JP2010042374A - Spiral type fluid separation element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a telescope preventive plate which enables the whole membrane unit to be uniformly used by making the inflow of raw water to the membrane unit uniform in the circumferential direction, and to provide a fluid separation element using the same. <P>SOLUTION: The telescope preventive plate of the spiral type fluid separation element comprises an inner circumferential annular part, an outer circumferential annular part and spoke parts connecting the annular parts. The end point of a center line in the cross face of the spoke part is located on a place different from a vertical line of the telescope preventive plate passing through a start point of the center line. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a spiral fluid separation element that is used by loading a plurality of membrane units in a pressure vessel in series into a plurality of pressure vessels. That is, the present invention relates to a spiral type fluid separation element in which flat membranes such as reverse osmosis membranes, ultrafiltration membranes, and microfiltration membranes are spirally wound.

  Separation membranes as water treatment means in seawater desalination and ultrapure water production applications in the semiconductor field, and in various water treatment applications including general brine desalination, organic matter separation, wastewater reuse, etc. The fluid separation process using the is used. In this separation process using a membrane, a spiral fluid separation element using a separation membrane is used, and its use is rapidly increasing.

  The spiral type fluid separation element has a structure in which a separation membrane is wound in a spiral shape around a collecting pipe together with a permeate flow path material and a raw liquid flow path material. As shown in FIG. 1, the spiral fluid separation element 1 includes a permeate flow path material 6 between envelope films formed by adhering three sides of a first separation membrane 4 and a second separation membrane 5 to each other. And a single unit or a plurality of units are prepared as a single unit and wound around the liquid collecting pipe 2 in a spiral shape. The envelope-like membrane is opened on the liquid collecting tube 2 side. The stock solution 3 is supplied from one end face of the spiral fluid separation element 1 and processed by the first and second separation membranes 4 and 5. The permeate 9 that has permeated through the separation membranes 4 and 5 is taken out from the liquid collection tube 2, and the stock solution 3 that has not permeated through the separation membranes 4 and 5 is discharged as a concentrate 8 from the other end face of the spiral fluid separation element 1. Is done.

  Usually, the spiral type fluid separation element has a configuration in which the outer side is hardened by an FRP shell made of glass fiber and epoxy resin, and telescope prevention plates are attached to both ends in the longitudinal direction.

  When actual fluid separation is performed using a spiral fluid separation element, a plurality of spiral fluid separation elements are arranged in series in a longitudinal direction in a pressure vessel and used as a separation membrane module. The Four to eight spiral fluid separation elements are used in the pressure vessel in order to effectively exert the separation performance by the separation membrane and to allow the amount of liquid necessary to prevent the separation membrane surface to be smeared on the separation membrane surface. Often used in series. The spiral type fluid separation elements loaded in series are arranged such that the telescope prevention plate at the end of the fluid separation element and the telescope prevention plate of the adjacent fluid separation element are in close contact with each other, and the liquid collecting pipe is connected by a connector. Connected by connecting.

  The telescope prevention plates are provided at both ends of the fluid separation element in order to prevent the phenomenon that the membrane unit inside the element collapses due to the stock solution flowing into the spiral fluid separation element at high pressure. In general, as shown in FIG. 2 (a), an inner peripheral annular portion 11 that engages with a liquid collecting pipe, an outer peripheral annular portion 12 having a diameter substantially equal to the diameter of the spiral fluid separation element, and the annular Spoke-type telescope prevention plate having a spoke portion 13 that connects the portions in a substantially radial direction, that is, in the direction substantially the same as the radius of the ring (Patent Document 1, Non-Patent Document 1), or a plate punched with a round hole, Or the round hole punching type telescope prevention board (patent document 2) comprised combining a spoke and a round hole punching board is used. About the shape of the said spoke part, as shown in FIG.2 (b), it is common that the cross section 14 is a rectangle perpendicular | vertical to the end surface 20 of a telescope prevention board. The hole is generally punched perpendicular to the end face of the telescope prevention plate.

