JP2005305422A - Spiral type separation membrane element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spiral type separation membrane element which is capable of reducing the pressure loss of a supplying side passage and moreover less likely to cause the problem of inhibiting and blocking the flow of the supplying side passage. <P>SOLUTION: In this spiral type separation membrane element in which at least one of a separation membrane, a supplying side passage material and a penetrating side passage material is wound around a porous hollow central tube, the supplying side passage material is a net obtained by a heat-fusion method molding. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spiral separation membrane element that separates components dissolved in a liquid, and more specifically, pressure loss on the supply side can be made smaller than before and concentration polarization on the membrane surface The present invention relates to a spiral-type separation membrane element having a built-in supply-side flow path material having a structure having a stirring effect necessary for suppressing the above.

  Conventionally, as a structure of a spiral type separation membrane element, one or more of a separation membrane, a supply side channel material and a permeate side channel material is wound around a perforated hollow central tube. It has been. In addition, there is a report that a rhombus net-like channel material is used for the supply-side channel material in the case of a reverse osmosis membrane, thereby reducing pressure loss (see, for example, Patent Documents 1 to 3). ). Specifically, a configuration example as shown in FIG. 11 can be given.

  On the other hand, for the purpose of reducing the pressure loss of the supply-side flow path, a ladder-shaped net-shaped flow path material composed of warp yarns parallel to the flow direction of the supply liquid and wefts connecting the warp yarns is employed (for example, Patent Document 4). reference). The present invention does not focus on the relationship between the thickness of the warp and the weft and the relationship between the warp and the weft, and nothing is mentioned about the thickness of the warp and the weft.

  However, the resistance due to the flow of the supply water in the supply-side flow channel is largely governed by the supply-side flow path material, and the resistance increases due to the nature of the supply water and the components contained in the supply water, depending on the quality of the supply water. It leads to.

  In the conventional net, in the case of the ladder type, the weft and the warp are usually the same diameter, the weft impedes the flow of the supply liquid, and the floating component causes the flow path to be blocked. Also, in the case of a rhombus, there is no distinction between vertical and horizontal directions, but the same is true because two intersecting yarns cross the flow path. In other words, in addition to the function of reducing the pressure loss on the supply side as much as possible, the supply-side flow path material is required to have a function of suppressing the concentration polarization by promoting surface renewal of the membrane surface. There is a problem in that the components floating in the supply liquid are caught by the weft and the flow resistance is increased or blocked. Further, there is a problem that components floating in the supply liquid on the membrane surface are caught by the supply flow path material weft, and they are deposited on the film surface to reduce the effective membrane area. In addition to this, there is a problem of reducing pressure loss in the supply channel material in order to reduce the operating cost of the separation membrane element.

On the other hand, conventional nets are often formed by a shearing method so that the weft and the warp can be reliably fused. This shearing method is used when weft yarns and warp yarns are extruded and fused to each other at the intersection while rotating a number of nozzle holes arranged on two circumferences inside and outside the die of the extruder in opposite directions. This is a method using a die in which nozzle holes are arranged so that both nozzle holes overlap to form one nozzle. According to the shearing method, the extrusion amount of the resin increased at the intersection of the weft and the warp, and a web-like deformation occurred at this portion. As a result of investigations by the present inventors, it has been found that this scuff-like deformation causes an increase in pressure loss in the supply-side flow path.
JP 11-235520 A JP 2000-000437 A Japanese Patent Laid-Open No. 2000-042378 JP 05-168869 A

  Accordingly, an object of the present invention is to provide a spiral separation membrane element that can reduce the pressure loss of the supply-side flow path and that is less likely to cause problems of obstruction and blockage of the flow of the supply-side flow path.

  As a result of intensive studies, the present inventors have found that the object can be achieved by the spiral separation membrane element described below, and have completed the present invention.

  The present invention relates to a spiral separation membrane element in which one or more of a separation membrane, a supply-side channel material, and a permeation-side channel material are wound around a perforated hollow central tube. The road material is a net obtained by fusion molding. Here, the net obtained by fusion method molding has a structure in which the constituent yarns of the net are fused to each other at the intersection, and the fused portion does not protrude from the constituent yarns in a planar shape (projected figure). It is.

