Degassing method and degassing module for liquid

Abstract

a first sealing portion sealing the end of the liquid distribution pipe in a first extension direction, the end of the hollow fiber membranes in the first extension direction, and spaces between the hollow fiber membranes; a second sealing portion sealing the end of the liquid distribution pipe in a second extension direction, the end of the hollow fiber membranes in the second extension direction, and spaces between the hollow fiber membranes; a liquid supply port; and a liquid discharge port. The method for degassing a liquid using a degassing module includes: a liquid distribution pipe; a plurality of hollow fiber membranes arranged around the liquid distribution pipe; a cylindrical portion accommodating the liquid distribution pipe and the plurality of hollow fiber membranes; a first sealing portion sealing the end of the liquid distribution pipe in a first extension direction, the end of the plurality of hollow fiber membranes in the first extension direction, and spaces between the cylindrical portion; a liquid supply port; and a liquid discharge port. The method comprises: aspirating the hollow portions of the plurality of hollow fiber membranes; 5 The liquid is supplied from the liquid supply port to the liquid distribution pipe so as to satisfy the relationship ≧0.2.

Description

[Technical Field]

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

[0002] Patent Document 1 describes a degassing module that uses multiple hollow fiber membranes for degassing. This degassing module is configured by housing a hollow fiber membrane bundle, in which multiple hollow fiber membranes are bundled into a cylindrical shape. This hollow fiber degassing module is also configured by providing a baffle plate between the hollow fiber membrane bundle and the flow path of the outlet port. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Chinese Patent Application Publication No. 110052060 Summary of the Invention [Problem to be solved by the invention]

[0004] When a liquid is passed through a degassing module at a high flow rate, if the baffle plate described in Patent Document 1 is installed, the flow path is narrowed, resulting in increased pressure loss of the liquid. Furthermore, uneven flow occurs in the liquid, shortening the contact time of the liquid with the hollow fiber membrane. As a result, the degassing efficiency decreases. Therefore, in an attempt to improve the degassing efficiency, a liquid was passed through a degassing module at a high flow rate without the baffle plate described in Patent Document 1, but a new problem arose: the hollow fiber membrane was drawn into the outlet port.

[0005] Therefore, an object of the present disclosure is to provide a liquid degassing method and degassing module that can improve degassing efficiency while suppressing breakage of hollow fiber membranes when a large flow rate is achieved. [Means for solving the problem]

[0006] The present inventors have conducted further research to solve the above problems and have discovered that rupture of the hollow fiber membranes can be suppressed even at high flow rates by ensuring a predetermined relationship between the clearance between the liquid discharge port and the plurality of hollow fiber membranes, the membrane area of ​​the hollow fiber membranes, and the liquid flow rate. The present disclosure is based on this discovery.

[0007] [1] A method for degassing a liquid according to the present disclosure includes a liquid circulation pipe having a plurality of openings formed therein to form a liquid flow passage; a plurality of hollow fiber membranes arranged around the liquid circulation pipe so as to cover the plurality of openings; a cylindrical portion accommodating the liquid circulation pipe and the plurality of hollow fiber membranes; a first sealing portion sealing between an end portion of the liquid circulation pipe on the first extension direction side, ends of the plurality of hollow fiber membranes on the first extension direction side, and the cylindrical portion, so that the hollow portions of the plurality of hollow fiber membranes open in a first extension direction which is one direction in the extension direction of the liquid circulation pipe; a liquid supply port for supplying liquid to the liquid circulation pipe; and a liquid discharge port provided on the cylindrical portion for discharging the liquid that has come out of the liquid circulation pipe, the hollow portions of the plurality of hollow fiber membranes being suctioned, and the flow rate of the liquid supplied from the liquid supply port to the liquid circulation pipe is expressed as C / (A×Q)×10, where C is the clearance between the liquid discharge port and the plurality of hollow fiber membranes, A is the membrane area of ​​the plurality of hollow fiber membranes, and Q is the flow rate of the liquid supplied from the liquid supply port to the liquid circulation pipe. 5 Liquid is supplied from the liquid supply port to the liquid distribution pipe so as to satisfy the relationship of ≧0.2.

[0008] In this liquid degassing method, C / (A×Q)×10 5 In order to supply liquid from the liquid supply port to the liquid distribution pipe so as to satisfy the relationship of ≧0.2, the baffle plate described in Patent Document 1 is not provided, and the liquid can be distributed over a 50 m 3 / h or 100m 3When a liquid is supplied at a high flow rate, such as 10 ...

[0009] [2] In the liquid degassing method described in [1], water may be supplied as the liquid from the liquid supply port to the liquid circulation pipe. In this liquid degassing method, water is supplied from the liquid supply port to the liquid circulation pipe, so that water can be degassed at a large flow rate while preventing breakage of the hollow fiber membrane.

[0010] [3] A degassing module according to the present disclosure includes a liquid circulation pipe having a plurality of openings formed therein to form a liquid circulation path; a plurality of hollow fiber membranes arranged around the liquid circulation pipe so as to cover the plurality of openings; a cylindrical portion accommodating the liquid circulation pipe and the plurality of hollow fiber membranes; a first sealing portion sealing between an end portion of the liquid circulation pipe on the first extension direction side, an end portion of the plurality of hollow fiber membranes on the first extension direction side, and the cylindrical portion so that the hollow portions of the plurality of hollow fiber membranes open in a first extension direction which is one direction in the extension direction of the liquid circulation pipe; the second sealing portion sealing the gap between the end of the liquid circulation pipe on the second extension direction side, the end of the plurality of hollow fiber membranes on the second extension direction side, and the tubular portion so as to open in a second extension direction which is the direction opposite to the first sealing portion; a liquid supply port for supplying liquid to the liquid circulation pipe; and a liquid discharge port provided on the tubular portion for discharging liquid that has exited from the liquid circulation pipe, wherein the clearance between the liquid discharge port and the plurality of hollow fiber membranes is C, the membrane area of ​​the plurality of hollow fiber membranes is A, and the flow rate of the liquid supplied from the liquid supply port to the liquid circulation pipe is C / (A×Q)×10 5 The clearance and membrane area are set so as to satisfy the relationship of ≧0.2.

[0011] In this degassing module, C / (A×Q)×10 5 Since the clearance C and the membrane area A are set so as to satisfy the relationship of ≥ 0.2, even without providing the baffle plate described in Patent Document 1, the 3 / h or 100m 3 When a liquid is supplied at a high flow rate, such as 10 ...

