Degassing element, degassing module, and liquid degassing method

Abstract

This deaeration element comprises: a liquid circulation pipe; a plurality of hollow fiber membranes disposed around the liquid circulation pipe; a suction pipe extending along the liquid circulation pipe; a first fixing part positioned at a first element end part and fixing the plurality of hollow fiber membranes and the suction pipe to the liquid circulation pipe; and a second fixing part positioned at a second element end part and fixing the plurality of hollow fiber membranes and the suction pipe to the liquid circulation pipe. The deaeration module comprises the deaeration element, a housing for storing the deaeration element, a first end communication space formation part, and a partition part for partitioning a region in the housing into an internal region and an external region with the plurality of hollow fiber membranes as a boundary. The first end communication space formation part forms a first end communication space for communicating a hollow part of the plurality of hollow fiber membranes with a hollow part of the suction pipe.

Description

[Technical Field]

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

[0002] Conventionally, degassing modules that degas a liquid using degassing elements having multiple hollow fiber membranes have been known. Also known are degassing modules in which multiple degassing elements are connected together to accommodate larger sizes or larger flow rates (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2020 / 067512 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, there has been a demand to reduce the concentration of carbon dioxide, a greenhouse gas, in the atmosphere in order to curb climate change. As one of the means to achieve this, methods of removing or capturing carbon dioxide from seawater are being considered. Because seawater contains a large amount of carbon dioxide, it is thought that reducing the carbon dioxide concentration in seawater can reduce the carbon dioxide concentration in the atmosphere.

[0005] Incidentally, degassing of liquids is often performed in sweep mode. Sweep mode is a method of degassing a liquid by supplying the liquid to the outside of a hollow fiber membrane and circulating a sweep gas inside the hollow fiber membrane. However, in order to degas a gas from a liquid to a high concentration, it is effective to perform the degassing in vacuum mode. Vacuum mode is a method of degassing a liquid by supplying the liquid to the outside of a hollow fiber membrane and suctioning (vacuuming) the inside of the hollow fiber membrane. In vacuum mode, the pressure difference between the inside and outside of the hollow fiber membrane is larger than in sweep mode, so more gas permeates the hollow fiber membrane than in sweep mode.

[0006] Here, hollow fiber membranes are formed to be elongated (thin and long) to increase the membrane area (contact area with the liquid), resulting in a high pressure loss of the fluid flowing through the hollow fiber membrane. Therefore, when conventional degassing modules are used to degas a liquid in vacuum mode, it is necessary to suction the inside of the hollow fiber membrane from both ends of the degassing element in order to efficiently suction the inside of the hollow fiber membrane. However, suctioning the inside of the hollow fiber membrane from both sides of the degassing element complicates the structure around the degassing element in the degassing module. This makes assembly and disassembly of the degassing module difficult, resulting in poor maintainability of the degassing module. Furthermore, when multiple degassing elements are connected in series to degas seawater at a high flow rate, the structure around the degassing element in the degassing module becomes even more complex.

[0007] Therefore, an object of the present disclosure is to provide a degassing element, a degassing module, and a method for degassing a liquid that have high degassing efficiency and can improve maintainability. [Means for solving the problem]

[0008] [1] A degassing element according to the present disclosure comprises: a liquid distribution pipe having a plurality of openings formed therein and extending in an extension direction; a plurality of hollow fiber membranes arranged around the liquid distribution pipe so as to extend along the liquid distribution pipe and cover the plurality of openings; a suction pipe extending along the liquid distribution pipe; a first fixing part located at a first element end which is an end in a first extension direction which is one direction in the extension direction, and fixing the plurality of hollow fiber membranes and the suction pipe to the liquid distribution pipe so as to seal between the liquid distribution pipe, the plurality of hollow fiber membranes, and the suction pipe and open the hollow portion of the liquid distribution pipe, the hollow portions of the plurality of hollow fiber membranes, and the hollow portion of the suction pipe; and a second fixing part located at a second element end which is an end in a second extension direction which is the opposite direction to the first extension direction, and fixing the plurality of hollow fiber membranes and the suction pipe to the liquid distribution pipe so as to seal between the liquid distribution pipe, the plurality of hollow fiber membranes, and the suction pipe and open the hollow portion of the liquid distribution pipe, the hollow portions of the plurality of hollow fiber membranes, and the hollow portion of the suction pipe.

[0009] In this degassing element, multiple hollow fiber membranes extending along the liquid distribution pipe are arranged around the liquid distribution pipe to cover the multiple openings. Therefore, when suction is applied to the hollow portions of the multiple hollow fiber membranes and liquid is supplied to the liquid distribution pipe, the liquid exits the liquid distribution pipe through the multiple openings and comes into contact with the multiple hollow fiber membranes, thereby being degassed. The degassing element also includes a suction pipe extending along the liquid distribution pipe. A first fixing part located at the end of the first element secures the multiple hollow fiber membranes and suction pipe to the liquid distribution pipe, sealing the gaps between the liquid distribution pipe, the multiple hollow fiber membranes, and the suction pipe, leaving the hollow portions of the liquid distribution pipe, the multiple hollow fiber membranes, and the suction pipe open. A second fixing part located at the end of the second element secures the multiple hollow fiber membranes and suction pipe to the liquid distribution pipe, sealing the gaps between the liquid distribution pipe, the multiple hollow fiber membranes, and the suction pipe, leaving the hollow portions of the liquid distribution pipe, the multiple hollow fiber membranes, and the suction pipe open. Therefore, the openings of the hollow portions of the hollow fiber membranes are connected to the openings of the hollow portion of the suction pipe at either the first element end or the second element end, and the hollow portions of the hollow fiber membranes and the hollow portion of the suction pipe are sucked from the other of the first element end or the second element end. This suction force is then transmitted through the hollow portion of the suction pipe, so that the hollow portions of the hollow fiber membranes are sucked from both the second element end side and the first element end side. In other words, the hollow portions of the hollow fiber membranes can be sucked from both ends in the extension direction without providing suction ports for sucking the hollow portions of the hollow fiber membranes at both the first element end and the second element end. This simplifies the structure of a degassing module using a degassing element, thereby achieving high degassing efficiency and improved maintainability.

[0010] [2] In the degassing element described in [1] above, the cross-sectional area of ​​the hollow portion of the suction pipe may be larger than the total cross-sectional area of ​​the hollow portions of the hollow fiber membranes. In this degassing element, the cross-sectional area of ​​the hollow portion of the suction pipe is larger than the total cross-sectional area of ​​the hollow portions of the hollow fiber membranes, so that the pressure loss (suction loss) caused by suction in the hollow portion of the suction pipe can be smaller than the pressure loss (suction loss) caused by suction in the hollow portions of the hollow fiber membranes. This allows the hollow portions of the hollow fiber membranes to be connected to the hollow portion of the suction pipe at either the first element end or the second element end, making it easier to suction the hollow portions of the hollow fiber membranes from either the first element end or the second element end when suction is applied to the hollow portions of the hollow fiber membranes and the hollow portion of the suction pipe at the other of the first element end or the second element end. Since the shape of the suction pipe is not as restricted as that of the hollow fiber membranes, the cross-sectional area of ​​the hollow portion of the suction pipe can be easily made larger than the total cross-sectional area of ​​the hollow portions of the hollow fiber membranes.

[0011] [3] In the degassing element according to [1] or [2] above, the suction pipe may be arranged outside the hollow fiber membranes. In this degassing element, the suction pipe is arranged outside the hollow fiber membranes, which makes it easier to arrange the hollow fiber membranes around the liquid distribution pipe and prevents the suction pipe from interfering with degassing of the liquid.

[0012] [4] The degassing element according to the above item [1] may be provided with a plurality of suction pipes. This degassing element has a plurality of suction pipes, which makes it easier to transmit the suction force.

[0013] [5] In the degassing element described in [4] above, the total cross-sectional area of ​​the hollow portions of the plurality of suction pipes may be larger than the total cross-sectional area of ​​the hollow portions of the plurality of hollow fiber membranes. In this degassing element, the total cross-sectional area of ​​the hollow portions of the plurality of suction pipes is larger than the total cross-sectional area of ​​the hollow portions of the plurality of hollow fiber membranes, so that the pressure loss caused by suction in the hollow portions of the plurality of suction pipes can be smaller than the pressure loss caused by suction in the hollow portions of the plurality of hollow fiber membranes. This makes it easier to suction the hollow portions of the plurality of hollow fiber membranes from either the first element end or the second element end when the hollow portions of the plurality of hollow fiber membranes and the hollow portions of the plurality of suction pipes are connected at either the first element end or the second element end, and suction is applied to the hollow portions of the plurality of hollow fiber membranes and the hollow portions of the plurality of suction pipes at the other of the first element end or the second element end.

[0014] [6] In the degassing element described in [4] or [5] above, the plurality of suction pipes may be arranged around the plurality of hollow fiber membranes. In this degassing element, the plurality of suction pipes are arranged around the plurality of hollow fiber membranes, which makes it easier to arrange the plurality of hollow fiber membranes around the liquid distribution pipe and prevents the plurality of suction pipes from interfering with degassing of the liquid.

[0015] [7] In the degassing element described in [6] above, the plurality of suction pipes may be arranged at equal intervals in the circumferential direction of the liquid distribution pipe. In this degassing element, the plurality of suction pipes are arranged at equal intervals in the circumferential direction of the liquid distribution pipe. Therefore, the hollow portions of the plurality of hollow fiber membranes and the hollow portions of the plurality of suction pipes are connected at either the first element end or the second element end, and when suction is applied to the hollow portions of the plurality of hollow fiber membranes and the hollow portions of the plurality of suction pipes at the other of the first element end or the second element end, variation in degassing performance among the plurality of hollow fiber membranes can be reduced.

