Hollow fiber membrane module and method for producing same

Abstract

A hollow fiber membrane module (10) is provided with a hollow fiber membrane bundle (11) and a housing case (15). The housing case (15) includes a first molded member (17) and a second molded member (18). In the first molding member (17), the cylindrical portion (19) and the nozzle portion (20) are integrally molded. The second molded member (18) has a tubular shape that is coaxial and continuous with the tubular portion (19). In the axial direction, the values obtained by dividing the wall thickness of the housing case (15) by the wall thickness of the second molded member (18) are 1.0-1.3 and 1.0-1.5, respectively, at positions at which the distance from the joining position to the first molded member (17) side is 3 times and 5 times the wall thickness of the second molded member (18), respectively.

Description

This application is a divisional application of the Chinese patent application with application number 202080086968.4 (application date: December 17, 2020, invention name: hollow fiber membrane component and its manufacturing method). CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority from Japanese Patent Application No. 2019-229701 filed in Japan on December 19, 2019, and the entire disclosure of the prior application is incorporated herein by reference. Technical Field

[0002] The present invention relates to a hollow fiber membrane module, and in particular to a hollow fiber membrane module with improved pressure resistance. Background Art

[0003] Hollow fiber membranes are known as membranes used in membrane filtration methods using microfiltration membranes and ultrafiltration membranes in applications such as gas-liquid absorption, degassing, and filtration. Membrane modules using hollow fiber membranes are widely used in various membrane separation applications because of their large membrane area and the ability to miniaturize the device. As their main membrane modules, a membrane module including a hollow fiber membrane bundle is known, which is composed of a plurality of hollow fiber membranes fixed at both ends by a resin portion.

[0004] In order to increase the processing capacity of a single hollow fiber membrane module, a study is being conducted to enlarge the housing body that accommodates the hollow fiber membrane bundle, thereby enlarging the hollow fiber membrane module. The housing body is, for example, a resin molded product, and the larger it is, the more difficult it is to mold it from a single component. Therefore, it is known that the housing body is formed by combining divided parts (see Patent Document 1). Prior art literature Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-051451 Summary of the invention Problems to be solved by the invention

[0006] During filtration operation, a positive pressure is applied from the inside to the outside of the housing body accommodating the hollow fiber membrane bundle, and the housing body is required to have pressure resistance corresponding to the operating conditions. In particular, in the housing body formed by combining multiple parts, it is easy to break from the combined part, and in order to improve the overall pressure resistance, it is also necessary to improve the pressure resistance of the combined part. Means used to solve problems

[0007] The inventors of the present invention have conducted intensive studies on the above-mentioned problems and have found that the above-mentioned problems can be solved by reducing the stress concentration on the joint portion in the housing case of the hollow fiber membrane module, thereby completing the present invention. That is, the present invention is as follows. [1] A hollow fiber membrane module, comprising: A hollow fiber membrane bundle, wherein the hollow fiber membrane bundle is formed by bundling a plurality of hollow fiber membranes; and The outer shell has a first molding component and a second molding component, and accommodates the hollow fiber membrane bundle, the first molding component is integrally formed by a cylindrical part and a nozzle part whose inner cavity is connected to the cylindrical part, and the second molding component is a cylindrical shape that is coaxial and continuous with the cylindrical part, The total length of the housing in the axial direction exceeds 1 m. In the axial direction, the values ​​of the wall thickness of the outer shell shell divided by the wall thickness of the second molding member at positions where the distances from the combined position of the first molding member and the second molding member to the first molding member side are 3 times and 5 times the wall thickness of the second molding member, respectively, are 1.0 to 1.3 and 1.0 to 1.5. [2] The hollow fiber membrane module according to [1] is characterized in that the second molding member is cylindrical with an inner diameter of 150 mm or more. [3] The hollow fiber membrane module according to [2] is characterized in that the second molding member is cylindrical with an inner diameter of 200 mm or more. [4] The hollow fiber membrane module according to any one of [1] to [3], wherein the membrane module is ruptured starting from a portion other than the joining position by pressurizing the interior of the outer shell. [5] The hollow fiber membrane assembly according to any one of [1] to [4] is characterized in that the first molding member and the second molding member are molded from at least one resin material selected from ABS resin, polyvinyl chloride, polyphenylene ether, polypropylene, polysulfone, polyethersulfone, and polyphenylene sulfide. [6] The hollow fiber membrane module according to any one of [1] to [5], wherein the first molding member and the second molding member are molded from the same resin material. [7] The hollow fiber membrane module according to any one of [1] to [6], wherein at least one of the first molding member and the second molding member is molded from a resin material mixed with glass fibers. [8] A method for manufacturing a hollow fiber membrane module according to any one of [1] to [7], comprising: forming the outer shell by butting the first molding member and the second molding member. [9] The manufacturing method according to [8], further comprising: bonding the first molding member and the second molding member by any one of heating, contact heating, and an organic solvent. Effects of the Invention

