JP2011072900A - Hollow fiber membrane module, method for manufacturing hollow fiber membrane module, cartridge for water purifier, and water purifier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hollow fiber membrane module of higher filtration capacity and a cartridge for a water purifier having a hollow fiber membrane module by easily removing a sheet wrapping a hollow fiber membrane bundle, thereby maintaining a sufficient membrane area of a hydrophilic hollow fiber membrane even if a hydrophobic hollow fiber membrane is incorporated into the module as a countermeasure to filtration flow rate deterioration at a low water pressure. <P>SOLUTION: There is provided the hollow fiber membrane module configured such that a hollow fiber membrane bundle is filled up in a U-shaped form in a cylindrical case with the opened end of the hollow fiber membrane bundle fixed to the opened section of the cylindrical case with a potting material, wherein the hollow fiber membrane bundle is one where a hydrophobic hollow fiber membrane is mixed with a hydrophilic hollow fiber membrane, the hollow fiber membrane bundle is disposed in unrestrained state, and the hollow fiber membranes at the outermost circumference of the hollow fiber membrane bundle are all the hydrophilic hollow fiber membranes on the cylindrical case end of the module. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hollow fiber membrane module, a method for producing a hollow fiber membrane module, a water purifier cartridge, and a water purifier.

  Conventionally, many cartridges of water purifiers are composed of modules filled with granular, fibrous or spherical adsorbents such as activated carbon and ion exchangers and hollow fiber membranes. As the material for the hollow fiber membrane, polyethylene, polysulfone, and the like are known, but these polymers are all hydrophobic and hardly pass water in this state. When a membrane is used as a water purifier application, hydrophilic treatment is required. For the hydrophilization treatment, a method of hydrophilizing with a solvent such as alcohol after film formation, a method of imparting hydrophilicity by discharging an injection solution containing a hydrophilic polymer together with a film-forming stock solution from a double annular die, etc. There is. By performing such a hydrophilic treatment, water permeability is increased.

  However, on the other hand, if a module consisting only of a hydrophilic hollow fiber membrane is used, the air permeability decreases. That is, in the case of a water purifier having a module consisting only of a hydrophilic hollow fiber membrane, if air enters the module from the tap water inlet side of the water purifier for some reason, it is mixed especially at low water pressure (eg, 0.1 MPa or less). Air hardly passes through the hydrophilic hollow fiber membrane. In some cases, air stays in the upstream side of the module and becomes resistance, preventing water from passing therethrough and reducing the filtration flow rate.

  In order to solve such a problem, Patent Document 1 discloses a method of discharging the air upstream of the module by keeping all of the membrane hydrophilic rather than making all of the membrane hydrophilic. It is disclosed. However, since this method consumes a large amount of a solvent such as alcohol, measures for ventilation and waste liquid treatment are required, and there is a problem that equipment costs are increased.

  Patent Document 2 discloses a method for discharging air accumulated in a module out of the system by mixing a hydrophobic hollow fiber membrane with a part of the module made of a hydrophilic hollow fiber membrane. However, there is no disclosure at all regarding a manufacturing method such as how to mix hydrophilic hollow fiber membranes and hydrophobic hollow fiber membranes and how to modularize them.

  As a method for manufacturing the module, there is a method in which a hollow fiber membrane bundle having a U-shape is covered with a sheet so as not to expand and loaded into a cylindrical case. However, according to the knowledge of the present inventors, when a sheet is included in the module as shown in FIG. 1, the hollow fiber membrane bundle is densely bound by the sheet, and the flow of water in the module tends to deteriorate. Thus, the hollow fiber membrane is not effectively used, and the turbid filtration ability is reduced. According to the knowledge of the present inventors, it is preferable to remove the sheet covering the hollow fiber membrane bundle in the course of manufacturing the module as shown in FIG. 2 to make the hollow fiber membrane bundle unrestrained, as shown in FIG. A manufacturing method such as Patent Document 3 in which the sheet is removed while gripping the hollow fiber membrane bundle opening loaded in the case is preferable from the viewpoint of improving the performance of the hollow fiber membrane module.

