Degassing module and method for degassing liquids

Abstract

This degassing module comprises: a liquid circulation pipe; a hollow fiber membrane bundle in which a plurality of hollow fiber membranes are bundled; a cylindrical part; a first sealing part that seals among an end part on a first extension direction side of the liquid circulation pipe, an end part on the first extension direction side of the plurality of hollow fiber membranes, and the cylindrical part; a second sealing part that seals among an end part on a second extension direction side of the liquid circulation pipe, an end part on the second extension direction side of the plurality of hollow fiber membranes, and the cylindrical part; a liquid supply port; a liquid discharge port; and a gas port. The ratio of the thickness of the hollow fiber membrane bundle between the first sealing part and the second sealing part to the length in the extending direction of the hollow fiber membrane bundle between the first sealing part and the second sealing part is 0.3 or more.

Description

Technical Field

[0001] The present disclosure relates to a degassing module and a method for degassing a liquid.

Background Art

[0002] Conventionally, a degassing module that degasses a liquid using a degassing module in which a plurality of hollow fiber membranes are arranged around a liquid flow pipe is known (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Degassing of a liquid is often performed in a sweep mode. The sweep mode is a method of degassing a liquid by supplying the liquid to the outside of the hollow fiber membrane and supplying a sweep gas into the hollow fiber membrane. However, in the sweep mode, the gas concentration in the gas phase decreases. In order to degas the gas from the liquid at a high concentration, it is effective to perform the degassing in a vacuum mode. The vacuum mode is a method of degassing a liquid by supplying the liquid to the outside of the hollow fiber membrane and sucking (evacuating) the inside of the hollow fiber membrane. In the vacuum mode, the gas concentration in the gas phase becomes higher than that in the sweep mode, so that the gas can be degassed from the liquid at a higher concentration than in the sweep mode.

[0005] Also, in order to degas the gas from the liquid at a high concentration, it is effective to increase the size of the degassing module and supply a large flow rate of water to the degassing module. When a large flow rate of water is supplied to the degassing module, the degree of vacuum on the gas phase side does not change significantly, whereas the partial pressure of the gas to be degassed on the liquid phase side increases, so that the partial pressure difference of the gas to be degassed between the gas phase side and the liquid phase side increases. As a result, the gas to be degassed is degassed at a high concentration.

[0006] For this reason, the inventors have created multiple degassing modules with different dimensions for each part in order to degas carbon dioxide at a high concentration, and have supplied 50 m to each degassing module. 3 We conducted tests to degas carbon dioxide from water in vacuum mode by supplying a large flow rate of water (over 1 / h). As a result, we found that the degassing performance (separation performance) of some degassing modules deteriorated.

[0007] Therefore, the object of this disclosure is to provide a degassing module and a degassing method for liquids that can suppress a decrease in degassing performance. [Means for solving the problem]

[0008] In order to solve the above problems, the present inventors conducted further research and found that the relationship between the outer diameter of a hollow fiber membrane bundle composed of multiple hollow fiber membranes and the length of the hollow fiber membrane bundle affects the degassing performance. This disclosure is based on the above findings.

[0009] [1] The degassing module according to the present disclosure comprises a liquid flow pipe having a plurality of openings formed therein and a liquid flow passage formed therein; a bundle of hollow fiber membranes arranged around the liquid flow pipe such that the plurality of hollow fiber membranes cover the plurality of openings; a cylindrical portion housing the liquid flow pipe and the bundle of hollow fiber membranes; a first sealing portion sealing the space between the end of the liquid flow pipe on the first extending direction side, the end of the plurality of hollow fiber membranes on the first extending direction side and the cylindrical portion, such that the hollow portions of the plurality of hollow fiber membranes open in the direction opposite to the first extending direction in the extending direction of the liquid flow pipe; and The device includes a second sealing portion that seals the space between the end of the liquid flow pipe on the second extending direction side, the ends of the plurality of hollow fiber membranes on the second extending direction side, and a cylindrical portion, opening in the second extending direction side, a liquid supply port for supplying liquid to the liquid flow pipe, a liquid discharge port provided in the cylindrical portion for discharging liquid that has come out of the liquid flow pipe, and a gas port for discharging gas that has permeated through the plurality of hollow fiber membranes, wherein the ratio of the thickness of the hollow fiber membrane bundle between the first sealing portion and the second sealing portion to the length of the hollow fiber membrane bundle in the extending direction between the first sealing portion and the second sealing portion is 0.3 or more.

[0010] In this degassing module, the ratio of the thickness of the hollow fiber membrane bundle in the extending direction between the first and second sealing parts to the length of the hollow fiber membrane bundle in the extending direction between the first and second sealing parts is 0.3 or more. Therefore, the number of hollow fiber membranes or the membrane area of ​​multiple hollow fiber membranes per unit length in the extending direction of the hollow fiber membrane bundle can be increased. This suppresses a decrease in degassing performance.

[0011] [2] In the degassing module described in [1], the first sealing section and the second sealing section may divide the area inside the cylindrical section into an internal area including the hollow portions of the multiple hollow fiber membranes and an external area including the hollow portions of the liquid flow pipe, with the multiple hollow fiber membranes serving as the boundary. In this degassing module, the first sealing section and the second sealing section divide the area inside the cylindrical section into an internal area including the hollow portions of the multiple hollow fiber membranes and an external area including the liquid flow passage of the liquid flow pipe, with the multiple hollow fiber membranes serving as the boundary. Therefore, the internal area and the external area can be easily separated. The external area is a liquid phase area through which liquid flows, and the internal area is a gas phase area through which gas that has permeated the multiple hollow fiber membranes flows.

[0012] [3] The degassing module described in [1] or [2] further comprises a first lid connected to the end of the cylindrical portion on the first extending direction side and a second lid connected to the end of the cylindrical portion on the second extending direction side, wherein a liquid supply port is provided on the second lid, a liquid discharge port is provided on the cylindrical portion, and a gas port may be provided on at least one of the first lid and the second lid. In this degassing module, the first lid and the second lid are connected to both ends of the cylindrical portion, a liquid supply port is provided on the second lid, a liquid discharge port is provided on the cylindrical portion, and a gas port is provided on at least one of the first lid and the second lid, so the degassing module can be easily manufactured.

[0013] In the degassing module described in [4] [3], the first lid forms a first end communication space that communicates with the hollow portions of a plurality of hollow fiber membranes, and the gas port may have a first end gas port adjacent to the first end communication space and communicating with the first end communication space. In this degassing module, the first lid forms a first end communication space that communicates with the hollow portions of a plurality of hollow fiber membranes, and the first end gas port is adjacent to the first end communication space and communicates with the first end communication space. Therefore, a degassing module that can suck the hollow portions of a plurality of hollow fiber membranes from the end on the first extending direction side can be easily manufactured.