[0012] [4] a first sealing part that seals between the end of the liquid circulation pipe on the first extension direction side, the ends of the hollow fiber membranes on the first extension direction side, and the cylindrical part, so that the hollow portions of the hollow fiber membranes open in a first extension direction that is one direction in the extension direction of the liquid circulation pipe; a second sealing part that seals between the end of the liquid circulation pipe on the second extension direction side, the ends of the hollow fiber membranes on the second extension direction side, and the cylindrical part, so that the hollow portions of the hollow fiber membranes open in a second extension direction that is the opposite direction to the first extension direction in the extension direction; a liquid supply port that supplies liquid to the liquid circulation pipe; and a liquid discharge port that is provided in the cylindrical part and that discharges liquid that has flowed out of the liquid circulation pipe.

[0013] This degassing module is a degassing module used in the degassing method described in [1] or [2] above. Therefore, even without providing the baffle plate described in Patent Document 1, the degassing module can be used in a 50 m 3 / h or 100m 3 When a liquid is supplied at a high flow rate, such as 10 ...

[0014] [5] In the degassing module according to [3] or [4], the first and second sealing parts may divide the area inside the tubular part into an internal area including hollow portions of the hollow fiber membranes and an external area including the liquid flow path of the liquid distribution pipe, with the hollow fiber membranes as the boundary. In this degassing module, the first and second sealing parts divide the area inside the tubular part into an internal area including hollow portions of the hollow fiber membranes and an external area including the liquid flow path of the liquid distribution pipe, with the hollow fiber membranes as the boundary. This makes it easy to separate the internal area from the external area.

[0015] [6] In the degassing module according to any one of [3] to [5], the liquid supply port may be connected to an end of the liquid circulation pipe in the second extension direction, and the end of the liquid circulation pipe in the first extension direction may be blocked. In this degassing module, the end of the liquid circulation pipe in the first extension direction is blocked, and the liquid supply port is connected to the end of the liquid circulation pipe in the second extension direction. Therefore, when liquid is supplied to the liquid supply port, the liquid is supplied to the liquid circulation pipe, exits the liquid circulation pipe through the multiple openings, and comes into contact with the multiple hollow fiber membranes to be degassed. After that, the liquid that has come into contact with the multiple hollow fiber membranes and is degassed is discharged from the liquid discharge port without returning to the liquid circulation pipe. In other words, the liquid does not flow in a direction that presses the multiple hollow fiber membranes against the liquid circulation pipe, but rather in a direction that moves the multiple hollow fiber membranes away from the liquid circulation pipe. This makes it possible to suppress an increase in pressure loss when the liquid passes through the multiple hollow fiber membranes, thereby suppressing a decrease in the liquid flow rate. As a result, for example, a liquid supply device with a relatively low output can be used to supply liquid to the degassing module.

[0016] [7] The degassing module according to [6] may further comprise a first lid connected to an end of the tubular portion in the first extension direction, a second lid connected to an end of the tubular portion in the second extension direction, and a gas port for discharging gas that has permeated the plurality of hollow fiber membranes, wherein the gas port may be provided in 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 tubular portion, and the gas port is provided in at least one of the first lid and the second lid, making it easy to manufacture the degassing module.

[0017] [8] In the degassing module described in [7], the first cover may form a first end communication space that communicates with the hollow portions of the 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 cover forms a first end communication space that communicates with the hollow portions of the plurality of hollow fiber membranes, and the gas port has a first end gas port adjacent to the first end communication space and communicating with the first end communication space. This makes it possible to easily manufacture a degassing module that can suction the hollow portions of the plurality of hollow fiber membranes from the end on the first extension direction side.

[0018] [9] In the degassing module described in [7] or [8], the second cover may form a second end communication space that communicates with the hollow portions of the 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 cover forms a second end communication space that communicates with the hollow portions of the plurality of hollow fiber membranes, and the gas port has a second end gas port adjacent to the second end communication space and communicating with the second end communication space. This makes it possible to easily manufacture a degassing module that can suction the hollow portions of the plurality of hollow fiber membranes from the end on the second extension direction side. [Effects of the Invention]

[0019] According to the present disclosure, breakage of hollow fiber membranes can be suppressed even at high flow rates. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 2 is a schematic cross-sectional view of a degassing module according to an embodiment. [Figure 2] FIG. 2 is a schematic front view of the degassing element. [Figure 3] FIG. 3 is a schematic cross-sectional view taken along line III-III shown in FIG. [Figure 4] FIG. 3 is a schematic cross-sectional view showing a part of the degassing element shown in FIG. 2. [Figure 5] FIG. 3 is a schematic cross-sectional view showing a part of the degassing element shown in FIG. 2. [Figure 6] 2 is a schematic cross-sectional view showing a part of the degassing module shown in FIG. 1. [Figure 7] 2 is a schematic cross-sectional view showing a part of the degassing module shown in FIG. 1. [Figure 8] 2 is a schematic cross-sectional view showing a part of the degassing module shown in FIG. 1. [Figure 9] FIG. 10 is a schematic cross-sectional view of another example of a degassing module. DETAILED DESCRIPTION OF THE INVENTION

[0021] Hereinafter, a degassing module and a liquid degassing method according to an embodiment will be described with reference to the drawings. In all the drawings, the same or corresponding parts are designated by the same reference numerals, and redundant explanations will be omitted.

[0022] [Degassing module] FIG. 1 is a schematic cross-sectional view of a degassing module according to an embodiment. As shown in FIG. 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 may be, for example, tap water, drinking water, pure water, ultrapure water, seawater, industrial water, or other water; an aqueous solution in which ammonium sulfate, a surfactant, or the like is dissolved; an organic solvent such as alcohol or hydrocarbon; or an ionic liquid. The degassing module 1 includes a degassing element 2, a housing 3, a blocking section 5, and a partition section 7. Note that FIG. 1 shows only the housing 3 in cross section.

[0023] Fig. 2 is a schematic front view of a degassing element. Fig. 3 is a schematic cross-sectional view taken along line III-III in Fig. 2. Fig. 4 is a schematic cross-sectional view showing a portion of the degassing element shown in Fig. 2. Fig. 5 is a schematic cross-sectional view showing a portion of the degassing element shown in Fig. 2. As shown in Figs. 1 to 5, the degassing element 2 is for degassing a liquid L. The degassing element 2 includes a liquid distribution pipe 21, a plurality of hollow fiber membranes 22, a first fixing part 24, and a second fixing part 25.

