JP2011025154A - Hollow fiber membrane module for moisture exchange - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hollow fiber membrane module for moisture exchange which can sufficiently humidify dried oxidant gas supplied into hollow fiber membranes, and can suppress the unevenness of filled hollow fiber membranes to allow the humidified off gas to flow uniformly. <P>SOLUTION: The hollow fiber membrane module for moisture exchange includes a cylindrical case, a plurality of the hollow fiber membranes axially extended and filled in a space inside the case, sealing portions for fixing the hollow fiber membranes and sealing the space at the both ends of the case, an introduction port formed on one side of the case, a discharge port formed on the side opposite to the side formed with the introduction port, a first fluid path extending from one end side to the other end side of each of the hollow fiber membranes through the hollow inside thereof, a second fluid path extending from the introduction port to the discharge port through the inside of the space and the outside of the hollow fiber membranes, a plurality of porous members axially extending in the space and having planes traversing the second fluid path, and support members axially extending in the space, coming into contact with and supporting the porous members and having a rigidity higher than that of the porous members. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a moisture exchange hollow fiber membrane module suitable for use in, for example, a fuel cell system, and more particularly to a technique for improving humidification efficiency with respect to a humidified gas.

  As a fuel cell, a stacked body in which separators are stacked on both sides of a flat membrane electrode assembly (MEA) is used as a unit cell, and a fuel cell stack is formed by stacking several unit cells, for example, several hundred layers. A fuel cell configured as is known. The membrane electrode structure has a three-layer structure in which an electrolyte membrane made of an ion exchange resin or the like is sandwiched between a pair of electrodes constituting a positive electrode (air electrode, cathode) and a negative electrode (fuel electrode, anode). According to such a fuel cell, for example, when a fuel gas is caused to flow through a gas passage facing the gas diffusion electrode on the fuel electrode side and an oxidant gas is caused to flow through a gas passage facing the gas diffusion electrode on the air electrode side, A chemical reaction occurs, generating electricity.

  Here, in order to stabilize the electrochemical reaction as described above, it is desirable that the membrane electrode structure is wet. For example, Patent Document 1 discloses that an anode exhaust gas after use in which the partial pressure of water vapor is increased by adding power generation generated water as water vapor to the fuel gas in the fuel gas flow path is used as a humidified gas, and unused fuel. A fuel cell system for humidifying gas is disclosed.

  By the way, in recent years, the membrane electrode structure tends to become thinner as the performance of the fuel cell becomes higher, and the phenomenon that the water generated by the electrochemical reaction and coming out to the air electrode side moves to the fuel electrode side seems to occur. It has become. For this reason, when the fuel gas is humidified, a wet state of the fuel electrode becomes excessive, and a phenomenon called flooding occurs in which contact between the fuel and the fuel electrode is hindered. On the other hand, on the air electrode side, it is known that there are cases in which the electrochemical reaction is not so hindered even when the degree of wetting is excessive. Therefore, recently, a technique for humidifying the oxidant gas rather than humidifying the fuel gas has been emphasized.

  As a conventional automobile fuel cell system for humidifying oxidant gas, for example, Patent Document 2 supplies dry unused oxidant gas to one space of a humidifier partitioned by a water vapor permeable membrane, A technique is disclosed in which exhausted oxidant gas (off-gas) after being used is supplied to the space of the water to move moisture from the off-gas to the oxidant gas via a water vapor permeable membrane.

  However, in the above technique, since the moisture is moved by contacting the gas from both sides through the substantially planar water vapor permeable membrane, the contact area is small, and the moisture is moved with respect to the continuously supplied oxidant gas. There was a problem that the humidification efficiency was not sufficient in time.