Japanese Patent Laid-Open No. 10-28852 Japanese Patent No. 2720364 Japanese Patent No. 3223993

  However, when the hollow fiber membrane bundle is a mixture of a hydrophilic hollow fiber membrane and a hydrophobic hollow fiber membrane, the hydrophobic hollow fiber membrane is sometimes arranged outside the hollow fiber membrane bundle as shown in FIG. In this case, according to the knowledge of the present inventors, in the conventional technique as described above for removing the sheet, the hydrophobic hollow fiber membrane is stronger than the hydrophilic hollow fiber membrane, and the hollow fiber membrane bundle is formed into a U-shape. Since the force for restoring the straight shape only to the hydrophobic hollow fiber membrane after forming the shape, only the hydrophobic hollow fiber membrane may be detached from the gripping portion at the open end of the hollow fiber membrane bundle. Further, since the friction between the hydrophobic hollow fiber membrane and the sheet is larger than that of the hydrophilic hollow fiber membrane, the sheet is removed and only the hydrophobic hollow fiber membrane is lifted out of the cylindrical case as shown in FIG. There was a problem.

  The present invention can easily remove the sheet that wraps the hollow fiber membrane bundle and does not allow the hollow fiber membrane bundle to be concentrated in an unconstrained state. A hollow fiber membrane module and a hollow fiber membrane module that have a high filtration capacity by allowing dirt on the surface of the hollow fiber membrane to be easily removed by rubbing between them, and that can discharge air staying upstream of the module to the outside of the system. An object is to provide a cartridge for a water purifier installed.

In order to solve the above problem, the present invention includes the following (1) to (8).
(1) A hollow fiber membrane module in which a hollow fiber membrane bundle is filled in a U-shape in a cylindrical case, and an opening end of the hollow fiber membrane bundle is fixed to an opening of the cylindrical case with a potting material, The hollow fiber membrane bundle is a mixture of a hydrophilic hollow fiber membrane and a hydrophobic hollow fiber membrane, and the hollow fiber membrane bundle is housed in the cylindrical case in an unconstrained state, and at the end surface of the cylindrical case A hollow fiber membrane module, wherein all of the hollow fiber membranes on the outermost periphery of the hollow fiber membrane bundle are the hydrophilic hollow fiber membranes.
(2) When the inner radius of the cylindrical case is r, the position of the end of the hydrophobic hollow fiber membrane is 0.9r from the center of the circle of the cylindrical case on the end surface of the cylindrical case. The hollow fiber membrane module according to (1), which is disposed in a drawn circumferential region.
(3) A hollow fiber membrane module in which a hollow fiber membrane bundle is filled in a U-shape in a cylindrical case, and an opening end of the hollow fiber membrane bundle is fixed to an opening of the cylindrical case with a potting material, The hollow fiber membrane bundle is a mixture of a hydrophilic hollow fiber membrane and a hydrophobic hollow fiber membrane, and the hollow fiber membrane bundle is housed in the cylindrical case in an unconstrained state, and the side surface of the hollow fiber membrane module The hollow fiber membrane module is characterized in that the length of the portion where the hydrophobic hollow fiber membrane is located on the outermost periphery of the bundle of hollow fiber membranes is 25% or less of the length of the cylindrical case.
(4) The ratio of the membrane area of the hydrophobic hollow fiber membrane is 0.05 to 5% with respect to the hydrophilic hollow fiber membrane, according to any one of (1) to (3), Hollow fiber membrane module.
(5) After making the hollow fiber membrane bundle into a U shape, the hollow fiber membrane bundle is covered with a sheet all around, filled into a cylindrical case in a state of being wrapped in the sheet, and then the hollow fiber membrane bundle is made of a potting material. A method of manufacturing a hollow fiber membrane module in which an open end is fixed to an opening of the cylindrical case, wherein the hollow fiber membrane bundle includes a hydrophilic hollow fiber membrane and a hydrophobic hollow fiber membrane. A hollow fiber membrane is wrapped inside the hydrophilic hollow fiber membrane to form a hollow fiber membrane bundle, which is then U-shaped, and after the hollow fiber membrane bundle is filled in the cylindrical case, the sheet is removed. Manufacturing method of hollow fiber membrane module.
(6) A water purifier cartridge equipped with the hollow fiber membrane module according to any one of (1) to (4).
(7) A water purifier equipped with the hollow fiber membrane module according to any one of (1) to (4).
(8) A water purifier equipped with the water purifier cartridge according to (6).

  In the present invention, the “open end of the hollow fiber membrane bundle” refers to the end of the hollow fiber membrane that is open.

