KR20220023961A - Separation membrane element and method of use thereof, and water treatment device - Google Patents

Abstract

In a spiral separation membrane element with a long supply-side flow path, even when the pressure loss of the supply fluid is large, deformation of the wound body or damage to the membrane surface is prevented, and operation with stable permeation performance and separation performance is achieved. A tube, a plurality of separation membranes having a supply-side surface and a permeation-side surface, a supply-side channel member, and a permeate-side channel member are provided, wherein the plurality of separation membranes have supply-side faces and permeate-side faces, respectively. They are disposed so as to overlap each other, the supply-side channel member is disposed between the supply-side surfaces of the separation membrane, the permeate-side channel member is disposed between the permeate-side faces of the separation membrane, and the supply-side end of the separation membrane A spiral type separation membrane element that satisfies predetermined requirements for the length of the opening on the negative side and the width of the closing member on the supply side and the transmission side of the separation membrane.

Description

Separation membrane element and method of use thereof, and water treatment device

The present invention relates to a separation membrane element, a method of using the same, and a water treatment device.

In the technology for removing ionic substances contained in seawater and brine, in recent years, as a process for saving energy and resources, the use of a separation method using a separation membrane element is expanding. The separation membrane used for the separation method using a separation membrane element is classified into a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane, a reverse osmosis membrane, and a forward osmosis membrane from the point of the pore diameter and a separation function. These membranes are used, for example, in the production of drinking water from seawater, brine, and water containing harmful substances, production of industrial ultrapure water, wastewater treatment and recovery of valuables, etc. built and used.

Although there are various forms as a separation membrane element, it is common in the point of supplying a supply fluid to one side of a separation membrane, and obtaining a permeate fluid from the other side. The separation membrane element is formed so that the effective membrane area per one separation membrane element becomes large, ie, the amount of the permeate|permeable fluid obtained per one separation membrane element increases so that by providing a bundled plurality of separation membranes. As a separation membrane element, various shapes, such as a spiral type, a hollow fiber type, a plate-and-frame type, a rotating flat membrane type, and a flat membrane integration type, are proposed according to a use and purpose.

For example, the spiral type separation membrane element shown as an example in FIG. 1 is widely used for reverse osmosis filtration. The spiral type separation membrane element 1 includes a perforated central tube 2 and a separation membrane unit wound around the perforated central tube 2 . The separation membrane unit includes a supply-side channel member 3 for supplying a supply fluid 101 (that is, a fluid to be treated) to the surface of the separation membrane, a separation membrane 4 for separating separation components contained in the supply fluid 101, and the separation membrane ( 4) It is formed by laminating the permeate-side channel member 5 for guiding the permeate fluid 102 separated from the supply fluid 101 to the perforated central pipe 2 by passing therethrough. The spiral type separation membrane element 1 is preferably used in that a large amount of permeated fluid can be taken out by applying pressure to the supply fluid.

And in recent years, in order to meet the request|requirement of further performance improvement of a spiral type separation membrane element, a plurality of techniques for changing the behavior of the fluid therein have been proposed (Patent Documents 1 to 3).

International Publication No. 2018/021387 International Publication No. 2017/019282 Specification of US Patent Application Publication No. 2012/0117878

However, in the spiral type separation membrane element in which the supply fluid is made high velocity as shown in the above patent document, since the pressure loss of the supply fluid is larger than that of a normal separation membrane element, telescoping in which the winding body is deformed easily occurs, and therefore the supply fluid There was a problem in that the separation performance was not sufficiently exhibited due to the occurrence of a short pass. In addition, when a high pressure is applied to the supply side, as shown in the partial cross-sectional schematic diagram of the separation membrane unit in FIG. 13 , depression of the membrane surface on the permeation side (a phenomenon in which the membrane surface is pressed toward the permeation side due to the pressure difference between the permeation side and the supply side) There was also a problem in that the deformation of the member closing the end portion, such as the supply-side closing member 6 , occurred, the film surface was damaged, and the separation performance was remarkably deteriorated.

Accordingly, an object of the present invention is to provide a separation membrane element capable of preventing deformation of a wound body or damage to a membrane surface even when a pressure loss of a supply fluid is large, and capable of operating while maintaining stable permeation performance and separation performance.

This invention for achieving the said objective is mainly provided with the following any structure.

(1) a perforated central tube, a plurality of separation membranes having a supply-side surface and a permeate-side surface, a supply-side channel member, and a permeate-side channel member;

The plurality of separation membranes are arranged so that the supply-side faces and the permeate-side faces are arranged to face each other and overlap each other, the supply-side channel member is disposed between the supply-side faces of the separation membrane, and the permeate-side channel member includes: It is disposed between the surfaces of the permeate side of the separation membrane, and the separation membrane, the supply-side channel member, and the permeate-side channel member are wound around the perforated center tube in the longitudinal direction of the separation membrane,

The surfaces on the supply side of the separation membrane include an end face A in the longitudinal direction of the perforated central pipe and an end face B on the opposite side thereof, and an outer peripheral end X and an inner periphery in a direction perpendicular to the longitudinal direction of the effective central pipe. Among the ends Y, the end face A is continuously closed by 60 to 95% from the end on the outer peripheral side, the end face B is continuously closed by 75 to 100% from the end on the inner peripheral side, and the inner peripheral end Y is closed has been made,

As for the surfaces on the permeation side of the separation membrane, only the inner peripheral end Y is open, and the outer peripheral end X and the end surfaces A and B are closed,

Let the lengths of the openings of the end face A and the end face B of the supply-side faces of the separation membrane be OL(A) and OL(B), respectively,

From the end face A and the end face B of the member for closing the end face A and the end face B of the permeate side faces of the separation membrane, the inner end in the longitudinal direction of the hole center pipe Let the distances of , respectively, be p(A) and p(B),

A member for closing the end face A and the end face B between the surfaces on the supply side of the separation membrane from the end face A and the end face B of the inner end in the longitudinal direction of the perforated central pipe. Let the distance be q(A) and q(B), respectively,

r(A) and r, respectively, the widths in the longitudinal direction of the part in contact with the separation membrane of the member for closing the end face A and the end face B of the surfaces on the supply side of the separation membrane If (B) is

p(A)≥q(A) is also p(B)≥q(B),

A separation membrane element that satisfies at least any of the requirements of (i) (ii) below.

(i) In the member for closing the end faces B of the supply-side faces of the separation membrane, from the inner circumferential side toward the outer circumferential side, r(B) of a portion having a length of at least OL(A) is 3 mm exist continuously.

(ii) In the member for closing the end faces A of the supply-side faces of the separation membrane, from the outer circumferential end toward the inner circumferential side, r(A) of a portion having a length of at least OL(B) is 3 mm exist continuously.

(2) supplying a supply fluid from an opening on the inner periphery of the supply-side surfaces of the separation membrane;

The method of using the separation membrane element according to (1) above, wherein the concentrated fluid is discharged from an opening on the outer periphery of the supply-side surfaces of the separation membrane.

(3) the separation membrane element according to (1) above;

a supply fluid supply unit connected to communicate with an opening on the inner periphery of the supply-side surfaces of the separation membrane to supply a supply fluid;

A water treatment apparatus having a concentrated fluid discharge unit connected to communicate with an opening on the outer peripheral side of the supply side surfaces of the separation membrane to discharge the concentrated fluid.

(4) the separation membrane element according to (1) above;

a supply fluid supply unit connected to communicate with an opening on the outer periphery of the supply-side surfaces of the separation membrane to supply a supply fluid;

A water treatment apparatus having a concentrated fluid discharge unit connected to communicate with an opening on an inner circumference side of the supply side surfaces of the separation membrane to discharge the concentrated fluid.