  The present inventor is able to reduce the pressure loss of the supply-side flow path by reducing the water-like deformation at the intersection in the molding of the net compared to the shearing-molded product in the molding of the net. The present invention has been found to be effective for preventing obstruction and blockage of the flow path, and can provide an excellent spiral separation membrane element.

  In addition, the fusion-molded product has a smoother surface than the shear-method molded product, and damage to the membrane due to contact with the membrane surface during element assembly work and pressing against the membrane surface by winding is alleviated. And is very effective for forming a spiral separation membrane element.

  In the above, it is preferable that the supply side flow path member has a weft that intersects the supply liquid flow direction thinner than a warp arranged along the supply liquid flow direction. In the net molded product, the cross-sectional area of the supply liquid flow path can be increased by thinning the weft that intersects the supply liquid flow direction, which is effective for blocking or blocking the flow of the supply-side flow path. Yes, the pressure loss of the flow path can be reduced.

  The supply-side channel material is a net-shaped channel material, and is preferably formed in a structure in which the warps arranged along the supply liquid flow direction meander. In order to prevent obstruction or blockage of the flow in the flow path, it is known that it is effective to make the liquid flow in the flow path turbulent (turbulent flow effect). In the present invention, it has been devised that a turbulent flow effect larger than that of a flow path material such as a conventional ladder type or rhombus can be obtained by making the warp yarn of the flow path material meander. It is possible to provide an excellent spiral-type separation membrane element with little pressure loss in the passage.

  The supply-side flow path material has a two-layer structure including a first layer composed of a first thread and a second layer composed of a second thread, and the first thread and the second thread Each of which repeatedly includes a parallel portion disposed substantially parallel to the supply liquid flow direction and an inclined portion disposed obliquely with respect to the supply liquid flow direction, and the parallel portion of the first yarn and the second It is preferable that the parallel part of the yarn is fused to form a hexagonal unit plane shape.

  According to such a supply-side flow path material, the first yarn and the second yarn are overlapped and fused at the parallel portion, so that this portion is unlikely to become the resistance of the supply liquid, and the hexagonal unit plane Because of the shape, the number of intersections per unit flow length (in this case, the number of parallel portions) can be reduced, and the pressure loss in the supply-side flow path can be further reduced.

  Alternatively, the supply-side channel material includes warp yarns arranged substantially parallel to the supply liquid flow direction, inclined yarns arranged obliquely with respect to the supply liquid flow direction, and the inclined yarns arranged with respect to the supply liquid flow direction. Preferably has a three-layer structure composed of reversely inclined yarns arranged in opposite diagonal directions.

  According to such a supply-side channel material, the layer composed of warp yarns is less likely to become resistance of the supply liquid, and the slanted and reverse inclined threads are thinner than the two-layer structure in the supply liquid flow direction. Therefore, this portion is unlikely to become the resistance of the supply liquid, and the pressure loss of the supply side flow path can be further reduced.

  As described above, the present invention can reduce the pressure loss of the supply side flow path by using the fusion method in the formation of the net used for the spiral separation membrane element, and can further reduce the flow of the supply side flow path. There is an advantage that inhibition and blockage can be prevented. At the same time, there is an advantage that workability such as element assembly is high.

  Also, make the weft that intersects the flow direction of the feed liquid thinner, or make the thread in one direction thinner in the rhombus net-like channel material, and warp in the ladder-like net channel material By forming a meandering structure, it is possible to effectively reduce the pressure loss of the supply side flow path, inhibit flow and prevent clogging.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1A and 1B are diagrams showing an example of a supply-side channel material of a spiral separation membrane element of the present invention, where FIG. 1A is a front view and FIG. 1B is a side view.

  The spiral separation membrane element of the present invention has a structure in which one or more of a separation membrane, a supply-side channel material and a permeation-side channel material are wound around a perforated hollow central tube. The details of the membrane element are also described in detail in the above-mentioned Patent Documents 1 to 4, and conventionally known separation membranes, permeation side flow channel materials, hollow center tubes, etc., except for the supply side flow channel materials Can be employed. For example, when a plurality of supply side flow path materials and permeation side flow path materials are used, a plurality of membrane leaves are wound around a hollow central tube.

