JP6973650B2 - Separation membrane element and its usage, as well as water treatment equipment - Google Patents

Description

The present invention relates to a separation membrane element and its usage, and a water treatment apparatus.

In the technique for removing ionic substances contained in seawater and brackish water, the use of the separation method using a separation membrane element has been expanding in recent years as a process for energy saving and resource saving. Separation membranes used in the separation membrane element separation method are classified into microfiltration membranes, ultrafiltration membranes, nanofiltration membranes, reverse osmosis membranes, and forward osmosis membranes in terms of their pore size and separation function. These films are used, for example, for the production of drinking water from seawater, brackish water, water containing harmful substances, industrial ultrapure water, wastewater treatment, recovery of valuable resources, and the like. It is used properly according to the separation component and separation performance.

There are various forms of the separation membrane element, but they are common in that the supply fluid is supplied to one surface of the separation membrane and the permeation fluid is obtained from the other surface. The separation membrane element includes a plurality of bundled separation membranes so that the effective membrane area per separation membrane element is large, that is, the amount of permeable fluid obtained per separation membrane element is large. It is formed to increase. As the separation membrane element, various shapes such as a spiral type, a hollow fiber type, a plate and frame type, a rotary flat membrane type, and a flat membrane integrated type have been proposed according to the application and purpose.

For example, for reverse osmosis filtration, a spiral separation membrane element as shown in FIG. 1 is widely used. 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 permeates the supply side flow path material 3 that supplies the supply fluid 101 (that is, the fluid to be processed) to the surface of the separation membrane, the separation membrane 4 that separates the separation components contained in the supply fluid 101, and the separation membrane 4. It is formed by laminating a permeation side flow path material 5 for guiding the permeation fluid 102 separated from the supply fluid 101 to the perforated center tube 2. The spiral type separation membrane element 1 is preferably used because a large amount of permeated fluid can be taken out by applying pressure to the supply fluid.

In recent years, in order to meet the demand for higher performance of the spiral separation membrane element, a plurality of techniques for changing the behavior of the fluid inside the element have been proposed (Patent Documents 1 to 3).

International Publication No. 2018/021387 International Publication No. 2017/019282 U.S. Patent Application Publication No. 2012/01/17878

However, in the spiral type separation membrane element in which the flow velocity of the supply fluid is increased as shown in the above patent document, the pressure loss of the supply fluid is larger than that of the normal separation membrane element, so that the winding body is deformed. There is a problem that terrescorping is likely to occur, which causes a short path of the supply fluid and the separation performance is not sufficiently exhibited. Further, when a high pressure is applied to the supply side, the membrane surface drops to the permeation side (due to the pressure difference between the permeation side and the supply side to the permeation side) as shown in the schematic cross-sectional view of the separation membrane unit in FIG. There is also a problem that the film surface is pressed) or the member that closes the end portion such as the supply side closing member 6 is deformed, the film surface is damaged, and the separation performance is significantly deteriorated.

Therefore, the present invention prevents deformation of the winding body and damage to the membrane surface even when the pressure loss of the supply fluid is large, and enables operation while achieving both stable permeation performance and separation performance. It is intended to provide a membrane element.

The present invention for achieving the above object mainly comprises any of the following configurations.
(1) A perforated central canal, a plurality of separation membranes having a supply-side surface and a permeation-side surface, a supply-side flow path material, and a permeation-side flow path material are provided.
The plurality of separation membranes are arranged and stacked so that the surfaces on the supply side and the surfaces on the transmission side face each other, and the supply side flow path material is between the surfaces on the supply side of the separation membrane. The permeation side flow path material is arranged between the permeation side surfaces of the separation membrane, and the separation membrane, the supply side flow path material, and the permeation side are arranged around the perforated center tube. The flow path material is wound in the longitudinal direction of the separation membrane, and is formed.
The supply-side surfaces of the separation membrane are the end surface A in the longitudinal direction of the perforated central canal and the end surface B on the opposite side thereof, and the outer peripheral end portion X and the inside in the direction perpendicular to the longitudinal direction of the effective central canal. Among the peripheral end portions Y, the end surface A is continuously closed by 60 to 95% from the outer peripheral end, and the end surface B is continuously closed by 75 to 100% from the inner peripheral end. The inner peripheral end portion Y is closed, and only the inner peripheral end portion Y is open between the surfaces on the transmission side of the separation membrane, and the outer peripheral end portion X and the end surfaces A and B are closed. Ori,
The lengths of the openings of the end faces A and the end faces B between the supply-side surfaces of the separation membrane are set to OL (A) and OL (B), respectively.
The distance from the end surface A and the end surface B of the inner end of the member for closing the end surface A and the end surface B between the permeation side surfaces of the separation membrane in the longitudinal direction of the perforated central canal. , P (A) and p (B), respectively.
The distance from the end surface A and the end surface B of the inner end of the member for closing the end surface A and the end surface B between the supply-side surfaces of the separation membrane in the longitudinal direction of the perforated central canal. , Q (A) and q (B), respectively.
The width in the longitudinal direction of the perforated central canal of the portion of the member for closing the end surface A and the end surface B of the supply-side surfaces of the separation membrane in contact with the separation membrane is r ( If A) and r (B),
p (A) ≧ q (A) and p (B) ≧ q (B),
A separation membrane element that meets at least one of the following requirements (i) and (ii).
(I) In the member for closing the end faces B between the supply-side surfaces of the separation membrane, r (a portion having a length of at least OL (A) or more from the inner peripheral end to the outer peripheral side). B) exists continuously for 3 mm or more.
(Ii) In the member for closing the end faces A between the supply-side surfaces of the separation membrane, r (i) of a portion having a length of at least OL (B) or more from the outer peripheral end to the inner peripheral side. A) exists continuously for 3 mm or more.
(2) The supply fluid is supplied from the opening on the inner peripheral side between the supply-side surfaces of the separation membrane, and the supply fluid is supplied.
The method of using the separation membrane element according to (1) above, wherein the concentrated fluid is discharged from the openings on the outer peripheral side of the surfaces on the supply side of the separation membrane.
(3) With the separation membrane element described in (1) above,
A supply fluid supply unit that is connected so as to communicate with an opening on the inner peripheral side of the supply side surfaces of the separation membrane and supplies the supply fluid.
A water treatment apparatus having a concentrated fluid discharging portion connected so as to communicate with an opening on the outer peripheral side between the supply-side surfaces of the separation membrane and discharging the concentrated fluid.
(4) With the separation membrane element described in (1) above,
A supply fluid supply unit that is connected so as to communicate with an opening on the outer peripheral side of the supply side surfaces of the separation membrane and supplies the supply fluid.
A water treatment device having a concentrated fluid discharge unit that is connected so as to communicate with an opening on the inner peripheral side of the supply-side surfaces of the separation membrane and discharges the concentrated fluid.
(5) A perforated central canal, a plurality of separation membranes having a supply-side surface and a permeation-side surface, a supply-side flow path material, and a permeation-side flow path material are provided.
The plurality of separation membranes are arranged and stacked so that the surfaces on the supply side and the surfaces on the transmission side face each other, and are wound in the longitudinal direction thereof.
The supply-side flow path material is arranged between the supply-side surfaces of the separation membrane.
The permeation-side flow path material is arranged between the permeation-side surfaces of the separation membrane.
The surfaces on the supply side of the separation membrane are the end surface A in the longitudinal direction of the perforated central canal, the end surface A in the end surface B, and the outer peripheral end portion X in the direction perpendicular to the longitudinal direction of the effective central canal. And the outer peripheral end portion X in the inner peripheral end portion Y is opened by 5% or more, and the end surface B and the inner peripheral end portion Y are both closed.
Only the inner peripheral end portion Y is open between the surfaces on the transmission side of the separation membrane, and the outer peripheral end portion X and the end surfaces A and B are closed.
The distance from the end surface A and the end surface B of the inner end of the member for closing the end surface A and the end surface B between the permeation side surfaces of the separation membrane in the longitudinal direction of the perforated central canal. , P (A) and p (B), respectively.
The distance from the end surface A and the end surface B of the inner end of the member for closing the end surface A and the end surface B between the supply-side surfaces of the separation membrane in the longitudinal direction of the perforated central canal. , Q (A) and q (B), respectively.
The width in the longitudinal direction of the perforated central canal of the portion of the member for closing the end surface A and the end surface B of the supply-side surfaces of the separation membrane in contact with the separation membrane is r ( A) and r (B) are separation membrane elements that satisfy the following relationships.

