JP2006212514A - Fluid separation element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid separation element which is prevented from bursting during operation, concretely is prevented from bursting because such circumstances that end plates are tightly adhered to each other to form a liquid-tight state and a pressure between a pressure vessel and the fluid separation element is drastically different from the pressure of raw water is produced when the fluid separation elements are connected with each other. <P>SOLUTION: In the fluid separation element which is formed by spirally winding a separation membrane, raw water channel material and water permeate channel material, is loaded into the pressure vessel and is used, a channel which communicates with the raw water side channel of the fluid separation element and a gap between the fluid separation element and the pressure vessel is secured and the channel which communicates with the raw water side channel of the fluid separation element and the gap between the fluid separation element and the pressure vessel is disposed on a telescope prevention plate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  In recent years, separation in various fluid separation fields using membrane permeates or concentrated liquids such as seawater desalination and ultrapure water applications in the semiconductor field, as well as general brine applications, organic matter separation, wastewater reuse, etc. The use of membrane-based fluid separation elements is increasing rapidly.

  Examples of the form of the fluid separation element include those using hollow fiber membranes, flat membrane plate frame types, and spiral types. Among these, the spiral type fluid separation element has a structure in which a separation membrane is spirally wound around a water collecting pipe together with a permeate flow path material and a supply liquid flow path material. As shown in FIG. 1, the spiral type fluid separation element has a permeate flow path material 5 between an envelope membrane formed by adhering three sides of a first separation membrane 3 and a second separation membrane 4 to each other. A single unit or a plurality of units are prepared as a single unit by sandwiching them and the supply liquid channel material 6 and wound around the water collecting pipe 1 in a spiral shape. The envelope-like membrane is opened on the water collecting pipe 1 side. The supply liquid 2 is supplied from one end face of the fluid separation element and is processed by the first separation membrane 3 and the second separation membrane 4. The permeated liquid 8 that has passed through the separation membranes 3 and 4 is taken out from the water collecting pipe 1, and the supply liquid 2 that has not passed through the separation membranes 3 and 4 is discharged as a concentrated liquid 7 from the other end face of the fluid separation element.

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

The telescope prevention plate on the upstream side of the fluid separation element has a seal member called a brine seal, which prevents the raw water from short-passing to the gap between the outer FRP of the fluid separation element and the pressure vessel. The brine seal may be an O-ring or the like, but a U seal or the like is often used because of its ability to be loaded into a pressure vessel. When the fluid flows from the upstream side, the U seal opens to seal the telescope prevention plate and the pressure vessel in a fluid-tight manner. The flow from the downstream side cannot be liquid-tightly sealed due to its structure.
At the time of use, about 1 to 6 bottles are used in series in a pressure vessel, and a large number of the pressure vessels are installed on a rack to handle a large volume of processing.

  Normally, when a plurality of fluid separation elements are loaded in series, of two continuous fluid separation elements, the upstream fluid separation element is the downstream telescope prevention plate and the downstream fluid separation element is the upstream telescope. Since the fluid can flow into the space between the outside of the upstream fluid separation element and the pressure vessel from the clearance of the scope prevention plate, the inside and outside of the FRP outside the fluid separation element have the same pressure.

However, in the actual operation situation, there are rare cases where the telescope prevention plates of the plurality of fluid separation elements loaded in the pressure vessel are in close contact due to some reason such as the structure of the apparatus, the operation situation, the use situation, etc. Sometimes. In some situations, the brine seal may seal the fluid from the downstream side in a liquid-tight manner.
At this time, a pressure difference is generated between the inside and outside of the FRP shell of the fluid separation element. That is, the outside of the FRP is the atmospheric pressure at the time of loading, the inside is the raw water pressure, and reaches 6 to 9 MPa for seawater. For this reason, when this state occurs, the outer FRP portion of the fluid separation element may not withstand the pressure difference and may rupture, causing damage to the encapsulating film and causing a significant performance degradation.
Conventionally, there is a fluid separation element that communicates the inside and outside of the outer FRP shell of the fluid separation element (see, for example, Patent Document 1). However, the stock solution passage is opened in the shell portion behind the brine seal, and the shell and the pressure vessel The purpose is to prevent the raw water from staying in the gap. In this case, the raw water is short-passed from the opening, and the membrane surface portion of the fluid separation element cannot be flowed effectively, and the performance deteriorates. .

