Hollow fiber membrane module and dehumidifying and humidifying device

Abstract

The present application provides a hollow fiber membrane module and a dehumidification and humidification device capable of improving the contribution rate of the membrane separation effect of the hollow fiber membrane and improving the dehumidification and humidification performance. The present application is characterized in that a double tube portion (120) is provided in an outer shell (100), and a communication portion (121) and an outlet portion (122) are provided, the double tube portion (120) forms an annular space (K) at a position radially outward of the annular gap (S) at one end side, the communication portion (121) communicates the one end side of the annular gap (S) and the annular space (K), the outlet portion (122) communicates the annular space (K) and the outside of the outer shell (100), and an inner shell (200) is provided with a hollow portion open to the other end side, and a plurality of windows (221) are provided to communicate the hollow portion and the annular gap (S).

Description

Technical Field

[0001] This invention relates to hollow fiber membrane modules and dehumidification and humidification devices. Background Technology

[0002] For hollow fiber membrane modules used in humidification devices for fuel cells, there are requirements for improved humidification performance, suppression of pressure loss, and miniaturization. To achieve these, it is necessary to increase the contribution of the hollow fiber membrane housed within the housing to membrane separation. Therefore, techniques are known to address these requirements by designing the housing of the hollow fiber membrane module as a double-layered structure. Regarding such existing hollow fiber membrane modules, see [reference needed]. Figure 3 Please provide an explanation. Figure 3 This is a schematic cross-sectional view of an existing hollow fiber membrane module.

[0003] The hollow fiber membrane assembly 500 shown in the figure includes a cylindrical outer shell 510, an inner shell 520 disposed inside the outer shell 510, and a plurality of hollow fiber membranes 530 disposed in an annular gap between the outer shell 510 and the inner shell 520. Furthermore, the hollow fiber membrane assembly 500 includes a pair of sealing and fixing portions 541, 542 and a pair of buffer portions 551, 552. The sealing and fixing portions 541, 542 respectively seal the annular gap at one end of the outer shell 510 and the other end of the inner shell 520, while keeping the hollow interiors of each hollow fiber membrane 530 open, and fix the plurality of hollow fiber membranes 530 to the outer shell 510 and the inner shell 520.

[0004] Furthermore, in the outer casing 510, at least one location in the circumferential direction is provided with an outlet portion 511 that connects the aforementioned annular gap to the outer side of the outer casing 510. It should be noted that in the portion where the outlet portion 511 is not provided, in order to avoid contact with the outer peripheral surface of the bundle composed of multiple hollow fiber membranes 530, a portion 512 of the inner peripheral surface of the outer casing 510 has a larger inner diameter than other portions.

[0005] In addition, a partition wall 521 is provided inside the inner shell 520, and a plurality of windows 522 are provided on the other end side of the partition wall 521 to connect the hollow part inside the inner shell 520 with the aforementioned annular gap.

[0006] For the hollow fiber membrane assembly 500 configured as described above, humidifying gas is supplied to the hollow portion inside the inner housing 520, and dry gas is supplied to the hollow interior of each hollow fiber membrane 530 from the sealing and fixing portion 541 side. Thus, as shown by the solid arrows in the figure, the humidifying gas enters the annular gap through the multiple windows 522, passes through the outside of the hollow fiber membrane 530, and flows from the outlet 511 to the outside of the outer housing 510. Meanwhile, the dry gas flows from the sealing and fixing portion 541 at one end towards the sealing and fixing portion 542 at the other end, passing through the interior of the hollow fiber membrane 530. Therefore, through membrane separation based on the hollow fiber membrane 530, moisture in the humidifying gas moves to the dry gas side, thereby humidifying the dry gas.

[0007] In typical hollow fiber membrane modules, multiple hollow fiber membranes are housed within a single cylindrical shell, which has an inlet and outlet for humidified gas. Therefore, hollow fiber membranes positioned near the center of the shell tend to contribute little to membrane separation. In this regard, in the aforementioned... Figure 3 In the case of the existing hollow fiber membrane module 500 shown, the collective hollow fiber membranes 530 can contribute to the membrane separation function, thus meeting the above requirements.

