Separation membrane module and method for manufacturing the same

Abstract

A separation membrane module and a method for manufacturing the same are provided. A separation membrane module according to one embodiment of the present invention includes an outflow pipe, a cylindrical filter assembly, and a wrapping portion in which composite fibers containing inorganic fibers and a polymer resin are wound so as to enclose the outer surface of the filter assembly, wherein at least a portion of the wrapping portion is bonded through the polymer resin between adjacent composite fibers. According to the present invention, a separation membrane module and a method for manufacturing the same can achieve the effects of a low defect rate, excellent high-pressure resistance, elimination of the risk of accidents to workers due to process automation, and the ability to perform low-temperature processes while simultaneously reducing process time and costs.

Description

[Technical Field]

[0001] The present invention relates to a separation membrane module, and more particularly to a separation membrane module and a method for manufacturing the same, which has a low defect rate, excellent high-pressure resistance, eliminates the risk of worker accidents through process automation, enables low-temperature processes, and simultaneously reduces process time and cost. [Background technology]

[0002] Separation membranes are classified according to pore size into microfiltration membranes (MF), ultrafiltration membranes (UF), nanoseparation membranes (NF), and reverse osmosis membranes (RO).

[0003] To apply such separation membranes to industrial-scale liquid separation, a very large membrane area is required. A device unit that integrates a large membrane area in a compact size is called a separation membrane module, and currently, various types of membrane modules have been developed, such as plate modules, tubular modules, hollow fiber modules, and spiral-wound modules. In particular, spiral-wound modules are mainly used in the permeable membrane modules that have been commercialized recently.

[0004] In the spiral-wound module, the wrapping process involves winding a predetermined fiber onto the outer surface. Conventionally, this wrapping process involved spraying a mixture of epoxy resin and hardener while winding the fiber. However, this method suffered from frequent scattering of the epoxy resin and hardener, leading to curing failures and an increased defect rate. Furthermore, the extremely long curing time resulted in excessively long process times. Additionally, the use of a mixed epoxy resin and hardener solution made disposal after use highly environmentally unfriendly. Moreover, the wet wrapping process necessitated squeegeeing to treat the resin flowing onto the surface during the process. This squeegeeing process required human intervention, making automation difficult and increasing the risk of worker accidents. Finally, despite the impossibility of low-temperature processing, the process time was long and the cost was high. [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] The present invention has been made in consideration of the above-mentioned points, and aims to provide a separation membrane module and a method for manufacturing the same that have a low defect rate, excellent high-pressure durability, eliminate the risk of accidents to workers through process automation, enable low-temperature processes, and simultaneously reduce process time and cost. [Means for solving the problem]

[0006] To solve the aforementioned problems, the present invention provides a separation membrane module comprising an outflow pipe, a cylindrical filter assembly arranged to surround the outside of the outflow pipe, and a wrapping portion in which composite fibers containing inorganic fibers and polymer resin are wound to enclose the outer surface of the filter assembly, wherein at least a portion of the wrapping portion is bonded through polymer resin between adjacent composite fibers.

[0007] According to one embodiment of the present invention, the composite fiber may be a sheath-core type composite fiber including a core portion and a sheath portion, wherein the core portion may contain inorganic fibers and the sheath portion may contain a polymer resin.

[0008] Furthermore, the inorganic fiber may contain one or more of the following: glass fiber, carbon fiber, and metal fiber.

[0009] Furthermore, the polymer resin may also include a UV-curable resin.

[0010] Furthermore, the polymer resin may include one or more selected from the group consisting of epoxy acrylate, urethane acrylate, polyester acrylate, polyether acrylate, and polyacrylic acrylate.

[0011] Furthermore, the composite fiber may contain 10 to 70 parts by weight of the polymer resin per 100 parts by weight of the inorganic fiber.

[0012] Furthermore, the filter assembly may be wound in a spiral shape on the outflow pipe.

[0013] The filter assembly may also include a separation membrane that is bent to form at least one leaf, an internal spacer positioned inside the leaf, and an external spacer positioned outside the leaf.

[0014] Furthermore, the internal spacer may include a mesh sheet, and the external spacer may include a tricot filtration channel.

[0015] Furthermore, the present invention provides a method for manufacturing a separation membrane module, comprising the steps of: winding temporary composite fibers, manufactured by impregnating inorganic fibers with a polymer resin composition containing a polymer resin, onto the outer surface of an outflow pipe and a cylindrical filter assembly arranged to surround the outside of the outflow pipe; and curing the polymer resin of the temporary composite fibers to form a wrapping portion such that at least a portion is bonded through the polymer resin between adjacent composite fibers.