  For example, as shown in FIG. 1, the supply-side channel material used in the present invention forms a ladder-shaped net-like channel material having warp yarns 1 and weft yarns 2 in the flow direction of the supply water. The present invention is characterized in that the supply-side channel material is a net obtained by fusion molding.

  When the net is formed by the fusion method, generally, the weft and warp yarns are extruded while rotating a number of nozzle holes arranged on the inner and outer circumferences of the extruder die in the opposite direction, and then the intersection. Then, they are fused with each other, immersed in a cooling bath, and then taken out. When performing the above extrusion, arrange the nozzle holes so that the nozzle holes do not overlap at the intersection of the weft and the warp (this is different from the shearing method), and the extruded weft and warp are moderately It is fused at the timing when proper fusion occurs.

  Therefore, compared to the shearing method, the shape of the weft and the warp is easily maintained at the intersection, and the amount of resin extruded at the intersection is not increased. The pressure loss of the supply side flow path can be reduced.

  In particular, when a net as shown in FIG. 1 (A) is formed by the fusion method, the nozzle diameters of the weft and the warp are changed, and the weft nozzle hole is rotated only without rotating the warp nozzle hole. The method is effective.

  As a component of the channel material, in addition to a material selected in consideration of corrosion resistance, heat resistance, mechanical strength, etc. (described later), the channel cross-sectional area is structurally large, for example, FIG. The diameter of the warp 1, the diameter of the weft 2 and the thickness 3 determined thereby, the warp interval 4, the weft interval 5, and the intersection angle 6 in the configuration example shown in FIG. In other words, for example, in terms of mechanical strength, the diameter of the warp 1 and the diameter of the weft 2 are preferably larger, but it is not preferable because the cross-sectional area of the flow path is reduced and the pressure loss is increased. Further, if the intersection angle is reduced, the joining portion between the warp 1 and the weft 2 is increased, which is preferable in terms of strength. I can't say that.

  According to the present invention, by selecting these elements, an optimum flow path is formed for reducing the pressure loss, preventing flow obstruction, and preventing the blockage of the flow path. We have studied the influence of the above, and found that the fusion method is optimal as a joining method capable of forming a smooth flow without any water-like deformation.

  In other words, a net formed by a conventional method, for example, a shearing method, causes a web-like deformation at the intersection, but the fusion-molded product according to the present invention has much less deformation than the shear-method molded product. In addition, the fusion-molded product has a smoother surface than other molded products such as a shear-molded product, and damage to the membrane due to contact with the membrane surface during element assembly work or pressing against the membrane surface due to winding There are advantages such as mitigation. These advantages are very useful in forming a flow path material, and provide an excellent spiral-type separation membrane element that is unprecedented even if it has the same structure by the fusion-molded article of the present invention. be able to.

  In particular, in the case of a ladder-type channel material, the length of the weft 2 in contact with the flow is often increased, and this advantage of the fusion-molded product can be utilized to the maximum. In addition to the superiority, it is possible to take advantage of the synergistic effect with these advantages of the fusion-molded product.

  Here, any material can be used as the raw water side channel material of the supply side channel to be used, but it is selected in consideration of the corrosion resistance, heat resistance, mechanical strength and the like as described above. The Examples thereof include polypropylene and polyethylene.

  In addition, as shown in FIG. 1 (B), to reduce the pressure loss due to the flow of the feed water, the cross-sectional area of the flow path of the feed liquid can be reduced by thinning the weft that intersects the feed liquid flow direction. It is effective for obstructing or blocking the flow of the supply side flow path, and the pressure loss of the flow path can be reduced.

  That is, in the conventional ladder-type channel material, the weft and the warp are formed with substantially the same diameter, and the actual channel cross-sectional area of the supply-side channel cross-sectional area is less than ½. Absent. The same applies to the rhombus channel material. In the flow channel material of the present invention, the cross-sectional area of the flow channel is increased by reducing the ratio of the weft yarn diameter to the warp yarn in the ladder shape, and the yarn diameter ratio in either direction in the rhombus shape, and the pressure loss is the conventional one. It becomes possible to make it smaller than that. Specifically, the inventors have obtained knowledge that the warp: weft diameter ratio is suitably 4: 1 to 2: 1. Furthermore, by applying such a configuration to the fusion-bonded molded article of the present invention, there is very little scratch-like deformation at the intersections compared to conventional shear molded articles, and the effect of reducing the diameter ratio of the weft to the warp is reduced. This can be ensured more reliably and is a factor that further reduces resistance.

