JP4936435B2 - Spiral type membrane element and manufacturing method thereof - Google Patents

Description

  The present invention relates to a spiral membrane element that separates specific components present in various fluids (liquid or gas) and a method for manufacturing the same. More specifically, the present invention relates to an improvement in a method for forming a sealing structure near both side edges of a film.

  Conventionally, as a fluid separation element used for reverse osmosis filtration, ultrafiltration, etc., for example, a supply-side flow path material that guides a supply-side fluid (raw water) to the separation membrane surface, a separation membrane that separates the supply-side fluid, and a separation membrane Spiral membrane element that is wound around a perforated center tube with a permeate-side channel material that permeates the permeate-side fluid (permeate) separated from the supply-side fluid and leads to the center tube (collection tube) Is known (see, for example, Patent Document 1).

  As shown in FIGS. 5 (a) to 5 (b), such a spiral membrane element generally has a structure in which a supply-side channel material 2 is disposed between two folded separation membranes 1, and a permeation side. In order to stack the flow path material 3 and form a sealed portion that prevents mixing of the supply side fluid and the permeate side fluid, the adhesives 4 and 6 such as urethane resin are positioned on the periphery (three sides) of the separation membrane. A separation membrane unit U is produced by applying to the permeate-side channel material 3, and one or more of the units U are spirally wound around the central tube 5, and the adhesive 4 is left standing for a long time. , 6 is produced by curing. At that time, from the viewpoint of making the adhesive strength uniform and simplifying the coating process, as shown in FIG. It was applied.

  According to the above manufacturing method, as shown in FIG. 6, both ends of the separation membrane 1 facing each other through the permeate-side flow path member 3 are sealed by both-end sealing portions 11 having a constant width, and the permeate-side flow path The outer peripheral side end portion of the separation membrane 1 that faces the material 3 is sealed by the outer peripheral side sealing portion 12 along the axial direction (see, for example, Patent Document 2). This example is a case where there are a plurality of membrane leaves (sealed envelope-like membranes), but there are cases where there is a single membrane leaf (see, for example, Patent Document 1).

  On the other hand, the membrane element is required to reduce the fresh water generation cost, and the effective membrane area of the membrane element directly affects this, so that improvement is always desired. However, the standard for the vessel for loading the membrane element is uniform, and the volume of the membrane element itself has an upper limit. There are various methods for improving the effective film area in the upper limit volume, but the effect of reducing the resin width of the sealing portion is particularly high.

However, in the method of narrowing the resin width of the sealing portion, there are problems that the reliability of the sealing portion is impaired and the yield during production is reduced. For example, in the case of a membrane element using a UF membrane, the reliability of the sealing part is particularly problematic in the durability in the backwashing process. If the strength of the sealing portion is insufficient in the backwashing step of washing the material deposited on the supply side flow path with the permeated water, the portion is easily damaged. Also, in the case of membrane elements using RO membranes, depending on the position of the permeate tank, the water pressure at the head differential may occur in the backwash direction when the system is stopped. There is also a problem that is easily damaged.
On the other hand, if the resin width of the sealing portion is not set to a certain level or more, leakage may occur from the sealing portion due to misalignment of each member during production, or the resin width may become small and sufficient strength may not be ensured.

Japanese Patent Laid-Open No. 10-341 JP-A-2005-199141

  SUMMARY OF THE INVENTION An object of the present invention is to provide a spiral membrane element capable of maintaining the reliability of a sealing portion and the yield during production while improving the effective membrane area, and a method for manufacturing the same.

The above object can be achieved by the present invention as described below.
A spiral membrane element of the present invention includes a cylindrical wound body in which a separation membrane, a supply-side channel material, and a permeate-side channel material are wound in a spiral shape around a perforated central tube in a stacked state. In addition, in the spiral membrane element provided with a sealing portion for preventing the supply-side fluid and the permeation-side fluid from mixing, the separation membranes facing each other through the permeation-side flow path member have both ends on both sides in the axial direction. While having a sealing part, the both-ends sealing part is characterized in that the outer peripheral side is formed wider than the inner peripheral side.