[0016] According to one embodiment of the present invention, the composite fiber may contain 10 to 70 parts by weight of the polymer resin per 100 parts by weight of the inorganic fiber.

[0017] Furthermore, the polymer resin may also include a UV-curable resin, and the curing during the stage of forming the wrapping portion is performed with a UV irradiation dose of 1,300 to 1,500 mJ / cm². 2 It can be done under these conditions. [Effects of the Invention]

[0018] According to the present invention, the separation membrane module and its manufacturing method have a low defect rate, excellent high-pressure resistance, eliminate the risk of accidents to workers through process automation, enable low-temperature processes, and simultaneously reduce process time and costs. [Brief explanation of the drawing]

[0019] [Figure 1] Figure 1 is a perspective view of a separation membrane module according to an embodiment of the present invention. [Figure 2] Figure 2 is a schematic cross-sectional view of an outflow pipe and a filter assembly provided in a separation membrane module according to an embodiment of the present invention.

Best Mode for Carrying Out the Invention

[0020] Hereinafter, referring to the accompanying drawings, embodiments of the present invention will be described in detail so that those having ordinary knowledge in the technical field to which the present invention pertains can easily implement it. The present invention can be embodied in various different forms and is not limited to the embodiments described herein. In the drawings, parts not related to the description are omitted in order to clearly explain the present invention, and the same reference numerals are given to the same or similar components throughout the specification.

[0021] As shown in FIG. 1, the separation membrane module 1000 according to the present invention includes an outflow pipe 100, a cylindrical filter assembly 200 disposed so as to surround the outside of the outflow pipe, and a wrapping portion 300 in which composite fibers containing inorganic fibers and a polymer resin are wound so as to wrap the outer surface of the filter assembly 200. The wrapping portion 300 is embodied such that at least a part thereof is bonded through the polymer resin between adjacent composite fibers.

[0022] Hereinafter, each component included in the separation membrane module 1000 of the present invention will be described.

[0023] First, the outflow pipe 100 will be described.

[0024] The outflow pipe 100 may be composed of a hollow pipe member having openings at one or both ends thereof and including at least one or more holes through which product water flows in.

[0025] The aforementioned outflow pipe can be any known outflow pipe applicable to the separation membrane module, and therefore, the present invention does not particularly limit it.

[0026] Next, the filter assembly 200 will be described.

[0027] The filter assembly 200 may be a cylindrical filter assembly arranged to surround the outside of the outflow pipe, and preferably, as shown in Figure 2, it may be wound spirally on the outflow pipe 100.

[0028] When the filter assembly is wound in a spiral shape, the filter assembly 200 may include a separation membrane 210 that is bent to form at least one leaf, an internal spacer 220 positioned inside the leaf, and an external spacer 230 positioned outside the leaf.

[0029] The raw water treatment process using the separation membrane module 1000 is as follows: Inflow water passes through the internal spacer 220 and then through the separation membrane 210. As it passes through the separation membrane 210, dissolved salts and organic matter are removed, and pure water is separated. The separated water flows along the external spacer 230, and this separated water collects in the central outlet pipe 100 and is discharged outside the separation membrane module 1000.

[0030] The separation membrane 210 can be any separation membrane that is commonly applicable to separation membrane modules in the industry, and therefore, the present invention does not particularly limit it.

[0031] Furthermore, the internal spacer 220 plays a role in forming a flow path inside the leaf. Specifically, by positioning the internal spacer 220 inside the leaf formed by bending the separation membrane 210, the formation of a flow path inside the leaf as a feed channel can be greatly improved.

[0032] The internal spacer 220 can be any internal spacer that is commonly applicable to separation membrane modules in the industry, and preferably includes a mesh sheet.

[0033] The aforementioned mesh sheet can be used without limitation as an internal spacer for a filter assembly, and preferably, polypropylene, polyethylene, or a polyolefin copolymer in which polypropylene and polyethylene are mixed in a certain ratio can be used as the material for the mesh sheet.

[0034] The internal spacer 220 has an average gap of 6 mm in order to facilitate the formation of the flow path. 2 ~20mm 2 Preferably, 9 mm 2 ~17mm 2 It is possible. The gap is 6 mm. 2 If it is less than 20mm, there may be problems that hinder the formation of the flow path. 2 If the pressure exceeds a certain level, there may be issues where high-pressure operation can reduce deformation and fouling of the separation membrane.

