JP5569238B2 - Zeolite membrane element - Google Patents

Description

The present invention relates to the structure of a zeolite membrane element.

  As a membrane element in which a sealing property between a tubular zeolite membrane element (hereinafter referred to as a membrane element) and a casing storing the tubular zeolite membrane element is ensured, for example, a membrane element 71 provided in a membrane module 70 shown in FIG. 6 is known. (Patent Documents 1 to 3 etc.).

  The membrane element 71 has a sealing portion 73 connected to one end of the zeolite membrane tube 72 and a connecting portion 74 connected to the other end. The connecting portion 74 is screwed and connected to the female screw portion 83 of the lid portion 82 of the casing 81 that houses the membrane element 71. The casing 81 includes a supply port 84 and a discharge port 85. A substance to be treated is supplied to the supply port 84. From the discharge port 85, the treated material from which the membrane permeation material contained in the material to be treated has been removed is discharged by the zeolite membrane tube 72. The sealing part 73 and the connection part 74 are comprised from either metals, such as SUS (for example, patent documents 1, 2), ceramics (for example, patent document 3), and fluororesin (for example, patent document 4), for example.

  Further, the outer peripheral surface in the vicinity of the connection between the zeolite membrane tube 72 and the sealing portion 73 and the connecting portion 74 is covered with a heat-shrinkable covering member 75 as shown in FIG. Further, a sealing member 76 made of a heat-shrinkable member or a grease material is interposed between the covering member 75 and the outer peripheral surface, so that the sealing performance between the zeolite membrane tube 72, the sealing portion 73, and the connecting portion 74 is achieved. Is appropriately secured (Patent Documents 1 and 2).

JP 2006-88079 A JP 2007-46755 A JP 2009-66528 A Japanese Patent No. 3617942 JP 2000-42387 A

  However, the membrane element 71 according to the prior art has the following problems.

  The membrane element 71 is likely to be distorted in the covering member 75 covering the outer peripheral surface on the other end side due to the weight of the sealing portion 73 connected to the one end side. As a result, it becomes easy for an external substance (substance to be treated) to enter the zeolite membrane tube 72 or to leak a membrane-permeable material from the zeolite membrane tube 72. In particular, when the membrane element 71 is disposed horizontally, distortion due to vibration in the radial direction of the zeolite membrane tube 72 becomes significant.

  Then, the zeolite membrane tube 72 may fall off from the connecting portion 74 due to the distortion. For example, the membrane element 71 may be provided in the casing 81 only by a fulcrum of the connection portion 74, and the load of the zeolite membrane tube 72 and the sealing portion 73 is applied to the connection portion 74, and the covering member 75 is distorted. This facilitates the detachment of the zeolite membrane tube 72 from the connecting portion 74. In addition, the sealing portion 73 may drop off from the zeolite membrane tube 72 due to fluctuations in the pressure difference between the inside and outside of the membrane element 71 (generation of reverse pressure). In particular, since the zeolite membrane tube 72 is made of a material different from that of the sealing portion 73 and the connecting portion 74, the degree of adhesion with the covering member 75 and the sealing member 76 is different, respectively, and the axial direction caused by the generation of vibration and back pressure The sealing portion 73 and the connecting portion 74 are likely to fall off from the zeolite membrane tube 72 due to the force.

  In the membrane element disclosed in Patent Document 4, the members corresponding to the sealing portion 73 and the connecting portion 74 are made of fluororesin, but the members are fixed to the outer peripheral surface near the end of the ceramic tube. Therefore, the problem of distortion due to radial vibration has not been solved.

  In the manufacturing process of the membrane element 71, the attachment of the sealing portion 73 and the connecting portion 74 to the zeolite membrane tube 72 after the zeolite film formation and the covering of the covering member 75 and the sealing member 76 may depend on manual work. If there are individual differences in manual work, the yield of the membrane element 71 becomes poor.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a zeolite membrane element capable of reducing the distortion of the connecting portion with the storage container and improving the yield of the product.

