WO2022137991A1

WO2022137991A1 - Spiral membrane element

Info

Publication number: WO2022137991A1
Application number: PCT/JP2021/043592
Authority: WO
Inventors: 康秀岡▲崎▼; 康弘宇田; 摩耶木原
Original assignee: 日東電工株式会社
Priority date: 2020-12-22
Filing date: 2021-11-29
Publication date: 2022-06-30
Also published as: CN115461134A

Abstract

Provided is a spiral membrane element in which the pressure difference between the inside and the outside can be relaxed, so that the reinforcement necessary for handling etc. can be effectively performed and an outer diameter thereof can be easily adjusted with high accuracy. The spiral membrane element E according to the present invention comprises a perforated central tube 5 and a wound body R including a membrane leaf wound around the central tube 5 and a supply-side flow path material, wherein strip-shaped reinforcing portions 21 arranged along the axial direction A1 are provided at the outer peripheral side end portion of the membrane leaf and/or the supply-side flow path material, and connecting portions 22 that connect the strip-shaped reinforcing portions 21 in the circumferential direction A2 are provided in parts of the wound body R in the axial direction A1.

Description

Spiral type membrane element

The present invention relates to a spiral type membrane element (hereinafter, may be abbreviated as "membrane element") in which a band-shaped reinforcing portion is provided on the winding body.

Conventionally, in a spiral type membrane element, a flat separation membrane, a permeation side flow path material, and a supply side flow path material are wound around a perforated central tube, and an exterior material is wound around the outer periphery of the obtained winding body. It was manufactured by constructing FRP (fiber reinforced plastic). At that time, ATDs (Anti-telescoping devices, anti-telescope materials) attached to both ends of the membrane element were integrated at the time of FRP construction.

The exterior FRP is formed by, for example, winding a glass roving impregnated with a resin (a convergent body made of strands of glass filament) around the outer peripheral surface of the winding body and curing the glass roving.

However, this method requires a winding step and a curing step of the exterior material, and when winding the glass roving impregnated with the resin, it is complicated and time-consuming to wind the glass roving so as to obtain a uniform reinforcing effect. It was a process.

Therefore, there is also a technique for reinforcing the outer periphery of the film element by a method other than the exterior FRP as described above. For example, Patent Document 1 proposes a film element in which a film formed by applying an adhesive to a film having a Young's modulus of 100 kg / cm ² or more and a thickness of 100 μm or more is wound around an outer peripheral surface of a winding body.

Further, in Patent Document 2, at least one permeation side flow path material has a fiber cloth extended or connected to the outer peripheral side, and the fiber cloth is wound around the outer periphery of the cylindrical winding body. A film element in which a fiber reinforcing layer impregnated and cured with a resin is formed has been proposed. It is also disclosed that a plurality of permeation side flow path materials have a fiber cloth extended or connected to the outer peripheral side to form a fiber reinforcing layer.

Japanese Unexamined Patent Publication No. 4-11928 Japanese Unexamined Patent Publication No. 2007-268524

However, as described in Patent Document 1, in the case of a film element in which a film is wound around the outer peripheral surface of the winding body, a pressure difference between the inside and the outside of the film may occur, so that, for example, on the upstream side of the film element. In the structure provided with the seal, it was necessary to secure sufficient strength for reinforcement against the internal pressure. That is, in the structure in which the film is wound around the outer peripheral surface of the winding body, strength exceeding the reinforcement required for handling of the film element or the like is required.

Further, in the structure described in Patent Document 2, even when the fiber reinforcing layer is formed by a plurality of transmission side flow path materials, the fiber cloth impregnated with the resin is wound and cured, so that it is outside the winding body. It was difficult to adjust the diameter accurately. Further, even if the fiber reinforcing layer is formed by a plurality of permeation side flow path materials, the structure is not such that the pressure difference between the inside and the outside can be relaxed.

Therefore, an object of the present invention is to reduce the pressure difference between the inside and the outside, so that the reinforcement required for handling and the like can be effectively performed, and the outer diameter can be easily adjusted accurately. To provide the element.

The above object can be achieved by the present invention as follows.

That is, the spiral type membrane element of the present invention is a spiral type membrane element including a perforated central tube and a winding body including a membrane leaf wound around the central tube and a supply-side flow path material. , The membrane leaf and / or the outer peripheral side end of the supply side flow path material is provided with a band-shaped reinforcing portion arranged along the axial direction, and is provided in a part of the area of the winding body in the axial direction. It is characterized by having a connecting portion for connecting the strip-shaped reinforcing portion in the circumferential direction.

According to the spiral type membrane element of the present invention, since the connecting portion for connecting the strip-shaped reinforcing portion in the circumferential direction is provided in a part region in the axial direction of the winding body, the strip-shaped reinforcing portion is provided via the other portion. The pressure difference between the inside and the outside can be relaxed. As a result, a reinforcing structure that exceeds the reinforcement required for handling the membrane element or the like is not required, and a strip-shaped reinforcing portion arranged along the axial direction can provide a sufficient reinforcing effect for handling or the like. Further, since the strip-shaped reinforcing portion provided at the outer peripheral side end of the membrane leaf and / or the supply-side flow path material is connected in the circumferential direction by the connecting portion, the spacing and positional relationship of the strip-shaped reinforcing portions are adjusted. This makes it easy to adjust the outer diameter accurately. As a result, since the pressure difference between the inside and the outside can be relaxed, it is possible to effectively perform the reinforcement necessary for handling and the like, and to provide a spiral type membrane element which can easily adjust the outer diameter accurately. Can be done.

In the above, the strip-shaped reinforcing portion is preferably a strip-shaped sheet member provided at the outer peripheral side end portion of the membrane leaf and / or the supply side flow path material. By separately providing the band-shaped sheet member, the outer peripheral side end portion can be reinforced by a simple structure, and the degree of reinforcement can be easily adjusted by the material, thickness, width and the like.

Further, it is preferable that the strip-shaped reinforcing portion is a strip-shaped membrane leaf adhesive portion provided on the outer peripheral side of the outer peripheral side sealing portion of the film leaf. According to this structure, the membrane leaf adhesive portion to be the band-shaped reinforcing portion can be formed by the same method as the method of forming the outer peripheral side sealing portion on the membrane leaf. In addition, the degree of reinforcement can be adjusted by the type, thickness, width, etc. of the adhesive.