[0014] In the degassing module described in [5] [3] or [4], the second lid forms a second end communication space that communicates with the hollow portions of a plurality of hollow fiber membranes, and the gas port may have a second end gas port adjacent to the second end communication space and communicating with the second end communication space. In this degassing module, the second lid forms a second end communication space that communicates with the hollow portions of a plurality of hollow fiber membranes, and the second end gas port is adjacent to the second end communication space and communicates with the second end communication space. Therefore, a degassing module that can suck the hollow portions of a plurality of hollow fiber membranes from the end on the second extending direction side can be easily manufactured.

[0015] In the degassing module described in any of [6] [3] to [5], the cylindrical portion houses a degassing element in which both ends of a plurality of hollow fiber membranes in the direction of extension are fixed to both ends of a liquid flow pipe in the direction of extension, and at least one of the first lid and the second lid may be detachably connected to the cylindrical portion. In this degassing module, since at least one of the first lid and the second lid is detachably connected to the cylindrical portion, the degassing element can be removed from the cylindrical portion and replaced by removing at least one of the first lid and the second lid from the cylindrical portion. This significantly extends the lifespan of the degassing module.

[0016] In the degassing module described in any of [7] [3] to [6], the volume of the housing having the cylindrical part, the first lid part, and the second lid part may be 10 L or more. In this degassing module, since the volume of the housing is 10 L or more, style A volume of liquid can be supplied to degas the system.

[0017] In the degassing module described in any of [8] [1] to [7], the thickness of each of the multiple hollow fiber membranes may be between 10 μm and 1000 μm. In this degassing module, since the thickness of each of the multiple hollow fiber membranes is between 10 μm and 1000 μm, it is possible to suppress the rupture of the hollow fiber membranes and to obtain a large membrane area by increasing the number of hollow fiber membranes.

[0018] [9] The method for degassing a liquid according to the present disclosure is a method for degassing a liquid using the degassing module described in any one of [1] to [8]. In this method, while sucking air from the gas port into the hollow portions of a plurality of hollow fiber membranes, liquid is supplied from the liquid supply port to the liquid flow pipe. In this liquid degassing method, in any of the above degassing modules, by sucking air from the gas port into the hollow portions of a plurality of hollow fiber membranes and supplying liquid from the liquid supply port to the liquid flow pipe, the liquid is degassed. Therefore, a decrease in degassing performance can be suppressed.

Effects of the Invention

[0019] According to the present disclosure, a decrease in degassing performance can be suppressed.

Brief Description of the Drawings

[0020] [Figure 1] It is a schematic cross-sectional view of a degassing module according to an embodiment. [Figure 2] It is a schematic front view of a degassing element. [Figure 3] It is a schematic cross-sectional view taken along line III-III shown in FIG. 2. [Figure 4] It is a schematic cross-sectional view showing a part of the degassing element shown in FIG. 2. [Figure 5] It is a schematic cross-sectional view showing a part of the degassing element shown in FIG. 2. [Figure 6] It is a schematic cross-sectional view showing a part of an example of a hollow fiber membrane composed of an asymmetric membrane. [Figure 7] It is a schematic cross-sectional view showing a part of the degassing module shown in FIG. 1. [Figure 8] It is a schematic cross-sectional view showing a part of the degassing module shown in FIG. 1. [Figure 9] It is a schematic cross-sectional view showing a part of the degassing module shown in FIG. 1. [Figure 10] It is a graph showing the relationship between the degree of vacuum in the gas phase region and the water vapor transmission rate of the hollow fiber membrane. [Figure 11] It is a schematic cross-sectional view of a degassing module of another example. [Figure 12] This is a schematic cross-sectional view of another example of a degassing module. [Figure 13] This is a schematic cross-sectional view of another example of a degassing module. [Modes for carrying out the invention]

[0021] The degassing module and liquid degassing method of the embodiment will be described below with reference to the drawings. In all the drawings, the same or corresponding parts are denoted by the same reference numerals, and redundant explanations are omitted.

[0022] [Degassing module] Figure 1 is a schematic cross-sectional view of a degassing module according to an embodiment. As shown in Figure 1, the degassing module 1 according to this embodiment is a module for degassing a liquid L. The liquid L is not particularly limited, but examples include water such as tap water, drinking water, pure water, ultrapure water, seawater, and industrial water; aqueous solutions containing ammonium sulfate, surfactants, etc.; organic solvents such as alcohol and hydrocarbons; and ionic liquids. The degassing module 1 comprises a degassing element 2, a housing 3, a closure section 5, and a partition section 7. Note that only the housing 3 is shown in cross-section in Figure 1.

[0023] Figure 2 is a schematic front view of the degassing element. Figure 3 is a schematic cross-sectional view taken along line III-III shown in Figure 2. Figure 4 is a schematic cross-sectional view showing a part of the degassing element shown in Figure 2. Figure 5 is a schematic cross-sectional view showing a part of the degassing element shown in Figure 2. As shown in Figures 1 to 5, the degassing element 2 is for degassing liquid L. The degassing element 2 comprises a liquid flow pipe 21, a hollow fiber membrane bundle 23, a first fixed part 24, and a second fixed part 25.

[0024] The liquid flow pipe 21 is a cylindrical member that extends in the extending direction D2. Of the two directions of the extending direction D2, one direction is called the first extending direction D21, and the other direction is called the second extending direction D22. In Figure 2, the upper part is the first extending direction D21, and the lower part is the second extending direction D22. The end of the degassing element 2 on the first extending direction D21 side is called the first element end 2a, and the end of the degassing element 2 on the second extending direction D22 side is called the second element end 2b.

[0025] The liquid flow pipe 21 forms a liquid flow passage 21a. The liquid flow passage 21a is a flow path (pipe internal flow path) through which liquid L can flow, and is formed by the inner circumferential surface of the liquid flow pipe 21. The liquid flow pipe 21 extends over the entire area in the extending direction D2 of the degassing element 2. That is, the liquid flow pipe 21 extends from the end of the degassing element 2 in the first extending direction D21 to the end of the degassing element 2 in the second extending direction D22. The liquid flow passage 21a of the liquid flow pipe 21 is open in the first extending direction D21 and the second extending direction D22. The opening of the liquid flow passage 21a of the liquid flow pipe 21 on the first extending direction D21 side is called the first end liquid flow pipe opening 21b, and the opening of the liquid flow passage 21a of the liquid flow pipe 21 on the second extending direction D22 side is called the second end liquid flow pipe opening 21c. Furthermore, in the degassing element 2, no baffles or other members are provided in the liquid flow passage 21a of the liquid flow pipe 21 to prevent the liquid L from moving in the direction of extension D2.

[0026] Multiple openings 21d are formed in the liquid flow pipe 21. These multiple openings 21d are holes for allowing liquid L to exit the liquid flow passage 21a to the outside of the liquid flow pipe 21, separate from the first end liquid flow pipe opening 21b and the second end liquid flow pipe opening 21c. In other words, the multiple openings 21d are holes in the radial direction of the liquid flow pipe 21 for allowing liquid L to exit the liquid flow passage 21a to the outside of the liquid flow pipe 21. The multiple openings 21d are formed in the peripheral wall of the liquid flow pipe 21, opening the liquid flow passage 21a to the outside of the liquid flow pipe 21.