[0016] [8] The degassing element according to any one of [1] to [7] above may further include an intermediate baffle that blocks the hollow portion of the liquid distribution pipe in an element intermediate section between the first element end and the second element end. In this degassing element, the hollow portion of the liquid distribution pipe is blocked by the intermediate baffle in the element intermediate section between the first element end and the second element end. This allows the liquid supplied to the hollow portion of the liquid distribution pipe to exit the liquid distribution pipe through the multiple openings upstream of the intermediate baffle, contact the multiple hollow fiber membranes, and then return to the liquid distribution pipe through the multiple openings downstream of the intermediate baffle. This allows the liquid to be in contact with the multiple hollow fiber membranes for a longer period of time.

[0017] [9] A degassing module according to the present disclosure comprises a degassing element according to any one of [1] to [8] above, a housing for accommodating the degassing element, a first end communication space forming section connected to an end of the first element, and a partition section that divides the area within the housing, using the plurality of hollow fiber membranes as a boundary, into an internal area including the hollow portions of the plurality of hollow fiber membranes and the hollow portion of the suction pipe, and an external area including the hollow portion of the liquid circulation pipe, wherein the first end communication space forming section forms a first end communication space that communicates between the hollow portions of the plurality of hollow fiber membranes and the hollow portion of the suction pipe, and the housing has a liquid supply port for supplying liquid to the hollow portion of the liquid circulation pipe, a liquid discharge port for discharging liquid coming out of the liquid circulation pipe, and a suction port for suctioning the internal area.

[0018] In this degassing module, the partition divides the interior of the housing, with the hollow fiber membranes as boundaries, into an internal region including the hollow portions of the hollow fiber membranes and the hollow portion of the suction pipe and an external region including the hollow portion of the liquid distribution pipe. The housing has a liquid supply port for supplying liquid to the hollow portion of the liquid distribution pipe, a liquid discharge port for discharging liquid from the liquid distribution pipe, and a suction port for suctioning the internal region. The first-end communication space forming portion connected to the first element end forms a first-end communication space that communicates the hollow portions of the hollow fiber membranes with the hollow portion of the suction pipe. Therefore, when suction is applied to the suction port, the suction force is transmitted from the hollow portion of the suction pipe to the first-end communication space, thereby suctioning the hollow portions of the hollow fiber membranes from both the second element end side and the first element end side. In other words, suction can be applied to the hollow portions of the hollow fiber membranes from both ends in the extension direction without providing suction ports for suctioning the hollow portions of the hollow fiber membranes at both the first element end and the second element end. This simplifies the structure of the degassing module, thereby improving maintainability while maintaining high degassing efficiency.

[0019]

[10] In the degassing module described in [9] above, the liquid supply port may be connected to an end of the liquid circulation pipe in the second extension direction. In this degassing module, since the liquid supply port is connected to the end of the liquid circulation pipe in the second extension direction, the liquid can be supplied to the hollow portion of the liquid circulation pipe by supplying the liquid to the liquid supply port.

[0020]

[11] The degassing module described in [9] or

[10] above may further include an end baffle that blocks the hollow portion of the liquid flow pipe at the first element end of the degassing element. In this degassing module, the end baffle blocks the hollow portion of the liquid flow pipe at the first element end. When liquid is supplied to the liquid supply port, the liquid is supplied to the hollow portion of the liquid flow pipe, exits the liquid flow pipe through the multiple openings, and is degassed by contacting the multiple hollow fiber membranes. The degassed liquid is then discharged from the liquid discharge port without returning to the hollow portion of the liquid flow pipe. In other words, the liquid does not flow in a direction that presses the multiple hollow fiber membranes against the liquid flow pipe, but rather in a direction that moves the multiple hollow fiber membranes away from the liquid flow pipe. This prevents an increase in pressure loss when the liquid passes through the multiple hollow fiber membranes, thereby preventing 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.

[0021]

[12] In the degassing module described in

[11] above, the partition may seal the gap between the second fixing part and the housing. In this degassing module, the partition seals the gap between the second fixing part and the housing, so that the internal region and the external region can be separated with a simple configuration.

[0022]

[13] In the degassing module described in [8] or [9] above, a second end communication space communicating with the hollow portions of the hollow fiber membranes and the hollow portion of the suction pipe may be formed on the second extension direction side of the degassing element, and the suction port may be adjacent to the second end communication space and communicate with the second end communication space. In this degassing module, a second end communication space communicating with the hollow portions of the hollow fiber membranes and the hollow portion of the suction pipe is formed on the second extension direction side of the degassing element, and the suction port is adjacent to the second end communication space and communicates with the second end communication space. This makes it possible to suction the hollow portions of the hollow fiber membranes from the suction port with a simple configuration.

[0023]

[14] In the degassing module described in

[13] above, the degassing element may have an intermediate baffle that blocks the hollow portion of the liquid distribution pipe at an intermediate portion between the first element end and the second element end. In this degassing module, the intermediate baffle blocks the hollow portion of the liquid distribution pipe at an intermediate portion between the first element end and the second element end. Therefore, the liquid supplied from the liquid supply port to the hollow portion of the liquid distribution pipe is prevented from flowing in the extension direction by the intermediate baffle. Therefore, the liquid exits the liquid distribution pipe through the multiple openings upstream of the intermediate baffle, comes into contact with the multiple hollow fiber membranes, and is degassed. Finally, the liquid returns to the hollow portion of the liquid distribution pipe downstream of the intermediate baffle. This allows for a longer contact time between the liquid and the multiple hollow fiber membranes.

[0024]

[15] In the degassing module described in

[14] above, the partition may have a first sealing portion that seals between the first fixing portion and the housing and a second sealing portion that seals between the second fixing portion and the housing. In this degassing module, the partition has the first sealing portion that seals between the first fixing portion and the housing and the second sealing portion that seals between the second fixing portion and the housing, so that the internal region and the external region can be separated with a simple configuration.

[0025]

[16] In the degassing module according to

[14] or

[15] above, the liquid discharge port may be connected to an end of the liquid circulation pipe in the first extension direction. In this degassing module, since the liquid discharge port is connected to the end of the liquid circulation pipe in the first extension direction, the liquid that has flowed out of the liquid circulation pipe from the multiple openings can be returned from the multiple openings to the hollow portion of the liquid circulation pipe and then discharged from the liquid discharge port.

[0026]

[17] The degassing module described in [9] above may include a plurality of degassing elements, the plurality of degassing elements being arranged in the extension direction, and between adjacent degassing elements in the extension direction, the hollow portions of the plurality of hollow fiber membranes and the hollow portions of the suction pipes may be connected to each other, and the hollow portions of the liquid distribution pipes may be connected to each other.

[0027] In this degassing module, multiple degassing elements are arranged in the extension direction. The hollow portions of the multiple hollow fiber membranes and the hollow portions of the suction pipes are connected to each other between adjacent degassing elements in the extension direction, and the hollow portions of the liquid distribution pipes are connected to each other. Therefore, when suction is applied to the suction port, the suction force is transmitted through the hollow portions of the suction pipes of the multiple degassing elements to the first-end communication space, thereby sucking the hollow portions of the multiple hollow fiber membranes of the multiple degassing elements from both the second element end side of the second-end degassing element and the first element end side of the first-end degassing element. In other words, even without suction ports for sucking the hollow portions of the multiple hollow fiber membranes at both the first element end and the second element end of each degassing element, suction can be applied to the hollow portions of the multiple hollow fiber membranes from both ends in the extension direction. This simplifies the structure of the degassing module. Furthermore, since a large flow rate of the liquid to be degassed is possible, this module is particularly suitable for degassing seawater as the liquid.

[0028]

[18] In the degassing module described in

[17] above, the liquid supply port may be connected to an end of the liquid circulation pipe in the second extension direction of a second end degassing element that is located at the end in the second extension direction of the multiple degassing elements. In this degassing module, the liquid supply port is connected to the end of the liquid circulation pipe in the second extension direction of the second end degassing element, so that liquid can be supplied from the liquid supply port to the liquid circulation pipe with a simple configuration.

[0029]

[19] The degassing module described in

[17] or

[18] above may further include an element connection section that arranges, spaced apart in the extension direction, a first side degassing element located on the first extension direction side of adjacent degassing elements in the extension direction, and a second side degassing element located on the second extension direction side of adjacent degassing elements in the extension direction, and the element connection section may form an intermediate communication space that communicates with the hollow portions of the plurality of hollow fiber membranes of the first side degassing element and the hollow portion of the suction pipe, and the hollow portions of the plurality of hollow fiber membranes of the second side degassing element and the hollow portion of the suction pipe, and an intermediate liquid flow passage that communicates with the hollow portion of the liquid flow pipe of the first side degassing element and the hollow portion of the liquid flow pipe of the second side degassing element.