  Therefore, as an aspect of the zeolite membrane element of the present invention, a tubular member provided with a zeolite membrane on the outer peripheral surface, a sealing member made of a heat-shrinkable resin that seals one end of the tubular member, A tubular connecting member made of a heat-shrinkable resin that connects the tubular member and the storage container and supports the other end of the tubular member, the connecting member having the other end of the tubular member An outer tube portion to be inserted, and the other end portion of the tubular member is provided in the outer tube portion coaxially with the outer tube portion and circulates a membrane permeable substance in the tubular member and the outer tube portion. And an inner pipe part to be supported. According to the present invention, since the sealing member is made of the same heat-shrinkable resin as the connecting member and the inner tube portion and the outer tube portion of the connecting member support the tubular member, the diameter of the tubular member Directional vibration can be reduced.

  In the zeolite membrane element, an insertion portion into which the other end portion of the tubular member is inserted is formed in the outer tube portion, and a pipe portion on one end side of the inner tube portion is the other end portion of the tubular member. It is good to support in the state which pinched | interposed the other edge part of the said tubular member with the outer peripheral surface of the said piping part, and the inner peripheral surface of the said insertion part. The radial vibration can be further reduced.

  An example of the heat-shrinkable resin is a fluororesin.

  Therefore, according to the above invention, the distortion of the connecting portion with the storage container can be reduced and the yield of the zeolite membrane element can be improved.

The block diagram of the membrane module provided with the zeolite membrane element which concerns on embodiment of this invention. Sectional drawing which showed the state by which the one edge part of the zeolite membrane pipe was sealed by the sealing part. Sectional drawing which showed the state by which the other edge part of the zeolite membrane pipe was supported by the inner pipe part and outer pipe part of a connection part. Sectional drawing which showed the state by which the other edge part of the zeolite membrane tube was inserted in the insertion part of the outer tube part of a connection part. The photograph which showed the adhesion state of a zeolite membrane tube and a sealing part. The block diagram of the membrane module provided with the conventional zeolite membrane element. The schematic sectional drawing which showed the structure of the connection part of the zeolite membrane tube of a conventional zeolite membrane element, a sealing part, and a connection part.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Configuration of membrane element 1 according to an embodiment of the invention)
The membrane module 10 shown in FIG. 1 houses a plurality of membrane elements 1 according to an embodiment of the present invention in a casing 11 to which a substance to be treated is supplied.

  The membrane element 1 includes a zeolite membrane tube 2, a sealing portion 3, and a connection portion 4.

  The zeolite membrane tube 2 comprises a zeolite membrane on the outer peripheral surface of a cylindrical ceramic tube, for example. As the material of the ceramic tube body, any material can be applied as long as it is a porous material and can withstand the heat shrinkage temperature of the sealing portion 3 and the connecting portion 4. Examples of the porous material include ceramics exemplified by alumina and mullite. What is necessary is just to apply a well-known thing as said zeolite membrane according to the substance to be separated. Examples thereof include those made of zeolite of A type, T type, Y type, ZSM-5 type, and NaX type.

  As shown in FIG. 2, the sealing portion 3 is a member that seals one end of the zeolite membrane tube 2 and is made of a heat-shrinkable resin. The sealing part 3 seals one end of the zeolite membrane tube 2 by heat shrinkage. An example of the heat-shrinkable resin is a fluororesin. A well-known fluororesin may be applied. Specific examples of the fluororesin include tetrafluoroethylene-hexafluoropropylene copolymer resin (FEP), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin (PFA), and tetrafluoroethylene-ethylene copolymer resin (PFA). ETFE) and the like.

  The connecting portion 4 connects the zeolite membrane tube 2 and the casing 11, supports the other end of the zeolite membrane tube 2, and transfers a membrane permeation substance in the zeolite membrane tube 2 to the outside of the casing 11. And made of heat-shrinkable resin. The connection portion 4 is connected and fixed to the other end portion of the zeolite membrane tube 2 by heat shrinkage. The connecting portion 4 to which the zeolite membrane tube 2 is connected is screwed to the lid portion 12 of the casing 11. By setting the total length of the connecting portion 4 according to the total length of the zeolite membrane tube 2, it is possible to prevent the material to be treated from entering the zeolite membrane tube 2 and the leakage of the membrane permeation material.