  Furthermore, in the present invention, in addition to the expansion of the cross-sectional area of the flow path, the entire surface of the weft 2 is in contact with the flow, so that the surface slipperiness of the above fusion-molded product and the contact with the membrane surface during the element assembly operation The function of reducing the damage to the membrane due to the pressure on the membrane surface by winding or winding will produce a synergistic effect that is further increased by the reduction of the diameter of the weft yarn 2, and the pressure loss of the supply side flow path is further reduced. A small number of excellent spiral separation membrane elements can be provided.

  As another embodiment of the spiral-type separation membrane element of the present invention, a configuration in which a ladder-type net-like channel material is modified is shown in FIG. 2 (second configuration example). By moving the warp yarn 1 in the first configuration example in the flow direction of the feed water so that the intersection angle 6 becomes large, the warp interval 4 is increased while the joint portion between the warp yarn 1 and the weft yarn 2 is left as it is. . With such a configuration, an excellent net that can lengthen the joint portion between the warp yarn 1 and the weft yarn 2 to ensure a sufficient strength surface of the net-like channel material and at the same time increase the channel cross-sectional area. Can be formed.

  Moreover, it can be said that the pressure loss can be adjusted by adjusting the intersection angle 6 in the flow path, and that it has an excellent function that has not been achieved in the past. That is, when the intersection angle 6 is increased as described above, the warp interval 4 is increased and the flow path sectional area is increased, and when the intersection angle 6 is decreased, the warp interval 4 is decreased and the flow path sectional area is decreased. However, the weft interval 5 becomes smaller when the intersection angle 6 is increased, and as a result, there is an effect of increasing the pressure loss, so that the effect of reducing the pressure loss due to the increase of the cross-sectional area of the flow path is limited. Accordingly, by appropriately selecting the warp interval 4, the weft interval 5, and the intersection angle 6, a flow path material having a desired pressure loss can be created.

  FIG. 3 shows a third configuration example of the present invention. It is a ladder-type net-like channel material, and is characterized by being formed in a structure in which warp yarns meander. In order to prevent obstruction and blockage of the flow in the flow path, and to reduce pressure loss, it is effective to make the flow of liquid in the flow path turbulent and meander the warp yarns of the flow path material. By adopting a structure, it is possible to obtain a turbulent flow effect larger than that of a conventional ladder type or rhombus type channel material. Therefore, it is possible to provide an excellent spiral separation membrane element with little pressure loss in the supply side flow path. In particular, when the diameters of the warp and the weft are different, the turbulence of the flow is increased, a further turbulent flow effect can be obtained, and the pressure loss of the supply side flow path can be reduced.

  That is, in the conventional ladder type, the turbulent effect is obtained by the weft, and in the rhombus shape, the turbulent effect is obtained by the intersecting two-direction yarns although there is no distinction between the vertical and horizontal directions. In the flow channel material of the present invention, a high turbulence effect was obtained more easily than a straight line in parallel with the water flow by making the warp thread meander. In view of the configuration of the flow path material, the present invention adds a new element such as the meandering angle of warp 7 to the constituent elements such as the diameter of the warp 1 in the first configuration example as shown in FIG. Thus, the optimum flow path conditions are set for reducing the pressure loss of the flow path, inhibiting the flow and preventing the blockage. Further, similarly to the second configuration example, by appropriately selecting the warp interval 4, the weft interval 5, the intersection angle 6, and the warp meander angle 7, a flow path material having a desired pressure loss can be created.

  Specifically, if the thickness of the raw water side flow path material used in the supply side flow path is considered to be 26 mil, 28 mil, 34 mil, the pressure loss in the conventional product is reduced to 1/2. In order to obtain this, it is preferable to set the components of the supply-side flow path within the range shown in Table 1.

