Hollow fiber membrane module

Abstract

This hollow fiber membrane module has at least a plurality of hollow fiber membranes, a first potting part for bonding the hollow fiber membranes such that first ends thereof are opened, a first fluid inlet that is air-tightly connected to the openings of the first ends, a second potting part for bonding the hollow fiber membranes so that the second ends of the hollow fiber membranes are opened, and a first fluid outlet that is air-tightly connected to the openings of the second ends, wherein the filling ratio of the plurality of hollow fiber membranes for a cross-section of the first potting part and a cross-section of the second potting part in the longitudinal direction of the hollow fiber membranes is 5-40%, and the hollow fiber membrane module has an opening part where the hollow fiber membranes are exposed in the longitudinal direction of the hollow fiber membranes.

Description

Hollow fiber membrane module

[0001] The present invention relates to a hollow fiber membrane module, a dehumidifier / humidifier, and an air conditioner.

[0002] Hollow fiber membranes are widely used in medical applications, such as blood purifiers for patients with renal failure, and in water treatment applications, such as water purifiers. Furthermore, hollow fiber membranes with pores large enough to separate gases exhibit superior gas separation properties compared to other inorganic membranes, and can be used in environments requiring chemical and heat resistance. Gas separation targets using hollow fiber porous membranes are diverse, including the separation of water vapor and carbon dioxide from air and the separation of harmful components contained in factory exhaust gases.

[0003] Hollow fiber membranes that allow water vapor to pass through are increasingly being used for humidifying fuel gas to keep the electrolyte membranes built into fuel cell systems moist, and for dehumidifying spaces such as offices and homes. Ultrafiltration membranes, microfiltration membranes, and the like are commonly used as hollow fiber membranes, and a method of using a polysulfone-based resin, which has excellent strength stability under humidified conditions, has been proposed (see, for example, Patent Documents 1 and 2).

[0004] JP 2020-44523 JP 2011-67812

[0005] When a large flow rate of a gas to be treated or processed is passed through a hollow fiber membrane module to improve gas separation efficiency, an increase in pressure loss in the module can increase the load on the treatment equipment and reduce the efficiency of the entire device. For example, the hollow fiber membrane modules described in Patent Documents 1 and 2 perform dehumidification and humidification using high-pressure air compressed by a compressor. When such a hollow fiber membrane module is connected to an air conditioner or blower, the pressure loss generated within the hollow fiber membrane module can exceed the maximum static pressure of the blower, potentially preventing the blower from delivering air. Therefore, installing a conventional hollow fiber membrane module in an existing facility can sometimes require the installation of a high-power blower with a static pressure that exceeds the pressure loss within the module, making it difficult to actually install the module as an add-on to an existing air conditioner.

[0006] In order to solve the above-mentioned problems and achieve the object, the hollow fiber membrane module of the present invention is a hollow fiber membrane module having at least a plurality of hollow fiber membranes, a first potting portion that bonds the hollow fiber membranes together so that their first ends are open, a first fluid inlet airtightly connected to the opening of the first end, and a first fluid outlet airtightly connected to the opening of the second end, wherein the filling rates of the plurality of hollow fiber membranes with respect to the cross-sectional areas of the first potting portion and the second potting portion in the longitudinal direction of the hollow fiber membranes are 5% or more and 40% or less, and the hollow fiber membrane module has openings through which the hollow fiber membranes are exposed in the longitudinal direction of the hollow fiber membranes in the hollow fiber membrane module.

[0007] The hollow fiber membrane module obtained by the present invention can provide a hollow fiber membrane module that can efficiently transfer heat and substances even in a low static pressure environment.

[0008] FIG. 1 is a schematic diagram showing a hollow fiber membrane module according to embodiment 1 of the present invention. FIG. 2 is a schematic diagram showing a hollow fiber membrane module according to a modified example of embodiment 1 of the present invention. FIG. 3 is a schematic diagram showing a hollow fiber membrane module according to embodiment 2 of the present invention. FIG. 4 is a diagram showing a separation distance between hollow fiber membrane bundles in a hollow fiber membrane module according to embodiment 2 of the present invention. FIG. 5 is a schematic diagram showing a hollow fiber membrane module according to embodiment 3 of the present invention. FIG. 6 is a diagram showing a separation distance between hollow fiber membrane sheet layers in a hollow fiber membrane module according to embodiment 3 of the present invention. FIG. 7 is a schematic diagram showing a method for manufacturing a hollow fiber membrane module according to embodiment 1 of the present invention. FIG. 8 is a schematic diagram of an air conditioner. FIG. 9 is a schematic diagram explaining a method for measuring moisture permeability.

[0009] Preferred embodiments of the hollow fiber membrane module according to the present invention will be described in detail below with reference to the drawings as necessary, although the present invention is not limited to these embodiments.

[0010] <Hollow fiber membrane module> The hollow fiber membrane module of the present invention is a hollow fiber membrane module having at least a plurality of hollow fiber membranes, a first potting part bonding the hollow fiber membranes together so that their first ends are open, a first fluid inlet airtightly connected to the opening at the first end, a second potting part bonding the hollow fiber membranes together so that their second ends are open, and a first fluid outlet airtightly connected to the opening at the second end, wherein the filling rates of the plurality of hollow fiber membranes relative to the cross-sectional areas of the first potting part and the second potting part in the longitudinal direction of the hollow fiber membranes are from 5% to 40%, and the hollow fiber membrane module has openings through which the hollow fiber membranes are exposed in the longitudinal direction of the hollow fiber membranes.

[0011] (Embodiment 1) A hollow fiber membrane module according to Embodiment 1 of the present invention will be described. The hollow fiber membrane module according to Embodiment 1 is a hollow fiber membrane module in which a plurality of hollow fiber membranes are connected to a first potting and a second potting, spaced apart from one another. By arranging the hollow fiber membranes spaced apart from one another, it is possible to reduce the pressure loss of the second fluid flowing outside the hollow fiber membranes through openings where the hollow fiber membranes are exposed in the longitudinal direction of the hollow fiber membranes, thereby enabling efficient heat or mass transfer with the first fluid flowing inside the hollow fiber membranes.

[0012] To efficiently transfer substances through the hollow fiber membrane, it is preferable that the hollow fiber membrane has micropores. This allows permeable substance transfer according to the size of the micropores. Possible mass transfer mechanisms include capillary aggregation and diffusion due to concentration gradients.

[0013] FIG. 1 is a schematic diagram showing a configuration example of a hollow fiber membrane module according to a first embodiment of the present invention, including a perspective view (a), a side view (b), and a cross-sectional view (c) taken along line II' in (b). As shown in FIG. 1, in a hollow fiber membrane module 10 according to the first embodiment, the first ends of twelve hollow fiber membranes 1 are fixed to a module case 6 via a first potting 2 and the second ends thereof via a second potting 3 (not shown). Furthermore, as shown in FIG. 1(c), the twelve hollow fiber membranes 1 are fixed by the first potting 2 and the second potting 3, spaced apart so that their first and second ends are open. The module case 6 has a first fluid inlet 4 airtightly connected to the openings at the first ends of the hollow fiber membranes 1 and a first fluid outlet 5 airtightly connected to the openings at the second ends of the hollow fiber membranes 1. As a result, a first fluid flowing in through the first fluid inlet passes inside the hollow fiber membranes 1 and is discharged from the first fluid outlet 5. In the present invention, "airtightly connected" means a state in which the connection is made without leakage of fluid. The module case 6 is a rectangular prism having four openings 7 on its side, and the hollow fiber membranes 1 are exposed at the openings 7. The second fluid flows in through one of the four openings 7 and is discharged from another opening 7. At this time, heat or mass transfer occurs between the second fluid passing through the outside of the hollow fiber membranes and the first fluid flowing inside the hollow fiber membranes.