[0027] The hollow fiber membrane bundle 23 is constructed by arranging multiple hollow fiber membranes 22 around the liquid flow pipe 21 so as to cover multiple openings 21d. The multiple hollow fiber membranes 22 extend along the liquid flow pipe 21. The statement that the multiple hollow fiber membranes 22 extend along the liquid flow pipe 21 means that in the initial state (unused state) of the degassing element 2, the multiple hollow fiber membranes 22 extend along the extension direction D2. The multiple hollow fiber membranes 22 are bundled together in a cylindrical shape by being arranged around the liquid flow pipe 21. Therefore, the hollow fiber membrane bundle 23 is formed by the multiple hollow fiber membranes 22 into a cylindrical shape extending along the extension direction D2.

[0028] The hollow fiber membrane bundle 23 is formed, for example, by a hollow fiber membrane fabric (not shown) woven in a curtain-like manner. The hollow fiber membrane fabric is a fabric woven with multiple hollow fiber membranes 22 which serve as weft threads and warp threads (not shown). In the hollow fiber membrane fabric, multiple hollow fiber membranes 22 are arranged in a curtain-like manner. The hollow fiber membrane fabric is then wrapped around the liquid flow pipe 21 such that the multiple hollow fiber membranes 22 extend in the extending direction D2 and cover multiple openings 21d.

[0029] The hollow portion 22a of the hollow fiber membrane 22 is a flow path (internal membrane flow path) through which gas G can flow, and is formed by the inner circumferential surface of the hollow fiber membrane 22. The multiple hollow fiber membranes 22 extend over the entire area in the extending direction D2 of the degassing element 2. That is, the multiple hollow fiber membranes 22 extend from the end of the degassing element 2 in the first extending direction D21 to the end of the degassing element 2 in the second extending direction D22. The hollow portions 22a of the multiple hollow fiber membranes 22 are open in the first extending direction D21 and the second extending direction D22. Note that the hollow portion 22a of the multiple hollow fiber membranes 22 refers to the hollow portion 22a of each of the multiple hollow fiber membranes 22. The opening on the first extension direction D21 side of the hollow portion 22a of the multiple hollow fiber membranes 22 is called the first end hollow fiber membrane opening 22b, and the opening on the second extension direction D22 side of the hollow portion 22a of the multiple hollow fiber membranes 22 is called the second end hollow fiber membrane opening 22c.

[0030] The hollow fiber membrane 22 is a hollow fiber membrane that allows gas G to permeate but not liquid L. The material, membrane shape, and membrane form of the hollow fiber membrane 22 are not particularly limited. Examples of materials for the hollow fiber membrane 22 include polyolefin resins such as polypropylene, polyethylene, and polymethylpentene; silicon resins such as polydimethylsiloxane and its copolymers; and fluorine resins such as PTFE and vinylidene fluoride. Examples of membrane shapes (sidewall shapes) of the hollow fiber membrane 22 include porous membranes, microporous membranes, and homogeneous membranes (non-porous membranes) that do not have porosity. Examples of membrane forms of the hollow fiber membrane 22 include symmetrical membranes (homogeneous membranes) in which the chemical or physical structure of the entire membrane is homogeneous, and asymmetrical membranes (heterogeneous membranes) in which the chemical or physical structure of the membrane differs depending on the part of the membrane. An asymmetrical membrane (heterogeneous membrane) is a membrane having a non-porous dense layer and a porous layer. Non-porous means that it does not have pores through which liquid can pass. Porous means having pores through which liquid can pass. In this case, the dense layer may be formed anywhere in the membrane, such as on the surface or inside the porous membrane. Heterogeneous membranes also include composite membranes with different chemical structures and multilayer membranes such as three-layer structures. Heterogeneous membranes using poly-4-methylpentene-1 resin are particularly preferred because they have a dense layer that blocks liquid L.

[0031] Figure 6 is a schematic cross-sectional view showing a part of an example of a hollow fiber membrane composed of an asymmetric membrane. The hollow fiber membrane 22 shown in Figure 6 is composed of an asymmetric membrane having a non-porous dense layer 22d and a porous layer 22e. The dense layer 22d is a layer that does not have pores, i.e., a non-porous layer. A layer that does not have pores means, for example, a layer that does not have pores through which liquid L can pass. Pores through which liquid L can pass mean, for example, pores whose minimum pore diameter is larger than the molecules that make up liquid L. In this case, the dense layer 22d may have pores through which liquid L cannot pass. The porous layer 22e is a porous layer. The porous layer 22e also functions as a layer that supports the dense layer 22d. A porous layer means, for example, a layer that has pores through which liquid L can pass. The porous layer 22e is formed, for example, in a sponge-like manner. The dense layer 22d is located, for example, on the outside (outer surface side) or inside (inner surface side) of the porous layer 22e. From the viewpoint of easily forming the dense layer 22d and making the hollow fiber membrane 22 less wettable, the dense layer 22d may be formed on the outer surface of the hollow fiber membrane 22.

[0032] From the viewpoint of suppressing rupture of the hollow fiber membrane 22, the thickness (outer diameter) of the hollow fiber membrane 22 is, for example, 10 μm or more, preferably 100 μm or more. On the other hand, from the viewpoint of obtaining a large membrane area by increasing the number of hollow fiber membranes 22, the thickness (outer diameter) of the hollow fiber membrane 22 is, for example, 1000 μm or less, preferably 500 μm or less. From these viewpoints, the thickness (outer diameter) of the hollow fiber membrane 22 is, for example, 10 μm or more and 1000 μm or less, preferably 100 μm or more and 500 μm or less.

[0033] The first fixing part 24 is located at the end 2a of the first element and fixes the multiple hollow fiber membranes 22 to the liquid flow pipe 21 so as to seal the space between the liquid flow pipe 21 and the multiple hollow fiber membranes 22 and open the hollow portions 22a of the multiple hollow fiber membranes 22. In other words, the first fixing part 24 fixes the ends of the multiple hollow fiber membranes 22 on the first extending direction D21 side to the liquid flow pipe 21. The first fixing part 24 seals the space between the liquid flow pipe 21 and the multiple hollow fiber membranes 22. Furthermore, the first fixing part 24 is not provided in the liquid flow passage 21a of the liquid flow pipe 21 or the hollow portions 22a of the multiple hollow fiber membranes 22, thus opening the liquid flow passage 21a of the liquid flow pipe 21 and the hollow portions 22a of the multiple hollow fiber membranes 22. The first fixing part 24 is formed of, for example, resin.