[0008] According to the present invention, a hollow fiber membrane module having improved overall pressure resistance can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a longitudinal sectional view showing a hollow fiber membrane module according to one embodiment of the present invention. Figure 2 It is used for Figure 1 A diagram for explaining a method for manufacturing a hollow fiber membrane module is a diagram showing the arrangement of a first molding member and a second molding member in a step of joining the first molding member and the second molding member. Figure 3 It is a partial half-sectional view showing the dimensions of the outer casing of Example 1. Figure 4 This is an external view of the housing of Example 1 which was ruptured by the pressure test. Figure 5 This is an enlarged external view of the outer shell of Example 1 which was ruptured by the pressure test. Figure 6 It is a partial half-sectional view showing the dimensions of the outer casing of the second embodiment. Figure 7 This is an external view of the outer shell of Example 2 after being ruptured by the pressure test. Figure 8 This is an enlarged external view of the outer shell of Example 2 which was ruptured by the pressure test. Fig. 9 It is a partial half-sectional view showing the dimensions of the outer casing of Example 3. Fig.10 This is a first external view of the housing of Example 3 which is ruptured by the pressure test. Fig.11 This is a second external view of the housing of Example 3 which is ruptured by the pressure test. Fig.12 1 is a partial half-sectional view showing the dimensions of the housing case of Comparative Example 1. Fig.13 This is an external view of the outer shell of Comparative Example 1 which was ruptured by the pressure test. Fig.14This is an enlarged external view of the outer shell of Comparative Example 1 which was ruptured by the pressure test. Fig.15 1 is a partial half-sectional view showing the dimensions of the housing case of Comparative Example 2. Fig.16 This is an external view of the outer shell of Comparative Example 2 which was ruptured by the pressure test. Fig.17 This is an enlarged external view of the outer shell of Comparative Example 2 which was ruptured by the pressure test. Fig.18 1 is a partial half-sectional view showing the dimensions of the housing case of Reference Example 1. Fig.19 This is an external view of the housing of Reference Example 1 which was ruptured by the pressure test. Fig. 20 Yes Fig.19 The appearance diagram is observed from other viewing angles after the dotted line portion is enlarged. Fig.21 This is an enlarged external view of the vicinity of the heated joining portion of the second molded member of the housing of Reference Example 1 which was ruptured by the pressure test. Fig. 22 It is a partial half-sectional view showing the dimensions of the housing case of Reference Example 2. Fig.23 This is an external view of the housing of Reference Example 2 which was ruptured by the pressure test. Fig.24 Yes Fig.23 The appearance diagram is observed from other viewing angles after the dotted line portion is enlarged. DETAILED DESCRIPTION

[0010] Hereinafter, a specific embodiment of the present invention (hereinafter referred to as "this embodiment") is described in detail. The following this embodiment is an example for describing the present invention and does not mean that the present invention is limited to the following content. The present invention can be implemented by appropriately modifying it within the scope of its purpose.

[0011] like Figure 1 As shown, the hollow fiber membrane module 10 according to the present embodiment includes: a hollow fiber membrane bundle 11 , a potting material 12 and a module housing 13 .

[0012] The hollow fiber membrane bundle 11 is formed by bundling a plurality of hollow fiber membranes 14. The hollow fiber membranes 14 are porous and filter the fluid passing therethrough.

[0013] In addition, there is no particular restriction on the material of the hollow fiber membrane 14, but polyolefins such as polyvinylidene fluoride, polyethylene and polypropylene, ethylene-vinyl alcohol copolymers, polyamides, polyetherimides, polystyrene, polyvinyl alcohol, polyphenylene ether, polyphenylene sulfide, polysulfone, polyether sulfone, acrylonitrile and acetyl cellulose can be used. Among them, from the aspect of strength performance, crystalline thermoplastic resins such as polyethylene, polypropylene, ethylene-vinyl alcohol copolymers, polyvinyl alcohol and polyvinylidene fluoride with crystallinity can be preferably used. Further preferably, polyolefins, polyvinylidene fluoride, etc. can be used, because they are hydrophobic and thus have high water resistance, and it can be expected that they have durability in ordinary aqueous liquid filtration. Particularly preferably, polyvinylidene fluoride with excellent chemical durability such as chemical resistance can be used. As polyvinylidene fluoride, vinylidene fluoride homopolymers and vinylidene fluoride copolymers with a ratio of 50 mol% and above can be cited. Examples of the vinylidene fluoride copolymer include copolymers of vinylidene fluoride and one or more selected from tetrafluoroethylene, hexafluoropropylene, chlorotrifluoroethylene, or ethylene. As the polyvinylidene fluoride, a vinylidene fluoride homopolymer is most preferred.

[0014] The size of the hollow fiber membrane 14 is not particularly limited, but it is preferred to use a pressure-resistant hollow fiber membrane 14 with an inner diameter of 0.4 to 3 mm, an outer diameter of 0.8 to 6 mm, a membrane thickness of 0.2 to 1.5 mm, a blocking pore size of 0.02 to 1 μm, and an inter-membrane pressure difference of 0.1 to 1.0 MPa.