  As illustrated in FIG. 3, the connection portion 4 includes an outer tube portion 5 and an inner tube portion 6.

  The outer tube portion 5 has a cylindrical shape. As shown in FIG. 4, the outer tube portion 5 is formed with an insertion portion 50 into which the other end portion of the zeolite membrane tube 2 to which the sealing portion 3 is not attached is inserted. Further, a male screw portion 51 is formed on the outer peripheral surface of the outer tube portion 5. The male screw portion 51 can be screwed with the female screw portion 13 formed on the lid portion 12 of the casing 11 shown in FIG. The diameters of the thread groove and the thread of the outer tube portion 5 are set so that the outer tube portion 5 can be screwed with the lid portion 12 even when thermally contracted. The outer tube portion 5 is configured by molding the same kind of fluororesin as the sealing portion 3.

  The inner tube portion 6 has a cylindrical shape and is provided in the outer tube portion 5 coaxially with the outer tube portion 5 as shown in FIG. The inner pipe part 6 circulates the membrane-permeable material in the zeolite membrane pipe 2 and transfers it to the outside of the casing 11. The inner tube portion 6 supports the other end portion of the zeolite membrane tube 2 inserted into the insertion portion 50 of the outer tube portion 5 with the outer tube portion 5. Specifically, as shown in the drawing, a pipe part on one end side of the inner pipe part 6 is inserted into the other end part of the zeolite membrane pipe 2, and the outer peripheral surface 61 of the pipe part and the inner peripheral surface 52 of the insertion part 50 are Supports the other end of the zeolite membrane tube 2 with the other end in between. The total length of the inner tube portion 6 is set to be approximately equal to the total length of the outer tube portion 5.

  Examples of the material constituting the inner pipe portion 6 include metals such as SUS. However, the inner pipe portion 6 may be made of the same material as that of the outer pipe portion 5, that is, a heat-shrinkable resin. When the inner tube portion 6 is made of a metal material, the inner tube portion 6 is inserted into the outer tube portion 5 by press-fitting. When the inner tube portion 6 is made of the same material as the outer tube portion 5, it may be provided in the outer tube portion 5 by press-fitting, but is formed integrally with the outer tube portion 5 by a known molding method. Also good.

  Incidentally, the volume of the insertion portion 50 of the outer tube portion 5 and the outer diameter of the inner tube portion 6 are set according to the outer diameter and inner diameter of the zeolite membrane tube 2 so that the material to be treated and the membrane of the zeolite membrane tube 2 can enter. Prevent leakage of permeation material.

(Method for manufacturing membrane element 1)
The manufacturing steps S1 to S3 of the membrane element 1 will be described.

  S1: The sealing part 3 is connected to one end part of the zeolite membrane tube 2, and the sealing part 3 is heat-treated. What is necessary is just to set the temperature and heating time which are applied to well-known technology (for example, patent document 1, 2) as this heating temperature and heating time. By this heating, the heat-shrinkable resin constituting the sealing portion 3 is thermally contracted and solidified to become an elastic body, and one end portion of the zeolite membrane tube 2 is sealed by the sealing portion 3. The sealing portion 3 may be further heat-treated after being fixed with a jig or the like so as to seal the end portion.

  S2: The connecting part 4 is attached to the other end of the zeolite membrane tube 2, and the connecting part 4 is heat-treated. By this heating, the heat-shrinkable resin constituting the connection portion 4 is thermally contracted and solidified to become an elastic body, and the connection portion 4 is connected and fixed to the other end of the zeolite membrane tube 2. What is necessary is just to set the heating temperature and heating time the same heating temperature and heating time as S3. Similarly to the sealing portion 3, the connecting portion 4 may be further fixed with a jig or the like and then heat-treated to be connected and fixed to the other end portion.