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 the membrane surface from falling to the permeation side, deformation of the member that closes the ends of the plurality of laminated separation membranes, and further damage to the membrane surface. Even when the pressure loss of the supply fluid is large, high recovery rate operation with increased fluid flow velocity in the supply side flow path is possible, and concentration polarization in the supply side flow path is suppressed. , Fouling and scale generation are reduced, and stable permeation performance and separation performance can be maintained.

It is an exploded perspective view which shows an example of a separation membrane element. It is a schematic diagram (development view of the separation membrane unit) which shows an example of the structure of the separation membrane element of this invention. It is a schematic diagram (developed view) which shows an example of the cross section of a separation membrane unit in the case where the end face B on the supply side is closed by applying an adhesive from the outside after surrounding the separation membrane unit. It is a schematic diagram (developed view) which shows an example of the cross section of a separation membrane unit when the end face B on the supply side is closed by applying an adhesive before surrounding the separation membrane unit. It is a schematic diagram which shows an example of the state which the separation membrane element of this invention is loaded in the vessel. It is a schematic diagram which shows an example of the state which the separation membrane element of this invention is loaded in the vessel. It is a schematic diagram (development view of the separation membrane unit) which shows an example of the use method of the inverted L type of the separation membrane element of this invention ((a) supply side, (b) transmission side). It is a schematic diagram (development view of the separation membrane unit) which shows an example of the L-shaped use method of the separation membrane element of this invention ((a) supply side, (b) transmission side). It is a schematic diagram (development view of the separation membrane unit) which shows an example of the use method of the inverted S type of the separation membrane element of this invention ((a) supply side, (b) transmission side). It is a schematic diagram (development view of the separation membrane unit) which shows an example of the S type use method of the separation membrane element of this invention ((a) supply side, (b) transmission side). It is a schematic diagram (development view of the separation membrane unit) which shows an example of the use method of the inverted SL type of the separation membrane element of this invention ((a) supply side, (b) transmission side). It is a schematic diagram (development view of the separation membrane unit) which shows an example of how to use SL type of the separation membrane element of this invention ((a) supply side, (b) transmission side). It is a schematic diagram (partial cross-sectional development view of the separation membrane unit) which shows an example of the depression of the membrane surface.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings, but the present invention is not limited thereto. Further, in the present specification, FIG. 1 is used to explain the schematic configuration of the separation membrane element of the present invention, but the separation membrane element shown in FIG. 1 includes the supply fluid and the permeation fluid of each separation membrane unit in the present invention. The flow paths of the above are not reflected, and they will be described in detail with reference to FIGS. 2-12.

As shown in FIGS. 1 and 2, the separation membrane element of the present invention includes a perforated central tube 2, a plurality of separation membranes 4 having a supply-side surface 10 and a transmission-side surface 11, and a supply-side flow path. It is necessary to provide the material 3 and the permeation side flow path material 5. Further, the plurality of separation membranes 4 included in the separation membrane element 1A of the present invention are arranged and overlapped so that the surfaces 10 on the supply side and the surfaces 11 on the transmission side face each other, and an example is shown in FIG. As shown in the above, it is wound in its longitudinal direction. In the present invention, for convenience of explanation, a separation membrane unit in which the supply side flow path material 3 or the transmission side flow path material 5 is sandwiched between a plurality of separation membranes 4 is referred to as a separation membrane unit.

(1) Separation Membrane As the separation membrane 4 included in the separation membrane element 1A of the present invention, a membrane having separation performance according to the method of use, 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 base material 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 base material. 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 provided with the separation functional layer is referred to as the transmission side surface 11.

The separation function layer may be a layer having both a separation function and a support function, or may have only a separation function. The "separation function layer" means a layer having at least a separation function.

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

On the other hand, as the separation functional layer, a crosslinked polymer layer is preferable from the viewpoint that the pore size can be easily controlled and the durability is excellent. Among them, a polyamide separation functional layer obtained by polycondensing a polyfunctional amine and a polyfunctional acid halide, an organic-inorganic hybrid functional layer, and the like are preferable from the viewpoint of excellent separation performance of the separation component in the feed fluid 101. These separation functional layers can be formed by polycondensing the monomers 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, a polyfunctional amine solution is applied onto the porous support layer, excess polyfunctional amine solution is removed with an air knife or the like, and then an organic solvent solution containing a polyfunctional acid halide is applied. Condensation occurs to form a polyamide separation functional layer.

The material used for the porous support layer and its shape are not particularly limited, but may be, for example, those formed on a substrate by a porous resin. Examples of the porous support layer include layers of polysulfone, cellulose acetate, polyvinyl chloride, epoxy resin or a mixture thereof, or laminated layers thereof, which are chemically, mechanically and thermally. A layer containing polysulfone, which has high stability and whose pore size can be easily controlled, is preferable.

For the porous support layer containing polysulfone, for example, an N, N-dimethylformamide solution of polysulfone is cast on a substrate (for example, a densely woven polyester non-woven fabric) to a certain thickness, and the solution is poured into water. It can be formed by wet coagulation.

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

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 non-woven fabric or a short fiber non-woven fabric.

In order to form the separation membrane element of the present invention, the separation membrane 4 is formed in a rectangular shape. Then, as shown in FIG. 1, the separation membrane 4 having such a shape is wound around the perforated central canal 2. 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 length in the longitudinal direction of the perforated central tube 2). The larger the value of L / W, which is the ratio of (length), the higher the flow velocity when the supply fluid 101 passes through the separation membrane 4, which is preferable from the viewpoint of suppressing concentration polarization. Specifically, the L / W value is preferably 2.5 or more. The length L is preferably 750 mm or more.

(2) Supply-side flow path material The supply-side flow path material 3 included in the separation membrane element 1A of the present invention is arranged so as to be sandwiched between the supply-side surfaces 10 of the separation membrane 4 and is supplied to the separation membrane 4. A flow path for supplying the fluid (that is, a flow path on the supply side) is formed. The supply-side flow path material 3 is preferably shaped so as to disturb the flow of the supply fluid 101 in order to suppress the concentration polarization of the supply fluid 101.

The supply-side flow path material 3 may be a film or a net, or a member having a continuous shape such that a convex object is provided on a sheet having voids, or the separation film 4 may be used. It may have a discontinuous shape showing a projected area ratio greater than 0 and less than 1. Further, the supply-side flow path material 3 may be separable from the separation membrane 4 or may be adhered to the separation membrane 4.

The material of the flow path material 3 on the supply side is not particularly limited, and may be the same material as the separation membrane 4 or a different material.

Regarding 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 amount of fluid passing through is larger than that of the permeation side flow path. Therefore, the projected area ratio of the supply-side flow path material 3 to the separation membrane 4 is preferably 0.03 to 0.80, more preferably 0.05 to 0.50, and 0.08 to 0. It is more preferably .35.