[0035] Furthermore, the average thickness of the internal spacer 220 may be 0.2 mm to 3 mm, preferably 0.2 mm to 2.0 mm. If the average thickness of the internal spacer 220 is less than 0.2 mm, sufficient flow path cannot be secured, and if it exceeds 3 mm, it may reduce the effective film area per unit volume, affecting the degradation of module performance.

[0036] The external spacer 230 is positioned on the outside of the reef and plays a role in forming a flow path outside the reef. Specifically, the external spacer 230 is positioned on the outside of the reef, and if there are two or more reefs, it is positioned between the reefs, thereby functioning as a permeate spacer.

[0037] The external spacer 230 can be any external spacer that is commonly applicable to separation membrane modules in the industry, and preferably includes a tricot filtration channel.

[0038] The tricot filtration channel can be used without limitation in the case of tricot that can be used as an external spacer for the filter assembly, and is preferably formed from one or more resins selected from the group consisting of polypropylene, polyethylene, poly-4-methylpentene, propylene-α-olefin crystalline copolymer, polyethylene terephthalate, polybutylene terephthalate, polyamide, and polycarbonate, or from a low-melting polyethylene terephthalate (LMP) modified by copolymerizing a polyethylene terephthalate resin with nylon, polypropylene, or epoxy resin.

[0039] Next, the wrapping section 300 will be described.

[0040] As described above, the wrapping portion 300 is formed by winding composite fibers containing inorganic fibers and polymer resin so as to wrap the outer surface of the filter assembly 200, and the wrapping portion 300 is embodied such that at least a portion of it is bonded through the polymer resin between adjacent composite fibers.

[0041] The composite fiber may be one or more of a sheath-core type composite fiber including a core portion and a sheath portion, or a side-by-side type composite fiber, but preferably it is a sheath-core type composite fiber including a core portion and a sheath portion, which is more preferable from the viewpoint that at least a portion is bonded through the polymer resin between adjacent composite fibers.

[0042] Furthermore, the sheath-core type composite fiber may be a concentric sheath-core type composite fiber in which the centers of the core portion and the sheath portion are the same, or an eccentric sheath-core type composite fiber in which the centers of the core portion and the sheath portion are different, but the present invention does not particularly limit this.

[0043] In this case, the sheath-core type composite fiber may contain inorganic fibers in the core portion and a polymer resin in the sheath portion.

[0044] The inorganic fibers can be any inorganic fibers that are commonly used in the industry, and preferably include one or more of glass fibers, carbon fibers, and metal fibers. More preferably, including glass fibers may be even more advantageous in achieving the objectives of the present invention.

[0045] Furthermore, the inorganic fiber may be a monofilament or a multifilament formed of fiber bundles. If the inorganic fiber is a multifilament, the multifilament may contain one of the glass fiber, carbon fiber, and metal fiber alone, or it may contain two or more of the glass fiber, carbon fiber, and metal fiber in combination.

[0046] Furthermore, the polymer resin can be any polymer resin that is commonly used in the industry, and preferably, including a UV-curable resin may be even more advantageous in achieving the objectives of the present invention. The UV-curable resin may preferably include one or more selected from the group consisting of epoxy acrylates, urethane acrylates, polyester acrylates, polyether acrylates, and polyacrylic acrylates, which may be even more advantageous in achieving the objectives of the present invention.

[0047] In this case, the UV-curable resin may further contain a UV initiator, and any known UV initiator can be used without limitation; therefore, the present invention does not particularly limit it. The UV initiator may be included in an amount of 0.5 to 7 parts by weight, preferably 1 to 6 parts by weight, per 100 parts by weight of the UV-curable resin. It may be even more advantageous for achieving the objectives of the present invention if the UV initiator satisfies the above content.

[0048] Furthermore, the composite fiber can be formed by twisting a fiber containing the polymer resin onto the inorganic fiber, or by impregnating or coating the inorganic fiber with a polymer resin composition so that the polymer resin is arranged on its surface. Preferably, forming the composite fiber by impregnating the inorganic fiber with a polymer resin composition so that the polymer resin is arranged on its surface may be even more advantageous in achieving the objectives of the present invention.

[0049] Furthermore, the composite fiber may contain 10 to 70 parts by weight, preferably 15 to 65 parts by weight, of the polymer resin per 100 parts by weight of the inorganic fiber. If the polymer resin is less than 10 parts by weight per 100 parts by weight of the inorganic fiber, the composite fiber may not be fixed to the outer surface of the filter assembly, which may lead to defects and a decrease in the durability of the separation membrane module. If the polymer resin is more than 70 parts by weight per 100 parts by weight of the inorganic fiber, the durability of the separation membrane module may decrease, which may lead to defects under high-pressure conditions.