In addition, the telescope prevention plate can be easily sealed at the time of connection (for example, see Non-Patent Document 1), or a type that prevents the drift of raw water by opening countless holes in the telescope prevention plate (for example, see Non-Patent Document 2). ) Is used, but in any case, there is a risk of end plates coming into close contact with each other and causing rupture.
Japanese Utility Model Publication No. 5-93530 Johnson J Irek interlocking Endcaps Make Seawater Desalination Processing iSealess Desalination Processing Easier Less Expensive [online], Dow Chemical Company, August 2004 31st, Dow Chemical Company website [searched on January 20, 2005], Internet <URL http://www.dow.com/webapps/lit/litorder.asp?filepath=liquidseps/pdfs/noreg/609-00466. pdf> Hydronautics (HYDRANATUICS), FLUSH CUT ELEMENT DESIGN, Technical Service Bulletin, [online] September 2002, Hydronautics homepage [searched January 20, 2005] Internet <URL: http://www.membranes.com/docs/tsb/tsb103.pdf>

  An object of the present invention is to prevent the fluid separation element from bursting during operation. Specifically, when connected, the end plates are in close contact with each other and become liquid-tight, so that the pressure between the pressure vessel and the fluid separation element is significantly different from the raw water pressure, preventing the fluid separation element from being damaged. Is an issue.

In order to solve the above problems, the present invention has the following configuration. That is,
(1) In a fluid separation element in which a separation membrane, a raw water flow path material, and a permeate flow path material are spirally wound and loaded into a pressure vessel, the raw water side flow path of the fluid separation element, the fluid separation element, and the pressure vessel A passage communicating with a gap between the fluid separation element and a passage communicating with the gap between the raw water side flow path of the fluid separation element and the fluid separation element and the pressure vessel is provided in the telescope prevention plate. A fluid separation element.

  (2) The passage that communicates with the raw water-side flow path of the fluid separation element and the gap between the fluid separation element and the pressure vessel is a hole that is opened on the end side in the longitudinal direction from the brine seal loading seal portion of the telescope prevention plate. (1) The fluid separation element according to (1).

(3) The raw water side channel of the fluid separation element and the passage communicating with the gap between the fluid separation element and the pressure vessel are grooves carved on the surface of the telescope prevention plate. Fluid separation element.
(4) A flow path communicating with the raw water side flow path of the fluid separation element and the gap between the fluid separation element and the pressure vessel is formed between the telescope prevention plates by the protrusions provided on the surface of the telescope prevention plate. The fluid separation element according to (1), wherein the fluid separation element is a formed gap.

(5) In the fluid separation element that is used by winding the separation membrane and the raw water passage material in a spiral shape and loading the pressure vessel, the raw water side passage of the fluid separation element, the fluid separation element, and the pressure vessel A passage communicating with the gap between the raw water side flow path of the fluid separation element and the passage communicating with the gap between the fluid separation element and the pressure vessel is a downstream telescope prevention plate or telescope prevention plate. A fluid separation element provided in the vicinity.
Consists of.

  The effect obtained by the present invention is that the formation of a liquid-tight state can be prevented and the fluid separation element can be prevented from rupturing by providing holes, grooves, convex portions, etc. in the telescope prevention plate or the outer shell.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The fluid separation element to which the present invention is applied is mainly a spiral type fluid separation element, but has an outer shell, is loaded in a pressure vessel, and prevents brine from flowing into the gap between the pressure vessel and the fluid separation element. As long as a seal-like member is used, the form is not particularly limited.

In normal operation, there is no particular sealing means between the fluid separation elements loaded in series as shown in FIG. 2 and the liquid separation element is not liquid-tight. And no force in the burst direction is applied to the outer shell. However, there are rare cases in which the space between the downstream telescope prevention plate of the upstream fluid separation element and the upstream telescope prevention plate of the downstream fluid separation element becomes liquid-tight due to operating conditions, substances in the raw water, and other reasons. . Even in this case, the pressure of raw water should reach the most upstream fluid separation element from the downstream side of the most downstream fluid separation element through the gap between the outer shell of the fluid separation element and the pressure vessel. For example, as shown in FIG. When the downstream side of the most downstream fluid separation element and the lid of the pressure vessel become liquid-tight for some reason due to thrust ring, etc., or when the brine seal is sandwiched between the fluid separation element and the pressure vessel, from downstream to upstream If the brine seal is liquid-tightly sealed regardless of the upstream or downstream direction, such as an O-ring, a pressure difference is generated between the gap between the pressure vessel and the fluid separation element and the inside of the fluid separation element. Here, the outer shell is usually made of glass fiber that is hardened with a resin and FRP is often used.
Since the pressure difference between the inside and outside of the outer shell of the fluid separation element becomes the raw water pressure, and particularly in seawater desalination, the pressure difference is about 6 MPa.

