JP2012139615A - Spiral type separation membrane element and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spiral type separation membrane element which needs no telescope prevention plate and is excellent in long-term stability and to provide a method for producing the same.SOLUTION: The spiral type separation membrane element is constituted by spirally winding up a stock solution passage material and a separation membrane unit which is equipped with a permeated liquid passage material in an envelope-shaped membrane formed by laminating and adhering separation membranes around a perforated water collecting pipe. The spiral type separation membrane element is characterized in that a resin 10 is arranged so that the projected area ratio of at least one side of a zonal end part between both sides of zonal end parts in the longitudinal direction of the perforated water collecting pipe at the surface of the separation membrane unit is above 0 and under 1.

Description

  The present invention relates to a spiral separation membrane element that uses a separation membrane to separate components of a fluid by reverse osmosis technology, filtration technology, and the like, and a method for manufacturing the same.

  There are various types of separation membranes that separate liquids, etc., depending on the pore size and separation function. However, in terms of supplying undiluted solution to one side of the separation membrane and taking out permeate from the other side. It is common. For example, as a fluid separation element used for reverse osmosis filtration, ultrafiltration, etc., a raw liquid flow path material that guides a supply-side fluid (raw solution) to the surface of the separation membrane, a separation membrane that separates a supply-side fluid (permeate), and There is a spiral type separation membrane element in which a unit made of a permeate flow path material that guides a supply side fluid that passes through a separation membrane and is separated from a supply side fluid to a water collecting pipe (center pipe) is wound around a perforated center pipe Are known.

  FIG. 1 is a partially developed perspective view schematically showing a member configuration of a conventional spiral separation membrane element. A spiral separation membrane element 1 shown in FIG. 1 forms a separation membrane unit 7 having a permeate flow path material 6 in an envelope-like membrane bonded with a separation membrane 5 superimposed thereon, and the separation membrane unit 7 Are attached to the water collecting pipe 2 made of a perforated hollow tube, and are wound around the outer peripheral surface of the water collecting pipe 2 together with a net-like (net-like) stock solution channel material 4 in a spiral shape. As shown in FIG. 1, the stock solution 31 is supplied from one end face side of the spiral separation membrane element 1. The supplied stock solution 31 flows along the stock solution channel material 4 and is discharged as a concentrated solution 33 from the other end face side of the spiral separation membrane element 1. The permeate 32 that has permeated through the separation membrane 5 in the course of the stock solution 31 flowing along the stock solution channel material 4 flows into the water collection pipe 2 along the permeate flow channel material 6 and is discharged from the end of the water collection tube 2. The The spiral separation membrane element as described above has one set or a plurality of sets of material groups (leafs) composed of the separation membrane 5 formed in an envelope shape with the permeate flow passage material 6 interposed therebetween and the raw solution flow passage material 4. .

  2 is a sectional view in the axial direction of a spiral separation membrane element having a plurality of sets of material groups, FIG. 3 is a sectional view taken along line AA of the spiral separation membrane element in FIG. 2, and FIG. 4 is a spiral separation in FIG. It is an end view of a membrane element.

  When manufacturing the spiral separation membrane element 1, the folded separation membrane 5, the undiluted solution channel material 4, and the permeate channel material 6 are overlapped, and two sheets are back to back through the permeate channel material 6. The separation membrane 5 is spirally wound around the outer peripheral surface of the water collecting pipe 2 as shown in FIGS. Then, as shown in FIG. 2, the spiral separation membrane element is deformed into a telescope (telescope) shape on both end faces of the material group wound around the water collecting pipe 2 due to pressure loss generated when the fluid passes. In general, the telescope prevention plate 8 is attached to prevent the separation performance from deteriorating. Further, the telescope prevention plate 8 winds and fixes the filament impregnated with the adhesive 9 on the outer surface of the spiral separation membrane element 1 in order to seal and fix the spiral separation membrane element 1. The telescope prevention plate 8 has a structure in which a seal member can be attached so that the container filled with the spiral separation membrane element 1 and the spiral separation membrane element 1 can be sealed.

  In recent years, there has been a growing need for cost reduction in membrane separation devices such as spiral-type separation membrane elements due to an increase in water production costs. However, the use of many members as described above increases costs and complicates the manufacturing process, which is a hindrance. On the other hand, while the problem of the environmental load of the consumer material has been attracting attention in recent years, the environmental load is also a problem for the spiral membrane element that is discarded with a certain period of life.

  Against this background, Patent Document 1 proposes a spiral separation membrane element 1 that does not use the telescope prevention plate 8 by supporting the end face of the element with the lid plate portion of the container filled with the spiral separation membrane element. Has been. According to the present invention, it is not necessary to firmly seal the space between the spiral separation membrane element 1 and the telescope prevention plate 8 by filament winding as in the prior art, thereby improving productivity by reducing the number of processes and reducing material costs. Reduction is possible.

JP-A-7-313848

  However, the above-described separation membrane element is not sufficient in terms of performance stability when operated by applying pressure over a long period of time.

  Therefore, an object of the present invention is to provide a spiral separation membrane element that does not require a telescope prevention plate and has excellent long-term stability, and a method for manufacturing the same.

  To achieve the above object, the present invention has the following configuration.

  (1) A separation membrane unit provided with a permeate flow path material and a raw liquid flow path material are spirally wound around a perforated water collecting pipe in an envelope membrane adhered by overlapping the separation membranes. In the spiral separation membrane element, the projected area ratio of at least one of the strip-shaped end portions on both sides in the longitudinal direction of the perforated water collecting pipe on the surface of the separation membrane unit exceeds 0 and is less than 1 A spiral separation membrane element characterized in that the resin is arranged as described above.

  (2) The spiral separation membrane element according to (1), wherein the projected area ratio is 0.01 or more and 0.3 or less.

  (3) The spiral separation membrane element according to (1) or (2), wherein the resin pattern disposed on the belt-like end portion is dot-like.

  (4) Spiral that surrounds a separation membrane unit having a permeate flow passage material and a raw liquid flow passage material in a spiral shape around a perforated water collecting pipe in an envelope-like separation membrane that is bonded by overlapping the separation membranes A method of manufacturing a mold separation membrane element, wherein the projected area ratio of at least one of the strip-shaped end portions on both sides of the perforated water collecting pipe in the longitudinal direction on the surface of the separation membrane unit is more than 0 and less than 1 A process for producing a spiral separation membrane element, characterized in that a resin is arranged so that

  According to the present invention, a resin having a specific projected area ratio is indispensable for a conventional spiral separation membrane element by disposing a resin at the band-like end in the longitudinal direction of the perforated water collecting pipe on the surface of the separation membrane unit. The telescopic prevention plate and the filament winding that firmly seals the spiral separation membrane element and the telescope prevention plate are not required. As a result, it is possible to obtain a high-performance, high-efficiency separation membrane element that can reduce the raw material cost of the separation membrane element, simplify the manufacturing process, and reduce the environmental load.