  For such a problem, for example, Patent Documents 3 to 6 describe that after filling a hollow fiber membrane in a humidifier, an unused oxidant gas is circulated inside the hollow of the hollow fiber membrane, and after use. A technique is disclosed in which off-gas is circulated so as to be in contact with the outer wall of the hollow fiber membrane and moisture is transferred through the hollow fiber membrane. According to these techniques, since a large number of fine hollow fiber membranes are filled in the humidifier, the contact area for performing moisture movement is remarkably increased, compared with the technique described in Patent Document 1. Humidification efficiency is improved.

  However, since the hollow fiber membrane swells due to moisture absorption during the movement of moisture, when filling the humidifier, it is necessary to provide a gap between the hollow fiber membranes in advance in consideration of dimensional changes. It cannot be packed closely. In this way, there is a gap between the hollow fiber membranes, and the hollow fiber membranes can be elastically deformed. Therefore, when off-gas is introduced into the humidifier, the off-gas is introduced into the hollow fiber at the introduction portion where the gas flow rate is the highest. The film is pushed away, and a gap is formed. Since the off gas flows as a bypass path through the gap, there is a problem that the humidification efficiency is lowered because the gas cannot be uniformly circulated in the humidifier.

  With respect to such a problem, the technique described in Patent Document 4 manufactures a number of hollow fiber membranes that are bundled and fixed together with a rigid rod, and fills the humidifier with the hollow fiber membranes. The movement of is suppressed. Further, in the techniques described in Patent Documents 5 and 6, by providing a partition plate in the humidifier, an off-gas flow path is guided, and the bias of the hollow fiber membrane in a specific direction is suppressed.

Japanese Utility Model Publication No. 61-3671 JP-A-6-132038 Japanese Patent Application No. 2002-147802 Japanese Patent Application No. 2004-331287 Japanese Patent Application No. 2005-40675 Japanese Patent Application No. 2007-323982

  However, in the technique described in Patent Document 4, it is necessary to manufacture a large number of hollow fiber membranes bundled together with a rigid rod, which is not preferable because the number of steps increases. In addition, in the techniques described in Patent Documents 5 and 6, although the movement of the hollow fiber membrane can be suppressed as compared with the conventional technique, it is difficult to suppress even the deviation in the region partitioned by the partition plate, In addition, because the gas needs to be circulated, the partition plate cannot be completely closed, and the bias in the opening cannot be suppressed.

  Therefore, the present invention has been made to solve the above-mentioned problems of the prior art, and of course, it is possible to sufficiently humidify the dry unused fuel cell gas supplied into the hollow fiber membrane. It is intended to provide a moisture exchange hollow fiber membrane module capable of suppressing the unevenness of the hollow fiber membrane filled in the humidifier and uniformly distributing the wet off-gas after use of the fuel cell in the humidifier. It is aimed.

  The moisture exchange hollow fiber membrane module of the present invention includes a cylindrical case, a plurality of hollow fiber membranes filled in the space extending in the cylindrical case in the axial direction, and a plurality of hollow fibers at both ends of the cylindrical case. A sealing portion that fixes the thread membrane and seals the space; an introduction port provided on one side surface of the cylindrical case; a discharge port provided on an opposite surface of the side surface provided with the introduction port; and a hollow fiber A first fluid path from one end side of the membrane to the other end side through the hollow interior of the hollow fiber membrane, and a second fluid path from the introduction port to the discharge port in the space and outside the hollow fiber membrane A fluid path, a plurality of porous members extending in the axial direction in the space and having a surface crossing the second fluid path, and extending in the axial direction in the space, contacting and supporting the porous member And a support member having higher rigidity than the porous member.

  In the moisture exchange hollow fiber membrane module having the above configuration, for example, dry unused gas (oxidant gas or fuel gas) is circulated in the first fluid path passing through the inside of the hollow fiber membrane, and the outside of the hollow fiber membrane. A plurality of porous members are arranged in a space filled with a hollow fiber membrane when, for example, wet, off-use off-gas is circulated through the second fluid path passing through the gas to move the moisture of the off-gas to unused gas. Since the support member that contacts and supports the porous member is disposed, the hollow fiber membrane is restrained by the porous member supported by the support member. In particular, since the porous member has a surface that crosses the second fluid path, the movement of the hollow fiber membrane is suppressed with respect to the gas in the second fluid path. Thereby, since the clearance gap between a hollow fiber membrane and a cylindrical case is not formed, an off gas can distribute | circulate the inside of a hollow fiber membrane module uniformly, and can perform a water exchange efficiently.

