housing case 20, the potting material is applied as an adhesive to the fixing member 40 or the threaded portion of the housing case 20, and the fixing member 40 is bonded and fixed, or made of a fluorine-based resin for piping. It is preferable that the sealing tape is wound around the fixing member 40 and then screwed.

  The outer diameter d (FIG. 2) of the fixing member 40 is preferably 2 to 10 mm thicker than the outer diameter of the hollow fiber membrane bundle 10. If the outer diameter d of the fixing member 40 is 2 mm or more larger than the outer diameter of the hollow fiber membrane bundle 10, it is easy to thread the outer peripheral portion of the fixing member 40. Further, when the outer diameter d of the fixing member 40 is larger than 10 mm with respect to the outer diameter of the hollow fiber membrane bundle 10, the outer diameter of the hollow fiber membrane module 1 is increased, and there is a possibility that a staying portion is generated in the vicinity of the potting end surface 31. is there.

Further, a groove or the like for improving the adhesiveness between the potting portion 30 and the hollow fiber membrane bundle 10 may be provided in the inner peripheral portion of the fixing member 40.
In addition, it is easy to prevent the hollow fiber membrane 11 from being damaged due to contact when the hollow fiber membrane bundle 10 is inserted into the protruding corner portions 42 and 43 located at the end of the inner peripheral portion of the fixing member 40. , R processing is preferably performed. However, the R processing is processing in an arc shape so as to eliminate corners as shown in FIG.

(Annular elastic body)
The annular elastic body 50 is disposed between the housing case 20 and the cap 25 and plays a role of tightly attaching the cap 25.
The material of the annular elastic body 50 is preferably a rubber or an elastomer such as silicon rubber, fluorine rubber, acrylonitrile butadiene rubber (NBR), etc. from the viewpoint that high liquid-tightness can be exhibited with a repulsive force against pressing.
The size, rubber hardness and crushing amount of the annular elastic body 50 are arbitrary, but if the repulsive force against crushing is excessive, a part of the partition wall of the housing case 20 (attachment portion of the fixing member 40 of the housing case 20 etc.) Will receive a large pressing force for a long time. Accordingly, when the partition wall is deformed due to the creep phenomenon, the liquid tightness may be deteriorated. The crushing amount of the annular elastic body 50 is preferably about 10 to 20% with respect to the wire diameter from the viewpoint that the liquid tightness can be stably maintained.

  The annular elastic body 50 is fixed so as to be squeezed between the fixing member 40 and the cap 25 so that the potting end surface 31 is located adjacent to the fixing member 40 and inside the radial direction. Thereby, liquid-tightness improves. In the hollow fiber membrane module 1, since the stress that crushes the annular elastic body 50 is not directly applied to the potting portion 30, damage to the potting portion 30 due to the stress can be suppressed. Further, since the annular elastic body 50 can be sufficiently crushed, excellent liquid tightness can be obtained.

If the distance between the annular elastic body 50 and the potting portion 30 on the radially inner side is too large, a staying portion is easily formed in the space formed therebetween, and the flow in the hollow fiber membrane module 1 is deteriorated. . Therefore, the annular elastic body 50 is preferably installed at a position close to the potting portion 30 from the viewpoint of allowing the resist solution or the like to quickly flow into the hollow fiber membrane bundle 10. In the hollow fiber membrane module 1, the annular elastic body 50 is particularly preferably fixed so that the inner peripheral portion thereof is in contact with the outer periphery of the potting portion 30.
The dimensional difference (D ₂ −D ₁ ) between the inner diameter (D ₂ ) before the annular elastic body 50 is fixed and the outer diameter (D ₁ ) of the potting end surface 31 is 0.1 mm to 1.0 mm. preferable. If the dimensional difference (D ₂ −D ₁ ) is 0.1 mm or more, it is easy to prevent the hollow fiber membrane bundle 10 from being loaded when the annular elastic body 50 is attached. If the dimensional difference (D ₂ -D ₁ ) is 1.0 mm or less, the fixing member 40 exposed between the annular elastic body 50 and the potting portion 30 particularly when the metal fixing member 40 is used. Therefore, it is easy to prevent the metal component from eluting into the liquid to be treated.

  In the hollow fiber membrane module 1 of the present embodiment, the distance a along the longitudinal direction of the hollow fiber membrane bundle 10 between the fixing member 40 and the open end 12 of the hollow fiber membrane bundle 10, and the hollow fiber membrane of the annular elastic body 50. The ratio (a / b) to the wire diameter b along the longitudinal direction of the bundle 10 is preferably 0.5 to 1.0 (FIG. 2). If a / b is 0.5 or more, when the annular elastic body 50 is disposed outside the potting portion 30 in the radial direction, a positional shift along the radial direction of the annular elastic body 50 hardly occurs. Further, if a / b exceeds 1.0, a staying portion may be formed between the outer end surface of the annular elastic body 50 and the potting portion 30.