Further, it is preferable that the strip-shaped reinforcing portion is a strip-shaped resin curing portion provided on the outer peripheral side of the membrane leaf outer peripheral side sealing portion and / or on the outer peripheral side end portion of the supply side flow path material. The band-shaped reinforcing portion can also be formed by such a band-shaped resin cured portion. In addition, the degree of reinforcement can be adjusted by the type, thickness, width, etc. of the resin.

It is preferable that the connecting portion is formed by directly or via a connecting member to fix the band-shaped reinforcing portion existing on the entire circumference in two or more regions in the axial direction of the winding body. By providing the connecting portion on the entire circumference of two or more regions in the axial direction of the winding body, it is possible to maintain the outer diameter of the winding body more accurately.

Further, it is preferable to provide a removable anti-telescope material on the downstream side of the winding body. By making the anti-telescope material for suppressing the telescope removable, the amount of waste treated can be reduced and the anti-telescope material can be reused. In addition, the process of integrating the anti-telescope material with the exterior material becomes unnecessary, and the mounting process becomes simple.

According to the present invention, since the pressure difference between the inside and the outside can be relaxed, the spiral type membrane element which can effectively perform the reinforcement necessary for handling and the like and can easily adjust the outer diameter with high accuracy is provided. can do.

It is a perspective view schematically showing an example of the spiral type membrane element of this invention. It is sectional drawing which shows typically the example of the spiral type membrane element of this invention. It is a top view which shows an example of the separation membrane unit which can be used for the spiral type membrane element of this invention. It is a front view which shows an example of the separation membrane unit which can be used for the spiral type membrane element of this invention. It is a front view which shows an example of the state before laminating and winding the separation membrane unit which can be used for the spiral type membrane element of this invention. It is a partially cutaway perspective view which shows an example of a winding body in which a membrane leaf and a flow path material on a supply side are wound around a central canal. It is a perspective view which shows an example of the anti-telescope material which can be used for the spiral type membrane element of this invention. It is a top view which shows the other example of the separation membrane unit which can be used for the spiral type membrane element of this invention. It is a top view which shows the other example of the separation membrane unit which can be used for the spiral type membrane element of this invention. It is a front view which shows the other example of the anti-telescope material which can be used for the spiral type membrane element of this invention. It is a front view which shows the other example of the anti-telescope material which can be used for the spiral type membrane element of this invention. It is a front view which shows the other example of the anti-telescope material which can be used for the spiral type membrane element of this invention. It is sectional drawing which shows the main part in another example of the spiral type membrane element of this invention. It is sectional drawing which shows the main part in another example of the spiral type membrane element of this invention. It is sectional drawing which shows typically the other example of the connection part which can be adopted as the spiral type membrane element of this invention. It is a front view schematically showing another example of the separation membrane unit which can be used for the spiral type membrane element of this invention. It is sectional drawing which shows typically the other example of the connection part which can be adopted as the spiral type membrane element of this invention.

(Spiral type membrane element)
As shown in FIGS. 1A to 1B, for example, the spiral type membrane element E of the present invention includes a perforated central tube 5, a membrane leaf L wound around the central tube 5, and a supply-side flow path material 2. The winding body R and the like are provided. As shown in FIG. 3, for example, the membrane element E includes a plurality of membrane leaves L in which the transmission side flow path material 3 is interposed between the opposing separation membranes 1, and a supply side flow path that is interposed between the membrane leaves L. The material 2 is provided with a perforated central tube 5 around which the membrane leaf L and the supply-side flow path material 2 are wound, and a sealing portion for preventing mixing between the supply-side flow path and the permeation-side flow path. .. In FIG. 3, the strip-shaped reinforcing portion 21 and the connecting portion 22 are not shown for ease of understanding.

It is also possible to provide irregularities or grooves on the surface of the separation membrane 1 to form the transmission side flow path on the separation membrane 1 itself, in which case the transmission side flow path material 3 can be omitted.

In this embodiment, as shown in FIG. 3, an example is shown in which the sealing portion includes both ends sealing portion 11 and the outer peripheral side sealing portion 12. Of the sealing portions, the both end sealing portions 11 are formed by sealing the two side ends of the film leaf L on both sides in the axial direction A1 with an adhesive. The outer peripheral side sealing portion 12 is formed by sealing the end portion of the outer peripheral side (direction of arrow A3) of the film leaf L with an adhesive.

Further, in the present invention, as shown in FIG. 3, it is preferable to have a central sealing portion 13 in which the perforated central tube 5 and the base end portion of the membrane leaf L are sealed with an adhesive. The membrane element of the present embodiment has a winding body R in which the membrane leaf L and the supply-side flow path material 2 are wound around the central tube 5 via such a central sealing portion 13.

The winding body R can be manufactured by, for example, the steps shown in FIGS. 2A to 2C. 2A is a plan view of the separation membrane unit U, FIG. 2B is a front view of the separation membrane unit U, and FIG. 2C is a front view showing a state before laminating and winding the separation membrane unit U.

First, as shown in FIGS. 2A and 2B, a material in which the supply side flow path material 2 is arranged while the separation membrane 1 is folded in half and a permeation side flow path material 3 are stacked, and both ends sealing portion 11 and the outer periphery thereof are stacked. The separation membrane unit U is prepared by applying the

adhesives

4 and 6 for forming the side sealing portion 12 to both ends of the transmission side flow path material 3 in the axial direction A1 and the tip of the winding. At this time, a protective tape may be attached to the crease portion of the separation membrane 1.

The

adhesives

4 and 6 are not particularly limited, and conventionally known adhesives can be adopted. Specifically, any conventionally known adhesive such as a urethane-based adhesive or an epoxy-based adhesive can be used.

Next, as shown in FIG. 2C, the same number of separation membrane units U as the membrane leaf L are laminated on the transmission side flow path material 3 having a portion extended from the others, and the separation membrane unit U is laminated. Prepare your body. At this time, the central side sealing portion 13 can be formed by applying the adhesive to both ends of the extension portion of the lowermost permeation side flow path material 3 in the axial direction A1.