[0015] The potting material 12 fixes at least a portion of the hollow fiber membrane 14 to the module shell 13. In the present embodiment, the potting material 12 is integrated with both ends of the hollow fiber membrane 14 and fixed to the shell 15 of the module shell 13 described later. In the present embodiment, the potting material 12 is formed by filling the potting material 12 between the outer circumferential surface of the hollow fiber membrane 14 and the inner circumferential surface of the shell 15 and curing it.

[0016] In addition, there is no particular restriction on the material of the potting material 12, but for example, a two-liquid mixed curing resin can be used, preferably a polyurethane resin, an epoxy resin, and a silicone resin. Considering the viscosity, the applicable period, the hardness of the cured product, the mechanical strength, the physical and chemical stability relative to the original solution, the adhesion to the hollow fiber membrane 14, and the adhesion to the component shell 13, it is desirable to appropriately select the potting material 12. For example, from the viewpoint of shortening the manufacturing time and improving the productivity, it is preferred to use a polyurethane resin with a short applicable period. In addition, when there is a requirement for mechanical strength, it is preferred to use an epoxy resin with mechanical durability. In addition, a variety of these resins can also be used in the potting material 12.

[0017] The module case 13 accommodates the hollow fiber membrane bundle 11 . The module case 13 includes an outer shell 15 and two cover members 16 .

[0018] In this embodiment, the outer shell 15 is cylindrical as a whole, and the hollow fiber membrane 14 is accommodated in the inner part of the cylindrical body. The outer shell 15 has an axial total length of more than 1 m. The outer shell 15 has two separate molding members, a first molding member 17 and a second molding member 18.

[0019] The first molded component 17 has an integrally molded cylindrical portion 19 and a nozzle portion 20. The nozzle portion 20 is provided on the side of the cylindrical portion 19 so as to protrude perpendicularly to the axial direction of the cylindrical portion 19. The nozzle portion 20 is provided on the side closer to the second molded component 18 than the potting material 12 in the axial direction of the cylindrical portion 19. The inner cavities of the cylindrical portion 19 and the nozzle portion 20 are connected to each other.

[0020] The nozzle portion 20 functions as a port for passing the fluid between the inside and outside of the first molding member 17. Therefore, the nozzle portion 20 can allow the fluid to flow from the outside into the internal space defined by the inner peripheral surface of the housing shell 15, the outer peripheral surface of each hollow fiber membrane 14, and the exposed surface of the potting material 12, and can also allow the fluid to flow out from the internal space to the outside.

[0021] In addition, the material of the first molding member 17 is not particularly limited, and at least one resin material selected from ABS resin, polyvinyl chloride (PVC), polyphenylene ether (PPE), polypropylene (PP), polysulfone (PSF), polyethersulfone (PES), and polyphenylene sulfide (PPS) can be used. Glass fiber can also be mixed into these resin materials. The first molding member 17 can be manufactured by injection molding, extrusion molding, etc.

[0022] The second molding member 18 is, for example, tubular. The second molding member 18 may also be cylindrical. Both ends of the second molding member 18 in the axial direction are respectively connected to the first molding member 17.

[0023] The wall thickness of the second molded component 18 is substantially constant. The wall thickness of the second molded component 18 may also vary depending on the position in the axial direction. The second molded component 18 may also be a cylinder with an inner diameter of 150 mm or more, preferably a cylinder with an inner diameter of 200 mm or more.

[0024] In addition, the material of the second molding member 18 is not particularly limited, but for example, at least one resin material selected from ABS resin, polyvinyl chloride (PVC), polyphenylene ether (PPE), polypropylene (PP), polysulfone (PSF), polyethersulfone (PES), and polyphenylene sulfide (PPS) can be used. The second molding member 18 can also be molded from the same resin material as the first molding member 17, or a different resin material from each other. Glass fiber can also be mixed into these resin materials. The second molding member 18 can be manufactured by injection molding, extrusion molding, etc.

[0025] The housing case 15 is formed by coaxially and continuously joining the cylindrical portion 19 of the first molding member 17 to both ends of the second molding member 18 in the axial direction. The joining is preferably a joining in which the cylindrical portion 19 of the first molding member 17 and the end faces of the second molding member 18 in the axial direction are butted against each other. The joining is preferably any one of heating, contact heating, and bonding using an organic solvent. Alternatively, the joining may be a joining in which one of the cylindrical portion 19 of the first molding member 17 and the second molding member 18 is inserted into the other.

[0026] The axial joining position of the first molding member 17 and the second molding member 18 is the position of the end faces of the first molding member 17 and the second molding member 18 that are butted against each other in the structure in which the end faces are butted against each other. In the present embodiment, in the structure in which the cylindrical portion 19 of the first molding member 17 and the second molding member 18 are inserted into the other, the joining position is the position closest to the second molding member 18 within the range where the cylindrical portion 19 and the second molding member 18 overlap, as viewed from the direction perpendicular to the axial direction.