It is the partial expansion perspective view which showed typically the member structure of the conventional spiral type separation membrane element. It is sectional drawing of the axial direction of the conventional spiral type separation membrane element which has a some raw material group. FIG. 3 is a cross-sectional view of the spiral separation membrane element of FIG. 2 taken along line AA and unfolding the separation membrane unit. FIG. 3 is a developed cross-sectional view at an end surface of the spiral separation membrane element of FIG. 2. It is an expanded sectional view in the end face of the spiral type separation membrane element in the 1st example of the present invention. FIG. 6 is a development view before enclosing the spiral separation membrane element of FIG. 5 in which a resin is disposed at both end portions on the surface of the separation membrane unit. FIG. 6 is a development view before enclosing a spiral separation membrane element in a second embodiment of the present invention, in which resin is disposed on one side of a band-shaped end portion on the surface of a separation membrane unit.

  Hereinafter, the present invention will be described in more detail.

  In the present invention, the separation membrane unit 7 provided with the permeate passage material 6 and the stock solution passage material 4 are spirally formed around the perforated water collecting pipe 2 in an envelope-like membrane bonded with the separation membrane 5 superimposed. The projected area ratio of at least one of the strip-shaped end portions on the surface of the separation membrane unit 7 in the longitudinal direction of the perforated water collecting pipe 2 on both sides in the longitudinal direction. The spiral-type separation membrane element 1 is characterized in that the resin 10 is disposed so as to exceed 0 and less than 1.

  Here, the separation membrane 5 is not limited as long as it separates components in the fluid supplied to the surface of the separation membrane and obtains a permeated fluid that has permeated through the separation membrane. However, the separation functional layer, the porous support membrane, What consists of a base material is used preferably. As the separation functional layer, a crosslinked polymer is preferably used in terms of pore size control and durability, and polyfunctional amine and polyfunctional acid halide are polycondensed on the porous support membrane in terms of component separation performance. A polyamide separation functional layer, an organic / inorganic hybrid functional layer, and the like can be suitably used. A membrane having a separation function and a support function such as a cellulose membrane, a PVDF membrane, a PES membrane, or a polysulfone membrane can also be used.

  In this invention, the case where the polyamide which comprises a separation function layer is used is explained in full detail. The polyamide film can be formed by interfacial polycondensation of a polyfunctional amine and a polyfunctional acid halide. Here, it is preferable that at least one of the polyfunctional amine or the polyfunctional acid halide contains a trifunctional or higher functional compound.

  Here, the polyfunctional amine has at least two primary amino groups and / or secondary amino groups in one molecule, and at least one of the amino groups is a primary amino group. An amine, for example, phenylenediamine, xylylenediamine, 1,3,5-triaminobenzene, in which two amino groups are bonded to the benzene ring in any of the ortho, meta, and para positions. , 2,4-triaminobenzene, 3,5-diaminobenzoic acid, 3-aminobenzylamine, aromatic polyfunctional amines such as 4-aminobenzylamine, aliphatic amines such as ethylenediamine and propylenediamine, 1,2- Examples include alicyclic polyfunctional amines such as diaminocyclohexane, 1,4-diaminocyclohexane, 4-aminopiperidine, and 4-aminoethylpiperazine. It is possible. Among them, considering the selective separation property, permeability, and heat resistance of the membrane, it may be an aromatic polyfunctional amine having 2 to 4 primary amino groups and / or secondary amino groups in one molecule. Preferably, as such a polyfunctional aromatic amine, m-phenylenediamine, p-phenylenediamine, and 1,3,5-triaminobenzene are preferably used. Among these, it is more preferable to use m-phenylenediamine (hereinafter referred to as m-PDA) from the standpoint of availability and ease of handling. These polyfunctional amines may be used alone or in combination of two or more. When using 2 or more types simultaneously, the said amines may be combined and the said amine and the amine which has at least 2 secondary amino group in 1 molecule may be combined. Examples of the amine having at least two secondary amino groups in one molecule include piperazine and 1,3-bispiperidylpropane.

  The polyfunctional acid halide refers to an acid halide having at least two carbonyl halide groups in one molecule. Examples of trifunctional acid halides include trimesic acid chloride, 1,3,5-cyclohexanetricarboxylic acid trichloride, 1,2,4-cyclobutanetricarboxylic acid trichloride, and bifunctional acid halides include biphenyl dicarboxylic acid. Aromatic difunctional acid halides such as acid dichloride, azobenzene dicarboxylic acid dichloride, terephthalic acid chloride, isophthalic acid chloride, naphthalene dicarboxylic acid chloride, aliphatic difunctional acid halides such as adipoyl chloride, sebacoyl chloride, cyclopentane Examples thereof include alicyclic difunctional acid halides such as dicarboxylic acid dichloride, cyclohexane dicarboxylic acid dichloride, and tetrahydrofuran dicarboxylic acid dichloride. Considering the reactivity with the polyfunctional amine, the polyfunctional acid halide is preferably a polyfunctional acid chloride, and considering the selective separation property and heat resistance of the membrane, 2 to 4 per molecule. The polyfunctional aromatic acid chloride having a carbonyl chloride group is preferred. Among them, it is more preferable to use trimesic acid chloride from the viewpoint of easy availability and easy handling. These polyfunctional acid halides may be used alone or in combination of two or more.

  In terms of maintaining the separation performance, the ratio of the bifunctional acid halogen compound to the trifunctional halogen compound is 0.05 to 1.5 in terms of molar ratio (mole of the bifunctional acid halogen compound / mole of the trifunctional acid halogen compound). It is preferable that it is 0.1 to 1.0.

  Further, a separation membrane having an organic / inorganic hybrid structure containing Si element or the like in terms of chemical resistance of the separation functional layer can be used. The organic-inorganic hybrid film is not particularly limited. For example, (A) a silicon compound in which a reactive group having an ethylenically unsaturated group and a hydrolyzable group are directly bonded to a silicon atom, and (B) other than the silicon compound Condensation of the hydrolyzable group of the silicon compound (A) with the compound having an ethylenically unsaturated group of (A) and the ethylenic unsaturated of the compound (A) and the compound (B) having an ethylenically unsaturated group. Saturated polymer can be used.

  First, the silicon compound (A) in which a reactive group having an ethylenically unsaturated group and a hydrolyzable group are directly bonded to a silicon atom will be described.

  The reactive group having an ethylenically unsaturated group is directly bonded to the silicon atom. Examples of such reactive groups include vinyl groups, allyl groups, methacryloxyethyl groups, methacryloxypropyl groups, acryloxyethyl groups, acryloxypropyl groups, and styryl groups. From the viewpoint of polymerizability, a methacryloxypropyl group, an acryloxypropyl group, and a styryl group are preferable.

  Further, through a process in which a hydrolyzable group directly bonded to a silicon atom is changed to a hydroxyl group, a condensation reaction occurs in which silicon compounds are bonded together by a siloxane bond, resulting in a polymer. Examples of hydrolyzable groups include functional groups such as alkoxy groups, alkenyloxy groups, carboxy groups, ketoxime groups, aminohydroxy groups, halogen atoms and isocyanate groups. As an alkoxy group, a C1-C10 thing is preferable, More preferably, it is a C1-C2 thing. The alkenyloxy group preferably has 2 to 10 carbon atoms, more preferably 2 to 4 carbon atoms, and further 3 carbon atoms. As the carboxy group, those having 2 to 10 carbon atoms are preferable, and further, those having 2 carbon atoms, that is, an acetoxy group. Examples of the ketoxime group include a methyl ethyl ketoxime group, a dimethyl ketoxime group, and a diethyl ketoxime group. The aminohydroxy group is one in which an amino group is bonded to a silicon atom via an oxygen atom via oxygen. Examples of such include dimethylaminohydroxy group, diethylaminohydroxy group, and methylethylaminohydroxy group. As the halogen atom, a chlorine atom is preferably used.