[0008] However, even in the case of the hollow fiber membrane assembly 500 described above, the flow of humid gas passing through the shortest distance from the window 522 toward the outlet 511 tends to become the mainstream. Therefore, it is evident that in the regions of the multiple hollow fiber membranes 530 far from the outlet 511 (near X1 in the figure), and in the region on one end and radially inward (near X2 in the figure), it is difficult to facilitate membrane separation. Thus, there is room for improvement.

[0009] Existing technical documents

[0010] Patent documents

[0011] Patent Document 1: Japanese Patent Application Publication No. 2002-147802

[0012] Patent Document 2: Japanese Patent Application Publication No. 2005-265196 Summary of the Invention

[0013] The technical problem that the invention aims to solve

[0014] The purpose of this invention is to provide a hollow fiber membrane module and a dehumidification and humidification device that can improve the contribution rate of hollow fiber membrane to membrane separation and improve dehumidification and humidification performance.

[0015] Solutions for solving technical problems

[0016] That is, the hollow fiber membrane module of the present invention includes:

[0017] Cylindrical outer shell;

[0018] An inner housing, disposed inside the outer housing;

[0019] Multiple hollow fiber membranes are disposed in the annular gap between the outer shell and the inner shell; and

[0020] A pair of sealing and fixing parts, located at one end and the other end of the outer shell and inner shell, respectively seal the annular gap while keeping the hollow interior of each hollow fiber membrane open, and fix the plurality of hollow fiber membranes to the outer shell and inner shell.

[0021] The hollow fiber membrane module is characterized in that...

[0022] The outer casing has a double-tube section with a connecting portion and an outlet portion. The double-tube section forms an annular space at one end, radially outward from the annular gap. The connecting portion connects the annular gap and the one end of the annular space. The outlet portion connects the annular space and the outer side of the outer casing.

[0023] The inner housing has a hollow portion that opens to the other end and has a plurality of windows that connect the hollow portion and the annular gap.

[0024] According to the present invention, fluid flowing from the hollow portion of the inner shell through the window into the annular gap flows from the connecting portion toward the annular space and then flows from the outlet to the outside of the outer shell. This suppresses the amount of fluid flowing directly from the window to the outlet. Therefore, the contribution of the hollow fiber membrane to membrane separation can be increased.

[0025] Alternatively, the connecting portion may be arranged throughout the entire circumference.

[0026] This allows for a further increase in the contribution of hollow fiber membranes to membrane separation.

[0027] Alternatively, the outlet may be located at at least one location in the circumferential direction.

[0028] Alternatively, the inner housing may be provided with a widening portion, the width of which increases from one end to the other end in a direction perpendicular to the direction from one end to the other end, and the plurality of windows are provided in the widening portion.

[0029] By adopting such a structure, it is possible to facilitate the convection between the fluid outside the hollow fiber membrane and the fluid inside the hollow fiber membrane near the window.

[0030] The dehumidification and humidification device of the present invention is characterized in that it includes:

[0031] The hollow fiber membrane module mentioned above;

[0032] A humidifying gas supply device supplies humidifying gas relative to the hollow portion; and

[0033] A dry gas supply device supplies dry gas with a lower humidity than the humidifying gas from the closed fixing part on one end to the hollow interior of each of the plurality of hollow fiber membranes.

[0034] It should be noted that the above structures can be used in combination as much as possible.

[0035] Invention Effects

[0036] As explained above, according to the present invention, it is possible to increase the contribution rate of hollow fiber membrane to membrane separation and improve dehumidification and humidification performance. Attached Figure Description

[0037] Figure 1 This is a top view of a hollow fiber membrane assembly according to an embodiment of the present invention.

[0038] Figure 2 This is a schematic structural diagram of a dehumidification and humidification device according to an embodiment of the present invention.

[0039] Figure 3 This is a schematic cross-sectional view of an existing hollow fiber membrane module. Detailed Implementation

[0040] Hereinafter, with reference to the accompanying drawings, exemplary embodiments are described to illustrate how to implement the invention. However, the dimensions, materials, shapes, and relative arrangements of the structural components described in these embodiments are not intended to limit the scope of the invention, unless otherwise specifically stated.