  The support member is formed in a rod shape, and the plurality of porous members are formed in a cylindrical shape, and surround at least a part of the plurality of hollow fiber membranes in a cross-sectional view of a plane orthogonal to the axial direction. Of these, at least one porous member preferably surrounds the support member in cross-sectional view. Since the porous member surrounds the hollow fiber membrane in a cylindrical shape, the movement of the hollow fiber membrane is suppressed in that region. Furthermore, since the porous member also surrounds the support member, the movement of the porous member is suppressed more firmly by suppressing the movement of the porous member.

  When the porous member is cylindrical as described above, it is preferable that at least one of the support members is disposed upstream of the second fluid path from all the hollow fiber membranes. Since the upstream side of the second fluid path is the gas inlet side, the gas flow rate is high and the hollow fiber membrane is most likely to be biased. Therefore, a support member is provided in front of the hollow fiber membrane on the upstream side. If so, the fixing of the porous member by the support member becomes stronger, and as a result, all the hollow fiber membranes are supported and supported by the strongly fixed porous member, so that the movement is suppressed more firmly.

  On the other hand, when the porous member is not closed in a cylindrical shape and forms a flat surface (or a curved surface that is substantially flat), the support member is formed in a rod shape, and the plurality of porous members are each of two or more of the porous members. It is preferable that the support member is fixed along the side. According to such an aspect, since the two or more sides of the substantially planar porous member are fixed by the support member, the porous member is not deformed / moved even by gas pressure, and the porous member is made of a hollow fiber membrane. Restrain the movement.

  At least one of the supporting members is preferably formed integrally with the case. According to such an aspect, since the support member is integrated with the case, the rigidity is further improved, the deformation / movement of the porous member is surely suppressed, and the movement of the hollow fiber membrane is more firmly suppressed.

  In the dry state of the hollow fiber membrane, there are voids formed between the hollow fiber membranes and between the hollow fiber membrane and the porous member. It is preferable to reduce the part. According to such an aspect, the hollow fiber membrane and the porous member can be brought into contact with each other during operation of the moisture exchange hollow fiber membrane module, and the formation of a gap along the case is reliably suppressed.

  It is preferable that at least one end of the porous member for restraining the hollow fiber membrane is fixed by a seal portion. According to such an aspect, since the movement of the porous member is suppressed even if a force is applied during the flow of gas, damage to the hollow fiber membrane due to friction between the porous member and the hollow fiber membrane is suppressed.

  According to the present invention, since the hollow fiber membrane filled in the module is held and restrained between the porous member and the cylindrical case, the bias of the hollow fiber membrane due to the off-gas flow is suppressed, Can be distributed uniformly.

It is a see-through | perspective perspective view which shows the hollow fiber membrane module for water exchange. It is a sectional side view which shows the hollow fiber membrane module for water exchange of FIG. It is a sectional side view which shows the bias | inclination of the hollow fiber membrane in the conventional hollow fiber membrane module for water exchange. It is a schematic cross section which shows arrangement | positioning of the porous member in the hollow fiber membrane module for water exchange which concerns on embodiment of this invention, (a) is side sectional drawing, (b) is the sectional view on the AA line in (a). It is. It is a schematic cross section which shows arrangement | positioning of the porous member in the hollow fiber membrane module for water exchange of this invention. It is a schematic cross section which shows arrangement | positioning of the porous member in the hollow fiber membrane module for water exchange of this invention. It is a schematic cross section which shows arrangement | positioning of the porous member in the hollow fiber membrane module for water exchange of this invention. It is a top view which shows the example of the porous member of this invention. It is a schematic diagram which shows the example of joining of the porous member and support member of this invention.