Next, as shown in FIG. 2C, the perforated central tube 5 is rotated in the direction of the arrow, and the plurality of separation membrane units U are wound around the central canal 5. At this time, the

adhesives

4 and 6 adhere the opposing separation membrane 1 and the permeation side flow path material 3 to form a membrane leaf L having both end sealing portions 11 and outer peripheral side sealing portions 12. To.

As a result, as shown in FIG. 3, a winding body R in which the membrane leaf L and the supply-side flow path material 2 are wound around the central tube 5 is formed. The wound body R after sealing may be trimmed at both ends in order to adjust the length in the axial direction A1. For example, in a general 8-inch diameter spiral type membrane element, about 15 to 30 sets of membrane leaf L are wound.

In the conventional membrane element E, an upstream end member such as a seal carrier is provided on the upstream side of the winding body R, and a downstream end member such as an anti-telescope material is provided on the downstream side of the winding body R. It is provided integrally. However, in the membrane element E of the present invention, it is not necessary to provide the upstream end member integrated with the winding body R. Further, as shown in FIG. 7A and the like, the anti-telescope material 25 is not integrated with the winding body R, but preferably includes a removable anti-telescope material 25.

(Reinforced structure)
The present invention is arranged along the axial direction A1 at the outer peripheral side (direction of arrow A3) end of the film leaf L and / or the supply side flow path material 2, as shown in FIGS. 1A to 1B, for example. The band-shaped reinforcing portion 21 is provided, and has a connecting portion 22 for connecting the band-shaped reinforcing portion 21 in the circumferential direction A2 in a part of the region of the winding body R in the axial direction A1. In the illustrated example, the connecting portion 22 is provided in two regions of the winding body R in the axial direction A1.

Since the connecting portion 22 for connecting the strip-shaped reinforcing portion 21 in the circumferential direction A2 is provided in a part of the region of the winding body R in the axial center direction A1, the supply liquid is supplied through the portion where the connecting portion 22 does not exist. Since the flow of the above is generated, the pressure difference between the inside and the outside of the band-shaped reinforcing portion 21 can be relaxed. As a result, a reinforcing structure that exceeds the reinforcement required for handling of the membrane element E is not required, and the strip-shaped reinforcing portion 21 arranged along the axial direction A1 has a sufficient reinforcing effect (strength and bending) for handling and the like. Rigidity etc.) can be obtained. Further, since the strip-shaped reinforcing portion 21 provided at the outer peripheral side (arrow A3 side) end of the membrane leaf L and / or the supply side flow path material 2 is connected to the circumferential direction A2 by the connecting portion 22, the strip-shaped reinforcing portion 21 is formed. By adjusting the spacing and positional relationship of the reinforcing portions 21, it becomes easy to accurately adjust the outer diameter.

The strip-shaped reinforcing portion 21 is connected by the connecting portion 22, and the plurality of strip-shaped reinforcing portions 21 before the connection can change the mutual spacing and positional relationship.

The band-shaped reinforcing portion 21 does not have to cover the entire circumference of the winding body R, but it is preferable that the band-shaped reinforcing portion 21 covers the entire circumference of the winding body R. When the strip-shaped reinforcing portion 21 is provided on the membrane leaf L or the supply-side flow path material 2, the same number as the total number of the membrane leaf L or the supply-side flow path material 2 may not be provided (for example, the total number of the membrane leaf L). It may be half or the like), and it is preferable to provide the same number of strip-shaped reinforcing portions 21 as the total number of the membrane leaf L or the supply side flow path material 2.

(Strip-shaped reinforcement)
In the present embodiment, as shown in FIGS. 1A to 1B, an example is shown in which the band-shaped reinforcing portion 21 is a band-shaped sheet member 21a provided at the outer peripheral side (arrow A3 side) end of the membrane leaf L. Such a strip-shaped sheet member 21a can be provided at the outer peripheral side (arrow A3 side) end of the supply side flow path material 2, and can also be provided on both the membrane leaf L and the supply side flow path material 2. It is possible.

As the sheet member 21a, a resin sheet is preferably used, and examples thereof include a sheet made of a polyolefin resin such as polypropylene and polyethylene, a polyester resin such as polyethylene terephthalate and polyethylene naphthalate, and a polyamide resin. Among these resins, polyethylene terephthalate, polypropylene, polyethylene and the like are preferable.

It is also possible to use a fiber cloth, a porous sheet, etc. as long as it has sufficient bending rigidity. Further, those having sufficient bending rigidity by impregnating them with a resin or the like can also be used.

As the sheet member 21a, sheets of various thicknesses composed of a single layer or multiple layers can be used. The thickness of the sheet member 21a (total thickness in the case of a multilayer structure) is preferably 0.1 to 1 mm, more preferably 0.3 to 0.5 mm from the viewpoint of ensuring appropriate strength.

The length of the sheet member 21a in the axial direction A1 does not have to correspond to the total length of the winding body R, but from the viewpoint of ensuring the strength required for handling and the like, the total length of the winding body R is 20. It is preferably ~ 100%, more preferably 60-100%, and most preferably 100%.

The width of the seat member 21a in the circumferential direction A2 is preferably a width in which the seat members 21a overlap each other, but may be a width such that the seat members 21a are separated from each other. Specifically, when the outer peripheral length of the wound body R is divided by the number of the sheet members 21a to be 100%, the width of the sheet member 21a in the circumferential direction A2 is, for example, 70 to 200%, which is preferable. Is 100-150%.

As a method of providing the sheet member 21a at the outer peripheral side (arrow A3 side) end of the membrane leaf L or the supply side flow path material 2, the sheet member 21a may be provided after the winding body R as shown in FIG. 3 is formed. Although it is possible, it is preferable to provide the sheet member 21a before forming the winding body R from the viewpoint of simplifying the manufacturing process.

For example, the sheet member 21a is adhered, heat-sealed, and super-adhered to the outer peripheral side end portion of the supply side flow path material 2, the separation film 1, or the transmission side flow path material 3 of the separation membrane unit U shown in FIGS. 2B to 2C. Examples thereof include a method of fixing by sonic fusion or the like. It is also possible to bond the sheet member 21a to the membrane leaf L by using the

adhesives

4 and 6 that bond the separation membrane 1 of the separation membrane unit U and the transmission side flow path material 3.