[0030] In this degassing module, of the degassing elements adjacent in the extension direction, a first degassing element located in a first extension direction and a second degassing element located in a second extension direction of the degassing elements adjacent in the extension direction are arranged to be spaced apart in the extension direction by an element connection part, and the element connection part forms an intermediate communication space communicating with the hollow portions of the plurality of hollow fiber membranes of the first degassing element and the hollow portion of the suction pipe and with the hollow portions of the plurality of hollow fiber membranes of the second degassing element and an intermediate liquid flow passage communicating with the hollow portion of the liquid flow pipe of the first degassing element and with the hollow portion of the liquid flow pipe of the second degassing element. Therefore, suction forces acting on the hollow portions of the plurality of hollow fiber membranes and the hollow portion of the suction pipe can be transmitted between the degassing elements adjacent in the extension direction, and liquid can be circulated between them. Furthermore, when the hollow fiber membranes of the second-side degassing element and the hollow fiber membranes of the suction pipe are suctioned from the suction port, the suction force is transmitted through the hollow fiber membranes of the second-side degassing element to the intermediate communicating space and the first-end communicating space, thereby enabling the hollow fiber membranes of the second-end degassing element to be suctioned from both the second element end side of the second-end degassing element and the first element end side of the first-end degassing element.

[0031]

[20] In the degassing module described in

[19] above, the element connection part may have a connecting cover connected to the second fixing part of the first degassing element and the first fixing part of the second degassing element to cover the space between the first degassing element and the second degassing element, and a connecting pipe connected to the liquid circulation pipe of the first degassing element and the liquid circulation pipe of the second degassing element. In this degassing module, the element connection part has a connecting cover connected to the second fixing part of the first degassing element and the first fixing part of the second degassing element to cover the space between the first degassing element and the second degassing element, and a connecting pipe connected to the liquid circulation pipe of the first degassing element and the liquid circulation pipe of the second degassing element. Therefore, with a simple configuration, the hollow parts of the multiple hollow fiber membranes and the hollow parts of the suction pipes between the first degassing element and the second degassing element can be connected to each other, and the hollow parts of the liquid circulation pipes can be connected to each other.

[0032]

[21] In the degassing module described in

[19] or

[20] above, the suction port may be connected to the element connection part and communicate with the intermediate communication space. In this degassing module, the suction port is connected to the element connection part and communicates with the intermediate communication space, so that the length of the discharge path for gas that has permeated the multiple hollow fiber membranes can be shortened. This allows for high degassing efficiency.

[0033]

[22] The degassing module according to any one of

[17] to

[21] above, further comprising an end baffle for closing the hollow portion of the liquid flow pipe of a first end degassing element located at the end of the plurality of degassing elements in the first extension direction, the first end communicating space forming portion being connected to the first element end of the first end degassing element located at the end of the plurality of degassing elements in the first extension direction, the first end communicating space communicating between the hollow portions of the plurality of hollow fiber membranes of the first end degassing element and the hollow portion of the suction pipe of the first end degassing element, and a second end communicating space communicating between the hollow portions of the plurality of hollow fiber membranes and the hollow portion of the suction pipe is formed on the second extension direction side of a second end degassing element located at the end of the plurality of degassing elements in the second extension direction, and the suction port may be adjacent to the second end communicating space and communicated with the second end communicating space.

[0034] In this degassing module, an end baffle closes the hollow portion of the liquid flow pipe of the first-end degassing element. The first-end communicating space forming portion is connected to the first element end of the first-end degassing element, and the first-end communicating space communicates between the hollow portions of the hollow fiber membranes of the first-end degassing element and the hollow portion of the suction pipe of the first-end degassing element. Therefore, when liquid is supplied to the liquid supply port, the liquid is supplied to the hollow portion of the liquid flow pipe in the multiple degassing units, exits the liquid flow pipe through the multiple openings, and comes into contact with the multiple hollow fiber membranes to be degassed. The liquid degassed by coming into contact with the multiple hollow fiber membranes is then discharged from the liquid discharge port without returning to the hollow portion of the liquid flow pipe. In this degassing module, a second-end communicating space is formed on the second extension direction side of the second-end degassing element, communicating with the hollow portions of the hollow fiber membranes and the hollow portion of the suction pipe. The suction port is adjacent to the second-end communicating space and communicates with the second-end communicating space. Therefore, the hollow portions of the hollow fiber membranes of the degassing elements can be sucked from both the second element end side of the second end degassing element and the first element end side of the first end degassing element.

[0035]

[23] In the degassing module described in

[22] above, the housing may have a first-end suction port connected to the first-end communication space forming portion and communicating with the first-end communication space. In this degassing module, since the housing has a first-end suction port connected to the first-end communication space forming portion and communicating with the first-end communication space, high degassing efficiency can be achieved. Moreover, since the length of the discharge path for gas that has permeated the multiple hollow fiber membranes can be shortened, even higher degassing efficiency can be achieved.

[0036]

[24] In the degassing module described in

[22] or

[23] above, the partition may seal between the second fixing portion of the second-end degassing element and the housing. In this degassing module, the partition seals between the second fixing portion of the second-end degassing element and the housing, so that the internal region and the external region can be separated with a simple configuration.

[0037]

[25] In the degassing module described in any one of

[17] to

[21] above, each of the plurality of degassing elements has an intermediate baffle that closes the hollow portion of the liquid flow pipe in the element intermediate portion between the first element end and the second element end, the first end communicating space forming portion is connected to the first element end of the first end degassing element located at the end of the plurality of degassing elements in the first extension direction, the first end communicating space communicates between the hollow portions of the plurality of hollow fiber membranes of the first end degassing element and the hollow portion of the suction pipe of the first end degassing element, and a second end communicating space that communicates with the hollow portions of the plurality of hollow fiber membranes and the hollow portion of the suction pipe is formed on the second extension direction side of the second end degassing element located at the end of the plurality of degassing elements in the second extension direction, and the suction port may be adjacent to the second end communicating space and communicated with the second end communicating space.

[0038] In this degassing module, each of the multiple degassing elements has an intermediate baffle that blocks the hollow portion of the liquid distribution pipe in the element intermediate section between the first element end and the second element end. Therefore, in each degassing element, the liquid supplied to the liquid supply port is prevented from flowing in the extension direction by the intermediate baffle, so that the liquid exits the liquid distribution pipe through the multiple openings upstream of the intermediate baffle, comes into contact with the multiple hollow fiber membranes, is degassed, and returns to the hollow portion of the liquid distribution pipe downstream of the intermediate baffle. This allows for a longer contact time between the liquid and the multiple hollow fiber membranes. In this degassing module, the first-end communication space forming portion is connected to the first element end of the first-end degassing element, the first-end communication space communicates between the hollow portions of the hollow fiber membranes of the first-end degassing element and the hollow portion of the suction pipe of the first-end degassing element, a second-end communication space is formed on the second extension direction side of the second-end degassing element that communicates with the hollow portions of the hollow fiber membranes and the hollow portion of the suction pipe, and a suction port is adjacent to the second-end communication space and communicates with the second-end communication space, so that the hollow portions of the hollow fiber membranes of the multiple degassing elements can be sucked from both the second element end side of the second-end degassing element and the first element end side of the first-end degassing element.

[0039]

[26] In the degassing module described in

[25] above, the partition portion may have a first sealing portion that seals between the housing and the first fixing portion of the first side degassing element located on the first extension direction side of the degassing elements adjacent to each other in the extension direction, a second sealing portion that seals between the housing and the second fixing portion of the first side degassing element, a third sealing portion that seals between the housing and the first fixing portion of the second side degassing element located on the second extension direction side of the degassing elements adjacent to each other in the extension direction, and a fourth sealing portion that seals between the housing and the second fixing portion of the second side degassing element. In this degassing module, the partition has a first sealing portion that seals between the first fixing portion of the first side degassing element and the housing, a second sealing portion that seals between the second fixing portion of the first side degassing element and the housing, a third sealing portion that seals between the first fixing portion of the second side degassing element and the housing, and a fourth sealing portion that seals between the second fixing portion of the second side degassing element and the housing, so that the internal area and the external area can be separated with a simple configuration.

[0040]

[27] In the degassing module according to

[25] or

[26] , the liquid discharge port may be connected to an end of the liquid circulation pipe in the first extension direction of a first end degassing element that is located at the end in the first extension direction of the multiple degassing elements. In this degassing module, since the liquid discharge port is connected to the end of the liquid circulation pipe in the first extension direction of the first end degassing element, the liquid that has come out of the liquid circulation pipe from the multiple openings can be returned from the multiple openings to the hollow portion of the liquid circulation pipe and then discharged from the liquid discharge port.

[0041]

[28] In the degassing module according to any one of [9] to

[27] above, the housing has a cylindrical portion in which the degassing element is accommodated, a first cover portion connected to one end of the cylindrical portion and having a liquid discharge port, and a second cover portion connected to the end of the cylindrical portion opposite the first cover portion and having a liquid supply port, and at least one of the first cover portion and the second cover portion may have a suction port. In this degassing module, the housing has a cylindrical portion in which the degassing element is accommodated, a first cover portion connected to one end of the cylindrical portion and having a liquid discharge port, and a second cover portion connected to the end of the cylindrical portion opposite the first cover portion and having a liquid supply port, and at least one of the first cover portion and the second cover portion has a suction port. This makes it possible to easily manufacture the degassing module.

[0042]

[29] The method for degassing a liquid according to the present disclosure is a method for degassing a liquid using a degassing module described in any one of [9] to

[28] above, in which the suction port of the degassing module is sucked and the liquid is supplied to the liquid supply port of the degassing module.