  According to the researches of the present inventors, when the permeated water is made to flow backward in the backwashing process, a water hammer phenomenon occurs when the permeated water reaches the tip of the membrane leaf (end on the outer peripheral side). It has been found that a high pressure is locally applied to the outer peripheral side end portions of the both end sealing portions, and the sealing portions are easily damaged. In addition, even when the backwash process is not performed, the sealing part located on the outer peripheral side of the sealing part on both ends is easily damaged by deformation due to differential pressure during operation of the membrane element using the RO membrane or water pressure at the time of stopping. It has been found. For this reason, if the width | variety of the outer peripheral side edge part of both ends sealing part is maintained, even if it narrows the width | variety of an inner peripheral side, durability of a sealing part can be maintained.

  The spiral-type membrane element of the present invention is based on such an idea, and since the width on the inner peripheral side is narrower than the outer peripheral side of the both-end sealing portion, it is possible to improve the effective membrane area than before, At this time, the reliability of the sealing portion can be maintained. In addition, since the displacement of each member during production increases toward the outer peripheral side of the membrane element, the yield during production can be maintained by maintaining the width of the outer peripheral end of the sealing portion at both ends.

  In the above, it is preferable that the both end sealing portions are formed such that the width of the outermost peripheral side portion is 1.1 to 2.0 times the width of the innermost peripheral side portion. By setting it as this range, the improvement of an effective film area, and the maintenance of the reliability of a sealing part and the yield at the time of production can be made in balance.

  On the other hand, the manufacturing method of the spiral membrane element of the present invention is a winding step in which the separation membrane, the supply-side channel material, and the permeation-side channel material are spirally wound around the perforated central tube in a laminated state. And a method of manufacturing a spiral membrane element including a sealing step for forming a sealing portion for preventing mixing of the supply-side fluid and the permeation-side fluid, wherein the sealing step is performed via the permeation-side channel material. And a step of forming both end sealing portions that are wider on the outer peripheral side than on the inner peripheral side on both sides in the axial direction of the opposing separation membrane.

  According to the manufacturing method of the present invention, the width of the inner peripheral side can be made narrower than the outer peripheral side when forming both-end sealing portions, so that the effective membrane area can be improved as compared with the prior art. For the reason, the reliability of the sealing portion can be maintained. In addition, since the displacement of each member during production increases toward the outer peripheral side of the membrane element, the yield during production can be maintained by maintaining the width of the outer peripheral end of the sealing portion at both ends.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a process diagram showing an example of a spiral membrane element manufacturing method of the present invention. FIG. 2 is a partially broken perspective view showing an example of the spiral membrane element of the present invention.

  The spiral type membrane element and the manufacturing method thereof of the present invention differ from the conventional one only in the shape of the both-end sealing part, and other structures apply the above-described configuration of the conventional spiral type membrane element. Can do. First, the manufacturing method of the spiral membrane element of the present invention will be described.

  As shown in FIGS. 1A to 1B, the manufacturing method of the present invention includes a perforated central tube 5 in a laminated state in which a separation membrane 1, a supply-side channel material 2, and a permeate-side channel material 3 are laminated. It includes a winding step of winding around the periphery in a spiral shape and a sealing step of forming the sealing portions 11 and 12 for preventing mixing of the supply side fluid and the permeate side fluid. FIG. 1A is an assembled perspective view of a separation membrane unit, and FIG. 1B is a front view showing a state before the separation membrane units are stacked and wound.

  In the present embodiment, first, the separation membrane unit U is formed in which the supply-side flow path member 2 is disposed on the supply side of the separation membrane 1 folded with the supply side inward, and the permeation-side flow path member 3 is disposed on the permeation side. An example is shown. As the separation membrane unit U, for example, a width of 500 to 2000 mm, preferably a width of 1000 to 1600 mm can be used.

  The membrane 1 used in the present invention may be a porous membrane or a non-porous membrane having a pressure loss of a certain level or more for permeation. Specifically, a microfiltration membrane, an ultrafiltration membrane, a nanofiltration membrane, Examples include reverse osmosis membranes, ion exchange membranes, gas separation membranes, and dialysis membranes.

  As the material of the membrane 1, a polymer membrane such as polyolefin such as polypropylene or polyethylene, polysulfone, polyethersulfone, polystyrene, polyacrylonitrile, cellulose acetate, polyamide, polyimide, fluororesin, or the like can be used. The membrane 1 may have a reinforcing layer such as a porous support layer. In that case, the permeate-side flow path member 3 is generally disposed on the reinforcing layer side.