[0014] For the sake of simplicity, FIG. 1 illustrates a hollow fiber membrane module 10 including 12 hollow fiber membranes, but the number of hollow fiber membranes is not limited to 12.

[0015] The filling rate of the hollow fiber membranes 1 is 5% to 40% of the cross-sectional area of ​​each of the first potting section 2 and the second potting section 3. This range allows for reduced pressure loss even in low static pressure environments, enabling the formation of a module capable of heat or mass transfer between the first and second fluids. A filling rate of 5% to 30% is even more preferable. This range allows for the flow rate of the second fluid to be maintained without applying a high pressure load, and further reduces pressure loss. Therefore, by arranging multiple hollow fiber membrane modules in parallel, the amount of heat or mass transfer between the first and second fluids can be increased while reducing pressure loss. The filling rate of the hollow fiber membranes relative to the cross-sectional area of ​​each of the first and second potting sections in the present invention refers to the ratio of the sum of the cross-sectional areas of the hollow fiber membranes, based on the outer diameter, to the cross-sectional area of ​​the first and second potting sections cut perpendicular to the longitudinal direction of the hollow fiber membranes. The sum of the cross-sectional areas, based on the outer diameter, of the hollow fiber membranes can be measured using the following method.

[0016] First, five arbitrary hollow fiber membranes are extracted from the hollow fiber membrane module, and five cross sections are cut out from each. Images of the obtained hollow fiber membrane cross sections are taken using an optical microscope or an image dimensioning device at a magnification that is easy to measure (for example, 100x magnification, but depending on the size of the hollow fiber membrane, 1000x or 10x magnification may also be used). The captured images are then used with image processing and measurement software to measure the diameter (outer diameter) of the circumscribed circle around the outside of the hollow fiber membrane, and the cross-sectional area is calculated from the radius. The cross-sectional area of ​​the hollow fiber membrane is similarly measured for five images taken of each of the five cut cross sections.

[0017] The above series of measurements is performed on any five hollow fiber membranes, and the average value of the cross-sectional areas obtained at 25 locations is calculated. The total cross-sectional area of ​​the hollow fiber membranes is then calculated from the product of the average cross-sectional area of ​​the hollow fiber membranes obtained and the number of hollow fiber membranes used in the hollow fiber membrane module.

[0018] The cross-sectional areas of the first and second potting parts in the present invention refer to the cross-sectional areas perpendicular to the longitudinal direction of the hollow fiber membranes in the region where the hollow fiber membranes and the module case are fixed by the potting agent, and can be rephrased as the internal area of ​​the module case. The cross-sectional areas of the first and second potting parts can be calculated by measuring the dimensions of appropriate locations depending on the shape of the module case. For example, if the module case is a rectangular prism, the cross-sectional areas can be calculated from the product of the internal dimensions of two perpendicular sides of the module case.

[0019] The packing rate of the hollow fiber membranes in the hollow fiber membrane module can be calculated from the ratio of the total cross-sectional area of ​​the hollow fiber membranes to the cross-sectional areas of the first potting part and the second potting part calculated as above.

[0020] As described above, in the first embodiment, the hollow fiber membranes are arranged spaced apart from one another. Here, "spaced apart" means that the distance between the outer surfaces of a hollow fiber membrane and an adjacent hollow fiber membrane in the cross section of the first potting part and the cross section of the second potting part is greater than the outer diameter of the hollow fiber membrane. Note that it is sufficient that the hollow fiber membranes are spaced apart in the cross section of the first potting part and the cross section of the second potting part, and the hollow fiber membranes in the hollow fiber membrane module other than the potting part may be in partial contact with each other.

[0021] The distance between the hollow fiber membranes in the hollow fiber membrane module is not particularly limited, but is preferably 0.3 mm to 6 mm, and more preferably 1 mm to 6 mm. By setting the distance within this range, it is possible to suppress a decrease in the flow rate of the second fluid passing outside the hollow fiber membranes when passing through the hollow fiber membrane module, and it is possible to suppress an increase in pressure loss and an increase in the size of the hollow fiber membrane module.

[0022] The separation distance of the present invention can be measured by the following method. (1) A cross section of the potting portion of a hollow fiber membrane module is cut out. (2) The obtained cross section is photographed using an optical microscope at a magnification that makes measurement easy. (3) The photographed image is binarized using image processing and measurement software (WinROOF, manufactured by Mitani Shoji Co., Ltd.) while adjusting brightness and contrast as necessary so that the hollow fiber membranes and the potting portion can be distinguished. If the module cross section is too large to observe all at once, the images can be divided and then reassembled to form a single image. (4) The center coordinates of each hollow fiber membrane in the binarized image are measured. (5) Any hollow fiber membrane is selected. (6) The hollow fiber membrane with the closest distance between its outer surface and the outer surface of the hollow fiber membrane selected in (5) is selected. (7) Measure the distance between the center coordinates of the hollow fiber membranes selected in (5) and (6), and use the distance obtained by subtracting the radius of the hollow fiber membrane selected in (5) and the radius of the hollow fiber membrane selected in (6) from that distance as the separation distance between the hollow fiber membranes. (8) Repeat steps (5) to (7) 99 times using hollow fiber membranes other than those selected in (5) and (6). (9) Use the average of the obtained separation distances as the separation distance between the multiple hollow fiber membranes in the hollow fiber membrane module.

[0023] If the number of hollow fiber membranes in the hollow fiber membrane module is less than the number required to achieve the above-mentioned number of measurements, the separation distances for all hollow membranes are measured and the average value obtained is used as the separation distance.

[0024] In the hollow fiber membrane module of the present invention, the larger the exposed area of ​​the hollow fiber membranes, the more efficiently the second fluid contacts the hollow fiber membranes even in a low static pressure environment. Therefore, the area of ​​the openings for exposing the hollow fiber membranes in the longitudinal direction of the hollow fiber membranes in the hollow fiber membrane module of the present invention is preferably 50% or more and 95% or less of the total side surface area of ​​the module case. In the present invention, the side surface of the module case refers to the side surface of the module case when the first potting part and the second potting part are defined as the bottom and top surfaces, respectively. Furthermore, the total side surface area of ​​the module case is defined as the product of the perimeter of the outer dimensions of the side surface of the module case and the effective length of the hollow fiber membranes 1, which is defined by the length from the first potting part 2 to the second potting part 3. The shape of the module case is not particularly limited, and may be, for example, a cylinder, an ellipsoid, a polygonal prism such as a square prism, or an approximately square prism or approximately polygonal prism. However, a square prism is preferred because it can reduce dead space when multiple hollow fiber membrane modules are stacked and used, and it can maintain a uniform length through which the second fluid passes within the module case. Furthermore, the rectangular shape may have rounded or curved corners or sides. The material of the module case is not particularly limited, but preferred materials are described below.