  Embodiments of the present invention will be described below with reference to the drawings. First, prior to the description of the embodiment, a general configuration of a moisture exchange hollow fiber membrane module to which the present invention can be applied will be described with reference to FIGS. As shown in FIGS. 1 and 2, the moisture exchange hollow fiber membrane module M has a cylindrical case 10, and a space in the cylindrical case 10 (hereinafter may be abbreviated as a filling space) includes: A plurality of hollow fiber membranes 11 are filled in parallel to the axial direction of the cylindrical case 10 (direction in which the cylindrical case extends). Since the plurality of hollow fiber membranes 11 expand upon moisture absorption, the hollow fiber membranes 11 are filled through a predetermined interval in order to absorb the dimensional change.

  Both ends of the hollow fiber membrane 11 are fixed to the cylindrical case 10 by seal portions 14. In FIG. 1, the hollow fiber membrane 11 is partially omitted, but the hollow fiber membrane 11 extends between the seal portions 14 at both ends. The seal portion 14 is formed by embedding the outside of the hollow fiber membrane 11 in the filling space with a synthetic resin or the like, and seals only the filling space from the outside. Therefore, the hollow interior of the hollow fiber membrane 11 is not sealed, and both ends of the hollow fiber membrane 11 communicate with the outside. In the present embodiment, a path from the one end side (arrow 20) of the hollow fiber membrane 11 to the other end side (arrow 21) via the hollow interior of the hollow fiber membrane is defined as a first fluid path.

  A gas introduction port 12 is provided on one side surface (for example, the bottom surface in the figure) of the cylindrical case 10, and is on the downstream side of the introduction port 12 and on the opposite surface (for example, the top surface in the drawing). Is provided with a gas outlet 13. In the present embodiment, a path from the inlet 12 (arrow 22) in the filling space to the outlet 13 (arrow 23) via the outside of the hollow fiber membrane 11 is defined as a second fluid path.

  In the moisture exchange hollow fiber membrane module M described above, for example, a dry unused gas 20 of the fuel cell is introduced into the first fluid path, and an off gas 22 that is an exhaust gas after the gas is used in the fuel cell is used. Is introduced into the second fluid path, the dry unused gas 20 passes through the hollow fiber membrane 11, and the wet off-gas 22 after use passes outside the hollow fiber membrane 11 in the filling space. The hollow fiber membrane 11 prevents gas exchange between the inside and the outside, but can move only moisture through the fine holes present on both sides thereof, so that moisture is transferred from the high wet side to the low wet side. In this way, in each of the dry unused gas 20 introduced into the first fluid path and the second fluid path and the wet off-gas 22 after use, moisture moves and the humidified unused gas 21 is used. And it is discharged as off-gas 23 after use with reduced humidity.

  FIG. 3 is a diagram for explaining problems in a conventional moisture exchange hollow fiber membrane module. As described above, the hollow fiber membrane 11 is fixed in the filling space with a predetermined interval in the dry state in order to change the size by being wet. Further, the hollow fiber membrane 11 has a property of elastically deforming. Therefore, as shown in FIG. 3, when the off gas 22 is introduced from the introduction port 12, the pressure increases on the introduction port 12 side where the gas flow velocity is the largest, and the off gas 22 pushes the hollow fiber membrane 11 and deforms to form a tubular shape. A gap is generated along the bottom surface of the case 10. The off-gas moves to the downstream side (right side in the drawing) via this gap as shown by the arrow 24, and then flows toward the discharge port 13 and is discharged. As described above, the off-gas does not pass through the voids of the hollow fiber membrane 11 on the upstream side (left side in the figure), and moisture movement is performed only on the downstream side, so that the utilization rate and humidification efficiency of the hollow fiber membrane 11 are low. There was a problem.