[Production method]
Hereinafter, the manufacturing method of the hollow fiber membrane module 1 of this embodiment is demonstrated.
The housing case 20 and the fixing member 40 are preferably dried after being washed with alcohol or toluene and degreased. Further, the housing case 20 is subjected to a surface treatment or the like according to the material.
After applying an adhesive to the threaded portion 23 of the housing case 20, the fixing member 40 is screwed into the housing case 20 and fixed and screwed.

  The hollow fiber membrane bundle 10 is produced by making a predetermined number of hollow fiber membranes 11 into a knitted product by Russell knitting. Next, the hollow fiber membrane bundle 10 is inserted and accommodated in the housing case 20 to which the fixing member 40 is bonded so that the hollow fiber membranes 11 are slid together. At this time, the hollow fiber membranes 11 are restrained by the fixing member 40 and the housing case 20, so that they are prevented from spreading and bending. Thereafter, heat treatment is performed so that the hollow fiber membrane bundle 10 has a predetermined length. By this heat treatment, the hollow fiber membrane bundle 10 can be made to have a predetermined length, and damage during insertion of the hollow fiber membrane bundle 10 can be reduced. That is, even when the hollow fiber membrane bundle 10 is inserted in a state of being crushed by mistake at the time of insertion, the wrinkles can be removed by this heat treatment.

Next, a potting material is injected into the housing case end 27 side by a centrifugal potting material injection device and cured to form a potting portion 30 having a predetermined thickness. The amount of resin when pouring the potting material is such that the interface of the formed potting end portion 32 is positioned inside the fixing member 40 in the radial direction, that is, between the protruding corner portion 42 and the protruding corner portion 43 of the fixing member 40. To. It is preferable that the interface of the potting end portion 32 is aligned with the protruding corner portion 42 in terms of obtaining high adhesive strength. By positioning the interface of the potting end portion 32 in this manner, it is possible to suppress the occurrence of a resin rising portion (a portion where the potting material has been scooped up) and the occurrence of a leak at that portion. Further, the bending of the hollow fiber membrane bundle 10 can be suppressed.
Further, by keeping the potting part 30 from being close to the vacuum port 22, it is easy to prevent the hollow fiber membrane bundle 10 from being pulled in the outer peripheral direction and bent near the interface of the potting part 30 to cause a leak.

The curing time of the potting material is preferably 48 hours or less, and more preferably 24 hours or less from the viewpoint of production efficiency. The curing time can be controlled by the type of curing agent, the amount used, and the like.
The centrifugal force to be loaded is preferably in the range of x10 g to x40 g. If the centrifugal force is 40 g or less, the potting material injection speed becomes higher than the speed at which the potting material penetrates between the hollow fiber membranes 11, and the curing proceeds with the hollow fiber membrane 11 having a low specific gravity raised. Therefore, it is easy to prevent the hollow fiber membrane 11 from being unevenly distributed. As a result, the hollow fiber membrane bundle 10 is unlikely to be bent in the vicinity of the potting portion, and the pressure resistance is improved. If the centrifugal force is 10 g or more, the speed at which the potting material is injected between the hollow fiber membranes 11 becomes too small compared to the speed at which the potting material penetrates, and the capillary phenomenon appears strongly and the hollow fiber membrane bundle 10 It is easy to prevent the effective membrane area from decreasing due to the creeping of the potting material.
Further, a member such as a distribution plate having a small porosity of 0.5 to 5 mm may be used for the purpose of reducing the injection speed of the potting material while maintaining the centrifugal force.

Next, after curing for bringing out the final physical properties to the potting portion 30 and solidifying it, the end surface of the potting portion 30 on the opening end portion 27 side is cut to form a flat surface to form an end of each hollow fiber membrane 11. Open the part. Thereby, even when the end portion of the hollow fiber membrane 11 is blocked by the potting material, it is removed and the open end portion 12 can be exposed to the outside of the case body 21 of the housing case 20. . At this time, the fixing member 40 is positioned at the center side by a distance a closer to the center side in the longitudinal direction of the hollow fiber membrane bundle 10 than the opening end portion 12.
Next, the annular elastic body 50 is arranged so that the potting end 31 is located adjacent to the fixing member 40 and inside the radial direction, and is sandwiched between the fixing member 40 and the cap 25 so as to be crushed. The cap 25 is attached so that 50 is fixed.
The hollow fiber membrane module 1 is obtained by the above method.