[0043] In this liquid degassing method, in any of the above degassing modules, when suction is applied to the suction port, the suction force is transmitted through the hollow part of the suction pipe to the first end communicating space, thereby sucking the hollow parts of the plurality of hollow fiber membranes from both the second element end side and the first element end side. Then, by supplying liquid to the liquid supply port, the liquid is forced out of the liquid distribution pipe through the plurality of openings, brought into contact with the plurality of hollow fiber membranes, degassed, and discharged from the liquid discharge port. [Effects of the Invention]

[0044] According to the present disclosure, it is possible to improve maintainability while maintaining high degassing efficiency. [Brief explanation of the drawings]

[0045] [Figure 1] FIG. 2 is a schematic front view of the degassing element according to the first embodiment. [Figure 2]FIG. 2 is a schematic plan view of the degassing element shown in FIG. [Figure 3] FIG. 2 is a schematic cross-sectional view taken along line III-III shown in FIG. [Figure 4] FIG. 2 is a schematic cross-sectional view taken along line IV-IV shown in FIG. [Figure 5] FIG. 2 is a schematic cross-sectional view showing a part of the degassing element shown in FIG. [Figure 6] FIG. 2 is a schematic cross-sectional view showing a part of the degassing element shown in FIG. [Figure 7] FIG. 2 is a schematic cross-sectional view of the degassing module according to the first embodiment. [Figure 8] FIG. 8 is a schematic cross-sectional view of the degassing module shown in FIG. 7. [Figure 9] FIG. 8 is a schematic cross-sectional view showing a part of the degassing module shown in FIG. [Figure 10] FIG. 8 is a schematic cross-sectional view showing a part of the degassing module shown in FIG. [Figure 11] FIG. 10 is a schematic cross-sectional view of a degassing module according to a second embodiment. [Figure 12] FIG. 12 is a schematic cross-sectional view of the degassing module shown in FIG. [Figure 13] FIG. 10 is a schematic cross-sectional view of a degassing module according to a third embodiment. [Figure 14] FIG. 14 is a schematic cross-sectional view of the degassing module shown in FIG. [Figure 15] FIG. 10 is a schematic cross-sectional view of a degassing module according to a fourth embodiment. [Figure 16] FIG. 16 is a schematic cross-sectional view of the degassing module shown in FIG. [Figure 17] FIG. 10 is a schematic cross-sectional view of a degassing module according to a fifth embodiment. [Figure 18] FIG. 6 is a schematic front view of a degassing element according to a second embodiment. [Figure 19] FIG. 19 is a schematic cross-sectional view taken along line XIX-XIX shown in FIG. [Figure 20] FIG. 19 is a schematic cross-sectional view showing a part of the degassing element shown in FIG. 18. [Figure 21]FIG. 10 is a schematic cross-sectional view of a degassing module according to a sixth embodiment. [Figure 22] FIG. 22 is a schematic cross-sectional view showing the degassing element shown in FIG. 21. [Figure 23] FIG. 22 is a schematic cross-sectional view showing a part of the degassing element shown in FIG. 21. [Figure 24] FIG. 22 is a schematic cross-sectional view showing a part of the degassing element shown in FIG. 21. [Figure 25] FIG. 22 is a schematic cross-sectional view showing a part of the degassing element shown in FIG. 21. [Figure 26] FIG. 13 is a schematic cross-sectional view of a degassing module according to a seventh embodiment. [Figure 27] FIG. 27 is a schematic cross-sectional view showing the degassing element shown in FIG. 26. DETAILED DESCRIPTION OF THE INVENTION

[0046] Hereinafter, a degassing element, a degassing module, and a liquid degassing method according to embodiments 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 duplicated explanations will be omitted.

[0047] [Degassing element according to the first embodiment] FIG. 1 is a schematic front view of a degassing element according to a first embodiment. FIG. 2 is a schematic plan view of the degassing element shown in FIG. 1. FIG. 3 is a schematic cross-sectional view taken along line III-III in FIG. 1. FIG. 4 is a schematic cross-sectional view taken along line IV-IV in FIG. 1. FIG. 5 is a schematic cross-sectional view showing a portion of the degassing element shown in FIG. 1. FIG. 6 is a schematic cross-sectional view showing a portion of the degassing element shown in FIG. 1. As shown in FIGS. 1 to 6, a degassing element 2 according to this embodiment is used to degas a liquid L and is incorporated into, for example, a degassing module, which will be described later. The liquid L 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 element 2 includes a liquid distribution pipe 21, a plurality of hollow fiber membranes 22, a plurality of suction pipes 23, a first fixing portion 24, and a second fixing portion 25.

[0048] The liquid circulation pipe 21 is a cylindrical member extending in an extension direction D. One of the two extension directions D is referred to as a first extension direction D1, and the other is referred to as a second extension direction D2. In FIG. 3, the upper side is the first extension direction D1, and the lower side is the second extension direction D2. The end of the degassing element 2 on the first extension direction D1 side is referred to as a first element end 2a, and the end of the degassing element 2 on the second extension direction D2 side is referred to as a second element end 2b.

[0049] The hollow portion 21a of the liquid circulation pipe 21 is a flow path (internal flow path) through which the liquid L can flow, and is defined 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 D 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 D1 to the end of the degassing element 2 in the second extension direction D2. The hollow portion 21a of the liquid circulation pipe 21 is open in the first extension direction D1 and the second extension direction D2. The opening of the hollow portion 21a of the liquid circulation pipe 21 at the first element end 2a, i.e., the opening on the first extension direction D1 side of the hollow portion 21a of the liquid circulation pipe 21, is referred to as a first-end liquid circulation pipe opening 21b. The opening of the hollow portion 21a of the liquid circulation pipe 21 at the second element end 2b, i.e., the opening on the second extension direction D2 side of the hollow portion 21a of the liquid circulation pipe 21, is referred to as a second-end liquid circulation pipe opening 21c. In the degassing element 2, the hollow portion 21a of the liquid circulation pipe 21 is not provided with a member such as a baffle for preventing the liquid L from moving in the extending direction D.

[0050] 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 hollow portion 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 hollow portion 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 hollow portion 21a to the outside of the liquid circulation pipe 21.

[0051] 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 in the initial state (unused state) of the degassing element 2, the plurality of hollow fiber membranes 22 extend along the extension direction D. The plurality of hollow fiber membranes 22 form a membrane bundle that is generally cylindrical as a whole.

[0052] 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 threads are woven with warp threads (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 D and cover the plurality of openings 21d.

[0053] 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 extending direction D 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 extending direction D1 to the end of the degassing element 2 in the second extending direction D2. The hollow portions 22a of the plurality of hollow fiber membranes 22 are open in the first extending direction D1 and the second extending direction D2. The hollow portions 22a of the plurality of hollow fiber membranes 22 refer to the respective hollow portions 22a of the plurality of hollow fiber membranes 22. The openings of the hollow portions 22a of the plurality of hollow fiber membranes 22 at the first element end portion 2a, i.e., the openings of the hollow portions 22a of the plurality of hollow fiber membranes 22 on the first extending direction D1 side, are referred to as first end hollow fiber membrane openings 22b. The openings of the hollow portions 22a of the hollow fiber membranes 22 at the second element end 2b, that is, the openings of the hollow portions 22a of the hollow fiber membranes 22 on the second extending direction D2 side, are referred to as second end hollow fiber membrane openings 22c.

[0054] The hollow fiber membrane 22 is a hollow fiber membrane that allows gas G to pass through but not liquid L to pass through. 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 porosity. 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. 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.

[0055] 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, 500 μm or less, preferably 350 μm or less, and more preferably 250 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 150 μm or more, and more preferably 200 μm or more.

[0056] The suction pipe 23 extends along the liquid circulation pipe 21. The suction pipe 23 extending along the liquid circulation pipe 21 means that the suction pipe 23 extends along the extension direction D when the degassing element 2 is in its initial state (unused state).

[0057] The plurality of suction pipes 23 are arranged outside the plurality of hollow fiber membranes 22. The outside of the plurality of hollow fiber membranes 22 refers to the side of the plurality of hollow fiber membranes 22 opposite the liquid distribution pipe 21. In other words, the plurality of suction pipes 23 are arranged around the plurality of hollow fiber membranes 22. The plurality of suction pipes 23 are also arranged at equal intervals in the circumferential direction of the liquid distribution pipe 21.

[0058] The hollow portion 23a of the suction pipe 23 is a flow path (internal flow path in a pipe) through which the gas G can flow, and is formed by the inner circumferential surface of the suction pipe 23. The multiple suction pipes 23 extend over the entire area in the extension direction D of the degassing element 2. That is, the multiple suction pipes 23 extend from the end of the degassing element 2 in the first extension direction D1 to the end of the degassing element 2 in the second extension direction D2. The hollow portions 23a of the multiple suction pipes 23 are open in the first extension direction D1 and the second extension direction D2. Note that the hollow portions 23a of the multiple suction pipes 23 refer to the respective hollow portions 23a of the multiple suction pipes 23. The openings of the hollow portions 23a of the multiple suction pipes 23 at the first element end 2a, i.e., the openings of the hollow portions 23a of the multiple suction pipes 23 on the first extension direction D1 side, are referred to as first-end suction pipe openings 23b. The openings of the hollow portions 23a of the suction pipes 23 at the second element end 2b, that is, the openings of the hollow portions 23a of the suction pipes 23 on the second extending direction D2 side, are referred to as second end suction pipe openings 23c.