First Embodiment FIG. 4 is a view showing a first embodiment of a moisture exchange hollow fiber membrane module of the present invention that can solve the above-mentioned conventional problems. 4A is a cross-sectional view cut in a direction parallel to the first fluid path flowing in the hollow fiber membrane 11, and FIG. 4B is a cross-sectional view cut in a direction orthogonal to the first fluid path. In the moisture exchange hollow fiber membrane module of the first embodiment shown in FIG. 4, the components other than the porous members 30a to 30c are the same as those in FIGS. The configuration, operation, and effect unique to the first embodiment will be described. The same applies to the following embodiments.

  As shown in FIGS. 4A and 4B, a plurality of cylindrical porous members 30a to 30c are provided in the filling space in parallel with the axial direction of the cylindrical case 10, and both ends thereof. Is fixed by being embedded in the seal portion 14. Further, on the most upstream side of the second fluid path of the hollow fiber membrane 11, a rod-like support member 40 is provided in parallel with the axial direction of the cylindrical case 10, and both ends thereof are embedded in the seal portion 14. Is fixed. The porous member 30a surrounds a part of the hollow fiber membrane and the support member 40, the porous member 30b surrounds the porous member 30a and a part of the hollow fiber membrane, and the porous member 30c includes the porous member 30 and a part of the hollow fiber membrane. Surrounds the hollow fiber membrane.

  The porous members 30a to 30c have an opening through which an off gas can sufficiently flow, have a rigidity that does not easily deform even when subjected to a gas pressure of the off gas, and have a corrosion resistance that can withstand long-term use. Consists of materials. The porous members 30a to 30c may be made of, for example, a mesh made of a metal such as stainless steel or plastic, and may be a plate-like member having a large number of openings formed therein.

  The support member 40 is configured to have rigidity higher than at least the porous member 40 described above, and is formed of a material having corrosion resistance that can withstand long-term use, like the porous member. For example, a metal such as stainless steel or plastic can be selected and formed into a solid bar shape.

  The method for forming the seal portion 14 in the present invention is not particularly limited, and any fixing means can be used. In the present embodiment, the filling space is filled with the hollow fiber membrane 11, the support member 40, and the porous members 30a to 30c in a state where the end portion of the cylindrical case 10 is erected, and the lower end portion is immersed and fixed in a resin. Subsequently, potting is employed in which the top and bottom are reversed and the other end is similarly immersed and fixed in resin. When potting, the soaked resin seals the inside and outside of the hollow fiber membrane 11, but since the distance between the hollow fiber membranes 11 is smaller than the diameter of the hollow fiber membrane 11, the resin is soaked by capillary action. The height is different and the inside is sealed shallower than the outside of the hollow fiber membrane 11. For this reason, by cutting and removing this portion, the inside of the hollow fiber membrane 11 can be communicated with the outside of the module, the resin can remain only outside the hollow fiber membrane 11, and the filling space can be sealed.

  In this embodiment, the expansion coefficient due to the wetness of the hollow fiber membrane 11 is grasped in advance. In order to suppress the movement of the hollow fiber membranes 11 when the expansion coefficient reaches the maximum, the hollow fiber membranes 11 and between the hollow fiber membranes 11 and the porous members 30a to 30c come into contact with each other so that there is no gap. Each is arranged so as to be filled with high density or with a reduced gap. On the other hand, in the dry state, the hollow fiber membrane 11 and the porous members 30a to 30c are disposed with a void (gap) therebetween.

  As the hollow fiber membrane 11 in the present invention, a known hollow fiber membrane can be selected. Specifically, polymers such as phenol sulfonic acid, polystyrene sulfonic acid, polytrifluorostyrene sulfonic acid, perfluorocarbon sulfonic acid, etc. Examples include an ion exchange membrane and a hollow fiber membrane such as a polymer resin or ceramic.