  S3: A zeolite membrane is formed on the outer peripheral surface of the zeolite membrane tube 2 to which the sealing portion 3 and the connecting portion 4 are connected through the processes of S1 and S2. A known technique may be applied to the method for forming the zeolite membrane. Examples of the well-known technique include a formation method in which a zeolite seed crystal supporting method disclosed in Patent Document 5 is combined with a hydrothermal synthesis method or a gas phase method.

(Description of the operation of the membrane module 10)
A plurality of membrane elements 1 manufactured in the above steps S1 to S3 are provided in a horizontally placed casing 11 like the membrane module 10 shown in FIG. The membrane element 1 is provided in the casing 11 by the connection portion 4 being screwed to the lid portion 12 of the casing 11. A vacuum pump P is connected to the end of the connecting portion 4 exposed from the casing 11 via a piping system 16.

  The substance to be treated is introduced into the casing 11 from the supply port 14. Since the internal pressure of the zeolite membrane tube 2 of the membrane element 1 is negative by the vacuum pump P than the pressure outside the zeolite membrane tube 2, the membrane-permeable material contained in the material to be treated introduced into the casing 11. Permeates inside the zeolite membrane tube 2. The permeable substance introduced into the zeolite membrane tube 2 is discharged from the connection portion 4 by the suction force of the vacuum pump P. On the other hand, the treated substance from which the permeable substance has been removed is discharged from the outlet 15 of the casing 11.

  When the substance to be treated is introduced from the supply port 14 while maintaining the flow velocity in the casing 11, the membrane element 1 vibrates in the radial direction due to the collision between the introduced substance to be treated and the sealing portion 3. Since the membrane element 1 has the sealing part 3 and the connection part 4 made of heat-shrinkable resin and the inner pipe part 6 of the connection part 4 supports the zeolite membrane pipe 2, the vibration in the radial direction is alleviated. Can do. Thereby, the distortion of the connection portion 4 is reduced as compared with the conventional one, and the dropping of the zeolite membrane tube 2 from the connection portion 4 is prevented.

(Effect of this embodiment)
As described above, according to the membrane element 1, the vibration in the radial direction of the zeolite membrane tube 2 can be relaxed, so that the distortion of the connecting portion 4 can be reduced.

  In particular, since the heat-shrinkable resin constituting the sealing portion 3 and the ceramic constituting the zeolite membrane tube 2 are in contact with each other without a grease material, the contact surfaces of both become resistant to displacement. Therefore, even when a reverse pressure is generated in which the internal pressure of the zeolite membrane tube 2 is higher than the external pressure, the sealing portion 3 can be prevented from falling off.

  Furthermore, since the sealing portion 3 of the membrane element 1 is made of a heat-shrinkable resin, the weight is greatly reduced. The membrane element 1 is cantilevered in the horizontal direction by the lid portion 12 of the membrane module 10. When a substance to be treated with a flow rate maintained is supplied from the supply port 14 of the casing 11, the sealing member is conventionally made of metal and thus has a large resistance, and its weight is a connecting portion with the casing 11 that is a fulcrum of the membrane element. Therefore, the connecting portion between the connecting portion and the tubular portion is easily loosened. Since the sealing part 3 according to the present embodiment is made of heat-shrinkable resin and is reduced in weight as described above, the burden on the connection part 4 that is the fulcrum of the membrane element 1 in the lid part 12 is reduced.

  Moreover, since the connection part 4 also consists of heat-shrinkable resin, weight reduction can be implement | achieved compared with the past, and the looseness of the connection part 4 by the flow of the to-be-processed substance provided in the casing 11 reduces more than the conventional membrane element. Further, since the connection portion 4 is not worn by the engagement with the lid portion 12 as in the prior art during the connection operation, the sealing performance with the lid portion 12 is improved. Further, since the connecting portion 4 includes the outer tube portion 5 and the outer tube portion 6, the strength of the connecting portion 4 is increased, and the overlap between the zeolite membrane tube 2 and the connecting portion 4 can be reduced. 2 increases the effective surface area of the zeolite membrane formed.