In the present invention, the “inner radius r of the cylindrical case” is defined separately in the following two cases.
a) When the inner diameter of the cylindrical case at the hollow fiber membrane bundle body is greater than or equal to the inner diameter of the cylindrical case end surface, r is the inner radius of the cylindrical case end surface, and b) When the inner diameter of the cylindrical case is smaller than the inner diameter of the end face of the cylindrical case, the inner radius of the cylindrical case in the hollow fiber membrane bundle body is defined as r. Here, the hollow fiber membrane bundle body portion refers to a straight portion of a U-shaped hollow fiber membrane bundle, and the inner diameter of the cylindrical case in the hollow fiber membrane bundle body portion is a U-shaped hollow fiber membrane. It refers to the smallest inner diameter of the cylindrical case in the straight portion of the bundle.

  Details will be described with reference to the drawings. a) When the inner diameter of the cylindrical case in the hollow fiber membrane bundle body as shown in FIGS. 2 and 6 is larger than or equal to the inner diameter of the cylindrical case end face, the inner radius of the case end face is set to the inner diameter of the cylindrical case. B) When the inner diameter of the cylindrical case in the hollow fiber membrane bundle body portion is smaller than the inner diameter of the end surface of the cylindrical case, as shown in FIG. 7, the inner diameter 9 of FIG. Let r. If the inner diameter 9 projected onto the end face shown in FIG. 8 is a circumference 8, the radius of the circumference 8 is r.

  In the present invention, “wherein the inner radius of the cylindrical case is r, the position of the end of the hydrophobic hollow fiber membrane is a radius of 0. 0 from the center of the circle of the cylindrical case on the end surface of the cylindrical case. “Arranged in the circumferential region drawn by 9r” means that when the inner radius of the cylindrical case is r, all end portions of the hydrophobic hollow fiber membrane are placed in the circumferential region drawn by a radius of 0.9r. That there is.

  Details will be described with reference to the drawings. a) When the inner diameter of the cylindrical case in the hollow fiber membrane bundle body is larger or equal to the inner diameter of the end surface of the cylindrical case, as shown in FIG. 9, it is arranged in a circumferential region drawn with a radius of 0.9r. The hollow fiber membrane refers to a hollow fiber membrane in the circumferential region 7, and b) when the inner diameter of the cylindrical case in the hollow fiber membrane bundle body is smaller than the inner diameter of the end surface of the cylindrical case. As shown in FIG. 8, since the region drawn with the radius r becomes the circumferential region 8 arranged inside the cylindrical case end face inner diameter, the circumferential region drawn with the radius 0.9r is further inside thereof. This is a circumferential region 7.

  In the present invention, "the hollow fiber membrane at the outermost periphery of the hollow fiber membrane bundle at the end surface of the cylindrical case" means the center of any hollow fiber membrane present in the inner peripheral region of the cylindrical case at the end surface of the cylindrical case. Is a hollow fiber membrane that forms a straight line that is the outermost side from the center of the cylindrical case when each is connected by a straight line.

  FIG. 10 is an enlarged view of the end surface of the hollow fiber membrane module, and the details will be described. Here, in order to simplify the description, among the “arbitrary hollow fiber membranes existing in the inner peripheral region of the cylindrical case at the end surface of the cylindrical case”, the “circular shape of the cylindrical case at the end surface of the cylindrical case”. The “arbitrary hollow fiber membrane existing outside the circumferential region drawn with a predetermined radius from the center” will be taken out and described. In FIG. 10, there are 20 hollow fiber membranes a to t outside the circumferential region drawn with a predetermined radius from the center of the circle of the cylindrical case. When taking the hollow fiber membranes a, b, c, and d, the straight lines connecting adjacent hollow fiber membranes are ab, bc, and cd, but ad shown by a broken line is more outward from the center Z than these straight lines. Thus, the hollow fiber membranes a and d constituting the straight line ad are referred to as the outermost hollow fiber membranes of the hollow fiber membrane bundle at the end face of the cylindrical case. The hollow fiber membranes b and c are not the outermost periphery.

  When applied to all of a to t, twelve hollow fiber membranes (a, d, e, f, h, i, k, l, m, p, r, s) can be referred to as the outermost periphery. Based on the above concept, actually, “an arbitrary hollow fiber membrane existing in the inner peripheral region of the cylindrical case at the end face of the cylindrical case” is considered.