[0024] The liquid circulation pipe 21 is a cylindrical member extending in the extension direction D2. One of the two directions of the extension direction D2 is referred to as a first extension direction D21, and the other direction is referred to as a second extension direction D22. In FIG. 2, the upper side is the first extension direction D21, and the lower side is the second extension direction D22. The end of the degassing element 2 on the first extension direction D21 side is referred to as a first element end 2a, and the end of the degassing element 2 on the second extension direction D22 side is referred to as a second element end 2b.

[0025] The liquid circulation pipe 21 forms a liquid circulation passage 21a. The liquid circulation passage 21a is a flow path (internal flow path) through which the liquid L can flow, and is formed by the inner circumferential surface of the liquid circulation pipe 21. The liquid circulation pipe 21 extends over the entire area in the extension direction D2 of the degassing element 2. That is, the liquid circulation pipe 21 extends from the end of the degassing element 2 in the first extension direction D21 to the end of the degassing element 2 in the second extension direction D22. The liquid circulation passage 21a of the liquid circulation pipe 21 is open in the first extension direction D21 and the second extension direction D22. The opening of the liquid circulation passage 21a of the liquid circulation pipe 21 on the first extension direction D21 side is referred to as a first-end liquid circulation pipe opening 21b, and the opening of the liquid circulation passage 21a of the liquid circulation pipe 21 on the second extension direction D22 side is referred to as a second-end liquid circulation pipe opening 21c. In the degassing element 2, the liquid flow passage 21a of the liquid flow pipe 21 is not provided with a member such as a baffle that prevents the liquid L from moving in the extending direction D2.

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

[0027] The plurality of hollow fiber membranes 22 extend along the liquid distribution pipe 21 and are arranged around the liquid distribution pipe 21 so as to cover the plurality of openings 21d. The plurality of hollow fiber membranes 22 extending along the liquid distribution pipe 21 means that the plurality of hollow fiber membranes 22 extend along the extension direction D2 in the initial state (unused state) of the degassing element 2. The plurality of hollow fiber membranes 22 form a membrane bundle having a substantially cylindrical shape as a whole.

[0028] The plurality of hollow fiber membranes 22 are formed, for example, by a hollow fiber membrane fabric (not shown) woven in the shape of a bamboo blind. The hollow fiber membrane fabric is a fabric in which a plurality of hollow fiber membranes 22 serving as weft yarns are woven with warp yarns (not shown). In the hollow fiber membrane fabric, the plurality of hollow fiber membranes 22 are arranged in the shape of a bamboo blind. The hollow fiber membrane fabric is wound around the liquid distribution pipe 21 so that the plurality of hollow fiber membranes 22 extend in the extension direction D2 and cover the plurality of openings 21d.

[0029] The hollow portions 22a of the hollow fiber membranes 22 are flow paths (intra-membrane flow paths) through which gas G can flow, and are formed by the inner circumferential surfaces of the hollow fiber membranes 22. The plurality of hollow fiber membranes 22 extend over the entire area in the extension direction D2 of the degassing element 2. That is, the plurality of hollow fiber membranes 22 extend from the end of the degassing element 2 in the first extension direction D21 to the end of the degassing element 2 in the second extension direction D22. The hollow portions 22a of the plurality of hollow fiber membranes 22 are open in the first extension direction D21 and the second extension direction D22. The hollow portions 22a of the plurality of hollow fiber membranes 22 refer to the hollow portions 22a of each of the plurality of hollow fiber membranes 22. The openings on the first extension direction D21 side of the hollow portions 22a of the multiple hollow fiber membranes 22 are referred to as first end hollow fiber membrane openings 22b, and the openings on the second extension direction D22 side of the hollow portions 22a of the multiple hollow fiber membranes 22 are referred to as second end hollow fiber membrane openings 22c.

[0030] The hollow fiber membrane 22 is a hollow fiber membrane that allows gas G to pass through but not liquid L. The material, shape, and 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; silicone resins such as polydimethylsiloxane and its copolymers; and fluorine-based resins such as PTFE and vinylidene fluoride. Examples of the shape (sidewall shape) of the hollow fiber membrane 22 include a porous membrane, a microporous membrane, and a homogeneous membrane (non-porous membrane) that does not have any pores. Examples of the form of the hollow fiber membrane 22 include a symmetric membrane (homogeneous membrane) in which the entire membrane has a homogeneous chemical or physical structure, and an asymmetric membrane (heterogeneous membrane) in which the chemical or physical structure of the 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. Non-porous means that it does not have pores through which a liquid can pass. Porous refers to the presence of pores through which a liquid can pass. In this case, the dense layer may be formed anywhere within 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] There are no particular limitations on the outer diameter of the hollow fiber membrane 22. From the viewpoint of increasing the membrane area, the outer diameter of the hollow fiber membrane 22 can be, for example, 1000 μm or less, preferably 700 μm or less, and more preferably 400 μm or less. On the other hand, from the viewpoint of suppressing breakage, the outer diameter of the hollow fiber membrane 22 can be, for example, 50 μm or more, preferably 100 μm or more, and more preferably 150 μm or more.

[0032] The first fixing portion 24 is located at the first element end portion 2a and fixes the plurality of hollow fiber membranes 22 to the liquid circulation pipe 21 so as to seal the gap between the liquid circulation pipe 21 and the plurality of hollow fiber membranes 22 and leave the hollow portions 22a of the plurality of hollow fiber membranes 22 open. That is, the first fixing portion 24 fixes the end of the plurality of hollow fiber membranes 22 on the first extending direction D21 side to the liquid circulation pipe 21. The first fixing portion 24 seals the gap between the liquid circulation pipe 21 and the plurality of hollow fiber membranes 22. Furthermore, the first fixing portion 24 is not provided in the liquid circulation passage 21a of the liquid circulation pipe 21 or the hollow portions 22a of the plurality of hollow fiber membranes 22, so that the liquid circulation passage 21a of the liquid circulation pipe 21 and the hollow portions 22a of the plurality of hollow fiber membranes 22 are open. The first fixing portion 24 is formed of, for example, resin.