以上のように本発明の３つの構成例について述べたが、これらは、流路材の形成からみると、特定の流路材を成形した後、第１構成例→第２構成例→第３構成例の順に、幅方向（供給水流れ方向に対し垂直方向）への伸縮の度合いを変更することによって得られるものである。従って、使用条件にあった流路材を、非常に容易に作成することができるという優れた特徴を有している。

As described above, the three configuration examples of the present invention have been described. From the viewpoint of the formation of the flow path material, after forming a specific flow path material, the first configuration example → the second configuration example → the third This is obtained by changing the degree of expansion and contraction in the width direction (perpendicular to the feed water flow direction) in the order of the configuration example. Therefore, it has the outstanding characteristic that the flow path material suitable for use conditions can be produced very easily.

  4 to 5 show a fourth configuration example of the present invention, in which (A) is a front view, (B) is a side view, and (C) is a bottom view. In this example, as shown in FIGS. 4 to 5, the supply-side flow path material is composed of a first layer L <b> 1 composed of the first yarn 11 and a second layer L <b> 2 composed of the second yarn 12. It has a layer structure. At this time, each of the first yarn 11 and the second yarn 12 has parallel portions 11a and 12a arranged substantially parallel to the supply liquid flow direction and inclined portions 11b and 12b arranged obliquely with respect to the supply liquid flow direction. And repeatedly. Furthermore, the parallel portion 11a of the first yarn 11 and the parallel portion 12a of the second yarn 12 are fused to form a hexagonal unit plane shape.

  In the fourth configuration example, what is shown in FIG. 4 is an example in which the inclined portions 11b and 12b of the first yarn 11 and the second yarn 12 are inclined in the same direction, as shown in FIG. Is an example in which the inclined portions 11b and 12b of the first yarn 11 and the second yarn 12 are alternately inclined in opposite directions. In the case shown in FIG. 5, since each of the first yarn 11 and the second yarn 12 is arranged along the supply liquid flow direction while meandering, the pressure loss of the supply-side flow path can be further reduced.

  When the net shown in FIG. 4 is formed by the fusing method, both the nozzles of the first thread 11 and the nozzle holes of the second thread 12 are rotated in the opposite directions, and only when the parallel portions 11a and 12a are extruded. What is necessary is just to perform the control which stops rotation of a nozzle hole, and to rotate both nozzle holes intermittently. The extruded parallel portions 11a and 12a are fused to each other.

  Further, when the net shown in FIG. 5 is molded by the fusion method, both nozzle holes are rotated in the opposite directions when the inclined portions 11b and 12b are extruded, and both nozzle holes are rotated when the parallel portions 11a and 12a are extruded. When the next inclined portions 11b and 12b are pushed out, the respective nozzle holes are rotated in the reverse direction as when the previous inclined portions 11b and 12b are pushed out, and then the rotation of both nozzle holes is stopped and these are repeated. It is sufficient to perform such control.

  In this configuration example, the thickness of the intersection of the first yarn 11 and the second yarn 12 is preferably 0.5 to 1.0 mm. Moreover, as for the thread diameter of the 1st thread | yarn 11 and the 2nd thread | yarn 12, 0.15-0.5 mm is preferable. Further, the apex angle α in the hexagonal unit plane shape is preferably 60 to 120 °, and the hypotenuse lengths A and B (that is, the lengths of the inclined portions 11b and 12b) are preferably 2 to 5 mm, and the parallel portions 11a, The length of 12a is preferably 1 to 5 mm.

  FIG. 6 shows a fifth configuration example of the present invention, in which (A) is a front view, (B) is a side view, and (C) is a bottom view. In this example, as shown in FIG. 6, the supply-side flow path material has a three-layer structure including a first layer L1, a second layer L2, and a third layer L3. Each layer is composed of warp yarns 16 arranged substantially parallel to the supply liquid flow direction, inclined yarns 15 arranged obliquely with respect to the supply liquid flow direction, and diagonally opposite to the inclined yarns 15 with respect to the supply liquid flow direction. It is comprised from the reverse inclination thread | yarn 17 distribute | arranged to a direction.

