JP7790637B2 - Degassing module and liquid degassing method - Google Patents

Description

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

Degassing modules that degas a liquid using multiple hollow fiber membranes have been known for some time. One such degassing module is the contactor shown in Figure 4 of Patent Document 1. This contactor includes a perforated pipe, multiple hollow fiber membranes surrounding the pipe, a pair of tube sheets that secure the ends of the multiple hollow fiber membranes to the pipe, a shell that houses the multiple hollow fiber membranes, an air inlet formed in the shell, and a liquid outlet (housing inlet/outlet) formed between the pair of tube sheets in the shell. When liquid is supplied through the liquid inlet (pipe inlet/outlet) of the pipe, the liquid exits the holes in the pipe, passes through the intermembrane spaces between the multiple hollow fiber membranes, and is discharged through the liquid outlet. At this time, vacuum suction is applied to the lumen of the hollow fiber membranes through the air inlet, moving entrained gas in the liquid toward the lumen of the hollow fiber membranes and degassing the liquid.

Japanese Patent Application Laid-Open No. 2003-038904

However, when the present inventor analyzed a degassing module in which liquid coming out of a pipe hole passes through the intermembrane space between multiple hollow fiber membranes and is discharged from the housing's liquid supply/discharge port, he found that there was variation in the liquid flow rate within the housing. Variations in the liquid flow rate within the housing may result in insufficient degassing performance.

Therefore, the objective of the present disclosure is to provide a degassing module and a method for degassing a liquid that can reduce variation in the flow rate of the liquid within the housing.

The present inventors conducted further intensive research into the above-mentioned issue and found that the liquid flow rate was low at locations far from the housing's liquid inlet/outlet port and high at locations close to the housing's liquid inlet/outlet port. From these results, the following was inferred: Because multiple hollow fiber membranes extend along the pipe's extension direction, in the intermembrane space, the fluid resistance in the pipe's extension direction is likely to be lower than the fluid resistance in the pipe's radial direction. Therefore, it is inferred that a drift occurred in the intermembrane space, where the liquid flowed in the pipe's extension direction rather than the pipe's radial direction, resulting in variations in the liquid flow rate within the housing. Furthermore, even if the liquid flow is reversed, supplying the liquid through the housing's liquid inlet/outlet port and discharging the liquid through the pipe's liquid inlet/outlet port, the liquid passes through the intermembrane space, which is inferred to cause a drift in the intermembrane space and result in variations in the liquid flow rate within the housing. Furthermore, it is presumed that the tensile force of the liquid discharged from the housing liquid supply/discharge port caused the above-mentioned drift to occur more strongly at positions farther from the housing liquid supply/discharge port than at positions closer to the housing liquid supply/discharge port. Based on this, it was discovered that by obstructing the flow of liquid in the direction of extension of the pipe in the intermembrane spaces between multiple hollow fiber membranes, drift of liquid flowing in the direction of extension of the pipe in the intermembrane spaces can be reduced, thereby reducing variation in the liquid flow rate within the housing. The present disclosure is based on the above-mentioned findings.

[1] The degassing module according to the present disclosure comprises a pipe having a plurality of holes formed therein; a hollow fiber membrane bundle in which a plurality of hollow fiber membranes extending along the extension direction of the pipe are bundled together and arranged around the pipe to cover the plurality of holes; a housing that accommodates the pipe and the hollow fiber membrane bundle so that a space is formed between the pipe and the hollow fiber membrane bundle; a partition that divides the area within the housing into an internal area including the hollow portions of each of the plurality of hollow fiber membranes and an external area including the inter-membrane space between the plurality of hollow fiber membranes; and a baffle that is disposed in the inter-membrane space and extends in a direction intersecting the extension direction, wherein the pipe has a pipe inlet/outlet formed at one end that opens to the outside of the housing and a pipe seal that seals the pipe at the other end, and the housing has an air inlet that is connected to the internal area and a housing inlet/outlet that is connected to the external area.

In this degassing module, when liquid is supplied to the pipe through the pipe inlet/outlet, the liquid exits the pipe through the multiple holes, passes through the intermembrane spaces between the hollow fiber membranes, and is discharged through the housing inlet/outlet. When liquid is supplied into the housing through the housing inlet/outlet, the liquid passes through the intermembrane spaces between the hollow fiber membranes, enters the interior of the pipe through the multiple holes in the pipe, and is discharged through the pipe inlet/outlet. The liquid can be degassed by drawing air into the internal area through the air intake. Because the multiple hollow fiber membranes extend along their extension direction, a biased flow of liquid occurs in the intermembrane space, causing the liquid to flow in the extension direction. However, because a baffle extending in a direction intersecting the extension direction is positioned in the intermembrane space, the baffle inhibits the flow of liquid in the extension direction in the intermembrane space. Furthermore, when liquid is supplied to the pipe through the pipe inlet/outlet, the baffle can mitigate the effects of the tensile force of the liquid being discharged from the housing inlet/outlet. This reduces the uneven flow of liquid in the intermembrane space in the extension direction, thereby reducing variations in the flow rate of the liquid within the housing, thereby improving degassing performance.

[2] In the degassing module described in [1] above, the baffle may extend in the circumferential direction of the pipe. In this degassing module, the baffle extends in the circumferential direction, which can effectively obstruct the flow of liquid in the intermembrane space in the extension direction.

[3] In the degassing module described in [2] above, the baffle may extend across the entire intermembrane space in the circumferential direction. In this degassing module, the baffle extends across the entire intermembrane space in the circumferential direction, thereby preventing the flow of liquid in the intermembrane space in the extension direction across the entire circumferential direction.

[4] In the degassing module described in [2] above, the baffle may be provided in a portion of the intermembrane space in the circumferential direction. In this degassing module, the baffle is provided in a portion of the intermembrane space in the circumferential direction. Therefore, by providing the baffle in the circumferential portion where liquid flows easily in the extension direction and not providing the baffle in the circumferential portion where liquid flows less easily in the extension direction, it is possible to effectively obstruct the flow of liquid in the intermembrane space in the extension direction while reducing the material costs of the baffle.

[5] In the degassing module described in [1], [2], or [4] above, the baffle is provided on the housing inlet/outlet side of the pipe as viewed from the extension direction, and does not have to be provided on the opposite side of the pipe from the housing inlet/outlet side as viewed from the extension direction. In the intermembrane space, liquid tends to flow more easily in the extension direction on the housing inlet/outlet side of the pipe as viewed from the extension direction. In this degassing module, the baffle is provided on the housing inlet/outlet side of the pipe as viewed from the extension direction, and is not provided on the opposite side of the pipe from the housing inlet/outlet side as viewed from the extension direction. This effectively obstructs the flow of liquid in the intermembrane space in the extension direction, while reducing the material costs of the baffle.

[6] In the degassing module according to any one of the above [1] to [5], the baffle may extend in a radial direction of the pipe. In this degassing module, since the baffle extends in the radial direction, it is possible to effectively obstruct the flow of liquid in the intermembrane space in the extending direction.
[7] In the degassing module described in [6] above, the baffle may extend across the entire intermembrane space in the radial direction. In this degassing module, since the baffle extends across the entire intermembrane space in the radial direction, it is possible to inhibit the flow of liquid in the intermembrane space in the extending direction across the entire radial direction.

[8] In the degassing module described in [6] above, the baffle may be provided in a portion of the intermembrane space in the radial direction. In this degassing module, the baffle is provided in a portion of the intermembrane space in the radial direction. Therefore, by providing the baffle in the radial portion where liquid flows easily in the extension direction and not providing the baffle in the radial portion where liquid flows less easily in the extension direction, it is possible to effectively obstruct the flow of liquid in the intermembrane space in the extension direction while reducing the material costs of the baffle.