[0034] The second fixing part 25 is located at the end 2b of the second element and fixes the multiple hollow fiber membranes 22 to the liquid flow pipe 21 so as to seal the space between the liquid flow pipe 21 and the multiple hollow fiber membranes 22 and open the hollow portions 22a of the multiple hollow fiber membranes 22. In other words, the second fixing part 25 fixes the ends of the multiple hollow fiber membranes 22 on the second extending direction D22 side to the liquid flow pipe 21. The second fixing part 25 seals the space between the liquid flow pipe 21 and the multiple hollow fiber membranes 22. Furthermore, the second fixing part 25 is not provided in the liquid flow passage 21a of the liquid flow pipe 21 or the hollow portions 22a of the multiple hollow fiber membranes 22, thus leaving the liquid flow passage 21a of the liquid flow pipe 21 and the hollow portions 22a of the multiple hollow fiber membranes 22 open. The second fixing part 25 is formed of, for example, resin.

[0035] The first fixing part 24 and the second fixing part 25 fix the multiple hollow fiber membranes 22 to the liquid flow pipe 21, so that the multiple hollow fiber membranes 22 extend along the extension direction D2 and are bundled together in a cylindrical shape, thereby forming the hollow fiber membrane bundle 23 in a cylindrical shape that extends along the extension direction D2.

[0036] Furthermore, the multiple hollow fiber membranes 22 are not covered by any components such as a housing, and are exposed to the outside of the degassing element 2 between the first fixing part 24 and the second fixing part 25.

[0037] Figure 7 is a schematic cross-sectional view showing a portion of the degassing module shown in Figure 1. Figure 8 is a schematic cross-sectional view showing a portion of the degassing module shown in Figure 1. Figure 9 is a schematic cross-sectional view showing a portion of the degassing module shown in Figure 1. As shown in Figures 1, 2, and 7 to 9, the housing 3 accommodates the degassing element 2 such that a gap S1 is formed between it and the degassing element 2. This gap S1 is a space between the degassing element 2 and the housing 3 through which the liquid L can flow.

[0038] The housing 3 comprises a cylindrical portion 31 surrounding the degassing element 2, a first lid portion 32 connected to one end of the cylindrical portion 31, and a second lid portion 33 connected to the end of the cylindrical portion 31 opposite to the first lid portion 32.

[0039] The cylindrical portion 31 is formed in a cylindrical shape extending in the extending direction D1. The extending direction D1 is also the direction opposite to the first lid portion 32 and the second lid portion 33. Of the two directions of the extending direction D1, one direction is called the first extending direction D11, and the other direction is called the second extending direction D12. In Figure 1, the upper part is the first extending direction D11, and the lower part is the second extending direction D12. The cylindrical portion 31 houses the degassing element 2 so as to surround the degassing element 2. In this embodiment, the cylindrical portion 31 houses the degassing element 2 such that the extending direction D2 of the degassing element 2 coincides with the extending direction D1 of the cylindrical portion 31. Therefore, the extending direction D1 of the cylindrical portion 31 and the extending direction D2 of the degassing element 2 are in the same direction.

[0040] The first cover portion 32 is connected to the end of the cylindrical portion 31 on the first extending direction D11 side so as to cover the opening on the first extending direction D11 side of the cylindrical portion 31. The second cover portion 33 is connected to the end of the cylindrical portion 31 on the second extending direction D12 side so as to cover the opening on the second extending direction D12 side of the cylindrical portion 31. The first cover portion 32 and the second cover portion 33 are detachably connected to the cylindrical portion 31. In the housing 3, the degassing element 2 can be removed from the cylindrical portion 31 and replaced by removing at least one of the first cover portion 32 and the second cover portion 33 from the cylindrical portion 31. The detachable connection of the first cover portion 32 and the second cover portion 33 to the cylindrical portion 31 can be made, for example, by screwing or fitting.

[0041] large style From the viewpoint of enabling the degassing of a certain amount of liquid L, the volume inside the housing 3 is, for example, 10 L or more, preferably 20 L or more, and more preferably 40 L or more. Also, the inner diameter of the cylindrical portion 31 is, for example, 10 cm or more, preferably 15 cm or more, and more preferably 20 cm or more. Also, the length of the cylindrical portion 31 in the extending direction D2 is, for example, 20 cm or more, preferably 30 cm or more, and more preferably 40 cm or more.

[0042] The upper limit of the volume inside the housing 3, the upper limit of the length of the cylindrical portion 31 in the extending direction D2, and the upper limit of the inner diameter of the cylindrical portion 31 are not particularly limited. From the viewpoint of ease of manufacture and ease of installation, the volume inside the housing 3 may be, for example, 80 L or less, preferably 70 L or less, and more preferably 60 L or less. The inner diameter of the cylindrical portion 31 may be, for example, 50 cm or less, preferably 40 cm or less, and more preferably 30 cm or less. The length of the cylindrical portion 31 in the extending direction D2 may be, for example, 70 cm or less, preferably 60 cm or less, and more preferably 50 cm or less.

[0043] From these viewpoints, the volume inside the housing 3 may be, for example, 10 L or more and 80 L or less, preferably 20 L or more and 70 L or less, and more preferably 30 L or more and 60 L or less. Also, the inner diameter of the cylindrical portion 31 may be, for example, 10 cm or more and 50 cm or less, preferably 15 cm or more and 40 cm or less, and more preferably 20 cm or more and 30 cm or less. Also, the length of the cylindrical portion 31 in the extending direction D2 may be, for example, 20 cm or more and 70 cm or less, preferably 30 cm or more and 60 cm or less, and more preferably 40 cm or more and 50 cm or less.

[0044] The blocking portion 5 blocks the end 21f of the liquid flow passage 21a of the liquid flow pipe 21 on the first extending direction D21 side. In other words, the blocking portion 5 blocks the liquid flow passage 21a at the end 21f of the liquid flow pipe 21 on the first extending direction D21 side. The blocking portion 5 is fitted into the end of the liquid flow passage 21a of the liquid flow pipe 21 on the first extending direction D21 side. The blocking portion 5 is also called a plug or the like. The blocking portion 5 may be formed integrally with the first lid portion 32. The blocking portion 5 prevents the liquid L supplied to the liquid flow passage 21a of the liquid flow pipe 21 from being discharged from the liquid flow pipe 21 in the first extending direction D21. Therefore, the liquid L is not discharged from the liquid flow pipe 21 in the first extending direction D21, but is discharged radially outward from the liquid flow pipe 21 through a plurality of openings 21d formed in the liquid flow pipe 21.

[0045] Furthermore, the liquid flow passage 21a of the liquid flow pipe 21 is not provided with any member other than the blocking section 5 to prevent the liquid L from moving in the direction of extension D2.