In the example shown in FIG. 1B, the sheet member 21a is fixed to the separation membrane 1 existing outside the outer peripheral side (arrow A3 side) end of the membrane leaf L, but the outer peripheral side (arrow A3 side) of the membrane leaf L. It may be fixed to the inside of the end. Further, even when the material 2 is provided at the outer peripheral side (arrow A3 side) end of the supply side flow path material 2, the sheet member 21a can be fixed to the outside or the inside thereof.

(Another embodiment of the band-shaped reinforcing portion)
(1) In the above embodiment, the example in which the sheet member 21a is provided as the strip-shaped reinforcing portion 21 is shown, but the strip-shaped reinforcing portion 21 can also be formed by the membrane leaf L. For example, as shown in FIG. 5A, the separation film 1 is extended to the outer peripheral side (arrow A3 side) of the adhesive 6 of the separation film unit U corresponding to FIG. 2A, and the same or different adhesive as the adhesive 6 is adhered to the surface thereof. The band-shaped reinforcing portion 21 can be formed by applying the agent 21b and adhering the separation films 1 to each other in the same manner as the adhesive 6. The permeation side flow path material 3 may be extended to the outer peripheral side together with the separation membrane 1.

As such an adhesive 21b, one having higher rigidity after curing than the urethane-based adhesive used for the adhesive 6 is preferable, and an epoxy-based adhesive or the like is preferable.

Further, when the adhesive 21b is applied, a fiber cloth may be laminated for reinforcement to form a fiber reinforcement structure. Examples of the fiber cloth include non-woven fabric, woven cloth, knitted fabric, mesh sheet and the like. By adopting such a fiber reinforced structure, the thickness thereof can be made thicker than the portion bonded with the adhesive 6. That is, the band-shaped reinforcing portion 21 formed by the film leaf L can have a portion thicker than the thickness of the normal film leaf L bonded with the adhesive 6.

Further, the width of the band-shaped reinforcing portion 21 formed of the adhesive 21b in the circumferential direction A2 is preferably a width in which the band-shaped reinforcing portions 21 overlap each other, but the width is such that the band-shaped reinforcing portions 21 are separated from each other. There may be. Specifically, when the length obtained by dividing the outer peripheral length of the wound body R by the number of the strip-shaped reinforcing portions 21 is 100%, the width of the strip-shaped reinforcing portions 21 in the circumferential direction A2 is, for example, 70 to 200%. , Preferably 100-150%.

In the illustrated example, the adhesive 6 and the adhesive 21b are applied separately, but both may be applied without a gap.

(2) In the above embodiment, an example in which the sheet member 21a is provided as the strip-shaped reinforcing portion 21 is shown. However, as shown in FIG. 5B, for example, the supply-side flow path material 2 extended to the outer peripheral side (arrow A3 side). It may be a band-shaped resin curing portion 21c provided at the outer peripheral side end portion. Such a strip-shaped resin curing portion 21c can be provided on the outer peripheral side of the outer peripheral side sealing portion 12 of the membrane leaf L, or can be provided on both the membrane leaf L and the supply side flow path material 2. Is.

In the illustrated example, the resin curing portion 21c is formed with respect to the supply-side flow path material 2 before winding, but the extended supply-side flow path material 2 has a curable end on the outer peripheral side. The resin cured portion 21c may be formed by impregnating and curing the resin, and this may be used for the separation membrane unit U. It is also possible to provide the band-shaped resin curing portion 21c after winding the film leaf L.

Further, instead of the supply side flow path material 2, the separation membrane 1 or the transmission side flow path material 3 is extended to the outer peripheral side, and a curable resin is applied and cured to form the resin curing portion 21c. By using this for the separation membrane unit U, it becomes possible to provide the strip-shaped reinforcing portion 21 on the membrane leaf L.

(Connecting part)
In this embodiment, as shown in FIGS. 1A to 1B, an example is shown in which the connecting portion 22 is an adhesive tape 22a provided in two regions of the winding body R in the axial direction A1. That is, an example of the connecting portion 22 in which the band-shaped reinforcing portion 21 existing on the entire circumference is fixed via the connecting member in two or more regions in the axial direction A1 of the winding body R is shown.

Although it is possible to provide the connecting portion 22 at one location in the axial direction A1 of the winding body R, it is preferable to provide it at two or more locations, and it is also possible to provide it at three or more locations.

The connecting portion 22 is provided in a part of the region of the winding body R in the axial center direction A1, but the total width of the connecting portion 22 is 1 to 1 with respect to the total length of the winding body R in the axial center direction A1. It is preferably provided in a region of 50%, more preferably in a region of 3 to 30%.

The adhesive tape 22a preferably has water resistance, the base material is an OPP (Oriented PolyPropylene) -based or PET-based, PE-based, or polyimide-based resin, and the adhesive is an acrylic-based or rubber-based adhesive. It is preferable to have.

The width of one of the adhesive tapes 22a is preferably 50 to 100 mm from the viewpoint of obtaining sufficient connection strength and a stable shape. The adhesive tape 22a is preferably attached to all the band-shaped reinforcing portions 21.

In the method of providing the adhesive tape 22a as the connecting portion 22 on the band-shaped reinforcing portion 21, the adhesive tape 22a is attached in a state where the strip-shaped reinforcing portion 21 is uniformly arranged on the outer circumference while adjusting the outer diameter of the winding body R. You just have to wear it. At that time, since the band-shaped reinforcing portion 21 has a rigidity of a certain level or higher, complicated operations are less likely to be required.

It is also possible to use a tape provided with a heat-sealing layer on the base material instead of the adhesive tape 22a to fix the band-shaped reinforcing portion 21 by heat-sealing.

(Another embodiment of the connecting portion)
As the connecting portion 22, a tape other than the adhesive tape 22a can also be used. That is, the connecting portion 22 may be any one that connects the strip-shaped reinforcing portion 21 in the circumferential direction in a part of the region of the winding body R in the axial center direction A1, and the strip-shaped reinforcing portion 21 may be directly connected or via a connecting member. Any connecting portion 22 can be adopted as long as it is fixed.