However, since the membrane unit has an envelope shape opened on the side of the liquid collection tube as described above, there is a feature that the flow path resistance increases as the distance from the liquid collection tube also increases within the membrane unit. In the case of the shape of the spoke part or hole described above, the inflow of the stock solution to the end face of the membrane unit is concentrated in the vicinity of the liquid collecting pipe where the pressure loss is relatively low in the entire circumferential direction of the end face, and the contamination and wear of the part are lost. While it progresses faster compared to other parts of the unit, the inflow to the outer peripheral side far from the liquid collecting pipe is reduced, resulting in the problem that the entire membrane unit is not used uniformly in the circumferential direction. .
Special Table 2007-517661 JP 2005-111473 A Johnson J, “ILEK interlocking Endcaps Make Seawater Desalination Processing Easier Less Expensive”, [online], August 31, 2004, Dow Chemical Company (Dow Chemical Company), [Search June 13, 2008], Internet <URL: http://www.dow.com/webapps/lit/litorder.asp?filepath=liquidseps/pdfs/noreg/609- 00466.pdf>

  The present invention relates to a telescope prevention plate capable of uniformly using the entire membrane unit by making the inflow of the stock solution into the membrane unit uniform in the circumferential direction in a spiral type fluid separation element, and a fluid using the same It is to provide a separation element.

In order to achieve the above object, the present invention comprises the following configurations. That is,
(1) A telescope prevention plate for a spiral type fluid separation element, comprising an inner peripheral annular portion, an outer peripheral annular portion, and several spoke portions that connect these annular portions in a substantially radial direction. In at least one of the spoke portions, the end point of the center line in at least a part of the cross section thereof is at a position different from the perpendicular line of the end face of the telescope prevention plate passing through the start point of the center line. Telescope prevention plate.
(2) The telescoping prevention plate according to (1), wherein all of the transverse sections have the same shape in at least one of the several spoke portions.
(3) The telescoping prevention plate according to any one of (1) and (2), wherein the several spoke portions have the same shape in the total number.
(4) The distance between an arbitrary point on the center line and the perpendicular increases monotonously in a broad sense as the arbitrary point moves away from the starting point of the center line. The telescope prevention board in any one.
(5) A membrane unit including a separation membrane, a permeate flow channel material, and a stock solution flow channel material is wound around a liquid collection tube having a liquid collection hole, and the outer periphery of the wound membrane unit is an exterior body A spiral fluid separation element, wherein the telescopic prevention plate according to any one of (1) to (4) is provided on both end faces of the membrane unit and the outer package.
Consists of.

  By using the telescope prevention plate of the present invention for the spiral fluid separation element, when the stock solution flowing into the fluid separation element passes through the telescope prevention plate, the direction toward the outer peripheral side of the wound membrane unit, that is, By generating the swirl flow in the direction opposite to the winding direction of the membrane unit, the entire membrane unit can be used uniformly in the circumferential direction.

  As a result, the degree of fouling and wear of the entire membrane unit becomes uniform, and the life can be extended as compared with the conventional fluid separation element in which the vicinity of the liquid collecting pipe is used intensively. Also, compared with the conventional membrane unit, the inflow to the outer peripheral side increases and the pressure rises, while the inflow to the vicinity of the liquid collecting pipe decreases and the pressure decreases, so that the permeate flows easily in the membrane unit. Become.

  Furthermore, when a plurality of fluid separation elements provided with the telescope prevention plate of the present invention are arranged in series and used as a separation membrane module, the concentrated water flowing out from the end face on the inner peripheral side of the membrane unit of the previous fluid separation element is When flowing into the fluid separation element, the concentration is diffused by the effect of the telescope prevention plate, so that the recovery rate of the entire separation membrane module is improved.