The main object of the present invention is to provide a communicating passage so as not to cause a pressure difference. As a form thereof, for example, as shown in FIG. 4, the telescope prevention plate communicates with the gap between the pressure vessel and the fluid separation element. There is a method of providing a passage.
At this time, if the purpose is to prevent rupture only, the positional relationship between the brine seal and the communication passage is not a concern. However, the brine seal originally has a short path of raw water in the gap between the fluid separation element and the pressure vessel. Since it aims at preventing the performance of the fluid separation element from deteriorating, it is desirable that at least the upstream telescope prevention plate of the fluid separation element does not have a communication passage immediately downstream of the brine seal.

The number of communication passages, holes, convex portions, etc. is about 1 to 24, preferably about 4 to 12, and a method of installing in accordance with the position of ribs or the like in terms of design is preferable in production. Holes, grooves, a total area of the communication passage, such as the convex portion, since the purpose of fluid to the passing to equalize the pressure, may be a relatively small area, approximately the object if 2 mm ² or more Can be achieved. The upper limit of the total area is not limited in terms of function, but if it is increased more than necessary, the end plate portion becomes large and the film area is inevitably reduced, so it is substantially up to about 6000 mm ² . Actually, about ² to 100 mm ² is more preferable in consideration of the function and the influence on the membrane area.
The shape of the hole, groove, and convex part is round, triangular, square, semicircle, logo, stamp, pattern, etc., as long as it can be a communication path to the outer shell and telescope prevention plate to secure the flow path. From the above point of view, it is easy to implement a round groove if it is a hole, a semicircle if it is a groove, or a rectangular groove.

  If the purpose is merely to prevent bursting, there is a method in which a gap is formed between the elements by giving the connector a form such as a collar, but this is not advantageous in terms of overall length and part workability. In addition, there is a method in which a thin ring-shaped member is sandwiched between the fluid separation elements at the time of loading, but this is not advantageous from the viewpoint of workability and the change in the total length.

  The present invention is applied to an element of a type in which the outer peripheral portions of the telescope prevention plate surfaces of two adjacent fluid separation elements are substantially in contact with each other or are substantially in contact with each other when a plurality of fluid separation elements are loaded. Is done. Usually, this type has many types in which the permeate of adjacent elements is connected by a connector that enters the inner diameter of the central pipe.

In general, the same telescope prevention plate is used for both upstream and downstream by injection molding, and it is not economical to produce a telescope prevention plate of a different type from that for upstream and downstream. Therefore, when providing the communication path in the telescope prevention plate, it is desirable to install the communication path on the end side in the longitudinal direction of the fluid separation element from the brine seal.
As a form of the communication passage, there is a hole, but for the purpose of the present invention, a communication passage may be formed between two fluid separation elements in series. As a specific form, as shown in FIG. 5, a groove is formed on the surface of the telescope prevention plate, so that a communication path to the gap between the fluid separation element and the pressure vessel is established between two fluid separation elements in series. Can be formed. Further, by providing a convex portion on the surface of the telescope prevention plate as shown in FIG. 6, a communication path to the gap between the fluid separation element and the pressure vessel is formed between two fluid separation elements that are similarly connected in series. Can do.

  As the form of the groove, the radial shape is easy in design, but it may be a parallel groove due to the convenience of die-cutting for injection molding or for other reasons, and it is only necessary to form a communication path for the radial number. It is not limited by the figure.

  The shape of the convex portion may also be a shape that forms a communication path, for example, the surface of the telescope prevention plate may be provided with a company logo mark or the like, or it may look like a design pattern The size and shape are not particularly limited by the drawings.

  In the example of FIG. 5, the same telescope prevention plate is used in the upstream and downstream, but the object of the present invention is also an example in which a communication passage is provided in either the upstream or downstream telescope prevention plate as shown in FIG. 7. Can be achieved.

  Considering from the viewpoint of securing the communication path, it is not necessary to stick to the telescope prevention plate, and the object of the present invention can be achieved by a method of providing a communication path such as a hole in the outer shell of the fluid separation element as shown in FIG. be able to. At this time, it is desirable to install a communication passage in the downstream portion of the fluid separation element for the purpose of preventing a short path of raw water.

There are various convex portions such as a semicircle, a triangle, a square, a logo, and a pattern, but the present invention is not limited to this. For size, total ^area, it is 2mm ² ~6000mm 2 about. More preferably, it is about ² to 100 mm ² , but is not limited thereto.

Example 1
Two φ1 mm holes were opened at 180 ° opposite to each other at 30 mm from the downstream telescope prevention plate of the outer shell of the fluid separation element.