[0041] (Example)

[0042] Reference Figure 1 and Figure 2 The hollow fiber membrane module and dehumidification and humidification device of embodiments of the present invention will be described. Figure 1 This is a top view of a hollow fiber membrane assembly according to an embodiment of the present invention. Figure 2 This is a schematic structural diagram of a dehumidification and humidification device according to an embodiment of the present invention. It should be noted that... Figure 2 The hollow fiber membrane module is shown in a schematic cross-sectional view. The cross-sectional view of this hollow fiber membrane module is equivalent to... Figure 1 AA section view in the image.

[0043] <Dehumidifier and Humidifier>

[0044] The dehumidification and humidification device of this embodiment includes a hollow fiber membrane module 10, a humidifying gas supply device 20, and a drying gas supply device 30. The humidifying gas supply device 20 is configured to supply humidifying gas to the outside of the hollow fiber membrane 300 provided in the hollow fiber membrane module 10. The drying gas supply device 30 is configured to supply dry gas with a lower humidity than the humidifying gas to the hollow interior of each of the plurality of hollow fiber membranes 300. Thus, through membrane separation based on the hollow fiber membrane 300, moisture in the humidifying gas moves to the drying gas side. Therefore, the drying gas is humidified, and the humidifying gas is dehumidified, thus it can be used as both a humidification device and a dehumidification device. It should be noted that the dehumidification and humidification device of this embodiment can be suitably used as a humidification device for humidifying the dielectric membrane provided in a fuel cell. In this case, the humidified air generated in the fuel cell is utilized as the aforementioned humidifying gas. Furthermore, by supplying the humidified gas (air) to the electrolyte membrane provided in the fuel cell, the electrolyte membrane is maintained in a moist state. Here, as a raw material for the hollow fiber membrane 300, PPSU (polyphenylsulfone), which has the characteristic of permeating water through a capillary condensation mechanism based on pore size control, can be suitably used, for example. It should be noted that when adjusting the membrane-forming solution (the raw material for the hollow fiber membrane), a hydrophilic hollow fiber membrane can be obtained by spinning a membrane-forming solution in which PPSU and a hydrophilic polymer (polyvinylpyrrolidone) are added to the solvent. Alternatively, Nafion (registered trademark), a hydrophilic material with the characteristic of permeating water through dissolution and diffusion, can also be used. Such materials, due to their low solubility and high strength, are suitable for use in dehumidification and humidification devices.

[0045] Hollow fiber membrane modules

[0046] The hollow fiber membrane assembly 10 of this embodiment will be described in more detail. The hollow fiber membrane assembly 10 includes a cylindrical outer shell 100, an inner shell 200 disposed inside the outer shell 100, and a plurality of hollow fiber membranes 300 disposed in an annular gap S between the outer shell 100 and the inner shell 200. Furthermore, the hollow fiber membrane assembly 10 includes a pair of sealing and fixing portions 410, 420 and a pair of buffer portions 430, 440. The sealing and fixing portions 410, 420 are located at one end of the outer shell 100 and the inner shell 200 (…). Figure 2 (middle right side) and the other end side ( Figure 2The left side of the hollow fiber membrane assembly 410 and 420 serves to close the annular gaps S when the hollow interiors of each hollow fiber membrane 300 are open, and to fix the multiple hollow fiber membranes 300 to the outer shell 100 and the inner shell 200. These sealing and fixing portions 410 and 420 can be obtained by curing epoxy resin or other potting materials. In addition, a pair of buffer portions 430 and 440 are made of a highly flexible material such as silicon. By providing these buffer portions 430 and 440, the swaying of the hollow fiber membranes 300 near the sealing and fixing portions 410 and 420 can be suppressed, and damage to the hollow fiber membranes 300 near the boundaries with the sealing and fixing portions 410 and 420 can be suppressed. It should be noted that, for convenience, in the hollow fiber membrane assembly 10 below, the following will refer to... Figure 2 The right side is called the "one end side", and the left side is called the "other end side".