[0025] The material of the potting portion is not particularly limited, but in order to fix the hollow fiber membranes to the module case, it is preferable to use a curable resin because of its ease of handling. More preferred examples include polymer materials such as polyurethane, silicone, and epoxy, or two-component polymer adhesives, and the potting portion that fixes the hollow fiber membranes to the module case is formed by potting using a centrifugal molding method or a static molding method. Therefore, it is preferable that the material of the module case has good adhesion to the curable resin mentioned above. For example, polystyrene, polycarbonate, vinyl chloride, acryl butadiene styrene, polysulfone, etc. are preferably used.

[0026] (Modification of First Embodiment) Figure 2 is a schematic diagram showing an example of the configuration of a hollow fiber membrane module according to a modification of the first embodiment of the present invention. In the first embodiment described above, openings are provided on all four side surfaces of the rectangular module case in the longitudinal direction of the hollow fiber membranes, but this is not limiting and any other configuration may be used as long as openings are provided for the flow of the second fluid. For example, as shown in Figure 2(a), a hollow fiber membrane module 11 according to this modification has a pair of openings 15 at the top and bottom of the four side surfaces of the rectangular module case in the longitudinal direction of the hollow fiber membranes.

[0027] Furthermore, as shown in Fig. 2(b), a hollow fiber membrane module 12 according to another modification has two openings 16 on the side surface of a rectangular prism-shaped module case in the longitudinal direction of the hollow fiber membranes. Fig. 2(b) shows only one side surface of the module case in the longitudinal direction of the hollow fiber membranes, but the remaining three sides also have two openings 16. The partition between the two openings 16 on the side surface of the module case is a partition with the same thickness as the module case, provided between the upper and lower bases of the case, and the inside of the module case is hollow and does not come into contact with the hollow fiber membranes.

[0028] Furthermore, as shown in Fig. 2(c), a hollow fiber membrane module 13 according to yet another modification has 21 substantially circular openings 17 on the side surface of the rectangular module in the longitudinal direction of the hollow fiber membranes. Fig. 2(c) shows only one side surface of the module case in the longitudinal direction of the hollow fiber membranes, but the remaining three sides also have 21 substantially circular openings 17 in the same manner.

[0029] The modifications related to the above-described variations can be similarly made in each of the embodiments described below.

[0030] (Embodiment 2) A hollow fiber membrane module according to Embodiment 2 of the present invention will be described. The hollow fiber membrane module according to Embodiment 2 is a hollow fiber membrane module in which a plurality of hollow fiber membranes are assembled to form a hollow fiber membrane assembly, and the assemblies are spaced apart and connected to the first and second potting parts. As an example of the configuration of a hollow fiber membrane assembly in which a plurality of hollow fiber membranes are assembled, a plurality of hollow fiber membranes can be bundled together. In this case, in the hollow fiber membrane module according to Embodiment 2, a plurality of hollow fiber membrane bundles in which a plurality of hollow fiber membranes are arranged in parallel in a bundle are connected to the first and second potting parts with a space between them. By using a hollow fiber membrane bundle, it is possible to distribute the load on the hollow fiber membranes in response to external loads such as impacts, and by arranging the hollow fiber membrane bundles at a distance from each other, as in embodiment 1, it is possible to reduce the pressure loss of the second fluid flowing outside the hollow fiber membranes through the openings where the hollow fiber membranes are exposed in the longitudinal direction of the hollow fiber membranes, thereby enabling efficient heat or mass transfer with the first fluid flowing inside the hollow fiber membranes.

[0031] FIG. 3 is a schematic diagram showing a configuration example of a hollow fiber membrane module according to a second embodiment of the present invention, including (a) a perspective view, (b) a side view, and (c) a cross-sectional view taken along line II-II' in (b). As shown in FIG. 3, in a hollow fiber membrane module 20 according to the second embodiment, a hollow fiber membrane bundle 28 composed of four hollow fiber membranes 21 is fixed at its first end to a module case 26 via a first potting 22 and its second end via a second potting 23 (not shown). Furthermore, as shown in FIG. 3(c), 12 hollow fiber membrane bundles 28 are fixed at their respective open first and second ends by the first and second pottings 22 and 23, spaced apart from each other. While FIG. 3 illustrates a hollow fiber membrane bundle 28 containing four hollow fiber membranes for ease of explanation, the number of hollow fiber membranes constituting the hollow fiber membrane bundle is not limited to four. On the other hand, when a hollow fiber membrane bundle is constructed using three or more hollow fiber membranes, an area 29 surrounded by the hollow fiber membranes is formed as shown in Figure 3(c). If a hollow fiber membrane bundle is constructed in which the hollow fiber membranes are closely packed, the area of ​​the area 29 becomes too small, preventing penetration of the potting agent and increasing the possibility of poor airtightness of the hollow fiber membrane module. Therefore, it is preferable to form the hollow fiber membrane bundle 28 in a manner that does not result in closely packed hollow fiber membranes.

[0032] In the case of a hollow fiber membrane module according to the second embodiment of the present invention, a plurality of hollow fiber membranes gathered together with the distance between their outer diameters equal to or shorter than the outer diameter of the hollow fiber membranes are considered to be a hollow fiber membrane bundle. In the second embodiment, there is a separation distance between the hollow fiber membrane bundles in the cross sections of the first potting section and the second potting section. It is sufficient that there is a separation distance in the cross sections of the first potting section and the second potting section, and the hollow fiber membranes constituting the hollow fiber membrane bundle in the hollow fiber membrane module other than the potting section may be in partial contact with each other. The separation distance between the hollow fiber membrane bundles is not particularly limited, but is preferably 0.3 mm or more and 6 mm or less, and more preferably 1 mm or more and 6 mm or less. By setting the separation distance within this range, a decrease in the flow rate of the second fluid passing outside the hollow fiber membranes as it passes through the hollow fiber membrane module can be suppressed, thereby suppressing an increase in pressure loss and an increase in the size of the hollow fiber membrane module. The separation distance between the hollow fiber membrane bundles can be measured by the following method. (1) Cut out a cross section 80 of the potting portion of the hollow fiber membrane module. (2) Photograph the obtained cross section using an optical microscope at a magnification that allows easy measurement. (3) Use image processing and measurement software (Mitani Corporation, WinROOF) to binarize the photographed image so that the hollow fiber membrane 82 and the potting portion 81 can be distinguished, adjusting brightness and contrast as necessary. If the module cross section is too large to observe all at once, separate images can be acquired and then reassembled to return to a single image. (4) Measure the central coordinates of each hollow fiber membrane in the binarized image. (5) Calculate the difference between the distance between the central coordinates of adjacent hollow fiber membranes and the radius of each hollow fiber membrane, and identify locations where the distance between the hollow fiber membranes is the same as or shorter than the outer diameter of the hollow fiber membrane, forming a hollow fiber membrane bundle. (6) Any one of the hollow fiber membrane bundles 83 (FIG. 4) is selected, and any one of the hollow fiber membranes constituting the hollow fiber membrane bundle 83 is selected as a hollow fiber membrane 85 from the hollow fiber membranes located at the outermost periphery of the hollow fiber membrane bundle 83. (7) A hollow fiber membrane 86 that is closest to the hollow fiber membrane 85 is selected from among the hollow fiber membrane bundles 83 other than the hollow fiber membrane bundle 83.(8) Calculate the difference between the distance between the center coordinates of hollow fiber membranes 85 and 86 and the sum of the radii of hollow fiber membranes 85 and 86, and use this difference as the separation distance between hollow fiber membrane bundle 83 and hollow fiber membrane bundle 84. (9) Repeat steps (6) to (8) 24 times using hollow fiber membrane bundles not selected in steps (6) to (7). (10) Use the average of the resulting separation distances as the separation distance between hollow fiber membrane bundles in the hollow fiber membrane module.