[0033] The second fixing portion 25 is located at the second element end portion 2b and fixes the plurality of hollow fiber membranes 22 to the liquid circulation pipe 21 so as to seal the gap between the liquid circulation pipe 21 and the plurality of hollow fiber membranes 22 and leave the hollow portions 22a of the plurality of hollow fiber membranes 22 open. That is, the second fixing portion 25 fixes the end of the plurality of hollow fiber membranes 22 on the second extending direction D22 side to the liquid circulation pipe 21. The second fixing portion 25 seals the gap between the liquid circulation pipe 21 and the plurality of hollow fiber membranes 22. Furthermore, the second fixing portion 25 is not provided in the liquid circulation passage 21a of the liquid circulation pipe 21 or the hollow portions 22a of the plurality of hollow fiber membranes 22, so that the liquid circulation passage 21a of the liquid circulation pipe 21 and the hollow portions 22a of the plurality of hollow fiber membranes 22 are open. The second fixing portion 25 is formed of, for example, resin.

[0034] The plurality of hollow fiber membranes 22 are not covered by a member 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.

[0035] Fig. 6 is a schematic cross-sectional view showing a part of the degassing module shown in Fig. 1. Fig. 7 is a schematic cross-sectional view showing a part of the degassing module shown in Fig. 1. Fig. 8 is a schematic cross-sectional view showing a part of the degassing module shown in Fig. 1. As shown in Figs. 1, 2, and 6 to 8, the housing 3 accommodates the degassing element 2 so that a gap S1 is formed between the degassing element 2 and the housing 3. This gap S1 is a space between the degassing element 2 and the housing 3 through which the liquid L can flow.

[0036] The housing 3 comprises a cylindrical portion 31 that surrounds the degassing element 2, a first lid portion 32 that is connected to one end of the cylindrical portion 31, and a second lid portion 33 that is connected to the end of the cylindrical portion 31 opposite the first lid portion 32.

[0037] The tubular portion 31 is formed in a cylindrical shape extending in an extension direction D1. The extension direction D1 is also the opposing direction between the first cover portion 32 and the second cover portion 33. One of the extension directions D1 is referred to as a first extension direction D11, and the other is referred to as a second extension direction D12. In FIG. 1 , the upper side is the first extension direction D11, and the lower side is the second extension direction D12. The tubular portion 31 accommodates the degassing element 2 so as to surround the periphery of the degassing element 2. In this embodiment, the tubular portion 31 accommodates the degassing element 2 so that the extension direction D2 of the degassing element 2 coincides with the extension direction D1 of the tubular portion 31. Therefore, the extension direction D1 of the tubular portion 31 and the extension direction D2 of the degassing element 2 are the same direction.

[0038] The first lid portion 32 is connected to the end of the tubular portion 31 on the first extension direction D11 side so as to cover the opening of the tubular portion 31 on the first extension direction D11 side. The second lid portion 33 is connected to the end of the tubular portion 31 on the second extension direction D12 side so as to cover the opening of the tubular portion 31 on the second extension direction D12 side. The first lid portion 32 and the second lid portion 33 are detachably connected to the tubular portion 31. In the housing 3, the degassing element 2 can be detached from the tubular portion 31 and replaced by removing at least one of the first lid portion 32 and the second lid portion 33 from the tubular portion 31. The detachable connection of the first lid portion 32 and the second lid portion 33 to the tubular portion 31 can be achieved by, for example, screwing, fitting, or the like.

[0039] To enable degassing of a large volume of liquid L, the volume inside the housing 3 is, for example, 10 L or more and 80 L or less. From the same perspective, the inner diameter of the tubular portion 31 is, for example, 10 cm or more and 50 cm or less. From the same perspective, the length of the tubular portion 31 in the extension direction D2 is, for example, 30 cm or more and 70 cm or less.

[0040] The closure portion 5 closes the end 21f of the liquid flow passage 21a of the liquid circulation pipe 21 on the first extension direction D21 side. That is, the closure portion 5 closes the liquid flow passage 21a at the end 21f of the liquid circulation pipe 21 on the first extension direction D21 side. The closure portion 5 is fitted into the end of the liquid flow passage 21a of the liquid circulation pipe 21 on the first extension direction D21 side. The closure portion 5 is also called a plug, etc. The closure portion 5 may be formed integrally with the first lid portion 32. The closure portion 5 prevents the liquid L supplied to the liquid flow passage 21a of the liquid circulation pipe 21 from being discharged from the liquid circulation pipe 21 in the first extension direction D21. Therefore, the liquid L is not discharged from the liquid circulation pipe 21 in the first extension direction D21, but is discharged radially outward from the liquid circulation pipe 21 through the multiple openings 21d formed in the liquid circulation pipe 21.

[0041] In addition, in the liquid flow passage 21a of the liquid flow pipe 21, other than the blocking portion 5, no member for preventing the movement of the liquid L in the extending direction D2 is provided.

[0042] The partition 7 divides the area inside the housing 3 into an inner area R1 and an outer area R2, with the plurality of hollow fiber membranes 22 as the boundary. The inner area R1 is an area including the hollow portions 22a of the plurality of hollow fiber membranes 22. The outer area R2 is an area including the liquid flow passages 21a of the liquid flow pipe 21. Therefore, the hollow fiber membranes 22 form the boundary between the inner area R1 and the outer area R2. In other words, the inside (hollow portions 22a) of the hollow fiber membranes 22 forms the inner area R1, and the outside of the hollow fiber membranes 22 forms the outer area R2. The plurality of hollow fiber membranes 22 prevent the liquid L from passing from the outer area R2 to the inner area R1, but allow the gas G (such as dissolved gas in the liquid L or air bubbles contained in the liquid L) to pass from the outer area R2 to the inner area R1. In addition, since the liquid flow passage 21a of the liquid flow pipe 21 is connected to the outside of the liquid flow pipe 21 by multiple 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 connected to the liquid flow passage 21a of the liquid flow pipe 21.

[0043] The partition 7 has a first partition 71 and a second partition 72. The first partition 71 seals the gap between the first fixing portion 24 of the degassing element 2 and the cylindrical portion 31. The second partition 72 seals the gap between the second fixing portion 25 of the degassing element 2 and the cylindrical portion 31.