[0047] The outer casing 100 includes a cylindrical casing main body 110. In this embodiment, the casing main body 110 is composed of a generally cylindrical portion, but its shape is not limited to this; for example, it can adopt various shapes such as a prism shape. Additionally, a double tube portion 120 is provided in the outer casing 100, which forms an annular space K at one end, radially outward from the annular gap S. In this embodiment, the double tube portion 120 is composed of a cylindrical portion 120a and a connecting portion 120b. The outer diameter and inner diameter of the cylindrical portion 120a are larger than the outer diameter and inner diameter of the casing main body 110, and the connecting portion 120b connects the other end of the cylindrical portion 120a to the casing main body 110. Furthermore, the outer casing 100 is provided with a connecting portion 121 that connects the annular gap S and the annular space K at one end, and an outlet portion 122 that connects the annular space K and the outer side of the outer casing 100. In this embodiment, the connecting portion 121 is provided throughout the entire circumference. It should be noted that, from the viewpoint of increasing the contribution rate of the hollow fiber membrane 300 to the membrane separation effect, it is desirable to provide the connecting portion 121 throughout the entire circumference, but it is not necessary to provide it throughout the entire circumference; multiple portions can also be provided at intervals in the circumferential direction. In addition, the outlet portion 122 is provided at least at one location in the circumferential direction, and its number can be appropriately set according to the size of the hollow fiber membrane module 10 and the operating environment.

[0048] The housing 200 has a structure in which a partition wall 210 is provided inside a cylindrical component. This results in a structure where the inner housing 200 has a hollow portion opening to the other end. Furthermore, the inner housing 200 has a widening portion 220, the width of which increases from one end to the other in a direction perpendicular to the direction from one end to the other. In this embodiment, the inner and outer peripheral surfaces of the widening portion 220 are conical. However, the shape of the inner and outer peripheral surfaces of the widening portion 220 is not limited to conical surfaces; other shapes can be used as long as the width gradually increases in a direction perpendicular to the direction from one end to the other. For example, a curved surface or a pyramidal surface, formed by cutting a surface containing a central axis, can also be used.

[0049] Furthermore, in the inner shell 200, a plurality of windows 221 are provided in the widened portion 220, connecting the hollow portion and the annular gap S. It should be noted that, in the inner shell 200, at one end closer to the widened portion 220, the inner diameter and outer diameter are configured to be constant. That is, it is composed of a cylindrical portion.

[0050] For the hollow fiber membrane assembly 10 configured as described above, humidifying gas is supplied to the hollow portion of the inner shell 200 via the humidifying gas supply device 20. Additionally, dry gas is supplied from the sealing and fixing portion 410 at one end to the hollow interiors of each of the plurality of hollow fiber membranes 300 via the dry gas supply device 30. This will be explained in more detail.

[0051] Moisturizing gas is supplied to the hollow section from the moisturizing gas supply device 20. Figure 2 (Arrow A1) The humidified gas enters the annular gap S through multiple windows 221 (Arrow A2). The humidified gas entering the annular gap S passes through the outside of the hollow fiber membrane 300, flows from the connecting portion 121 to the annular space K (Arrow A3), and then flows from the outlet portion 122 to the outside of the outer casing 100. Meanwhile, dry gas is supplied from the sealing and fixing portion 410 on one end side to the hollow interior of each of the multiple hollow fiber membranes 300 via the dry gas supply device 30 (Arrow B1), and flows within each hollow fiber membrane 300 (Arrow B2). Afterwards, it is discharged from the sealing and fixing portion 420 on the other end side (Arrow B3). In the above process, through membrane separation based on the hollow fiber membrane 300, moisture in the humidified gas moves to the dry gas side, the dry gas is humidified, and the humidified gas is dehumidified.

[0052] <Advantages of the hollow fiber membrane module and dehumidification and humidification device in this embodiment>

[0053] According to this embodiment, humidified gas is configured to flow from multiple windows 221 provided in the inner housing 200 to the outlet portion 122 provided in the outer housing 100. Therefore, the collective structure of the multiple hollow fiber membranes 300 provided in the annular gap S between the inner housing 200 and the outer housing 100 can contribute to membrane separation. Furthermore, in this embodiment, fluid flowing from the hollow portion of the inner housing 200 through the windows 221 to the annular gap S flows from the connecting portion 121 to the annular space K and then flows from the outlet portion 122 to the outside of the outer housing 100. This suppresses the amount of fluid flowing directly from the windows 221 to the outlet portion 122. Therefore, the contribution rate of the hollow fiber membranes 300 to membrane separation can be increased.