  As shown in FIG. 3, the telescope prevention plate of the present invention has a diameter substantially equal to the diameter of the inner peripheral annular portion 11 that engages with a liquid collection pipe (not shown) and a spiral fluid separation element (not shown). It is a spoke-type thing which consists of the outer periphery annular part 12 which has these, and the spoke part 13 which connects these annular parts to a substantially radial direction.

  In the present invention, as shown in FIGS. 4A and 4B, for the purpose of uniform use of the membrane unit, the end point 19 of the center line 17 in the cross section 14 of the spoke portion is the start point 18 of the center line 17. The telescope prevention plate that passes through is located at a position different from the vertical line 21 of the end face. In particular, it is preferable that the distance between an arbitrary point on the center line 17 and the perpendicular line 21 increases monotonously in a broad sense as the arbitrary point moves away from the starting point 18 of the center line 17. The monotonic increase in a broad sense means that it does not decrease in all the sections, that is, does not always increase or decrease. By taking a shape that increases monotonically in a broad sense, the sign of the gradient of the speed of the stock solution with respect to the vertical line 21 is always constant, and the positive / negative of the slope of the speed does not roll in the middle, so that the stock solution can be efficiently turned. Examples of cross sections corresponding to this case are shown in FIGS.

  Here, the center line 17 is a line in which the midpoints of the line 15 corresponding to the upper surface and the line 16 corresponding to the lower surface in the cross section 14 are sequentially connected from the upstream side to the downstream side of the stock solution. Corresponds to the center line (average warp line, camber line). The midpoint is defined only when the parallel straight line of the end face 20 of the telescope prevention plate passes through both the line 15 corresponding to the upper surface and the line 16 corresponding to the lower surface. Of the two ends of the center line 17, the upstream side is called a start point 18 and the downstream side is called an end point 19. If the center line is not defined in the entire section from the start point to the end point, it may be determined only by the defined part.

  The cross-section is not limited to the shape shown in FIG. 5, and any shape can be adopted as long as it satisfies the above-described conditions of the present invention. In addition, the shape may be determined comprehensively in consideration of fluid characteristics, pressure resistance, workability (injection molding), and the like, such as designing the shape of the spoke part optimal for uniform use of the membrane unit.

  Note that it is preferable that all the spoke portions have the same shape and are arranged in a circular symmetry because the flow of the stock solution into each membrane unit in the spiral fluid separation element becomes uniform. Further, the shape of the cross section of each spoke part may be the same throughout the spoke part or may change in the longitudinal direction. Is preferable from the viewpoint of uniforming.

  Although the material which comprises a telescope prevention board is not specifically limited, Usually, what is necessary is just to select resin suitable for injection molding from a viewpoint of mass production, cost, and weight reduction. Furthermore, since it is hard to be attacked by various substances contained in the undiluted solution, it is preferable to have excellent chemical resistance. For example, it is possible to use acrylonitrile butadiene styrene copolymer (ABS), polystyrene (PS), polypropylene (PP), polyethylene (PE), polytetrafluoroethylene (PTFE), or a composite material (polymer alloy, etc.) thereof. it can.

  The spiral type fluid separation element of the present invention has a structure in which a separation membrane is spirally wound around a collecting pipe together with a permeate channel material and a raw solution channel material. As shown in FIG. 1, the spiral fluid separation element 1 includes a permeate flow path material 6 between envelope films formed by adhering three sides of a first separation membrane 4 and a second separation membrane 5 to each other. One or a plurality of units are prepared as a single unit, and the undiluted liquid flow path material 7 is wound around the liquid collecting pipe in a spiral shape, and the telescope prevention plate 10 of the present invention is provided at both ends in the longitudinal direction. The outer periphery is solidified by glass fiber and epoxy resin FRP shell.

  As the separation membrane, a reverse osmosis membrane (RO membrane) or a nanofiltration membrane (NF membrane) flat membrane having a porous support layer and a separation functional layer on the membrane support layer is used. As a material for the separation functional layer, a cross-linked aromatic polyamide is widely used, but the material is not limited to this in the present invention.