  In the manufacture of the hollow fiber membrane module, when the potting end face is opened, if it is cut with a cutter or the like, the end face may be tilted or scratched due to escape by the blade. Therefore, in order to position the annular elastic body on the end surface of the potting to improve the liquid tightness, it is necessary to fill the flaws and the like, and it is necessary to increase the tightening pressure of the annular elastic body. Therefore, in the conventional method, a large load is applied to the potting portion, causing damage.

On the other hand, in the hollow fiber membrane module of the present invention, since the annular elastic body 50 is fixed so as to be in contact with the fixing member 40, the annular elastic body 50 can be crushed without applying a load to the potting portion 30, thereby being excellent. Liquid tightness is obtained. Further, sufficient liquid tightness can be obtained even at a relatively low tightening pressure.
Further, in the hollow fiber membrane module 1 of the present invention, the annular elastic body 50 is arranged so that the potting end surface 31 is located on the inner side in the radial direction. And swelling can be suppressed. Further, since the fixing member 40 is not easily affected by the swelling, even if the annular elastic body 50 is swollen, the influence is small. Further, by arranging the annular elastic body 50 in this way, it is possible to suppress the generation of a space in which a stay portion is formed in the cap 25.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. However, the present invention is not limited by the following description.
[Example 1]
A method for manufacturing the hollow fiber membrane module 1 illustrated in FIG. 1 will be described below.
Soft polypropylene Zelas 7023 (manufactured by Mitsubishi Chemical) as the intermediate layer, polypropylene homopolymer Novatec FY6H (manufactured by Nippon Polypro) as the support layer, and spinning with a three-layer composite nozzle that forms an intermediate layer between the two support layers, unstretched A hollow fiber was obtained.
This unstretched hollow fiber was annealed at 140 ° C., then stretched 1.25 times at 23 ± 2 ° C., and subsequently stretched 3.3 times in a 130 ° C. heating furnace, In the heating furnace, a relaxation step of 0.3 times was provided, and finally the total draw ratio (magnification from the undrawn hollow fiber) was formed to be 3 times to obtain a multilayer composite hollow fiber membrane for deaeration ( A hollow fiber membrane 11) was obtained. The hollow fiber membrane 11 had a three-layer structure in which a homogeneous membrane (non-porous thin film) was sandwiched between two porous layers.
Also, a housing case made of polypropylene (manufactured by Nippon Polypro, Wintec WMG03, MFR (210 ° C.): 30 g / 10 min), the inner diameter of the hollow fiber membrane bundle housing part (21a) is φ74, and the inner diameter of the threaded part 23 is 80φ. 20 was prepared by cutting. A screw escape portion 24 of 10 mm is provided in the longitudinal direction of the housing case for the escape at the time of threading inside the threaded portion 23.
The same resin used as the potting material, the same epoxy resin Araldite 2020 manufactured by Huntsman Advanced Materials, is applied to the threaded portion 23 as an adhesive, and an aluminum alloy fixing member 40 (φ80-φ74) is applied to the end of the housing case 20 Screwed in and fixed.
Subsequently, a hollow fiber membrane bundle 10 having a three-layer structure was formed by raschel knitting to form a hollow fiber membrane bundle 10 and inserted into the housing case 20. Furthermore, it processed at 100 degreeC which is below the softening point of a support layer so that it may become predetermined length with a dry-type incubator.
Next, a potting jig is installed on the case main body 21 of the housing case 20, and after filling the case main body 21 with 100 g of epoxy resin Araldite 2020 (manufactured by Huntsman Advanced Materials) as a potting material, Was set in a centrifugal membrane module manufacturing apparatus with the jig and centrifuged and cured at x30 G. Thereafter, curing was performed at 40 ° C. under conditions of 7 hours so that the final physical properties were obtained. The distance a between the fixing member 40 and the open end 12 of the hollow fiber membrane bundle 10 was 2.5 mm (a / b = 0.8), and the end of the housing case 20 was opened with a large cutter.
An O-ring G75 (manufactured by NOK, wire diameter: 3.1 mm) is used as the annular elastic body 50, and is arranged so that the potting end face 31 is positioned inside the radial direction, and a cap 25 is attached to the hollow fiber membrane module 1. Got.

[Comparative Example 1]
Except for using the large cutter to open the end of the housing case 20 so that the end face of the housing case 20 and the open end face 12 (potting end face 31) of the hollow fiber membrane bundle 10 are aligned without using the fixing member 40. A hollow fiber membrane module 2 (FIG. 3) was prepared in the same manner as in Example 1.