[9] In the degassing module described in any one of [1] to [8] above, the baffle may extend from the pipe to the end of the intermembrane space opposite the pipe. In this degassing module, the baffle extends from the pipe to the end of the intermembrane space opposite the pipe, thereby more effectively inhibiting the flow of liquid in the intermembrane space in the extending direction.

[10] In the degassing module described in any one of [1] to [8] above, the baffle may extend from a position spaced apart from the pipe to the end of the intermembrane space opposite the pipe. In the intermembrane space, the further away from the pipe, the easier it is for liquid to flow in the extension direction. In this degassing module, the baffle extends from a position spaced apart from the pipe to the end of the intermembrane space opposite the pipe, thereby effectively obstructing the flow of liquid in the intermembrane space in the extension direction while reducing the material costs of the baffle.

[11] In the degassing module described in any one of [1] to [10] above, the baffle may extend in a direction inclined relative to the radial direction of the pipe. In this degassing module, because the baffle extends in a direction inclined relative to the radial direction, the flow of liquid obstructed by the baffle can be directed in the direction of the inclination of the baffle. This makes it possible to control the flow of liquid within the housing.

[12] In the degassing module described in any one of [1] to [11] above, the partition includes a first sealing portion that holds one end of the hollow fiber membrane bundle and seals the space between the pipe, the housing, and the plurality of hollow fiber membranes, and a second sealing portion that is positioned on the opposite side of the first sealing portion from the pipe inlet/outlet port in the extension direction and holds the other end of the hollow fiber membrane bundle and seals the space between the pipe, the housing, and the plurality of hollow fiber membranes, and the plurality of holes in the pipe may be formed between the first sealing portion and the second sealing portion in the extension direction. In this degassing module, the first sealing portion and the second sealing portion position the plurality of hollow fiber membranes so that they extend along the extension direction. The first sealing portion and the second sealing portion each seal the space between the pipe, the housing, and the plurality of hollow fiber membranes, and therefore the first sealing portion and the second sealing portion can partition the area within the housing into an internal area and an external area.

[13] In the degassing module described in [12] above, the housing liquid supply/discharge port may be located near the second sealing portion, and the baffle may be located on the pipe liquid supply/discharge port side of the housing liquid supply/discharge port in the extension direction. In this degassing module, because the housing liquid supply/discharge port is located near the second sealing portion, liquid can be brought into contact with multiple hollow fiber membranes over a long range in the extension direction. Furthermore, because the baffle is located on the pipe liquid supply/discharge port side of the housing liquid supply/discharge port in the extension direction, when liquid is supplied to the pipe from the pipe liquid supply/discharge port, the flow of liquid in the extension direction from the pipe liquid supply/discharge port side toward the housing liquid supply/discharge port can be obstructed.

[14] In the degassing module described in [13] above, the baffle may be arranged in a region closer to the housing liquid supply/drain port when the region between the first sealing portion and the housing liquid supply/drain port in the extension direction is divided into two equal parts. In this degassing module, the baffle is arranged in a region closer to the housing liquid supply/drain port when the region between the first sealing portion and the housing liquid supply/drain port in the extension direction is divided into two equal parts. Therefore, when liquid is supplied to a pipe from the pipe liquid supply/drain port, the influence of the pulling force of the liquid discharged from the housing liquid supply/drain port can be mitigated at a position close to the housing liquid supply/drain port. This makes it possible to effectively suppress liquid drift caused by the pulling force of the liquid discharged from the housing liquid supply/drain port.

[15] In the degassing module described in [13] or [14] above, the baffle may be located near the housing liquid supply/drainage port. In this degassing module, the baffle is located near the housing liquid supply/drainage port. Because the baffle is located near the housing liquid supply/drainage port, when liquid is supplied to a pipe from the pipe liquid supply/drainage port, the influence of the pulling force of the liquid discharged from the housing liquid supply/drainage port can be mitigated near the housing liquid supply/drainage port. This makes it possible to more effectively suppress the drift of liquid caused by the pulling force of the liquid discharged from the housing liquid supply/drainage port.

[16] In the degassing module described in any one of [13] to [15] above, the baffle may extend in the extension direction away from the housing liquid supply/discharge port as it moves away from the pipe. In this degassing module, since the baffle extends in the extension direction away from the housing liquid supply/discharge port as it moves away from the pipe, when liquid is supplied to the pipe from the pipe liquid supply/discharge port, the liquid flowing in the extension direction in the intermembrane space can be first directed away from the housing liquid supply/discharge port, and then directed toward the housing liquid supply/discharge port. This allows the contact distance between the liquid and the multiple hollow fiber membranes to be increased.

[17] The degassing module described in any one of [1] to [16] above may further include a second baffle that is positioned in the intermembrane space and extends in a direction intersecting the extension direction, and that is positioned at a different position from the baffle in the extension direction. In this degassing module, the second baffle that is positioned in the intermembrane space and extends in a direction intersecting the extension direction is positioned at a different position from the baffle in the extension direction, so that the flow of liquid in the intermembrane space in the extension direction is also obstructed by the second baffle. This makes it possible to further reduce variation in the flow rate of liquid within the housing.

[18] In the degassing module described in [17] above, the second baffle may be arranged on the pipe supply/discharge port side of the baffle in the extension direction. In this degassing module, since the second baffle is arranged on the pipe supply/discharge port side of the baffle in the extension direction, when liquid is supplied to the pipe from the pipe supply/discharge port, the flow of liquid in the intermembrane space in the extension direction can be obstructed further upstream.

[19] In the degassing module described in [17] or [18] above, the baffle may be arranged on the pipe inlet/outlet side of the housing inlet/outlet in the extension direction, and the second baffle may be arranged on the opposite side of the housing inlet/outlet from the pipe inlet/outlet in the extension direction. In this degassing module, the baffle and the second baffle are arranged to sandwich the housing inlet/outlet in the extension direction. Therefore, when liquid is supplied to the pipe from the pipe inlet/outlet, the flow of liquid in the extension direction from the pipe inlet/outlet side toward the housing inlet/outlet can be inhibited, and the flow of liquid in the extension direction from the opposite side of the pipe inlet/outlet toward the housing inlet/outlet can be inhibited. Furthermore, when liquid is supplied into the housing from the housing inlet/outlet, the flow of liquid in the extension direction from the housing inlet/outlet toward the pipe inlet/outlet side can be inhibited, and the flow of liquid in the extension direction from the housing inlet/outlet toward the opposite side of the pipe inlet/outlet can be inhibited.

[20] A liquid degassing method according to the present disclosure includes a degassing module according to any one of [1] to [19] above, in which the internal region is sucked in through the air inlet, and liquid is supplied to the external region through the pipe inlet or the housing inlet. In this liquid degassing method, the liquid is degassed using any one of the above-described degassing modules, thereby reducing variation in the liquid flow rate within the housing and improving degassing performance.

The present disclosure reduces variations in the liquid flow rate within the housing.

FIG. 2 is a schematic cross-sectional view of a degassing module according to an embodiment. 2 is a schematic cross-sectional view taken along line II-II in FIG. 1. 2 is a schematic cross-sectional view showing an enlarged portion of the degassing module shown in FIG. 1. 2 is a schematic cross-sectional view showing an enlarged portion of the degassing module shown in FIG. 1. 2 is a schematic cross-sectional view showing an enlarged portion of the degassing module shown in FIG. 1. 10A to 10C are schematic cross-sectional views illustrating an example of a method for forming a baffle. FIG. 10 is a schematic cross-sectional view of a degassing module according to a modified example. FIG. 10 is a schematic cross-sectional view of a degassing module according to a modified example. FIG. 10 is a schematic cross-sectional view of a degassing module according to a modified example. FIG. 10 is a schematic cross-sectional view of a degassing module according to a modified example. FIG. 10 is a schematic cross-sectional view of a degassing module according to a modified example. FIG. 10 is a schematic cross-sectional view of a degassing module according to a modified example. FIG. 2 is a schematic cross-sectional view of a degassing module of Comparative Example 1. 1 is a graph showing simulation results for Examples 1 and 2 and Comparative Example 1.