[0046] The partition 7 divides the area within the housing 3 into an internal region R1 and an external region R2, with the multiple hollow fiber membranes 22 serving as the boundary. The external region R2 is the region including the liquid flow passage 21a of the liquid flow pipe 21 and is the liquid phase region to which the liquid L is supplied. The internal region R1 is the region including the hollow portions 22a of the multiple hollow fiber membranes 22 and is the gas phase region through which the gas degassed from the liquid L flows. Therefore, the membranes of the hollow fiber membranes 22 form the boundary between the gas phase region, the internal region R1, and the liquid phase region, the external region R2. In other words, the inside of the hollow fiber membranes 22 (hollow portion 22a) becomes the internal region R1, and the outside of the hollow fiber membranes 22 becomes the external region R2. The multiple hollow fiber membranes 22 prevent the permeation of liquid L from the external region R2 to the internal region R1, while allowing the permeation of gas G (dissolved gas in the liquid L, bubbles contained in the liquid L, etc.) from the external region R2 to the internal region R1. Furthermore, since the liquid flow passage 21a of the liquid flow pipe 21 is in communication with the outside of the liquid flow pipe 21 through a plurality of openings 21d formed in the liquid flow pipe 21, the external region R2 also includes the space S2 outside the liquid flow pipe 21 that is in communication with the liquid flow passage 21a of the liquid flow pipe 21.

[0047] The partition section 7 has a first partition section 71 and a second partition section 72. The first partition section 71 seals the space between the first fixing section 24 and the cylindrical section 31 of the degassing element 2. The second partition section 72 seals the space between the second fixing section 25 and the cylindrical section 31 of the degassing element 2.

[0048] Therefore, the first fixing portion 24 and the first partition portion 71 function as a first sealing portion that seals the space between the end of the liquid flow pipe 21 on the D21 side in the first extending direction, the ends of the multiple hollow fiber membranes 22 on the D21 side in the first extending direction, and the cylindrical portion 31, so that the hollow portions 22a of the multiple hollow fiber membranes 22 open towards the D21 side in the first extending direction. Furthermore, the second fixing portion 25 and the second partition portion 72 function as a second sealing portion that seals the space between the end of the liquid flow pipe 21 on the D22 side in the second extending direction, the ends of the multiple hollow fiber membranes 22 on the D22 side in the second extending direction, and the cylindrical portion 31, so that the hollow portions 22a of the multiple hollow fiber membranes 22 open towards the D22 side in the second extending direction. Furthermore, the first fixing portion 24 and the first partition portion 71, which function as the first sealing portion, and the second fixing portion 25 and the second partition portion 72, which function as the second sealing portion, divide the area within the cylindrical portion 31 into an internal region R1 and an external region R2, with the multiple hollow fiber membranes 22 serving as the boundary.

[0049] Here, the length of the hollow fiber membrane bundle 23 in the extending direction D2 between the first fixed portion 24 and the first partition portion 71, which function as the first sealing portion, and the second fixed portion 25 and the second partition portion 72, which function as the second sealing portion, is referred to as the length L23 of the hollow fiber membrane bundle 23. The length L23 of the hollow fiber membrane bundle 23 is the length in the extending direction D2 of the portion of the hollow fiber membrane bundle 23 that functions as a degassing membrane. For this reason, the portion of the hollow fiber membrane bundle 23 sealed by the first and second sealing portions does not function as a degassing membrane and is therefore excluded from the length L23 of the hollow fiber membrane bundle 23. In this disclosure, since the first partition portion 71 and the second partition portion 72 are located spaced apart from the hollow fiber membrane bundle 23, the length L23 of the hollow fiber membrane bundle 23 is the length of the hollow fiber membrane bundle 23 in the extending direction D1 between the first fixed portion 24 and the second fixed portion 25.

[0050] Furthermore, the thickness of the hollow fiber membrane bundle 23 between the first fixing portion 24 and the first partition portion 71, which function as the first sealing portion, and the second fixing portion 25 and the second partition portion 72, which function as the second sealing portion, is defined as the thickness D23 of the hollow fiber membrane bundle 23. The thickness D23 of the hollow fiber membrane bundle 23 is the thickness of the portion of the hollow fiber membrane bundle 23 that functions as a degassing membrane. For this reason, the portion of the hollow fiber membrane bundle 23 that is sealed by the first sealing portion and the second sealing portion does not function as a degassing membrane and is therefore excluded from the thickness D23 of the hollow fiber membrane bundle 23. In this disclosure, the thickness D23 of the hollow fiber membrane bundle 23 is the thickness of the hollow fiber membrane bundle 23 between the first fixing portion 24 and the second fixing portion 25. If the thickness D23 of the hollow fiber membrane bundle 23 differs in the extending direction D1, the thickness D23 of the hollow fiber membrane bundle 23 is the maximum thickness of the hollow fiber membrane bundle 23 between the second fixing portion 25 and the second partition portion 72. Since the hollow fiber membrane bundle 23 is composed of multiple hollow fiber membranes 22 bundled together in a cylindrical shape, in this disclosure, the thickness D23 of the hollow fiber membrane bundle 23 is defined as the thickness (diameter) of the circumscribed circles of the multiple hollow fiber membranes 22. The thickness D23 of the hollow fiber membrane bundle 23 is also the diameter of the hollow fiber membrane bundle 23.

[0051] Furthermore, the ratio of the thickness D23 of the hollow fiber membrane bundle 23 to the length L23 (D23 / L23) is 0.3 or more, preferably 0.35 or more, and more preferably 0.38 or more. The upper limit of the ratio of the thickness D23 of the hollow fiber membrane bundle 23 to the length L23 (D23 / L23) is not particularly limited. From the viewpoint of suppressing the outer diameter of the degassing module 1 from becoming too large, the ratio of the thickness D23 of the hollow fiber membrane bundle 23 to the length L23 (D23 / L23) may be, for example, 1 or less, preferably 0.8 or less, and more preferably 0.6 or less.

[0052] The length L23 of the hollow fiber membrane bundle 23 is not particularly limited, but may be, for example, 20 cm or more and 70 cm or less, preferably 30 cm or more and 60 cm or less, and more preferably 40 cm or more and 50 cm or less. The thickness D23 of the hollow fiber membrane bundle 23 is not particularly limited, but may be, for example, 10 cm or more and 50 cm or less, preferably 15 cm or more and 40 cm or less, and more preferably 20 cm or more and 30 cm or less.

[0053] A first end communication space S3 is formed on the first extending direction D21 side of the degassing element 2, communicating with the hollow portions 22a of the multiple hollow fiber membranes 22. A second end communication space S4 is also formed on the second extending direction D22 side of the degassing element 2, communicating with the hollow portions 22a of the multiple hollow fiber membranes 22. Since the first end communication space S3 and the second end communication space S4 are communicating with the hollow portions 22a of the multiple hollow fiber membranes 22, they are also part of the internal region R1.

[0054] The first end communication space S3 is the space surrounded by the first fixing portion 24, the first partition portion 71, and the first lid portion 32 of the degassing element 2. The first end communication space S3 is also the space adjacent to the first extending direction D21 side of the first element end portion 2a of the degassing element 2. Furthermore, the first end communication space S3 is the space adjacent to the first end hollow fiber membrane opening 22b of the degassing element 2.