[0027] The joining position of the first molded member 17 and the second molded member 18 is the position of the boundary in the axial direction when the boundary between the first molded member 17 and the second molded member 18 can be observed in the cross section of the axis penetrating the housing case 15. When the boundary between the first molded member 17 and the second molded member 18 cannot be observed, the joining position is determined by the method described below.

[0028] The peripheral portion considered as the joining position is cut off at the center side in the longitudinal direction closer to the nozzle portion 20 of the housing shell 15. The cut portion is cut or sliced ​​in the axial direction, and the cross section is magnified and observed to confirm the boundary. In the case where it is difficult to confirm the boundary only by magnified observation, the boundary is confirmed by at least one of magnified observation of the cross section after being colored with ink and magnified observation of the sample collected in a thin film state by transmitting polarized light near the surface of the cross section. In addition, in the case where one of the first molding member 17 and the second molding member 18 is formed by a resin to which a filler such as glass fiber is added, the boundary can be easily and clearly confirmed by using X-ray transmission analysis such as an X-ray microscope. By these methods, when the boundary between the first molding member 17 and the second molding member 18 is confirmed, the position of the boundary in the axial direction is determined as the joining position.

[0029] In the axial direction, the wall thickness of the housing shell 15 at a position which is three times the wall thickness of the second molded component 18 from the bonding position, that is, Figure 1 The wall thickness of the cylindrical portion 19 in the example is 1.0 to 1.3 times the wall thickness of the second molded member 18 at the bonding position. In other words, the value of the wall thickness of the housing case 15 at this position divided by the wall thickness of the second molded member 18 is 1.0 to 1.3.

[0030] In the axial direction, the wall thickness of the housing case 15 at a position 5 times the wall thickness of the second molded member 18 from the later-described joining position, that is, the wall thickness of the cylindrical portion 19 is 1.0 to 1.5 times the wall thickness of the second molded member 18 at the joining position. In other words, the value of the wall thickness of the housing case 15 at this position divided by the wall thickness of the second molded member 18 is 1.0 to 1.5.

[0031] In the present embodiment, the cover member 16 is in a cylindrical or conical shape with one end open. The open ends of the cover member 16 engage with the outer shell 15 at both ends of the outer shell 15 in the axial direction. In the present embodiment, the cover member 16 is fixed to the outer shell 15 by nuts 21. In addition, an O-ring 22 is provided between the cover member 16 and at least one of the potting material 12 and the outer shell 15, and the internal space defined by the cover member 16 and the outer shell 15 is sealed liquid-tightly.

[0032] A duct 23 is provided on the closed end or the thin-diameter side of the tapered portion of the cover member 16. The duct 23 protrudes parallel to the axial direction of the housing case 15. The duct 23 functions as a port for passing a fluid between the inside and the outside of the cover member 16. Therefore, the duct 23 allows a fluid to flow from the outside into the internal space defined by the cover member 16 and the potting material 12, and also allows the fluid to flow out from the internal space to the outside.

[0033] Furthermore, in one example of the present embodiment, both ends of the hollow fiber membrane 14 in the longitudinal direction are exposed in the space defined by the potting material 12 and the cover member 16 .

[0034] In the hollow fiber membrane module 10 having such a structure, for example, the raw liquid flowing into the hollow fiber membrane module 10 from one of the pipes 23 flows to the other pipe 23 through the hollow portion of the hollow fiber membrane 14, and at the same time, a part is filtered by the hollow fiber membrane 14. The filtered filtrate flows into the internal space defined by the inner peripheral surface of the housing shell 15, the outer peripheral surface of the hollow fiber membrane 14, and the exposed surfaces of the two potting materials 12. The filtrate that has flowed into the internal space is discharged from the nozzle portion 20. In addition, the raw liquid that has passed through the hollow portion of the hollow fiber membrane 14 and reached the other pipe 23 is discharged from the other pipe 23 as a concentrated liquid. Alternatively, by allowing the raw liquid to flow into one of the nozzle portions 20 of the hollow fiber membrane module 10, the filtrate is discharged from the pipe 23 and the concentrated liquid is discharged from the other nozzle portion 20.

[0035] Next, the manufacturing method of the hollow fiber membrane module 10 is described. The first molding component 17 and the second molding component 18 are molded by a molding method such as injection molding or extrusion molding. The cylindrical portion 19 of the molded first molding component 17 is placed in a separated state with one end face in the axial direction and the axial end face of the second molding component 18. Figure 2 As shown, a heater 24 is inserted between the two opposing end surfaces es to heat the two end surfaces es.