  In forming the separation functional layer, a silicon compound in which a part of the hydrolyzable group is hydrolyzed and has a silanol structure can be used. In addition, two or more silicon compounds having a high molecular weight such that a part of the hydrolyzable group is not hydrolyzed, condensed, or crosslinked can be used.

The silicon compound (A) is preferably represented by the following general formula (a).
Si (R ¹ ) _m (R ² ) _n (R ³ ) _4-mn (a)
(R ¹ represents a reactive group containing an ethylenically unsaturated group. R ² represents an alkoxy group, an alkenyloxy group, a carboxy group, a ketoxime group, a halogen atom or an isocyanate group. R ³ represents H or alkyl. M and n are integers satisfying m + n ≦ 4 and satisfy m ≧ 1 and n ≧ 1 In each of R ¹ , R ² and R ³ , two or more functional groups are bonded to a silicon atom. They may be the same or different.)
R ¹ is a reactive group containing an ethylenically unsaturated group, and is as described above.

R ² is a hydrolyzable group, and these are as described above. The number of carbon atoms of the alkyl group to be R ³ is preferably 1-10, and more preferably 1-2.

  As the hydrolyzable group, an alkoxy group is preferably used in forming the separation functional layer because the reaction solution has viscosity.

  Such silicon compounds include vinyltrimethoxysilane, vinyltriethoxysilane, styryltrimethoxysilane, methacryloxypropylmethyldimethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxypropylmethyldiethoxysilane, methacryloxypropyltriethoxy. Examples include silane and acryloxypropyltrimethoxysilane.

  In addition to the silicon compound of (A), a silicon compound having no hydrolyzable group can also be used in combination with no reactive group having an ethylenically unsaturated group. Such a silicon compound is defined as “m ≧ 1” in the general formula (a), and examples thereof include compounds in which m is zero in the general formula (a). Examples of such include tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, and methyltriethoxysilane.

  Next, the compound (B) having an ethylenically unsaturated group other than the silicon compound (A) will be described.

  The ethylenically unsaturated group has addition polymerizability. Examples of such compounds include ethylene, propylene, methacrylic acid, acrylic acid, styrene, and derivatives thereof.

  In addition, this compound may be an alkali-soluble compound having an acid group in order to increase the selective permeability of water and increase the salt rejection when a composite semipermeable membrane is used for separation of an aqueous solution. preferable.

  Preferred acid structures are carboxylic acid, phosphonic acid, phosphoric acid, and sulfonic acid, and these acid structures may exist in any form of acid form, ester compound, and metal salt. These compounds having one or more ethylenically unsaturated groups may contain two or more acids, but among them, compounds containing 1 to 2 acid groups are preferred.

  Examples of the compound having a carboxylic acid group among the compounds having one or more ethylenically unsaturated groups include the following. Maleic acid, maleic anhydride, acrylic acid, methacrylic acid, 2- (hydroxymethyl) acrylic acid, 4- (meth) acryloyloxyethyl trimellitic acid and the corresponding anhydride, 10-methacryloyloxydecylmalonic acid, N- ( 2-hydroxy-3-methacryloyloxypropyl) -N-phenylglycine and 4-vinylbenzoic acid.

  Among the compounds having at least one ethylenically unsaturated group, compounds having a phosphonic acid group include vinylphosphonic acid, 4-vinylphenylphosphonic acid, 4-vinylbenzylphosphonic acid, 2-methacryloyloxyethylphosphonic acid. 2-methacrylamidoethylphosphonic acid, 4-methacrylamido-4-methyl-phenyl-phosphonic acid, 2- [4- (dihydroxyphosphoryl) -2-oxa-butyl] -acrylic acid and 2- [2-dihydroxyphosphoryl] ) -Ethoxymethyl] -acrylic acid-2,4,6-trimethyl-phenyl ester.

  Among the compounds having one or more ethylenically unsaturated groups, the phosphate ester compounds include 2-methacryloyloxypropyl monohydrogen phosphate, 2-methacryloyloxypropyl dihydrogen phosphate, and 2-methacryloyloxyethyl monoester. Hydrogen phosphate and 2-methacryloyloxyethyl dihydrogen phosphate, 2-methacryloyloxyethyl-phenyl-hydrogen phosphate, dipentaerythritol-pentamethacryloyloxyphosphate, 10-methacryloyloxydecyl-dihydrogen phosphate, dipentaerythritol penta Methacryloyloxyphosphate, phosphoric acid mono- (1-acryloyl-piperidin-4-yl) -ester, 6- (methacrylamide) hexyl dihydrogen phosphate and 1,3-bis- (N-acryloyl-N-pro Le - amino) - propan-2-yl - dihydrogen phosphate are exemplified.

  Among the compounds having one or more ethylenically unsaturated groups, examples of the compound having a sulfonic acid group include vinylsulfonic acid, 4-vinylphenylsulfonic acid, and 3- (methacrylamide) propylsulfonic acid.

  In the separation membrane according to the present invention, in order to form the separation functional layer, in addition to the silicon compound of (A), a reaction liquid containing a compound having one or more ethylenically unsaturated groups and a polymerization initiator is used. The In addition to coating the reaction solution on the porous membrane and condensing the hydrolyzable groups, it is necessary to increase the molecular weight of these compounds by polymerization of ethylenically unsaturated groups. When the silicon compound of (A) is condensed alone, the bond of the crosslinking chain concentrates on the silicon atom, and the density difference between the silicon atom periphery and the part away from the silicon atom increases, so the pore size in the separation functional layer Tends to be non-uniform. On the other hand, in addition to the high molecular weight and cross-linking of the silicon compound itself of (A), the cross-linking point due to condensation of hydrolyzable groups and the ethylenically unsaturated group are copolymerized with the compound (B) having an ethylenically unsaturated group. Crosslink points due to polymerization of saturated groups are moderately dispersed. By appropriately dispersing the crosslinking points in this manner, a separation functional layer having a uniform pore diameter is formed, and a composite semipermeable membrane having a balance between water permeability and removal performance can be obtained. At this time, a compound having one or more ethylenically unsaturated groups is required to have a high molecular weight since it may be eluted when using a separation membrane if it has a low molecular weight, causing a decrease in membrane performance.

  In the method for producing a separation membrane according to the present invention, (A) the content of a silicon compound in which a reactive group having an ethylenically unsaturated group and a hydrolyzable group are directly bonded to a silicon atom is the solid content contained in the reaction solution. The amount is preferably 10 parts by weight or more, more preferably 20 parts by weight to 50 parts by weight with respect to 100 parts by weight. Here, the solid content contained in the reaction solution is obtained by the above production method except for all components contained in the reaction solution, excluding the solvent and distilled components such as water and alcohol produced by the condensation reaction. It refers to the component finally contained in the separation membrane as a separation functional layer. When the amount of the silicon compound (A) is small, the degree of crosslinking tends to be insufficient, so that there is a possibility that problems such as elution of the separation functional layer during membrane filtration and deterioration of separation performance may occur.