[Repeated pressure test]
The pressure resistance test was repeatedly performed on the hollow fiber membrane modules of Example 1 and Comparative Example 1.
In this test, for each of the hollow fiber membrane modules, one end face side of the potting portion is closed, and the target liquid is supplied to the raw water supply line while being suctioned from the vacuum port, and water pressure is intermittently applied. The presence or absence of occurrence of cracks in the potting portion, the interface between the potting portion and the housing case, and the number of times of water pressure application when a leak occurred due to the crack or separation were measured.
Specifically, after the hollow fiber membrane modules obtained in the examples and comparative examples are placed in a thermostatic bath at 25 ° C., the hot water in the thermostatic bath is pumped up, and an inkjet printer at 0.4 [MPa] The water-based ink solution is injected and pressurized on the primary side of the hollow fiber membrane module, and then the pressure is reduced to 0 [MPa]. This pressurization and depressurization were repeated as 1 cycle at a cycle of 1 cycle / second. The pressurization and depressurization were performed by switching the valve body, and the pressurization and depressurization were repeated while maintaining each hollow fiber membrane module at 25 ° C.
Table 1 shows the results of the repeated pressure resistance test.

As shown in Table 1, the hollow fiber membrane module 1 of Example 1 did not leak even at the time of pressurization for 200000 cycles in the repeated pressure resistance test.
On the other hand, in the hollow fiber membrane module 2 of Comparative Example 1, when the pressure was repeated 20000 times in the repeated pressure resistance test, leakage occurred at the portion of the hollow fiber membrane slightly in the longitudinal direction of the hollow fiber membrane bundle 10 from the potting end surface 32. There has occurred.

  The hollow fiber membrane module of the present invention has excellent liquid-tightness because it suppresses the influence of the formation of the retention part in the cap, the damage of the potting part, and the swelling of the annular elastic body due to the solvent. It can be suitably used for inkjet inks containing an organic solvent as a main component, a process for producing a resist solution, degassing of dissolved gas in a flow path, etc. in a printer.

It is sectional drawing which showed an example of embodiment of the hollow fiber membrane module of this invention. It is an expanded sectional view of the edge part of the hollow fiber membrane module of FIG. 3 is a cross-sectional view showing a hollow fiber membrane module of Comparative Example 1. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Hollow fiber membrane module 10 Hollow fiber membrane bundle 11 Hollow fiber membrane 12 Open end 20 Housing case 25 Cap 30 Potting part 40 Fixing member 41 Contact surface 50 Annular elastic body

Claims (7)

A hollow fiber bundle in which a plurality of hollow fiber membranes are bundled, a housing case in which the hollow fiber membrane bundle is bonded and fixed in an open state at the potting portion, and has an opening. A hollow fiber comprising: a cap attached to the open end of the hollow fiber membrane bundle of the housing case; and an annular elastic body disposed between the cap and the housing case for tightly attaching the cap. In the membrane module,
An annular fixing member is in contact with the outer periphery of the hollow fiber membrane bundle at the potting portion inside the housing case, and the hollow fiber membrane bundle is more than the open end of the hollow fiber membrane bundle. It is arranged to be located on the center side in the longitudinal direction,
The annular elastic body is sandwiched and fixed between the fixing member and the cap so that the potting end surface having the open end of the hollow fiber membrane bundle is located adjacent to the fixing member and inside the radial direction. A hollow fiber membrane module characterized by comprising:   Ratio of distance a along the longitudinal direction of the hollow fiber membrane bundle between the fixing member and the open end of the hollow fiber membrane bundle, and the wire diameter b along the longitudinal direction of the hollow fiber membrane bundle of the annular elastic body The hollow fiber membrane module according to claim 1, wherein (a / b) is 0.5 to 1.0.   The hollow fiber membrane module according to claim 1 or 2, wherein a surface roughness Ra of a contact surface of the fixing member with the annular elastic body is 1.6a or less. The inner diameter _{D 2} before being fixed said annular elastic member, the dimensional difference between the outer diameter _{D 1} of the said potting end face _(D 2 -D _1), is 0.1 to 1.0 mm, according to claim 1 4. The hollow fiber membrane module according to any one of 3.   The hollow fiber membrane module in any one of Claims 1-4 whose material of the said fixing member is a metal or glass.   The hollow fiber membrane module in any one of Claims 1-5 by which the threading process is given to the outer peripheral part of the said fixing member.   The hollow fiber membrane module in any one of Claims 1-6 by which R process is given to the protrusion corner part located in the edge part of the inner peripheral part of the said fixing member.

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