[0050] The separation membrane module according to the present invention is manufactured by a manufacturing method that includes the steps of winding temporary composite fibers, which are produced by impregnating inorganic fibers with a polymer resin composition containing a polymer resin, onto the outer surface of an outflow pipe and a cylindrical filter assembly arranged to surround the outside of the outflow pipe, and curing the polymer resin of the temporary composite fibers to form a wrapping portion such that at least a portion is bonded through the polymer resin between adjacent composite fibers.

[0051] In the description of the manufacturing method of the separation membrane module, the same explanations regarding each component described in the above-mentioned separation membrane module will be omitted.

[0052] As mentioned above, the polymer resin includes a UV-curable resin, so that the curing of the polymer resin can be performed by UV irradiation during the stage of forming the wrapping portion.

[0053] In this case, the curing is performed with a UV irradiation dose of 1,300 to 1,500 mJ / cm².2 Under the conditions of, preferably, 1,330 to 1,470 mJ / cm 2 it can be carried out. When the UV irradiation amount is less than 1,300 mJ / cm 2 , the UV-curable resin may not be cured at the target level. When the UV irradiation amount exceeds 1,500 mJ / cm 2 , the process time becomes long, a discoloration phenomenon due to over-curing occurs, and the result of deterioration of physical properties can appear.

[0054] According to the present invention, the separation membrane module and its manufacturing method have a low defect rate, excellent high-pressure durability, eliminate the accident risk of workers due to process automation, enable a low-temperature process, and at the same time can shorten the process time and cost.

Mode for Carrying Out the Invention

[0055] The present invention will be described more specifically based on the following examples, but the following examples do not limit the scope of the present invention, and this should be understood as for helping the understanding of the present invention.

[0056] [Examples] [Example 1] First, a separation membrane in which a membrane (polyamide membrane) is sequentially laminated in a stepped structure with a step interval of about 5 mm on an 8-inch outflow pipe is bent, and 24 leaves are formed so that a mesh sheet of a polyethylene and polypropylene composite material as an internal spacer is arranged inside the separation membrane. A spiral wound module in which a filter assembly formed so that a tricot as an external spacer is arranged in the region between the formed leaves is rolled in the structure shown in FIG. 2 was manufactured.

[0057] Next, glass fibers (OWENS CORNING KOREA, SE4540-2200TEX) as inorganic fibers were impregnated with a polymer resin composition prepared by mixing 100 parts by weight of epoxy acrylate resin (KUKDO Chemical, DP-75) as a UV-curable resin with 3 parts by weight of radical initiator (IGM RESINS, Omnirad 1173) at 50°C for 2 hours using a blade with adjustable gap at a temperature of 50°C to produce a provisional composite fiber.

[0058] Subsequently, the temporary composite fibers were wound around the spiral-wound module so that they wrapped around the outer surface of the filter assembly in the longitudinal direction of the outflow tube, under conditions of a transfer speed of the spiral-wound module (in the longitudinal direction of the outflow tube) of 1,400 mm / min and a rotation speed of the spiral-wound module of 120 revolutions / min. UV light was then irradiated at a distance of 35 mm from the UV lamp for 27 seconds, resulting in a UV irradiation dose of 1,463 mJ / cm². 2 A separation membrane module was manufactured by curing a UV-curable resin under the specified conditions, and including a wrapping portion in which composite fibers containing inorganic fibers and polymer resin were wound to enclose the outer surface of the filter assembly. In this case, the polymer resin was 53.8 parts by weight per 100 parts by weight of inorganic fibers, and the composite fibers were formed as sheath-core type composite fibers, with inorganic fibers in the core portion and polymer resin in the sheath portion.

[0059] <Examples 2-8 and Comparative Example 1> The separation membrane modules shown in Tables 1 and 2 were manufactured by following the same procedure as in Example 1, but with changes to the polymer resin content, UV irradiation amount, and whether or not the wrapping portion was included.

[0060] <Comparative Example 2> The separation membrane module was manufactured in the same manner as in Example 1, but instead of composite fibers, glass fibers that had come into contact with a mixture of epoxy resin and a curing agent were wound onto a spiral-wound module so as to wrap around the outer surface of the filter assembly in the longitudinal direction of the outflow pipe, and cured in a curing room at 38°C for 10 hours.

[0061] <Comparative Example 3> The separation membrane module was manufactured in the same manner as in Comparative Example 2, but cured in a 60°C curing room for 27 seconds.