  As the permeate channel material, it is preferable to use a non-woven fabric in terms of satisfying sufficient water permeability and strength capable of withstanding deformation under high pressure. The material is not particularly limited, but it is preferable to use polyester as a material that has good processability when made into a nonwoven fabric, high strength, and little elution of components into the permeate.

  As for the stock solution channel material, it is preferable to use a mesh-like material as a shape that can widen the flow of the stock solution and has a low flow resistance. The material is not particularly limited, but polyethylene (PE) or polypropylene (PP) is preferably used from the viewpoint of not damaging the film and cost.

  The collecting tube is a circular tube in which a plurality of holes for collecting liquid are formed in one or more rows in a direction parallel to the axis, and the material is not particularly limited, but the strength is high and the weight is low. It is preferable to use a certain polyphenylene oxide resin (PPO).

  As a method of winding the membrane unit around the liquid collecting tube, for example, there is a method of winding in a roll while pressing with a suitable pressure with a pair of nip rolls on a rotating drive roll. The method is not particularly limited as long as the circularity can be secured within a range that does not hinder the loading of the pressure vessel.

  A telescope prevention plate is attached to both ends of the roll-like material formed in this way, with its inner peripheral annular part moved along the collecting tube and translated, and further, glass fiber impregnated with epoxy resin is wrapped around the outer periphery. Then, it is cured by heating to form a shell and fix the telescope prevention plate.

  According to the present invention, it is not necessary to change the configuration and manufacturing method of the conventional spiral fluid separation element, and there is no limitation, so that a spiral fluid separation element that can uniformly use the entire membrane unit is easily realized. can do.

It is a general | schematic partial expanded view of the spiral type fluid separation element manufactured by one embodiment of this invention. It is the figure which showed the example of the conventional telescope prevention board, (a) is a front view, (b) is a cross section in AA of (a). It is the front view which showed the example of the telescope prevention board of this invention. It is the figure which showed the example of the telescope prevention board of this invention, (a) is an example of the cross section in AA of FIG. 3, (b) is the other example of the cross section in AA of FIG. FIG. It is the figure which showed the various cross sections of the spoke part of the telescope prevention board of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Spiral type fluid separation element 2 Collection pipe 3 Stock solution 4 1st separation membrane 5 2nd separation membrane 6 Permeate flow path material 7 Stock solution flow path material 8 Concentrated liquid 9 Permeate 10 Telescope prevention plate 11 Inner ring Part 12 Peripheral annular part 13 Spoke part 14 Cross section 15 Line 16 corresponding to the upper surface Line 17 corresponding to the lower surface 17 Center line 18 Start point 19 End point 20 End face 21 of the telescope prevention plate End face of the telescope prevention plate passing through the start point of the center line Vertical line

Claims (5)

  A telescope prevention plate for a spiral fluid separation element, comprising an inner peripheral annular portion, an outer peripheral annular portion, and several spoke portions that connect the annular portions in a substantially radial direction, and the several spoke portions Telescope prevention characterized in that at least one of the end points of the center line in at least a part of the cross section thereof is at a position different from the vertical line of the end face of the telescope prevention plate passing through the start point of the center line. Board.   The telescope prevention plate according to claim 1, wherein at least one of the several spoke parts has the same cross-sectional shape.   The telescoping prevention plate according to claim 1, wherein the several spoke parts have the same shape in all the number.   4. The telescope according to claim 1, wherein a distance between an arbitrary point on the center line and the perpendicular increases monotonously in a broad sense as the arbitrary point moves away from a starting point of the center point. Prevention plate.   A membrane unit including a separation membrane, a permeate flow channel material, and a stock solution flow channel material is wound around a liquid collection tube having a liquid collection hole, and the outer periphery of the wound membrane unit is covered with an exterior body. A spiral fluid separation element, wherein the telescope prevention plate according to any one of claims 1 to 4 is provided on both end faces of the unit and the exterior body, respectively.

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