  FIG. 5 shows a photograph (the outer diameter of the zeolite membrane tube 2 is 12 mm) showing the state of adhesion between the zeolite membrane tube 2 and the sealing portion 3. As shown in FIG. 5, the adhesion at the interface between the sealing portion 3 and the zeolite membrane tube 2 was ensured. In addition, the adhesiveness of the interface between the connecting portion 4 and the zeolite membrane tube 2 was also confirmed in the same manner as the photograph in FIG.

  Further, in the conventional membrane element, when the dimensional accuracy of the zeolite membrane tube is low, leakage of the membrane permeation material or intrusion of the material to be treated is likely to occur due to the step difference of the sealing portion and the connection portion.

  On the other hand, in the membrane element 1 according to this embodiment, since the sealing part 3 and the connection part 4 are made of heat-shrinkable resin, the shape step can be sealed, and leakage of the membrane permeation substance or intrusion of the substance to be processed can be achieved. Can be prevented.

  Furthermore, in the conventional method for manufacturing a membrane element, grease or an adhesive may be used to connect the sealing member and the connecting member. There was a risk of adverse effects. Therefore, it is necessary to attach the sealing member and the connecting member after the zeolite membrane is formed on the tubular member, and the zeolite membrane may be damaged during the attaching operation, and the zeolite membrane may become defective.

  On the other hand, in the manufacturing methods S1 to S3 according to the embodiment of the present invention, the sealing part 3 and the connection part 4 are attached before forming the zeolite membrane, so that the handling during the manufacturing operation is easy and the damage to the zeolite membrane is performed. Can be prevented.

  Further, in the conventional membrane element manufacturing method, a zeolite membrane may be formed after coating a ceramic tube, which is a base material of the zeolite membrane tube, with a covering member and a sealing member. In this case, if grease is used for the sealing member, the grease component may be eluted in the process of film formation, which may cause film formation failure.

  On the other hand, since the sealing part 3 and the connection part 4 of the membrane element 1 according to the present invention are fixed to the zeolite membrane tube 2 by thermal contraction, a sealing member such as an adhesive or grease is not required. Thereby, in the manufacturing method of the membrane element 1 which concerns on this embodiment, even after attaching the sealing part 3 and the connection part 4 to the base material (ceramic pipe | tube) of the zeolite membrane pipe 2, a zeolite membrane on the surface of the said base material Can be formed.

  As described above, according to the manufacturing method of the present embodiment, the yield is improved and the production efficiency is increased.

1 ... Membrane element (Zeolite membrane element)
2 ... Zeolite membrane tube (tubular member)
3 ... Sealing part (sealing member)
4. Connection part (connection member)
10 ... Membrane module 11 ... Casing (storage container)

Claims (3)

A tubular member having a zeolite membrane on its outer peripheral surface;
A sealing member made of a heat-shrinkable resin that seals one end of the tubular member;
A tubular connection member made of a heat-shrinkable resin that connects the tubular member and the container and supports the other end of the tubular member;
The connecting member is
An outer tube part into which the other end of the tubular member is inserted;
The inner tube portion is provided in the outer tube portion coaxially with the outer tube portion and allows the membrane permeable substance in the tubular member to flow and supports the other end portion of the tubular member with the outer tube portion. A zeolite membrane element characterized by that. The outer tube portion is formed with an insertion portion into which the other end of the tubular member is inserted,
The pipe portion on one end side of the inner pipe portion is inserted into the other end portion of the tubular member, and the other end portion of the tubular member is sandwiched between the outer peripheral surface of the pipe portion and the inner peripheral surface of the insertion portion. The zeolite membrane element according to claim 1, wherein the zeolite membrane element is supported in a bent state. The zeolite membrane element according to claim 1 or 2, wherein the heat-shrinkable resin is made of a fluororesin.