(1) For example, as shown in FIG. 8A, the connecting portion 22 is formed by using the double-sided adhesive tape 22b attached to the strip-shaped reinforcing portion 21 in a part of the region of the winding body R in the axial direction A1. You can also. The double-sided adhesive tape 22b is attached to one of the strip-shaped reinforcing portions 21 to be attached after or before winding the winding body R, and after winding, the outside of the winding body R is attached. While adjusting the diameter, it may be attached to the other strip-shaped reinforcing portion 21.

The double-sided adhesive tape 22b preferably has a width of 5 to 50 mm in the circumferential direction from the viewpoint of obtaining sufficient fixing strength. As a part of the axial center direction A1 where the double-sided adhesive tape 22b is provided, it is preferable that the double-sided adhesive tape 22b is provided in a region of 1 to 50% as the total width of the axial center direction A1 of the double-sided

adhesive tape

22b, and 3 to 30%. It is more preferable to be provided in the area of.

The double-sided adhesive tape 22b preferably has water resistance, preferably a non-woven fabric-based or film-based base material, and an acrylic-based or rubber-based adhesive.

(2) Further, as shown in FIG. 8B, the adhesive 22c is applied to the strip-shaped reinforcing portion 21 formed on the separation membrane unit U instead of the double-sided adhesive tape 22b, and the strip-shaped reinforcing portion is applied by the adhesive 22c. It is also possible to form a connecting portion 22 for connecting 21. At that time, the outer diameter of the winding body R may be adjusted while winding the winding body R, and the band-shaped reinforcing portions 21 may be adhered to each other.

As the adhesive 22c, the same adhesive as that of the adhesive 4 can be used, but the adhesive 4 is first solidified after the winding body R is wound, and in that state, heat-sealing property and the like can be used later. It is also possible to bond with the adhesive 22c of.

(3) Further, as shown in FIG. 8C, the strip-shaped sheet 22d and the adhesive 22e can be used to form the connecting portion 22 for connecting the strip-shaped reinforcing portion 21. As the band-shaped sheet 22d, a sheet having a lower rigidity than the band-shaped sheet member 21a can also be used, and a resin sheet can be preferably used.

(Supply side flow path material)
The supply-side flow path material 2 generally has a role of securing a gap for evenly supplying the fluid to the film surface. As such a supply-side flow path material 2, for example, a net, knitting, an uneven processing sheet, or the like can be used, and a material having a maximum thickness of about 0.1 to 3 mm can be used as needed. In such a supply-side flow path material 2, it is preferable that the pressure loss is low, and it is preferable that the material 2 produces an appropriate turbulent flow effect. Further, although the flow path material is installed on both sides of the separation membrane 1, it is common to use different flow path materials as the supply side flow path material 2 on the supply liquid side and the permeation side flow path material 3 on the permeation liquid side. Is the target. It is preferable to use a net-like flow path material having a coarse and thick mesh in the supply side flow path material 2, while using a fine woven fabric or knitted flow path material in the transmission side flow path material 3.

The supply side flow path material 2 is provided on the inner surface side of the above-mentioned double-folded composite semipermeable membrane when an RO membrane or an NF membrane is used in applications such as seawater desalination and wastewater treatment. As the structure of the flow path material 2 on the supply side, generally, a network structure in which linear objects are arranged in a grid pattern can be preferably used.

The constituent material is not particularly limited, but polyethylene, polypropylene, etc. are used. These resins may contain a bactericidal agent or an antibacterial agent. The thickness of the supply-side flow path material 2 is generally 0.2 to 2.0 mm, preferably 0.5 to 1.0 mm. If the thickness is too thick, the amount of permeation decreases with the amount of membrane that can be accommodated in the membrane element, and conversely, if it is too thin, contaminants tend to adhere, so that the permeation performance tends to deteriorate.

In particular, in the present invention, by combining with the supply side flow path material 2 having a diameter of 0.6 to 1.0 mm, contaminants are less likely to be deposited and biofouling is less likely to occur. The decrease can be suppressed.

(Central canal)
The central canal 5 may be any as long as it has an opening 5a around the tube, and any conventional one can be used. Generally, when used for seawater desalination, wastewater treatment, etc., the permeated water that has passed through the separation membrane 1 invades into the central canal 5 through the hole in the wall surface and forms a permeation side flow path. The length of the central tube 5 is generally longer than the axial length of the winding body R, but the central tube 5 having a connected structure such as being divided into a plurality of parts may be used. The material constituting the central tube 5 is not particularly limited, but a thermosetting resin or a thermoplastic resin is used.

That is, the central tube 5 extends only to the downstream side of the winding body R, extends to the upstream and downstream sides of the winding body R, or extends only to the upstream side of the winding body R. Any of the cases may be used. However, when the detachable anti-telescope material 25 is provided on the downstream side of the winding body R, it is preferable that the central tube 5 extends at least on the downstream side of the winding body R.

In the example of the membrane element E shown in FIG. 1, the central canal 5 projects to the upstream side and the downstream side with substantially the same length with respect to the winding body R, but as shown in FIG. 7A, the central canal 5 protrudes. When extending only to the downstream side of the winding body R, it is more preferable because peripheral parts used in the conventional structure can be shared.

(Transmission side flow path material)
The permeation side flow path material 3 is interposed between the separation membranes 1 facing each other in the membrane leaf L as shown in FIG. 3 when the RO membrane or the NF membrane is used in applications such as seawater desalination and wastewater treatment. It is provided as follows. The permeation side flow path material is required to support the pressure applied to the membrane from the back surface of the membrane and to secure a flow path for the permeation liquid.

In the present invention, in order to secure such a function, it is preferable that the permeation side flow path material is formed by the tricot knit, and it is more preferable that the tricot knit is resin-reinforced or fused after the knit is formed. ..

Examples of the constituent yarns of the permeation side flow path material include polyesters such as polyethylene terephthalate and polyethylene naphthalate, and polyolefins such as polyethylene and polypropylene. Of these, polyethylene terephthalate is particularly preferably used from the viewpoint of processability and productivity.

When reinforcing the resin after forming the knit, there are methods such as impregnating the fiber with the resin and curing it, or coating the fiber surface with the resin and curing it. Examples of the resin used for reinforcement include melamine resin and epoxy resin.