[0062] <Example of experiment> The following items were evaluated for the separation membrane modules manufactured in the examples and comparative examples, and the results are shown in Tables 1 and 2 below.

[0063] 1. Evaluation of the defect rate The defect rates of the separation membrane modules produced in the examples and comparative examples were evaluated. Specifically, the defect rates of the separation membrane modules produced in the examples and comparative examples were evaluated visually and tactilely by 15 individuals with more than 10 years of experience in the relevant field. In this process, the average score was calculated on a 10-point scale, and the defect rate was evaluated as follows: 8 points or higher was marked "○", 4 points or higher but less than 8 points was marked "△", and less than 4 points was marked "×".

[0064] 2. Evaluation of high-pressure durability High-pressure durability was evaluated by assigning a "○" if there were no problems when operating under a pressure of 600 psi, and a "×" if any problems occurred, such as channeling where internal components protrude.

[0065] [Table 1]

[0066] [Table 2]

[0067] As can be seen from Tables 1 and 2 above, Examples 1, 3, 4, and 7, which satisfy all of the following conditions according to the present invention, such as the polymer resin content, UV irradiation amount, presence or absence of wrapping portion, type of polymer resin, curing method, and time, have significantly lower defect rates, significantly superior high-pressure durability, and significantly shorter process times compared to Examples 2, 5, 6, 8 and Comparative Examples 1-3, which do not satisfy even one of these conditions.

[0068] Although one embodiment of the present invention has been described above, the concept of the present invention is not limited to the embodiments presented herein. Those skilled in the art who understand the concept of the present invention can easily propose other embodiments within the same scope of the invention by adding, changing, deleting, or adding components, and these are also understood to be within the scope of the present invention.

[0069] [Explanation of symbols] 100 Outflow pipe 200 filter assembly 210 Separation membrane 220 Internal Spacer 230 External Spacer 300 Wrapping Department 1000 Separation Membrane Modules

Claims

1. Outlet pipe and A cylindrical filter assembly is arranged to surround the outside of the aforementioned outflow pipe, The filter assembly includes a wrapping portion in which composite fibers containing inorganic fibers and polymer resin are wound so as to enclose the outer surface of the filter assembly, The wrapping portion is a separation membrane module in which at least a portion is bonded through a polymer resin between adjacent composite fibers.

2. The aforementioned composite fiber is a sheath-core type composite fiber including a core portion and a sheath portion. The separation membrane module according to claim 1, wherein the core portion contains inorganic fibers and the sheath portion contains a polymer resin.

3. The separation membrane module according to claim 1, wherein the inorganic fiber comprises one or more of glass fibers, carbon fibers, and metal fibers.

4. The separation membrane module according to claim 1, wherein the polymer resin includes a UV-curable resin.

5. The separation membrane module according to claim 1, wherein the polymer resin comprises one or more selected from the group consisting of epoxy acrylate, urethane acrylate, polyester acrylate, polyether acrylate, and polyacrylic acrylate.

6. The separation membrane module according to claim 1, wherein the composite fiber comprises 10 to 70 parts by weight of the polymer resin per 100 parts by weight of the inorganic fiber.

7. The separation membrane module according to claim 1, wherein the filter assembly is wound spirally on the outflow pipe.

8. The aforementioned filter assembly is A separation membrane provided by being folded to form at least one leaf, An internal spacer positioned inside the leaf, The separation membrane module according to claim 7, further comprising an external spacer disposed on the outside of the leaf.

9. The aforementioned internal spacer includes a mesh sheet, The separation membrane module according to claim 8, wherein the external spacer includes a tricot filtration channel.

10. The process involves winding a temporary composite fiber, manufactured by impregnating inorganic fibers with a polymer resin composition containing a polymer resin, onto the outer surface of the outflow pipe and a cylindrical filter assembly arranged to surround the outside of the outflow pipe, A method for manufacturing a separation membrane module, comprising the step of curing the polymer resin of the temporary composite fibers to form a wrapping portion such that at least a portion of it is bonded through the polymer resin between adjacent composite fibers.

11. The method for manufacturing a separation membrane module according to claim 10, wherein the composite fiber comprises 10 to 70 parts by weight of the polymer resin per 100 parts by weight of the inorganic fiber.

12. The aforementioned polymer resin includes a UV-curing resin. In the step of forming the wrapping portion, the curing is performed with a UV irradiation dose of 1,300 to 1,500 mJ / cm². ２ A method for manufacturing a separation membrane module according to claim 10, carried out under the following conditions.

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