[0033] If the number of hollow fiber membrane bundles in the hollow fiber membrane module is less than the number required to achieve the above-mentioned number of measurements, the separation distance between all hollow membrane bundles is measured and the average value obtained is used as the separation distance.

[0034] The configuration of the hollow fiber membrane module except for the hollow fiber membrane bundle 28 is the same as that of the first embodiment.

[0035] The hollow fiber membrane bundle of the hollow fiber membrane module according to the second embodiment of the present invention preferably has a covering fiber, which can fix the hollow fiber membrane bundle within the hollow fiber membrane module without the hollow fiber membranes coming apart, thereby improving durability against the load applied when the second fluid comes into contact with the hollow fiber membranes and improving the handleability of the hollow fiber membrane module.

[0036] The term "having a covering yarn" used in the present invention means that two or more hollow fiber membranes are arranged side by side and are wrapped around the entire membrane with a thread-like or strip-like covering yarn to maintain this state. The wrapping method may involve wrapping with multiple threads or strips, or wrapping with a single thread or strip in a spiral shape. The key is to maintain the state in which rod-like or thread-like objects are arranged side by side.

[0037] The covering yarn is preferably one or more of bulky and stretchable crimped yarn, textured yarn, or spun yarn. When these yarns are used as the covering yarn, the hollow fiber membrane unit can be completed online without damaging the hollow fiber membrane when the covering yarn is spirally wound around the hollow fiber membrane. Specifically, fibers with a stretch rate of more than 1% are preferred. Here, "online" refers to completing the membrane unit within a series of processes from the time the hollow fiber membrane is discharged from the spinneret to the time it is wound up.

[0038] The material of the covering yarn is not particularly limited, but examples include polyester, polypropylene, polyphenylene sulfide, and the like.

[0039] (Embodiment 3) A hollow fiber membrane module according to Embodiment 3 of the present invention will be described. The hollow fiber membrane module according to Embodiment 3 is a hollow fiber membrane module in which a plurality of hollow fiber membranes are assembled to form a hollow fiber membrane assembly, and the assemblies are spaced apart and connected to the first and second potting parts. As an example of the configuration of the hollow fiber membrane assembly in which a plurality of hollow fiber membranes are assembled, a hollow fiber membrane sheet layer can be formed in which a plurality of hollow fiber membranes are closely arranged in parallel to form a layer. In this case, the hollow fiber membrane module has a plurality of hollow fiber membrane sheet layers in which a plurality of hollow fiber membranes are closely arranged in parallel to form a layer, and a hollow fiber membrane module is formed in which a plurality of hollow fiber membrane sheet layers are connected to the first and second potting parts with a space between them. By using hollow fiber membranes as hollow fiber membrane sheet layers, it is possible to distribute the load on the hollow fiber membranes in response to external loads such as impacts, and by arranging the hollow fiber membrane sheet layers at a distance from each other, as in embodiment 1, it is possible to reduce the pressure loss of the second fluid flowing outside the hollow fiber membrane through the openings where the hollow fiber membranes are exposed in the longitudinal direction of the hollow fiber membrane, thereby enabling efficient heat or mass transfer with the first fluid flowing inside the hollow fiber membrane.

[0040] FIG. 5 is a schematic diagram showing a configuration example of a hollow fiber membrane module according to a third embodiment of the present invention, including (a) a perspective view, (b) a side view, and (c) a cross-sectional view taken along line III-III' in (b). As shown in FIG. 5 , a hollow fiber membrane module 30 according to the third embodiment has a hollow fiber membrane sheet layer 38 composed of 12 hollow fiber membranes 31, the first end of which is fixed to a module case 36 via a first potting 32 and the second end via a second potting 33 (not shown). Furthermore, as shown in FIG. 5( c), three hollow fiber membrane sheet layers 38 are fixed by the first potting 32 and the second potting 33 at separate locations so that the first and second ends of the three hollow fiber membrane sheet layers 38 are open. While FIG. 5 illustrates a hollow fiber membrane sheet layer 38 for 12 hollow fiber membranes for ease of explanation, the number of hollow fiber membranes constituting the hollow fiber membrane sheet layer is not limited to 12.

[0041] In the hollow fiber membrane module according to embodiment 3, hollow fiber membranes gathered at intervals equal to or shorter than the outer diameter of the hollow fiber membranes are considered to be a hollow fiber membrane sheet layer, and the hollow fiber membrane sheet layers are spaced apart. As long as there is a separation distance between the hollow fiber membrane sheet layers in the cross section of the first potting part and the cross section of the second potting part, it is acceptable for the hollow fiber membranes constituting the hollow fiber membrane sheet layers in the hollow fiber membrane module other than the potting part to be in partial contact with each other.

[0042] The distance between the hollow fiber membrane sheet layers of the hollow fiber membrane module is not particularly limited, but is preferably 0.3 mm to 6 mm, and more preferably 1 mm to 6 mm. By setting the distance within this range, it is possible to suppress a decrease in the flow rate of the second fluid passing outside the hollow fiber membranes when passing through the hollow fiber membrane module, and it is possible to suppress an increase in pressure loss and an increase in the size of the hollow fiber membrane module.