  In order to simulate a pressure difference between the inside and outside of the fluid separation element, a brine seal was mounted on the upstream and downstream of the fluid separation element as shown in FIG.

  The raw water supply conditions were set to be a brine flow rate of 130 L / min, seawater with a total solute concentration of 3.5 wt%, and 9 MPa, and the operation was started.

  After 60 minutes, the fluid separation element was taken out from the pressure vessel, and the damage state was confirmed. The fluid separation element was not damaged, and the outer shell was also observed. As a result, no evidence of breakage was found.

(Example 2)
Twelve semicircular grooves having a depth of 1.5 mm were radially formed on the surface of the telescope prevention plate.

  The brine seal was processed so as to be liquid-tight in both the upstream and downstream, and attached to the upstream portion of the fluid separation element. Six fluid separation elements were loaded in a series of six pressure vessels. At this time, a thrust ring having no communication path between the inside and outside of the fluid separation element row is mounted on the upstream and downstream sides, the fluid separation element row is compressed by 3 mm with the lid of the pressure vessel, and the inside of the fluid separation device and the pressure vessel The gap was made substantially liquid-tight.

  The raw water supply conditions were as follows: brine 80 L / min, seawater with a total solute concentration of 3.5% by weight, and 5.5 MPa, starting from 5 minutes from the start.

  After 15 minutes, the fluid separation element was taken out from the pressure vessel, and the damage state was confirmed. There was no damage to the fluid separation element, and the outer shell was indirect, and no evidence of breakage was found.

(Example 3)
As shown in FIG. 6, convex portions having a height of 1.5 mm were provided radially on the telescope prevention plate.

  The brine seal was processed so as to be liquid-tight in both the upstream and downstream, and attached to the upstream portion of the fluid separation element. Six fluid separation elements were loaded in a series of six pressure vessels. At this time, a thrust ring having no communication passage on the inside and outside is installed on the upstream and downstream sides of the fluid separation element array, and the fluid separation element array is compressed by 3 mm with the lid of the pressure vessel, and the gap between the inside of the fluid separation element and the pressure vessel It was made to be substantially liquid-tight.

  The raw water supply conditions were as follows: brine 80 L / min, seawater with a total solute concentration of 3.5% by weight, and 5.5 MPa, starting from 1 minute from the start.

  After 15 minutes, the fluid separation element was taken out from the pressure vessel, and the damage state was confirmed. There was no damage to the fluid separation element, and the outer shell was indirect, and no evidence of breakage was found.

Example 4
Only the downstream side of the telescope prevention plate was cut radially by 1.5 mm as shown in FIG.

  The brine seal was processed so as to be liquid-tight in both the upstream and downstream, and attached to the upstream portion of the fluid separation element. Six fluid separation elements were loaded in a series of six pressure vessels. At this time, a thrust ring having no communication passage on the inside and outside is installed on the upstream and downstream sides of the fluid separation element array, and the fluid separation element array is compressed by 3 mm with the lid of the pressure vessel, and the gap between the inside of the fluid separation element and the pressure vessel It was made to be substantially liquid-tight.

  The raw water supply conditions were as follows: brine 80 L / min, seawater with a total solute concentration of 3.5% by weight, and 5.5 MPa, starting from 5 minutes from the start.

  After 15 minutes, the fluid separation element was taken out from the pressure vessel, and the damage state was confirmed. There was no damage to the fluid separation element, and the outer shell was indirect, and no evidence of breakage was found.

(Example 5)
Four equidistant holes were formed 20 mm from the downstream telescope prevention plate of the outer shell of the fluid separation element every 90 degrees of φ2 mm holes.

  In order to simulate a pressure difference between the inside and outside of the fluid separation element, a brine seal was mounted on the upstream and downstream of the fluid separation element as shown in FIG.

  The raw water supply conditions were set to be a brine flow rate of 130 L / min, seawater with a total solute concentration of 3.5 wt%, and 9 MPa, and the operation was started.

  After 60 minutes, the fluid separation element was taken out from the pressure vessel, and the damage state was confirmed. The fluid separation element was not damaged, and the outer shell was also observed. As a result, no evidence of breakage was found.

(Comparative Example 1)
A normal fluid separation element (TM820-400 manufactured by Toray Industries, Inc.) having no communication hole of the present application was prepared for both the outer shell and the end plate.

  In order to simulate a pressure difference between the inside and outside of the fluid separation element, a brine seal is mounted on the fluid separation element above and downstream as shown in FIG.