(5) a perforated central tube, a plurality of separation membranes having a supply-side surface and a permeate-side surface, a supply-side channel member, and a permeate-side channel member;

The plurality of separation membranes are arranged so that the surfaces on the supply side and the surfaces on the permeation side face each other and overlap each other, and are wound in the longitudinal direction thereof;

The supply-side channel member is disposed between the supply-side surfaces of the separation membrane,

The permeate-side channel member is disposed between the permeate-side surfaces of the separation membrane,

The surfaces on the supply side of the separation membrane are, among the end faces A and B in the longitudinal direction of the perforated central pipe, the end face A, and the outer peripheral end X in the direction perpendicular to the longitudinal direction of the effective central pipe, and Among the inner peripheral end portions Y, the outer peripheral end X is open 5% or more, and the end face B and the inner peripheral end Y are both closed,

As for the faces of the separation membrane on the permeation side, only the inner peripheral end Y is open, and the outer peripheral end X and the end surfaces A and B are closed,

From the end face A and the end face B of the member for closing the end face A and the end face B of the permeate side faces of the separation membrane, the inner end in the longitudinal direction of the hole center pipe Let the distances of , respectively, be p(A) and p(B),

A member for closing the end face A and the end face B between the surfaces on the supply side of the separation membrane from the end face A and the end face B of the inner end in the longitudinal direction of the perforated central pipe. Let the distance be q(A) and q(B), respectively,

r(A) and r, respectively, the widths in the longitudinal direction of the part in contact with the separation membrane of the member for closing the end face A and the end face B of the surfaces on the supply side of the separation membrane Referring to (B), a separation membrane element satisfying the following relationship.

p(A)>q(A), p(B)>q(B), and r(B)≥3 mm

According to the separation membrane element of the present invention, it is possible to prevent denting of the membrane surface toward the permeation side, deformation of the member closing the ends of a plurality of stacked separation membranes, and further damage to the membrane surface, and when the pressure loss of the supply fluid is large In addition, high recovery operation with increased fluid flow rate in the supply-side flow path is possible, and concentration polarization in the supply-side flow path is suppressed, thereby reducing the occurrence of fouling and scale, maintaining stable permeation performance and separation performance. can

1 is an exploded perspective view showing an example of a separation membrane element.
Fig. 2 is a schematic diagram (developed view of a separation membrane unit) showing an example of the structure of the separation membrane element of the present invention.
3 is a schematic diagram (expanded view) showing an example of a cross section of the separation membrane unit when the end face B on the supply side is closed by applying an adhesive from the outside after the separation membrane unit is wound.
4 is a schematic diagram (expanded view) showing an example of a cross section of a separation membrane unit when the end face B on the supply side is closed by applying an adhesive before the separation membrane unit is wound around.
5 is a schematic diagram showing an example of a state in which the separation membrane element of the present invention is loaded in a vessel.
6 is a schematic diagram showing an example of a state in which the separation membrane element of the present invention is loaded in a vessel.
Fig. 7 is a schematic diagram (developed view of a separation membrane unit) showing an example of a method of using the inverted L-shaped separation membrane element of the present invention ((a) supply side, (b) permeation side).
Fig. 8 is a schematic diagram (developed view of a separation membrane unit) showing an example of a method of using the L-shaped separation membrane element of the present invention ((a) supply side, (b) permeation side).
9 is a schematic diagram (a developed view of a separation membrane unit) showing an example of a method of using the inverted S-shaped separation membrane element of the present invention ((a) supply side, (b) permeation side).
Fig. 10 is a schematic diagram (developed view of a separation membrane unit) showing an example of a method of using the S-shaped separation membrane element of the present invention ((a) supply side, (b) permeation side).
11 is a schematic diagram (a developed view of a separation membrane unit) showing an example of a method of using the inverted SL type of the separation membrane element of the present invention ((a) supply side, (b) permeation side).
12 is a schematic diagram (expanded view of a separation membrane unit) showing an example of a method of using the separation membrane element of the present invention of the SL type ((a) supply side, (b) permeation side).
13 is a schematic diagram (partially developed cross-sectional view of a separation membrane unit) showing an example of dents in the membrane surface.

EMBODIMENT OF THE INVENTION Hereinafter, although embodiment of this invention is described in detail, referring drawings, this invention is not limited at all by these. In addition, in this specification, in demonstrating the schematic structure of the separation membrane element of this invention, although FIG. 1 is used, in the separation membrane element shown in FIG. 1, the flow path of the supply fluid and permeation fluid of each separation membrane unit in this invention. are not reflected, and they describe the details using FIGS. 2 to 12 .

The separation membrane element of the present invention, as shown in FIGS. 1 and 2, includes a perforated central tube 2, a plurality of separation membranes 4 having a supply side surface 10 and a permeation side surface 11; It is necessary to provide the supply-side channel member 3 and the permeate-side channel member 5 . In addition, the plurality of separation membranes 4 included in the separation membrane element 1A of the present invention are arranged so that the surfaces 10 on the supply side and the surfaces 11 on the transmission side face each other and overlap each other, and in Fig. 1 As an example is shown in the figure, it is wound in the longitudinal direction. In addition, in the present invention, for convenience of explanation, a state in which the supply-side channel member 3 or the permeate-side channel member 5 is sandwiched between the plurality of separation membranes 4 is referred to as a separation membrane unit.

(1) separator

As the separation membrane 4 included in the separation membrane element 1A of the present invention, a membrane having separation performance according to the usage method, purpose, and the like is used. The separation membrane 4 may be a single layer, or may be a composite membrane including a separation functional layer and a substrate from the viewpoint of strength or dimensional stability of the separation membrane 4 . Further, in the composite membrane, a porous support layer may be further provided between the separation functional layer and the substrate. Here, when the separation membrane 4 is a composite membrane, the surface provided with the separation functional layer is referred to as the supply side surface 10 , and the surface opposite to the surface including the separation functional layer is referred to as the permeation side surface 11 .

The separation functional layer may be a layer having both a separation function and a support function, and may have only a separation function. In addition, a "separation function layer" means a layer which has a separation function at least.

When the separation functional layer has both a separation function and a support function, the separation functional layer is preferably a layer containing, as a main component, a polymer selected from the group consisting of cellulose, polyvinylidene fluoride, polyethersulfone and polysulfone.

On the other hand, as the separation functional layer, a layer of a crosslinked polymer is preferable from the viewpoint of easy control of the pore diameter and excellent durability. Among them, a polyamide separation functional layer obtained by polycondensing a polyfunctional amine and a polyfunctional acid halide, an organic-inorganic hybrid functional layer, etc. are preferable from the viewpoint of excellent separation performance of the separation component in the feed fluid 101 . Do. These separation functional layers can be formed by polycondensing a monomer on the porous support layer.

The separation functional layer containing polyamide as a main component can be formed by interfacial polycondensation of a polyfunctional amine and a polyfunctional acid halide by a known method. For example, by applying a polyfunctional amine solution on the porous support layer, removing the excess polyfunctional amine solution with an air knife or the like, and then applying an organic solvent solution containing a polyfunctional acid halide, polycondensation This takes place to form a polyamide separation functional layer.

The material used for the porous support layer and the shape thereof are not particularly limited, and, for example, may be formed of a porous resin on the substrate. The porous support layer includes, for example, a layer of polysulfone, cellulose acetate, polyvinyl chloride, an epoxy resin, or a mixture thereof, or a layer formed by laminating these layers, but has high chemical, mechanical and thermal stability, and pore diameter A layer containing polysulfone, which is easy to control, is preferred.

The porous support layer containing polysulfone is formed by, for example, casting a N,N-dimethylformamide solution of polysulfone to a constant thickness on a substrate (eg, tightly woven polyester nonwoven fabric), and dissolving it in water. It can be formed by wet coagulation.

In addition, the porous support layer can be formed according to the method described in "Office of Sailin Water Research and Development Progress Report" No. 359 (1968). In addition, in order to obtain a desired form, a polymer concentration, the temperature of a solvent, or a poor solvent can be adjusted suitably.

As the base material of the separation membrane 4, it is preferable to use a fibrous base material from the viewpoint of strength or fluid permeability, and it is more preferable to use a long fiber nonwoven fabric or a short fiber nonwoven fabric.

In order to configure the separation membrane element of the present invention, the separation membrane 4 is formed in a rectangular shape. And the separation membrane 4 of such a shape is wound around the perforated central tube 2, as shown in FIG. The length in the winding direction of the separation membrane 4, that is, the length L in the longitudinal direction of the separation membrane 4, and the length W in the direction perpendicular to the longitudinal direction of the separation membrane 4 (that is, the perforated center tube 2) The larger the value of L/W, which is the ratio of the length in the longitudinal direction), the greater the flow rate when the supply fluid 101 passes through the separation membrane 4 is increased, so it is preferable from the viewpoint of suppressing concentration polarization. Specifically, it is preferable that the value of L/W is 2.5 or more. Moreover, it is preferable that the said length L is 750 mm or more.

(2) Supply side channel member

The supply-side flow path member 3 included in the separation membrane element 1A of the present invention is disposed to be sandwiched between the supply-side surfaces 10 of the separation membrane 4, and a flow path for supplying a supply fluid to the separation membrane 4 ( That is, a supply-side flow path) is formed. In order to suppress the concentration polarization of the supply fluid 101, the supply-side channel member 3 is preferably shaped to disturb the flow of the supply fluid 101 .