[0044] Therefore, the first fixing portion 24 and the first partition portion 71 function as a first sealing portion that seals between the end of the liquid circulation pipe 21 on the first extending direction D21 side, the end of the plurality of hollow fiber membranes 22 on the first extending direction D21 side, and the tubular portion 31, so that the hollow portions 22a of the plurality of hollow fiber membranes 22 open to the first extending direction D21 side. Furthermore, the second fixing portion 25 and the second partition portion 72 function as a second sealing portion that seals between the end of the liquid circulation pipe 21 on the second extending direction D22 side, the end of the plurality of hollow fiber membranes 22 on the second extending direction D22 side, and the tubular portion 31, so that the hollow portions 22a of the plurality of hollow fiber membranes 22 open to the second extending direction D22 side. The first fixing portion 24 and the first partition portion 71 that function as the first sealing portion and the second fixing portion 25 and the second partition portion 72 that function as the second sealing portion divide the region inside the tubular portion 31 into an inner region R1 and an outer region R2.

[0045] A first end communicating space S3 communicating with the hollow portions 22a of the plurality of hollow fiber membranes 22 is formed on the first extending direction D21 side of the degassing element 2. Furthermore, a second end communicating space S4 communicating with the hollow portions 22a of the plurality of hollow fiber membranes 22 is formed on the second extending direction D22 side of the degassing element 2. The first end communicating space S3 and the second end communicating space S4 communicate with the hollow portions 22a of the plurality of hollow fiber membranes 22, and therefore also form part of the internal region R1.

[0046] The first end communicating space S3 is a space surrounded by the first fixing part 24, the first partition part 71, and the first lid part 32 of the degassing element 2. The first end communicating space S3 is a space adjacent to the first element end part 2a of the degassing element 2 on the side in the first extending direction D21. The first end communicating space S3 is a space adjacent to the first end hollow fiber membrane opening 22b of the degassing element 2.

[0047] The second end communication space S4 is a space surrounded by the second fixing part 25, the second partition part 72, and the second lid part 33 of the degassing element 2. The second end communication space S4 is a space adjacent to the second element end part 2b of the degassing element 2 on the side in the second extending direction D22. The second end communication space S4 is a space adjacent to the second end hollow fiber membrane opening 22c of the degassing element 2.

[0048] The space S2 is a space surrounded by the liquid distribution pipe 21, the plurality of hollow fiber membranes 22, the first fixing portion 24, the second fixing portion 25 of the degassing element 2, the tubular portion 31, the first partition portion 71, and the second partition portion 72. The space S2 is adjacent to the first fixing portion 24 and the first partition portion 71 of the degassing element 2 on the side in the second extending direction D22, and adjacent to the second fixing portion 25 and the second partition portion 72 of the degassing element 2 on the side in the first extending direction D21.

[0049] Moreover, the first partition portion 71 seals the gap 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 gap 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, for example, from resin.

[0050] The housing 3 has a liquid supply port 35 for supplying the liquid L to the liquid flow passage 21a of the liquid distribution pipe 21, a liquid discharge port 36 for discharging the liquid L that has left the liquid distribution pipe 21, and a first-end gas port 38 and a second-end gas port 39 that are gas ports for discharging gas that has permeated the plurality of hollow fiber membranes 22. When the liquid L is degassed in vacuum mode, the first-end gas port 38 and the second-end gas port 39 are also referred to as 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 configured integrally with the housing 3 or may be separate members from the housing 3.

[0051] The liquid supply port 35 is provided in the second lid portion 33 and is a port that communicates between the inside and outside of the housing 3. The liquid supply port 35 extends in a pipe shape from the second lid portion 33 to the inside of the housing 3, and is connected to the end 21e of the liquid circulation pipe 21 on the second extension direction D22 side. The liquid supply port 35 is communicated with the liquid circulation passage 21a of the liquid circulation pipe 21.

[0052] The liquid discharge port 36 is a port that is provided in the tubular portion 31 and that communicates between the inside and the outside of the housing 3. The liquid discharge port 36 is provided, for example, near the end of the tubular portion 31 on the side of the first extending direction D11. The liquid discharge port 36 is adjacent to the space S2 and communicates with the space S2.

[0053] The first end gas port 38 is provided in the first cover portion 32 and is a port that communicates between the inside and outside of the housing 3. The first end gas port 38 is adjacent to the first end communicating space S3 and is communicated with the first end communicating space S3.

[0054] The second end gas port 39 is provided in the second cover portion 33 and is a port that communicates between the inside and outside of the housing 3. The second end gas port 39 is adjacent to the second end communicating space S4 and is communicated with the second end communicating space S4.

[0055] [Method for degassing liquids] Next, a description will be given of a method for degassing the liquid L using the degassing module 1. Here, as an example of a method for degassing the liquid L, a method for degassing the liquid L in a vacuum mode will be described.

[0056] 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 the liquid L is supplied to the liquid supply port 35 of the degassing module 1. The suction of the first end gas port 38 and the second end gas port 39 can be performed, for example, by connecting a suction device (not shown) such as a vacuum pump to the first end gas port 38 and the second end gas port 39 via piping or the like and activating this suction device. The supply of the liquid L to the liquid supply port 35 can be performed, for example, by connecting a liquid supply device (not shown) such as a liquid feed pump that sends out the liquid L via piping or the like to the liquid supply port 35 and activating this liquid supply device.

[0057] 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 is depressurized. Furthermore, when the 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 distribution pipe 21. The liquid L is then discharged from the multiple openings 21d of the liquid distribution pipe 21 into the space S2 and comes into contact with the multiple hollow fiber membranes 22. At this time, because the hollow portions 22a of the multiple hollow fiber membranes 22 are depressurized, gas G, such as dissolved gas in the liquid L and bubbles contained in the liquid L, permeates the multiple hollow fiber membranes 22. This degasses the liquid L. The degassed liquid L discharged into the space S2 is then discharged from the liquid discharge port 36. The gas G that has permeated the multiple hollow fiber membranes 22 passes through the hollow portions 22a of the multiple hollow fiber membranes 22, the first end communicating space S3, and the second end communicating space S4, and is discharged from the first end gas port 38 and the second end gas port 39.

[0058] [Clearance between the liquid outlet port and multiple hollow fiber membranes] Here, the liquid L flowing from the space S2 into the liquid discharge port 36 attempts to draw the plurality of hollow fiber membranes 22 into the liquid discharge port 36 due to its hydraulic force. As the flow rate of the liquid L increases, this hydraulic force becomes stronger, and attempts to draw the plurality of hollow fiber membranes 22 even more strongly into the liquid discharge port 36. If some of the plurality of hollow fiber membranes 22 are drawn into the liquid discharge port 36, there is a risk that some of the plurality of hollow fiber membranes 22 will be pressed against the edge of the liquid discharge port 36 and break. Therefore, this embodiment is configured to prevent some of the plurality of hollow fiber membranes 22 from being drawn into the liquid discharge port 36 and breaking, even when the flow rate of the liquid L becomes high.