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

If the thickness of the supply-side flow path material 3 is excessively large, the effective membrane area per separation membrane element 1A becomes small. On the other hand, if the thickness of the supply-side flow path material 3 is excessively small, the pressure loss of the supply-side flow path becomes large, and the separation performance and the permeation performance deteriorate. Therefore, the thickness of the supply-side flow path material 3 is preferably 0.08 to 2.0 mm, more preferably 0.20 to 1.00 mm.

The thickness of the flow path material 3 on the supply side can be directly measured by a commercially available thickness measuring device.

(3) Permeation-side flow path material The permeation-side flow path material 5 included in the separation membrane element 1A of the present invention is arranged so as to be sandwiched between the permeation-side surfaces 11 of the separation membrane 4, and permeates the separation membrane 4. A flow path (that is, a flow path on the permeation side) that guides the flowing fluid to the end face of the outlet on the permeation side is formed.

The permeation side flow path material 5 reduces the flow resistance of the permeation side flow path, suppresses the separation membrane 4 from falling into the permeation fluid flow path even under pressure filtration, and stably forms the flow path. The cross-sectional area ratio is preferably 0.3 to 0.75, and more preferably 0.4 to 0.6. The permeation side flow path material 5 includes, for example, a conventional tricot, a weft knitted fabric having a reduced amount of fibers, a sheet in which protrusions are arranged on a porous sheet such as a non-woven fabric, or unevenness in which a film or a non-woven fabric is unevenly processed. A processed sheet can be mentioned.

Here, the cross-sectional area ratio of the permeation side flow path material will be described. When the permeation side flow path material is loaded into the separation membrane element, it is cut so as to pass through the convex portion of the permeation side flow path material along the longitudinal direction of the water collecting pipe, and the convex portion adjacent to the center of the convex portion is cut in its cross section. The ratio of the product of the distance (also called pitch) to the center of the permeation side and the height of the permeation side flow path material to the cross-sectional area of the permeation side flow path material occupied between the center of the convex portion and the center of the adjacent convex portion. Is the cross-sectional area ratio. As a specific measurement method, it is possible to cut the transmission side flow path material as described above and calculate using a microscope image analysis device.

By arranging the permeation side flow path material 5 having a specific cross-sectional area ratio as described above in the separation membrane element 1A of the present invention, the flow resistance of the permeation side flow path can be further reduced. Along with this, when the separation membrane element containing the flow path material having a large flow resistance is operated at the same recovery rate, the flow velocity of the supply fluid 101 is increased and the concentration polarization can be reduced, and the concentration polarization is particularly high under high recovery rate operation. It is possible to further suppress the increase in the amount of water and the generation of scale.

If the thickness of the permeation side flow path material 5 is excessively large, the effective membrane area per separation membrane element 1A becomes small. On the other hand, if the thickness of the permeation side flow path material 5 is excessively small, the pressure loss of the permeation side flow path becomes large. Therefore, the thickness of the permeation side flow path material 5 is preferably 0.05 to 0.50 mm, more preferably 0.10 to 0.40 mm.

The thickness of the permeation side flow path material 5 can be directly measured by a commercially available thickness measuring device.

Since the material of the permeation side flow path material 5 can be easily wound in a spiral shape, its compressive elastic modulus is preferably 0.1 to 5.0 GPa. Examples of the material having a compressive elastic modulus of 0.1 to 5.0 GPa include polyester, polyethylene and polypropylene.

The compressive elastic modulus of the permeation side flow path material 5 can be measured by performing a compression test using a precision universal testing machine and creating a stress-strain diagram.

(4) Separation membrane element <Overview of separation membrane element>
The separation membrane element of the present invention is a spiral type separation membrane element having a long supply-side flow path. In such a separation membrane element, the supply-side surfaces 10 of the separation membrane 4 are expanded into the separation membrane unit of FIG. As illustrated in the figure, the end surface A and the opposite end surface B in the longitudinal direction of the perforated central tube 2, the outer peripheral end portion X and the inner peripheral end portion Y in the direction perpendicular to the longitudinal direction of the perforated central tube 2 Of these, the end face A is continuously closed by 60 to 95% from the outer peripheral end, and the end face B is continuously closed by 75 to 100% from the inner peripheral end. Part Y is closed. That is, the surfaces 10 on the supply side of the separation membrane 4 are open in the vicinity of the inner peripheral end portion in the end surface A, and are open in the vicinity of the outer peripheral end portion and / or the outer peripheral end portion X in the end surface B. On the other hand, it is necessary that only the inner peripheral end portion Y is open between the surfaces 11 on the transmission side of the separation membrane 4, and the other outer peripheral end portions X and the end surfaces A and B are closed. By adhering the plurality of stacked separation membranes in this way, the flow of the supply fluid 101 can be set in the winding direction. Therefore, particularly in the separation membrane element 1A in which the ratio L / W of the separation membrane 4 to the length L in the winding direction and the length W in the longitudinal direction of the effective central canal 2 is 2.5 or more. The flow velocity of the supply fluid 101 can be increased with respect to the conventional separation membrane element 1 in which the supply fluid 101 flows in parallel with the perforated central tube 2, and the element can be made more resistant to fouling and scaling. .. Further, it is preferable that the inner peripheral end portions Y between the permeation side surfaces 11 of the separation membrane 4 are opened by 90% or more from the viewpoint of reducing pressure loss.

5 and 6 are schematic views 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 further wound on the outer peripheral surface of the laminated and wound separation membrane unit. .. Examples of the porous member 20 include a net, a pore film, and the like.

In the embodiment shown in FIGS. 5 and 6, a brine seal is provided in the gap between the separation membrane element 1A and the vessel 23 so that the supply fluid 101, the permeation fluid 102, and the concentrated fluid 103 are not mixed in the vessel 23. 22 is arranged.

<Inverted L-shaped separation membrane element>
The separation membrane element 1A of the present invention includes a plurality of types of separation membrane elements classified in terms of the flow direction of the supply fluid. One of them is an inverted L-shaped separation membrane element. In one aspect of the adhesion portion of the separation membrane in the inverted L-shaped separation membrane element and its usage, as shown in FIG. 7 (expanded view of the separation membrane unit), the end faces A of the supply-side surfaces 10 of the separation membrane 4 are connected to each other. The supply fluid 101 is supplied from the opening of the above, and the concentrated fluid 103 is discharged from the opening of the outer peripheral end portion X between the supply-side surfaces 10 of the separation membrane 4. The separation membrane element 1A to which such a usage method is applied is referred to as an inverted L-type separation membrane element here.

In the inverted L-shaped separation membrane element, for example, the end face A and the outer peripheral end portion X are opened by 5% or more between the supply-side surfaces 10 of the separation membrane 4, and the end face B and the inner peripheral end portion Y are opened. However, it is preferable that all of them are closed. Further, it is necessary that the surfaces 11 on the transmission side of the separation membrane 4 are opened only at the inner peripheral end portion Y, and the outer peripheral end portions X and the end surfaces A and B are all closed. That is, in the inverted L-shaped separation membrane element, the end faces B between the supply-side faces 10 of the separation membrane 4 are completely closed. On the other hand, the end faces A of the supply-side surfaces 10 of the separation membrane 4 are open in the vicinity of the inner peripheral end portion from the viewpoint of homogenizing the flow of the supply fluid 101 in the supply-side flow path. It is more preferable that the opening is ~ 40%. The portion (opening) opened in the end surface A is not limited to one place, and may be divided into a plurality of parts. The outer peripheral end X between the supply-side surfaces 10 of the separation membrane may have a small aperture ratio in order to increase the flow velocity in the vicinity of the outlet of the concentrated fluid 103. The opening at the outer peripheral end X is not limited to one place, and may be divided into a plurality of places. In the present invention, the aperture ratio is the ratio of the length of the opening to the total length of the separation membrane 4 at the side of the separation membrane provided with the opening. 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 opening is divided into a plurality of, the opening on the innermost peripheral side. The length is from the inner peripheral end to the outer peripheral end of the opening on the outermost peripheral side.