The supply-side channel member 3 may be a film, a net, or a member having a continuous shape in which convexities are provided on a sheet having voids, or exhibiting a projected area ratio greater than 0 and less than 1 with respect to the separation membrane 4, It does not matter even if it has a discontinuous shape. In addition, the supply-side channel member 3 may be separable from the separation membrane 4 , and may be fixed to the separation membrane 4 .

In addition, the material of the supply-side channel member 3 is not particularly limited, and the material may be the same as or different from that of the separation membrane 4 .

As for the supply-side flow path, it is important to stably form the flow path, but it is also important to reduce the pressure loss because the fluid passing therethrough is larger than that of the permeate-side flow path. Therefore, the projected area ratio of the supply-side channel member 3 to the separation membrane 4 is preferably 0.03 to 0.80, more preferably 0.05 to 0.50, and still more preferably 0.08 to 0.35.

The projected area ratio of the supply-side flow path member 3 to the separation membrane 4 can be calculated by analyzing an image taken with a microscope from the direction perpendicular to the supply-side flow path member 3 to the membrane surface.

When the thickness of the supply-side channel member 3 is excessively large, the effective membrane area per separation membrane element 1A becomes small. On the other hand, when the thickness of the supply-side flow passage material 3 is excessively small, the pressure loss in the supply-side flow passage increases, and the separation performance and permeation performance decrease. Therefore, 0.08-2.0 mm is preferable and, as for the thickness of the supply-side channel member 3, 0.20-1.00 mm is more preferable.

The thickness of the supply-side channel member 3 can be directly measured with a commercially available thickness measuring device.

(3) Permeate side channel member

The permeation-side channel member 5 included in the separation membrane element 1A of the present invention is disposed so as to be sandwiched between the permeation-side surfaces 11 of the separation membrane 4 and transmits the fluid that has passed through the separation membrane 4 . A flow path leading to the side outlet end face (that is, a permeation side flow path) is formed.

The permeate-side channel member 5 reduces the flow resistance of the permeate-side channel, and suppresses denting of the separation membrane 4 into the permeate fluid flow path even under pressure filtration, thereby stably forming the flow path. It is preferable that the area ratio is 0.3-0.75, and it is more preferable that it is 0.4-0.6. As the permeation-side channel member 5, for example, a conventional tricot, a weft knitted fabric with reduced fiber weight per unit area, a sheet in which projections are arranged on a porous sheet such as a nonwoven fabric, or a film or a nonwoven fabric is subjected to concavo-convex processing. One uneven processing sheet is mentioned.

Here, the cross-sectional area ratio of the permeation-side channel member will be described. When the permeate-side channel member is loaded into the separation membrane element, it is cut along the longitudinal direction of the water collecting pipe so as to pass through the convex portion of the permeate-side channel member, and the distance between the center of the convex portion and the center of the adjacent convex portion (also referred to as pitch) ) and the height of the permeate-side channel member, the ratio of the cross-sectional area of the permeate-side channel member between the center of the convex portion and the center of the adjacent convex portion to the product of the height of the permeate-side channel member is the cross-sectional area ratio. As a specific measuring method, as mentioned above, the permeation|transmission side channel member is cut|disconnected, and it can calculate using a microscope image analysis apparatus.

By disposing the permeate-side channel member 5 having the specific cross-sectional area ratio as described above in the separation membrane element 1A of the present invention, the flow resistance of the permeate-side channel can be further reduced. Concomitantly, in contrast to a separation membrane element including a flow path member having a large flow resistance, when operated at the same recovery rate, the flow rate of the supply fluid 101 is increased to reduce the concentration polarization, and in particular, the concentration polarization under high recovery rate operation. It is possible to further suppress the increase or the occurrence of scale.

If the thickness of the permeation-side channel member 5 is excessively large, the effective membrane area per separation membrane element 1A becomes small. On the other hand, if the thickness of the permeate-side channel member 5 is excessively small, the pressure loss in the permeate-side channel material increases. Therefore, 0.05 to 0.50 mm is preferable and, as for the thickness of the permeation-side channel member 5, 0.10 to 0.40 mm is more preferable.

The thickness of the permeation-side channel member 5 can be directly measured with a commercially available thickness measuring device.

The raw material of the permeate-side channel member 5 preferably has a compressive elastic modulus of 0.1 to 5.0 GPa in order to enable it to be easily wound in a spiral shape. As a raw material whose compressive modulus is 0.1-5.0 GPa, polyester, polyethylene, or polypropylene is mentioned, for example.

The compressive modulus of the permeation-side channel member 5 can be measured by performing a compression test using a precision universal testing machine and preparing a stress strain diagram.

(4) Membrane element

<Outline of Membrane Element>

The separation membrane element of the present invention is a spiral type separation membrane element capable of taking a long supply-side flow path. In this separation membrane element, the supply-side surfaces 10 of the separation membrane 4 are as illustrated in the separation membrane unit development of FIG. 2 . Similarly, among the end face A and the opposite end face B in the longitudinal direction of the perforated central pipe 2, the outer peripheral end X and the inner peripheral end Y in the direction perpendicular to the longitudinal direction of the perforated central pipe 2 , the end face A is continuously closed by 60 to 95% from the end on the outer peripheral side, the end face B is continuously closed by 75 to 100% from the end on the inner peripheral side, and the inner peripheral end Y is closed. That is, as for the surfaces 10 on the supply side of the separation membrane 4, the vicinity of the inner peripheral end of the end surface A is open, and the vicinity of the outer peripheral end and/or the outer peripheral end X of the end surface B are open. . On the other hand, as for the permeation|transmission side surfaces 11 of the said separation membrane 4, only the said inner peripheral edge part Y is open, and the other outer peripheral edge part X and the end surfaces A and B need to be closed. By adhering the plurality of overlapping separation membranes in this way, the flow of the supply fluid 101 can be made in the winding direction. Therefore, in particular, in the separation membrane element 1A, L/W, which is the ratio of the length L of the separation membrane 4 in the winding direction and the length W of the effective central tube 2 in the longitudinal direction, is 2.5 or more, in the separation membrane element 1A , it is possible to increase the flow rate of the supply fluid 101 with respect to the conventional separation membrane element 1 in which the supply fluid 101 flows in parallel to the perforated central pipe 2, and it is possible to make the element more resistant to fouling or scaling there is. Moreover, it is preferable that the inner peripheral edge part Y of the permeation|transmission side surfaces 11 comrades of the separation membrane 4 is open 90% or more from a viewpoint of pressure loss reduction.

5 and 6 are schematic diagrams showing an example of a state in which the separation membrane element 1A of the present invention is loaded in the vessel 23 . In the separation membrane element 1A in the embodiment shown in FIGS. 5 and 6 , a porous member 20 having a plurality of holes through which a fluid passes is also wound on the outer peripheral surface of the laminated and wound separation membrane unit. As the porous member 20, a net, a porous film, etc. are mentioned, for example.

5 and 6, the separation membrane element 1A and the vessel so that the feed fluid 101, the permeate fluid 102, and the concentrated fluid 103 do not mix in the vessel 23 A brine seal 22 is disposed in the gap at (23).

<Inverted L-Type Membrane Element>

The separation membrane element 1A of the present invention includes a plurality of types of separation membrane elements classified according to the flow direction of the supply fluid. One of them is an inverted L-type separator element. In one aspect of the bonding location of the separation membrane in the inverted L-type separation membrane element and the method of using the same, as shown in FIG. 7 (an exploded view of the separation membrane unit), the stage between the surfaces 10 on the supply side of the separation membrane 4 . The supply fluid 101 is supplied from the opening of the negative surface A, and the concentrated fluid 103 is discharged from the opening of the outer peripheral end X of the surfaces 10 on the supply side of the separation membrane 4 . The separation membrane element 1A to which this usage method is applied is referred to herein as an inverted L-type separation membrane element.

In the inverted L-type separation membrane element, in the supply-side surfaces 10 of the separation membrane 4, for example, the end surface A and the outer peripheral end X are open 5% or more, and the end surface B and the inner peripheral end It is preferable that all of Y are abolished. In addition, as for the permeation|transmission side surfaces 11 of the separation membrane 4, only the said inner peripheral edge part Y needs to be open, and the outer peripheral edge part X and the end surfaces A and B must all be closed. That is, in the inverted L-type separation membrane element, the end surfaces B of the supply-side surfaces 10 of the separation membrane 4 are completely closed. On the other hand, from the viewpoint of homogenizing the flow of the supply fluid 101 in the supply-side flow passage, the end surfaces A of the supply-side surfaces 10 of the separation membrane 4 have an open vicinity of the inner peripheral end, 5 to 40 % It is more preferable that it is open. In addition, the part (opening part) opened in the said end surface A is not limited to one place, You may divide into plurality. The said outer peripheral edge part X of the surfaces 10 comrades on the supply side of a separation membrane may make small the opening ratio in order to increase the flow velocity in the vicinity of the outlet of the concentrated fluid 103. Moreover, the opening part in the outer peripheral edge part X is also not limited to one place, You may divide into plurality, either. In the present invention, the opening ratio is the ratio of the length of the opening to the total length of the separation membrane 4 on the side of the separation membrane in which the opening is provided. The opening length OL(A) is the length from the inner peripheral end to the outer peripheral end of the opening as shown in Fig. 7, and when the openings are divided into a plurality of openings, from the inner peripheral end of the innermost opening to the outermost Let it be the length to the outer peripheral end of the opening part.