[0059] More specifically, the clearance [m] between the liquid discharge port 36 and the plurality of hollow fiber membranes 22 is defined as C (hereinafter also referred to as "clearance C"), and the membrane area [m 2] is A (hereinafter also referred to as "membrane area A"), and the flow rate [m 3 / h] is defined as Q (hereinafter also referred to as "flow rate Q"). The liquid L supplied to the liquid circulation pipe 21 is, for example, water. The clearance C is the distance between the liquid discharge port 36 and the plurality of hollow fiber membranes 22 at the position where the liquid discharge port 36 and the plurality of hollow fiber membranes 22 are closest to each other.

[0060] The membrane area A refers to the membrane area of ​​the portion of the plurality of hollow fiber membranes 22 that functions as a degassing membrane. The portions of the plurality of hollow fiber membranes 22 that are fixed to the first fixing portion 24 and the second fixing portion 25 do not function as degassing membranes. Therefore, the membrane area A is the membrane area of ​​the plurality of hollow fiber membranes 22 between the first sealing portion (first fixing portion 24 and first partition portion 71) and the second sealing portion (second fixing portion 25 and second partition portion 72), and does not include the portions of the plurality of hollow fiber membranes 22 that are fixed to the first fixing portion 24 and the second fixing portion 25. The flow rate Q can be determined, for example, by measuring the flow rate of the liquid L supplied to the liquid supply port 35 or by measuring the flow rate of the liquid L discharged from the liquid discharge port 36.

[0061] In the liquid degassing method according to this embodiment, C / (A×Q)×10 5 The liquid L is supplied from the liquid supply port 35 to the liquid circulation pipe 21 so as to satisfy the relationship of ≧0.2.

[0062] Moreover, the degassing module 1 according to this embodiment is set to satisfy at least one of the following conditions (1) to (4). (1) C / (A×Q)×10 5 The clearance C, membrane area A, and flow rate Q are set so as to satisfy the relationship C / (A×Q)×10. Note that setting the flow rate Q in this manner means, for example, that a liquid supply device (not shown) that supplies liquid L to the liquid supply port 35 is set to supply liquid L at a flow rate Q that satisfies this relationship. Therefore, if the flow rate Q is fixed, C / (A×Q)×10 5The clearance C and the membrane area A may be set so as to satisfy the relationship of ≧0.2. (2) C / (A×Q)×10 5 The clearance C and the membrane area A are set so as to satisfy the relationship of ≧0.2. (3) 50 m from the liquid supply port 35 to the liquid distribution pipe 21 3 When a liquid L is supplied at a flow rate of / h, C / (A×50)×10 5 The clearance C and the membrane area A are set so as to satisfy the relationship of ≧0.2. (4) 100 m from the liquid supply port 35 to the liquid distribution pipe 21 3 When a liquid L is supplied at a flow rate of / h, C / (A×100)×10 5 The clearance C and the membrane area A are set so as to satisfy the relationship of ≧0.2.

[0063] The clearance C can be adjusted by, for example, adjusting the inner diameter of the tubular portion 31, the outer diameter of the hollow fiber membranes 22, the position of the degassing element 2 in the radial direction of the tubular portion 31, the inclination of the degassing element 2 with respect to the tubular portion 31, etc. In other words, the clearance C can be set to a predetermined value by setting the inner diameter of the tubular portion 31, the outer diameter of the hollow fiber membranes 22, the position of the degassing element 2 in the radial direction of the tubular portion 31, the inclination of the degassing element 2 with respect to the tubular portion 31, etc. For example, the clearance C can be increased by increasing the inner diameter of the tubular portion 31. Alternatively, the clearance C can be increased by decreasing the outer diameter of the hollow fiber membranes 22. Alternatively, the clearance C can be increased by shifting the degassing element 2 (liquid distribution pipe 21) from the radial center of the tubular portion 31 to the side opposite the liquid discharge port 6, for example, by changing the circumferential thickness of the first partition portion 71 and the second partition portion 72. In addition, the clearance C can be increased by changing the circumferential thickness of at least one of the first partition portion 71 and the second partition portion 72, and by tilting the extension direction D2 of the degassing element 2 relative to the extension direction D1 of the tubular portion 31 so that the degassing element 2 (liquid flow pipe 21) is inclined on the opposite side to the liquid discharge port 6.

[0064] The membrane area A can be adjusted, for example, by changing the number of the plurality of hollow fiber membranes 22, the outer diameter of each of the plurality of hollow fiber membranes 22, the length of the plurality of hollow fiber membranes 22, etc. In other words, by setting the number of the plurality of hollow fiber membranes 22, the outer diameter of each of the plurality of hollow fiber membranes 22, the length of the plurality of hollow fiber membranes 22, etc., the membrane area A can be set to a predetermined value.

[0065] As described above, in the liquid degassing method according to this embodiment, C / (A×Q)×10 5 ≧0.2. Therefore, even if the baffle plate described in Patent Document 1 is not provided, the liquid L is supplied from the liquid supply port 35 to the liquid distribution pipe 21. 3 / h or 100m 3 When the liquid L is supplied at a large flow rate, such as 1000 sq. ft. / h, the hollow fiber membranes 22 can be prevented from being drawn into the liquid discharge port 36 and breaking. This makes it possible to improve the degassing efficiency while preventing the hollow fiber membranes 22 from breaking when the flow rate is increased.

[0066] Furthermore, in this liquid degassing method, water is supplied as the liquid L from the liquid supply port 35 to the liquid circulation pipe 21, so that water can be degassed at a large flow rate while preventing the hollow fiber membranes 22 from breaking.

[0067] In the degassing module 1 according to this embodiment, C / (A×Q)×10 5 The clearance C and the membrane area A are set so as to satisfy the relationship of ≥ 0.2. Therefore, even without providing the baffle plate described in Patent Document 1, 3 / h or 100m 3 When a liquid is supplied at a large flow rate, such as 1000 sq. ft. / h, the hollow fiber membranes 22 can be prevented from being drawn into the liquid discharge port 36 and breaking. This makes it possible to improve the degassing efficiency while preventing breakage of the hollow fiber membranes 22 when the flow rate is increased.