  The content of the compound (B) having an ethylenically unsaturated group is preferably 90 parts by weight or less, more preferably 50 parts by weight to 80 parts by weight with respect to 100 parts by weight of the solid content contained in the reaction solution. It is. When the content of the compound (B) is in these ranges, the resulting separation functional layer has a high degree of crosslinking, and thus membrane filtration can be performed stably without the separation functional layer eluting.

  Next, a method for forming a separation functional layer on a porous support membrane in the method for producing a separation membrane according to the present invention will be described.

  Examples of methods for forming the separation functional layer include a step of applying a reaction solution containing the silicon compound (A) and a compound (B) having an ethylenically unsaturated group, a step of removing the solvent, ethylene The step of polymerizing the polymerizable unsaturated group and the step of condensing the hydrolyzable group are performed in this order. In the step of polymerizing the ethylenically unsaturated group, the hydrolyzable group may be condensed at the same time.

  First, the reaction liquid containing (A) and (B) is brought into contact with the porous support membrane. Such a reaction solution is usually a solution containing a solvent, but such a solvent does not destroy the porous support membrane and dissolves (A) and (B) and a polymerization initiator added as necessary. If it is, it will not specifically limit. To this reaction solution, 1 to 10 times mol amount, preferably 1 to 5 times mol amount of water with respect to the number of moles of the silicon compound of (A) is added together with inorganic acid or organic acid, and (A) It is preferable to promote hydrolysis of the silicon compound.

  As the solvent for the reaction solution, water, an alcohol-based organic solvent, an ether-based organic solvent, a ketone-based organic solvent, and a mixture thereof are preferable. For example, as an alcohol organic solvent, methanol, ethoxymethanol, ethanol, propanol, butanol, amyl alcohol, cyclohexanol, methylcyclohexanol, ethylene glycol monomethyl ether (2-methoxyethanol), ethylene glycol monoacetate, diethylene glycol monomethyl ether, Examples include diethylene glycol monoacetate, propylene glycol monoethyl ether, propylene glycol monoacetate, dipropylene glycol monoethyl ether, and methoxybutanol. Examples of ether organic solvents include methylal, diethyl ether, dipropyl ether, dibutyl ether, diamyl ether, diethyl acetal, dihexyl ether, trioxane, dioxane and the like. Also, ketone organic solvents include acetone, methyl ethyl ketone, methyl propyl ketone, methyl isobutyl ketone, methyl amyl ketone, methyl cyclohexyl ketone, diethyl ketone, ethyl butyl ketone, trimethylnonanone, acetonitrile acetone, dimethyl oxide, phorone, cyclohexanone, dye Acetone alcohol etc. are mentioned. Moreover, as an addition amount of a solvent, 50 to 99 weight% is preferable, Furthermore, 80 to 99 weight% is preferable. If the amount of the solvent added is too large, defects tend to occur in the membrane, and if it is too small, the water permeability of the resulting separation membrane tends to be low.

  The contact between the porous support membrane and the reaction solution is preferably performed uniformly and continuously on the surface of the porous support membrane. Specifically, for example, there is a method in which the reaction solution is coated on the porous support film using a coating device such as a spin coater, a wire bar, a flow coater, a die coater, a roll coater, or a spray. Moreover, the method of immersing a porous support membrane in a reaction liquid can be mentioned.

  When immersed, the contact time between the porous support membrane and the reaction solution is preferably in the range of 0.5 to 10 minutes, and more preferably in the range of 1 to 3 minutes. After the reaction solution is brought into contact with the porous support membrane, it is preferable to sufficiently drain the liquid so that no droplets remain on the membrane. By sufficiently draining the liquid, it is possible to prevent the remaining portion of the liquid droplet from becoming a film defect after the film is formed and deteriorating the film performance. As a method for draining liquid, the porous support membrane after contact with the reaction liquid is vertically gripped to allow the excess reaction liquid to flow down naturally, or air such as nitrogen is blown from an air nozzle to forcibly drain the liquid. A method or the like can be used. In addition, after draining, the membrane surface can be dried to remove a part of the solvent in the reaction solution.

  The step of condensing the hydrolyzable group of silicon is performed by performing a heat treatment after bringing the reaction solution into contact with the porous support membrane. The heating temperature at this time is required to be lower than the temperature at which the porous support membrane melts and the performance as a separation membrane decreases. In order to allow the condensation reaction to proceed rapidly, it is usually preferred to heat at 0 ° C. or higher, more preferably 20 ° C. or higher. Further, the reaction temperature is preferably 150 ° C. or lower, and more preferably 100 ° C. or lower. If the reaction temperature is 0 ° C. or higher, the hydrolysis and condensation reaction proceed rapidly, and if it is 150 ° C. or lower, the hydrolysis and condensation reaction are easily controlled. Further, by adding a catalyst that promotes hydrolysis or condensation, the reaction can proceed even at a lower temperature. Furthermore, in the present invention, the heating condition and the humidity condition are selected so that the separation functional layer has pores, and the condensation reaction is appropriately performed.

  As a polymerization method of the ethylenically unsaturated group of the compound (A) having a silicon compound and the compound (B) having an ethylenically unsaturated group, heat treatment, electromagnetic wave irradiation, electron beam irradiation, and plasma irradiation can be performed. Here, the electromagnetic wave includes infrared rays, ultraviolet rays, X-rays, γ rays and the like. The polymerization method may be appropriately selected as appropriate, but polymerization by electromagnetic wave irradiation is preferred from the viewpoint of running cost, productivity and the like. Among electromagnetic waves, infrared irradiation and ultraviolet irradiation are more preferable from the viewpoint of simplicity. When the polymerization is actually performed using infrared rays or ultraviolet rays, these light sources do not need to selectively generate only light in this wavelength range, and any light source containing electromagnetic waves in these wavelength ranges may be used. However, from the viewpoint of ease of shortening the polymerization time and controlling the polymerization conditions, it is preferable that the intensity of these electromagnetic waves is higher than electromagnetic waves in other wavelength regions.

  Electromagnetic waves can be generated from halogen lamps, xenon lamps, UV lamps, excimer lamps, metal halide lamps, rare gas fluorescent lamps, mercury lamps, and the like. The energy of the electromagnetic wave is not particularly limited as long as it can be polymerized, but among them, high-efficiency, low-wavelength ultraviolet rays are excellent in thin film formation. Such ultraviolet rays can be generated by a low-pressure mercury lamp or an excimer laser lamp. The thickness and form of the separation functional layer according to the present invention may vary greatly depending on the respective polymerization conditions. If polymerization is performed using electromagnetic waves, the thickness and shape of the separation functional layers vary greatly depending on the wavelength of electromagnetic waves, the intensity, the distance to the irradiated object, and the processing time. Sometimes. Therefore, these conditions need to be optimized as appropriate.

  For the purpose of increasing the polymerization rate, it is preferable to add a polymerization initiator, a polymerization accelerator or the like during the formation of the separation functional layer. Here, the polymerization initiator and the polymerization accelerator are not particularly limited, and are appropriately selected according to the structure of the compound to be used, the polymerization technique, and the like.