<L-type separation membrane element>
The separation membrane element 1A of the present invention also includes an L-type separation membrane element. In one aspect of the bonding portion of the separation membrane in the L-shaped separation membrane element and its usage, as shown in FIG. 8 (expanded view of the separation membrane unit), the outer peripheral end portions of the supply-side surfaces 10 of the separation membrane 4 are connected to each other. The supply fluid 101 is supplied from the opening of X, and the concentrated fluid 103 is discharged from the opening of the end faces A between the supply-side surfaces 10 of the separation membrane 4. The separation membrane element 1A to which such a usage method is applied is referred to as an L-type separation membrane element here.

In the L-shaped separation membrane element, for example, the end face A and the outer peripheral end portion X are opened by 5% or more between the supply-side surfaces 10 of the separation membrane 4, and the end face B and the inner peripheral end portion Y are open. However, it is preferable that all of them are closed. Further, it is necessary that the surfaces 11 on the transmission side of the separation membrane 4 are opened only at the inner peripheral end portion Y, and the outer peripheral end portions X and the end surfaces A and B are all closed. That is, in the L-shaped separation membrane element, the end faces B between the supply-side faces 10 of the separation membrane 4 are completely closed. The L-type separation membrane element has the same bonding method as the inverted L-type separation membrane element, but the concentrated fluid 103 is discharged from the end faces A of the supply-side surfaces 10 of the separation membrane 4, so that the above It is preferable that the aperture ratio in the vicinity of the inner peripheral end portion Y of the end surface A is smaller than that in the case of the inverted L-shaped separation membrane element. Similarly, since the outer peripheral end portions X between the supply-side surfaces 10 of the separation membrane 4 supply the supply fluid 101, the aperture ratio of the outer peripheral end portions X is preferably 90% or more. The openings in the end face A and the outer peripheral end X are not limited to one place, and may be divided into a plurality of places. 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.

<Inverted S-type separation 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 adhesion portion of the separation membrane in the inverted S-type separation membrane element and its usage, as shown in FIG. 9 (expanded view of the separation membrane unit), the end faces A of the supply-side surfaces 10 of the separation membrane 4 are connected to each other. The supply fluid 101 is supplied from the opening near the inner circumference of the above, and the concentrated fluid 103 is discharged from the opening near the outer periphery of the end faces B between the supply-side surfaces 10 of the separation membrane 4. The separation membrane element 1A to which such a usage method is applied is referred to as an inverted S-type separation membrane element here.

In the inverted S-type separation membrane element, the outer peripheral end portions X between the supply-side surfaces 10 of the separation membrane 4 are completely closed. The end surface A to which the supply fluid 101 between the supply side surfaces 10 of the separation membrane 4 is supplied is located near the inner peripheral end portion Y from the viewpoint of homogenizing the flow of the supply fluid 101 in the supply side flow path. It is open, more preferably 5-40% open. The portion (opening) opened in the end surface A is not limited to one place, and may be divided into a plurality of parts. The end surface B from which the concentrated fluid 103 between the supply side surfaces 10 of the separation membrane 4 is discharged has an opening in the vicinity of the outer peripheral end portion X from the viewpoint of homogenizing the flow of the supply fluid 101 in the supply side flow path. In order to increase the flow velocity in the vicinity of the outlet of the concentrated fluid 103, the aperture ratio may be smaller than that of the end face on the supply side. The opening in the end face B is not limited to one place, and may be divided into a plurality of openings. 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 opening is divided into a plurality of parts on each end face. Is the length from the inner peripheral end of the opening on the innermost peripheral side to the outer peripheral end of the opening on the outermost peripheral side in each end face.

<S-type separation membrane element>
The separation membrane element 1A of the present invention also includes an S-type separation membrane element. In one aspect of the adhesion portion of the separation membrane in the S-type separation membrane element and its usage, as shown in FIG. 10 (expanded view of the separation membrane unit), the end faces B of the supply-side surfaces 10 of the separation membrane 4 are connected to each other. The supply fluid 101 is supplied from the opening near the outer periphery, and the concentrated fluid 103 is discharged from the opening near the inner circumference of the end faces A between the supply-side surfaces 10 of the separation membrane 4. The separation membrane element 1A to which such a usage method is applied is referred to as an S-type separation membrane element here.

In the S-type separation membrane element, the outer peripheral end portions X between the supply-side surfaces 10 of the separation membrane 4 are completely closed. The S-type separation membrane element has the same bonding method as the inverted S-type separation membrane element, but the concentrated fluid 103 is provided from the opening near the inner peripheral end portion Y of the end faces A of the supply-side surfaces 10 of the separation membrane 4. It is preferable that the aperture ratio in the vicinity of the inner peripheral end portion of the end surface A is smaller than that in the case of the inverted S-type separation membrane element. Similarly, the opening in the vicinity of the outer peripheral end portion X of the end faces B between the supply-side surfaces 10 of the separation membrane 4 supplies the supply fluid 101, and therefore is preferably larger than the opening in the vicinity of the inner peripheral end portion Y. .. The openings in the end faces A and B are not limited to one place, and may be divided into a plurality of openings. 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. 10, and when the opening is divided into a plurality of parts on each end face. Is the length from the inner peripheral end of the opening on the innermost peripheral side to the outer peripheral end of the opening on the outermost peripheral side in each end face.

<Reverse SL type separation membrane 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 portion of the separation membrane in the inverted SL type separation membrane element and its usage, as shown in FIG. 11 (expanded view of the separation membrane unit), the end faces B of the supply-side surfaces 10 of the separation membrane 4 are connected to each other. The outer peripheral end portion X between the outer peripheral portions of the separation membrane 4 and the supply side surfaces 10 of the separation membrane 4 is open, and the inner peripheral periphery of the end surface A between the supply side surfaces 10 of the separation membrane 4 is open. In this separation membrane element 1A, a method of supplying the supply fluid 101 from the opening of the end surface A near the inner peripheral end portion Y is referred to as an inverted SL type element. This separation membrane element has a form such that a combination of an inverted S type and an inverted L type, that is, a combination of the above-mentioned inverted S type separation membrane element and the inverted L type separation membrane element. There is. The opening position of the outer peripheral end portion X is not limited. 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.

<SL type separation membrane element>
The separation membrane element 1A of the present invention also includes an SL type separation membrane element. In one aspect of the adhesion portion of the separation membrane in the SL type separation membrane element and its usage, as shown in FIG. 12 (expanded view of the separation membrane unit), the end faces B of the supply-side surfaces 10 of the separation membrane 4 are connected to each other. The outer peripheral end portions X near the outer periphery and between the supply-side surfaces 10 of the separation membrane 4 are open, and the inner peripheral periphery of the end faces A between the supply-side surfaces 10 of the separation membrane 4 are open. In the separation membrane element 1A, a method of supplying the supply fluid 101 from the openings of the outer peripheral end portion X and the end surface B is referred to as an SL type element. This separation membrane element is a separation membrane element such as a combination of S-type and L-type, that is, a form in which the above-mentioned S-type separation membrane element and L-type separation membrane element are added together. The opening position of the outer peripheral end portion X is not limited. 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.