The constituent yarn of the permeation side flow path material may be monofilament or multifilament, but a tricot knit is formed by the constituent yarn having a certain thickness. Among the tricot knits, half knits and double denby knits, which have a clear structure of linearly continuous grooves, are preferable.

The thickness of the permeation side flow path material is preferably 0.10 to 0.40 mm, more preferably 0.15 to 0.35 mm, and even more preferably 0.20 to 0.30 mm. When the thickness is 0.10 mm or more, a sufficient flow path is secured and the pressure loss of the permeated liquid can be reduced. Further, when the thickness is 0.40 mm or less, the effective membrane area of the separation membrane in the membrane element becomes large, and it becomes easy to increase the flow rate of the permeate. The constituent yarn of the permeation side flow path material is preferably 0.1 to 0.15 mm in order to form a tricot knit having the above thickness.

In the present invention, the width of the linearly continuous grooves in the tricot knitted fabric is preferably 0.05 to 0.40 mm, more preferably 0.10 to 0.28 mm. If the width of the groove is less than 0.05 mm, the pressure loss of the permeate tends to be too large, and if the width of the groove exceeds 0.40 mm, the inhibition rate due to the deformation of the composite semipermeable membrane tends to decrease. May be.

Note that the width of the linearly continuous grooves in the tricot knitted fabric refers to the average value between the widest part and the narrowest part of the adjacent loops. From the microscope photograph, the above average values can be measured for 10 pairs of loops, and the average values of the 10 loop pairs can be further averaged to obtain the width of continuous grooves.

The direction in which the permeation side flow path material is arranged in the membrane element may be any, but it is preferable that the direction of the linearly continuous groove is wound in the direction along the circumferential direction.

(Separation membrane)
As the separation membrane 1, various porous membranes can be used, but a composite semipermeable membrane having a separation functional layer on the surface of the porous support is preferable. The porous support preferably has a polymer porous layer on one side of the nonwoven fabric layer. The thickness of the separation membrane, particularly the composite semipermeable membrane, is preferably about 70 to 160 μm, more preferably 85 to 130 μm.

Such composite transpermeable membranes are called RO (reverse osmosis) membranes, NF (nanofiltration) membranes, and FO (normal permeation) membranes depending on their filtration performance and treatment method, and are used for ultrapure water production and seawater desalination. , Can be used for desalination treatment of brackish water, reuse treatment of wastewater, etc.

Examples of the separation functional layer include polyamide-based, cellulose-based, polyether-based, and silicon-based separation functional layers, but those having a polyamide-based separation functional layer are preferable. The polyamide-based separation functional layer is generally a homogeneous film having no visible pores and has a desired ion separation ability. The separation functional layer is not particularly limited as long as it is a polyamide-based thin film that is difficult to peel off from the polymer porous layer, but for example, a polyfunctional amine component and a polyfunctional acid halide component are interfaced on the porous support membrane. A polymerized polyamide-based separation functional layer is well known.

The method for forming the polyamide-based separation functional layer on the surface of the polymer porous layer is not particularly limited, and any known method can be used. For example, a method such as an interfacial polymerization method, a phase separation method, and a thin film coating method can be mentioned, but in the present invention, the interfacial polymerization method is particularly preferably used. In the interfacial polymerization method, for example, a polymer porous layer is coated with an amine aqueous solution containing a polyfunctional amine component, and then an organic solution containing a polyfunctional acid halide component is brought into contact with the surface coated with the amine aqueous solution to cause interfacial polymerization. A method of forming a skin layer.

The polyfunctional amine component contained in the amine aqueous solution is a polyfunctional amine having two or more reactive amino groups, and examples thereof include aromatic, aliphatic, and alicyclic polyfunctional amines. Examples of the aromatic polyfunctional amine include m-phenylenediamine, p-phenylenediamine, o-phenylenediamine, 1,3,5-triaminobenzene, 1,2,4-triaminobenzene, and 3,5-. Examples thereof include diaminobenzoic acid, 2,4-diaminotoluene, 2,6-diaminotoluene, N, N'-dimethyl-m-phenylenediamine, 2,4-diaminoanisole, amidol, and xylylenediamine. Examples of the aliphatic polyfunctional amine include ethylenediamine, propylenediamine, tris (2-aminoethyl) amine, n-phenyl-ethylenediamine and the like. Examples of the alicyclic polyfunctional amine include 1,3-diaminocyclohexane, 1,2-diaminocyclohexane, 1,4-diaminocyclohexane, piperazine, 2,5-dimethylpiperazine, 4-aminomethylpiperazine and the like. Be done. These polyfunctional amines may be used alone or in combination of two or more. In particular, in the present invention, when a high inhibition rate is required in the reverse osmosis membrane performance, it is preferable to use m-phenylenediamine as a main component, which can obtain a highly dense separation functional layer, and a high Lux retention in the NF membrane performance. When determining the rate, it is preferable to use piperazine as the main component.

The polyfunctional acid halide component contained in the organic solution is a polyfunctional acid halide having two or more reactive carbonyl groups, and examples thereof include aromatic, aliphatic, and alicyclic polyfunctional acid halides. Examples of the aromatic polyfunctional acid halide include trimethic acid trichloride, terephthalic acid dichloride, isophthalic acid dichloride, biphenyldicarboxylic acid dichloride, naphthalenedicarboxylic acid dichloride, benzenetrisulfonic acid trichloride, benzenedisulfonic acid dichloride, and chlorosulfonylbenzene. Examples thereof include dicarboxylic acid dichloride. Examples of the aliphatic polyfunctional acid halide include propanedicarboxylic acid dichloride, butanedicarboxylic acid dichloride, pentandicarboxylic acid dichloride, propanthricarboxylic acid trichloride, butanetricarboxylic acid trichloride, pentantricarboxylic acid trichloride, glutalyl halide, and hydrangea. Poil halide and the like can be mentioned. Examples of the alicyclic polyfunctional acid halide include cyclopropanetricarboxylic acid trichloride, cyclobutanetetracarboxylic acid tetrachloride, cyclopentanetricarboxylic acid trichloride, cyclopentanetetracarboxylic acid tetrachloride, cyclohexanetricarboxylic acid trichloride, and tetrahydro. Examples thereof include furantetracarboxylic acid tetrachloride, cyclopentane dicarboxylic acid dichloride, cyclobutane dicarboxylic acid dichloride, cyclohexanedicarboxylic acid dichloride, tetrahydrofurandicarboxylic acid dichloride and the like. These polyfunctional acid halides may be used alone or in combination of two or more. In order to obtain a skin layer with high salt blocking performance, it is preferable to use an aromatic polyfunctional acid halide. Further, it is preferable to use a trivalent or higher valent polyfunctional acid halide for at least a part of the polyfunctional acid halide component to form a crosslinked structure.