  The polymerization initiator is exemplified below. As an initiator for polymerization by electromagnetic waves, benzoin ether, dialkylbenzyl ketal, dialkoxyacetophenone, acylphosphine oxide or bisacylphosphine oxide, α-diketone (for example, 9,10-phenanthrenequinone), diacetylquinone, furylquinone, anisylquinone, 4,4′-dichlorobenzylquinone and 4,4′-dialkoxybenzylquinone, and camphorquinone are exemplified. Initiators for thermal polymerization include azo compounds (eg, 2,2′-azobis (isobutyronitrile) (AIBN) or azobis- (4-cyanovaleric acid)), or peroxides (eg, peroxidation). Dibenzoyl, dilauroyl peroxide, tert-butyl peroctanoate, tert-butyl perbenzoate or di- (tert-butyl) peroxide), aromatic diazonium salts, bissulfonium salts, aromatic iodonium salts, aromatic sulfonium salts, Examples include potassium persulfate, ammonium persulfate, alkyl lithium, cumyl potassium, sodium naphthalene, and distyryl dianion. Of these, benzopinacol and 2,2'-dialkylbenzopinacol are particularly preferred as initiators for radical polymerization.

  Peroxides and α-diketones are preferably used in combination with aromatic amines to accelerate initiation. This combination is also called a redox system. Examples of such systems include benzoyl peroxide or camphorquinone and amines (eg, N, N-dimethyl-p-toluidine, N, N-dihydroxyethyl-p-toluidine, ethyl p-dimethyl-aminobenzoate). Ester or a derivative thereof). Furthermore, a system containing a peroxide in combination with ascorbic acid, barbiturate or sulfinic acid as a reducing agent is also preferred.

  Subsequently, when this is heat-processed at about 100-200 degreeC, a polycondensation reaction will occur and the separation membrane which concerns on this invention in which the separation functional layer derived from a silane coupling agent was formed in the porous support membrane surface can be obtained. Although the heating temperature depends on the material of the porous support membrane, if it is too high, dissolution occurs and the pores of the porous support membrane are blocked, resulting in a decrease in the amount of water produced in the composite semipermeable membrane. On the other hand, if it is too low, the polycondensation reaction becomes insufficient, and the removal rate decreases due to elution of the functional layer.

  In the above production method, the step of increasing the molecular weight of the silane coupling agent and the compound having one or more ethylenically unsaturated groups may be performed before the polycondensation step of the silane coupling agent, or after You can go. Moreover, you may carry out simultaneously.

  The composite semipermeable membrane thus obtained can be used as it is, but before use, it is preferable to hydrophilize the surface of the membrane with, for example, an alcohol-containing aqueous solution or an alkaline aqueous solution.

  The thickness of the separation functional layer is not limited, but is preferably 5 to 3000 nm in terms of separation performance and transmission performance. In particular, it is preferably 5 to 300 nm for reverse osmosis membranes, forward osmosis membranes, and nanofiltration membranes.

  The thickness of the separation functional layer can be based on the conventional method for measuring the thickness of the separation membrane. For example, after embedding the separation membrane with a resin, an ultrathin section is prepared, and after treatment such as staining, It can be measured by observing with a scanning electron microscope. As the main measurement method, when the separation functional layer has a pleat structure, measurement is performed at intervals of 50 nm in the cross-sectional length direction of the pleat structure located above the porous support membrane, and the number of pleats is measured at 20 pieces. It can be obtained from the average.

  When a porous support membrane is used in the present invention, it can be used as a membrane that supports the separation functional layer while maintaining the performance as a separation membrane.

  Although the material used for a porous support membrane and its shape are not specifically limited, For example, the film | membrane which formed the porous support body in the base material can be illustrated. As the material for the porous support, polysulfone, cellulose acetate, polyvinyl chloride, epoxy resin or a mixture and lamination of these materials is used, and the chemical, mechanical and thermal stability is high, and the pore size is controlled. It is preferable to use easy polysulfone.

  For example, a solution of the above polysulfone in N, N-dimethylformamide (hereinafter referred to as DMF) is cast on a substrate described later, for example, a densely woven polyester cloth or non-woven fabric, to a certain thickness, It can be manufactured by wet coagulation with.

  The porous support membrane used in the present invention is “Office of Saleen Water Research and Development Progress Report” No. 359 (1968), the polymer concentration, the solvent temperature, and the poor solvent can be adjusted to produce the above-described form. For example, a predetermined amount of polysulfone is dissolved in DMF to prepare a polysulfone resin solution having a predetermined concentration. Next, this polysulfone resin solution is applied to a substrate made of polyester cloth or nonwoven fabric to a substantially constant thickness, and after removing the surface solvent in the air for a certain period of time, the polysulfone is coagulated in the coagulation liquid. Can be obtained. At this time, DMF as a solvent is rapidly volatilized on the surface portion that comes into contact with the coagulation liquid, and polysulfone coagulates rapidly, and fine communication holes having the portion where DMF is present as a core are generated.

  Further, in the interior from the surface portion toward the base material, the volatilization of DMF and the solidification of polysulfone proceed more slowly than the surface, so that the DMF tends to aggregate and form large nuclei, and thus generate. The communication hole becomes larger in diameter. Of course, the above nucleation conditions gradually change depending on the distance from the film surface, so that a support film having a smooth pore size distribution without a clear boundary is formed. The present invention relates to the polysulfone resin solution used in this forming step, the temperature of the polysulfone resin solution, the concentration of polysulfone, the relative humidity of the atmosphere in which it is applied, the time from application to immersion in the coagulation liquid, the temperature and composition of the coagulation liquid, etc. By adjusting the ratio, it is possible to obtain a polysulfone membrane in which the average porosity and the average pore diameter are controlled.

  As long as the porous support membrane is one that gives mechanical strength to the separation membrane and does not have separation performance like a separation membrane for components having a small molecular size such as ions, the pore size and distribution are particularly Although it is not limited, for example, on the surface on the side where the separation functional layer is formed, which has uniform and fine holes, or gradually has a large fine hole from the surface on the side where the separation functional layer is formed to the other surface. A porous support membrane in which the projected area equivalent circle diameter of the pores measured from the surface using an atomic force microscope, an electron microscope or the like is 1 nm or more and 100 nm or less is preferably used. In particular, it preferably has a projected area equivalent circle diameter of 3 to 50 nm in terms of interfacial polymerization reactivity and retention of the separation functional membrane.

  The thickness of the porous support membrane is not particularly limited, but may be in the range of 20 to 500 μm in terms of the strength of the separation membrane, the difference in height of the separation membrane, and the morphological stability of the stock solution and permeate flow channels. Preferably, it is 30-300 micrometers.