[0043] The separation distance can be measured using the following method. (1) Cut out a cross section 90 of the potting portion of the hollow fiber membrane module (Figure 6). (2) Photograph the obtained cross section using an optical microscope at a magnification suitable for easy measurement. (3) Use image processing and measurement software (WinROOF, manufactured by Mitani Corporation) to binarize the photographed image so that the hollow fiber membrane 92 and the potting portion 91 can be distinguished, adjusting brightness and contrast as necessary. If the module cross section is too large to observe all at once, separate images can be acquired and then reassembled to restore a single image. (4) Measure the central coordinates of each hollow fiber membrane in the binarized image. (5) Calculate the difference between the distance between the central coordinates of adjacent hollow fiber membranes and the sum of the radii of each hollow fiber membrane. Identify the locations where the distance between the hollow fiber membranes is equal to or shorter than the outer diameter of the hollow fiber membrane, forming a hollow fiber membrane sheet layer consisting of multiple hollow fiber membranes. (6) One arbitrary hollow fiber membrane sheet layer 93 is selected, and one arbitrary hollow fiber membrane 95 is further selected from the hollow fiber membranes constituting the hollow fiber membrane sheet layer 93. However, if the hollow fiber membrane sheet layer is composed of multiple rows of hollow fiber membranes, the hollow fiber membrane 95 is selected from the hollow fiber membrane located at the outermost periphery. (7) A hollow fiber membrane 96 having the smallest distance from the hollow fiber membrane 95 is selected from among the hollow fiber membranes other than those constituting the hollow fiber membrane sheet layer 93. (8) Distance 1 is calculated from the difference between the distance between the center coordinates of the hollow fiber membranes 95 and 96 and the sum of the radii of the hollow fiber membranes 95 and 96. (9) From the hollow fiber membranes constituting the hollow fiber membrane sheet layer 93, arbitrary hollow fiber membranes 97 and 99 are selected in addition to the hollow fiber membrane 95. (10) From the hollow fiber membranes constituting hollow fiber membrane sheet layer 94, hollow fiber membranes 98 and 100 that are closest to hollow fiber membranes 97 and 99 are selected, respectively. (11) Distances 2 and 3 are calculated from the difference between the distance between the central coordinates of hollow fiber membranes 97 and 98 and the sum of the radii of the hollow fiber membranes, and from the difference between the distance between the central coordinates of hollow fiber membranes 99 and 100 and the sum of the radii of the hollow fiber membranes. (12) The average of distances 1, 2, and 3 is calculated, and this is used as the separation distance between hollow fiber membrane sheet layer 93 and hollow fiber membrane sheet layer 94.(13) Repeat steps (6) to (12) 19 times using hollow fiber membrane sheet layers other than hollow fiber membrane sheet layer 93 and hollow fiber membrane sheet layer 94. (14) The average value of the obtained separation distances is set as the separation distance of the hollow fiber membrane sheet layers in the hollow fiber membrane module.

[0044] If the number of hollow fiber membrane sheet layers in the hollow fiber membrane module is less than the number required to achieve the above-mentioned number of measurements, the separation distances of all hollow membrane sheet layers are measured and the average value obtained is used as the separation distance.

[0045] The configuration of the hollow fiber membrane module except for the hollow fiber membrane sheet layer 38 is the same as that of the first embodiment.

[0046] The hollow fiber membrane sheet layer of the hollow fiber membrane module according to the third embodiment of the present invention preferably has covering yarns. The effect and material of the covering yarns are the same as those in the second embodiment.

[0047] The configuration of the hollow fiber membrane module of the present invention is not limited to any one of the first to third embodiments, and may be a combination of the first to third embodiments within the same module.

[0048] <Hollow fiber membrane> The hollow fiber membrane is preferably a porous membrane having micropores. Use of a porous membrane enables not only heat exchange but also gas separation via the micropores.

[0049] The material for the hollow fiber membrane is not particularly limited, but it is advisable to select a material that is easy to form a hollow fiber membrane and a gas separation functional layer. For example, in the case of a moisture-permeable hollow fiber membrane module for water vapor, examples include polysulfone-based polymers, polystyrene, polyurethane, polyethylene, polypropylene, polycarbonate, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate, polyvinyl chloride, and polyester. Among these, it is preferable to include a polysulfone-based polymer from the viewpoint of easy formation of a hollow fiber membrane. It is preferable to use a polysulfone-based polymer as the main component and further include a hydrophilic polymer. Examples of hydrophilic polymers include polyalkylene oxides, polyvinyl alcohol, polyethylene glycol, and polyvinylpyrrolidone. Among these, polyvinylpyrrolidone is preferred because it has excellent compatibility with polysulfone-based polymers and is highly hydrophilic.

[0050] The following method is an example of a method for producing hollow fiber membranes. Specifically, a membrane-forming solution prepared by dissolving a polysulfone polymer and polyvinylpyrrolidone in a mixed solution of a good solvent for polysulfone (preferably N,N-dimethylacetamide, dimethyl sulfoxide, dimethylformamide, N-methylpyrrolidone, or dioxane) and a poor solvent is extruded from a double-annular spinneret, with a core liquid flowing inside. After the solution passes through a dry section, it is coagulated in a coagulation solution. Furthermore, from the perspective of process suitability, it is preferable to use a core liquid whose composition is based on the solvent used in the membrane-forming solution. For example, when N,N-dimethylacetamide is used, an aqueous solution with a core liquid concentration of 10 to 60% by mass, or even 20 to 50% by mass, is preferably used.

[0051] The solidified hollow fiber membrane is washed with warm water at 40°C to 90°C and wound up. Next, a heat treatment is performed to fix the pore size to the desired size, resulting in a dry hollow fiber membrane. The size of the pores shrinks when the wet porous membrane is dried after the heat treatment.

[0052] The polysulfone polymer concentration in the membrane-forming solution is preferably 20% by mass or more and 35% by mass or less, more preferably 25% by mass or more and 30% by mass or less, based on the total mass of the membrane-forming solution. If the polysulfone polymer concentration in the membrane-forming solution is less than 20% by mass, the porosity of the hollow fiber membrane increases, and durability tends to decrease.

[0053] The polyvinylpyrrolidone (hereinafter sometimes abbreviated as PVP) added to the membrane-forming solution has a weight-average molecular weight of approximately 10,000 to 1,200,000, with a molecular weight of approximately 40,000 to 1,200,000 being preferred. PVP is preferably used in a ratio of 5 to 50 mass% and more preferably 8 to 30 mass% per 100 mass% of polysulfone-based polymer. If the amount is less than 5 mass% relative to the polysulfone-based polymer, it may be difficult to impart hydrophilicity to the hollow fiber membrane surface, resulting in a concern that the affinity with water vapor may be reduced. If the amount exceeds 50 mass%, the strength of the hollow fiber membrane may be reduced, making membrane formation difficult.

[0054] The hollow fiber membranes produced in this way have controlled phase separation behavior near the outer surface, and are formed as porous membranes. By controlling the pore size of these porous membranes to a size suitable for water vapor permeation, hollow fiber membranes with excellent moisture permeability can be obtained.

[0055] The shape of the hollow fiber membrane is not particularly limited, but a thin membrane is preferable from the viewpoint of moisture or heat exchange, etc. However, if the membrane thickness of the hollow fiber membrane is too thin, problems such as durability may arise, and if it is too thick, moisture or heat exchange efficiency may be reduced. Therefore, the membrane thickness of the hollow fiber membrane is preferably 50 μm or more and 500 μm or less. Furthermore, from the viewpoint of moisture or heat exchange efficiency, the inner diameter of the hollow fiber membrane is preferably 2.0 mm or less, more preferably 1.5 mm or less. Furthermore, if the inner diameter is too small, it becomes difficult to manufacture and the pressure loss when a fluid is passed through it increases, so a diameter of 0.5 mm or more is preferable.

[0056] <Method for manufacturing hollow fiber membrane module> The method for manufacturing a hollow fiber membrane module of the present invention is not particularly limited, but preferably includes the steps of arranging the hollow fiber membranes at a distance from each other, inserting the hollow fiber membranes arranged at a distance into a module case, fixing the hollow fiber membranes to the module case using a potting agent, cutting off the potting agent and hollow fiber membranes that protrude from the module case, and airtightly connecting a first fluid inlet and an outlet to the module case.