  According to the present embodiment, when the off-gas is introduced into the filling space from the inlet 12, the hollow fiber membrane 11 in the vicinity of the inlet 12 receives the gas pressure and is fixed in contact with the support member 40. Since the porous member 30a most restricts the hollow fiber membrane 11 on the inlet side, the movement of the hollow fiber membrane 11 in the region between the case surface on the inlet 12 side and the porous member 30a is suppressed. In addition, since the porous members 30b and 30c further restrain the hollow fiber membrane 11 on the outlet side, the hollow fiber membrane 11 in the region outside the porous member 30a and inside the porous member 30b, and the porous member 30b The movement of the hollow fiber membrane 11 in the outer region of the porous member 30c can also be suppressed. Thereby, since it is suppressed that a clearance gap produces along the cylindrical case 10, off gas distribute | circulates uniformly toward the downstream from the upstream in the filling space. Thereby, the utilization factor and humidification efficiency of the hollow fiber membrane 11 are improved.

  In particular, in this embodiment, since the hollow fiber membrane 11 and the porous members 30a to 30c are arranged with a predetermined gap in consideration of the expansion coefficient of the hollow fiber membrane 11 in advance, the moisture exchange hollow fiber membrane module During operation, the hollow fiber membrane 11 and the porous members 30a to 30c can be brought into contact with each other, and the formation of a gap along the cylindrical case 10 is reliably suppressed.

Second Embodiment FIG. 5 is a moisture exchange hollow fiber membrane module according to a second embodiment of the present invention, and is orthogonal to the first fluid path flowing in the hollow fiber membrane 11 as in FIG. 4B. It is sectional drawing cut | disconnected by direction. As shown in FIG. 5, a cylindrical porous member 31 whose interior is divided into a plurality of regions is provided in the filling space in parallel with the axial direction of the cylindrical case 10, and both ends thereof are sealed. It is fixed by being embedded in the part 14. Further, on the most upstream side of the second fluid path of the hollow fiber membrane 11, a rod-like support member 40 is provided in parallel with the axial direction of the cylindrical case 10, and both ends thereof are embedded in the seal portion 14. Is fixed. The porous member 31 surrounds the hollow fiber membrane 11 and the support member 40. The porous member 31 is divided into three regions by another porous member connected by means such as stitching and welding, and a part of the hollow fiber membrane is located in the most upstream region of the gas. 11 and the support member 40, and the remaining two regions on the downstream side surround the remaining hollow fiber membrane 11.

  In the present embodiment, the cylindrical porous member 31 can be regarded as a shape in which a plurality of cylindrical porous members are joined. Therefore, as in the first embodiment, even when the hollow fiber membrane 11 in the vicinity of the introduction port 12 receives gas pressure when off-gas is introduced into the filling space from the introduction port 12, the support member 40 in the porous member 31. Since the upstream region that is fixed in contact with the outermost portion restrains the hollow fiber membrane 11 on the introduction port side, the hollow fiber membrane 11 in the region between the case surface on the introduction port 12 side and the porous member 31. Since the remaining downstream region of the porous member 31 further restrains the hollow fiber membrane 11 on the discharge port side, the movement of the downstream hollow fiber membrane 11 can also be suppressed. . Thereby, since it is suppressed that a clearance gap produces along the cylindrical case 10, off gas distribute | circulates uniformly toward the downstream from the upstream in the filling space. Thereby, the utilization factor and humidification efficiency of the hollow fiber membrane 11 are improved.

Third Embodiment FIG. 6 is a moisture exchange hollow fiber membrane module according to a third embodiment of the present invention, and is a cross-sectional view cut in a direction orthogonal to the first fluid path flowing through the hollow fiber membrane 11. . As shown in FIG. 6, a plurality of cylindrical porous members 32 a to 32 c are provided in the filling space in parallel with the axial direction of the cylindrical case 10, and both end portions thereof are embedded in the seal portion 14. Is fixed. Also, rod-like support members 41 a to 41 c are provided in the filling space and inside the hollow fiber membrane bundle 11 in parallel with the axial direction of the cylindrical case 10, and both end portions thereof are connected to the seal portion 14. It is fixed by being buried.