<How to close the separation membrane / Closing location>
In manufacturing the above-mentioned various separation membrane elements, the method of closing the end faces A and the end faces B in the longitudinal direction of the perforated central canal 2 between the supply-side surfaces 10 of the separation membrane 4 is performed before winding. There is a way to do it after the siege. Examples of the method performed before winding include adhesion with an adhesive, adhesion with a hot melt resin, and adhesion with an adhesive tape. If it is performed after winding, a method of applying an adhesive from the outside and adhering the adhesive can be mentioned.

Further, as shown in FIG. 1, an end plate 21 may be attached to the end face A and the end face B in the longitudinal direction of the perforated central tube 2 in order to prevent telescoping of the wound body. Since the fluid flows in and out of the end plate 21 mounted on the end face A, it is necessary that a hole exists in the end plate 21. The end plate 21 mounted on the end face B has a hole when the fluid enters and exits from the end face B, and may or may not have a hole when the fluid does not enter and exit from the end face B. Examples of the material of the end plate 21 include ABS, polyvinyl chloride, polyethylene or polypropylene.

As a method of closing the inner peripheral end portion Y or the outer peripheral end portion X between the supply-side surfaces 10 of the separation membrane 4, for example, adhesion with an adhesive, adhesion with a hot melt resin, adhesion with an adhesive tape, separation film 4 Folding, etc.

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

The supply-side closing member 6 and the transmission-side closing member 7 for closing the supply-side surfaces 10 and the transmission-side surfaces 11 are urethane-based adhesives in consideration of adhesive strength, hardness at the time of curing, handling property, and the like. It is desirable to use an agent or an epoxy adhesive. The viscosity of the adhesive before curing is preferably 4 to 15 Pa · s from the viewpoint of facilitating its handling and suppressing the generation of wrinkles when winding the separation membrane 4. It is more preferably ~ 12 Pa · s.

As described above, the perforated central tube 2, the separation membrane 4, the supply side flow path material 3 and the transmission side flow path material 5 are arranged, and the end portions X and Y and the end faces A and B are closed or opened to supply the fluid. Since the flow of the fluid 101 can be directed along the longitudinal direction of the separation membrane 4, the supply fluid 101 can be a spiral type separation membrane element having a high flow velocity. However, if the supply fluid 101 is simply made into a spiral type separation membrane element having a high flow velocity by the above method, the pressure loss of the supply fluid 101 becomes larger than that of the normal separation membrane element 1, and the winding body is deformed. There is a problem that telescoping is likely to occur, which causes a short path of the supply fluid 101 and the separation performance is not sufficiently exhibited. In addition, when a high pressure is applied to the flow path on the supply side, the membrane surface is pushed toward the permeation side, causing the membrane surface to drop to the permeation side and the member that closes the end to be deformed. There is also a problem that the functional layer of the surface is damaged and the separation performance is significantly deteriorated.

On the other hand, in the present invention, the sectional views of the separation membrane unit of FIGS. 3 and 4 (however, both views show the end portion on the end face B side) and the development of the separation membrane unit of FIGS. 7 to 12. As illustrated in the figure, the separation membrane element 1A sets the lengths of the openings of the end faces A and the end faces B of the supply-side surfaces 10 of the separation membrane 4 to OL (A) and OL (B), respectively. The distance from the end face A and the end face B of the inner end of the perforated center tube 2 in the longitudinal direction of the permeation side closing member 7 for closing the end faces A and the end faces B of the permeation side faces 11 of 4. Let p (A) and p (B), respectively, and the inside of the supply-side closing member 6 for closing the end faces A and the end faces B of the supply-side faces 10 of the separation membrane 4 in the longitudinal direction of the perforated central tube 2. The distances from the end face A and the end face B of each of the ends are q (A) and q (B), respectively, and the supply side closure for closing the end faces A and the end faces B of the supply side faces 10 of the separation membrane 4 are closed. Assuming that the widths of the perforated central tube 2 in the longitudinal direction of the portion of the member 6 in contact with the separation membrane 4 are r (A) and r (B), respectively, p (A) ≧ q (A) and p ( B) ≧ q (B), and at least one of the following requirements (i) and (ii) shall be satisfied.
(I) In the supply-side closing member 6 for closing the end faces B between the supply-side surfaces 10 of the separation membrane 4, the length is at least OL (A) or longer from the inner peripheral side end to the outer peripheral side. The r (B) of the portion is continuously present by 3 mm or more.
(Ii) In the supply-side closing member 6 for closing the end faces A of the supply-side surfaces 10 of the separation membrane 4, the length is at least OL (B) or longer from the outer peripheral end to the inner peripheral side. The portion r (A) 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 with the separation membrane unit unfolded, respectively. Further, the inner circumference and the outer circumference refer to the portion closest to the perforated central canal 2 in the expanded state of the separation membrane unit as the inner circumference, and the portion farthest from the perforated central canal 2 as the outer circumference.

In the present invention, by setting p (A) ≧ q (A) and p (B) ≧ q (B) in the entire area of the separation membrane 4, the separation membrane 4 is supplied to the effective membrane portion of the surface 10 on the supply side. Since the side closing member 6 does not come into contact with the film surface, damage to the film surface can be prevented.

Then, for example, as shown in FIGS. 7, 9 and 11, when the supply fluid is allowed to flow in through the opening of the length OL (A) provided at the inner peripheral end of the end surface A, the end surface B on the opposite side of the opening is used. The supply-side closing member 6 on the inner peripheral side of the above supports the load due to the flow resistance. Further, as shown in FIGS. 10 and 12, for example, when the supply fluid is allowed to flow in through the opening of the length OL (B) provided in the end surface B, the supply side closing member of the end surface A on the opposite side of the opening. 6 will support the load due to the flow resistance. Further, for example, as shown in FIG. 8, when the supply fluid is allowed to flow in from the opening provided in the outer peripheral end portion X, the load is supported by the flow resistance by the supply side closing member 6 on both the end face A and the end face B. However, the portion of the supply-side closing member 6 on the opposite side (that is, the end surface B) of the end surface A where the opening exists is the weakest. If the adhesion of the supply-side closing member 6 is weak, the separation membrane element will be deformed from that portion. However, in the present invention, by satisfying at least one of the above (i) and (ii), the closure between the supply-side surfaces of the separation membrane can be further strengthened, and the separation membrane element 1A has a large flow resistance. It is possible to prevent the winding body from being deformed even when it is applied.

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 inverted S-type, S-type, inverted SL-type, and SL-type separation membrane elements, it is necessary to strengthen the end face on the side opposite to the end face on the side where the fluid whose supply fluid 101 has a higher pressure is supplied. .. That is, it is necessary to satisfy at least the above (i) for the inverted S type and the inverted SL type, and at least the above (ii) for the S type and the SL type.

Here, when an adhesive is applied from the outside to the end faces A and B of the supply-side surfaces of the separation membrane after winding, r (A) is satisfied in order to satisfy the above (i) and (ii). ) And r (B) to be 3 mm or more, it is preferable to apply pressure from the outside to push the adhesive, or to suck the adhesive from the opposite end face.

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

Regarding the ratio of p (B) and q (B), q (B) / p (B) ≧ 0.5 because the supply side flow path other than the effective membrane area is narrowed and the supply fluid 101 flows at a higher flow rate. Is preferable. For the same reason, the ratio of p (A) to q (A) is preferably q (A) / p (A) ≧ 0.5. q / p is an average value measured at intervals of 20 mm in the element.

Further, when the coefficient of variation of r (A) or r (B), which is 3 mm or more, is 0.00 or more and 0.20 or less, the load applied due to the pressure loss can be supported more uniformly, and r (A). Alternatively, even in a situation where r (B) is close to 3 mm, deformation of the separation membrane 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 in the winding direction and dividing the standard deviation by the average value.