[0057] An example of a method for producing the hollow fiber membrane module according to the first embodiment of the present invention shown in FIG. 1 will now be described in detail.

[0058] 7A(a), the hollow fiber membrane 1 is cut to a required length and its ends are temporarily fixed with tape 8 so that they are spaced a predetermined distance apart. As a temporary fixing method, methods using adhesives or jigs other than tape can be used, but there are no particular limitations as long as the hollow fiber membranes can be stably fixed with a certain distance between them.

[0059] 7A(b), the hollow fiber membrane 1 with both ends temporarily fastened is inserted into the module case 6. At this time, the hollow fiber membrane is inserted so that the temporarily fastened areas of the hollow fiber membrane 1 protrude from both ends of the module case 6.

[0060] 7A(c), both ends of the hollow fiber membrane 1 and the module case 6 are fixed together using a potting agent to form the first potting part 2 and the second potting part 3. Methods for forming the first potting part and the second potting part include a method in which the potting agent is poured into the module case while it is being rotated in a centrifuge, and a static method in which the region where the potting part is to be formed is immersed in a container containing the potting agent, but there are no particular limitations as long as the hollow fiber membrane and the module case can be stably fixed together.

[0061] Next, as shown in Fig. 7B(d), the first potting part 2 and the second potting part 3 that protrude from both ends of the module case are cut off to open both ends of the hollow fiber membrane 1. The areas where both ends are temporarily fastened, which were used to space the hollow fiber membrane 1 formed in Fig. 7(a), are cut off at the same time as cutting the first potting part and the second potting part that protrude from the module case.

[0062] 7B(e), a first fluid inlet 4 and a first fluid outlet 5 are connected to both ends of the module case so as to be airtight with the openings at both ends of the hollow fiber membrane, thereby manufacturing the hollow fiber membrane module 10. Alternatively, an O-ring or packing may be used for the connection to ensure an airtight connection.

[0063] Up to this point, an example of a method for manufacturing a hollow fiber membrane module according to the first embodiment of the present invention shown in FIG. 1 has been described. However, by using a hollow fiber membrane bundle or a hollow fiber membrane sheet layer instead of the hollow fiber membrane 1 in the step shown in FIG. 7A(a), it is possible to manufacture a hollow fiber membrane module according to the second embodiment shown in FIG. 3 or a hollow fiber membrane module according to the third embodiment shown in FIG. 5.

[0064] <Possible applications of hollow fiber membrane module> The hollow fiber membrane module of the present invention is applicable to hydrogen production equipment, carbon dioxide separation and recovery equipment, exhaust gas separation and recovery equipment, natural gas separation equipment, deodorization equipment, humidity control equipment, air conditioners such as dehumidifiers, humidifiers, and dehumidifiers and humidifiers, fuel cell systems, desiccant air conditioning systems, and total heat exchangers.

[0065] <Dehumidifier / Humidifier> Next, a dehumidifier / humidifier containing the hollow fiber membrane module of the present invention will be described. This dehumidifier is a device that exchanges water vapor between two fluids via a hollow fiber membrane. For example, this device is a device that supplies air containing water or water vapor to the inside of a hollow fiber membrane and supplies air to the outside of the hollow fiber membrane, causing the water vapor to permeate to the outside of the hollow fiber membrane, thereby humidifying the air supplied to the outside of the hollow fiber membrane. Alternatively, this device is a device that supplies dry air or a hygroscopic liquid such as a lithium chloride aqueous solution to the inside of a hollow fiber membrane and supplies air containing water vapor to the outside of the hollow fiber membrane, causing the water vapor to permeate the hollow fiber membrane, thereby conditioning the humidity of air via the hollow fiber membrane.

[0066] The dehumidifier / humidifier of the present invention can be suitably used in air conditioners, fuel cell systems, and total heat exchangers, but can also be applied to inkjet devices, composting devices, and the like.

[0067] <Air Conditioner> / <Building> Next, we will explain an air conditioner including a dehumidifier / humidifier of the present invention and a building including an air conditioner. This air conditioner is a device such as an air conditioner or air handling unit that controls humidity in ordinary homes, buildings, offices, factories, etc., and a building is an ordinary home, building, office, factory, etc. that is equipped with such an air conditioner.

[0068] The air conditioner of the present invention is a device in which the humidity of the taken-in outside air is adjusted using the above-mentioned dehumidifier / humidifier. An example of a schematic diagram of an air conditioner is shown in Figure 8. When outside air (56) is taken into the air conditioner 50, it passes through an air filter 51, a cooling coil 52, a heating coil 53, a dehumidifier / humidifier 54, and a blower 55 in that order, and is then supplied into the room as air (57). The cooling coil 52 and the heating coil 53 operate depending on whether the room is to be humidified or dehumidified.

[0069] The present invention will be described in more detail below based on examples, but it should be understood that the present invention is not limited to the following examples.

[0070] The preparation of hollow fiber membranes and the evaluation methods used in the examples are explained in the following [1] to [3].

[0071] [1] Measurement of membrane thickness of hollow fiber membrane The hollow fiber membrane was cut in the membrane thickness direction with a single-edged blade and set in a microwatcher (Keyence Corporation, VH-Z100). If the cross section of the hollow fiber membrane was crushed by cutting, the cutting was repeated until it became approximately a perfect circle. An image of the hollow fiber membrane cross section was obtained using a 1000x lens. Next, the number of pixels of the scale bar indicating a known length in the image acquired on the image processing software was counted, the length per pixel (μm) was calculated, and the diameter of the circumscribed circle for the inner and outer surfaces of the hollow fiber membrane in the image was measured. Five cuts were made per hollow fiber membrane, and similar measurements were performed on the five cross sections. A series of measurements was performed on five randomly selected hollow fiber membranes, and the average value was calculated.

[0072] [2] Calculation of packing rate The cross-sectional area A of the inner dimension of a cross section of the rectangular prism module case cut in a direction perpendicular to the longitudinal direction of the hollow fiber membranes was calculated. The total cross-sectional area B of the hollow fiber membranes was calculated from the product of the cross-sectional area of ​​the hollow fiber membranes based on the outer diameter of the hollow fiber membranes and the number of hollow fiber membranes in the module. The packing rate of the hollow fiber membranes in the hollow fiber membrane module was calculated from the ratio of the total cross-sectional area B of the hollow fiber membranes to the cross-sectional area A of the module case.

[0073] [3] Measurement of Moisture Permeability This will be explained with reference to Figure 9. A hollow fiber membrane module 70 and a blower 76 were installed in a temperature-humidity layer 71, and piping through which a first fluid flowed was airtightly connected to a first fluid inlet 74 and a first fluid outlet 75 of the hollow fiber membrane module 70. Dry air, as the first fluid, was flowed inside the hollow fiber membranes via the first fluid inlet 74 and first fluid outlet 75 of the hollow fiber membrane module 70, and moist air, as the second fluid, generated in the temperature-humidity layer 71 by the blower 76 was flowed outside the hollow fiber membranes via an opening in the hollow fiber membrane module 70. Temperature-humidity sensors 72 and 73 were connected before the first fluid inlet 74 and after the first fluid outlet 75, respectively, and the moisture permeability per unit time flowing out of the first fluid outlet 75 was calculated by measuring the relative humidity and temperature.