  In the present invention, “the portion where the hydrophobic hollow fiber membrane is located on the outermost periphery of the hollow fiber membrane bundle on the side surface of the hollow fiber membrane module” means that the hydrophobic hollow fiber membrane is on the side surface of the hollow fiber membrane module. The portion appearing on the outermost periphery of the hollow fiber membrane bundle is defined as the same concept as above. That is, in this case, not the end face of the above-described cylindrical case but the cross-section cut perpendicular to the axis of the hollow fiber membrane module, any hollow fiber membrane present in the inner peripheral region of the cylindrical case A hollow fiber membrane that forms a straight line that is the outermost side from the center of the cross section of the cylindrical case when the centers are connected to each other by a straight line. Whether or not the hydrophobic hollow fiber membrane in the cross section cut perpendicularly to the axis of the hollow fiber membrane module is positioned at the “outermost circumference” is confirmed, for example, with respect to the cross section at the portion where the overall length of the cylindrical case is divided into 10 equal parts Thus, the length of the portion where the hydrophobic hollow fiber membrane is located on the outermost periphery on the side surface of the cylindrical case can be confirmed.

  According to the present invention, even if air flows into the upstream side of the hollow fiber membrane module, it can be easily discharged out of the system through the hydrophobic hollow fiber membrane, and the flow rate does not decrease. In addition, the sheet that covers the hollow fiber membrane bundle so as not to spread can be removed at the time of manufacturing the module, and only the hollow hollow fiber membrane is lifted, and the hollow fiber membrane bundle is not disturbed. It is possible to avoid the crowding of hydrophilic hollow fiber membranes, it is easy to pass through water, and the filtration capacity is better because the surface of the hollow fiber membranes is easily removed due to shaking of the hollow fiber membranes and rubbing between the hollow fiber membranes. A high hollow fiber membrane module can be provided.

It is the schematic of a hollow fiber membrane module containing the sheet | seat which covers a hollow fiber membrane in the form which restrains. It is the schematic of the hollow fiber membrane module which does not contain a sheet | seat. It is a figure which shows the method of removing the sheet | seat in this invention hollow fiber membrane module. It is a schematic side view of a hollow fiber membrane module in which a hydrophobic hollow fiber membrane is disposed outside the hollow fiber membrane. It is an example of a defective hollow fiber membrane module in which a hydrophobic hollow fiber membrane is lifted. It is the schematic of the hollow fiber membrane module which does not contain a sheet | seat. It is the schematic of the hollow fiber membrane module which does not contain a sheet | seat. It is the end surface schematic of this invention module. It is the end surface schematic of this invention module. It is the end surface schematic of this invention module. It is embodiment schematic of this invention module. It is the schematic of the state before mixing a hydrophobic hollow fiber membrane with a hydrophilic hollow fiber membrane. It is an example of the schematic side view of this invention module. It is an example of the schematic side view of this invention module. It is an example of the schematic side view of this invention module. It is a water purifier cartridge schematic diagram incorporating a module.

  Embodiments of the present invention will be described below.

  The hollow fiber membrane module of the present embodiment is such that a hollow fiber membrane bundle 11 obtained by bundling a plurality of hollow fiber membranes and bending it into a U shape is fixed to a cylindrical case 3 with a potting material 4 as shown in FIG. is there. Here, the hollow fiber membrane bundle 11 is composed of a mixture of the hydrophilic hollow fiber membrane 1 and the hydrophobic hollow fiber membrane 2, and the hollow fiber membrane bundle 11 is arranged in an unconstrained state on the cylindrical case 3, and the module end face 6 The hollow fiber membrane bundle 11 is arranged so that all of the outermost hollow fiber membranes of the hollow fiber membrane bundle 11 become the hydrophilic hollow fiber membranes 1.

  “The hollow fiber membrane bundle 11 is disposed in the tubular case 3 in an unconstrained state” means that the hollow fiber membrane bundle 11 is disposed in the tubular case 3 without being restrained by the sheet 5 or the like. Say. That is, the sheet 5 may be interposed between the hollow fiber membrane bundle 11 and the cylindrical case 3, but the state where the hollow fiber membrane bundle 11 is not constrained by the sheet 5 or the like. Say.

  A method for producing the hollow fiber membrane module of the present invention will be described. After mixing the hydrophilic hollow fiber membrane 1 and the hydrophobic hollow fiber membrane 2, the U-shaped hollow fiber membrane bundle 11 is covered with the sheet 5, and after filling the cylindrical case 3, only the sheet 5 is removed, The opening end of the hollow fiber membrane bundle 11 is fixed to the opening of the cylindrical case 3 with the potting material 4.

  As a method of mixing the hydrophilic hollow fiber membrane 1 and the hydrophobic hollow fiber membrane 2, first, a plurality of hydrophilic hollow fiber membrane bundles 1 are flattened as shown in FIG. A method of wrapping the hydrophobic hollow fiber membrane 2 with a bundle of the hydrophilic hollow fiber membranes 1 or making a recess so that the bundle of the hydrophilic hollow fiber membranes 1 becomes concave, and the hydrophobic hollow fiber membrane 2 is formed in the recessed portion. There is a method of arranging and wrapping, but the former is preferable from the viewpoint of simplicity of work.