[0059] The total cross-sectional area of ​​the hollow portions 23a of the multiple suction pipes 23 is larger than the total cross-sectional area of ​​the hollow portions 22a of the multiple hollow fiber membranes 22. The cross-sectional area of ​​the hollow portion 23a of each suction pipe 23 is the area of ​​the hollow portion 23a in a cross section perpendicular to the central axis of each suction pipe 23 along each suction pipe 23. The total cross-sectional area of ​​the hollow portions 23a of the multiple suction pipes 23 is the sum of the cross-sectional areas of the hollow portions 23a of each suction pipe 23. The cross-sectional area of ​​the hollow portion 22a of each hollow fiber membrane 22 is the area of ​​the hollow portion 22a in a cross section perpendicular to the central axis of each hollow fiber membrane 22 along each hollow fiber membrane 22. The total cross-sectional area of ​​the hollow portions 22a of the multiple hollow fiber membranes 22 is the sum of the cross-sectional areas of the hollow portions 22a of each hollow fiber membrane 22.

[0060] The first fixing part 24 is located at the first element end part 2a, and fixes the plurality of hollow fiber membranes 22 and the plurality of suction pipes 23 to the liquid distribution pipe 21 so as to seal the gaps between the liquid distribution pipe 21, the plurality of hollow fiber membranes 22, and the suction pipe 23, and to leave the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 open. In other words, the first fixing part 24 fixes the ends of the plurality of hollow fiber membranes 22 and the plurality of suction pipes 23 on the first extension direction D1 side to the liquid distribution pipe 21. The first fixing part 24 also seals the gaps between the liquid distribution pipe 21, the plurality of hollow fiber membranes 22, and the plurality of suction pipes 23. Furthermore, the first fixing portion 24 is not provided in the hollow portion 21a of the liquid circulation pipe 21, the hollow portions 22a of the plurality of hollow fiber membranes 22, and the hollow portions 23a of the plurality of suction pipes 23, thereby opening the hollow portion 21a of the liquid circulation pipe 21, the hollow portions 22a of the plurality of hollow fiber membranes 22, and the hollow portions 23a of the plurality of suction pipes 23. The first fixing portion 24 is formed, for example, from a resin.

[0061] The second fixing part 25 is located at the second element end part 2b, and fixes the plurality of hollow fiber membranes 22 and the plurality of suction pipes 23 to the liquid distribution pipe 21 so as to seal the gaps between the liquid distribution pipe 21, the plurality of hollow fiber membranes 22, and the suction pipe 23, and to leave the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 open. In other words, the second fixing part 25 fixes the ends of the plurality of hollow fiber membranes 22 and the plurality of suction pipes 23 on the second extending direction D2 side to the liquid distribution pipe 21. The second fixing part 25 also seals the gaps between the liquid distribution pipe 21, the plurality of hollow fiber membranes 22, and the plurality of suction pipes 23. Furthermore, the second fixing portion 25 is not provided in the hollow portion 21a of the liquid circulation pipe 21, the hollow portions 22a of the plurality of hollow fiber membranes 22, and the hollow portions 23a of the plurality of suction pipes 23, thereby opening the hollow portion 21a of the liquid circulation pipe 21, the hollow portions 22a of the plurality of hollow fiber membranes 22, and the hollow portions 23a of the plurality of suction pipes 23. The second fixing portion 25 is formed, for example, from a resin.

[0062] The plurality of hollow fiber membranes 22 and the plurality of suction pipes 23 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.

[0063] As described above, in the degassing element 2 according to this embodiment, the plurality of hollow fiber membranes 22 extending along the liquid distribution pipe 21 are arranged around the liquid distribution pipe 21 so as to cover the plurality of openings 21d. Therefore, when the hollow portions 22a of the plurality of hollow fiber membranes 22 are suctioned and the liquid L is supplied to the liquid distribution pipe 21, the liquid L exits the liquid distribution pipe 21 through the plurality of openings 21d and comes into contact with the plurality of hollow fiber membranes 22, thereby being degassed. Here, the degassing element 2 includes a plurality of suction pipes 23 extending along the liquid distribution pipe 21. Furthermore, the first fixing portion 24 located at the first element end portion 2a fixes the plurality of hollow fiber membranes 22 and the plurality of suction pipes 23 to the liquid distribution pipe 21 so as to seal the gaps between the liquid distribution pipe 21, the plurality of hollow fiber membranes 22, and the plurality of suction pipes 23, thereby leaving the hollow portions 21a of the liquid distribution pipe 21, the hollow portions 22a of the plurality of hollow fiber membranes 22, and the hollow portions 23a of the plurality of suction pipes 23 open. In addition, the second fixing portion 25 located at the second element end portion 2b fixes the plurality of hollow fiber membranes 22 and the plurality of suction pipes 23 to the liquid circulation pipe 21 so as to seal the spaces between the liquid circulation pipe 21, the plurality of hollow fiber membranes 22, and the plurality of suction pipes 23, and to open the hollow portion 21a of the liquid circulation pipe 21, the hollow portions 22a of the plurality of hollow fiber membranes 22, and the hollow portions 23a of the plurality of suction pipes 23. For this reason, the openings of the hollow portions 22a of the plurality of hollow fiber membranes 22 are communicated with the openings of the hollow portions 23a of the plurality of suction pipes 23 at either the first element end 2a or the second element end 2b, i.e., either the first end hollow fiber membrane opening 22b or the second end hollow fiber membrane opening 22c is communicated with either the first end suction pipe opening 23b or the second end suction pipe opening 23c, and the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 are sucked from the other of either the first element end 2a or the second element end 2b. Then, this suction force is transmitted through the hollow portions 23a of the plurality of suction pipes 23, so that the hollow portions 22a of the plurality of hollow fiber membranes 22 are sucked from both the second element end 2b side and the first element end 2a side.In other words, even if suction ports for sucking the hollow portions 22a of the plurality of hollow fiber membranes 22 are not provided at both the first element end 2a and the second element end 2b, the hollow portions 22a of the plurality of hollow fiber membranes 22 can be sucked from both ends in the extending direction D. This simplifies the structure of the degassing module using the degassing element 2, thereby improving maintainability while maintaining high degassing efficiency.

[0064] Furthermore, since the degassing element 2 is provided with a plurality of suction pipes 23, the suction force can be transmitted more easily.

[0065] Furthermore, in this degassing element 2, the total cross-sectional area of ​​the hollow portions 23a of the plurality of suction pipes 23 is larger than the total cross-sectional area of ​​the hollow portions 22a of the plurality of hollow fiber membranes 22, and therefore the pressure loss (suction loss) caused by suction in the hollow portions 23a of the plurality of suction pipes 23 can be made smaller than the pressure loss (suction loss) caused by suction in the hollow portions 22a of the plurality of hollow fiber membranes 22. As a result, the hollow portions 22a of the plurality of hollow fiber membranes 22 are communicated with the hollow portions 23a of the plurality of suction pipes 23 at either the first element end 2a or the second element end 2b, and when suction is applied to the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 at the other of the first element end 2a or the second element end 2b, the hollow portions 22a of the plurality of hollow fiber membranes 22 can be easily suctioned from either the first element end 2a or the second element end 2b.

[0066] Furthermore, in this degassing element 2, the multiple suction pipes 23 are arranged outside the multiple hollow fiber membranes 22, making it easier to arrange the multiple hollow fiber membranes 22 around the liquid circulation pipe 21 and preventing the multiple suction pipes 23 from hindering degassing of the liquid L.

[0067] Furthermore, in this degassing element 2, multiple suction pipes 23 are arranged around multiple hollow fiber membranes 22, making it easier to arrange multiple hollow fiber membranes 22 around the liquid circulation pipe 21 and preventing the multiple suction pipes 23 from hindering degassing of the liquid L.

[0068] Furthermore, in this degassing element 2, the plurality of suction pipes 23 are arranged at equal intervals in the circumferential direction of the liquid distribution pipe 21. Therefore, the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 are communicated with each other at either the first element end 2a or the second element end 2b, and this makes it possible to reduce variation in degassing performance among the plurality of hollow fiber membranes 22 when suction is applied to the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 at the other of the first element end 2a or the second element end 2b.

[0069] [Degassing module according to the first embodiment] FIG. 7 is a schematic cross-sectional view of a degassing module according to the first embodiment. FIG. 8 is a schematic cross-sectional view of the degassing module shown in FIG. 7. FIG. 9 is a schematic cross-sectional view showing a portion of the degassing module shown in FIG. 7. FIG. 10 is a schematic cross-sectional view showing a portion of the degassing module shown in FIG. 7. As shown in FIGS. 7 to 10, the degassing module 1 according to this embodiment is a module for degassing a liquid L. The degassing module 1 includes the degassing element 2 according to the first embodiment described above, a housing 3, an end baffle 4, a first end communicating space forming portion 5, and a partition portion 6. Note that in FIG. 7, only the housing 3 is shown in cross section.

[0070] The housing 3 accommodates the degassing element 2 so that a space is formed between the degassing element 2. This space is a space between the degassing element 2 and the housing 3 through which the liquid L can flow.

[0071] The housing 3 includes a cylindrical portion 31 in which the degassing element 2 is accommodated, a first lid portion 32 connected to one end of the cylindrical portion 31, and a second lid portion 33 connected to the end of the cylindrical portion 31 opposite the first lid portion 32. The degassing element 2 is accommodated in the cylindrical portion 31 so that the extending direction D of the degassing element 2 is the extending direction of the cylindrical portion 31, i.e., the opposing direction of the first lid portion 32 and the second lid portion 33. As a result, the extending direction D of the degassing element 2 and the extending direction of the cylindrical portion 31 are the same direction, and therefore the extending direction of the cylindrical portion 31 is also referred to as the extending direction D. The first lid portion 32 is connected to the end of the cylindrical portion 31 on the first extending direction D1 side so as to cover the opening of the cylindrical portion 31 on the first extending direction D1 side. The second lid portion 33 is connected to the end of the cylindrical portion 31 on the second extending direction D2 side so as to cover the opening of the cylindrical portion 31 on the second extending direction D2 side.