<Water treatment equipment>
The separation membrane element 1A of the present invention can be applied to a water treatment device such as an RO water purifier. In the case of the inverted L-type, inverted S-type, and inverted SL-type separation membrane elements exemplified in FIGS. The fluid 101 is supplied and connected to the water treatment device so as to discharge the concentrated fluid from the openings of the end faces B, the outer peripheral end portions X, or both of the supply-side surfaces 10 of the separation membrane 4. Therefore, the supply fluid supply unit is connected so as to communicate with the inner peripheral side opening (the inner peripheral side opening of the end surface A) between the supply side surfaces 10 of the separation membrane 4, and the supply side of the separation membrane 4 is connected. The concentrated fluid discharge portion is connected so as to communicate with the opening on the outer peripheral side of the surfaces 10 (the opening of the end surface B, the outer peripheral end X, or both of them).

On the other hand, in the case of L-type, S-type, and SL-type separation membrane elements, the supply fluid 101 is supplied from the openings of the end faces B, the outer peripheral end portions X, or both of the supply-side surfaces 10 of the separation membrane 4. It is connected to the water treatment device so as to discharge the concentrated fluid 103 from the opening on the inner peripheral side of the end surface A between the supply side surfaces 10 of the separation membrane 4. Therefore, the supply fluid supply section is connected so as to communicate with the opening on the outer peripheral side of the supply-side surfaces 10 of the separation membrane 4 (the opening of the end surface B, the outer peripheral end portion X, or both of them), and the separation membrane 4 is connected. The concentrated fluid discharge portion is connected so as to communicate with the opening on the inner peripheral side of the supply-side surfaces 10 (the opening on the inner peripheral side of the end surface A).

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

(P (A), p (B), q (A), q (B), r (A), r (B))
The measurement of p (A), p (B), q (A), q (B), r (A), r (B) is a state in which the separation membrane element is unwound and the separation membrane element is unfolded. Do it at. Measure with a caliper at intervals of 20 mm toward the winding direction, and calculate the average value. When deploying the separation membrane element, the separation membrane unit is stretched while peeling off the adhesive adhering the surfaces on the supply side of the separation membrane.

(OL (A), OL (B))
The OL (A) and OL (B) are measured using a caliper with the separation membrane element unwound and the separation membrane element unfolded.

(Initial water production volume and rate of decrease in water production volume)
Tap water was used as the supply fluid. The concentrated water valve was opened at an operating pressure of 0.2 MPa, and a flushing operation was performed for 30 minutes. Then, 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 water production amount (L / min) was measured. Then, the amount of water produced after 100 hours of operation was measured in the same manner, and the rate of decrease in water production was calculated from the following formula.

Water production reduction rate (%) = 100 × (1- (water production after 100 hours operation) / (initial water production))
(Recovery rate)
In the measurement of the initial water production amount, the ratio of the supplied water amount supplied per minute to the permeated water amount was taken as the recovery rate.

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

TDS removal rate (%) = 100 × {1- (TDS concentration in permeated water / TDS concentration in feed water)}
(Example 1)
A 15.2 mass% N-dimethylformamide solution of polysulfone on a non-woven fabric made of polyethylene terephthalate fiber (thread diameter: 1 decitex, thickness: about 0.09 mm, density: 0.80 g / cm ^{3) at room temperature (180 μm thickness).} Cast at 25 ° C.), immediately immersed in pure water, left for 5 minutes, and immersed in warm water at 80 ° C. for 1 minute to form a porous support layer (thickness: 0. 13 mm) was produced.

The porous support layer was immersed in a 3.8 mass% aqueous solution of m-phenylenediamine for 2 minutes, then slowly pulled up in the vertical direction, and nitrogen was blown from an air nozzle to remove excess aqueous solution from the surface of the porous support layer. After that, a 0.175 mass% n-decane solution of trimesic acid chloride was applied so that the surface was completely wet, allowed to stand for 1 minute, and held vertically for another 1 minute to drain. Then, it was washed with hot water of 90 degreeC for 2 minutes, and the separation membrane was obtained.

When the separation membrane thus obtained is folded so that the crease becomes the inner peripheral end portion Y and the supply side is inward, the length L of the separation membrane in the separation membrane unit in the winding direction is 1200 mm. A plurality of sheets were cut so that the length W of the effective central tube 2 in the longitudinal direction was 250 mm. Then, on the cut separation membrane, a net (thickness: 0.5 mm, pitch: 3 mm × 3 mm) is used as a flow path material on the supply side so that the inclination angle of the net constituent yarn is 45 ° with respect to the winding direction. Placed in.

As shown in FIG. 7, the surfaces on the supply side of the separation membrane are continuously urethane 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 opens by 20%. A system adhesive was applied. The end face B was continuously coated with a urethane adhesive so as to be completely closed. Then, the separation membrane was folded with the supply side side inside so that the inner peripheral end portion Y became a crease. Urethane-based adhesives were continuously applied to the permeation-side surfaces of the separation membrane so that the inner peripheral end portions were fully opened and the other end surfaces and the like were completely closed. At this time, the adhesive on the permeation side of the end face A and the end face B was applied to the inside of the supply side so that p (A)> q (A) and p (B)> q (B).

The permeation side flow path material was prepared as follows using an applicator loaded with a comb-shaped shim having a slit width of 0.5 mm and a pitch of 0.9 mm. That is, while adjusting the temperature of the backup roll to 20 ° C., when it is used as a separation membrane element, it is linear from the inner end to the outer end in the winding direction so as to be perpendicular to the longitudinal direction of the perforated central tube. High crystalline PP (MFR 1000g / 10 minutes, melting point 161 ° C) 60% by mass and low crystalline α-olefin polymer (manufactured by Idemitsu Kosan Co., Ltd .; low stereoregular polypropylene "L-MODU / S400" (trade name)) A composition pellet composed of 40% by mass was prepared by applying it on a polypropylene at a resin temperature of 205 ° C. and a traveling speed of 10 m / min. The non-woven fabric had a thickness of 0.07 mm, a basis weight of 35 g / m ² , and an embossed pattern (circular φ1 mm, grid pattern with a pitch of 5 mm).

The prepared permeation-side flow path material is cut and placed on the permeation-side surface of the separation membrane sandwiching the supply flow path material, and these are placed in a perforated center tube (acrylonitrile-butadiene-styrene) made of ABS (acrylonitrile-butadiene-styrene). Width: 300 mm, diameter: 18 mm, number of holes 10 x linear 1 row) was spirally surrounded. A film having holes was wrapped around the outer peripheral surface of the spiral separation membrane element. In this film, four holes having a width (major axis) of 40 mm and a height (minor axis) of 10 mm are formed in the central portion of the film at a width of 200 mm 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 cutting the edges at both ends of the separation membrane element coated with the film, a brine seal for separating the feed fluid and the concentrated fluid was attached to the outer peripheral surface to prepare the separation membrane element.

The average value of the adhesive width of each sealing 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.

Finally, in order to prevent a short path of the fluid, an adhesive was applied to the vicinity of the outer periphery of the end face A and the end face B.

When the separation membrane element was put in a vessel, the usage pattern was inverted L-shaped, and each performance was evaluated with a recovery rate of 90%, the results are shown in Table 1.

(Examples 2 to 5)
The application position and the application amount of the adhesive for adhering the end face A and the end face B are changed, and p (A), q (A), p (B), q (B), r (A), r ( Separation membranes and separation membrane elements were prepared in the same manner as in Example 1 except that B) was as shown in Table 1.

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

(Examples 6 to 10)
The application position and the application amount of the adhesive for adhering the end face A and the end face B are changed, and p (A), q (A), p (B), q (B), r (A), r ( Separation membranes and separation membrane elements were prepared in the same manner as in Example 1 except that B) was as shown in Table 2.