The organic solvent containing the polyfunctional acid halide is not particularly limited as long as it has low solubility in water and dissolves the polyfunctional acid halide component without deteriorating the porous support film. For example, cyclohexane. Saturated hydrocarbons such as heptane, octane and nonane, halogen-substituted hydrocarbons such as 1,1,2-trichlorotrifluoroethane and the like can be mentioned. It is preferably a saturated hydrocarbon having a boiling point of 300 ° C. or lower, more preferably 200 ° C. or lower.

Additives for the purpose of improving various performances and handleability may be added to the amine aqueous solution or the organic solution. Examples of the additive include polymers such as polyvinyl alcohol, polyvinylpyrrolidone and polyacrylic acid, polyhydric alcohols such as sorbitol and glycerin, and surfactants such as sodium dodecylbenzene sulfonate, sodium dodecyl sulfate and sodium lauryl sulfate. , Basic compounds such as sodium hydroxide, trisodium phosphate, and triethylamine that remove hydrogen halide generated by polymerization, acylation catalysts, and solubility parameters described in JP-A-8-224452 (cal). / Cm ³ ) ^1/2 compound and the like can be mentioned.

A coating layer composed of various polymer components may be provided on the exposed surface of the separation function layer. The polymer component is not particularly limited as long as it is a polymer that does not dissolve the separation functional layer and the porous support film and does not elute during the water treatment operation. For example, polyvinyl alcohol, polyvinylpyrrolidone, hydroxypropyl cellulose, polyethylene. Glycol and saponified polyethylene-vinyl acetate copolymer and the like can be mentioned. Of these, polyvinyl alcohol is preferably used, and in particular, polyvinyl alcohol having a saponification degree of 99% or more is used, or polyvinyl alcohol having a saponification degree of 90% or more is crosslinked with the polyamide resin of the skin layer. It is preferable to have a structure that does not easily elute during water treatment. By providing such a coating layer, the charge state of the film surface is adjusted and hydrophilicity is imparted, so that the adhesion of contaminants can be suppressed, and the Lux holding effect is further achieved by the synergistic effect with the present invention. Can be further enhanced.

The non-woven fabric layer used in the present invention is not particularly limited as long as it imparts appropriate mechanical strength while maintaining the separation performance and permeation performance of the composite semipermeable membrane, and a commercially available non-woven fabric is used. be able to. As this material, for example, a material made of polyolefin, polyester, cellulose or the like is used, and a material obtained by mixing a plurality of materials can also be used. In particular, polyester is preferably used in terms of moldability. Further, a long-fiber nonwoven fabric or a short-fiber nonwoven fabric can be used as appropriate, but a long-fiber nonwoven fabric can be preferably used from the viewpoint of fine fluffing that causes pinhole defects and the uniformity of the film surface.

The polymer porous layer is not particularly limited as long as it can form the polyamide-based separation functional layer, but is usually a microporous layer having a pore size of about 0.01 to 0.4 μm. Examples of the material for forming the microporous layer include polysulfone, polyaryletherketone exemplified for polyethersulfone, polyimide, polyvinylidene fluoride, and the like. In particular, it is preferable to form a polymer porous layer using polysulfone or polyarylether sulfone from the viewpoint of chemical, mechanical and thermal stability.

(Anti-telescope material)
In the present invention, as shown in FIG. 7, it is preferable to provide the anti-telescope material 25 on the downstream side of the winding body R, and it is preferable to provide the removable anti-telescope material 25.

The anti-telescope material 25 preferably has at least an outer peripheral side obstruction plate 29 arranged on the downstream side near the outer periphery of the winding body R, but as shown in FIG. 4, near the outer periphery of the winding body R. It is more preferable to provide the outer peripheral side obstruction plate 29 arranged on the downstream side and the inner peripheral side obstruction plate 27 arranged on the downstream side near the inner circumference of the winding body R. Here, the vicinity of the inner circumference of the winding body R refers to any position within the range of 0 to 30% from the inner circumference when the distance between the outer circumference and the inner circumference of the winding body R is 100%. , Near the outer circumference refers to any position within a range of 70% or more from the inner circumference.

The outer diameter of the outer peripheral side baffle plate 29 may be larger than the outer diameter of the film element E, and is preferably 98 to 100.0% with respect to the inner diameter of the pressure vessel to be accommodated, 99 to 100. It is more preferably 0% and most preferably 100.0%. By setting the outer diameter of the outer peripheral side baffle plate 29 as such, the low-concentration concentrated liquid flowing outside the band-shaped reinforcing portion 21 can be more effectively mixed and stirred and supplied to the next stage.

As shown in FIG. 4, the anti-telescope material 25 of the present embodiment shows an example having an annular portion 26 and ribs 28 extending radially from the annular portion 26. The number of ribs 28 is not particularly limited, but 4 to 20 are preferable, and 8 to 16 are more preferable, from the viewpoint of ensuring sufficient flow path and strength while suppressing the telescope.

It is preferable that the anti-telescope material 25 is detachably attached to the central tube 5 extending to the downstream side of the winding body R. Therefore, the annular portion 26 has an inner peripheral surface into which the central canal 5 can be fitted. The rib 28 can prevent the winding body R from being deformed in a telescope shape by abutting the end surface on the upstream side of the rib 28 on the downstream end surface of the winding body R.

(Another Embodiment of Anti-Telescope Material)
In the previous embodiment, an example having the annular portion 26 and the rib 28 extending radially from the annular portion 26 has been shown, but as shown in FIG. 6A, the inner peripheral side of the rib 28 abuts on the central canal 5 and the like. It is possible to omit 26.