[0054] Furthermore, in this embodiment, the connecting portion 121 is arranged throughout the entire circumference. This further enhances the contribution of the hollow fiber membrane 300 to membrane separation.

[0055] Furthermore, the inner housing 200 of this embodiment is provided with a widening portion 220, the width of which increases from one end to the other in a direction perpendicular to the direction from one end to the other, and a plurality of windows 221 are provided in the widening portion 220. Therefore, near the windows 221, fluid passing through the outside of the hollow fiber membrane 300 and fluid passing through the hollow interior of the hollow fiber membrane 300 can easily convection. As a result, membrane separation can be improved, and dehumidification and humidification performance can be improved.

[0056] (other)

[0057] In the above embodiments, a structure is shown in which a widening portion 220 is provided in the inner housing 200 and a plurality of windows 221 are provided in the widening portion 220. However, the present invention also includes a structure in which a widening portion is not provided in the inner housing, but a plurality of windows are provided in a portion with a constant width. For example, for the case described in the prior art Figure 3 The inner housing 520 with multiple windows 522 shown can also be applied to this application.

[0058] Explanation of reference numerals in the attached figures

[0059] 10 Hollow fiber membrane modules

[0060] 20 Humidifying gas supply device

[0061] 30 Drying gas supply device

[0062] 100 outer shell

[0063] 110 Main body of the shell

[0064] 120 Double-pipe section

[0065] 120a Cylindrical section

[0066] 120b Connector

[0067] 121 Connecting Part

[0068] 122 Export Department

[0069] 200 Inner shell

[0070] 210 partition wall

[0071] 220 Widening Section

[0072] Window 221

[0073] 300 Hollow Fiber Membrane

[0074] 410, 420 Enclosed fixing parts

[0075] 430, 440 buffer section

[0076] K-ring space

[0077] S-shaped gap

Claims

1. A hollow fiber membrane module, comprising: A cylindrical outer shell with a constant width between its outer and inner circumferential surfaces; An inner housing, disposed inside the outer housing; Multiple hollow fiber membranes are disposed in the annular gap between the outer shell and the inner shell; and A pair of sealing and fixing parts, located at one end and the other end of the outer shell and inner shell, respectively seal the annular gap while keeping the hollow interior of each hollow fiber membrane open, and fix the plurality of hollow fiber membranes to the outer shell and inner shell. The hollow fiber membrane module is characterized in that... The outer casing has a double-tube section, a connecting section, and an outlet section. The double-tube section forms an annular space at one end, radially outward from the annular gap. The connecting section connects the annular gap and the one end of the annular space. The outlet section connects the annular space and the outer side of the outer casing. The connecting section is located in the annular space at a circumferential position of the outer casing near the one end. The inner housing has a hollow portion that opens to the other end, and also has a plurality of windows that connect the hollow portion and the annular gap. The hollow portion includes a widened portion and a cylindrical portion. The widened portion increases in width from one end to the other end in a direction perpendicular to the direction from one end to the other end. The cylindrical portion in the inner housing is located closer to one end than the widened portion. Its inner and outer diameters in a direction perpendicular to the direction from one end to the other end are constant. The widened portion is provided with a plurality of windows that connect the hollow portion and the annular gap.

2. The hollow fiber membrane module according to claim 1, characterized in that, The connecting portion is arranged throughout the entire circumference.

3. The hollow fiber membrane module according to claim 1 or 2, characterized in that, The annular gap includes a portion whose width decreases from one end to the other end in a direction perpendicular to the direction from one end to the other end.

4. A dehumidification and humidification device, characterized in that, include: Hollow fiber membrane module as described in any one of claims 1 to 3; A humidifying gas supply device supplies humidifying gas relative to the hollow portion; and A dry gas supply device supplies dry gas with a lower humidity than the humidifying gas from the closed fixing part on one end to the hollow interior of each of the plurality of hollow fiber membranes.

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