[0072] The end baffle 4 closes the end of the hollow portion 21a of the liquid circulation pipe 21 on the first extension direction D1 side. That is, the end baffle 4 closes the hollow portion 21a of the liquid circulation pipe 21 at the first element end 2a of the degassing element 2. The end baffle 4 is fitted into the hollow portion 21a of the liquid circulation pipe 21 at the end 21f of the liquid circulation pipe 21 in the first extension direction D1. That is, the end baffle 4 is fitted into the end of the hollow portion 21a of the liquid circulation pipe 21 on the first extension direction D1 side. The end baffle 4 prevents the liquid L supplied to the hollow portion 21a of the liquid circulation pipe 21 from being discharged in the first extension direction D1. Therefore, the liquid L supplied to the hollow portion 21a of the liquid circulation pipe 21 is discharged radially outward from the liquid circulation pipe 21 through the multiple openings 21d formed in the liquid circulation pipe 21 without being discharged in the first extension direction D1.

[0073] The first end communication space forming portion 5 is connected to the first element end portion 2a to form a first end communication space S1. The first end communication space S1 is a space that communicates the hollow portions 22a of the multiple hollow fiber membranes 22 with the hollow portions 23a of the multiple suction pipes 23. The first end communication space S1 is a space adjacent to the side of the degassing element 2 in the first extension direction D1. The first end communication space S1 is also a space adjacent to the first end hollow fiber membrane openings 22b and the first end suction pipe openings 23b. The first end communication space forming portion 5 is connected to the first fixing portion 24 of the degassing element 2 so as to cover the first element end portion 2a. The first end communication space forming portion 5 forms a first end communication space S1 between itself and the first element end portion 2a.

[0074] The partition 6 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 and the hollow portions 23a of the plurality of suction pipes 23. The outer area R2 is an area including the hollow portions 21a of the liquid distribution pipes 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 hollow portion 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 hollow portion 21a of the liquid flow pipe 21.

[0075] The partition 6 seals the gap between the second fixing portion 25 of the degassing element 2 and the housing 3. Therefore, a second end communication space S3 that communicates with the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 is formed on the second extending direction D2 side of the degassing element 2. The second end communication space S3 is a space adjacent to the second element end portion 2b on the second extending direction D2 side. The second end communication space S3 is also a space adjacent to the second end hollow fiber membrane openings 22c and the second end suction pipe openings 23c. The second end communication space S3 is also part of the internal region R1 because it communicates with the hollow portions 22a of the plurality of hollow fiber membranes 22.

[0076] Moreover, the partition 6 seals the gap between the second fixing portion 25 of the degassing element 2 and the housing 3, thereby fixing the second fixing portion 25 of the degassing element 2 to the housing 3. The partition 6 is formed, for example, from resin.

[0077] The housing 3 has a liquid supply port 3a for supplying the liquid L to the hollow portion 21a of the liquid circulation pipe 21, a liquid discharge port 3b for discharging the liquid L that has come out of the hollow portion 21a of the liquid circulation pipe 21, and a suction port 3c for sucking (evacuating) the internal region R1. The suction port 3c is also called a vacuum port, etc. The liquid supply port 3a, the liquid discharge port 3b, and the suction port 3c may be configured integrally with the housing 3 or may be separate members from the housing 3.

[0078] The liquid supply port 3a 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 3a 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 side in the second extension direction D2. The liquid supply port 3a is in communication with the hollow portion 21a of the liquid circulation pipe 21.

[0079] The liquid discharge port 3b is provided in the first cover portion 32 and is a port that communicates between the inside and the outside of the housing 3. The liquid discharge port 3b is adjacent to the space S2 outside the liquid circulation pipe 21 and is in communication with the space S2 outside the liquid circulation pipe 21.

[0080] The suction port 3c is provided in the second cover portion 33 and is a port that communicates between the inside and outside of the housing 3. The suction port 3c is adjacent to the second end communicating space S3 and is communicated with the second end communicating space S3.

[0081] [Method for degassing liquid according to the first embodiment] Next, a description will be given of a liquid degassing method according to the first embodiment. The liquid degassing method according to the first embodiment is a method for degassing a liquid L using a degassing module 1.

[0082] In this degassing method, the suction port 3c of the degassing module 1 is suctioned, and liquid L is supplied to the liquid supply port 3a of the degassing module 1. Suction of the suction port 3c can be performed, for example, by connecting a suction device (not shown) such as a vacuum pump to the suction port 3c via piping or the like and activating this suction device. Supply of liquid L to the liquid supply port 3a can be performed, for example, by connecting a liquid supply device (not shown) such as a liquid feed pump that sends out liquid L via piping or the like to the liquid supply port 3a and activating this liquid supply device.

[0083] When the suction port 3c is suctioned, the internal region R1 connected to the suction port 3c is suctioned, and the internal region R1 is depressurized. Furthermore, when the liquid L is supplied to the liquid supply port 3a, the liquid L is supplied to the external region R2 connected to the liquid supply port 3a. The liquid L supplied to the liquid supply port 3a is supplied to the hollow portion 21a of the liquid circulation pipe 21 and discharged from the multiple openings 21d of the liquid circulation pipe 21 into the space S2 outside the liquid circulation pipe 21, where it comes into contact with the multiple hollow fiber membranes 22. At this time, the hollow portions 22a of the multiple hollow fiber membranes 22 are depressurized, so that gas G, such as dissolved gas in the liquid L and air bubbles contained in the liquid L, permeates the multiple hollow fiber membranes 22. This degasses the liquid L. The degassed liquid L passes through the space between the degassing element 2 and the housing 3 and is discharged from the liquid discharge port 3b. 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 S1, the hollow portions 23a of the multiple suction pipes 23, and the second end communicating space S3, and is discharged from the suction port 3c.

[0084] As described above, in the degassing module 1 according to this embodiment, the end baffle 4 closes the hollow portion 21a of the liquid circulation pipe 21 at the first element end 2a, and the first end communication space forming portion 5 forms a first end communication space S1 that communicates between the first end hollow fiber membrane openings 22b of the hollow portions 22a of the plurality of hollow fiber membranes 22 at the second element end 2b and the first end suction pipe openings 23b of the hollow portions 23a of the plurality of suction pipes 23 at the second element end 2b. 6 divides the area inside the housing 3 into an inner area R1 including the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23, and an outer area R2 including the hollow portions 21a of the liquid circulation pipes 21, and the housing 3 has a liquid supply port 3a for supplying the liquid L to the hollow portions 21a of the liquid circulation pipes 21, a liquid discharge port 3b for discharging the liquid L discharged from the liquid circulation pipes 21, and a suction port 3c for suctioning the inner area R1. Therefore, when suction is applied to the suction port 3c, the suction force is transmitted to the first end communicating space S1 through the hollow portions 23a of the plurality of suction pipes 23, and the hollow portions 22a of the plurality of hollow fiber membranes 22 are sucked from both the second element end 2b side and the first element end 2a side. In other words, even if suction ports for sucking the hollow portions 22a of the plurality of hollow fiber membranes 22 are not provided at both the first element end 2a and the second element end 2b, the hollow portions 22a of the plurality of hollow fiber membranes 22 can be sucked from both ends in the extending direction D. This simplifies the structure of the degassing module 1, thereby improving maintainability while maintaining high degassing efficiency.

[0085] Furthermore, in this degassing module 1, the liquid supply port 3a is connected to the end 21e of the liquid circulation pipe 21 in the second extension direction D2, so that by supplying liquid L to the liquid supply port 3a, the liquid L can be supplied to the hollow portion 21a of the liquid circulation pipe 21.

[0086] Furthermore, in this degassing module 1, because the end baffle 4 blocks the hollow portion 21a of the liquid distribution pipe 21 at the first element end 2a, when liquid L is supplied to the liquid supply port 3a, the liquid L is supplied to the hollow portion 21a of the liquid distribution pipe 21, exits the liquid distribution pipe 21 through the multiple openings 21d, and comes into contact with the multiple hollow fiber membranes 22 to be degassed. After that, the liquid L, which has come into contact with the multiple hollow fiber membranes 22 and been degassed, is discharged from the liquid discharge port 3b without returning to the hollow portion 21a of the liquid distribution pipe 21. In other words, the liquid L does not flow in a direction pressing the multiple hollow fiber membranes 22 against the liquid distribution pipe 21, but rather in a direction separating the multiple hollow fiber membranes 22 from the liquid distribution pipe 21. This suppresses an increase in pressure loss when the liquid L passes through the multiple hollow fiber membranes 22, thereby suppressing a decrease in the flow rate of the liquid L. As a result, for example, a liquid supply device with a relatively low output can be used to supply liquid L to the degassing module 1.

[0087] Furthermore, in this degassing module 1, the partition 6 seals the gap between the second fixing part 25 and the housing 3, so that the inner region R1 and the outer region R2 can be separated with a simple configuration.

[0088] Furthermore, in this degassing module 1, a second end communication space S3 that communicates with the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portion 23a of the suction pipe 23 is formed on the side of the degassing element 2 in the second extension direction D2, and the suction port 3c is adjacent to the second end communication space S3 and communicates with the second end communication space S3. Therefore, the hollow portions 22a of the plurality of hollow fiber membranes 22 can be sucked through the suction port 3c with a simple configuration.