[0055] The second end communication space S4 is the space enclosed by the second fixing portion 25, the second partition portion 72, and the second lid portion 33 of the degassing element 2. The second end communication space S4 is also the space adjacent to the second extending direction D22 side of the second element end portion 2b of the degassing element 2. Furthermore, the second end communication space S4 is the space adjacent to the second end hollow fiber membrane opening 22c of the degassing element 2.

[0056] Space S2 is the space enclosed by the liquid flow pipe 21 of the degassing element 2, the plurality of hollow fiber membranes 22, the first fixed part 24, the second fixed part 25, the cylindrical part 31, the first partition part 71, and the second partition part 72. Furthermore, space S2 is adjacent to the second extending direction D22 side of the first fixed part 24 and the first partition part 71 of the degassing element 2, and also adjacent to the first extending direction D21 side of the second fixed part 25 and the second partition part 72 of the degassing element 2.

[0057] Furthermore, the first partition portion 71 seals the space between the first fixing portion 24 of the degassing element 2 and the cylindrical portion 31, thereby fixing the first fixing portion 24 of the degassing element 2 to the cylindrical portion 31. The second partition portion 72 seals the space between the second fixing portion 25 of the degassing element 2 and the cylindrical portion 31, thereby fixing the second fixing portion 25 of the degassing element 2 to the cylindrical portion 31. The first partition portion 71 and the second partition portion 72 are formed of, for example, resin.

[0058] The housing 3 includes a liquid supply port 35 for supplying liquid L to the liquid flow passage 21a of the liquid flow pipe 21, a liquid discharge port 36 for discharging the liquid L that has come out of the liquid flow pipe 21, and a first end gas port 38 and a second end gas port 39, which are gas ports for discharging gas that has permeated through the plurality of hollow fiber membranes 22. When degassing liquid L in vacuum mode, the first end gas port 38 and the second end gas port 39 are also called vacuum ports, etc. The liquid supply port 35, the liquid discharge port 36, the first end gas port 38, and the second end gas port 39 may be integrally configured with the housing 3, or they may be separate components from the housing 3.

[0059] The liquid supply port 35 is provided in the second lid portion 33 and is a port that connects the inside and outside of the housing 3. The liquid supply port 35 extends in a pipe-like manner from the second lid portion 33 into the inside of the housing 3 and is connected to the end portion 21e of the liquid flow pipe 21 on the second extending direction D22 side. The liquid supply port 35 is then in communication with the liquid flow passage 21a of the liquid flow pipe 21.

[0060] The liquid discharge port 36 is provided in the cylindrical portion 31 and is a port that connects the inside and outside of the housing 3. The liquid discharge port 36 is provided, for example, near the end of the cylindrical portion 31 on the first extending direction D11 side. The liquid discharge port 36 is adjacent to space S2 and communicates with space S2.

[0061] The first end gas port 38 is provided in the first lid portion 32 and is a port that connects the inside and outside of the housing 3. The first end gas port 38 is adjacent to the first end communication space S3 and communicates with the first end communication space S3.

[0062] The second end gas port 39 is provided in the second lid portion 33 and is a port that connects the inside and outside of the housing 3. The second end gas port 39 is adjacent to the second end communication space S4 and communicates with the second end communication space S4.

[0063] [Method for degassing liquids] Next, we will describe a method for degassing liquid L using the degassing module 1. Here, as an example of a method for degassing liquid L, we will describe a method of degassing liquid L using vacuum mode.

[0064] In this degassing method, the first end gas port 38 and the second end gas port 39 of the degassing module 1 are suctioned, and liquid L is supplied to the liquid supply port 35 of the degassing module 1. Suction of the first end gas port 38 and the second end gas port 39 can be performed, for example, by connecting the first end gas port 38 and the second end gas port 39 to a suction device (not shown), such as a vacuum pump, via piping, and operating this suction device. The liquid L can be supplied to the liquid supply port 35, for example, by connecting the liquid supply port 35 to a liquid supply device (not shown), such as a liquid transfer pump that delivers liquid L via piping, and operating this liquid supply device.

[0065] When the first end gas port 38 and the second end gas port 39 are suctioned, the internal region R1 connected to the first end gas port 38 and the second end gas port 39 is suctioned, and the internal region R1 becomes depressurized. Also, when liquid L is supplied to the liquid supply port 35, the liquid L is supplied to the external region R2 connected to the liquid supply port 35. The liquid L supplied to the liquid supply port 35 is supplied to the liquid flow passage 21a of the liquid flow pipe 21. The liquid L is then discharged into space S2 from multiple openings 21d of the liquid flow pipe 21 and comes into contact with multiple hollow fiber membranes 22. At this time, since the hollow portions 22a of the multiple hollow fiber membranes 22 are depressurized, gases G such as dissolved gases in the liquid L and bubbles contained in the liquid L permeate through the multiple hollow fiber membranes 22. As a result, the liquid L is degassed. The degassed liquid L discharged into space S2 is discharged from the liquid discharge port 36. The gas G that has permeated through the multiple hollow fiber membranes 22 is discharged from the first end gas port 38 and the second end gas port 39 after passing through the hollow portions 22a of the multiple hollow fiber membranes 22, the first end communication space S3, and the second end communication space S4.

[0066] As described above, in the degassing module 1 according to this embodiment, the ratio of the thickness D23 of the hollow fiber membrane bundle 23 to the length L23 of the hollow fiber membrane bundle 23 (D23 / L23) is 0.3 or more, preferably 0.35 or more, and more preferably 0.38 or more. Therefore, the number of hollow fiber membranes 22 or the membrane area of ​​multiple hollow fiber membranes 22 per unit length in the extending direction D1 of the hollow fiber membrane bundle 23 can be increased. This makes it possible to suppress a decrease in degassing performance.

[0067] Furthermore, in this degassing module 1, the liquid supply port 35 is connected to the end 21e on the second extending direction D22 side of the liquid flow pipe 21, and the end 21f on the first extending direction D21 side of the liquid flow pipe 21 is blocked. Therefore, when the first end gas port 38 and the second end gas port 39 are sucked and liquid L is supplied to the liquid supply port 35, the liquid L is supplied to the liquid flow pipe 21, exits the liquid flow pipe 21 through the multiple openings 21d, and is degassed upon contact with the multiple hollow fiber membranes 22. After that, the liquid L that has been degassed upon contact with the multiple hollow fiber membranes 22 is discharged from the liquid discharge port 36 without returning to the liquid flow pipe 21. In other words, the liquid L does not flow in a direction that presses the multiple hollow fiber membranes 22 against the liquid flow pipe 21, but flows in a direction that moves the multiple hollow fiber membranes 22 away from the liquid flow pipe 21. This suppresses the increase in pressure loss as the liquid L passes through the multiple hollow fiber membranes 22, thereby suppressing a decrease in the flow rate of the liquid L. As a result, for example, a relatively low-power liquid supply device can be used to supply liquid L to the degassing module 1.