  The form of the porous support membrane can be observed with a scanning electron microscope, a transmission electron microscope, or an atomic microscope. For example, when observing with a scanning electron microscope, the porous support is peeled off from the substrate, and then cut by a freeze cleaving method to obtain a sample for cross-sectional observation. The sample is thinly coated with platinum, platinum-palladium, or ruthenium tetrachloride, preferably ruthenium tetrachloride, and observed with a high-resolution field emission scanning electron microscope (UHR-FE-SEM) at an acceleration voltage of 3 to 6 kV. A Hitachi S-900 electron microscope or the like can be used as the high-resolution field emission scanning electron microscope. The film thickness of the porous support membrane and the projected area equivalent circle diameter are determined from the obtained electron micrograph. The thickness of the support membrane and the pore diameter are average values, and the thickness of the support membrane is an average value of 20 points measured by cross-sectional observation in a direction perpendicular to the thickness direction at intervals of 20 μm. The hole diameter is an average value of the diameters corresponding to the projected area circles by counting 200 holes.

  Furthermore, you may use a base material at the point of the intensity | strength of a separation membrane, dimensional stability, and uneven | corrugated formation ability. Although it does not specifically limit as a base material, A fibrous base material is used preferably at the point which gives moderate mechanical strength, maintaining the separation and permeation | permeation performance of a separation membrane, and controlling the height difference of the surface of a separation membrane.

  As the fibrous base material, polyolefin, polyester, cellulose and the like are used, and polyolefin and polyester are preferable from the viewpoint of forming a difference in height of the separation membrane and from the viewpoint of shape retention. Moreover, what mixed several raw materials can also be used as a base material.

  In the present invention, in order to form the spiral type separation membrane element 1 that does not require the telescope prevention plate 8 and has excellent long-term stability, as shown in FIG. 6 and FIG. In this case, it is essential that the resin 10 be disposed so that the projected area ratio is greater than 0 and less than 1 at least at one of the longitudinal ends of the perforated water collecting pipe 2 in the longitudinal direction. is there. In particular, the projected area ratio is preferably 0.005 or more and 0.6 or less, more preferably 0.01, in that the flow resistance of the stock solution is reduced and the flow path is stably formed while preventing the telescope phenomenon. It is 0.3 or less.

  The range to be applied may be either a band-shaped end on both sides in the longitudinal direction of the perforated water collecting tube 2 on the surface of the separation membrane unit 7 folded in an envelope shape or a band-shaped end on one side. The coating width, that is, the width of the belt-like end portion is preferably 10.0 mm or more and 100.0 mm or less from the end portion, and more preferably 5.0 mm or more and 70.0 mm or less.

  The arrangement pattern of the resin 10 arranged at the belt-like end portion may be continuous or discontinuous. The term “continuous” as used herein means a conventional one in which constituent materials are continuously formed when projected, such as a net or a film. On the other hand, discontinuous means having at least a discontinuous portion at the belt-like end portion, and means a material in which materials are discontinuously arranged, such as a dot shape or a stripe shape. The arrangement pattern is more preferably a dot shape or a stripe shape, and particularly preferably a dot shape. In the case of a dot shape, the height is preferably 0.1 mm or more and 2.0 mm or less, the diameter is 0.1 mm or more and 5.0 mm or less, and the interval is 0.2 mm or more and 20.0 mm or less. More preferably, the height is 0.2 mm or more and 1.0 mm or less, the diameter is 0.5 mm or more and 1.0 mm or less, and the interval is 1.0 mm or more and 15.0 mm or less.

  The resin 10 is preferably a thermoplastic resin such as polyolefin, modified polyolefin, polyester, polyamide, urethane, or epoxy resin, but from the viewpoint of processability and cost, polyolefin resin such as ethylene vinyl acetate copolymer resin or polyester resin is particularly preferable. More preferred, particularly preferred are polyolefin resins such as ethylene vinyl acetate copolymer resins and polyester resins that can be processed at 100 ° C. or lower.

  The application method of the resin 10 is not particularly limited as long as it is a method that can be arranged in a desired pattern on the strip-shaped end portion of the surface of the separation membrane unit 7, and examples thereof include a nozzle method, a screen method, and a gravure method.

  Although it does not specifically limit as a coating process of resin 10, It is a process of processing a support membrane in the stage before producing a separation membrane, a process of processing a laminated body which laminated a support membrane and a substrate, and a process of processing a separation membrane The method of apply | coating can be employ | adopted suitably.

  Here, the projected area ratio of the resin applied to the belt-shaped end portion means that the strip-shaped end portion portion of the separation membrane coated with the resin is cut out at 1 cm × 5 cm (5 cm at the end portion), and a commercially available microscope image analyzer is used. The projected area obtained when the resin is projected from the upper surface of the separation membrane can be obtained as a value obtained by dividing by the cut-out area.

  As the stock solution channel material 4 in the present invention, the projected area ratio on the surface of the separation membrane unit 7 (stock solution side) is 0.03 or more and 0.6 or less in terms of separation performance, permeation performance, and stock solution channel formation. A channel material made of a material is used. Here, the different material of the “continuous different material” means a material having a composition and a size different from the material used in the separation membrane. Accordingly, there is no particular limitation as long as it satisfies any of the composition, diameter, and shape different from any of the materials in the separation membrane having the separation functional layer, the porous support, and the base material as constituent components. Furthermore, the continuation of continuous different materials means a conventional material in which constituent materials are continuously formed when projected like a net or a film. The material of the different material is preferably polyolefin, modified polyolefin, polyester, polyamide, urethane, epoxy resin, etc., but is particularly limited as long as it is a different material excellent in the stock solution side flow path forming ability and satisfies the above projected area ratio. Not.

  Although it does not specifically limit as a formation method, In the case of a continuous shape, the method of laminating | stacking the channel material processed beforehand on the front side of a separation membrane is used.

  Here, the projected area ratio of the undiluted solution channel material is the undiluted undiluted solution channel material cut out at 5 cm × 5 cm and projected from the upper surface of the separation membrane using a commercially available microscope image analyzer. It can be obtained as a value obtained by dividing the projected area sometimes obtained by the cut-out area.

  As the permeate channel material 6 in the present invention, a channel material made of a different material having a projected area ratio of more than 0 and less than 1 is used on the rear surface of the separation membrane (permeate fluid side). In particular, the projected area ratio is preferably 0.1 or more and 0.8 or less, and more preferably 0.1 or more and 0.7 or less, in that the flow resistance of the permeate is reduced and the flow path is stably formed. .

  Here, the projected area ratio of the permeate channel material 6 is a 5 cm × 5 cm cut out permeate channel material made of a separation membrane and a different material, and a permeate channel material is obtained using a commercially available microscope image analyzer. It can be obtained as a value obtained by dividing the projected area obtained by projecting from the upper surface of the separation membrane by the cut-out area.

  The different material means a material having a composition and size different from the material used for the separation membrane. Therefore, if the separation functional layer, the porous support, and the base material are molded, and any difference in composition, diameter, and shape from any of the materials in the separation membrane when the height difference is given, it is particularly preferable. It is not limited. Furthermore, the different material may be continuous or discontinuous. The term “continuous” as used herein means a conventional one in which constituent materials are continuously formed when projected, such as a net or a film. On the other hand, the term “discontinuous” means that the leaf surface forming the element has at least a discontinuous portion, for example, a material in which the materials are discontinuously arranged, such as granular or linear. To do. The invention of the present application is characterized in that a different material excellent in formation of a permeate-side channel is arranged, and is not particularly limited as long as the projected area ratio is provided.