The following describes an embodiment of a degassing module and a liquid degassing method, with reference to the drawings. Note that identical or corresponding parts throughout the drawings are designated by the same reference numerals, and duplicate explanations will be omitted.

Figure 1 is a schematic cross-sectional view of a degassing module according to an embodiment. Figure 2 is a schematic cross-sectional view taken along line II-II in Figure 1. Figures 3 to 5 are schematic cross-sectional views of enlarged portions of the degassing module shown in Figure 1. As shown in Figures 1 to 5, the degassing module 1 according to an embodiment is a module for degassing a liquid L. The liquid L degassed by the degassing module 1 is not particularly limited, but may be, for example, seawater, drinking water, pure water, ultrapure water, or other water, an aqueous solution containing ammonium sulfate, a surfactant, or the like, an organic solvent such as alcohol or hydrocarbon, or an ionic liquid.

The degassing module 1 comprises a pipe 2, a hollow fiber membrane bundle 3, a housing 4, a partition 5, and a baffle 6.

The pipe 2 is a cylindrical member that extends linearly along the central axis A. The direction in which the pipe 2 extends cylindrically, i.e., the direction in which the central axis A of the pipe 2 extends, is referred to as the extension direction D1 of the pipe 2, or simply as the extension direction D1. The circumferential direction of the pipe 2, i.e., the direction around the central axis A, is referred to as the circumferential direction D2 of the pipe 2, or simply as the circumferential direction D2. The radial direction of the pipe 2, with the central axis A as the base point, is referred to as the radial direction D3 of the pipe 2, or simply as the radial direction D3.

The pipe 2 forms an internal pipe flow path 21. The internal pipe flow path 21 is a flow path through which liquid L can flow, and is formed by the inner circumferential surface of the pipe 2. One end of the pipe 2 in the extension direction D1 is referred to as the first end 2a, and the other end of the pipe 2 in the extension direction D1 is referred to as the second end 2b. The pipe 2 has a pipe supply/discharge port 22 formed at the first end 2a, and a pipe sealing portion 23 that seals the pipe 2 at the second end 2b. In other words, at the first end 2a, the internal pipe flow path 21 is open by the pipe supply/discharge port 22, and at the second end 2b, the internal pipe flow path 21 is sealed by the pipe sealing portion 23.

A plurality of holes 24 are formed in the pipe 2. The plurality of holes 24 are holes for allowing the liquid L to flow from the internal pipe flow path 21 to the outside of the pipe 2. The plurality of holes 24 are formed in the peripheral wall of the pipe 2 and open the internal pipe flow path 21 to the outside of the pipe 2.

The pipe 2 has a hole-forming portion 25 and a non-hole-forming portion 26. The hole-forming portion 25 is a portion where multiple holes 24 are formed. The non-hole-forming portion 26 is a portion where multiple holes 24 are not formed. The non-hole-forming portion 26 extends in the extension direction D1 from the first end 2a, where the pipe internal flow path 21 is opened by the pipe supply/discharge port 22, toward the second end 2b. The hole-forming portion 25 extends in the extension direction D1 from the non-hole-forming portion 26 to the second end 2b, where the pipe internal flow path 21 is sealed by the pipe sealing portion 23.

The inner and outer diameters of the hole-forming portion 25 and the non-hole-forming portion 26 are not particularly limited. For example, from the perspective of increasing the total area of the multiple holes 24, the inner and outer diameters of the hole-forming portion 25 may be larger than the inner and outer diameters of the non-hole-forming portion 26. For example, the hole-forming portion 25 and the non-hole-forming portion 26 may be separate members, and the pipe 2 may be constructed by inserting the small-diameter non-hole-forming portion 26 into the end of the large-diameter hole-forming portion 25.

The hollow fiber membrane bundle 3 is formed by bundling multiple hollow fiber membranes 31 extending along the extension direction D1. The hollow fiber membrane bundle 3 is arranged around the pipe 2 so as to cover the multiple holes 24. The hollow fiber membrane bundle 3 is formed in a roughly cylindrical shape and extends along the extension direction D1. That is, multiple hollow fiber membranes 31 extending along the extension direction D1 are bundled together so that the hollow fiber membrane bundle 3 has a roughly cylindrical shape. One end of the hollow fiber membrane bundle 3 in the extension direction D1 is referred to as the first end 3a, and the other end of the hollow fiber membrane bundle 3 in the extension direction D1 is referred to as the second end 3b. The first end 3a is the end on the pipe inlet/outlet port 22 side in the extension direction D1. The second end 3b is the end on the opposite side of the pipe inlet/outlet port 22 in the extension direction D1.

Each of the multiple hollow fiber membranes 31 is a hollow fiber membrane that allows gas G to pass through but not liquid L to pass through. The material, shape, and configuration of each of the multiple hollow fiber membranes 31 are not particularly limited. Examples of materials for each of the multiple hollow fiber membranes 31 include polyolefin resins such as polypropylene, polyethylene, and polymethylpentene; silicone resins such as polydimethylsiloxane and its copolymers; and fluorine-based resins such as PTFE and vinylidene fluoride. Examples of the configuration (sidewall shape) of each of the multiple hollow fiber membranes 31 include porous membranes, microporous membranes, and homogeneous membranes (non-porous membranes) that do not have porosity. Examples of the configuration of each of the multiple hollow fiber membranes 31 include symmetric membranes (homogeneous membranes) in which the entire membrane has a homogeneous chemical or physical structure, and asymmetric membranes (heterogeneous membranes) in which the chemical or physical structure of each membrane varies depending on the membrane. An asymmetric membrane (heterogeneous membrane) is a membrane that has a non-porous dense layer and a porous layer. In this case, the dense layer may be formed anywhere in the membrane, such as on the surface of the membrane or inside the porous membrane. Heterogeneous membranes also include composite membranes with different chemical structures and multilayer membranes such as three-layer structures. In particular, heterogeneous membranes using poly(4-methylpentene-1) resin are particularly preferred because they have a dense layer that blocks liquid L.

The outer diameter of each of the multiple hollow fiber membranes 31 is not particularly limited. From the perspective of increasing the membrane area, the outer diameter of each of the multiple hollow fiber membranes 31 can be, for example, 500 μm or less, preferably 350 μm or less, and more preferably 250 μm or less. On the other hand, from the perspective of suppressing breakage, the outer diameter of each of the multiple hollow fiber membranes 31 can be, for example, 50 μm or more, preferably 150 μm or more, and more preferably 200 μm or more.

The hollow fiber membrane bundle 3 is positioned on the outer periphery of the hole-formed portion 25 of the pipe 2, but is not positioned on the outer periphery of the non-hole-formed portion 26 of the pipe 2. The hollow fiber membrane bundle 3 is formed in a generally cylindrical shape so as to surround the hole-formed portion 25. The hollow fiber membrane bundle 3 is formed, for example, from a hollow fiber membrane fabric 8 (see Figure 6) woven in the shape of a bamboo blind. The hollow fiber membrane fabric 8 is a fabric woven from multiple hollow fiber membranes 31 that serve as weft yarns and warp yarns 9. In the hollow fiber membrane fabric 8, multiple hollow fiber membranes 31 are arranged in the shape of a bamboo blind. The hollow fiber membrane bundle 3 is formed by wrapping the hollow fiber membrane fabric 8 around the hole-formed portion 25 so that the multiple hollow fiber membranes 31 extend in the extension direction D1.