  In order to remove the sheet 5 in a later step, it is necessary to grip the open end of the hollow fiber membrane bundle 11 that is not covered with the sheet 5. Therefore, it is preferable to leave the open end of the hollow fiber membrane bundle 11 to be gripped without being covered with the sheet 5 and to cover the remaining part with the sheet 5.

  As a method of removing the sheet 5, there is a method of using a suction device 21 as shown in FIG. While fixing the open end of the hollow fiber membrane bundle 11 with the grip portion 22, the sheet 5 is extracted from the cylindrical case 3 by suction with air, and only the hollow fiber membrane bundle 11 is left in the cylindrical case 3. After gripping the hollow fiber membrane opening end with the gripping part 22, it may be directly pulled out by hand.

  Since the sheet 5 covering the hollow fiber membrane bundle 11 in the form of restraining the hollow fiber membrane bundle 11 is not left in the hollow fiber membrane module and the hollow fiber membrane bundle is not concentrated, the hollow fiber membrane is effectively used, and the water in the module The flow tends to improve and the turbid filtration capacity is improved.

  As the hydrophilic hollow fiber membrane 1, polysulfone, polyacrylonitrile, polyphenylene sulfone, polyphenylene sulfide sulfone, polyether sulfone, polyethylene is preferably used as a raw material polymer, and more preferably biological characteristics, heat resistance, chemical resistance, etc. Polysulfone that is excellent in water purification and suitable for water purifiers is preferable.

  The pore diameter of the hydrophilic hollow fiber membrane 1 is preferably 10 μm or less, more preferably 2 μm or less. Further, when removing fine solids, it is preferable to use those having a pore diameter of 0.1 μm or less because finer turbid components can be removed.

  As the hydrophobic hollow fiber membrane 2, polyethylene, polypropylene, polymethylpentene, polyvinylidene fluoride, polysulfone or the like is preferably used as a raw material polymer, more preferably polyethylene having the lowest polarity and the most hydrophobic.

  The potting material 4 only needs to be able to seal between the cylindrical case 3 and the hollow fiber membrane bundle 11 and between the hollow fiber membranes, and mix and react and harden a fluid main agent and a curing agent. Two-component mixed type epoxy resin, polyurethane resin, and the like are preferable because they are easy to handle in manufacturing the hollow fiber membrane module.

  As the sheet 5 that covers the U-shaped hollow fiber membrane bundle 11 and is pulled out in the subsequent process, a nonwoven fabric having a low frictional resistance is preferable so as not to damage the hollow fiber membrane.

  The hydrophobic hollow fiber membrane 2 in the hollow fiber membrane module is arranged inside the hydrophilic hollow fiber membrane 1 so that it cannot be seen from the outside, and the outermost hollow fiber membrane of the hollow fiber membrane bundle 11 is all on the module end surface 6. It is a hydrophilic hollow fiber membrane 1 and not a hydrophobic hollow fiber membrane 2. As shown in FIG. 12, the bundle of hydrophilic hollow fiber membranes 1 is flattened to have a width of about 5 to 10 cm, and several hydrophobic hollow fiber membranes 2 are placed thereon, By wrapping with a bundle of hydrophilic hollow fiber membranes 1 and then forming a U shape, the hydrophobic hollow fiber membranes when the inner radius of the cylindrical case 3 is r on the module end face 6 as shown in FIG. The two end portions can be arranged inside the region 7 drawn with a radius of 0.9 r from the center of the cylindrical case 3 on the end surface of the cylindrical case 3. As a result, the hydrophobic hollow fiber membrane 2 does not come off the grip portion 22. In order to further reduce the possibility of detachment from the grip portion 22, the thickness of the bundle of hydrophilic hollow fiber membranes 1 is set to 1 cm or more, several hydrophobic hollow fiber membranes 2 are placed, and the hydrophobic hollow fiber membranes 2 are made hydrophilic. The hollow fiber membrane bundle 11 can be placed in a circumferential region drawn at 0.7r by wrapping with a bundle of the conductive hollow fiber membrane 1 and then U-shaped, and when removing the sheet 5, the hollow fiber membrane bundle 11 There is no defect that only the hydrophobic hollow fiber membrane 2 comes off when the gripper is gripped, and the hydrophobic hollow fiber membrane 2 floats together with the sheet 5, and the hollow fiber membrane module can be manufactured stably. Since the sheet 5 is removed, the hollow fiber membrane module can be obtained, which prevents the hollow fiber membrane bundles 11 from being densely packed, has good water passage, has a high turbidity filtration capability, and can discharge stagnant air.