Further, as shown in FIG. 6B, the outer peripheral side obstruction plate 29 arranged on the downstream side near the outer peripheral side of the winding body R and the inner peripheral side obstruction plate arranged on the downstream side near the inner circumference of the winding body R. 27 may be formed by a continuous plate-shaped portion, and a plurality of openings may be provided in the plate-shaped portion.

Further, as shown in FIG. 6C, the inner peripheral side obstruction plate 27 is omitted, a sealing material (for example, an O-ring) is provided on the outer peripheral side of the outer peripheral side obstruction plate 29, and the anti-telescope material 25 is provided on the inner surface of the pressure vessel. The outer periphery may be in close contact.

The interconnector 35 may be integrated with the anti-telescope material 25 so that the interconnector 35 has a function as the anti-telescope material 25. For example, as shown in FIG. 7B, instead of providing the annular portion 26, an inner peripheral side obstruction plate 27 is provided around the interconnector 35, the inner peripheral end of the rib 28 is arranged near the outer periphery of the central tube 5, and the rib 28 is provided. The structure may be such that the outer peripheral side baffle plate 29 is provided via the above.

(Another Embodiment of Spiral Membrane Elements)
In the above description, the most preferable embodiment of the present invention has been described. However, the present invention is not limited to the embodiment, and various modifications can be made within substantially the same range as the technical idea described in the claims of the present invention.

That is, in the above embodiment, as shown in FIGS. 2A to 2C, the permeation side flow path material 3 is superposed on the separation membrane 1 folded in half so as to sandwich the supply side flow path material 2. The example of applying the

adhesives

4 and 6 has been described. However, in the present invention, it is also possible to superimpose the separation membrane 1 folded in half on the permeation side flow path material 3 and apply the

adhesives

4 and 6 on it. Further, instead of the separation film 1 folded in half, two separation films 1 may be used to sandwich the supply side flow path material 2 and a sealing portion may be provided on the winding start side as well. Further, the continuous separation membrane 1 may be used to eliminate the need for the outer peripheral side sealing portion 12.

(Use of spiral type membrane element)
When the membrane element of the present invention is used, it is generally housed in a pressure vessel (vessel), and the supply liquid is supplied from one end face side of the membrane element E. The supplied liquid flows along the supply-side flow path material 2 in a direction parallel to the axial direction A1 of the central tube 5, and is discharged as a concentrated liquid from the other end surface side of the membrane element E. Further, the permeated liquid that has permeated the separation membrane 1 in the process of flowing along the supply side flow path material 2 flows along the permeation side flow path material and then flows into the inside of the central tube 5 from the opening 5a. , Is discharged from the end of this central tube 5.

In the membrane element of the present invention, the supply liquid (bypass flow) flows outside the band-shaped reinforcing portion 21, but by adjusting the outer diameter of the membrane element to be substantially equal to the inner diameter of the pressure vessel, the bypass flow occurs. Can be reduced.

From the viewpoint of reducing such a bypass flow, it is preferable that the shape of the band-shaped reinforcing portion 21 has a shape along the inner peripheral surface of the pressure vessel, that is, an arc-shaped cross section. Further, it is preferable that at least when the membrane element is housed in the pressure vessel, the strip-shaped reinforcing portion 21 can be deformed so as to have an arc-shaped cross section. Examples of the band-shaped reinforcing portion 21 that enables such modification include those having a bending rigidity in the circumferential direction A2 lower than the bending rigidity in the axial direction A1. Such properties can be achieved, for example, with fiber reinforced resins containing fibers or fiber cloths.

When a plurality of film elements E are used, the film elements E are connected to each other by an interconnector 35, for example, as shown in FIG. 7A. When the anti-telescope material 25 shown in FIG. 4 is provided, the outer peripheral side obstruction plate 29 arranged on the downstream side near the outer periphery of the winding body R has a shape in which the outer periphery thereof is in contact with the inner surface of the pressure vessel. As a result, the amount of concentrated liquid flowing in the gap between the outer peripheral side obstruction plate 29 and the inner surface of the pressure vessel can be reduced as much as possible, and the stirring / mixing effect can be further enhanced.

According to the present invention, since the pressure difference between the inside and the outside can be relaxed, the spiral type membrane element which can effectively perform the reinforcement necessary for handling and the like and can easily adjust the outer diameter with high accuracy is provided. can do. Therefore, the conventional exterior FRP can be omitted, which is advantageous for recycling.

1: Separation membrane 2: Supply side flow path material 3: Permeation side flow path material 5: Central tube 21: Band-shaped reinforcing part 21a: Band-shaped sheet member 22: Connecting part 22a: Adhesive tape 25: Anti-telescope material A1: Shaft Center direction A2: Circumferential direction A3: Outer peripheral direction E: Spiral type membrane element R: Winder L: Membrane leaf

Claims

A spiral membrane element comprising a perforated central tube and a wound body including a membrane leaf wound around the central tube and a supply-side flow path material.
A band-shaped reinforcing portion arranged along the axial direction is provided at the outer peripheral side end portion of the membrane leaf and / or the supply side flow path material.
A spiral type membrane element having a connecting portion for connecting the strip-shaped reinforcing portion in the circumferential direction in a part of a region in the axial direction of the winding body.
The spiral type membrane element according to claim 1, wherein the strip-shaped reinforcing portion is a strip-shaped sheet member provided at the outer peripheral side end portion of the membrane leaf and / or the supply side flow path material.
The spiral type membrane element according to claim 1, wherein the strip-shaped reinforcing portion is a strip-shaped membrane leaf adhesive portion provided on the outer peripheral side of the outer peripheral side sealing portion of the membrane leaf.
The spiral type according to claim 1, wherein the strip-shaped reinforcing portion is a strip-shaped resin curing portion provided on the outer peripheral side of the membrane leaf outer peripheral side sealing portion and / or on the outer peripheral side end portion of the supply side flow path material. Membrane element.
The connecting portion is any one of claims 1 to 4 in which the strip-shaped reinforcing portion existing on the entire circumference is fixed directly or via a connecting member in two or more regions in the axial direction of the winding body. Spiral type membrane element described in the section.
The spiral membrane element according to any one of claims 1 to 5, wherein a removable anti-telescope material is provided only on the downstream side of the winding body.