In the hollow fiber membrane bundle 3, an intermembrane space S1 is formed between the multiple hollow fiber membranes 31 (between adjacent hollow fiber membranes 31). The intermembrane space S1 is a space through which liquid L can flow. The intermembrane space S1 is also formed between the multiple hollow fiber membranes 31 in the circumferential direction D2 of the pipe 2, and also between the multiple hollow fiber membranes 31 in the radial direction D3 of the pipe 2.

The housing 4 accommodates the pipe 2 and the hollow fiber membrane bundle 3 so that a space S2 is formed between the hollow fiber membrane bundle 3 and the housing 4. The space S2 is a space between the hollow fiber membrane bundle 3 and the housing 4 through which liquid L can flow. The housing 4 is formed in a cylindrical shape extending in the extension direction D1. The first end 2a of the pipe 2, where the pipe supply/discharge port 22 is formed, protrudes from the housing 4, and the pipe supply/discharge port 22 is open to the outside of the housing 4. Note that the first end 2a of the pipe 2 does not necessarily have to protrude from the housing 4, but in this embodiment, the first end 2a of the pipe 2 protrudes from the housing 4 from the perspective of facilitating connection of other components to the pipe 2.

The partition 5 separates the area within the housing 4 into an internal area R1 and an external area R2. The internal area R1 is an area that includes the hollow portions 32 of each of the multiple hollow fiber membranes 31. The external area R2 is an area that includes the intermembrane spaces S1 between the multiple hollow fiber membranes 31. Therefore, each of the multiple hollow fiber membranes 31 forms a boundary between the internal area R1 and the external area R2. Each of the multiple hollow fiber membranes 31 prevents the passage of liquid L from the external area R2 to the internal area R1, and allows the passage of gas G (such as dissolved gas in the liquid L or air bubbles contained in the liquid L) from the external area R2 to the internal area R1.

The partition 5 has a first sealing portion 51 and a second sealing portion 52. The first sealing portion 51 holds the first end portion 3a of the hollow fiber membrane bundle 3, sealing the space between the pipe 2, the housing 4, and the plurality of hollow fiber membranes 31. The first end portion 3a of the hollow fiber membrane bundle 3 is fixed to the outer surface of the pipe 2 and the inner surface of the housing 4 by the first sealing portion 51. The second sealing portion 52 holds the second end portion 3b of the hollow fiber membrane bundle 3, sealing the space between the pipe 2, the housing 4, and the plurality of hollow fiber membranes 31. The second end portion 3b of the hollow fiber membrane bundle 3 is fixed to the outer surface of the pipe 2 and the inner surface of the housing 4 by the second sealing portion 52. The first sealing portion 51 and the second sealing portion 52 are formed, for example, from a resin. Examples of resins used for the first sealing portion 51 and the second sealing portion 52 include epoxy resin, urethane resin, ultraviolet-curing resin, and polyolefin resins such as polyethylene and polypropylene.

In a cross section perpendicular to the extension direction D1, the first sealing portion 51 and the second sealing portion 52 each fill the entire area between the pipe 2 and the housing 4 except for the multiple hollow fiber membranes 31. In other words, in a cross section perpendicular to the extension direction D1, the first sealing portion 51 and the second sealing portion 52 each fill the area between the pipe 2 and the hollow fiber membrane bundle 3, between the multiple hollow fiber membranes 31 (inter-membrane space S1), and between the hollow fiber membrane bundle 3 and the housing 4 (space S2). The hollow portion 32 of each of the multiple hollow fiber membranes 31 is open from the first sealing portion 51 to the side opposite the second sealing portion 52, and is also open from the second sealing portion 52 to the side opposite the first sealing portion 51.

The first sealing portion 51 is disposed between the hole-forming portion 25 and the non-hole-forming portion 26 in the extension direction D1. The second sealing portion 52 is disposed at the end of the hole-forming portion 25 opposite the non-hole-forming portion 26 in the extension direction D1. In other words, the multiple holes 24 in the pipe 2 are formed between the first sealing portion 51 and the second sealing portion 52 in the extension direction D1. Therefore, the region between the pipe 2 and the housing 4 on the side opposite the second sealing portion 52 of the first sealing portion 51 is the internal region R1. Furthermore, the region within the housing 4 on the side opposite the second sealing portion 52 of the first sealing portion 51 is the internal region R1. The region of the internal region R1 on the side opposite the second sealing portion 52 of the first sealing portion 51 is referred to as the first internal region S3. Furthermore, the region of the internal region R1 on the side opposite the second sealing portion 52 of the first sealing portion 51 is referred to as the second internal region S4. On the other hand, the inter-membrane spaces S1 between the plurality of hollow fiber membranes 31 between the first sealing portion 51 and the second sealing portion 52 and the space S2 between the housing 4 and the hollow fiber membrane bundle 3 form the outer region R2.

The housing 4 is formed with a first air intake port 41, a second air intake port 42, and a housing liquid supply/drain port 43.

The first air intake port 41 and the second air intake port 42 are openings for drawing air from the internal region R1. The first air intake port 41 is formed on the opposite side of the first sealing portion 51 from the second sealing portion 52 in the extension direction D1. The first air intake port 41 is connected to the internal region R1 located on the opposite side of the first sealing portion 51 from the second sealing portion 52. The second air intake port 42 is formed on the opposite side of the second sealing portion 52 from the first sealing portion 51 in the extension direction D1. The second air intake port 42 is connected to the internal region R1 located on the opposite side of the second sealing portion 52 from the first sealing portion 51. A suction device (not shown), such as a vacuum pump, is connected to the first air intake port 41 and the second air intake port 42.

The housing supply/drain port 43 is an opening that opens the external region R2 to the outside of the housing 4. The housing supply/drain port 43 is formed between the first sealing portion 51 and the second sealing portion 52 in the extension direction D1. The housing supply/drain port 43 is connected to the space S2, which is the external region R2 and is located between the first sealing portion 51 and the second sealing portion 52.

The position of the housing supply/drain port 43 in the extension direction D1 is not particularly limited, but in this embodiment, the housing supply/drain port 43 is located near the second sealing portion 52 in order to increase the distance between the pipe supply/drain port 22 and the housing supply/drain port 43 in the extension direction D1.

The housing 4 comprises a cylindrical body 4a, a first lid portion 4b, and a second lid portion 4c.

The cylindrical body 4a houses the hollow fiber membrane bundle 3. The cylindrical body 4a extends in the extension direction D1 and is cylindrically shaped with both ends open. The first sealing portion 51 is located at one open end of the cylindrical body 4a in the extension direction D1, and the second sealing portion 52 is located at the other open end of the cylindrical body 4a in the extension direction D1. That is, the first end 3a of the hollow fiber membrane bundle 3 is fixed to one open end of the cylindrical body 4a by the first sealing portion 51, and the second end 3b of the hollow fiber membrane bundle 3 is fixed to the other open end of the cylindrical body 4a by the second sealing portion 52. An external region R2 is formed within the cylindrical body 4a, and the housing liquid supply/discharge port 43 is formed in the side wall of the cylindrical body 4a and is connected to the external region R2.

The first lid portion 4b is a portion that forms the first internal region S3 (internal region R1). The first lid portion 4b is cylindrical, extending in the extension direction D1 and having one open end and the other closed end. The first lid portion 4b covers the side of the first sealing portion 51 opposite the second sealing portion 52 and is attached to one open end of the cylindrical body 4a so as to surround the first sealing portion 51 from the outside of the cylindrical body 4a. Therefore, by attaching the first lid portion 4b to the cylindrical body 4a, the first internal region S3 is formed inside the first lid portion 4b. The first air intake 41 is formed in the side wall of the first lid portion 4b and is connected to the first internal region S3 (internal region R1). The pipe 2 penetrates the first lid portion 4b, and the first lid portion 4b is attached to the outer surface of the pipe 2 so as to maintain an airtight seal between the first lid portion 4b and the pipe 2.