  When a part of the hydrophobic hollow fiber membrane 2 is located on the outermost periphery of the hollow fiber membrane bundle 11 on the side surface of the hollow fiber membrane module, the hydrophobic hollow of the portion located on the outermost periphery of the hollow fiber membrane bundle 11 When the length of the thread membrane 2 is 25% or less of the length of the cylindrical case 3, the probability that the hydrophobic hollow fiber membrane 2 is pulled out together with the sheet 5 when the sheet 5 is removed becomes low.

  Furthermore, if it is 10% or less, the probability of being pulled out becomes extremely low. The state in which the length of a part of the hydrophobic hollow fiber membrane 2 located on the outermost periphery of the hollow fiber membrane bundle 11 on the side surface of the hollow fiber membrane module is 25% or less of the cylindrical case 3 is shown in FIGS. It has a shape as shown in FIG. When the hydrophobic hollow fiber membrane 2 and the cylindrical case 3 can be contacted only at one place near the potting material 4 as shown in FIG. 13, the hydrophobic hollow fiber membrane 2 and the cylinder are placed only at one place near the mountain on the U-shape as shown in FIG. In the case where the cylindrical case 3 is in contact, the present invention includes any form such as the case where the hydrophobic hollow fiber membrane 2 and the cylindrical case 3 are in contact at two locations as shown in FIG.

  The ratio of the membrane area of the hydrophobic hollow fiber membrane 2 is preferably 0.05% to 5% with respect to the hydrophilic hollow fiber membrane 1. By setting the ratio of the hydrophobic hollow fiber membrane 2 to 0.05% or more, the ability to discharge stagnant air can be exhibited. Moreover, by setting it as 5% or less, it can have enough membrane area of a hydrophilic hollow fiber membrane, and can maintain a filtration capability. More preferably, the proportion of the hydrophobic hollow fiber membrane 2 is 0.05 to 0.5%.

  Here, the membrane area is calculated from the area of the outer surface of the wetted portion of the hollow fiber membrane, and does not include the portion bonded and fixed by the potting material 4.

  The hollow fiber membrane module of the present invention can be applied to various types of cartridges for water purifiers such as faucet direct connection type, stationary type, pot type, and undersink type. It is preferably used in combination with an adsorbent such as activated carbon, zeolite, inorganic ion exchanger, ion exchange resin, chelate resin, etc., which removes harmful substances such as trihalomethane and lead, and silver and copper to suppress bacterial growth Those having an antibacterial agent attached thereto, or those which remove chlorine from tap water are preferably used.

  It is also possible to use it as a water purifier equipped with a cartridge for the water purifier of the above form, and it is also possible to use it as a water purifier equipped with only the hollow fiber membrane module of the present invention without using it together with the adsorbent as described above. is there.

  Hereinafter, the present invention will be described more specifically with reference to examples. The hydrophobic hollow fiber membrane was counted as defective when it floated 2 mm or more against the hydrophilic hollow fiber membrane bundle in the module.

  The turbidity filtration capacity test of the water purifier cartridge was carried out in accordance with the method shown in JIS S 3201: 2004 (house water purifier test method).

[Example 1]
A polysulfone hollow fiber membrane (average outer diameter = 0.46 mm) is used as the hydrophilic hollow fiber membrane, and a polyethylene hollow fiber membrane (average outer diameter = 0.65 mm) is used as the hydrophobic hollow fiber membrane. As shown in FIG. 888 hollow fiber membranes are flattened to a width of about 5 cm, 2 to 5 hydrophobic hollow fiber membranes are placed thereon, mixed so as to be wrapped inside the hydrophilic hollow fiber membrane, and U-shaped. The hollow fiber membrane bundle was wrapped with a nonwoven fabric used as a sheet, and inserted into a cylindrical case (inner diameter = 26.5 mm, length = 86.5 mm). After the insertion, the open end of the hollow fiber membrane bundle was gripped, the non-woven fabric enclosing the hollow fiber membrane bundle was removed, and the open end was fixed with polyurethane resin to obtain a hollow fiber membrane module. 100 pieces were manufactured, and the occurrence rate of the lifting failure of the hydrophobic hollow fiber membrane was confirmed. As shown in Table 1, it was 0%, which was a significant improvement over Comparative Example 1. The arrangement of the hydrophobic hollow fiber membranes on the end face of the module was distributed as shown in Table 2, and all were arranged in a circumferential region drawn with a radius of 0.9r from the center of the circle of the cylindrical case. The ratio of the length of a part of the hydrophobic hollow fiber membrane located on the outermost periphery of the hollow fiber membrane bundle on the side surface of the hollow fiber membrane module to the length of the cylindrical case is as shown in Table 3, all being 25% or less. It was.