  A support member 41a is fixed to the uppermost stream side of the second fluid path of the hollow fiber membrane 11 so as to contact and surround the support member 41a and to surround the uppermost stream side hollow fiber membrane 11. Is provided with a porous member 32a. A support member 41b is fixed downstream of the porous member 32a, and the porous member 32b is provided so as to contact and surround the support member 41b and to surround a part of the hollow fiber membrane 11. Yes. Further, a support member 41c is fixed on the downstream side of the porous member 32b. The porous member 32c is provided so as to contact and surround the support member 41c and to surround a part of the hollow fiber membrane 11. It has been.

  In this embodiment, even when the hollow fiber membrane 11 in the vicinity of the introduction port 12 is subjected to gas pressure when off-gas is introduced into the filling space from the introduction port 12, the porous member is fixed in contact with the support member 41a. Since the member 32a restrains the hollow fiber membrane 11 closest to the introduction port, the movement of the hollow fiber membrane 11 in the region between the case surface on the introduction port 12 side and the porous member 32a is suppressed. In addition, since the porous members 32b and 32c fixed in contact with the support members 41b and 41c further restrain the hollow fiber membrane 11 on the discharge port side, the hollow fiber membrane 11 in the region inside the porous member 32b. And the movement of the hollow fiber membrane 11 in the inner region of the porous member 32c can also be suppressed. Thereby, since it is suppressed that a clearance gap produces along the cylindrical case 10, off gas distribute | circulates uniformly toward the downstream from the upstream in the filling space. Thereby, the utilization factor and humidification efficiency of the hollow fiber membrane 11 are improved.

Fourth Embodiment FIG. 7 is a moisture exchange hollow fiber membrane module according to a fourth embodiment of the present invention, and is a cross-sectional view cut in a direction perpendicular to the first fluid path flowing through the hollow fiber membrane 11. . As shown in FIG. 7, a plurality of substantially planar porous members 33 a to 33 d are provided in the filling space in parallel with the axial direction of the cylindrical case 10, and both end portions thereof are embedded in the seal portion 14. Has been fixed. Further, rod-like support members 42 a to 42 d are provided in the filling space and inside the hollow fiber membrane bundle 11 in parallel with the axial direction of the cylindrical case 10, and both end portions thereof are connected to the seal portion 14. It is fixed by being buried. The porous members 33a to 33d are fixed by connecting support members 42a to 42d to both ends (both sides). In the present embodiment, the support members 42 a to 42 d are not only fixed by the seal portion 14 but also integrally formed on the side surface of the cylindrical case 10.

  On the uppermost stream side of the second fluid path of the hollow fiber membrane 11, a porous member 33a is fixed to the cylindrical case 10 via support members 42a at both ends, and on the downstream side, a support member 42b is similarly formed. The porous members 33b to 33d are fixed to the cylindrical case 10 through ~ 42d.

  In this embodiment, even if the hollow fiber membrane 11 in the vicinity of the introduction port 12 is subjected to gas pressure when off-gas is introduced into the filling space from the introduction port 12, the porous members 33 a to 33 d are connected to the cylindrical case 10. Since it is firmly fixed to the cylindrical case 10 via the integrated support members 42a to 42d, movement of the hollow fiber membrane 11 sandwiched between the porous members is suppressed. Thereby, since it is suppressed that a clearance gap produces along the cylindrical case 10, off gas distribute | circulates uniformly toward the downstream from the upstream in the filling space. Thereby, the utilization factor and humidification efficiency of the hollow fiber membrane 11 are improved.