[0089] In this degassing module 1, the housing 3 has a cylindrical portion 31 in which the degassing element 2 is housed, a first lid portion 32 connected to one end of the cylindrical portion 31 and having a liquid discharge port 3b, and a second lid portion 33 connected to the end of the cylindrical portion 31 opposite to the first lid portion 32 and having a liquid supply port 3a and a suction port 3c. This makes it possible to easily manufacture the degassing module 1.

[0090] Furthermore, in this degassing module 1, the hollow portion 21a of the liquid circulation pipe 21 is not provided with any member other than the end baffle 4 to prevent the liquid L from moving in the extension direction D. Therefore, the liquid L that comes out of the liquid circulation pipe 21 is discharged from the liquid discharge port 3b without returning to the liquid circulation pipe 21.

[0091] Consider a comparative example of a degassing module in which a baffle or other member is provided to block the hollow portion of the liquid flow pipe so that the liquid supplied to the liquid flow pipe exits the pipe and returns to the liquid flow pipe. In this comparative example of a degassing module, the liquid exiting the liquid flow pipe presses against the multiple hollow fiber membranes as it returns to the liquid flow pipe, narrowing the liquid flow path and increasing the pressure loss of the liquid. This increase in liquid pressure loss becomes more pronounced as the flow rate of the liquid increases. This reduces the flow rate of the liquid, so a high-output liquid supply device (not shown), such as a liquid delivery pump, must be used to deliver the liquid L to the degassing module.

[0092] In contrast, in this degassing module 1, other than the end baffle 4 that closes the hollow portion 21a of the liquid circulation pipe 21 at the first element end 2a, no member that blocks the movement of the liquid L in the extension direction D is provided in the hollow portion 21a of the liquid circulation pipe 21. Therefore, the liquid L that comes out of the liquid circulation pipe 21 is discharged from the liquid discharge port 3b without returning to the liquid circulation pipe 21. Therefore, compared to the degassing module of the comparative example, the pressure loss of the liquid is reduced and the flow rate of the liquid is improved, so that a liquid supply device with a relatively low output can be used.

[0093] In the liquid degassing method according to the present embodiment, when suction is applied to the suction port 3c in the degassing module 1, the suction force is transmitted to the first end communicating space S1 through the hollow portions 23a of the plurality of suction pipes 23, thereby sucking the hollow portions 22a of the plurality of hollow fiber membranes 22 from both the second element end 2b side and the first element end side. Then, by supplying the liquid L to the liquid supply port 3a, the liquid L is forced out of the liquid circulation pipe 21 through the plurality of openings 21d, brought into contact with the plurality of hollow fiber membranes 22, degassed, and discharged from the liquid discharge port 3b.

[0094] By degassing seawater as the liquid L, the carbon dioxide concentration in the seawater can be reduced, and this can reduce the carbon dioxide concentration in the atmosphere.

[0095] [Degassing module according to the second embodiment] Next, a degassing module according to a second embodiment will be described. The degassing module according to the second embodiment is basically the same as the degassing module 1 according to the first embodiment, but differs from the degassing module 1 according to the first embodiment in that it is equipped with a plurality of degassing elements 2. Therefore, in the following description, only the differences from the degassing module 1 according to the first embodiment will be described, and descriptions similar to those of the degassing module 1 according to the first embodiment will be omitted.

[0096] Fig. 11 is a schematic cross-sectional view of a degassing module according to a second embodiment. Fig. 12 is a schematic cross-sectional view of the degassing module shown in Fig. 11. As shown in Figs. 11 and 12, a degassing module 1A according to this embodiment includes multiple degassing elements 2, a housing 3A, an end baffle 4, a first end communication space forming portion 5, a partition portion 6, and an element connecting portion 7A. Note that Fig. 11 shows only the housing 3A in cross section.

[0097] The degassing elements 2 are arranged in the extension direction D. The degassing elements 2 are adjacent to each other in the extension direction D. Between the degassing elements 2 adjacent to each other in the extension direction D, the hollow portions 22a of the hollow fiber membranes 22 and the hollow portions 23a of the suction pipes 23 are connected to each other, and the hollow portions 21a of the liquid circulation pipes 21 are connected to each other. In this embodiment, the degassing elements 2 are composed of a first-end degassing element 2α located at the end in the first extension direction D1 and a second-end degassing element 2β located at the end in the second extension direction D2. In other words, the degassing module 1A includes two degassing elements. The first-end degassing element 2α is also the first-side degassing element located on the first extension direction D1 side of the two degassing elements 2 adjacent to each other in the extension direction D. The second-end degassing element 2β is also the second-side degassing element located on the second extension direction D2 side of the two degassing elements 2 adjacent to each other in the extension direction D.

[0098] The housing 3A accommodates the first-end degassing element 2α and the second-end degassing element 2β such that a space is formed between the first-end degassing element 2α and the second-end degassing element 2β. The housing 3A includes a cylindrical portion 31A in which the first-end degassing element 2α and the second-end degassing element 2β are accommodated, a first lid portion 32 connected to one end of the cylindrical portion 31A and having a liquid discharge port 3b, and a second lid portion 33 connected to the end of the cylindrical portion 31A opposite the first lid portion 32 and having a liquid supply port 3a and a suction port 3c. The first lid portion 32 is connected to the end of the cylindrical portion 31A on the first extension direction D1 side so as to cover the opening of the cylindrical portion 31A on the first extension direction D1 side. The second lid portion 33 is connected to the end of the cylindrical portion 31A on the second extension direction D2 side so as to cover the opening of the cylindrical portion 31A on the second extension direction D2 side.

[0099] The element connection portion 7A connects the first end degassing element 2α and the second end degassing element 2β. The element connection portion 7A also arranges the first end degassing element 2α and the second end degassing element 2β apart in the extension direction D.

[0100] The element connection portion 7A forms an intermediate communication space S4 and an intermediate liquid flow passage S5. The intermediate communication space S4 is a space that communicates with the hollow portions 22a of the hollow fiber membranes 22 and the hollow portions 23a of the suction pipes 23 of the first end degassing element 2α and the hollow portions 22a of the hollow fiber membranes 22 and the hollow portions 23a of the suction pipes 23 of the second end degassing element 2β. The intermediate communication space S4 is a space adjacent to the second end hollow fiber membrane openings 22c and the second end suction pipe openings 23c of the first end degassing element 2α and the first end hollow fiber membrane openings 22b and the first end suction pipe openings 23b of the second end degassing element 2β. The intermediate liquid flow passage S5 is a liquid flow passage that communicates with the hollow portions 21a of the liquid flow pipes 21 of the first end degassing element 2α and the hollow portions 21a of the liquid flow pipes 21 of the second end degassing element 2β. The intermediate liquid flow passage S5 is a liquid flow passage adjacent to the second end liquid flow pipe opening 21c of the first end degassing element 2α and the first end liquid flow pipe opening 21b of the second end degassing element 2β.

[0101] The element connection portion 7A has a connection cover 71A and a connection pipe 72A.

[0102] The connecting cover 71A is connected to the second fixing portion 25 of the first-end degassing element 2α and the first fixing portion 24 of the second-end degassing element 2β, and is a cover that covers the space between the first-end degassing element 2α and the second-end degassing element 2β. The second fixing portion 25 of the first-end degassing element 2α is fitted into the connecting cover 71A, thereby connecting the connecting cover 71A to the second fixing portion 25 of the first-end degassing element 2α. Furthermore, the connecting cover 71A is connected to the first fixing portion 24 of the second-end degassing element 2β by fitting the first fixing portion 24 of the second-end degassing element 2β into the connecting cover 71A.

[0103] The connecting pipe 72A is a pipe that connects the liquid circulation pipe 21 of the first-end degassing element 2α and the liquid circulation pipe 21 of the second-end degassing element 2β. The end of the connecting pipe 72A in the first extension direction D1 is fitted into the liquid circulation pipe 21 of the first-end degassing element 2α, thereby connecting to the liquid circulation pipe 21 of the first-end degassing element 2α. Furthermore, the connecting pipe 72A is connected to the liquid circulation pipe 21 of the second-end degassing element 2β by fitting the end of the connecting pipe 72A in the second extension direction D2 into the liquid circulation pipe 21 of the second-end degassing element 2β.

[0104] An intermediate liquid flow passage S5 is formed by the connecting pipe 72A, which connects the hollow portions 21a of the liquid flow pipes 21 of the first-end degassing element 2α to the hollow portions 21a of the liquid flow pipes 21 of the second-end degassing element 2β. An intermediate communication space S4 is formed by the connecting cover 71A and the connecting pipe 72A, which connects the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 of the first-end degassing element 2α to the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 of the second-end degassing element 2β.

[0105] The end baffle 4 closes the end of the hollow portion 22a of the liquid circulation pipe 21 of the first-end degassing element 2α on the first extension direction D1 side. That is, the end baffle 4 closes the hollow portion 21a at the end 21f of the liquid circulation pipe 21 of the first-end degassing element 2α on the first extension direction D1 side. The end baffle 4 is fitted into the end of the hollow portion 21a of the liquid circulation pipe 21 of the first-end degassing element 2α on the first extension direction D1 side. The end baffle 4 is attached only to the first-end degassing element 2α and does not close the hollow portion 22a of the liquid circulation pipe 21 of the second-end degassing element 2β. Therefore, the liquid L is not discharged in the first extension direction D1 from the second-end degassing element 2β, but is discharged radially outward from the liquid circulation pipe 21 through the multiple openings 21d formed in the liquid circulation pipe 21 in the first-end degassing element 2α and the second-end degassing element 2β.