[0074] Using a 35% by mass lithium chloride aqueous solution at a temperature of 25°C as the first fluid and moist air at a temperature of 25°C and a relative humidity of 80% RH as the second fluid, the moisture permeation rate of the hollow fiber membrane module per unit time was measured, and the water vapor transmission rate per unit area of ​​the hollow fiber membrane was calculated and evaluated according to the following criteria. The membrane area of ​​the hollow fiber membrane module was calculated from the product of the inner diameter of the hollow fiber membrane, the effective length of the hollow fiber membrane, and the number of hollow fibers. A (good): Water vapor transmission rate per unit area of ​​the hollow fiber membrane (g / hr / m ２ ) is 150 or more. B (Acceptable): The water vapor transmission rate (g / hr) per unit area of ​​the hollow fiber membrane is 100 or more and less than 150. C (Not Acceptable): The water vapor transmission rate (g / hr / m) per unit area of ​​the hollow fiber membrane is 100 or more and less than 150. ２ ) is less than 100.

[0075] (Preparation of hollow fiber membrane) 28% by mass of polysulfone ("Udel" P-3500 manufactured by Solvay), 3.0% by mass of polyvinylpyrrolidone (K30 manufactured by BASF), 68% by mass of N,N-dimethylacetamide, and 1% by mass of water (total 100% by mass) were dissolved by heating to prepare a membrane-forming solution. A solution of 30% by mass of N,N-dimethylacetamide and 70% by mass of water (total 100% by mass) was used as a core liquid.

[0076] The membrane-forming solution was sent to the spinneret section and discharged from the outer tube of the orifice-type double-tube spinneret, and the core solution was discharged from the inner tube. The discharged membrane-forming solution passed through a humidity-controlled dry zone atmosphere, then led to a coagulation bath and passed through a water washing process at 40°C, and the resulting wet hollow fiber membrane was wound into a bundle. The wound hollow fiber membrane bundle was dried in a dry heat dryer at 100°C for 24 hours to obtain a dry hollow fiber membrane. When the hollow fiber membrane dimensions were measured, the hollow fiber membrane had an inner diameter of 808 μm and an outer diameter of 1016 μm.

[0077] Example 1 In Example 1, a total of 924 hollow fiber membranes were bundled together and packed into a rectangular prism module case made of polysulfone, with internal dimensions of 65 mm x 35 mm and a length of 270 mm. Both ends of the hollow fiber membranes were potted with a potting agent, and a portion of the end of the potting agent was cut to open both ends of the hollow fiber membrane. A first fluid inlet and a first fluid outlet were attached to form a hollow fiber membrane module A. In hollow fiber membrane module A, the effective length of the hollow fiber membrane not fixed with the potting agent was 250 mm, and the filling rate of the hollow fiber membrane relative to the cross section of the first and second potting sections at both ends of the module case was 32.9%. The moisture permeability of the resulting hollow fiber membrane module A was measured. The results are shown in Table 1.

[0078] Example 2 A hollow fiber membrane module B was produced in the same manner as in Example 1, except that the number of hollow fiber membranes packed was 650, and the packing rate and moisture permeability were measured. The results are shown in Table 1.

[0079] Example 3 In Example 3, a hollow fiber membrane module (see FIG. 1 ) according to the first embodiment of the present invention was fabricated. Specifically, a polysulfone rectangular prism module case with internal dimensions of 65 mm × 35 mm and a length of 270 mm was packed with 200 hollow fiber membranes, arranged in 10 rows with 20 hollow fiber membranes per row, with a 2 mm separation between the hollow fiber membranes. Both ends of the hollow fiber membranes were fixed to the ends of the module case with a potting agent, and portions of the ends of the potting agent were cut to open both ends of the hollow fiber membranes. A first fluid inlet and a first fluid outlet were attached to form a hollow fiber membrane module C. In the hollow fiber membrane module C, the effective length of the hollow fiber membranes not fixed with the potting agent was 250 mm, and the filling rate of the hollow fiber membranes relative to the cross section of the first and second potting sections at both ends of the module case was 7.1%. The moisture permeability of the resulting hollow fiber membrane module C was measured, and the results are shown in Table 1.

[0080] Example 4 In Example 4, a hollow fiber membrane module according to the second embodiment of the present invention (see FIG. 3 ) was fabricated. Specifically, a hollow fiber membrane bundle was formed by spirally wrapping 170 dtex processed polyester yarn around each of four hollow fiber membranes. A total of 50 hollow fiber membrane bundles were then packed into a rectangular polysulfone module case with internal dimensions of 65 mm × 35 mm and a length of 270 mm, with 10 hollow fiber membrane bundles arranged in five rows, with the hollow fiber membrane bundles spaced 2 mm apart. Both ends of the hollow fiber membranes were fixed to the ends of the module case with a potting agent, and portions of the ends of the potting agent were cut to open both ends of the hollow fiber membranes. A first fluid inlet and a first fluid outlet were then attached to form a hollow fiber membrane module D. The effective length of the hollow fiber membranes in hollow fiber membrane module D that was not fixed with the potting agent was 250 mm, and the filling rate of the hollow fiber membranes relative to the cross section of the first potting part and the second potting part at both ends of the module case was 7.1%. The moisture permeability of the obtained hollow fiber membrane module D was measured, and the results are shown in Table 1.

[0081] Example 5 In Example 5, a hollow fiber membrane module E was fabricated in the same manner as in Example 4, except that eight hollow fiber membranes were spirally wrapped with 170 dtex processed polyester yarn to form a hollow fiber membrane bundle, and that a total of 24 hollow fiber membrane bundles were packed in four rows, with six hollow fiber membrane bundles per row, so that the hollow fiber membrane bundles were spaced 7 mm apart. The packing ratio of hollow fiber membranes relative to the cross section of the first and second potting sections at both ends of the module case was 7.0%. The results are shown in Table 1. The large spacing between the hollow fiber membrane bundles increased the amount of second fluid passing through the module interior without coming into contact with the hollow fiber membrane bundles, preventing effective utilization of the moisture permeability of the hollow fiber membranes inside the hollow fiber membrane module, resulting in a moisture permeability rating of B.

[0082] Example 6 In Example 6, a hollow fiber membrane module according to the third embodiment of the present invention (see FIG. 5 ) was fabricated. Specifically, 50 hollow fiber membranes were arranged in parallel, each pair of which was covered by spirally wrapping 170 dtex processed polyester yarn. Eight hollow fiber membrane sheet layers were then stacked and packed into a polysulfone rectangular prism module case with internal dimensions of 65 mm × 35 mm and a length of 270 mm, with the hollow fiber membrane sheet layers spaced 2 mm apart. Both ends of the hollow fiber membranes were fixed to the ends of the module case with a potting agent. The ends of the potting agent were partially cut to open the hollow fiber membranes. A first fluid inlet and a first fluid outlet were then attached to fabricate a hollow fiber membrane module F. The effective length of the hollow fiber membranes in hollow fiber membrane module F that was not fixed with the potting agent was 250 mm, and the filling rate of the hollow fiber membranes relative to the cross section of the first potting part and the second potting part at both ends of the module case was 14.2%. The moisture permeability of the obtained hollow fiber membrane module F was measured, and the results are shown in Table 1.