<L-Type Separator Element>

The separation membrane element 1A of the present invention also includes an L-type separation membrane element. In one aspect of the bonding location of the separation membrane in the L-type separation membrane element and the method of using the same, as shown in FIG. 8 (an exploded view of the separation membrane unit), the outer peripheral end of the supply-side surfaces 10 of the separation membrane 4 . The supply fluid 101 is supplied from the opening of X, and the concentrated fluid 103 is discharged from the opening of the end surface A of the supply-side surfaces 10 of the separation membrane 4 . The separation membrane element 1A to which this usage method is applied is referred to herein as an L-type separation membrane element.

In the L-type separation membrane element, as for the surfaces 10 on the supply side of the separation membrane 4, for example, the end surface A and the outer peripheral end X are open 5% or more, and the end surface B and the inner peripheral end It is preferable that all of Y are abolished. In addition, as for the permeation|transmission side surfaces 11 of the separation membrane 4, only the said inner peripheral edge part Y needs to be open, and the outer peripheral edge part X and the end surfaces A and B must all be closed. That is, in the L-type separation membrane element, the end surfaces B of the supply-side surfaces 10 of the separation membrane 4 are completely closed. In addition, the L-type separation membrane element uses the same bonding method as the inverted L-type separation membrane element, and since the concentrated fluid 103 is discharged from the end surfaces A of the surfaces 10 on the supply side of the separation membrane 4 , the step It is preferable that the aperture ratio in the vicinity of the inner peripheral end Y of the sub-surface A is smaller than that of the inverted L-type separation membrane element. Similarly, in order to supply the supply fluid 101 to the said outer peripheral edge part X of the surfaces 10 comrades on the supply side of the separation membrane 4, it is preferable that the opening ratio of the outer peripheral edge part X sets it as 90% or more. In addition, all of the opening parts in the said end surface A and the outer peripheral edge part X are not limited to one place, You may be divided into plurality. The opening length OL(A) is the length from the inner peripheral end to the outer peripheral end of the opening as shown in Fig. 8 .

<Reverse S-Type Membrane Element>

The separation membrane element 1A of the present invention also includes an inverted S-type separation membrane element. In one aspect of the bonding location of the separation membrane in the inverted S-type separation membrane element and the method for using the same, as shown in FIG. The supply fluid 101 is supplied from an opening in the vicinity of the inner periphery of the sub-surface A, and the concentrated fluid 103 is discharged from an opening in the vicinity of the outer periphery of the end surface B of the supply-side surfaces 10 of the separation membrane 4 . The separation membrane element 1A to which this method of use is applied is referred to herein as an inverted S-type separation membrane element.

In the inverted S-type separation membrane element, the outer peripheral end X of the supply-side surfaces 10 of the separation membrane 4 is completely closed. From the viewpoint of homogenizing the flow of the supply fluid 101 in the supply-side flow path, the end surface A to which the supply fluid 101 of the supply-side surfaces 10 of the separation membrane 4 is supplied is near the inner peripheral end Y. It is open, and it is more preferable that it is open 5 to 40%. In addition, the part (opening part) opened in the said end surface A is not limited to one place, You may divide into plurality. From the viewpoint of homogenizing the flow of the supply fluid 101 in the supply-side flow path, the end surface B, from which the concentrated fluid 103 between the supply-side surfaces 10 of the separation membrane 4 is discharged, is near the outer peripheral end X. It is open, and in order to increase the flow velocity in the vicinity of the outlet of the concentrated fluid 103, the opening ratio may be made smaller than that of the end face on the supply side. In addition, the opening part in the said end surface B is also not limited to one place, You may divide into plurality, either. The opening lengths OL(A) and OL(B) are the lengths from the inner peripheral end to the outer peripheral end of the opening as shown in Fig. 9, and when the openings are divided into plural in each end face, each end The negative surface WHEREIN: Let it be the length from the inner peripheral edge part of the opening part on the innermost peripheral side to the outer peripheral edge part of the opening part on the outermost peripheral side.

<S-Type Separator Element>

The separation membrane element 1A of the present invention also includes an S-type separation membrane element. In one aspect of the adhesion location of the separation membrane in the S-type separation membrane element and the method of using the same, as shown in FIG. The supply fluid 101 is supplied from the opening in the vicinity of the outer periphery of B, and the concentrated fluid 103 is discharged from the opening in the vicinity of the inner periphery of the end surface A of the supply-side surfaces 10 of the separation membrane 4 . The separation membrane element 1A to which this method of use is applied is referred to herein as an S-type separation membrane element.

In the S-type separation membrane element, the outer peripheral end X of the supply-side surfaces 10 of the separation membrane 4 is completely closed. The S-type separation membrane element uses the same bonding method as the inverted S-type separation membrane element, but a concentrated fluid 103 is transferred from an opening near the inner peripheral end Y of the end surface A of the supply-side surfaces 10 of the separation membrane 4 to each other. Therefore, it is preferable that the opening ratio in the vicinity of the inner peripheral end of the end face A is smaller than that of the inverted S-type separation membrane element. Similarly, since the supply fluid 101 is supplied, the opening in the vicinity of the outer peripheral end X of the end surfaces B of the supply-side surfaces 10 of the separation membrane 4 is preferably larger than the opening in the vicinity of the inner peripheral end Y. Moreover, all of the opening parts in the end surfaces A and B are not limited to one place, You may divide into plurality, and it is not cared about. The opening lengths OL(A) and OL(B) are the lengths from the inner peripheral end to the outer peripheral end of the opening as shown in FIG. The negative surface WHEREIN: Let it be the length from the inner peripheral edge part of the opening part on the innermost peripheral side to the outer peripheral edge part of the opening part on the outermost peripheral side.

<Reverse SL type separator element>

The separation membrane element 1A of the present invention also includes an inverted SL type separation membrane element. In one aspect of the adhesion location of the separation membrane in the inverted SL type separation membrane element and the method of using the same, as shown in FIG. The outer periphery end X of the supply-side faces 10 of the separation membrane 4 are open near the outer periphery of the sub-surface B, and the vicinity of the inner periphery of the end faces A of the supply-side faces 10 of the separation membrane 4 are open has been In this separation membrane element 1A, the method of using the supply fluid 101 from the opening in the end face A near the inner peripheral end Y is referred to as an inverted SL-type element. This separation membrane element has a form in which a separation membrane element in which an inverted S-type and an inverted L-type are combined, that is, the above-described inverted S-type separation membrane element and an inverted L-type separation membrane element are added. It does not limit about the opening position of the outer peripheral edge part X. The opening lengths OL(A) and OL(B) are the lengths from the inner peripheral end to the outer peripheral end of the opening as shown in FIG. 11 .

<SL type separator element>

The separation membrane element 1A of the present invention also includes an SL type separation membrane element. In one aspect of the adhesion location of the separation membrane in the SL type separation membrane element and the method of using the same, as shown in FIG. 12 (an exploded view of the separation membrane unit), the end surfaces of the supply-side surfaces 10 of the separation membrane 4 . In the vicinity of the outer periphery of B and between the surfaces 10 on the supply side of the separation membrane 4, the outer peripheral end X is opened, and the vicinity of the inner periphery of the end surface A between the surfaces 10 on the supply side of the separation membrane 4 is opened. there is. In this separation membrane element 1A, a method of supplying the supply fluid 101 from the openings of the outer peripheral end X and the end face B is referred to as an SL-type element. This separation membrane element is a separation membrane element in which an S-type and an L-type are combined, that is, the above-described S-type separation membrane element and the L-type separation membrane element are added. It does not limit about the opening position of the outer peripheral edge part X. The opening lengths OL(A) and OL(B) are the lengths from the inner peripheral end to the outer peripheral end of the opening as shown in FIG. 12 .