[0036] After both end surfaces es become molten, the heater 24 is pulled out and the both end surfaces es are butted against each other, thereby joining the first molded member 17 and the second molded member 18. When joining the first molded member 17 and the second molded member 18, the molten end surfaces may be squeezed and expanded from the outer peripheral surface. By joining the first molded member 17 to both ends of the second molded member 18, the outer shell 15 is formed.

[0037] In addition, instead of the heater 24, for example, ultrasonic waves may be applied near the end faces es in a state where the end faces es are butted against each other to heat the cylindrical portion 19 of the first molded member 17 and the end faces es of the second molded member 18. In addition, instead of heating and joining the end faces es, for example, an organic solvent may be used to melt the end faces es to join the end faces es.

[0038] The hollow fiber membranes 14 are bundled into a cylindrical hollow fiber membrane bundle 11 to be inserted into the housing shell 15, thereby maximizing the membrane area, i.e., the filtration area, of each membrane module. A protective net may be further covered on the outer periphery of the hollow fiber membrane bundle 11. The material of the net is not particularly limited, but polyethylene, polypropylene, polyvinyl alcohol, ethylene vinyl acetate copolymer, etc. are preferred.

[0039] It is preferred that both ends of the hollow fiber membrane bundle 11 be plugged in advance to prevent clogging by the potting agent in the subsequent potting step. As a material for plugging, epoxy resin, polyurethane resin, silicone resin, etc. can be used.

[0040] After the stuffed hollow fiber membrane bundle 11 is inserted into the outer shell 15, a potting process is performed in which the two ends of the outer shell 15 are bonded with a potting agent. As bonding methods, there are a centrifugal bonding method and a static bonding method. The centrifugal bonding method is a method of introducing the potting material 12 by using the centrifugal force generated by rotating around the central part of the outer shell 15, and the static bonding method is a method of placing the outer shell 15 vertically and introducing the potting material 12 by using the head difference. The bonding method can be appropriately selected according to the total length of the hollow fiber membrane assembly 10, the diameter of the outer shell 15, the initial viscosity of the mixture of the potting agent used, and the service life. After the potting material 12 is cured, a time for aging at high temperature can also be further set. After the potting material 12 is completely cured, the stuffed part is removed to open the end of the hollow fiber membrane 14.

[0041] The cover member 16 is covered on both ends in the axial direction of the housing case 15 in which the hollow fiber membrane bundle 11 is fixed by the potting material 12. The cover member 16 is fixed to the housing case 15 by nuts 21.

[0042] According to the hollow fiber membrane module 10 constructed as described above, for example, by introducing raw water into the hollow fiber membrane module 10 through the nozzle portion 20, the filtered water filtered through the hollow fiber membrane 14 is discharged from the hollow fiber membrane module 10 through at least one of the pipes 23, and the concentrated water is discharged from the hollow fiber membrane module 10 through the remaining nozzle portion 20 (external pressure filtration).

[0043] In addition, by introducing the raw liquid into the hollow fiber membrane module 10 through any one of the pipes 23, the concentrated water is discharged from the hollow fiber membrane module 10 through the remaining pipe 23, and the filtered water filtered by the hollow fiber membrane 14 is discharged from the hollow fiber membrane module 10 through the two nozzle parts 20 (internal pressure filtration).

[0044] In the hollow fiber membrane module 10 of the present invention, the values ​​of the wall thickness of the outer shell 15 at the position where the distance from the binding position to the first molding member 17 side is 3 times and 5 times the wall thickness of the second molding member 18 divided by the wall thickness of the second molding member 18 are 1.0 to 1.3 and 1.0 to 1.5 respectively. With such a structure, in the hollow fiber membrane module 10, the displacement of the outer shell 15 in the axial direction around the binding position is small relative to the change in wall thickness, so that the rapid change of the stress of the outer shell 15 at the binding position can be alleviated when the interior is pressurized. Therefore, the hollow fiber membrane module 10 suppresses the occurrence of rupture of the outer shell 15 starting from the binding position, and causes the rupture caused by the pressurization of the interior of the outer shell 15 starting from the portion other than the binding position to occur at a higher pressure. In other words, the hollow fiber membrane module 10 has good pressure resistance. For example, in the hollow fiber membrane module 10, the pressure applied to the interior to cause the outer shell 15 to rupture is 2MPa or more. More preferably, in the hollow fiber membrane module 10 , the pressure applied to the inside to rupture the outer casing 15 is 3 MPa or more. Example

[0045] Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

[0046] Hereinafter, the measuring methods and the testing methods used in the examples will be described.

[0047] (Measurement method) In the dimensional measurement of molded parts, digital display vernier calipers of JIS B7507 standard were used for diameter / wall thickness. For the total length, JIS standard vernier calipers of the same specification and special vernier calipers made of stainless steel equal-leg angle steels precisely cut to the specified length were used. Their measured values ​​were measured after being kept in a test room with a temperature adjustment range of 23℃ to 27℃ for more than 48 hours. For the measurement parts, 4 points were measured in a cross shape for diameter and length, and 4 more directions were added for wall thickness, making a total of 8 directions. The simple average number was considered a significant number up to one decimal place.