[Comparative Example 1]
Polysulfone hollow fiber membranes (average outer diameter = 0.46 mm) are used as hydrophilic hollow fiber membranes, and polyethylene hollow fiber membranes (average outer diameter = 0.65 mm) are used as hydrophobic hollow fiber membranes. 888 hydrophilic hollow fiber membranes When mixing 2 to 5 hydrophobic hollow fiber membranes, mix without considering the arrangement of the hydrophobic hollow fiber membranes, make U-shaped, wrap the hollow fiber membrane bundle with non-woven fabric, cylindrical cylindrical case (Inner diameter = 26.5 mm, length = 86.5 mm). After the insertion, the open end of the hollow fiber membrane bundle was gripped, the non-woven fabric enclosing the hollow fiber membrane bundle was removed, and the open end was fixed with polyurethane resin to obtain a hollow fiber membrane module. When 100 pieces were manufactured and the rising defect occurrence rate of the hydrophobic hollow fiber membrane was confirmed, it was 30%. In addition, the arrangement of the hydrophobic hollow fiber membranes on the end face of the module has the distribution as shown in Table 2, and it is defective by being arranged outside the circumferential region drawn with a radius of 0.9r from the center of the circle of the cylindrical case. The rate goes up. The ratio of the length of a part of the hydrophobic hollow fiber membrane located on the outermost periphery of the hollow fiber membrane on the side surface of the hollow fiber membrane module to the cylindrical case length is as shown in Table 3, and it is 25% or more. A floating defect was confirmed.
[Example 2]
A polysulfone hollow fiber membrane (average outer diameter = 0.46 mm) is used as the hydrophilic hollow fiber membrane, and a polyethylene hollow fiber membrane (average outer diameter = 0.65 mm) is used as the hydrophobic hollow fiber membrane. As shown in FIG. 2 to 5 hydrophobic hollow fiber membranes are mixed with 888 hollow fiber membranes so as to be wrapped inside the hydrophilic hollow fiber membrane, and U-shaped, and the hollow fiber membrane bundle is wrapped with a non-woven fabric. (Inner diameter = 26.5 mm, length = 86.5 mm). After the insertion, the open end of the hollow fiber membrane bundle was gripped, the non-woven fabric enclosing the hollow fiber membrane bundle was removed, and the open end was fixed with polyurethane resin to obtain a hollow fiber membrane module. The hollow fiber membrane module is inserted into a cylindrical main body container having an opening inner diameter of 53.7 mm and a height of 97.5 mm, and charged with 38.5 g of activated carbon having a particle size ranging from 48 mesh to 100 mesh. A water purifier cartridge having the shape shown in FIG. 16 was obtained. In FIG. 16, reference numeral 31 denotes a hollow fiber membrane module, 32 denotes an activated carbon filling portion, and 33 denotes a cartridge main body container. Based on JIS S3201 "Household water purifier test method" with this cartridge, the turbidity filtration ability test was carried out at a display filtration flow rate of 2.0 L / min. As a result, the total amount of filtrate water until it decreased to 1/2 of the indicated filtration flow rate was 5250 L, and the filtration capacity was improved as compared with the case where the hollow fiber membrane module includes a nonwoven fabric.
[Comparative Example 2]
A polysulfone hollow fiber membrane (average outer diameter = 0.46 mm) is used as the hydrophilic hollow fiber membrane, and a polyethylene hollow fiber membrane (average outer diameter = 0.65 mm) is used as the hydrophobic hollow fiber membrane. As shown in FIG. 2 to 5 hydrophobic hollow fiber membranes are mixed with 888 hollow fiber membranes so as to be wrapped inside the hydrophilic hollow fiber membrane, and U-shaped, and the hollow fiber membrane bundle is wrapped with a non-woven fabric. (Inner diameter = 26.5 mm, length = 86.5 mm). After the insertion, the open end was fixed with a polyurethane resin while leaving the non-woven fabric enclosing the hollow fiber membrane bundle without removing it, thereby obtaining a module. The hollow fiber membrane module is inserted into a cylindrical main body container having an opening inner diameter of 53.7 mm and a height of 97.5 mm, and charged with 38.5 g of activated carbon having a particle size ranging from 48 mesh to 100 mesh. A water purifier cartridge was obtained. Based on JIS S3201 "Household water purifier test method" with this cartridge, the turbidity filtration ability test was carried out at a display filtration flow rate of 2.0 L / min. As a result, the total amount of filtrate water until it decreased to 1/2 of the indicated filtration flow rate was 3450L.