The second lid portion 4c is a portion that forms the second internal region S4 (internal region R1). The second lid portion 4c is cylindrical, extending in the extension direction D1 and having one open end and the other closed end. The second lid portion 4c covers the side of the second sealing portion 52 opposite the first sealing portion 51 and is attached to the open end of the other side of the cylindrical body 4a so as to surround the second sealing portion 52 from the outside of the cylindrical body 4a. Therefore, by attaching the second lid portion 4c to the cylindrical body 4a, the second internal region S4 is formed inside the second lid portion 4c. The second air intake 42 is formed in the side wall of the second lid portion 4c and is connected to the second internal region S4 (internal region R1). A pipe sealing portion 23 abuts against the inner surface of the second lid portion 4c.

The baffle 6 is intended to inhibit the flow of liquid L in the intermembrane space S1 in the extension direction D1. Because the multiple hollow fiber membranes 31 extend along the extension direction D1, the fluid resistance in the intermembrane space S1 is likely to be smaller in the extension direction D1 than in the radial direction D3. Therefore, in the intermembrane space S1, a biased flow occurs in which the liquid L flows in the extension direction D1 rather than the radial direction D3. Such a biased flow in the intermembrane space S1 is likely to cause variations in the flow rate of the liquid L within the housing 4. Therefore, the baffle 6 inhibits the flow of the liquid L in the extension direction D1 in the intermembrane space S1, thereby reducing the biased flow of the liquid L in the extension direction D1 in the intermembrane space S1. The baffle 6 does not need to inhibit all of the flow of the liquid L in the extension direction D1 in the intermembrane space S1; it is sufficient if it can inhibit at least a portion of the flow of the liquid L in the extension direction D1 in the intermembrane space S1.

The baffle 6 is disposed between the first sealed portion 51 and the second sealed portion 52 in the extension direction D1. The baffle 6 is disposed in the intermembrane space S1 and extends in a direction intersecting the extension direction D1. In this embodiment, the baffle 6 is provided in the entire area, excluding the plurality of hollow fiber membranes 31, from the pipe 2 to the end of the intermembrane space S1 opposite the pipe 2 in a cross section perpendicular to the extension direction D1. More specifically, the baffle 6 extends in the circumferential direction D2 and radial direction D3 of the pipe 2. In other words, the baffle 6 extends in a direction perpendicular to the extension direction D1. The baffle 6 also extends across the entire intermembrane space S1 in the circumferential direction D2 of the pipe 2. The baffle 6 also extends across the entire intermembrane space S1 in the radial direction D3 of the pipe 2. The baffle 6 also extends from the pipe 2 to the end of the intermembrane space S1 opposite the pipe 2. The end of the intermembrane space S1 opposite the pipe 2 refers to, for example, the end of the intermembrane space S1 opposite the pipe 2 in the radial direction D3. Note that a space S2 is formed between the baffle 6 and the housing 4, but the baffle 6 may protrude beyond the intermembrane space S1 into the space S2 as long as the space S2 is not closed by the baffle 6.

The thickness of the baffle 6 in the extension direction D1 is not particularly limited. From the perspective of increasing the contact area between the liquid L and the multiple hollow fiber membranes 31, it is preferable that the thickness of the baffle 6 in the extension direction D1 be as thin as possible while still maintaining the rigidity of the baffle 6.

The position of the baffle 6 in the extension direction D1 is not particularly limited. For example, the baffle 6 can be positioned in the area on the housing supply/drain port 43 side when the area between the first sealing portion 51 and the housing supply/drain port 43 in the extension direction D1 is divided into two, three, or four equal parts. In this embodiment, the baffle 6 is positioned near the housing supply/drain port 43 on the pipe supply/drain port 22 side of the housing supply/drain port 43 in the extension direction D1.

The baffle 6 is formed, for example, from a resin. Examples of resins that can be used for the baffle 6 include urethane-based resins such as polyurethane (PU) and thermoplastic polyurethane (TPU); polycarbonate (PC); vinyl chloride-based resins such as polyvinyl chloride (PVC) and vinyl chloride-vinyl acetate copolymer resin; acrylic resins such as polyacrylic acid, polymethacrylic acid, polymethyl acrylate, polymethyl methacrylate (PMMA), and polyethyl methacrylate; polyester-based resins such as polyethylene terephthalate (PET), polybutylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate; polyamide-based resins such as nylon (registered trademark); polystyrene (PS), imide-modified polystyrene, acrylonitrile butadiene styrene (ABS) resin, and imide-modified ABS resin. Examples of suitable thermosetting resins include polystyrene-based resins such as styrene-acrylonitrile copolymer (SAN) resin and acrylonitrile-ethylene-propylene-diene-styrene (AES) resin; olefin-based resins such as polyethylene (PE) resin, polypropylene (PP) resin, polymethylpentene (PMP) resin, and cycloolefin resin; cellulose-based resins such as nitrocellulose and cellulose acetate; silicone-based resins; fluorine-based resins; thermoplastic resins such as polyphenylene ether (PPE) resin; epoxy (EPOXY)-based resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, isocyanurate epoxy resin, and hydantoin epoxy resin; amino-based resins such as melamine resin and urea resin; phenol-based resins; and unsaturated polyester-based resins. Of these, PP, PE, PVC, EPOXY, PMP, and PU are preferred.

Figure 6 is a schematic cross-sectional view illustrating an example of a baffle formation method. As shown in Figure 6, when forming the baffle 6, first, a hollow fiber membrane fabric 8 is wrapped around the pipe 2 so as to cover the multiple holes 24 in the pipe 2. As described above, the hollow fiber membrane fabric 8 is a fabric in which multiple hollow fiber membranes 31, which serve as weft threads, are woven with warp threads 9. If the surface of the hollow fiber membrane fabric 8 that is wrapped around the pipe 2 is the inner fabric surface 8a, molten resin 10 is applied to the position of the inner fabric surface 8a corresponding to the baffle 6. The hollow fiber membrane fabric 8 to which the molten resin 10 has been applied is then wrapped around the pipe 2. The molten resin 10 then impregnates the inner layer hollow fiber membrane fabric 8 and the outer layer hollow fiber membrane fabric 8, filling the positions corresponding to the baffle 6. The molten resin 10 then hardens to form the baffle 6.

Next, we will explain the method for degassing liquid L using degassing module 1.

Air is drawn into the internal region R1 through the first air intake port 41 and the second air intake port 42, and liquid L is supplied to the external region R2 through the pipe liquid supply/discharge port 22. Air can be drawn into the internal region R1 through the first air intake port 41 and the second air intake port 42, for example, by connecting a suction device (not shown) such as a vacuum pump to the first air intake port 41 and the second air intake port 42 and operating this suction device. By drawing air into the internal region R1 through the first air intake port 41 and the second air intake port 42, the internal region R1, including the hollow portions 32 of each of the multiple hollow fiber membranes 31, is depressurized.

The liquid L is then supplied from the pipe inlet/outlet port 22 to the pipe flow path 21, exits the pipe 2 through the multiple holes 24, and is supplied to the intermembrane space S1. At this time, the hollow portion 32 of each of the multiple hollow fiber membranes 31 is depressurized, so gas G, such as dissolved gas in the liquid L and bubbles contained in the liquid L, passes through each of the multiple hollow fiber membranes 31. This degasses the liquid L. The liquid L exiting the multiple holes 24 flows not only in the radial direction D3 through the intermembrane space S1, but also in the extension direction D1 through the intermembrane space S1. The flow of the liquid L in the extension direction D1 through the intermembrane space S1 is obstructed by the baffle 6, so it reaches the space S2 on the pipe inlet/outlet port 22 side of the baffle 6 in the extension direction D1. The liquid L degassed in the intermembrane space S1 passes through the space S2 and is discharged to the outside of the degassing module 1 through the housing liquid supply/discharge port 43.