Table 2 shows the results when 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 usage pattern was L-shaped.

(Example 11)
Each member was prepared in the same manner as in Example 1, and the separation membrane element was wound in the same manner as in Example 1 except that the adhesive was not applied to the supply-side surface of the separation membrane before winding. bottom. Adhesive is applied from the outside to the end face B side of the wound element in the longitudinal direction, and the adhesive is sucked from the end face A side with a vacuum pump to the depth of the supply side flow path (in the longitudinal direction of the perforated central tube). Infiltrated. An adhesive was applied to the end face A side of the surface on the supply side of the separation membrane so that the aperture ratio on the raw water side was 20% (without suction) to prepare a separation membrane element.

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

(Example 12)
Separation membranes and separation membrane elements were prepared in the same manner as in Example 11.

Table 3 shows the results when 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 usage pattern was L-shaped.

(Example 13)
The separation membrane and the separation membrane element were produced in the same manner as in Example 1 except that the number of pairs of separation membranes and members to be wound was three and the winding circumference was 3 inches.

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

(Examples 14 to 16)
Separation membranes and separation membrane elements were produced in the same manner as in Example 1 except that the aperture ratios of the openings of the end face A were as shown in Table 3.

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

(Example 17)
The separation membrane was cut in the same manner as in Example 1 except that the membrane and the flow path material were cut so that L and W were as shown in Table 4, and the number of pairs of membranes and the flow path material to be wound was two. And the separation membrane element was made.

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

(Example 18)
Regarding the surface on the supply side of the separation membrane, the opening width in the vicinity of the outer peripheral portion of the separation membrane element of the end surface B is set to 200 mm, and the outer peripheral end portion is changed to a non-permeable film having no holes. Separation membranes and separation membrane elements were produced in the same manner as in Example 1 except that the opening width of X was set to 0 mm.

Table 4 shows the results when 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 usage pattern was inverted S type.

(Example 19)
With respect to the surface on the supply side of the separation membrane, urethane adhesive was applied so that the opening width in the vicinity of the outer peripheral portion of the separation membrane element of the end surface B was 100 mm, and the outer peripheral end portion X was continuously opened 100 mm from the end surface B side. A separation membrane and a separation membrane element were produced in the same manner as in Example 1 except for the above.

Table 4 shows the results when 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 usage pattern was an inverted SL type.

(Example 20)
Each member was prepared in the same manner as in Example 1, and the separation membrane element was wound in the same manner as in Example 1 except that the adhesive was not applied to the supply-side surface of the separation membrane before winding. bottom. Next, a urethane adhesive is applied from the outside to the inner circumference 20% of the end face B side in the longitudinal direction of the wound element, the outer circumference 80% of the end face B side is masked, and then a vacuum is applied from the end face A side. The adhesive was infiltrated in the longitudinal direction of the perforated central tube by suction with a pump. After that, a urethane adhesive is applied to the portion of the outer circumference 80% on the end face B side (without suction), and further, the opening on the end face A side is continuously 20% from the inside on the end face A side. Adhesive was applied (no suction).

Table 4 shows the results when 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 usage pattern was inverted L-shaped.

(Example 21)
A separation membrane element was produced in the same manner as in Example 18.

Table 5 shows the results when 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 usage pattern was inverted S type.

(Example 22)
Urethane adhesive was applied to the surface on the supply side of the separation membrane so that the opening width in the vicinity of the outer peripheral portion of the separation membrane element of the end surface B was 100 mm, and the outer peripheral end portion X was continuously opened 100 mm from the end surface A side. A separation membrane and a separation membrane element were produced in the same manner as in Example 1 except for the above.

Table 5 shows the results when 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 usage pattern was SL type.

(Comparative Example 1)
Each member was prepared in the same manner as in Example 1, and the separation membrane element was wound in the same manner as in Example 1 except that the adhesive was not applied to the supply-side surface of the separation membrane before winding. bottom. An adhesive was applied from the outside to the end face B side in the longitudinal direction of the wound element. At this time, no work such as suction or pushing was performed. An adhesive was applied to the end face A side in the longitudinal direction so that the aperture ratio on the raw water side was 20% to prepare a separation membrane element.

When the separation membrane element was put in a vessel and each performance was evaluated under the same conditions as in Example 1, the results were shown in Table 6. Since no work such as suction or pushing was performed on the element, it is considered that the separation membrane element was deformed during the flushing operation due to the small r (B) of 1 mm, and a short pass occurred.

(Comparative Example 2)
The application position and the application amount of the adhesive for adhering the end face A and the end face B are changed, and p (A), q (A), p (B), q (B), r (A), r ( Separation membranes and separation membrane elements were prepared in the same manner as in Example 1 except that B) was as shown in Table 6.

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

(Comparative Example 3)
The application position and the application amount of the adhesive for adhering the end face A and the end face B are changed, and p (A), q (A), p (B), q (B), r (A), r ( Separation membranes and separation membrane elements were prepared in the same manner as in Example 1 except that B) was as shown in Table 6.

When the separation membrane element was put in a vessel and each performance was evaluated under the same conditions as in Example 1, the results were shown in Table 6. In the element, q (A) / p (A) is 2, and the supply-side adhesive is applied to the effective film portion, so that it is considered that the film surface is damaged during flushing.

(Comparative Example 4)
The application position and the application amount of the adhesive for adhering the end face A and the end face B are changed, and p (A), q (A), p (B), q (B), r (A), r ( Separation membranes and separation membrane elements were prepared in the same manner as in Example 1 except that B) was as shown in Table 6.

When the separation membrane element was put in a vessel and each performance was evaluated under the same conditions as in Example 1, the results were shown in Table 6. In the element, q (B) / p (B) is 2, and the supply-side adhesive is applied to the effective film portion, so that it is considered that the film surface is damaged during flushing.

(Comparative Example 5)
The application position and the application amount of the adhesive for adhering the end face A and the end face B are changed, and p (A), q (A), p (B), q (B), r (A), r ( Separation membranes and separation membrane elements were prepared in the same manner as in Example 1 except that B) was as shown in Table 6.

When the separation membrane element was put in a vessel and each performance was evaluated under the same conditions as in Example 1, the results were shown in Table 6. In the element, q (A) / p (A) and q (B) / p (B) are 2, and the supply-side adhesive is applied to the effective film portion, so that film surface damage occurs during flushing. It is thought that it was.

(Comparative Example 6)
The application position and the application amount of the adhesive for adhering the end face A and the end face B are changed, and p (A), q (A), p (B), q (B), r (A), r ( Separation membranes and separation membrane elements were prepared in the same manner as in Example 1 except that B) was as shown in Table 7.

Table 7 shows the results when 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 L-shaped. In the element, q (A) / p (A) and q (B) / p (B) are 2, and the supply-side adhesive is applied to the effective film portion, so that film surface damage occurs during flushing. It is thought that it was. It is probable that the separation membrane element was deformed during the flushing operation due to the small r (A) and r (B) on the opposite side of the opening as 2 mm, and a short pass occurred.

(Comparative Example 7)
A liquid-tight film is formed on the outer peripheral surface of the spiral separation membrane element without adhering the surfaces on the supply side of the separation membrane to each other so as to be in a general usage pattern (type I) as shown in FIG. Separation membranes and separation membrane elements were prepared in the same manner as in Example 1 except that they were covered with.

When the separation membrane element was put in a vessel and each performance was evaluated under the same conditions as in Example 1, the results were shown in Table 7. Since the element is a normal type I element and the flow velocity on the supply side is slower than that of the element of the present invention, it is considered that concentration polarization of the film surface occurs, the TDS removal rate decreases, and the amount of water produced decreases due to scale generation. Be done.