  As the permeation side channel material 3, any conventionally known permeation side channel material can be used as the spiral membrane element, and any of net, mesh, wire woven fabric, fiber woven fabric, non-woven fabric, etc. may be used. The material may be any of natural polymers, rubber, metals, etc., in addition to resins such as polypropylene, polyethylene, polyethylene terephthalate (PET), polyamide, epoxy, and urethane. However, when elution from the channel material becomes a problem during the separation operation or the like, it is preferable to select the material in consideration thereof.

  The thickness of the permeate side channel material 3 is preferably 0.2 to 1 mm, and the porosity in the thickness direction of the permeate side channel material 3 is preferably 10% or more and 60% or less. Moreover, when the permeation | transmission side channel material 3 is net shape, it is preferable that the pitch is 0.3 mm or more and 5 mm or less.

  As the supply-side channel material 2, any conventionally known supply-side channel material can be used as the spiral membrane element, and any of a net, a mesh, a wire woven fabric, a fiber woven fabric, a nonwoven fabric, a grooved sheet, a corrugated sheet, and the like may be used. . Further, the material may be any of natural polymers, rubber, metals, etc., in addition to resins such as polypropylene, polyethylene, polyethylene terephthalate (PET), and polyamide. However, when elution from the channel material becomes a problem during the separation operation or the like, it is preferable to select the material in consideration thereof.

  The thickness of the supply-side channel material 2 is preferably from 0.3 mm to 2 mm, and the porosity in the thickness direction of the supply-side channel material 2 is preferably from 10% to 70%. Moreover, when the supply side flow-path material 2 is net shape, it is preferable that the pitch is 0.5 mm or more and 10 mm or less.

  The separation membrane 1 can be folded using a hand or a jig, or using an apparatus that automates this. At that time, in order to stabilize the crease, maintain the shape, increase the strength, and the like, it is preferable to perform heating and pressurization when the film 1 is folded or after folding. Specifically, a method of sandwiching the folded portion using a pair of heating plates, a method of passing between a pair of heated rolls, a method of pushing the folded portion into a heating body in which a gap capable of holding the folded portion is formed, etc. It is done. This heating and pressurization may be performed at the time of folding or after folding, or at the time of folding and after folding, but it is preferable to hold the heating and pressing state for a certain time after folding.

  In the manufacturing method of the present invention, as the sealing step, both end sealing portions 11 whose outer peripheral side is wider than the inner peripheral side are formed on both sides in the axial direction of the separation membrane 1 facing each other through the permeation-side flow path member 3. For example, as shown in FIG. 1A, after forming the separation membrane unit U, after applying the adhesive 4 so that the width on the outer peripheral side is wider than the inner peripheral side, as shown in FIG. It can be carried out by bonding and curing. As the adhesives 4 and 6, any conventionally known adhesives such as urethane adhesives, epoxy adhesives and hot melt adhesives can be used. Thereby, the outer peripheral side of the both ends sealing part 11 is formed more widely than the inner peripheral side.

  In the present invention, the width W2 of the outermost peripheral side portion is preferably 1.1 to 2.0 times the width W1 of the innermost peripheral side portion, and is preferably 1.3 to 1.5 times larger. More preferably, it is formed. When the width W2 of the outermost peripheral side portion is less than 1.1 times, the change in the width is small, and the effect of improving the effective film area tends to be small. On the contrary, if the width W2 of the outermost peripheral side exceeds 2.0 times, the width W1 of the innermost peripheral side becomes too small, and it tends to be difficult to maintain the reliability of the sealing portion.

  Specifically, the width W1 of the innermost peripheral side portion of the both end sealing portion 11 is desirably 5 to 30 mm, and more desirably 10 to 20 mm. Further, the width W2 of the outermost peripheral side portion is desirably 10 to 40 mm, and more desirably 20 to 30 mm.

  As a method of applying the adhesive 4 so that the width on the outer peripheral side is wider than the inner peripheral side, when the discharge nozzle of the resin that is the adhesive 4 is moved from the inner peripheral side to the outer peripheral side, as shown in FIG. As shown, after the discharge nozzle is moved in the direction of the arrow A inclined from the end side, the adhesive 4 having a certain width is applied obliquely, and then cut along the line C after winding and curing. It is done. In that case, the inclination angle with respect to the end side is preferably 0.04 to 0.38 ° from the viewpoint of appropriately changing the width of the both end sealing portion 11.