[0083] Example 7 In Example 7, a hollow fiber membrane module G was produced in the same manner as in Example 6, except that 13 hollow fiber membrane sheet layers were stacked and packed. The packing ratio of the hollow fiber membranes relative to the cross section of the first potting portion and the second potting portion at both ends of the module case was 23.2%. The moisture permeability of the obtained hollow fiber membrane module G was measured, and the results are shown in Table 1.

[0084] Example 8 In Example 8, a hollow fiber membrane module H was produced in the same manner as in Example 6, except that 28 hollow fiber membranes were arranged in parallel to form a hollow fiber membrane sheet layer, and 33 hollow fiber membrane sheet layers were stacked and packed so that the spacing between the hollow fiber membrane sheet layers was 1.5 mm. The filling rate of the hollow fiber membranes relative to the cross section of the first potting portion and the second potting portion at both ends of the module case was 32.9%. The moisture permeability of the obtained hollow fiber membrane module H was measured, and the results are shown in Table 1.

[0085] Comparative Example 1 In Comparative Example 1, a hollow fiber membrane module I was produced in the same manner as in Example 1, except that 1,232 hollow fiber membranes were packed into the module case without considering the spacing between the hollow fiber membranes. The packing rate of the hollow fiber membranes relative to the cross section of the first potting section and the second potting section at both ends of the module case was 43.9%. The moisture permeability of the obtained hollow fiber membrane module I was measured, and the results are shown in Table 1. The packing rate of the hollow fiber membranes was high, so the second fluid could not penetrate into the hollow fiber membrane module, and the moisture permeability of the hollow fiber membranes inside the hollow fiber membrane module could not be effectively utilized, so the moisture permeability was evaluated as C.

[0086]

[0087] REFERENCE SIGNS LIST 1 hollow fiber membrane 2 first potting part 3 second potting part 4 first fluid inlet 5 first fluid outlet 6 module case 7 opening 8 tape 10 hollow fiber membrane module 11 hollow fiber membrane module 12 hollow fiber membrane module 13 hollow fiber membrane module 15 opening 16 opening 17 opening 20 hollow fiber membrane module 21 hollow fiber membrane 22 first potting part 23 second potting part 24 first fluid inlet 25 first fluid outlet 26 module case 27 opening 28 hollow fiber membrane bundle 29 area surrounded by hollow fiber membranes 30 hollow fiber membrane module 31 hollow fiber membrane 32 first potting part 33 second potting part 34 first fluid inlet 35 first fluid outlet 36 module case 37 opening 38 hollow fiber membrane sheet layer 50 Air conditioner 51 Air filter 52 Cooling coil 53 Heating coil 54 Dehumidifier / humidifier 55 Fan 56 Outside air 57 Intake air 70 Hollow fiber membrane module 71 Constant temperature and humidity layer 72 Temperature and humidity sensor 73 Temperature and humidity sensor 74 First fluid inlet 75 First fluid outlet 76 Fan 77 First fluid 78 Second fluid 80 Cross section of potting part of hollow fiber membrane module 81 Potting part 82 Hollow fiber membrane 83 Hollow fiber membrane bundle 84 Hollow fiber membrane bundle 85 Hollow fiber membrane 86 Hollow fiber membrane 87 Separation distance 90 Cross section of potting part of hollow fiber membrane module 91 Potting part 92 Hollow fiber membrane 93 Hollow fiber membrane sheet layer 94 Hollow fiber membrane sheet layer 95 Hollow fiber membrane 96 Hollow fiber membrane 97 Hollow fiber membrane 98 Hollow fiber membrane 99 Hollow fiber membrane 100 Hollow fiber membrane 101 Separation distance 1 102 Separation distance 2 103 Separation distance 3

Claims

1. A hollow fiber membrane module having a plurality of hollow fiber membranes, a first potting section bonding the hollow fiber membranes together so that their first ends are open, a first fluid inlet airtightly connected to the opening of the first ends, a second potting section bonding the hollow fiber membranes together so that their second ends are open, and a first fluid outlet airtightly connected to the opening of the second ends, wherein the filling rate of the plurality of hollow fiber membranes relative to the cross-sectional area of ​​the first potting section and the cross-sectional area of ​​the second potting section in the longitudinal direction of the hollow fiber membranes is between 5% and 40%, and the hollow fiber membrane module has an opening through which the hollow fiber membranes are exposed in the longitudinal direction of the hollow fiber membranes.

2. The hollow fiber membrane module according to claim 1, wherein a hollow fiber membrane assembly is formed by assembling a plurality of the hollow fiber membranes, and the assemblies are spaced apart from each other and connected to the first potting portion and the second potting portion.

3. A hollow fiber membrane module according to claim 2, wherein the hollow fiber membrane assembly is a bundle of hollow fiber membranes, and the hollow fiber membrane bundles are spaced apart from each other and connected to the first potting portion and the second potting portion.

4. The hollow fiber membrane module according to claim 3, wherein the hollow fiber membrane bundle has covering fibers.

5. The hollow fiber membrane module according to claim 4, wherein the hollow fiber membrane assembly is a hollow fiber membrane sheet layer consisting of parallel hollow fiber membranes, and the hollow fiber membrane sheet layers are spaced apart and connected to the first potting portion and the second potting portion.

6. The hollow fiber membrane module according to claim 5, wherein said hollow fiber membrane sheet layer has covering fibers.

7. The hollow fiber membrane module according to claim 2, wherein the distance between the hollow fiber membrane assemblies is 1 mm or more and 6 mm or less.

8. A hollow fiber membrane module according to claim 1, wherein the openings through which the hollow fiber membranes are exposed occupy a range of 50% to 95% of the area of ​​the side surface perpendicular to the longitudinal direction of the hollow fiber membranes.

9. The hollow fiber membrane module according to claim 1, wherein the plurality of hollow fiber membranes are connected to the first potting portion and the second potting portion one by one at a distance.

10. The hollow fiber membrane module according to claim 9, wherein the distance between the plurality of hollow fiber membranes is 1 mm or more and 6 mm or less.

11. The hollow fiber membrane module according to claim 1, wherein the filling rate of the hollow fiber membranes is 5% or more and 30% or less.

12. The hollow fiber membrane module according to claim 1, wherein the hollow fiber membrane is a porous membrane.

13. The hollow fiber membrane module according to claim 12, wherein the hollow fiber membranes comprise a polysulfone-based polymer and polyvinylpyrrolidone.

14. The hollow fiber membrane module according to claim 1, wherein the membrane thickness of the hollow fiber membrane is 50 μm or more and 500 μm or less.

15. The hollow fiber membrane module according to claim 14, wherein the inner diameter of the hollow fiber membrane is 0.5 mm or more and 2.0 mm or less.

16. A dehumidifier / humidifier comprising the hollow fiber membrane module according to claim 13.

17. An air conditioner comprising the dehumidifier / humidifier according to claim 16.

18. A building comprising the air conditioner of claim 17.

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