In this manner, in the degassing module 1 according to this embodiment, when liquid L is supplied to the pipe 2 through the pipe inlet/outlet port 22, the liquid L exits the pipe 2 through the multiple holes 24, passes through the intermembrane space S1 between the multiple hollow fiber membranes 31, and is discharged from the housing inlet/outlet port 43. At this time, the liquid L can be degassed by suctioning the internal region R1 through the first air inlet 41 and the second air inlet 42. Because the multiple hollow fiber membranes 31 extend along the extension direction D1, a biased flow of the liquid L in the intermembrane space S1 occurs. However, because the baffle 6 extending in a direction intersecting the extension direction D1 is disposed in the intermembrane space S1, the flow of the liquid L in the extension direction D1 in the intermembrane space S1 is obstructed by the baffle 6. Furthermore, the baffle 6 can mitigate the effects of the tensile force of the liquid L being discharged from the housing inlet/outlet port 43. This reduces the uneven flow of the liquid L in the extending direction D1 in the intermembrane space S1, thereby reducing the variation in the flow rate of the liquid L within the housing 4. As a result, the degassing performance can be improved.

In addition, in this degassing module 1, the baffle 6 extends in the circumferential direction D2, thereby effectively obstructing the flow of liquid L in the intermembrane space S1 in the extension direction D1.

In addition, in this degassing module 1, the baffle 6 extends throughout the entire intermembrane space S1 in the circumferential direction D2, thereby preventing the flow of liquid L in the intermembrane space S1 in the extension direction D1 throughout the entire circumferential direction D2.

In addition, in this degassing module 1, the baffle 6 extends in the radial direction D3, thereby effectively obstructing the flow of liquid L in the intermembrane space S1 in the extension direction D1.

In addition, in this degassing module 1, the baffle 6 extends throughout the entire intermembrane space S1 in the radial direction D3, thereby preventing the flow of liquid L in the intermembrane space S1 in the extension direction D1 throughout the entire radial direction D3.

In addition, in this degassing module 1, the baffle 6 extends from the pipe 2 to the end of the intermembrane space S1 opposite the pipe 2 in the radial direction D3, thereby more effectively inhibiting the flow of liquid L in the intermembrane space S1 in the extension direction D1.

In addition, in this degassing module 1, the first sealing portion 51 and the second sealing portion 52 arrange the multiple hollow fiber membranes 31 so that they extend along the extension direction D1. The first sealing portion 51 and the second sealing portion 52 each seal the space between the pipe 2, the housing 4, and the multiple hollow fiber membranes 31, so that the first sealing portion 51 and the second sealing portion 52 can divide the area within the housing 4 into an inner region R1 and an outer region R2.

In addition, in this degassing module 1, the housing liquid supply/discharge port 43 is located near the second sealing portion 52, allowing the liquid L to come into contact with the multiple hollow fiber membranes 31 over a long range in the extension direction D1. The baffle 6 is positioned on the pipe liquid supply/discharge port 22 side of the housing liquid supply/discharge port 43 in the extension direction D1. Therefore, the flow of the liquid L in the intermembrane space S1 in the extension direction D1 can be obstructed between the pipe liquid supply/discharge port 22 and the housing liquid supply/discharge port 43 in the extension direction D1.

In addition, in this degassing module 1, the baffle 6 is positioned in the area on the housing liquid supply/drainage port 43 side when the area between the first sealing portion 51 and the housing liquid supply/drainage port 43 in the extension direction D1 is divided into two equal parts, so the influence of the pulling force of the liquid L discharged from the housing liquid supply/drainage port 43 can be alleviated at a position close to the housing liquid supply/drainage port 43. This makes it possible to effectively suppress the drift of the liquid L caused by the pulling force of the liquid L discharged from the housing liquid supply/drainage port 43.

In addition, in this degassing module 1, the baffle 6 is positioned near the housing liquid supply/drainage port 43 in the extension direction D1, so the influence of the pulling force of the liquid L discharged from the housing liquid supply/drainage port 43 can be alleviated near the housing liquid supply/drainage port 43. This makes it possible to more effectively suppress the drift of the liquid L caused by the pulling force of the liquid L discharged from the housing liquid supply/drainage port 43.

In the liquid degassing method of this embodiment, the liquid L is degassed using the above-mentioned degassing module 1, thereby reducing the variation in the flow rate of the liquid L within the housing 4 and improving degassing performance.

The above describes a preferred embodiment of the present disclosure, but the present disclosure is not limited to the above embodiment.

For example, in the above embodiment, the baffles were described as extending across the entire intermembrane space in the radial direction of the pipe, but as in the degassing module 1A shown in Figure 7, the baffles may be provided in only a portion of the intermembrane space in the radial direction of the pipe. When baffles are provided in only a portion of the intermembrane space in the radial direction of the pipe, by providing the baffles in the radial portion where liquid flows easily in the extension direction and not providing the baffles in the radial portion where liquid does not flow easily in the extension direction, it is possible to effectively obstruct the flow of liquid in the intermembrane space in the extension direction while reducing the material costs of the baffles.

Figure 7 is a schematic cross-sectional view of a modified degassing module. The degassing module 1A shown in Figure 7 is basically the same as the degassing module 1 of the above embodiment, except that a baffle 6A corresponding to the baffle 6 of the degassing module 1 extends from a position spaced apart from the pipe 2 to the end of the intermembrane space S1 opposite the pipe 2. In other words, the pipe 2 and the baffle 6A are spaced apart, allowing liquid L to flow between the pipe 2 and the baffle 6A. Note that the baffle 6A may be divided into multiple pieces in the radial direction D3, and may not extend to the end of the intermembrane space S1 opposite the pipe 2 in the radial direction D3.

In the intermembrane space S1, the liquid L tends to flow more easily in the extension direction D1 the further away from the pipe 2. In this degassing module 1A, the baffle 6A extends from a position away from the pipe 2 to the end of the intermembrane space S1 opposite the pipe 2, thereby effectively obstructing the flow of the liquid L in the intermembrane space S1 in the extension direction D1 while reducing the material cost of the baffle 6A.

In addition, for example, in the above embodiment, the baffles were described as extending over the entire circumferential area of the pipe, but as in the degassing module 1B shown in Figure 8, the baffles may be provided only on a portion of the circumferential area of the pipe. When the baffles are provided in a portion of the intermembrane space in the circumferential direction, the baffles can be provided in the circumferential portion where the liquid flows easily in the extension direction, and not in the circumferential portion where the liquid flows less easily, thereby effectively obstructing the flow of liquid in the intermembrane space in the extension direction while reducing the material costs of the baffles.

Figure 8 is a schematic cross-sectional view of a modified degassing module. The degassing module 1B shown in Figure 8 is basically the same as the degassing module 1 of the above embodiment, except that a baffle 6B corresponding to the baffle 6 of the degassing module 1 is provided on the housing inlet/outlet port 43 side of the pipe 2 when viewed from the direction along the central axis A (extension direction D1) (see Figure 2), but is not provided on the opposite side of the housing inlet/outlet port 43 of the pipe 2. For example, when the inter-membrane space S1 is divided by a line perpendicular to the line passing through the central axis A and the housing inlet/outlet port 43 when viewed from the direction along the central axis A (extension direction D1) (see Figure 2), the baffle 6B is provided in the area on the housing inlet/outlet port 43 side, but not in the area opposite the housing inlet/outlet port 43. Note that the baffle 6B may be divided into multiple parts in the circumferential direction D2.