  When the net shown in FIG. 6 is molded by the fusion method, the nozzle hole of the inclined thread 15 and the nozzle hole of the reverse inclined thread 17 are rotated in the reverse direction without rotating the nozzle hole of the warp thread 16, and at the intersection. What is necessary is just to fuse | melt each other.

  The order of lamination of the warp yarn 16, the inclined yarn 15 and the reverse inclined yarn 17 may be any, but in particular, the flow resistance in the intermediate layer can be reduced by configuring the second layer L2 with the warp yarn 16, so that the supply side The pressure loss of the flow path can be further reduced, and the inclined yarn 15 and the reverse inclined yarn 17 are in contact with the membrane surface, so that concentration polarization in the vicinity of the membrane surface can be effectively suppressed by the turbulent flow effect. .

  In addition, the intersection of the first layer L1 and the second layer L2 and the intersection of the second layer L2 and the third layer L3 may not coincide with each other, but the shape of the supply-side channel material is stable. In order to improve the property, it is preferable that the intersections of the two coincide.

  In the fifth configuration example, the thickness of the intersection of the warp yarn 16, the inclined yarn 15 and the reverse inclined yarn 17 is preferably 0.5 to 1.0 mm. Further, the yarn diameters of the warp yarn 16, the inclined yarn 15 and the reverse inclined yarn 17 are preferably 0.1 to 0.5 mm. Further, the hypotenuse length D in the unit plane shape is preferably 2 to 5 mm. The angle α formed by the inclined yarn 15 and the reverse inclined yarn 17 is preferably 60 to 120 °.

  The yarn diameters of the warp yarn 16, the inclined yarn 15 and the reverse inclined yarn 17 may be the same or different, but by increasing the warp yarn 16 constituting the second layer L2, the pressure loss of the supply-side flow path On the contrary, by making the warp yarn 16 constituting the second layer L2 relatively thin, concentration polarization in the vicinity of the film surface can be effectively suppressed by the turbulent flow effect.

  Examples and the like specifically showing the configuration and effects of the present invention will be described below. Needless to say, the present invention is not limited to such examples.

<Example 1 / Comparative Example 1>
FIG. 7 shows the flow rate and pressure loss when the supply-side flow path material shown in Table 2 was set in a parallel plate cell (C10-T; flow path width 35 mm, flow path length 135 mm) and pure water was flowed. . Other than the difference in the molding method and the difference in the weft diameter, the net has the same specifications, but the pressure loss in Example 1 is about 1/3 of that in Comparative Example 1.

＜実施例２／比較例２＞
表３に示した供給側流路材を用いて２３．２ｍ² のスパイラルエレメントを製作し、圧力容器に装壊した状態で純水を流したときの流量と圧力損失を図８に示した。実施例２における圧力損失は比較例２に対し約２／３以下の値になった。

<Example 2 / Comparative Example 2>
FIG. 8 shows the flow rate and pressure loss when a 23.2 m ² spiral element was manufactured using the supply-side channel material shown in Table 3 and pure water was allowed to flow in a state where the pressure element was destroyed. The pressure loss in Example 2 was about 2/3 or less that of Comparative Example 2.

尚、実施例２および比較例２のスパイラルエレメントについてＮａＣｌにおける性能を確認した結果、表４に示すように、比較例２に比べ阻止性能が劣ることはなく、濃度分極を維持するのに、充分な乱流効果が得られることを確認した。

As a result of confirming the performance in NaCl for the spiral elements of Example 2 and Comparative Example 2, as shown in Table 4, the blocking performance is not inferior to that of Comparative Example 2, and is sufficient to maintain the concentration polarization. It was confirmed that a turbulent flow effect was obtained.

＜実施例３／比較例３＞
表５に示した供給側流路材を平行平板セル（Ｃ１０−Ｔ；流路幅３５ｍｍ、流路長１３５ｍｍ）にセットし、純水を平均流速０．２ｍ／秒で流したときの圧力損失を図９に示した。成型方法の違いと単位平面形状の違いの他は同仕様のネットであるが、実施例３における圧力損失は比較例３に対し約６０％の値になった。

<Example 3 / Comparative Example 3>
Pressure loss when the supply side channel material shown in Table 5 is set in a parallel plate cell (C10-T; channel width 35 mm, channel length 135 mm) and pure water is flowed at an average flow rate of 0.2 m / sec. Is shown in FIG. Other than the difference in the molding method and the difference in unit plane shape, the net has the same specifications, but the pressure loss in Example 3 was about 60% of that in Comparative Example 3.