[0048] (Test method) In both the examples and comparative examples, a housing shell of the desired specification was used, and then, using a stainless steel nut, a stainless steel flange to replace the cover, and an O-ring as auxiliary materials, water was sealed inside, and pressurized from one of the nozzles to confirm the water pressure value that reached the rupture and its rupture location. The pressure increase rate of the water pressure pressurization was set to 0.2 [MPa / sec], and the pressurized water and the surrounding water temperature (pressurized in the water tank) were adjusted to room temperature (23°C-27°C). In addition, in the rupture test, a hydraulic pressure tester manufactured by Yamamoto Hydraulic Industry was used, and a stainless steel water tank (special product) with a top (punched metal) cover was used as a storage tank.

[0049] (Resin used) In Example 1 and Comparative Example 1, ABS resin (Stylac™, AE151 manufactured by Asahi Kasei Corporation) was used as the material of the second molded member, and ABS resin (Stylac™, IM-10 manufactured by Asahi Kasei Corporation) was also used as the material of the first molded member.

[0050] In Examples 2 and 3 and Comparative Example 2, ABS resin (Stylac™, AE15P manufactured by Asahi Kasei Corporation) was used as the material of the second molded member, and ABS resin (Stylac™, IM15P manufactured by Asahi Kasei Corporation) was also used as the material of the first molded member.

[0051] In Reference Examples 1 and 2, polysulfone (manufactured by Solvay, first molding member: Udel P1700, second molding member: Udel P1700) was used for both the first molding member and the second molding member.

[0052] (Example 1) As the second molding component, an ABS resin tube (inner diameter 153 mm, wall thickness 6 mm, length 1800 mm) was prepared. The relationship between the inner diameter and the wall thickness of the second molding component is the standard size of the VU tube of JIS K6741. Figure 3 As the first molded component, two such components were prepared. Figure 3 In the figure, the circle indicated by "R6mm" is a circle with a radius of 6mm, which is the distance of the wall thickness of the second molded component, from the joint position of the first molded component and the second molded component. Figure 3 In the figure, the circle indicated by "R18mm" is a circle with a radius of 18mm, which is three times the wall thickness of the second molded component, from the joint position of the first molded component and the second molded component. Figure 3In the figure, the circle indicated by "R30mm" is a circle having a radius of 30mm, which is five times the wall thickness of the second molded component, from the joining position of the first molded component and the second molded component.

[0053] Through Figure 2 The end surface heating device shown in the figure heats and joins the first molded component and the second molded component to produce the housing shell (total length 2160 mm) of the present invention. Then, pressurization is applied, and as a result, rupture occurs at 3.4 [MPa], with the rupture starting point being approximately the center of the tube, and the rupture shape showing a linear rupture surface in the longitudinal direction (see Figure 4 , Figure 5 ).

[0054] (Example 2) As the second molding component, an ABS resin tube (inner diameter 202 mm, wall thickness 7 mm, length 1640 mm) was prepared. The relationship between the inner diameter and wall thickness of the second molding component was the standard size of the VU tube of JIS K6741. In addition, as the first molding component, two tubes having the following characteristics were prepared: Figure 6 A component having the cross-sectional shape shown (including an illustration of a second molded component). Figure 6 In the figure, the circle indicated by the reference numeral "R7mm" is a circle having a radius of 7 mm, which is the distance equal to the wall thickness of the second molding component, from the joint position of the first molding component and the second molding component. Figure 6 In the figure, the circle indicated by the symbol "R21mm" is a circle with a radius of 21mm, which is three times the wall thickness of the second molded component, from the joint position of the first molded component and the second molded component. Figure 6 In the figure, the circle indicated by "R35mm" is a circle having a radius of 35mm, which is five times the wall thickness of the second molded component, from the joining position of the first molded component and the second molded component.

[0055] Through Figure 2 The end surface heating device shown in the figure heats and joins the first molded component and the second molded component to produce the housing shell (total length 2120 mm) of the present invention. Then, pressurization is applied, and as a result, rupture occurs at 3.1 [MPa], with the rupture starting point being approximately the center of the tube, and the rupture shape showing a serrated rupture surface in the longitudinal direction (see Figure 7 , Figure 8 ).

[0056] (Example 3) As the second molding component, an ABS resin tube (inner diameter 202 mm, wall thickness 7 mm, length 680 mm) was prepared. The relationship between the inner diameter and the wall thickness of the second molding component was the standard size of the VU tube of JIS K6741. In addition, as the first molding component, two Fig. 9A component having the cross-sectional shape shown (including an illustration of a second molded component). Fig. 9 In the figure, the circle indicated by "R7mm" is a circle with a radius of 7mm, which is the distance of the wall thickness of the second molded component, from the joint position of the first molded component and the second molded component. Fig. 9 In the figure, the circle indicated by "R21mm" is a circle with a radius of 21mm, which is three times the wall thickness of the second molded component, from the joint position of the first molded component and the second molded component. Fig. 9 In the figure, the circle indicated by "R35mm" is a circle having a radius of 35mm, which is five times the wall thickness of the second molded component, from the joining position of the first molded component and the second molded component.