In the intermembrane space S1, liquid L tends to flow in the extension direction D1 on the side of the housing liquid supply/drainage port 43 of the pipe 2 as viewed from the extension direction D1. In this degassing module 1B, the baffle 6B is provided on the side of the housing liquid supply/drainage port 43 of the pipe 2 as viewed from the extension direction D1, and is not provided on the opposite side of the housing liquid supply/drainage port 43 of the pipe 2 as viewed from the extension direction D1. This effectively obstructs the flow of liquid L in the intermembrane space S1 in the extension direction D1 while reducing the material cost of the baffle 6B.

Also, for example, in the above embodiment, the baffles were described as extending in a direction perpendicular to the extension direction of the pipe, but the baffles may also extend in a direction inclined relative to the radial direction of the pipe, as in the degassing module 1C shown in Figure 9.

Figure 9 is a schematic cross-sectional view of a modified degassing module. The degassing module 1C shown in Figure 9 is basically the same as the degassing module 1 of the above embodiment, but the baffle 6C, which corresponds to the baffle 6 of the degassing module 1, extends in a direction inclined with respect to the radial direction D3 and extends in a direction away from the housing liquid supply/drainage port 43 in the extension direction D1 as it moves away from the pipe 2. In other words, the baffle 6C is positioned so as to prevent the liquid L in the intermembrane space S1 from moving toward the housing liquid supply/drainage port 43.

In this way, in this degassing module 1C, the baffles 6C extend in a direction inclined relative to the radial direction D3, so the flow of liquid L that is obstructed by the baffles 6C can be directed in the direction of the inclination of the baffles 6C. This makes it possible to control the flow of liquid L within the housing 4.

Furthermore, in this degassing module 1C, the baffle 6C extends in the extension direction D1 away from the housing liquid supply/discharge port 43 as it moves away from the pipe 2, so that the liquid L flowing in the extension direction D1 in the intermembrane space S1 can be directed first away from the housing liquid supply/discharge port 43 and then toward the housing liquid supply/discharge port 43. This increases the contact distance between the liquid L and the multiple hollow fiber membranes 31.

Furthermore, for example, in the above embodiment, the degassing module was described as having one baffle, but the degassing module may also have multiple baffles, such as degassing module 1D shown in Figure 10 and degassing module 1E shown in Figure 11.

Figure 10 is a schematic cross-sectional view of a modified degassing module. The degassing module 1D shown in Figure 10 is basically the same as the degassing module 1 of the above embodiment, but in addition to baffle 6, it includes a second baffle 7. Like baffle 6, second baffle 7 is disposed in the intermembrane space S1 and extends in a direction intersecting the extension direction D1. The configuration, shape, etc. of second baffle 7 may be the same as or different from that of baffle 6. The second baffle 7 is disposed at a different position in the extension direction D1 from that of baffle 6. Specifically, the second baffle 7 is disposed on the pipe supply/drain port 22 side of baffle 6 in the extension direction D1, that is, on the opposite side of the housing supply/drain port 43 of baffle 6 in the extension direction D1.

In this way, in this degassing module 1D, the second baffle 7, which is disposed in the intermembrane space S1 and extends in a direction intersecting the extension direction D1, is positioned at a different position in the extension direction D1 from the baffle 6, so that the flow of the liquid L in the intermembrane space S1 in the extension direction is also obstructed by the second baffle 7. This further reduces the variation in the flow rate of the liquid L within the housing 4.

Furthermore, in this degassing module 1D, the second baffle 7 is positioned on the pipe supply/discharge port 22 side of the baffle 6 in the extension direction D1, so that the flow of liquid L in the intermembrane space S1 in the extension direction D1 can be obstructed further upstream.

Figure 11 is a schematic cross-sectional view of a modified degassing module. The degassing module 1E shown in Figure 11 is basically the same as the degassing module 1 of the above embodiment, but in addition to the baffle 6, it includes a second baffle 7, and the housing inlet/outlet 43 is formed in the center between the first sealing portion 51 and the second sealing portion 52 in the extension direction D1. Like the degassing module 1 of the above embodiment, the baffle 6 is located near the housing inlet/outlet 43 on the pipe inlet/outlet 22 side of the housing inlet/outlet 43 in the extension direction D1. Like the baffle 6, the second baffle 7 is located in the inter-membrane space S1 and extends in a direction intersecting the extension direction D1. The configuration, shape, etc. of the second baffle 7 may be the same as or different from the baffle 6. The second baffle 7 is located at a different position in the extension direction D1 from the baffle 6. Specifically, the second baffle 7 is disposed near the housing liquid supply/drain port 43 on the opposite side of the housing liquid supply/drain port 43 from the pipe liquid supply/drain port 22 in the extension direction D1.

In this way, in this degassing module 1E, the second baffle 7, which is disposed in the intermembrane space S1 and extends in a direction intersecting the extension direction D1, is disposed at a different position in the extension direction D1 from the baffle 6. Therefore, the flow of the liquid L in the intermembrane space S1 in the extension direction is also obstructed by the second baffle 7. This further reduces the variation in the flow rate of the liquid L within the housing 4.

Furthermore, in this degassing module 1E, the baffle 6 is positioned on the pipe inlet/outlet 22 side of the housing inlet/outlet 43 in the extension direction D1, and the second baffle 7 is positioned on the opposite side of the housing inlet/outlet 43 from the pipe inlet/outlet 22 in the extension direction D1. In other words, the baffle 6 and the second baffle 7 are positioned to sandwich the housing inlet/outlet 43 in the extension direction D1. This makes it possible to inhibit the flow of liquid L from the pipe inlet/outlet 22 side toward the housing inlet/outlet 43 in the extension direction D1, and also to inhibit the flow of liquid L from the opposite side of the pipe inlet/outlet 22 toward the housing inlet/outlet 43 in the extension direction D1. Moreover, in this degassing module 1E, the housing inlet/outlet 43 is formed in the center between the first sealing portion 51 and the second sealing portion 52, thereby achieving a high effect.

Furthermore, in the above embodiment, two air intakes are described as being formed in the housing, but the housing may also have only one air intake.

For example, in the above embodiment, a method of degassing a liquid was described in which the liquid was supplied to an external area from a pipe supply/drain port, but a method of supplying the liquid to an external area from a housing supply/drain port may also be used.

Figure 12 is a schematic cross-sectional view of a modified degassing module. The degassing module shown in Figure 12 is identical to the degassing module shown in Figure 1, except for the liquid flow. As shown in Figure 12, in this method, the internal region R1 is suctioned through the first and second air intakes 41 and 42, and liquid L is supplied to the external region R2 through the housing liquid supply/discharge port 43. Liquid L is then supplied from the housing liquid supply/discharge port 43 through space S2 to the intermembrane space S1. At this time, the hollow portions 32 of the multiple hollow fiber membranes 31 are in a depressurized state, so dissolved gases in the liquid L and gases G, such as air bubbles contained in the liquid L, pass through each of the multiple hollow fiber membranes 31. This degasses the liquid L. Here, the liquid L supplied from the housing liquid supply/discharge port 43 through space S2 to the intermembrane space S1 flows not only in the direction opposite to the radial direction D3 through the intermembrane space S1, but also in the extension direction D1 through the intermembrane space S1. The liquid L flowing in the intermembrane space S1 in the extension direction D1 is obstructed by the baffle 6, and reaches the pipe 2 on the housing liquid supply/discharge port 43 side of the baffle 6 in the extension direction D1. The liquid L degassed in the intermembrane space S1 is then supplied to the pipe flow path 21 through the multiple holes 24 in the pipe 2 and discharged to the outside of the degassing module 1 through the pipe liquid supply/discharge port 22. In this case, too, the position, shape, number, etc. of the baffles are not particularly limited and can be, for example, similar to the above-mentioned modified example.

Next, examples of the present disclosure will be described, but the present disclosure is not limited to the following examples.