  When the discharge nozzle is moved from the inner peripheral side to the outer peripheral side, the resin discharge amount is gradually increased while moving the discharge nozzle in the direction of arrow B parallel to the end side as shown in FIG. A method of cutting along the line C after winding / curing after applying the adhesive 4 having a wider width toward the outer peripheral side can be mentioned. At that time, the change in the discharge amount is performed so that the discharge amount at the end changes by 10 to 200% with respect to the initial discharge amount from the viewpoint of appropriately changing the width of the both end sealing portion 11. Is preferred.

  Further, as shown in FIG. 3B, when the discharge nozzle is similarly moved in the direction of arrow B, the adhesive 4 having a wider width toward the outer peripheral side can be applied by gradually decreasing the movement speed of the discharge nozzle. can do. At this time, the nozzle moving speed is changed so that the moving speed at the end changes by 10 to 200% with respect to the initial moving speed from the viewpoint of appropriately changing the width of the sealing portion 11 at both ends. It is preferable to do this.

  Next, as shown in FIG. 1B, the separation membrane unit U is stacked for the set leaf, and is wound around the perforated center tube 5 in a spiral shape. The number of set leaves is, for example, 15 to 50 leaves for an 8-inch size. In the present embodiment, one end of the permeate-side flow path member 3 having a longer length than the other is fixed to the central tube 5, and the separation membrane unit U is arranged at an interval that matches the circumferential length of the central tube 5. .

  As the center tube 5, any conventionally known tube can be used, and examples thereof include metals, fiber reinforced plastics, plastics, and ceramics. Any known hole shape, size, position, number, etc. may be employed depending on the type of membrane.

  The outer diameter and length of the center tube 5 are appropriately determined according to the size of the spiral membrane element. For example, the outer diameter is 10 to 100 mm and the length is 500 to 2000 mm, preferably the outer diameter is 12 to 38 mm and the length is 900 to 1200 mm. In this example, the central tube 5 is a permeate-side flow channel (for example, a water collecting tube).

  As a method of fixing the laminate (membrane leaf) to the central tube 5, in addition to thermal fusion or ultrasonic fusion, adhesion by an adhesive, adhesion by adhesive tape, double-sided tape, thermal fusion material, mechanical adhesion Any may be sufficient. The fixing sites can be corrected by the arrangement of the film or the like, not necessarily at regular intervals, but are preferably at substantially regular intervals. In the case of substantially equal intervals, it is preferable to set the interval obtained by dividing the outer peripheral length of the central tube 5 by the number of membrane leaves to be fixed.

  For winding the laminated body, for example, by setting the central tube 5 on a chuck of a winding device and rotating the chuck at a constant speed, the entire membrane leaf can be wound up. At this time, the end face can be satisfactorily aligned by pressing the roll against the cylindrical wound body R with a constant pressure.

  Next, in order to solidify and seal the both-end sealing portion 11 and the outer peripheral side sealing portion 12, the rolled up cylindrical wound body R is heated and dried while maintaining the shape. For example, when using a urethane-based adhesive or the like as the adhesives 4 and 6, the wound cylindrical wound body R is allowed to stand in a dryer at 30 to 60 ° C. for 1 to 2 hours to cure urethane resin or the like. And then allowed to cool to room temperature and solidify completely. In that case, you may seal the outer peripheral side sealing part 12 around the center pipe 5 simultaneously.

  Thereafter, both ends of the cylindrical wound body R are trimmed as necessary in order to adjust the length in the axial direction.

  The spiral membrane element of the present invention can be preferably manufactured by the manufacturing method of the present invention as described above. That is, the spiral membrane element of the present invention includes a perforated central tube 5 in which the separation membrane 1, the supply-side channel member 2, and the permeate-side channel member 3 are laminated as shown in FIGS. Is provided with a cylindrical wound body R wound in a spiral shape and a sealing portion for preventing mixing of the supply side fluid and the permeation side fluid. In the present embodiment, an example in which the both end sealing part 11 and the outer peripheral side sealing part 12 are included is shown as the sealing part.

  As shown in FIG. 2, both ends of the separation membrane 1 facing each other through the permeate-side flow path member 3 are sealed by both-end sealing portions 11 and between a plurality of both-end sealing portions 11 arranged in a spiral shape. The supply-side flow path material 2 is interposed between them. Moreover, the outer peripheral side edge part of the separation membrane 1 which opposes through the permeation | transmission side flow path material 3 is sealed by the outer peripheral side sealing part 12 along the axial direction.

  In the spiral membrane element of the present invention, the separation membrane 1 that faces the permeation-side flow path member 3 has both end sealing portions 11 on both sides in the axial direction, and the both end sealing portions 11 are formed from the inner peripheral side. The outer peripheral side is widely formed.