[0057] Through Figure 2 The end surface heating device shown in the figure heats and joins the first molded component and the second molded component to produce the housing shell (total length 1160 mm) of the present invention. Then, pressurization was applied, and as a result, rupture occurred at 2.6 [MPa], and the rupture starting point was the threaded portion provided on the outer periphery of the outer end of the first molded component (see Fig.10 , Fig.11 ).

[0058] (Comparative Example 1) As the second molded member, an ABS resin pipe was prepared which was the same as that of Example 1 except that the length was different (1920 mm). Fig.12 The first molded component shown. Fig.12 In the figure, the circle indicated by "R6mm" is a circle with a radius of 6mm, which is the distance of the wall thickness of the second molded component, from the joint position of the first molded component and the second molded component. Fig.12 In the figure, the circle indicated by "R18mm" is a circle with a radius of 18mm, which is three times the wall thickness of the second molded component, from the joint position of the first molded component and the second molded component. Fig.12 In the figure, the circle indicated by "R30mm" is a circle with a radius of 30mm, which is five times the wall thickness of the second molding component, from the joint position of the first molding component and the second molding component. Figure 3The outer shell shell of the illustrated embodiment 1 was produced by joining the second molding component in a state where the second molding component was inserted into the inner cavity of the first molding component. The first molding component and the second molding component were solvent-joined using a doped adhesive of MEK (methyl ethyl ketone) known as a solvent for ABS resin. The doped adhesive is a doped adhesive obtained by dissolving / mixing 30 parts by weight of resin particles used in ABS resin (this time, the first molding component) in MEK. The shell shell was kept in a 35-degree temperature-controlled room with a ventilation device for 7 days to wait for the solvent to evaporate, and then heated at 50 degrees for 48 hours, and then cooled to room temperature to obtain an outer shell shell with a total length of 2160 mm. Pressurization was performed in the same manner as in Example 1. As a result, rupture occurred at 3.0 [MPa], and the starting point of the rupture was the boundary between the first molding component and the second molding component (see Fig.13 , Fig.14 ).

[0059] (Comparative Example 2) As the second molded member, an ABS resin pipe having the same length as that of Example 2 (1800 mm) was prepared. Fig.15 The first molded component shown. Fig.15 In the figure, the circle indicated by "R7mm" is a circle with a radius of 7mm, which is the distance of the wall thickness of the second molded component, from the joint position of the first molded component and the second molded component. Fig.15 In the figure, the circle indicated by "R21mm" is a circle with a radius of 21mm, which is three times the wall thickness of the second molded component, from the joint position of the first molded component and the second molded component. Fig.15 In the figure, the circle indicated by "R35mm" is a circle with a radius of 35mm, which is five times the wall thickness of the second molding component, from the joint position of the first molding component and the second molding component. Figure 6 The outer shell shell of Example 2 shown in the figure was produced by joining the second molding component in a state where the second molding component was inserted into the inner cavity of the first molding component. The first molding component and the second molding component were solvent-joined using a doped adhesive of MEK (methyl ethyl ketone) known as a solvent for ABS resin. The doped adhesive is a doped adhesive obtained by dissolving / mixing 30 parts by weight of resin particles used in ABS resin (this time, the first molding component) in MEK. The shell shell was kept in a 35-degree temperature-controlled room with a ventilation device for 7 days to wait for the solvent to evaporate, and then heated at 50 degrees for 48 hours, and then cooled to room temperature to obtain an outer shell shell with a total length of 2120 mm. Pressurization was performed in the same manner as in Example 2. As a result, rupture occurred at 1.9 [MPa], and the starting point of the rupture was the boundary between the first molding component and the second molding component (see Fig.16 , Fig.17).

[0060] (Reference Example 1) As the second molded component, two polysulfone resin tubes (inner diameter 154 mm, wall thickness 9 mm) were prepared. The relationship between the inner diameter and the wall thickness of the second molded component is the standard size of the VP tube of JIS K6741. Figure 2 The end surface heating device shown in the figure heats and bonds the end surfaces to each other. A clamp is arranged to prevent the molten resin from being exposed at the inner diameter part and the outer diameter part, and heat bonding is performed. As a result, the portion exposed by 1 mm in the radial direction of the inner side / outer side relative to the original inner diameter of the second molded component is as long as 5 mm. The second molded component after heat bonding is cut into 500 mm pieces, and both sides of the second molded component are covered and bonded to the inner cavity of the tubular first molded component having a nozzle part on the side with an epoxy adhesive, and the following is obtained: Fig.18 The housing shell of Reference Example 1 is shown with a total length of 850 mm. Fig.18 In the figure, the circle indicated by "R9mm" is a circle with a radius of 9mm, which is the distance of the wall thickness of the second molding component, from the joint position of the first molding component and the second molding component. Fig.18 In the figure, the circle indicated by "R27mm" is a circle with a radius of 27mm, which is three times the wall thickness of the second molded component, from the joint position of the first molded component and the second molded component. Fig.18 In the figure, the circle indicated by "R45mm" is a circle with a radius of 45mm, which is five times the wall thickness of the second molded component, from the joint position of the first molded component and the second molded component. After wiping off the exposed adhesive, the epoxy adhesive was further accelerated by heating at 40 degrees for 48 hours and at 90 degrees for 20 hours.