[0068] Furthermore, in this degassing module 1, the first fixed part 24 and first partition part 71, which function as the first sealing part, and the second fixed part 25 and second partition part 72, which function as the second sealing part, divide the area within the cylindrical part 31 into an internal area R1, which is the gas phase area, and an external area R2, which is the liquid phase area. Therefore, the internal area R1 and the external area R2 can be easily separated. The external area R2 is the liquid phase area through which liquid L flows, and the internal area R1 is the gas phase area through which gas G that has permeated through the multiple hollow fiber membranes 22 flows.

[0069] Furthermore, in this degassing module 1, a first lid 32 and a second lid 33 are connected to both ends of the cylindrical portion 31, a liquid supply port 35 is provided in the second lid 33, a liquid discharge port 36 is provided in the cylindrical portion 31, and a first end gas port 38 and a second end gas port 39 are provided in the first lid 32 and the second lid 33, so the degassing module 1 can be easily manufactured.

[0070] Furthermore, in this degassing module 1, the first lid portion 32 forms a first end communication space S3 that communicates with the hollow portions 22a of the multiple hollow fiber membranes 22, and the first end gas port 38 is adjacent to the first end communication space S3 and communicates with the first end communication space S3. Therefore, a degassing module 1 that can suck the hollow portions 22a of the multiple hollow fiber membranes 22 from the end on the first extending direction D21 side can be easily manufactured.

[0071] Furthermore, in this degassing module 1, the second lid portion 33 forms a second end communication space S4 that communicates with the hollow portions 22a of the multiple hollow fiber membranes 22, and the second end gas port 39 is adjacent to the second end communication space S4 and communicates with the second end communication space S4. Therefore, a degassing module 1 that can suck the hollow portions 22a of the multiple hollow fiber membranes 22 from the end on the second extending direction D22 side can be easily manufactured.

[0072] Furthermore, in this degassing module 1, at least one of the first lid 32 and the second lid 33 is detachably connected to the cylindrical portion 31. Therefore, by removing at least one of the first lid 32 and the second lid 33 from the cylindrical portion 31, the degassing element 2 can be removed from the cylindrical portion 31 and replaced. This significantly extends the lifespan of the degassing module 1.

[0073] Furthermore, in this degassing module 1, the volume of the housing 3 is 10 L or more, preferably 20 L or more, more preferably 40 L or more, therefore styleDegassing can be achieved by supplying a large amount of liquid L. When a large flow rate of water is supplied to the degassing module 1, the vacuum level in the internal region R1, which is the gas phase region, does not change significantly, while the partial pressure of the gas to be degassed in the external region R2, which is the liquid phase region, increases. As a result, the partial pressure difference of the gas to be degassed between the gas phase region and the liquid phase region increases. Consequently, the gas to be degassed is degassed at a high concentration. Therefore, by supplying a large flow rate of water to the degassing module 1, the gas to be degassed can be degassed at a high concentration. Moreover, since the ratio of the thickness D23 of the hollow fiber membrane bundle 23 to the length L23 of the hollow fiber membrane bundle 23 (D23 / L23) is 0.3 or more, preferably 0.35 or more, and more preferably 0.38 or more, a decrease in degassing performance can be suppressed even when a large flow rate of water is supplied to the degassing module 1.

[0074] Furthermore, in this degassing module 1, since the thickness of each of the multiple hollow fiber membranes 22 is 10 μm or more and 1000 μm or less, preferably 100 μm or more and 500 μm or less, it is possible to suppress the rupture of the hollow fiber membranes 22 and to obtain a large membrane area by increasing the number of hollow fiber membranes 22.

[0075] Furthermore, in this degassing module 1, since each of the multiple hollow fiber membranes 22 has a dense layer 22d, the amount of water vapor that permeates from the liquid phase region (outer region R2) to the gas phase region (inner region R1) can be reduced. As a result, gas can be degassed from the liquid at a high concentration.

[0076] Here, water was degassed using two degassing modules: one using an asymmetric membrane with a dense layer and a porous layer as the hollow fiber membrane 22, and another using a microporous membrane as the hollow fiber membrane 22. The vacuum level [torr] in the internal region R1, which is the gas phase region, and the water vapor permeation rate [L / min] through the hollow fiber membrane 22 were measured. The vacuum level in the internal region R1, which is the gas phase region, was measured using a vacuum gauge attached to the piping connected to the first end gas port 38 and the second end gas port 39. The water vapor permeation rate through the hollow fiber membrane 22 was measured by the amount of water vapor contained in the gas recovered from the first end gas port 38 and the second end gas port 39. The results are shown in Figure 10.

[0077] Figure 10 is a graph showing the relationship between the vacuum level in the gas phase region and the amount of water vapor permeate through the hollow fiber membrane. In Figure 10, the dashed line A shows the measurement results of the degassing module 1 using an asymmetric membrane having a dense layer and a porous layer as the hollow fiber membrane 22, and the solid line B shows the measurement results of the degassing module 1 using a microporous membrane as the hollow fiber membrane 22. As shown in Figure 10, at the same vacuum level, it can be seen that the amount of water vapor permeate is significantly less when using an asymmetric membrane having a dense layer and a porous layer as the hollow fiber membrane 22 than when using a microporous membrane as the hollow fiber membrane 22. This is presumed to be because the dense layer greatly restricts the permeation of water vapor. From these results, it can be seen that by having a dense layer 22d in each of the multiple hollow fiber membranes 22, the amount of water vapor permeating from the liquid phase region (external region R2) to the gas phase region (internal region R1) can be reduced, thereby enabling high-concentration degassing of gas from the liquid.

[0078] In the liquid degassing method according to this disclosure, the degassing module 1 sucks the hollow portions 22a of the multiple hollow fiber membranes 22 from the first end gas port 38 and the second end gas port 39, and simultaneously supplies liquid L to the liquid flow pipe 21 from the liquid supply port 35, thereby degassing the liquid L. This makes it possible to suppress a decrease in degassing performance.

[0079] Furthermore, in this liquid degassing method, water is supplied as liquid L from the liquid supply port 35 to the liquid flow pipe 21, allowing for high-concentration degassing of gas from the water.

[0080] While preferred embodiments of this disclosure have been described above, this disclosure is not limited to the embodiments described above.

[0081] For example, in the above embodiment, the liquid discharge port was described as being located near the end of the cylindrical portion on the first extending direction side, but it may be located at any position on the cylindrical portion. Figure 11 is a schematic cross-sectional view of another example of a degassing module. In the degassing module 1A shown in Figure 11, the liquid discharge port 36 is located in the central part of the cylindrical portion 31 in the extending direction D1.

[0082] Furthermore, although the above embodiment was described as having gas ports provided on both the first lid and the second lid, they may be provided on only one of the first or second lid.

[0083] Furthermore, although the above embodiment was described as supplying the liquid from the liquid supply port to the liquid flow pipe without any special treatment, the liquid may be heated before being supplied from the liquid supply port to the liquid flow pipe, or an acid may be added to the liquid before it is supplied from the liquid supply port to the liquid flow pipe.