  The raw water supply conditions were set to be a brine flow rate of 130 L / min, seawater with a total solute concentration of 3.5 wt%, and 9 MPa, and the operation was started.

  After 10 seconds, a bursting sound was heard, the operation was stopped, and the fluid separation element was taken out of the pressure vessel. As a result, the outer shell of the fluid separation element was ruptured, and the inner membrane was ruptured.

(Comparative Example 2)
Six normal fluid separation elements (TM820-400, manufactured by Toray Industries, Inc.) having no communication hole of the present application in both the outer shell and the end plate portion were prepared.

  The brine seal was processed so as to be liquid-tight in both the upstream and downstream, and attached to the upstream portion of the fluid separation element. Six fluid separation elements were loaded in a series of six pressure vessels. At this time, a thrust ring is mounted on the upstream side and the downstream side of the fluid separation element row, the fluid separation element row is compressed by 3 mm with the lid of the pressure vessel, and the space between the inside of the fluid separation device and the pressure vessel becomes substantially liquid tight. I did it.

  The raw water supply conditions were as follows: brine 80 L / min, seawater with a total solute concentration of 3.5% by weight, and 5.5 MPa, and 5 minutes from the start.

  Since there was a popping sound 3 times between 5 and 6 minutes after the start, the device was stopped and the fluid separation element was taken out of the pressure vessel to check the damage status. The outer shells of a total of three fluid separation elements, the first, third, and fourth, from the upstream side burst, and the inner membrane was torn out.

It is a general | schematic partially expanded view of the fluid separation element manufactured by one embodiment of this invention. It is the figure loaded in series using the end plate of a conventional shape. It is a figure which uses the thrust ring in the most downstream of the downstream fluid separation element of the fluid separation element loaded in series using the end plate of the conventional shape. It is the figure which opened the communicating path in the clearance gap between a pressure vessel and a fluid separation element in a telescope prevention plate. It is the figure which cut the groove | channel on the surface of the telescope prevention board and loaded in series. It is the figure which made the convex part on the surface of the telescope prevention board and loaded in series. It is the figure which carved the groove | channel only in the downstream surface of the telescope prevention board, and was loaded in series. It is the figure which opened the channel | path connected to the outer shell near downstream telescope prevention board. It is the figure which carried out the hole seal of the φ2 in the outer shell of the place 20 mm from the downstream telescope prevention plate, and was filled with the brine seals on both the upstream and downstream sides. It is the figure which mounted | wore with the telescope prevention board of the upstream and downstream both sides of the fluid separation element with a brine seal in the comparative example, and was loaded.

Explanation of symbols

1: Water collecting pipe 2: Supply liquid 3: First separation membrane 4: Second separation membrane 5: Permeate flow path material 6: Supply liquid flow path material 7: Concentrated liquid 8: Permeate 9: Telescope prevention plate 10: brine seal 11: outer shell 12: gap 13: communication passage 14: thrust ring 15: groove 16: convex portion

Claims (5)

In the fluid separation element that is used by winding the separation membrane, the raw water flow path material, and the permeate flow path material in a spiral shape and loading the pressure container, the flow separation between the raw water side flow path of the fluid separation element, the fluid separation element, and the pressure vessel A passage communicating with the gap is ensured, and a passage communicating with the gap between the raw water-side flow path of the fluid separation element and the fluid separation element and the pressure vessel is provided in the telescope prevention plate. Fluid separation element. The passage connected to the raw water side flow path of the fluid separation element and the gap between the fluid separation element and the pressure vessel is a hole opened on the end side in the longitudinal direction from the brine seal loading seal portion of the telescope prevention plate. The fluid separation element according to claim 1. 2. The fluid separation according to claim 1, wherein the passage communicating with the raw water side channel of the fluid separation element and the gap between the fluid separation element and the pressure vessel is a groove carved in the surface of the telescope prevention plate. element. A gap formed between the telescope prevention plate with a passage communicating with the raw water side flow path of the fluid separation element and a gap between the fluid separation element and the pressure vessel formed by protrusions provided on the surface of the telescope prevention plate The fluid separation element according to claim 1, wherein: In the fluid separation element that is used by winding the separation membrane, the raw water flow path material, and the permeate flow path material in a spiral shape and loading the pressure container, the flow separation between the raw water side flow path of the fluid separation element, the fluid separation element, and the pressure vessel A passage communicating with the gap is secured, and the passage communicating with the gap between the raw water side flow path of the fluid separation element and the fluid separation element and the pressure vessel is located near the telescope prevention plate on the downstream side or the telescope prevention plate. A fluid separation element provided.

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