[0068] In the degassing module 1 according to this embodiment, the liquid supply port 35 is connected to the liquid circulation pipe 21 by 50 m. 3When a liquid L is supplied at a flow rate of / h, C / (A×50)×10 5 The clearance C and the membrane area A are set so as to satisfy the relationship of ≥ 0.2. Therefore, even without providing the baffle plate described in Patent Document 1, 3 When the liquid L is supplied at a large flow rate of 1 / h, the hollow fiber membranes 22 can be prevented from being drawn into the liquid discharge port 36 and breaking. This makes it possible to improve the degassing efficiency while preventing the hollow fiber membranes 22 from breaking when the flow rate is increased.

[0069] In the degassing module 1 according to this embodiment, the liquid supply port 35 is connected to the liquid circulation pipe 21 by 100 m. 3 When a liquid L is supplied at a flow rate of / h, C / (A×100)×10 5 The clearance C and the membrane area A are set so as to satisfy the relationship of ≥ 0.2. Therefore, even without providing the baffle plate described in Patent Document 1, 3 When the liquid L is supplied at a large flow rate of 1 / h, the hollow fiber membranes 22 can be prevented from being drawn into the liquid discharge port 36 and breaking. This makes it possible to improve the degassing efficiency while preventing the hollow fiber membranes 22 from breaking when the flow rate is increased.

[0070] Furthermore, in the degassing module 1 according to this embodiment, the first sealing portion and the second sealing portion divide the area inside the tubular portion 31, with the hollow fiber membranes 22 as the boundary, into an inner area R1 including the hollow portions 22a of the plurality of hollow fiber membranes 22 and an outer area R2 including the liquid flow passages 21a of the liquid flow pipe 21. This makes it easy to divide the inner area R1 and the outer area R2.

[0071] Furthermore, in the degassing module 1 according to this embodiment, the end 21f of the liquid circulation pipe 21 on the first extension direction D21 side is closed, and the liquid supply port 35 is connected to the end 21e of the liquid circulation pipe 21 on the second extension direction D22 side. Therefore, when the liquid L is supplied to the liquid supply port 35, the liquid L is supplied to the liquid circulation pipe 21, exits the liquid circulation pipe 21 through the multiple openings 21d, and comes into contact with the multiple hollow fiber membranes 22 to be degassed. Thereafter, the liquid L that has come into contact with the multiple hollow fiber membranes 22 and is discharged from the liquid discharge port 36 without returning to the liquid circulation 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 circulation pipe 21, but rather flows in a direction that moves the multiple hollow fiber membranes 22 away from the liquid circulation pipe 21. This makes it possible to suppress an increase in pressure loss when the liquid L passes through the multiple hollow fiber membranes 22, and therefore to suppress a decrease in the flow rate of the liquid L. As a result, for example, a liquid supply device with a relatively low output can be used to supply the liquid L to the degassing module 1.

[0072] Furthermore, in the degassing module 1 according to this embodiment, the first cover portion 32 connected to the end of the tubular portion 31 on the first extending direction D11 side forms a first end communication space S3 that communicates with the hollow portions 22a of the plurality of 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, it is possible to easily manufacture a degassing module 1 that can suction the hollow portions 22a of the plurality of hollow fiber membranes 22 from the end on the first extending direction D21 side.

[0073] Furthermore, in the degassing module 1 according to this embodiment, the second cover portion 33 connected to the end of the tubular portion 31 on the second extending direction D12 side forms a second end communication space S4 that communicates with the hollow portions 22a of the plurality of 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, it is possible to easily manufacture a degassing module 1 that can suction the hollow portions 22a of the plurality of hollow fiber membranes 22 from the end on the second extending direction D22 side.

[0074] Although the preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to the above embodiments.

[0075] For example, in the above embodiment, the liquid discharge port is described as being provided near the end of the cylindrical portion in the first extension direction, but it may be provided at any position on the cylindrical portion. Fig. 9 is a schematic cross-sectional view of another example of a degassing module. In the degassing module 1A shown in Fig. 9, the liquid discharge port 36 is provided in the center of the cylindrical portion 31 in the extension direction D1.

[0076] In addition, in the above embodiment, the gas port is described as being provided in both the first lid portion and the second lid portion, but it may be provided in only one of the first lid portion and the second lid portion. [Example]

[0077] Next, examples of the present disclosure will be described, but the present disclosure is not limited to the following examples.

[0078] Example 1 A degassing module having the same configuration as the above embodiment was produced as Example 1. In the degassing module of Example 1, the membrane area A of the multiple hollow fiber membranes was 140 m 2 The clearance C between the liquid outlet port and the hollow fiber membranes is 17.9 × 10 -3 m (0.0179 m). Using the degassing module of Example 1, the maximum flow rate Q was 50 m 3 / h of water was supplied to the liquid supply port for 48 hours to perform degassing. After that, the degassing element was removed from the housing, and the breakage evaluation of multiple hollow fiber membranes was checked. In the breakage evaluation, if no broken hollow fiber membranes were found, it was rated A, and if broken hollow fiber membranes were found, it was rated B. The evaluation results are shown in Table 1.

[0079] (Comparative Example 1) A degassing module having the same configuration as the above embodiment was produced as Comparative Example 1. In the degassing module of Comparative Example 1, the clearance C between the liquid discharge port and the plurality of hollow fiber membranes was 13.9 × 10 -3 m (0.0139 m). Using the degassing module of Comparative Example 1, the maximum flow rate Q was 50 m 3 / h of water was supplied to the liquid supply port for 2 hours to perform degassing. After that, the degassing element was removed from the housing, and multiple hollow fiber membranes were evaluated for breakage. In the breakage evaluation, a case where no broken hollow fiber membranes were found was rated A, and a case where broken hollow fiber membranes were found was rated B. The evaluation results are shown in Table 1.