  By using the permeate flow channel material 6 using a different material, not only can the permeate flow channel be stably formed, but it is also possible to use a form and material different from the tricot which is a conventional knitted fabric. To do.

  For example, a net-like material having a coarse mesh, a rod shape, a columnar shape, a dot shape, a foamed material, a powdery material, a combination thereof, or the like can be used. Although it does not specifically limit as a composition, Polyolefin, copolymer polyolefin, etc., such as polyethylene and polypolypropylene, are preferable at a chemical-resistant point, and polymers, such as urethane and an epoxy, can also be used.

  The formation method is not particularly limited, but in the case of a continuous shape, a method of laminating previously processed flow path materials on the back side of the separation membrane is preferable, and in the case of a discontinuous shape, a different material is directly applied to the back side of the separation membrane. A method of arranging discontinuous materials such as hot melt dot processing, printing, and spraying is used.

  Next, the spiral separation membrane element of the present invention will be described.

  FIG. 5 is an end view of the spiral type separation membrane element of the present invention, and FIG. 6 is a development view before surrounding the spiral type separation membrane element of FIG.

  The spiral separation membrane element 1 of the present invention includes a folded separation membrane 5, a stock solution channel material 4, and a permeate flow on the outer peripheral surface of a water collection tube 2 composed of a perforated hollow tube having a plurality of water collection holes 3. A plurality of material groups made of the road material 6 are overlapped and wound, and further, as shown in FIGS. 5 and 6, the resin 10 is placed on the surface end portion (stock solution side) of the separation membrane 5. It is arranged in a band shape. A plurality of envelope-like separation membrane units 7 are bonded to each other with adhesive 9 made of a resin such as urethane resin or epoxy resin at both ends of each of the two separation membranes 5 that are back to back through the permeate passage material 6. Is formed. The inside of the envelope separation membrane unit 7 communicates with the inside of the water collecting pipe 2.

  Next, the manufacturing method of the spiral separation membrane element of the present invention will be described.

  The manufacturing method of the spiral separation membrane element of the present invention is not limited, but the polyamide separation functional layer is laminated on the porous support membrane and the base material, and after obtaining the separation membrane, the raw liquid flow passage material and the permeate flow passage material are arranged. A typical method for manufacturing the element will be described. It should be noted that the processing step for arranging the resin at the band-shaped end portion of the surface of the separation membrane can be incorporated before, during or after the separation membrane formation step as described above.

After combining the porous support membrane and the substrate, the polyfunctional amine aqueous solution is applied to the porous support membrane, the excess amine aqueous solution is removed with an air knife, etc., and then the polyfunctional acid halide-containing solution is applied, and the polyamide is applied. A separation functional layer is formed. Desirably, the organic solvent is immiscible with water, dissolves the polyfunctional acid halide, does not break the porous support membrane, and is inert to the polyfunctional amine compound and polyfunctional acid halide. Anything is acceptable. Preferred examples include hydrocarbon compounds such as n-hexane, n-octane, and n-decane. Furthermore, a separation membrane is obtained by performing chemical treatment such as chlorine, acid, alkali, and nitrous acid, washing treatment, and drying treatment to reduce the moisture of the separation membrane in order to improve separation performance and permeation performance as necessary. Subsequently, dots made of ethylene vinyl acetate copolymer resin having a diameter of 1 mmφ and a height of 400 μm are arranged in a staggered manner at intervals of 1 cm by hot-melt dot processing on the belt-like end portion of the sheet surface (stock solution side). Furthermore, using a conventional element manufacturing device, the net is placed on the stock solution side and the tricot is placed on the permeate side to produce a 4-inch element with 7 leaves and an effective leaf area of 9.1 m ^2. Is heated to the vicinity of the softening point of the ethylene-vinyl acetate copolymer resin with a radiation heater or the like, and the ends of the separation membrane on the stock solution side are fixed to each other by melting the resin. As an element manufacturing method, methods described in reference documents (Japanese Patent Publication No. 44-14216, Japanese Patent Publication No. 4-11928, Japanese Patent Application Laid-Open No. 11-226366) can be used.

  The separation membrane element of the present invention manufactured as described above can further be a separation membrane module connected in series or in parallel and housed in a pressure vessel.

  In addition, the separation membrane element and module described above can be combined with a pump that supplies fluid to them, a device that pretreats the fluid, and the like to form a fluid separation device. By using this separation device, for example, raw water can be separated into permeated water such as drinking water and concentrated water that has not permeated through the membrane, and water suitable for the purpose can be obtained.

  The higher the operating pressure of the fluid separator, the higher the removal rate, but the energy required for operation also increases, and considering the retention of the supply flow path and permeation flow path of the membrane element, the membrane module is covered. The operating pressure when passing through the treated water is preferably 0.2 MPa or more and 5 MPa or less. As the feed water temperature increases, the salt removal rate decreases, but as the supply water temperature decreases, the membrane permeation flux also decreases. Therefore, it is preferably 3 ° C. or more and 60 ° C. or less.

  The fluid to be treated by the membrane element according to the present invention is not particularly limited, but when used for water treatment, as raw water, 500 mg / L to 100 g / L TDS (Total Dissolved Solids: total seawater, brine, drainage, etc.) Liquid mixture containing dissolved solids). In general, TDS refers to the total dissolved solid content, and is expressed as “mass ÷ volume” or “weight ratio”. According to the definition, the solution filtered through a 0.45 micron filter can be calculated from the weight of the residue by evaporating at a temperature of 39.5 to 40.5 ° C., but more simply converted from practical salt (S) To do.

  The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples.

(Projected area ratio of resin applied to the strip-shaped end of the separation membrane surface)
The end of the separation membrane coated with resin was cut out at 1 cm × 5 cm (5 cm at the end), and the stage was moved using a laser microscope (selected from about 10 to 500 times magnification) to measure the total projected area. . A value obtained by dividing the projected area obtained by projecting from the coated resin film surface by the cut-out area was taken as the projected area ratio.

(Projected area ratio of undiluted solution channel material and permeate channel material)
Cut the undiluted solution channel material made of different materials from the separation membrane or the permeate channel material made of different materials at 5cm x 5cm, and move the stage using a laser microscope (select from 10 to 500 times magnification) The total projected area of the stock solution channel material or permeate channel material was measured. The projected area ratio was obtained by dividing the projected area obtained by projecting the stock solution channel material or the permeate channel material from the upper surface of the membrane or the back surface and dividing it by the area.

(Desalination rate (TDS removal rate))
The performance after 10 hours of operation (recovery rate 15%) was measured for 10 elements at 500 mg / L salt water, operating pressure of 0.75 MPa, operating temperature of 25 ° C. and pH of 7, respectively, and the average was obtained. It was.
TDS removal rate (%) = 100 × {1− (TDS concentration in permeated water / TDS concentration in feed water)}.

(Water production)
The performance after 10 hours of operation (recovery rate 15%) was measured for 10 elements at 500 mg / L salt water, operating pressure of 0.75 MPa, operating temperature of 25 ° C. and pH of 7, respectively, and the average was obtained. It was.

The amount of water permeated through the membrane element of the feed water (brine water) was expressed as the amount of water produced per cubic element (cubic meter) per day (m ³ / day).