<Method of abolition of separation membrane, place of abolition>

In manufacturing the above-mentioned various separation membrane elements, as a method of closing the end faces A and B in the longitudinal direction of the perforated central tube 2 between the surfaces 10 on the supply side of the separation membrane 4, winding There is a case of doing it before and a method of doing it after wrapping. As a method performed before wrapping, adhesion|attachment by an adhesive agent, adhesion|attachment by a hot melt resin, and adhesion|attachment by an adhesive tape are mentioned. In the case of carrying out after wrapping, there may be mentioned a method of applying and bonding an adhesive from the outside.

Moreover, as shown in FIG. 1, you may attach the end plate 21 to the end face A and the end face B of the longitudinal direction of the perforated central tube 2 in order to prevent telescoping of a wound body. The end plate 21 mounted on the end face A needs to have a hole in order for the fluid to enter and exit. The end plate 21 attached to the end face B has a hole in it when fluid enters and exits from the end face B, and may or may not have a hole in the case where the fluid does not enter and exit from the end face B. . As a raw material of the end plate 21, ABS, polyvinyl chloride, polyethylene, or polypropylene is mentioned, for example.

As a method of closing the inner peripheral end Y or outer peripheral end X between the surfaces 10 on the supply side of the separation membrane 4, for example, adhesion with an adhesive, adhesion with a hot melt resin, adhesion with an adhesive tape, adhesion with a separation membrane ( The folding of 4) is mentioned.

On the other hand, as a method of closing the outer peripheral end X and the inner peripheral end Y in the direction perpendicular to the longitudinal direction of the perforated central tube 2 between the surfaces 11 on the permeation side of the separation membrane 4, for example, an adhesive Adhesion, the adhesion|attachment by a hot melt resin, the adhesion|attachment by an adhesive tape, etc. are mentioned.

As the supply-side closing member 6 and the transmission-side closing member 7 for closing the supply-side face 10 and the permeation-side face 11 each other, adhesive strength, hardening hardness, handling properties, etc. are taken into consideration. , it is preferable to use a urethane-based adhesive, or an epoxy-based adhesive. In addition, the viscosity of the adhesive before curing is preferably 4 to 15 Pa·s, and 5 to 12 Pa·s from the viewpoint of suppressing the generation of wrinkles when the separator 4 is wound while making the handling easy. more preferably.

As described above, by arranging the perforated central pipe 2, the separation membrane 4, the supply-side flow path member 3 and the permeation-side flow path member 5, and closing or opening the ends X and Y and the end faces A and B, the supply Since the flow of the fluid 101 can be made in the direction along the longitudinal direction of the separation membrane 4 , the supply fluid 101 can be made into a high velocity spiral type separation membrane element. However, simply by using the spiral type separation membrane element in which the supply fluid 101 is made into a high velocity by the above-described method, the pressure loss of the supply fluid 101 is larger than that of the normal separation membrane element 1, so that the wound body is deformed. Discarding telescoping tends to occur, and therefore a short pass of the supply fluid 101 occurs, and there is a problem in that the separation performance is not sufficiently exhibited. In addition, when a high pressure is applied to the supply-side flow path, the functional layer on the membrane surface is damaged due to dentation of the membrane surface on the permeation side due to the pressure of the film surface on the permeation side, or deformation of the member closing the end portion, causing damage and separation. There was also a problem in that the performance was significantly reduced.

On the other hand, in the present invention, as exemplified in the separation membrane unit cross-sectional views of FIGS. 3 and 4 (however, the end of the end face B side is shown in any of the drawings) and the developed views of the separation membrane unit of FIGS. 7 to 12, the separation membrane OL(A) and OL(B) are the lengths of the openings of the end faces A and B of the surfaces 10 on the supply side of the element 1A on the supply side of the separation membrane 4, respectively, and the permeation side of the separation membrane 4 The inner end of the permeate side closing member 7 for closing the end face A and the end face B of the faces 11 comrades in the longitudinal direction of the perforated central tube 2, the end face A and the end Let the distances from the negative surface B be p(A) and p(B), respectively, and the supply-side closing member 6 for closing the end surfaces A and B of the supply-side surfaces 10 of the separation membrane 4 . , the distance from the end face A and the end face B of the inner end in the longitudinal direction of the perforated central pipe 2 is q(A) and q(B), respectively, and the supply side of the separation membrane 4 is The width in the longitudinal direction of the perforated central tube 2 of the supply-side closing member 6 for closing the end faces A and the end faces B of the faces 10 comrades in contact with the separation membrane 4 is r ( A) and r(B), p(A)≥q(A) and p(B)≥q(B), and it shall satisfy at least any of the requirements of (i)(ii) below .

(i) In the supply-side closing member 6 for closing the end surfaces B of the supply-side surfaces 10 of the separation membrane 4, from the inner peripheral side toward the outer peripheral side, the length of at least OL(A) r(B) of the portion continuously exists by 3 mm or more.

(ii) in the supply-side closing member 6 for closing the end surfaces A of the supply-side surfaces 10 of the separation membrane 4, from the outer peripheral end toward the inner peripheral side, a length of at least OL(B) r(A) of the part exists continuously by 3 mm or more.

Here, p, q, and r are average values measured at intervals of 20 mm in the winding direction in a state in which the separation membrane unit is deployed, respectively. In addition, in the inner periphery and the outer periphery, the portion closest to the perforated central tube 2 in the state in which the separation membrane unit is deployed is referred to as the inner periphery, and the portion furthest from the perforated central tube 2 is referred to as the outer periphery.

In the present invention, by setting p(A)≥q(A) and p(B)≥q(B) over the entire area of the separation membrane 4 , the effective membrane portion of the supply-side surface 10 of the separation membrane 4 . Since the supply-side closing member 6 does not come into contact with each other, damage to the membrane surface can be prevented.

And, for example, as shown in FIGS. 7, 9 and 11, when the supply fluid is introduced from the opening of the length OL(A) provided at the inner peripheral end of the end face A, the end face B on the opposite side to the opening A load due to flow resistance is supported by the supply-side closing member 6 on the inner peripheral side. Further, for example, as shown in FIGS. 10 and 12 , when the supply fluid is introduced from an opening having a length OL(B) provided on the end surface B, the supply-side closing member ( 6) to support the load due to flow resistance. Further, for example, as shown in Fig. 8 , when the supply fluid flows in from the opening provided at the outer peripheral end X, a load is applied to the supply-side closing members 6 of both the end face A and the end face B by flow resistance. However, the portion of the supply-side closing member 6 on the opposite side to the end face A (that is, the end face B) where the opening is present is the weakest. And when the adhesion of the supply side closing member 6 is weak, the separation membrane element is deformed from that part. However, in the present invention, by satisfying at least one of (i) and (ii) above, the closing of the supply-side surfaces of the separation membrane can be made more robust, and even when a large flow resistance is applied to the separation membrane element 1A, It is possible to prevent deformation of the winding body.

In the case of the inverted L-type and L-type separation membrane elements, since the openings between the surfaces 10 on the supply side exist in the end surface A, it is necessary to satisfy the above (i). In the case of reverse S-type, S-type, reverse SL-type, and SL-type separation membrane elements, in particular, it is necessary to harden the end surface on the opposite side to the end surface on the side to which the supply fluid 101 is supplied with a high-pressure fluid. there is. That is, it is necessary to satisfy at least the above (i) in the case of the inverted S type and the inverse SL type, and at least the above (ii) in the case of the S type and the SL type.

Here, when an adhesive is applied and adhered from the outside after being wound around the end faces A and B of the supply-side faces of the separator, r(A) and r(B) in order to satisfy (i) and (ii) above. ) is 3 mm or more, it is preferable to press in the adhesive by applying pressure from the outside, or to perform an operation such as sucking the adhesive by suctioning it from the opposite end surface.

In addition, p(A) and p(B) of the surfaces 11 on the permeation side of the separation membrane 4 are preferably 5 to 30 mm in order to maintain strength while securing an effective membrane area as much as possible.

Regarding the ratio of p(B) and q(B), in order to narrow the supply-side flow path other than the effective membrane area and flow the supply fluid 101 at a higher flow rate, q(B)/p(B)≥0.5 it is preferable Also about the ratio of p(A) and q(A), for the same reason, it is preferable to set it as q(A)/p(A) >=0.5. q/p is the average value which measured the inside of an element at intervals of 20 mm.

In addition, if the coefficient of variation of r(A) or r(B) of 3 mm or more is 0.00 or more and 0.20 or less, it is possible to more uniformly support the load applied by the pressure loss, and r(A) or r(B) is Even in a situation close to 3 mm, deformation of the separator element can be prevented more reliably. The coefficient of variation is a value obtained by measuring r(A) or r(B) at intervals of 20 mm toward the winding direction, and dividing the standard deviation by the average value.