(Examples 1 and 2 and Comparative Example 1)
The degassing module 1 shown in Fig. 1 was used as the simulation model for Example 1. The degassing module 1D shown in Fig. 10 was used as the simulation model for Example 2. The degassing module 101 shown in Fig. 13 was used as the simulation model for Comparative Example 1. The degassing module 101 shown in Fig. 13 is basically the same as the degassing module 1 shown in Fig. 1, and differs from the degassing module 1 shown in Fig. 1 only in that it does not have a baffle 6. The simulation model for Example 1 is a model equipped with one baffle, the simulation model for Example 2 is a model equipped with two baffles, and the simulation model for Comparative Example 1 is a model equipped with no baffle.

The flow rate of the liquid flowing through space S2 was calculated by simulation for the simulation models of Examples 1 and 2 and Comparative Example 1. ANSYS FLUENT analysis software was used. Simulation conditions included water at 25°C as the liquid model, and a constant resistance value was set as the resistance to liquid passage through the hollow fiber membrane bundle. Six points were used to calculate the liquid flow rate in space S2 on the opposite side of pipe 2 from the housing liquid inlet/drain port 43 and in space S2 on the housing liquid inlet/drain port 43 side of pipe 2. The calculation points for the liquid flow rate in space S2 on the opposite side of pipe 2 from the housing liquid inlet/drain port 43 were numbered 1 through 6 in order of proximity to the pipe liquid inlet/drain port 22. The calculation points for the liquid flow rate in space S2 on the housing liquid inlet/drain port 43 side of pipe 2 were numbered 7 through 12 in order of proximity to the pipe liquid inlet/drain port 22. The calculation results are shown in Figure 14.

As shown in Figure 14, in the space S2 on the opposite side of the housing supply/discharge port 43 of the pipe 2, there was almost no variation in flow rate throughout the entire extension direction D1 in both Examples 1 and 2 and Comparative Example 1.

In the space S2 on the housing liquid supply/drainage port 43 side of the pipe 2, in Comparative Example 1, the liquid flow rate was small at positions far from the housing liquid supply/drainage port 43 and large at positions close to the housing liquid supply/drainage port 43. In contrast, in both Examples 1 and 2, there was no significant variation in the flow rate across the entire extension direction D1, and the variation in the flow rate was significantly smaller than in Comparative Example 1. Furthermore, Example 2 had smaller variation in the flow rate than Example 1.

These results show that the installation of baffles can reduce the variation in the liquid flow rate within the housing. Furthermore, it was found that increasing the number of baffles can further reduce the variation in the liquid flow rate within the housing.

1...Degassing module, 1A...Degassing module, 1B...Degassing module, 1C...Degassing module, 1D...Degassing module, 1E...Degassing module, 2...Pipe, 2a...First end, 2b...Second end, 3...Hollow fiber membrane bundle, 3a...First end, 3b...Second end, 4...Housing, 4a...Cylindrical body, 4b...First lid portion, 4c...Second lid portion, 5...Partition portion, 6...Baffle, 6A...Baffle, 6B...Baffle, 6C...Baffle, 7...Second baffle, 8...Hollow fiber membrane fabric, 8a...Inner surface of fabric, 9...Warp yarn, 10...Molten resin 21...pipe internal flow path, 22...pipe liquid supply/discharge port, 23...pipe sealing portion, 24...hole, 25...hole-formed portion, 26...non-hole-formed portion, 31...hollow fiber membrane, 32...hollow portion, 41...first air intake port, 42...second air intake port, 43...housing liquid supply/discharge port, 51...first sealing portion, 52...second sealing portion, 101...degassing module, A...central axis, D1...extension direction, D2...circumferential direction, D3...radial direction, G...gas, L...liquid, R1...internal region, R2...external region, S1...intermembrane space, S2...space, S3...first internal region, S4...second internal region.

Claims (21)

a pipe having a plurality of holes formed therein;
a hollow fiber membrane bundle in which a plurality of hollow fiber membranes extending along the extension direction of the pipe are bundled together and arranged around the pipe so as to cover the plurality of holes;
a housing that accommodates the pipe and the hollow fiber membrane bundle so that a space is formed between the pipe and the hollow fiber membrane bundle;
a partition that divides the area within the housing into an internal area including hollow portions of the plurality of hollow fiber membranes and an external area including inter-membrane spaces between the plurality of hollow fiber membranes;
a baffle disposed in the inter-membrane space and extending in a direction intersecting the extension direction;
the pipe has a pipe supply/discharge port formed at one end thereof and open to the outside of the housing, and a pipe sealing portion that seals the pipe at the other end thereof;
The housing has an air intake port communicating with the internal region and a housing liquid supply/discharge port communicating with the external region.
Degassing module. The baffle extends in the circumferential direction of the pipe.
The degassing module of claim 1 . The baffle extends across the entire inter-membrane space in the circumferential direction.
The degassing module according to claim 2 . The baffle is provided in a part of the inter-membrane space in the circumferential direction.
The degassing module according to claim 2 . the baffle is provided on the housing liquid supply/discharge port side of the pipe as viewed from the extension direction, and is not provided on the opposite side of the pipe from the housing liquid supply/discharge port as viewed from the extension direction.
The degassing module of claim 1 . The baffle extends radially of the pipe.
The degassing module of claim 1 . The baffle extends across the entire inter-membrane space in the radial direction.
The degassing module according to claim 6. The baffle is provided in a part of the inter-membrane space in the radial direction.
The degassing module according to claim 6. the baffle extends from the pipe to an end of the inter-membrane space opposite the pipe in the radial direction of the pipe;
The degassing module of claim 1 . the baffle extends from a position spaced apart from the pipe to an end of the inter-membrane space opposite the pipe in the radial direction of the pipe;
The degassing module of claim 1 . The baffle extends in a direction inclined relative to the radial direction of the pipe.
The degassing module of claim 1 . The partition portion is
a first sealing portion that holds one end of the hollow fiber membrane bundle and seals spaces among the pipe, the housing, and the plurality of hollow fiber membranes;
a second sealing portion that is disposed on the opposite side of the pipe liquid supply/discharge port of the first sealing portion in the extending direction, and that holds the other end of the hollow fiber membrane bundle to seal spaces between the pipe, the housing, and the plurality of hollow fiber membranes,
The plurality of holes of the pipe are formed between the first sealing portion and the second sealing portion in the extension direction.
The degassing module of claim 1 . the housing liquid supply/discharge port is located near the second sealing portion,
The baffle is disposed on the pipe liquid supply/discharge port side of the housing liquid supply/discharge port in the extension direction.
The degassing module of claim 12. the baffle is disposed in a region on the housing liquid supply/discharge port side when a region between the first sealing portion and the housing liquid supply/discharge port in the extension direction is divided into two equal parts.
The degassing module of claim 13. The baffle is disposed near the housing inlet/outlet port.
The degassing module of claim 13. The baffle extends in the extension direction in a direction away from the housing liquid supply/discharge port as it moves away from the pipe.
The degassing module of claim 13. a second baffle disposed in the intermembrane space and extending in a direction intersecting the extension direction, the second baffle being disposed at a position different from the baffle in the extension direction;
The degassing module of claim 1 . The second baffle is disposed on the pipe supply/discharge port side of the baffle in the extension direction.
18. The degassing module of claim 17. the baffle is disposed on the pipe liquid supply/drain port side of the housing liquid supply/drain port in the extension direction,
The second baffle is disposed on the opposite side of the housing liquid supply/discharge port from the pipe liquid supply/discharge port in the extension direction.
18. The degassing module of claim 17. The pipe is not provided with any member for sealing the pipe other than the pipe sealing portion.
The degassing module of claim 1 . 21. The degassing module according to claim 1, wherein air is drawn into the internal region through the air inlet, and liquid is supplied to the external region through the pipe liquid supply/discharge port or the housing liquid supply/discharge port.
How to degas a liquid.