(Telescope projection length)
Concentrated water outlet side of the spiral separation membrane element after 10 hours of operation (recovery rate 15%) for 10 elements at 500 mg / L salt water, operating pressure 0.75 MPa, operating temperature 25 ° C., pH 7 for 3 hours × 10 times The length of the film protruding from the end surface due to the telescope phenomenon was measured, and the average was obtained.

Example 1
On a non-woven fabric made of polyester fibers (yarn diameter: 1 dtex, thickness: about 98 μm, air permeability: 0.9 cc / cm ² / sec), 16.0% by weight of polysulfone and dimethylformamide (DMF) solution at a thickness of 180 μm A porous support membrane (thickness: 135 μm) roll made of a fiber-reinforced polysulfone support membrane was prepared by casting at room temperature (25 ° C.), immediately immersing in pure water, and allowing to stand for 5 minutes.

  Thereafter, the porous support membrane roll is unwound, and the polysulfone surface is coated with an aqueous solution of 1.8% by weight of m-PDA and 4.5% by weight of ε-caprolactam, and nitrogen is blown from an air nozzle to remove excess from the surface of the support membrane. After removing the aqueous solution, an n-hexane solution at 25 ° C. containing 0.06% by weight of trimesic acid chloride was applied so that the surface was completely wetted. After that, the excess solution is removed from the membrane by air blow, washed with hot water at 50 ° C., immersed in a 2% glycerin aqueous solution for 1 minute, treated in a hot air oven at 100 ° C. for 3 minutes, and semi-dried. A separation membrane roll was obtained.

Next, ethylene vinyl acetate copolymer resin (701A) is hot-melted, and a dot having a diameter of 1.0 mmφ and a height of 400 μm at intervals of 7.0 mm is formed on both sides of the separation membrane surface (stock solution side) end of the separation membrane roll. Was applied in a grid with a width of 50 mm. Thereafter, a tricot (thickness: 300 μm, groove width: 200 μm, ridge width: 300 μm, groove depth: 105 μm) is continuously laminated on the back side of the separation membrane as a permeate channel material, and is permeated from the separation membrane by folding cutting. Seven leaf-shaped separation membrane units on which the liquid flow path material was arranged were produced with a width of 930 mm so that the effective area of the separation membrane element was 9.1 m ² . Subsequently, nets (thickness: 900 μm, pitch: 3 mm × 3 mm) were alternately stacked as the separation membrane unit and the raw water side channel material.

Then, while winding the laminate of the separation membrane unit and the raw water side channel material around the water collecting pipe, a separation membrane element was produced by spirally winding seven leaf-like materials, and the film was wound around the outer periphery and fixed with tape. The end portion was heated at 120 ° C. for 1 minute, and edge cutting was further performed to produce a 4-inch element. The element was placed in a pressure vessel and operated for 3 hours × 10 times at a raw water of 500 mg / L sodium chloride, an operating pressure of 0.75 MPa, an operating temperature of 25 ° C., and a pH of 7 for a recovery rate of 14.8%. It was 3% and the amount of water produced was 10.4 m ³ / day, and no film jumping out by the telescope was observed.

(Examples 2 to 4)
In Example 2, the element was produced and evaluated in the same manner as in Example 1 except that the dot processing position was performed only on one end side, and the desalination rate was 99.4% and the amount of water produced was 10.1 m. ³ / day, and no deformation due to telescope was observed.

In Example 3, an element was fabricated and evaluated in the same manner as in Example 1 except that dots having a diameter of 1.0 mmφ and a height of 800 μm were applied with a width of 30 mm at intervals of 3.0 mm. The salt rate was 99.3%, the amount of water produced was 10.2 m ³ / day, and no film jumping out by a telescope was observed.

In Example 4, ethylene vinyl acetate copolymer resin (701D) was hot-melted on the back side of the sheet-like separation membrane as a permeate channel material, and dot processing with a diameter of 1.0 mmφ and a height of 150 μm was performed at 1.5 mm intervals. The element was produced and evaluated in the same manner as in Example 1. The salt removal rate was 99.2%, the amount of water produced was 10.3 m ³ / day, and no membrane jumping out by telescope was observed. .

(Comparative Example 1)
An element was prepared and evaluated in the same manner as in Example 1 except that the dot processing on the edge of the separation membrane surface and heating at 120 ° C. for 1 minute were not performed on the edge, and the salt removal rate was 96.9%. The amount of water produced was 10.1 m ³ / day, and the protruding length of the membrane by the telescope was 2.5 mm.

(Comparative Example 2)
An element was prepared and evaluated in the same manner as in Example 4 except that the dot processing on the edge of the separation membrane and heating at 120 ° C. for 1 minute were not performed on the edge, and the desalination rate was 96.3%. The amount of water produced was 9.9 m ³ / day, and the protruding length of the membrane by the telescope was 3.1 mm.

(Reference Example 1)
In Example 1, the dot processing on the edge part of the separation membrane and the heating of the edge part at 120 ° C. for 1 minute were not performed, the edge plate was attached after the edge cutting, the filament winding was performed, and the element was evaluated in the same manner. However, the desalination rate was 99.3% and the amount of water produced was 10.2 m ³ / day, and no membrane jumping out by the telescope was observed.

(Reference Example 2)
In Example 4, the dot processing on the edge of the separation membrane surface and heating of the edge at 120 ° C. for 1 minute were not performed, the edge plate was attached after edge cutting, filament winding was performed, and the elements were evaluated in the same manner. However, the desalination rate was 99.2%, the amount of water produced was 10.4 m ³ / day, and no membrane jumping out by the telescope was observed.

DESCRIPTION OF SYMBOLS 1 Spiral type separation membrane element 2 Water collecting pipe 3 Water collecting hole 4 Stock solution channel material 5 Separation membrane 6 Permeate channel material 7 Separation membrane unit 8 Telescope prevention plate 9 Adhesive 10 Resin 31 Stock solution 32 Permeate 33 Concentrated solution

Claims (4)

  Spiral-type separation in which a separation membrane unit with a permeate flow path material and a raw liquid flow path material are spirally wound around a perforated water collecting pipe in an enveloped membrane that is bonded by overlapping the separation membranes Resin so that the projected area ratio of at least one of the strip-like end portions on both sides in the longitudinal direction of the perforated water collecting pipe on the surface of the separation membrane unit is greater than 0 and less than 1 on the surface of the separation membrane unit Is a spiral separation membrane element.   The spiral separation membrane element according to claim 1, wherein the projected area ratio is 0.01 or more and 0.3 or less.   The spiral separation membrane element according to claim 1 or 2, wherein the resin pattern disposed on the belt-shaped end portion is dot-shaped.   A separation membrane unit having a permeate flow channel material in an envelope separation membrane bonded by overlapping the separation membranes, and a spiral type separation membrane that surrounds a raw liquid flow channel material in a spiral shape around a perforated water collecting pipe In the element manufacturing method, the projected area ratio of at least one of the strip-shaped end portions on both sides in the longitudinal direction of the perforated water collecting pipe on the surface of the separation membrane unit is more than 0 and less than 1 A method for producing a spiral separation membrane element, comprising disposing a resin on the substrate.