1 Separation membrane element (type I)
1A Separation membrane element 2 Perforated central tube 3 Supply side flow material 4 Separation membrane 5 Permeation side flow material 6 Supply side closure member 7 Permeation side closure member 10 Supply side surface of separation membrane 11 Permeation side surface of separation membrane 20 Porous member 21 Perforated end plate 22 Brine seal 23 Vessel 101 Supply fluid 102 Permeation fluid 103 Concentrated fluid A, B End face in the longitudinal direction of the perforated central canal X Outer circumference in the direction perpendicular to the longitudinal direction of the perforated central canal End Y Inner peripheral end in the direction perpendicular to the longitudinal direction of the perforated central canal L Length of the supply-side flow path (length of the separation membrane in the direction perpendicular to the longitudinal direction of the perforated central canal)
W Supply side flow path width (length of separation membrane in the longitudinal direction of the perforated central canal)
Opening lengths of end faces A and end faces B between the supply-side faces of the OL separation membrane

Claims (12)

A perforated central canal, a plurality of separation membranes having a supply-side surface and a permeation-side surface, a supply-side flow path material, and a permeation-side flow path material are provided.
The plurality of separation membranes are arranged and stacked so that the surfaces on the supply side and the surfaces on the transmission side face each other, and the supply side flow path material is between the surfaces on the supply side of the separation membrane. The permeation side flow path material is arranged between the permeation side surfaces of the separation membrane, and the separation membrane, the supply side flow path material, and the permeation side are arranged around the perforated center tube. The flow path material is wound in the longitudinal direction of the separation membrane, and is formed.
The supply-side surfaces of the separation membrane are the end surface A in the longitudinal direction of the perforated central canal and the end surface B on the opposite side thereof, and the outer peripheral end portion X and the inside in the direction perpendicular to the longitudinal direction of the effective central canal. Among the peripheral end portions Y, the end surface A is continuously closed by 60 to 95% from the outer peripheral end, and the end surface B is continuously closed by 75 to 100% from the inner peripheral end. The inner peripheral end portion Y is closed, and only the inner peripheral end portion Y is open between the surfaces on the transmission side of the separation membrane, and the outer peripheral end portion X and the end surfaces A and B are closed. Ori,
The lengths of the openings of the end faces A and the end faces B between the supply-side surfaces of the separation membrane are set to OL (A) and OL (B), respectively.
The distance from the end surface A and the end surface B of the inner end of the member for closing the end surface A and the end surface B between the permeation side surfaces of the separation membrane in the longitudinal direction of the perforated central canal. , P (A) and p (B), respectively.
The distance from the end surface A and the end surface B of the inner end of the member for closing the end surface A and the end surface B between the supply-side surfaces of the separation membrane in the longitudinal direction of the perforated central canal. , Q (A) and q (B), respectively.
The width in the longitudinal direction of the perforated central canal of the portion of the member for closing the end surface A and the end surface B of the supply-side surfaces of the separation membrane in contact with the separation membrane is r ( If A) and r (B),
p (A) ≧ q (A) and p (B) ≧ q (B),
A separation membrane element that meets at least one of the following requirements (i) and (ii).
(I) In the member for closing the end faces B between the supply-side surfaces of the separation membrane, r (a portion having a length of at least OL (A) or more from the inner peripheral end to the outer peripheral side). B) exists continuously for 3 mm or more.
(Ii) In the member for closing the end faces A between the supply-side surfaces of the separation membrane, r (i) of a portion having a length of at least OL (B) or more from the outer peripheral end to the inner peripheral side. A) exists continuously for 3 mm or more. 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 the end faces B are 100% closed and the outer peripheral end portion X is opened by 5% or more between the surfaces on the supply side of the separation membrane. The separation membrane element according to any one of claims 1 to 3, wherein the member for closing the end faces A and the end faces B between the supply-side faces is a urethane-based adhesive or an epoxy-based adhesive. The separation membrane has a L / W of 2.5 or more, which is the ratio of the length L in the longitudinal direction of the separation membrane to the length W in the direction perpendicular to the longitudinal direction of the separation membrane. The separation membrane element according to any one of 1 to 4. The separation membrane element according to any one of claims 1 to 5, wherein q (B) / p (B) ≥ 0.5 with respect to p (B) and q (B). The separation membrane element according to any one of claims 1 to 6, wherein q (A) / p (A) ≥ 0.5 with respect to p (A) and q (A). The supply fluid is supplied from the opening on the inner peripheral side between the supply-side surfaces of the separation membrane, and the supply fluid is supplied.
The method for using the separation membrane element according to any one of claims 1 to 7, wherein the concentrated fluid is discharged from the opening on the outer peripheral side between the supply-side surfaces of the separation membrane. The supply fluid is supplied from the openings on the outer peripheral sides of the supply-side surfaces of the separation membrane.
The method for using the separation membrane element according to any one of claims 1 to 7, wherein the concentrated fluid is discharged from the opening on the inner peripheral side between the supply-side surfaces of the separation membrane. The separation membrane element according to any one of claims 1 to 7, and the separation membrane element.
A supply fluid supply unit that is connected so as to communicate with an opening on the inner peripheral side of the supply side surfaces of the separation membrane and supplies the supply fluid.
A water treatment apparatus having a concentrated fluid discharging portion connected so as to communicate with an opening on the outer peripheral side between the supply-side surfaces of the separation membrane and discharging the concentrated fluid. The separation membrane element according to any one of claims 1 to 7, and the separation membrane element.
A supply fluid supply unit that is connected so as to communicate with an opening on the outer peripheral side of the supply side surfaces of the separation membrane and supplies the supply fluid.
A water treatment device having a concentrated fluid discharge unit that is connected so as to communicate with an opening on the inner peripheral side of the supply-side surfaces of the separation membrane and discharges the concentrated fluid. A perforated central canal, a plurality of separation membranes having a supply-side surface and a permeation-side surface, a supply-side flow path material, and a permeation-side flow path material are provided.
The plurality of separation membranes are arranged and stacked so that the surfaces on the supply side and the surfaces on the transmission side face each other, and are wound in the longitudinal direction thereof.
The supply-side flow path material is arranged between the supply-side surfaces of the separation membrane.
The permeation-side flow path material is arranged between the permeation-side surfaces of the separation membrane.
The surfaces on the supply side of the separation membrane are the end surface A in the longitudinal direction of the perforated central canal, the end surface A in the end surface B, and the outer peripheral end portion X in the direction perpendicular to the longitudinal direction of the effective central canal. And the outer peripheral end portion X in the inner peripheral end portion Y is opened by 5% or more, and the end surface B and the inner peripheral end portion Y are both closed.
Only the inner peripheral end portion Y is open between the surfaces on the transmission side of the separation membrane, and the outer peripheral end portion X and the end surfaces A and B are closed.
The distance from the end surface A and the end surface B of the inner end of the member for closing the end surface A and the end surface B between the permeation side surfaces of the separation membrane in the longitudinal direction of the perforated central canal. , P (A) and p (B), respectively.
The distance from the end surface A and the end surface B of the inner end of the member for closing the end surface A and the end surface B between the supply-side surfaces of the separation membrane in the longitudinal direction of the perforated central canal. , Q (A) and q (B), respectively.
The width in the longitudinal direction of the perforated central canal of the portion of the member for closing the end surface A and the end surface B of the supply-side surfaces of the separation membrane in contact with the separation membrane is r ( A) and r (B) are separation membrane elements that satisfy the following relationships.
p (A)> q (A), p (B)> q (B), and r (B) ≧ 3 mm

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