＜実施例４／比較例４＞
表６に示した供給側流路材を平行平板セル（Ｃ１０−Ｔ；流路幅３５ｍｍ、流路長１３５ｍｍ）にセットし、純水を平均流速０．２ｍ／秒で流したときの圧力損失を図１０に示した。成型方法の違いと単位平面形状の違いの他は同仕様のネットであるが、実施例４における圧力損失は比較例４に対し約６０％の値になった。

<Example 4 / Comparative Example 4>
Pressure loss when the supply side channel material shown in Table 6 was set in a parallel plate cell (C10-T; channel width 35 mm, channel length 135 mm) and pure water was flowed at an average flow rate of 0.2 m / sec. Is shown in FIG. Other than the difference in the molding method and the difference in unit plane shape, the net has the same specifications. However, the pressure loss in Example 4 was about 60% of that in Comparative Example 4.

  This supply-side channel material is not intended to limit its use at all, but when used in separation membrane elements mainly for the treatment of turbid wastewater (raw water) or elements used at low pressure The effect is demonstrated.

It is explanatory drawing which showed the net type (1st structural example) which is one Embodiment of this invention. It is explanatory drawing which showed the net type (2nd structural example) which is another form of implementation of this invention. It is explanatory drawing which showed the net type (3rd structural example) which is 3rd Embodiment of this invention. It is explanatory drawing which showed the net type (4th structural example) which is 4th Embodiment of this invention. It is explanatory drawing which showed another example of the net type (4th structural example) which is the 4th Embodiment of this invention. It is explanatory drawing which showed the net type (5th structural example) which is 5th Embodiment of this invention. It is explanatory drawing which illustrated the relationship between the supply water flow volume and pressure loss in Example 1 of this invention. It is explanatory drawing which illustrated the relationship between the supply water flow volume and pressure loss in Example 2 of this invention. It is explanatory drawing which showed the comparison of the pressure loss in Example 3 of this invention. It is explanatory drawing which showed the comparison of the pressure loss in Example 4 of this invention. It is explanatory drawing which showed the rhombus net type which is one Embodiment of the conventional product.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Warp 2 Weft 3 Thickness 4 Warp spacing 5 Weft spacing 6 Intersection angle 7 Warp meander angle 11 1st thread 11a Parallel part 11b of 1st thread 12 Inclined part 12 of 1st thread 2nd thread 12a Parallel part 12b of 2nd thread Inclined portion 15 of two threads Inclined thread 16 Warp thread 17 Reverse inclined thread

Claims (5)

  In a spiral separation membrane element in which one or more of a separation membrane, a supply-side flow channel material, and a permeation-side flow channel material are wound around a perforated hollow central tube, the supply-side flow channel material is: A spiral-type separation membrane element characterized by being a net obtained by fusion molding.   2. The spiral separation membrane according to claim 1, wherein the supply-side flow path material has a weft that intersects a supply liquid flow direction made thinner than a warp arranged along the supply liquid flow direction. element.   The spiral separation membrane element according to claim 1 or 2, wherein the supply-side flow path material is a net-shaped flow path material and has a structure in which the warps arranged along the supply liquid flow direction meander.   The supply-side flow path material has a two-layer structure including a first layer composed of a first yarn and a second layer composed of a second yarn, and each of the first yarn and the second yarn Repeatedly includes a parallel portion disposed substantially parallel to the feed liquid flow direction and an inclined portion disposed obliquely with respect to the feed liquid flow direction, and the parallel portion of the first yarn and the second yarn The spiral separation membrane element according to claim 1, wherein the parallel part is fused to form a hexagonal unit planar shape.   The supply-side flow path material is a warp yarn arranged substantially parallel to the supply liquid flow direction, an inclined yarn arranged obliquely with respect to the supply liquid flow direction, and the inclined yarn opposite to the supply liquid flow direction. The spiral-type separation membrane element according to claim 1, which has a three-layer structure composed of reversely inclined yarns arranged in an oblique direction.

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