[0080] [Table 1]

[0081] As shown in Table 1, Example 1 has a C / (A×Q)×10 5 was 0.256, which is 0.2 or more, and the rupture evaluation of multiple hollow fiber membranes was A. In contrast, in Comparative Example 1, 5 The value was 0.185, which is less than 0.2, and the rupture evaluation of several hollow fiber membranes was B. From this result, C / (A×Q)×10 5 ≧0.2, the liquid can be 3 It is estimated that even if liquid is supplied at a large flow rate of 10 ... [Explanation of symbols]

[0082] 1... degassing module, 1A... degassing module, 2... degassing element, 2a... first element end, 2b... second element end, 3... housing, 5... blocking portion, 6... liquid discharge port, 7... partition portion, 21... liquid circulation pipe, 21a... liquid circulation path, 21b... first end liquid circulation pipe opening, 21c... second end liquid circulation pipe opening, 21d... opening, 21e... end, 21f... end, 22... hollow fiber membrane, 22a... hollow portion, 22b... first end hollow fiber membrane opening, 22c... second end hollow fiber membrane opening, 24... first fixing portion, 25... 2 fixed 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, 72...second partition part, C...clearance, D1...extension direction, D1 1...first extension direction, D12...second extension direction, D2...extension direction, D21...first extension direction, D22...second extension direction, G...gas, L...liquid, 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 a plurality of openings formed therein to form a liquid flow passage; a plurality of hollow fiber membranes arranged around the liquid distribution pipe so as to cover the plurality of openings; a cylindrical portion that accommodates the liquid distribution pipe and the plurality of hollow fiber membranes; a first sealing portion that seals between an end portion of the liquid circulation pipe on the first extension direction side, ends of the plurality of hollow fiber membranes on the first extension direction side, and the tubular portion, so that hollow portions of the plurality of hollow fiber membranes open in a first extension direction that is one direction in the extension direction of the liquid circulation pipe; a second sealing portion that seals between an end portion of the liquid distribution pipe on the second extension direction side, an end portion of the plurality of hollow fiber membranes on the second extension direction side, and the tubular portion, so that the hollow portions of the plurality of hollow fiber membranes open in a second extension direction that is the opposite direction to the first extension direction in the extension direction; a liquid supply port for supplying liquid to the liquid distribution pipe; a liquid discharge port provided in the cylindrical portion for discharging the liquid discharged from the liquid circulation pipe; A degassing method for degassing a liquid using a degassing module comprising: Suction is applied to the hollow portions of the plurality of hollow fiber membranes, When the clearance between the liquid discharge port and the plurality of hollow fiber membranes is C, the membrane area of ​​the plurality of hollow fiber membranes is A, and the flow rate of the liquid supplied from the liquid supply port to the liquid circulation pipe is Q, C / (A×Q)×10 ５ the liquid is supplied from the liquid supply port to the liquid circulation pipe so as to satisfy the relationship of ≧0.

2. How to degas a liquid.

2. Water is supplied as the liquid from the liquid supply port to the liquid circulation pipe. The method for degassing a liquid according to claim 1.

3. a liquid flow pipe having a plurality of openings formed therein to form a liquid flow passage; a plurality of hollow fiber membranes arranged around the liquid distribution pipe so as to cover the plurality of openings; a cylindrical portion that accommodates the liquid distribution pipe and the plurality of hollow fiber membranes; a first sealing portion that seals between an end portion of the liquid circulation pipe on the first extension direction side, ends of the plurality of hollow fiber membranes on the first extension direction side, and the tubular portion, so that hollow portions of the plurality of hollow fiber membranes open in a first extension direction that is one direction in the extension direction of the liquid circulation pipe; a second sealing portion that seals between an end portion of the liquid distribution pipe on the second extension direction side, an end portion of the plurality of hollow fiber membranes on the second extension direction side, and the tubular portion, so that the hollow portions of the plurality of hollow fiber membranes open in a second extension direction that is the opposite direction to the first extension direction in the extension direction; a liquid supply port for supplying liquid to the liquid distribution pipe; a liquid discharge port provided in the cylindrical portion for discharging the liquid discharged from the liquid circulation pipe, When the clearance between the liquid discharge port and the plurality of hollow fiber membranes is C, the membrane area of ​​the plurality of hollow fiber membranes is A, and the flow rate of the liquid supplied from the liquid supply port to the liquid circulation pipe is Q, C / (A×Q)×10 ５ The clearance and the membrane area are set so as to satisfy the relationship of ≧0.

2. Degassing module.

4. A degassing module used in the liquid degassing method according to claim 1 or 2, a liquid flow pipe having a plurality of openings formed therein to form a liquid flow passage; a plurality of hollow fiber membranes arranged around the liquid distribution pipe so as to cover the plurality of openings; a cylindrical portion that accommodates the liquid distribution pipe and the plurality of hollow fiber membranes; a first sealing portion that seals between an end portion of the liquid circulation pipe on the first extension direction side, ends of the plurality of hollow fiber membranes on the first extension direction side, and the tubular portion, so that hollow portions of the plurality of hollow fiber membranes open in a first extension direction that is one direction in the extension direction of the liquid circulation pipe; a second sealing portion that seals between an end portion of the liquid distribution pipe on the second extension direction side, an end portion of the plurality of hollow fiber membranes on the second extension direction side, and the tubular portion, so that the hollow portions of the plurality of hollow fiber membranes open in a second extension direction that is the opposite direction to the first extension direction in the extension direction; a liquid supply port for supplying liquid to the liquid distribution pipe; a liquid discharge port provided in the cylindrical portion for discharging the liquid discharged from the liquid circulation pipe, Degassing module.

5. the first sealing portion and the second sealing portion divide the region inside the tubular portion into an internal region including the hollow portions of the plurality of hollow fiber membranes and an external region including the liquid flow passage of the liquid flow pipe, with the plurality of hollow fiber membranes as a boundary. The degassing module according to claim 3 .

6. the liquid supply port is connected to an end of the liquid circulation pipe on the second extension direction side, an end portion of the liquid flow pipe on the first extension direction side is closed; The degassing module according to claim 3 .

7. a first lid portion connected to an end portion of the cylindrical portion in the first extension direction; a second cover portion connected to an end portion of the cylindrical portion in the second extending direction; a gas port for discharging gas that has permeated the plurality of hollow fiber membranes; The gas port is provided in at least one of the first lid portion and the second lid portion. The degassing module according to claim 6.

8. the first lid portion forms a first end communication space that is in communication with the hollow portions of the plurality of hollow fiber membranes, the gas port includes a first end gas port adjacent to the first end communication space and communicating with the first end communication space; The degassing module of claim 7.

9. the second lid portion forms a second end communication space that communicates with the hollow portions of the plurality of hollow fiber membranes, the gas port includes a second end gas port adjacent to the second end communication space and communicating with the second end communication space; The degassing module of claim 7.

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