  The spiral membrane element of the present invention is usually constrained by an exterior material and does not expand in diameter, but the exterior material is formed by winding one or more sheets around the surface of the cylindrical wound body R. Can do. As the exterior material, polyester, polypropylene, polyethylene, polyvinyl chloride, glass fiber cloth, or the like can be used.

  The spiral membrane element of the present invention can be further provided with a perforated end member for preventing deformation (telescope or the like), a sealing material, a reinforcing material, and the like as necessary.

[Other Embodiments]
(1) In the above-described embodiment, the example in which the width of the both end sealing portion is changed at a constant rate from the innermost peripheral side portion to the outermost peripheral side portion of the both end sealing portion is shown. For example, as shown in FIGS. 4A to 4C, it is only necessary to have an inner peripheral side portion that is narrower than the outer peripheral side portion. Both sides of the changing portion may be a straight line or a curved line. In addition, the both ends sealing part 11 of such a shape can be formed by controlling the moving direction of a discharge nozzle two-dimensionally.

  In the example shown in FIG. 4A, the length L1 portion of the both-end sealing portion 11 is formed with the same width W2 as the outermost peripheral side portion, and the length L2 portion of the both-end sealing portion 11 is the innermost portion. This is an example in which a portion having the same width W1 as the peripheral side portion and a width changing portion is provided in the middle. Thus, by forming 50% or more, particularly 65% or more, of the entire length of the both-end sealing part 11 with the same width W1 as the innermost peripheral part, and forming a wider outer peripheral side than this, the reliability of the sealing part is increased. The effective membrane area can be improved more effectively while maintaining the properties.

  The example shown in FIG. 4B is an example in which only the length L1 portion of the both-end sealing portion 11 is formed with a constant width W2. Further, in the example shown in FIG. 4C, the substantially full length of the both end sealing portion 11 is formed with the same width W1 as the innermost peripheral side portion, and when changing the outer peripheral side width, one side becomes a curve. It is an example.

  (2) In the above-described embodiment, an example in which the both-end sealing portion is formed by applying and curing an adhesive is shown. However, both ends using an adhesive sheet that softens by heating and solidifies by cooling or reaction curing. A sealing portion may be formed. In that case, by cutting the adhesive sheet or the like into a predetermined shape in advance, it is possible to easily form both-end sealing portions whose outer peripheral side is wider than the inner peripheral side.

  (3) In the above-described embodiment, an example in which the adhesive is applied to the permeation-side flow path material has been described. However, it is also possible to apply the adhesive to the separation membrane.

  (4) In the above-described embodiment, when the separation membrane unit is manufactured, the separation membrane is folded in half and the supply-side flow path material is sandwiched. However, the separation membrane unit is folded back alternately using a continuous separation membrane. It is also possible to sandwich the supply-side channel material and the permeation-side channel material.

  (5) In the above-described embodiment, as shown in FIG. 1, the permeation-side channel material 3 is overlapped on the separation membrane 1 folded in half so as to sandwich the supply-side channel material 2, and the adhesive 4 In the present invention, it is also possible to apply the adhesives 4 and 6 on the separation membrane 1 that is folded in two on the permeate-side channel material 3.

  (6) In the above-described embodiment, as shown in FIG. 1, an example in which a spiral membrane element including a plurality of membrane leaves is manufactured using a plurality of separation membrane units U has been described. A spiral membrane element having one membrane leaf may be manufactured using a set of separation membrane units U.

  Examples and the like specifically showing the configuration and effects of the present invention will be described below.

Example 1
In accordance with the steps shown in FIGS. 1 (a) to 1 (b), spiral membrane elements were produced under the following materials and conditions, and evaluated.

  While feeding out Nitto Denko's RO membrane (CPA3), cut it to a predetermined length (1500 mm) and paste the tape across the width direction at equal intervals at the folds on the membrane side on the supply side I attached. Thereafter, the membrane was folded in half while sandwiching the supply side channel material made of polypropylene, and the transmission side channel material made of PET was thermally fused.

  Furthermore, while discharging urethane resin at a constant flow rate from above, the resin discharge nozzle position was moved from the central tube side toward the end of the membrane leaf, changing the moving speed so that the sealing width gradually increased (Fig. 3 (b)). At that time, the moving speed of the nozzle was 400 mm / sec at the initial speed, and the speed was decreased by 30% / sec. As for the membrane leaf to which the urethane resin was applied, a laminate was prepared by repeating resin application and lamination for the set number of membrane leaves (number of leaves: 29).