<Water treatment unit>

The separation membrane element 1A of this invention is applicable to water treatment apparatuses, such as an RO water purifier, for example. In the case of the inverted L-type, inverted S-type, and inverted SL-type separation membrane elements illustrated in Figs. 7, 9 and 11, the supply-side surfaces 10 of the separation membrane 4 are supplied from an opening on the inner periphery of the end surface A. It is connected to a water treatment device so as to supply the fluid 101 and discharge the concentrated fluid from the opening of the end face B or the outer peripheral end X or both of the surfaces 10 on the supply side of the separation membrane 4 . Therefore, the supply fluid supply part is connected so as to communicate with the openings on the inner periphery of the supply-side surfaces 10 of the separation membrane 4 (the opening on the inner periphery of the end face A), and the supply-side surfaces of the separation membrane 4 ( 10) A concentrated fluid discharge part is connected so that it may communicate with the opening part on the outer peripheral side (the said end surface B or the outer peripheral edge part X, or both openings).

On the other hand, in the case of an L-type, S-type, or SL-type separation membrane element, the supply fluid 101 is supplied from the end surface B or the outer peripheral end X or both openings between the surfaces 10 on the supply side of the separation membrane 4 . and the supply-side surfaces 10 of the separation membrane 4 are connected to a water treatment device so as to discharge the concentrated fluid 103 from the opening on the inner peripheral side of the end surfaces A. Therefore, the supply fluid supply part is connected so as to communicate with the openings on the outer periphery of the surfaces 10 on the supply side of the separation membrane 4 (the end face B or the outer periphery end X or both openings), and the separation membrane 4 The concentrated fluid discharge part is connected so that it may communicate with the opening part on the inner peripheral side (opening part on the inner peripheral side of the said end surface A) of the surfaces 10 on the supply side.

Example

The present invention will be described in more detail below by way of Examples, but the present invention is not limited by these Examples.

(p(A), p(B), q(A), q(B), r(A), r(B))

Measurements of p(A), p(B), q(A), q(B), r(A), and r(B) are performed in a state in which the separation membrane element is unwound and unfolded. It is measured using a nogis at intervals of 20 mm toward the winding direction, and an average value is calculated. In addition, when the separation membrane element is deployed, the separation membrane unit is unfolded while peeling the adhesive bonding the surfaces on the supply side of the separation membrane to each other.

(OL(A), OL(B))

Measurement of OL(A) and OL(B) is performed using a nozzle in a state in which the separation membrane element is unwound and the separation membrane element is deployed.

(Initial tidal flow rate and tidal flow rate decrease)

Tap water was used as the feed fluid. The concentrated water valve was opened at an operating pressure of 0.2 MPa, and a flushing operation was performed for 30 minutes. Thereafter, after operating for 60 minutes under the conditions of an operating pressure of 0.55 MPa and a temperature of 25°C, permeated water was sampled for 1 minute, and the initial fresh water amount (L/min) was measured. Thereafter, the amount of fresh water after the operation for 100 hours was similarly measured, and the rate of decrease in the amount of fresh water was calculated from the following equation.

Tidal flow rate decrease (%) = 100 x (1- (tidal flow rate after 100 hours of operation) / (initial tide volume))

(recovery rate)

In the measurement of the initial fresh water quantity, the ratio of the amount of supplied water supplied in 1 minute to the amount of permeated water was taken as the recovery rate.

(TDS removal rate)

The concentration of total dissolved solids (hereinafter referred to as "TDS") for the supplied water and the sampled permeate for sampling for 1 minute in the measurement of the initial fresh water amount were measured by electrical conductivity measurement, respectively, from the following formula The TDS removal rate was calculated.

TDS removal rate (%) = 100 x {1- (TDS concentration in permeate water / TDS concentration in feed water)}

(Example 1)

A 15.2 mass % N-dimethylformamide solution of polysulfone was applied to a thickness of 180 µm at room temperature on a nonwoven fabric containing polyethylene terephthalate fibers (yarn diameter: 1 decitex, thickness: about 0.09 mm, density: 0.80 g/cm 3 ). (25°C), immediately immersed in pure water, left for 5 minutes, and immersed in 80°C hot water for 1 minute, to prepare a porous support layer (thickness: 0.13 mm) including a fiber-reinforced polysulfone support layer.

After immersing the porous support layer in a 3.8% by mass aqueous solution of m-phenylenediamine for 2 minutes, it is pulled up slowly in the vertical direction, and nitrogen is sprayed from the air nozzle to remove the excess aqueous solution from the surface of the porous support layer, and then trimesic acid chloride The 0.175 mass % n-decane solution was apply|coated so that the surface might be fully wetted, and it left still for 1 minute, and also hold|maintained perpendicularly for 1 minute, and liquid-removed. Then, it wash|cleaned for 2 minutes in 90 degreeC hot water, and obtained the separation membrane.

The separation membrane thus obtained has a length L of 1200 mm in the winding direction of the separation membrane in the separation membrane unit when folded so that the fold line is the inner peripheral end Y and the supply side inside is 1200 mm, and the effective center tube 2 in the longitudinal direction It cut-processed multiple sheets so that the length W in this might be set to 250 mm. Then, on the cut separation membrane, a net (thickness: 0.5 mm, pitch: 3 mm × 3 mm) was arranged as a supply-side flow path material so that the inclination angle of the net construction yarn was 45° with respect to the winding direction.

As shown in FIG. 7 , the surfaces on the supply side of the separation membrane are continuously coated with a urethane adhesive from the outside to the inside in the winding direction so that the end surface A in the direction perpendicular to the longitudinal direction of the separation membrane is opened by 20%. did. The end surface B was continuously coated with a urethane adhesive so that the entire surface was closed. Then, the separation membrane was folded with the supply-side surface inside so that the inner peripheral end Y was the fold line. The urethane-based adhesive was continuously applied to the surfaces of the separation membrane on the permeation side so that the inner peripheral end was completely opened and the other end surfaces were completely closed. At this time, the adhesives on the permeation side of the end face A and the end face B were applied inside rather than the supply side so that p(A) > q(A) and p(B) > q(B).

The permeation-side channel member was prepared as follows using an applicator loaded with comb-shaped cores having a slit width of 0.5 mm and a pitch of 0.9 mm. That is, when the backup roll is temperature controlled at 20° C. and a separation membrane element is used, from the inner end to the outer end in the winding direction, in a straight line so as to be perpendicular to the longitudinal direction of the perforated central tube, high crystallinity PP (MFR 1000 g/10 min, melting point 161° C.) containing 40 mass% of a low crystalline α-olefin polymer (manufactured by Idemitsu Kosan Co., Ltd.; low stereoregularity polypropylene “L-MODU·S400” (trade name)) at 60 mass% The composition pellet was produced by apply|coating on the nonwoven fabric at the resin temperature of 205 degreeC, and running speed of 10 m/min. The nonwoven fabric had a thickness of 0.07 mm, a weight per unit area of 35 g/m 2 , and an embossed pattern (a circular shape with a diameter of 1 mm and a grid shape with a pitch of 5 mm).

The produced permeate-side channel member is cut and placed on the permeate-side surface of the separation membrane sandwiching the above-described supply channel member, and they are made of ABS (acrylonitrile-butadiene-styrene) perforated center tube (width: 300 mm, Diameter: 18 mm, 10 holes x 1 line in a straight line) was wound and wrapped in a spiral shape. A film having a hole was wound around the outer circumferential surface of the spiral-shaped separation membrane element. In addition, in this film, four holes with a width (longer diameter) and a height (shorter diameter) of 10 mm were formed at locations with a width of 200 mm in the center of the film in the width direction (corresponding to the circumferential direction of the separation membrane element). , four locations are provided in the height direction (corresponding to the longitudinal direction of the separation membrane element). After edge cuts were performed on both ends of the film-coated separation membrane element, a brine seal for separating the supply fluid and the concentrated fluid was attached to the outer peripheral surface to prepare a separation membrane element.

The average value of the adhesion width by each closing member in the obtained separation membrane element is p(A) = 20 mm, q(A) = 15 mm, p(B) = 20 mm, q(B) = 15 mm, r (B) = 15 mm.

And finally, in order to prevent a short pass of the fluid, an adhesive was applied around the outer periphery of the end face A and the end face B.

The separation membrane element was placed in a vessel, used as an inverted L-type, and each performance was evaluated with a recovery rate of 90%, and the results were as shown in Table 1.

(Examples 2 to 5)

By changing the application position and application amount of the adhesive for bonding the end surfaces A and B, p(A), q(A), p(B), q(B), r(A), r(B) ) was carried out in the same manner as in Example 1, except that the separation membrane and the separation membrane element were manufactured.