[0084] Figure 12 is a schematic cross-sectional view of another example of a degassing module. The degassing module 1B shown in Figure 12 is basically the same as the degassing module 1 according to the above embodiment, but further includes a heating device 8 for heating the liquid L supplied to the liquid supply port 35. The heating device 8 is, for example, attached to a pipe 10 connected to the liquid supply port 35, and is configured to heat the liquid L flowing through the pipe 10 by heating the pipe 10. For example, a heat exchanger can be used as the heating device 8. In this way, by providing a heating device 8 for heating the liquid L supplied to the liquid supply port 35, heated liquid L is supplied to the liquid supply port 35. The gas G dissolved in the liquid L becomes easier to release when heated. Therefore, gas G can be degassed from the liquid L at a high concentration.

[0085] Figure 13 is a schematic cross-sectional view of another example of a degassing module. The degassing module 1C shown in Figure 13 is basically the same as the degassing module 1 according to the above embodiment, but further includes an acid addition device 9 that adds acid to the liquid L supplied to the liquid supply port 35. The acid addition device 9 is attached, for example, to a pipe 10 connected to the liquid supply port 35, and is configured to add acid to the liquid L by supplying acid to the pipe 10. Examples of acids to be added to the liquid L include hydrochloric acid, hypochlorous acid, sulfuric acid, nitric acid, phosphoric acid, boric acid, acetic acid, citric acid, formic acid, and oxalic acid. In this way, by providing the acid addition device 9 that adds acid to the liquid L supplied to the liquid supply port 35, oxidized liquid L is supplied to the liquid supply port 35. Gases G such as carbon dioxide dissolved in the liquid L become more easily released when oxidized. Therefore, gases G such as carbon dioxide can be degassed from the liquid L at a high concentration. [Explanation of Symbols]

[0086] 1... Degassing module, 1A... Degassing module, 1B... Degassing module, 1C... Degassing module, 2... Degassing element, 2a... First element end, 2b... Second element end, 3... Housing, 5... Closure section, 7... Partition section, 8... Heating device, 9... Acid addition device, 10... Piping, 21... Liquid flow pipe, 21a... Liquid flow passage, 21b... First end liquid flow pipe opening, 21c... Second end liquid flow pipe opening, 21d... Opening, 21e... End, 21f... End, 22... Hollow fiber membrane, 22a... Hollow section, 22b... First end hollow fiber membrane opening, 22c... Second end hollow fiber membrane opening, 22d... Dense layer, 22e... Porous layer, 23... Hollow fiber membrane bundle, 24... First solid fixed part (first sealing part), 25...second fixing part (second sealing part), 31...cylindrical part, 32...first lid part, 33...second lid part, 35...liquid supply port, 36...liquid discharge port, 38...first end gas port, 39...second end gas port, 71...first partition part (first sealing part), 72...second partition part (second sealing part), D1...extending direction, D1 1...first extension direction, D12...second extension direction, D2...extension direction, D21...first extension direction, D22...second extension direction, D23...thickness of hollow fiber membrane bundle, G...gas, L...liquid, L23...length of the hollow fiber membrane bundle, R1...internal region, R2...external region, S1...gap, S2...space, S3...first end communication space, S4...second end communication space.

Claims

1. A liquid flow pipe having multiple openings formed to create liquid flow passages inside, A bundle of hollow fiber membranes arranged around the liquid flow pipe such that multiple hollow fiber membranes cover the multiple openings, A housing comprising: a cylindrical portion for housing the liquid flow pipe and the hollow fiber membrane bundle; a first lid portion connected to the end of the cylindrical portion on the first extending direction side, which is one direction in the extending direction of the liquid flow pipe; and a second lid portion connected to the end of the cylindrical portion on the second extending direction side, which is the direction opposite to the first extending direction in the extending direction; A first sealing portion is provided to seal the space between the end of the liquid flow pipe on the first extending direction side, the end of the multiple hollow fiber membranes on the first extending direction side, and the cylindrical portion, such that the hollow portions of the multiple hollow fiber membranes open toward the first extending direction side. A second sealing portion is provided to seal the space between the end of the liquid flow pipe on the second extending direction, the end of the multiple hollow fiber membranes on the second extending direction, and the cylindrical portion, such that the hollow portions of the multiple hollow fiber membranes open to the second extending direction. A liquid supply port for supplying liquid to the aforementioned liquid flow pipe, A liquid discharge port is provided in the cylindrical portion for discharging the liquid that has come out of the liquid flow pipe, The system includes a gas port for discharging gas that has permeated through the plurality of hollow fiber membranes, The volume of the housing is 10 L or more. The ratio of the thickness of the hollow fiber membrane bundle between the first sealing portion and the second sealing portion to the length of the hollow fiber membrane bundle in the extending direction between the first sealing portion and the second sealing portion is 0.3 or more. Degassing module.

2. The volume of the housing is 80 L or less. The degassing module according to claim 1.

3. The length of the hollow fiber membrane bundle in the extending direction between the first sealing portion and the second sealing portion is 20 cm or more and 70 cm or less. The degassing module according to claim 1.

4. The thickness of the hollow fiber membrane bundle between the first sealing portion and the second sealing portion is 10 cm or more and 50 cm or less. The degassing module according to claim 1.

5. The first sealing portion and the second sealing portion divide the area within the cylindrical portion into an internal region including the hollow portion of the plurality of hollow fiber membranes and an external region including the hollow portion of the liquid flow pipe, with the plurality of hollow fiber membranes serving as the boundary. The degassing module according to claim 1.

6. The liquid supply port is provided in the second lid, The liquid discharge port is provided in the cylindrical portion, The gas port is provided in at least one of the first lid and the second lid. The degassing module according to claim 1.

7. The first lid portion forms a first end communication space that communicates with the hollow portions of the plurality of hollow fiber membranes, The gas port has a first end gas port adjacent to the first end communication space and communicating with the first end communication space. The degassing module according to claim 6.

8. The second lid portion forms a second end communication space that communicates with the hollow portion of the plurality of hollow fiber membranes, The gas port has a second end gas port adjacent to the second end communication space and communicating with the second end communication space. The degassing module according to claim 6.

9. The cylindrical portion houses a degassing element in which both ends of the plurality of hollow fiber membranes in the extending direction are fixed to both ends of the liquid flow pipe in the extending direction. At least one of the first lid and the second lid is detachably connected to the cylindrical portion. The degassing module according to claim 6.

10. The thickness of each of the aforementioned multiple hollow fiber membranes is between 10 μm and 1000 μm. The degassing module according to claim 1.

11. A method for degassing a liquid using a degassing module according to any one of claims 1 to 10, The hollow portions of the plurality of hollow fiber membranes are drawn in from the gas port, and the liquid is supplied to the liquid flow pipe from the liquid supply port. A method for degassing liquids.

Images