  The central tube was set on the winding chuck of the assembly assembled as described above, and the entire membrane leaf was wound up by rotating the chuck at a constant speed. At this time, the roll was applied to the element with a constant pressure to align the end faces. At this time, there were no wrinkles, folds or deviations in the membrane leaf.

  The wound element was allowed to stand in a dryer at 60 ° C. for 1 hour to promote curing of the urethane resin used for sealing, and then returned to room temperature to be completely solidified. The element having the solidified sealing portion was trimmed at both ends thereof to have a width of 15 mm at the innermost peripheral side portion of the sealing portion at both ends and a width of 20 mm at the outermost peripheral side portion. In this manner, an 8-inch spiral membrane element was manufactured. As for the element that had been solidified, air permeation was performed on the permeate side in the leaf with a pressure of 0.05 MPa from the central tube in water, and as a result of confirming the sealing property, generation of bubbles from the supply side was not observed. Further, as a result of measuring the membrane characteristics, predetermined membrane performance (salt rejection, permeation flow rate) was satisfied.

Example 2
In Example 1, an 8-inch spiral membrane element was manufactured in the same manner except that the nozzle moving speed was constant (400 mm / sec) and the nozzle moving direction was inclined. The characteristics were measured. As a result, the sealing properties and the film properties were as good as in Example 1. In addition, the moving direction of the nozzle is inclined by 0.38 ° with respect to the end side (see FIG. 3A), and both end sealing portions after trimming have an innermost peripheral side width of 15 mm and an outermost peripheral side portion. The width was 30 mm.

Example 3
In Example 1, an 8-inch spiral membrane element was manufactured in the same manner except that the nozzle moving speed was constant (400 mm / second) and the discharge amount from the nozzle was changed. Membrane characteristics were measured. As a result, the sealing properties and the film properties were as good as in Example 1. Note that the discharge amount from the nozzle is set to 600 g / sec as the initial amount, and the discharge amount is increased by 105 g / sec (see FIG. 3B). The width was 15 mm and the width of the outermost peripheral side portion was 25 mm.

Process drawing which shows an example of the manufacturing method of the spiral type membrane element of this invention The partially broken perspective view which shows an example of the spiral type membrane element of this invention Process drawing which shows the example of the coating method of resin in this invention The top view which shows the other example of the principal part of the spiral type membrane element of this invention Process drawing showing an example of a conventional method for manufacturing a spiral membrane element Partially broken perspective view showing an example of a conventional spiral membrane element

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Separation membrane 2 Supply side flow path material 3 Permeation side flow path material 4 Adhesive 5 Center pipe 6 Adhesive 11 Both ends sealing part 12 Outer peripheral side sealing part R Cylindrical winding body U Separation membrane unit W1 Both ends sealing part Width of the innermost peripheral side of W2 Width of the outermost peripheral side of the sealing portion at both ends

Claims (4)

A separation membrane, a supply-side flow path material, and a permeate-side flow path material are provided with a cylindrical wound body spirally wound around a perforated central tube in a laminated state, and a supply-side fluid and a permeation-side fluid In the spiral membrane element provided with a sealing portion for preventing the mixing of
The separation membrane facing through the permeate-side channel material has both end sealing portions on both sides in the axial direction, and the both end sealing portions are formed wider on the outer peripheral side than on the inner peripheral side. Spiral membrane element.   2. The spiral membrane element according to claim 1, wherein the both-end sealing portion is formed with a width of the outermost peripheral side portion 1.1 to 2.0 times larger than a width of the innermost peripheral side portion. To prevent the mixing of the supply side fluid and the permeate side fluid, and the winding step of spirally winding the separation membrane, the supply side flow channel material and the permeate side flow channel material around the perforated central tube In the manufacturing method of the spiral type membrane element including the sealing step of forming the sealing portion of
The sealing step includes a step of forming both-end sealing portions whose outer peripheral side is wider than the inner peripheral side on both sides in the axial direction of the separation membrane facing each other through the permeate-side channel material. Manufacturing method of membrane element.   4. The method for manufacturing a spiral membrane element according to claim 3, wherein the sealing portion on both ends is formed such that the width of the outermost peripheral side is 1.1 to 2.0 times the width of the innermost peripheral side. .

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