The separation membrane element was placed in a vessel, and each performance was evaluated under the same conditions as in Example 1, and the results are shown in Table 1.

(Examples 6 to 10)

By changing the adhesive application position and application amount for adhering the end face A and the end face B, p(A), q(A), p(B), q(B), r(A), r(B) A separation membrane and a separation membrane element were manufactured in the same manner as in Example 1 except that Table 2 was used.

The separation membrane element was placed in a vessel and each performance was evaluated under the same conditions as in Example 1 except that the use form was L-shaped, and the results are shown in Table 2.

(Example 11)

In the same manner as in Example 1, each member was prepared, and the separation membrane element was wound around in the same manner as in Example 1 except that an adhesive was not applied to the supply-side surface of the separation membrane before wrapping. An adhesive was applied from the outside to the end face B side in the longitudinal direction of the wrapped element, and the adhesive was sucked from the end face A side by a vacuum pump, and the adhesive was permeated to the inside of the supply-side flow path (in the longitudinal direction of the perforated central tube). On the end face A side of the surface on the supply side of the separation membrane, an adhesive was applied (suction was not performed) so that the opening ratio on the raw water side was 20%, thereby producing a separation membrane element.

The separation membrane element was put in a vessel, and each performance was evaluated under the same conditions as in Example 1, and the results are shown in Table 3.

(Example 12)

In the same manner as in Example 11, a separation membrane and a separation membrane element were manufactured.

Each performance was evaluated under the same conditions as in Example 1 except that the separation membrane element was placed in a vessel and the form of use was set to L, and the results are shown in Table 3.

(Example 13)

A separation membrane and a separation membrane element were manufactured in the same manner as in Example 1, except that the number of the winding pair of separation membranes and members was 3 and the winding diameter was 3 inches.

The separation membrane element was put in a vessel, and each performance was evaluated under the same conditions as in Example 1, and the results are shown in Table 3.

(Examples 14 to 16)

A separation membrane and a separation membrane element were manufactured in the same manner as in Example 1, except that the opening ratio of the opening of the end face A was shown in Table 3.

The separation membrane element was put in a vessel, and each performance was evaluated under the same conditions as in Example 1, and the results are shown in Table 3.

(Example 17)

A separation membrane and a separation membrane element were manufactured in the same manner as in Example 1, except that the membrane and the channel member were cut so that L and W were as shown in Table 4, and the number of the pair of membranes and the channel member to be wound was set to two.

The separation membrane element was put in a vessel, and each performance was evaluated under the same conditions as in Example 1, and the results are shown in Table 4.

(Example 18)

Regarding the surface on the supply side of the separation membrane, the opening width of the end surface B near the separation membrane element outer periphery is 200 mm, and the opening width of the outer peripheral end X is changed by changing the film wound around the outer peripheral surface to a non-permeable non-permeable one. Except having set it as 0 mm, it carried out all similarly to Example 1, and produced the separation membrane and the separation membrane element.

Each performance was evaluated under the same conditions as in Example 1 except that the separation membrane element was placed in a vessel and the use form was set to an inverted S-type, and the results are shown in Table 4.

(Example 19)

Regarding the supply side surface of the separation membrane, the opening width in the vicinity of the outer periphery of the separation membrane element of the end face B is 100 mm, and the urethane adhesive is applied so that the outer peripheral end X continuously opens 100 mm from the end face B side. In the same manner as in Example 1, a separation membrane and a separation membrane element were produced.

Each performance was evaluated under the same conditions as in Example 1 except that the separation membrane element was placed in a vessel and the use form was changed to a reverse SL type, and the results are shown in Table 4.

(Example 20)

In the same manner as in Example 1, each member was prepared, and the separation membrane element was wound around in the same manner as in Example 1 except that an adhesive was not applied to the supply-side surface of the separation membrane before wrapping. Next, a urethane-based adhesive is applied from the outside to a portion of the inner periphery of 20% of the end face B side in the longitudinal direction of the wrapped element, the 80% portion of the outer periphery of the end face B side is masked, and then from the end face A side by a vacuum pump. By suctioning, the adhesive was penetrated in the longitudinal direction of the perforated central tube. After that, a urethane-based adhesive is applied to a portion of the outer periphery of 80% of the end face B side (no suction is performed), and an adhesive is applied to the end face A side so that the opening on the end face A side becomes 20% continuously from the inside. It was applied (suction was not performed).

Each performance was evaluated under the same conditions as in Example 1 except that the separation membrane element was placed in a vessel and the use form was changed to an inverted L-type, and the results are shown in Table 4.

(Example 21)

It carried out similarly to Example 18, and produced the separation membrane element.

Each performance was evaluated under the same conditions as in Example 1 except that the separation membrane element was placed in a vessel and the use form was changed to an inverted S-type, and the results are shown in Table 5.

(Example 22)

Regarding the supply side surface of the separation membrane, the opening width in the vicinity of the separation membrane element outer periphery of the end face B is 100 mm, and a urethane adhesive is applied so that the outer peripheral end X continuously opens 100 mm from the end face A side. In the same manner as in Example 1, a separation membrane and a separation membrane element were produced.

Each performance was evaluated under the same conditions as in Example 1 except that the separation membrane element was placed in a vessel and the type of use was set to SL type, and the results are shown in Table 5.

(Comparative Example 1)

In the same manner as in Example 1, each member was prepared, and the separation membrane element was wound around in the same manner as in Example 1 except that an adhesive was not applied to the supply-side surface of the separation membrane before wrapping. An adhesive was applied from the outside to the end face B side in the longitudinal direction of the wound element. At this time, work such as suction or press-fitting was not performed. On the end face A side in the longitudinal direction, an adhesive was applied so that the opening ratio on the raw water side was 20%, and a separation membrane element was produced.

The separation membrane element was placed in a vessel, and each performance was evaluated under the same conditions as in Example 1, and the results are shown in Table 6. In this element, since no work such as suction or press-fitting was performed, it is considered that the separation membrane element deformed during the flushing operation due to the fact that r(B) is as small as 1 mm, resulting in a short pass.

(Comparative Example 2)

By changing the adhesive application position and application amount for adhering the end face A and the end face B, p(A), q(A), p(B), q(B), r(A), r(B) Except as shown in Table 6, all were carried out in the same manner as in Example 1, to manufacture a separation membrane and a separation membrane element.

The separation membrane element was placed in a vessel, and each performance was evaluated under the same conditions as in Example 1, and the results are shown in Table 6. In this element, when r(B) on the opposite side to the opening is as small as 2 mm, the separation membrane element is deformed during the flushing operation, and it is considered that a short pass occurred.

(Comparative Example 3)

By changing the adhesive application position and application amount for adhering the end face A and the end face B, p(A), q(A), p(B), q(B), r(A), r(B) Except as shown in Table 6, all were carried out in the same manner as in Example 1, to manufacture a separation membrane and a separation membrane element.

The separation membrane element was placed in a vessel, and each performance was evaluated under the same conditions as in Example 1, and the results are shown in Table 6. In this element, since q(A)/p(A) is 2 and the supply-side adhesive is caught on the effective membrane portion, it is considered that the membrane damage occurred during flushing.

(Comparative Example 4)

By changing the adhesive application position and application amount for adhering the end face A and the end face B, p(A), q(A), p(B), q(B), r(A), r(B) Except as shown in Table 6, all were carried out in the same manner as in Example 1, to manufacture a separation membrane and a separation membrane element.

The separation membrane element was placed in a vessel, and each performance was evaluated under the same conditions as in Example 1, and the results are shown in Table 6. In this element, since q(B)/p(B) is 2 and the supply-side adhesive is caught on the effective membrane portion, it is considered that the membrane damage occurred during flushing.

(Comparative Example 5)

By changing the adhesive application position and application amount for adhering the end face A and the end face B, p(A), q(A), p(B), q(B), r(A), r(B) Except as shown in Table 6, all were carried out in the same manner as in Example 1, to manufacture a separation membrane and a separation membrane element.

The separation membrane element was placed in a vessel, and each performance was evaluated under the same conditions as in Example 1, and the results are shown in Table 6. In this element, q(A)/p(A) and q(B)/p(B) are equal to 2, and since the supply-side adhesive is caught on the effective membrane portion, it is considered that the membrane surface is damaged during flushing.

(Comparative Example 6)

By changing the adhesive application position and application amount for adhering the end face A and the end face B, p(A), q(A), p(B), q(B), r(A), r(B) A separation membrane and a separation membrane element were manufactured in the same manner as in Example 1, except that Table 7 was used.