[0061] The housing shell of Reference Example 1 manufactured as described above was pressurized, and as a result, it broke at 4.1 [MPa]. In addition, radial cracks centered at the boundary between the second molded component and the first molded component were observed, and the results showed that the boundary portion was the starting point of the crack. It was further confirmed that the heated bonding portion of the second molded components broke on the extension line of the above starting point, not the starting point (see Fig.19 , Fig. 20 , Fig.21 ).

[0062] (Reference Example 2) The same method as in Reference Example 1 was used except that a single tube was used in which the second molded components were not heat-bonded to each other. Fig. 22 The housing shell of Reference Example 2 is shown with a total length of 850 mm. Fig. 22In the figure, the circle indicated by "R9mm" is a circle with a radius of 9mm, which is the distance of the wall thickness of the second molding component, from the joint position of the first molding component and the second molding component. Fig. 22 In the figure, the circle indicated by "R27mm" is a circle with a radius of 27mm, which is three times the wall thickness of the second molded component, from the joint position of the first molded component and the second molded component. Fig. 22 In the figure, the circle indicated by "R45mm" is a circle with a radius of 45mm, which is five times the wall thickness of the second molded member, from the joint position of the first molded member and the second molded member. The housing shell of Reference Example 2 was pressurized, and as a result, it broke at 3.8 [MPa]. Similar to Reference Example 1, radial cracks centered on the boundary between the second molded member and the first molded member were observed, and the results showed that the boundary portion was the starting point of the crack (see Fig.23 , Fig.24 ).

[0063] Table 1 summarizes the dimensions and results of various members used in the above-mentioned examples, comparative examples, and reference examples.

[0064] [Table 1] Description of symbols

[0065] 10 Hollow fiber membrane module 11 Hollow fiber membrane bundle 12 Potting materials 13 Component housing 14 Hollow fiber membrane 15 Shell 16 Cover member 17 First molding component 18 Second molding component 19 cylindrical part 20 Nozzle section 21 Nut 22 O-ring 23 Pipe 24 Heater es end face

Claims

1. A hollow fiber membrane module, characterized in that: include: A hollow fiber membrane bundle, wherein the hollow fiber membrane bundle is formed by bundling a plurality of hollow fiber membranes; as well as The outer shell has a first molding component and a second molding component, and accommodates the hollow fiber membrane bundle, the first molding component is integrally formed by a cylindrical part and a nozzle part whose inner cavity is connected to the cylindrical part, and the second molding component is a cylindrical shape that is coaxial and continuous with the cylindrical part, The total length of the housing in the axial direction exceeds 1 m. In the axial direction, the values ​​of the wall thickness of the outer shell shell divided by the wall thickness of the second molding member at positions where the distances from the combination position of the first molding member and the second molding member to the first molding member side are 3 times and 5 times the wall thickness of the second molding member, respectively, are 1.0 to 1.3 and 1.0 to 1.5, respectively.

2. The hollow fiber membrane assembly according to claim 1, characterized in that: The second molding member is in a cylindrical shape with an inner diameter of 150 mm or more.

3. The hollow fiber membrane assembly according to claim 2, characterized in that: The second molding member is cylindrical with an inner diameter of 200 mm or more.

4. The hollow fiber membrane module according to any one of claims 1 to 3, characterized in that: The portion other than the joining position is ruptured by pressurization of the interior of the outer shell case.

5. The hollow fiber membrane module according to any one of claims 1 to 4, characterized in that: The first molded member and the second molded member are molded of at least one resin material selected from ABS resin, polyvinyl chloride, polyphenylene ether, polypropylene, polysulfone, polyethersulfone, and polyphenylene sulfide.

6. The hollow fiber membrane module according to any one of claims 1 to 5, characterized in that: The first molded member and the second molded member are molded from the same resin material.

7. The hollow fiber membrane module according to any one of claims 1 to 6, characterized in that: At least one of the first molding member and the second molding member is molded from a resin material mixed with glass fibers.

8. A method for manufacturing a hollow fiber membrane module according to any one of claims 1 to 7, characterized in that: include: The housing case is formed by abutting and joining the first molded member and the second molded member.

9. The manufacturing method according to claim 8, characterized in that: include: The first molding member and the second molding member are bonded by any one of heating, contact heating, and an organic solvent.

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