  In the present embodiment, it is sufficient that the porous member 33 has at least two sides fixed by a rod-like support member 42. For example, it is preferable that two opposing sides are fixed as shown in FIG. It is more preferable that the four sides are fixed as shown in FIG. Further, as a fixing method of the porous member 33 and the support member 42, for example, as shown in FIG. 9A, the contact region of the porous member 33 and the support member 42 is welded, or as shown in FIG. 9B. Alternatively, the support member 42 may be formed with a recess and a penetrating portion, and the porous member 33 may be passed through the penetrating portion, and a fixing means 43 such as a pin or a screw may be inserted into the recess and fixed.

In the above description, an example has been described in which a dry unused gas is allowed to flow through the first fluid path and a wet off-gas after use is allowed to flow into the second fluid path. However, the present invention is limited only to this aspect. Instead of this, it is possible to exchange moisture by flowing a wet off-gas after use in the first fluid path and flowing a dry unused gas in the second fluid path.

  Furthermore, in the above description, the case where the cross-section of the cylindrical case 10 is rectangular has been described as an example. However, the moisture exchange hollow fiber membrane module of the present invention is not limited to a rectangle, for example, the cross-section is polygonal. It can also be cylindrical.

  According to the present invention, the moisture of the off-gas discharged from the fuel cell can be reused for humidification of the unused oxidant gas, and an appropriate humidification amount of the fuel cell can be obtained by increasing the humidification efficiency in moisture exchange. Therefore, it is extremely promising when applied to an on-vehicle fuel cell system that requires strict and stable operation.

M ... Hollow fiber membrane module for moisture exchange,
10 ... cylindrical case,
11 ... Hollow fiber membrane,
12 ... Gas inlet,
13 ... Gas outlet,
14 ... seal part,
20 ... Unused gas (low wetness),
21 ... Unused gas (after water exchange),
22: Off-gas after use (high humidity),
23 ... Off-gas after use (after water exchange),
30-33 ... porous member,
40-42 ... support member,
43 ... Fixing means

Claims (7)

A cylindrical case,
A plurality of hollow fiber membranes filled in the space in the cylindrical case extending in the axial direction;
A seal portion that fixes the plurality of hollow fiber membranes at both ends of the cylindrical case and seals the space;
An inlet provided on one side of the cylindrical case;
A discharge port provided on the opposite surface of the side surface provided with the introduction port;
A first fluid path from one end side of the hollow fiber membrane to the other end side through the hollow interior of the hollow fiber membrane;
A second fluid path from the introduction port into the space and through the outside of the hollow fiber membrane to the discharge port;
A plurality of porous members having a surface extending in the axial direction in the space and crossing the second fluid path;
A moisture exchange hollow fiber membrane module comprising: a support member extending in the axial direction in the space, contacting and supporting the porous member, and having higher rigidity than the porous member. . The support member is formed in a rod shape,
The plurality of porous members are formed in a cylindrical shape, and surround at least a part of the plurality of hollow fiber membranes in a cross-sectional view of a surface orthogonal to the axial direction.
2. The moisture exchange hollow fiber membrane module according to claim 1, wherein at least one of the plurality of porous members surrounds the support member in the cross-sectional view.   3. The moisture exchange hollow fiber membrane module according to claim 1, wherein at least one of the support members is disposed upstream of all the hollow fiber membranes in the second fluid path. 4. The support member is formed in a rod shape,
The hollow fiber membrane module for water exchange according to claim 1, wherein the support member is fixed along each of two or more sides of the plurality of porous members.   5. The moisture exchange hollow fiber membrane module according to claim 1, wherein at least one of the support members is formed integrally with the case.   In the dry state of the hollow fiber membrane, there are voids formed between the hollow fiber membranes and between the hollow fiber membrane and the porous member, and in the swollen state of the hollow fiber membrane, they are in contact with each other. The hollow part for moisture exchange according to any one of claims 1 to 5, wherein the voids are reduced. The hollow fiber membrane module for moisture exchange according to any one of claims 1 to 6, wherein at least one end of the porous member is fixed by the seal portion.

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