  The present invention can be applied to water purifiers in general, such as a faucet direct connection type, a stationary type, a pot type, and an undersink type, but is not limited thereto.

DESCRIPTION OF SYMBOLS 1 Hydrophilic hollow fiber membrane 2 Hydrophobic hollow fiber membrane 3 Cylindrical case 4 Potting material 5 Sheet 6 Hollow fiber membrane module end surface 7 The area | region drawn with a radius 0.9r in a cylindrical case end surface With a radius r in a cylindrical case end surface The drawn region 9 The inner diameter 10 of the cylindrical case in the hollow fiber membrane body portion The region 11 drawn with a predetermined radius on the end surface of the cylindrical case 11 The hollow fiber membrane bundle 21 The suction device 22 The hollow fiber membrane bundle gripping portion 31 The hollow fiber membrane module 32 The activated carbon Filler 33 Cartridge body container

Claims (8)

A hollow fiber membrane module in which a hollow fiber membrane bundle is filled in a U-shape in a cylindrical case, and an opening end of the hollow fiber membrane bundle is fixed to an opening of the cylindrical case with a potting material, the hollow fiber membrane module The membrane bundle is a mixture of a hydrophilic hollow fiber membrane and a hydrophobic hollow fiber membrane, and the hollow fiber membrane bundle is housed in the cylindrical case in an unconstrained state, and the hollow fiber is provided at an end surface of the cylindrical case. A hollow fiber membrane module characterized in that all of the hollow fiber membranes on the outermost periphery of the membrane bundle are the hydrophilic hollow fiber membranes. A circle in which the position of the end of the hydrophobic hollow fiber membrane is drawn with a radius of 0.9r from the center of the circle of the cylindrical case on the end surface of the cylindrical case, where r is the inner radius of the cylindrical case The hollow fiber membrane module according to claim 1, wherein the hollow fiber membrane module is disposed in a peripheral region. A hollow fiber membrane module in which a hollow fiber membrane bundle is filled in a U-shape in a cylindrical case, and an opening end of the hollow fiber membrane bundle is fixed to an opening of the cylindrical case with a potting material, the hollow fiber membrane module The membrane bundle is a mixture of a hydrophilic hollow fiber membrane and a hydrophobic hollow fiber membrane, and the hollow fiber membrane bundle is housed in the cylindrical case in an unconstrained state, and the hydrophobic fiber membrane module has a hydrophobic surface on the side surface of the hollow fiber membrane module. A hollow fiber membrane module, wherein the length of the portion of the hollow fiber membrane membrane located at the outermost periphery of the hollow fiber membrane bundle is 25% or less of the length of the cylindrical case. The hollow fiber membrane module according to any one of claims 1 to 3, wherein a ratio of a membrane area of the hydrophobic hollow fiber membrane to a membrane area of the hydrophilic hollow fiber membrane is 0.05 to 5%. . After making the hollow fiber membrane bundle into a U shape, the hollow fiber membrane bundle is covered with a sheet all around, filled into a cylindrical case in a state of being wrapped in the sheet, and then the open end of the hollow fiber membrane bundle with a potting material A hollow fiber membrane module manufacturing method for fixing a hollow hollow fiber membrane to the opening of the cylindrical case, wherein the hollow fiber membrane bundle is a mixture of a hydrophilic hollow fiber membrane and a hydrophobic hollow fiber membrane. A hollow fiber membrane is wrapped inside the bundle of hydrophilic hollow fiber membranes to form the hollow fiber membrane bundle, and then U-shaped. After the hollow fiber membrane bundle is filled in the cylindrical case, the sheet is removed. A method for producing a hollow fiber membrane module. The cartridge for water purifiers which mounts the hollow fiber membrane module in any one of Claims 1-4. The water purifier which mounts the hollow fiber membrane module in any one of Claims 1-4. A water purifier equipped with the water purifier cartridge according to claim 6.

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