Each performance was evaluated under the same conditions as in Example 1 except that the separation membrane element was placed in a vessel and the method of use was set to L-type, and the results are shown in Table 7. In this element, q(A)/p(A) and q(B)/p(B) are equal to 2, and since the supply-side adhesive is caught on the effective membrane portion, it is considered that the membrane surface is damaged during flushing. When r(A) and r(B) on the side opposite to the opening are as small as 2 mm, it is considered that the separation membrane element is deformed during the flushing operation and a short pass has occurred.

(Comparative Example 7)

In the same manner as in Example 1, except that the outer peripheral surface of the spiral-shaped separation membrane element was covered with a liquid-tight film without bonding the surfaces on the supply side of the separation membrane to a general use mode (type I) as shown in FIG. 1 . Thus, a separation membrane and a separation membrane element were manufactured.

The separation membrane element was put in a vessel, and each performance was evaluated under the same conditions as in Example 1, and the results are shown in Table 7. This element is a normal I-type element, and since the flow rate on the supply side is slow with respect to the element of the present invention, it is considered that concentration polarization on the film surface occurred, and a decrease in the TDS removal rate and a decrease in the amount of fresh water due to scale generation were observed.

1: Separator element (Type I)
1A: separator element
2: Perforated center pipe
3: Supply-side flow path material
4: separator
5: Permeation side channel member
6: Absence of supply side closing
7: Permeation side closing member
10: the side of the supply side of the separation membrane
11: Permeation side surface of the separation membrane
20: porous member
21: end plate with hole
22: brine seal
23: Vessel
101: supply fluid
102: permeate fluid
103: concentrated fluid
A, B: End faces in the longitudinal direction of the perforated central pipe
X: the outer peripheral end in the direction perpendicular to the longitudinal direction of the perforated central tube
Y: the inner peripheral end in the direction perpendicular to the longitudinal direction of the perforated central tube
L: the length of the supply-side flow path (the length of the separation membrane in the direction perpendicular to the longitudinal direction of the perforated central pipe)
W: Width of the supply-side flow path (length of the separation membrane in the longitudinal direction of the perforated central pipe)
OL: the length of the opening of the end face A and the end face B between the faces on the supply side of the separation membrane

Claims (12)

A perforated central tube, a plurality of separation membranes having a supply-side surface and a permeate-side surface, a supply-side channel member, and a permeate-side channel member are provided;
The plurality of separation membranes are arranged so that the supply-side faces and the permeate-side faces are arranged to face each other and overlap each other, the supply-side channel member is disposed between the supply-side faces of the separation membrane, and the permeate-side channel member includes: It is disposed between the surfaces of the permeate side of the separation membrane, and the separation membrane, the supply-side channel member, and the permeate-side channel member are wound around the perforated center tube in the longitudinal direction of the separation membrane,
The surfaces on the supply side of the separation membrane include an end face A in the longitudinal direction of the perforated central pipe and an end face B on the opposite side thereof, and an outer peripheral end X and an inner periphery in a direction perpendicular to the longitudinal direction of the effective central pipe. Among the ends Y, the end face A is continuously closed by 60 to 95% from the end on the outer peripheral side, the end face B is continuously closed by 75 to 100% from the end on the inner peripheral side, and the inner peripheral end Y is closed has been made,
As for the surfaces on the permeation side of the separation membrane, only the inner peripheral end Y is open, and the outer peripheral end X and the end surfaces A and B are closed,
Let the lengths of the openings of the end face A and the end face B of the supply-side faces of the separation membrane be OL(A) and OL(B), respectively,
From the end face A and the end face B of the member for closing the end face A and the end face B of the permeate side faces of the separation membrane, the inner end in the longitudinal direction of the hole center pipe Let the distances of , respectively, be p(A) and p(B),
A member for closing the end face A and the end face B between the surfaces on the supply side of the separation membrane from the end face A and the end face B of the inner end in the longitudinal direction of the perforated central pipe. Let the distance be q(A) and q(B), respectively,
r(A) and r, respectively, the widths in the longitudinal direction of the part in contact with the separation membrane of the member for closing the end face A and the end face B of the surfaces on the supply side of the separation membrane If (B) is
p(A)≥q(A) is also p(B)≥q(B),
A separation membrane element that satisfies at least any of the requirements of (i) (ii) below.
(i) In the member for closing the end faces B of the supply-side faces of the separation membrane, from the inner circumferential side toward the outer circumferential side, r(B) of a portion having a length of at least OL(A) is 3 mm exist continuously.
(ii) In the member for closing the end faces A of the supply-side faces of the separation membrane, from the outer circumferential end toward the inner circumferential side, r(A) of a portion having a length of at least OL(B) is 3 mm exist continuously. The separation membrane element according to claim 1, wherein the coefficient of variation of r(A) or r(B) is 0.00 or more and 0.20 or less. The separation membrane element according to claim 1 or 2, wherein as for the surfaces on the supply side of the separation membrane, 100% of the end faces B are closed and the outer peripheral end X is open 5% or more. The separation membrane element according to any one of claims 1 to 3, wherein the member for closing the end face A and the end face B of the surfaces on the supply side is a urethane-based adhesive or an epoxy-based adhesive. The method according to any one of claims 1 to 4, wherein the separation membrane has a ratio L/W of a length L in a longitudinal direction of the separation membrane to a length W in a direction perpendicular to the longitudinal direction of the separation membrane , 2.5 or greater, a separator element. The separation membrane element according to any one of claims 1 to 5, wherein for p(B) and q(B), q(B)/p(B)≥0.5. The separation membrane element according to any one of claims 1 to 6, wherein for p(A) and q(A), q(A)/p(A)≥0.5. supplying a supply fluid from an opening on the inner periphery of the supply-side surfaces of the separation membrane;
The method of using the separation membrane element according to any one of claims 1 to 7, wherein the concentrated fluid is discharged from an opening on the outer periphery of the supply-side surfaces of the separation membrane. supplying a supply fluid from an opening on the outer periphery of the supply-side surfaces of the separation membrane;
The method of using the separation membrane element according to any one of claims 1 to 7, wherein the concentrated fluid is discharged from an opening on the inner periphery of the supply-side surfaces of the separation membrane. The separation membrane element according to any one of claims 1 to 7,
a supply fluid supply unit connected to communicate with an opening on the inner periphery of the supply-side surfaces of the separation membrane to supply a supply fluid;
A water treatment apparatus having a concentrated fluid discharge unit connected to communicate with an opening on the outer peripheral side of the supply side surfaces of the separation membrane to discharge the concentrated fluid. The separation membrane element according to any one of claims 1 to 7,
a supply fluid supply unit connected to communicate with an opening on the outer periphery of the supply-side surfaces of the separation membrane to supply a supply fluid;
A water treatment apparatus having a concentrated fluid discharge unit connected to communicate with an opening on an inner circumference side of the supply side surfaces of the separation membrane to discharge the concentrated fluid. A perforated central tube, a plurality of separation membranes having a supply-side surface and a permeate-side surface, a supply-side channel member, and a permeate-side channel member are provided;
The plurality of separation membranes are arranged so that the surfaces on the supply side and the surfaces on the permeation side face each other and overlap each other, and are wound in the longitudinal direction thereof;
The supply-side channel member is disposed between the supply-side surfaces of the separation membrane,
The permeate-side channel member is disposed between the permeate-side surfaces of the separation membrane,
The surfaces on the supply side of the separation membrane are, among the end faces A and B in the longitudinal direction of the perforated central pipe, the end face A, and the outer peripheral end X in the direction perpendicular to the longitudinal direction of the effective central pipe, and Among the inner peripheral end portions Y, the outer peripheral end X is open 5% or more, and the end face B and the inner peripheral end Y are both closed,
As for the faces of the separation membrane on the permeation side, only the inner peripheral end Y is open, and the outer peripheral end X and the end surfaces A and B are closed,
From the end face A and the end face B of the member for closing the end face A and the end face B of the permeate side faces of the separation membrane, the inner end in the longitudinal direction of the hole center pipe Let the distances of , respectively, be p(A) and p(B),
A member for closing the end face A and the end face B between the surfaces on the supply side of the separation membrane from the end face A and the end face B of the inner end in the longitudinal direction of the perforated central pipe. Let the distance be q(A) and q(B), respectively,
r(A) and r, respectively, the widths in the longitudinal direction of the part in contact with the separation membrane of the member for closing the end face A and the end face B of the surfaces on the supply side of the separation membrane Referring to (B), a separation membrane element satisfying the following relationship.
p(A)>q(A), p(B)>q(B), and r(B)≥3 mm

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