[0106] In addition, no components other than the end baffle 4 are provided in the hollow portion 21a and intermediate communication space S4 of the liquid flow pipe 21 of the first end degassing element 2α and the second end degassing element 2β to prevent the movement of the liquid L in the extension direction D.

[0107] The first-end communicating space forming portion 5 is connected to the first fixing portion 24 of the first-end degassing element 2α so as to cover the first element end portion 2a of the first-end degassing element 2α. The first-end communicating space forming portion 5 forms a first-end communicating space S1, which connects the hollow portions 22a of the multiple hollow fiber membranes 22 of the first-end degassing element 2α with the hollow portions 23a of the multiple suction pipes 23 of the first-end degassing element 2α. This first-end communicating space S1 is adjacent to the first-end degassing element 2α on the first extension direction D1 side. Furthermore, this first-end communicating space S1 is adjacent to the first-end hollow fiber membrane openings 22b of the multiple hollow fiber membranes 22 and the first-end suction pipe openings 23b of the multiple suction pipes 23 of the first-end degassing element 2α.

[0108] The partition 6 seals the gap between the second fixing portion 25 of the second end degassing element 2β and the housing 3A, thereby dividing the area within the housing 3A into an inner area R1 and an outer area R2. The partition 6 forms a second end communication space S3 on the second extension direction D2 side of the second end degassing element 2β that is connected to the hollow portions 22a of the multiple hollow fiber membranes 22 and the hollow portions 23a of the multiple suction pipes 23 of the second end degassing element 2β. This second end communication space S3 is a space adjacent to the second element end portion 2b of the second end degassing element 2β on the second extension direction D2 side. Furthermore, this second end communication space S3 is a space adjacent to the second end hollow fiber membrane openings 22c and the second end suction pipe openings 23c of the second end degassing element 2β.

[0109] [Method for degassing liquid according to the second embodiment] Next, a description will be given of a liquid degassing method according to the second embodiment. The liquid degassing method according to the second embodiment is a method for degassing a liquid L using a degassing module 1A.

[0110] In this degassing method, the suction port 3c of the degassing module 1A is suctioned, and the liquid L is supplied to the liquid supply port 3a of the degassing module 1A.

[0111] When suction is applied to the suction port 3c, the internal region R1 connected to the suction port 3c is suctioned, and the internal region R1 is decompressed. Furthermore, by supplying liquid L to the liquid supply port 3a, the liquid L is supplied to the external region R2 connected to the liquid supply port 3a. The liquid L supplied to the liquid supply port 3a is supplied to the hollow portions 21a of the liquid circulation pipes 21 of the second-end degassing element 2β and the first-end degassing element 2α. In the second-end degassing element 2β and the first-end degassing element 2α, the liquid L supplied to the hollow portions 21a of the liquid circulation pipes 21 is then discharged from the multiple openings 21d of the liquid circulation pipes 21 into the space S2 outside the liquid circulation pipes 21 and comes into contact with the multiple hollow fiber membranes 22. At this time, in the second end degassing element 2β and the first end degassing element 2α, the hollow portions 22a of the plurality of hollow fiber membranes 22 are in a decompressed state, so that gas G, such as dissolved gas in the liquid L and air bubbles contained in the liquid L, permeates the plurality of hollow fiber membranes 22. This degasses the liquid L. The degassed liquid L passes through the space between the second end degassing element 2β and the first end degassing element 2α and the housing 3A, and is discharged from the liquid discharge port 3b. The gas G that permeates the plurality of hollow fiber membranes 22 of the second end degassing element 2β and the first end degassing element 2α passes through the hollow portions 22a of the plurality of hollow fiber membranes 22 of the second end degassing element 2β and the first end degassing element 2α, the intermediate communicating space S4, the first end communicating space S1, the hollow portions 23a of the plurality of suction pipes 23 of the second end degassing element 2β and the first end degassing element 2α, and the second end communicating space S3, and is discharged from the suction port 3c.

[0112] As described above, in the degassing module 1A according to this embodiment, a plurality of degassing elements 2 are arranged in the extension direction, and the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 between adjacent degassing elements 2 in the extension direction are connected to one another, and the hollow portions 21a of the liquid circulation pipes 21 are connected to one another. Therefore, when suction is applied to the suction port 3c, the suction force is transmitted to the intermediate communication space S4 and the first end communication space S1 through the hollow portions 23a of the plurality of suction pipes 23 of the second end degassing element 2β and the first end degassing element 2α, and the plurality of hollow fiber membranes 22 of the first end degassing element 2α and the second end degassing element 2β are sucked from both the second element end portion 2b side of the second end degassing element 2β and the first element end portion 2a side of the first end degassing element 2α. That is, in each of the first end degassing element 2α and the second end degassing element 2β, the hollow portions 22a of the plurality of hollow fiber membranes 22 can be sucked from both ends in the extension direction D without arranging suction ports for sucking the hollow portions 22a of the plurality of hollow fiber membranes 22 at both the first element end 2a and the second element end 2b. This simplifies the structure of the degassing module 1A. Furthermore, since it is possible to increase the flow rate of the liquid L to be degassed, this is particularly suitable for degassing seawater as the liquid L.

[0113] Furthermore, in this degassing module 1A, the liquid supply port 3a is connected to the end 21e of the liquid flow pipe 21 in the second extension direction D2 of the second end degassing element 2β, so that liquid can be supplied from the liquid supply port 3a to the liquid flow pipe 21 with a simple configuration.

[0114] In addition, in this degassing module 1A, the first end degassing element 2α and the second end degassing element 2β, which are adjacent in the extension direction D, are arranged at a distance in the extension direction D by the element connection part 7A, and the element connection part 7A forms an intermediate communication space S4 that is connected to the hollow portions 22a of the multiple hollow fiber membranes 22 and the hollow portions 23a of the multiple suction pipes 23 of the first end degassing element 2α and the hollow portions 22a of the multiple hollow fiber membranes 22 and the hollow portions 23a of the multiple suction pipes 23 of the second end degassing element 2β, and an intermediate liquid flow passage S5 that is connected to the hollow portions 21a of the liquid flow pipe 21 of the first end degassing element 2α and the hollow portions 21a of the liquid flow pipe 21 of the second end degassing element 2β. Therefore, between the first end degassing element 2α and the second end degassing element 2β adjacent in the extending direction D, the suction force acting on the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 can be transmitted to each other, and the liquid L can be circulated. Moreover, when the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 of the second end degassing element 2β are suctioned from the suction port 3c, this suction force is transmitted through the hollow portions 23a of the plurality of suction pipes 23 of the first end degassing element 2α and the second end degassing element 2β to the intermediate communication space S4 and the first end communication space S1. As a result, the hollow portions 22a of the plurality of hollow fiber membranes 22 of the first end degassing element 2α and the second end degassing element 2β can be suctioned from both the second element end 2b side of the second end degassing element 2β and the first element end 2a side of the first end degassing element 2α.

[0115] Furthermore, in this degassing module 1A, the element connection part 7A is connected to the second fixing part 25 of the first-end degassing element 2α and the first fixing part 24 of the second-end degassing element 2β, and has a connecting cover 71A that covers the space between the first-end degassing element 2α and the second-end degassing element 2β, and a connecting pipe 72A that is connected to the liquid circulation pipe 21 of the first-end degassing element 2α and the liquid circulation pipe 21 of the second-end degassing element 2β. Therefore, with a simple configuration, the hollow parts 22a of the plurality of hollow fiber membranes 22 and the hollow parts 23a of the plurality of suction pipes 23 can be communicated with each other between the first-end degassing element 2α and the second-end degassing element 2β, and the hollow parts 21a of the liquid circulation pipes 21 can be communicated with each other.

[0116] In this degassing module 1A, the end baffle 4 blocks the hollow portion 21a of the liquid circulation pipe 21 of the first end degassing element 2α. The first end communication space forming portion 5 is connected to the first element end portion 2a of the first end degassing element 2α, and the first end communication space S1 communicates between the hollow portions 22a of the plurality of hollow fiber membranes 22 of the first end degassing element 2α and the hollow portions 23a of the plurality of suction pipes 23 of the first end degassing element 2α. Therefore, when liquid L is supplied to the liquid supply port 3a, the liquid L is supplied to the hollow portion 21a of the liquid circulation pipe 21 in the first end degassing element 2α and the second end degassing element 2β, exits the liquid circulation pipe 21 through the plurality of openings 21d, and comes into contact with the plurality of hollow fiber membranes 22 to be degassed. Thereafter, the liquid L that has come into contact with the plurality of hollow fiber membranes 22 and been degassed is discharged from the liquid discharge port 3b without returning to the hollow portion 21a of the liquid circulation pipe 21. In this degassing module, a second end communication space S3 that communicates with the hollow portions 22a of the multiple hollow fiber membranes 22 and the hollow portion 23a of the suction pipe 23 is formed on the second extension direction D2 side of the second end degassing element 2β, and the suction port 3c is adjacent to the second end communication space S3 and communicates with the second end communication space S3. Therefore, the hollow portions 22a of the multiple hollow fiber membranes 22 of the first end degassing element 2α and the second end degassing element 2β can be sucked from both the second element end 2b side of the second end degassing element 2β and the first element end 2a side of the first end degassing element 2α.

[0117] Furthermore, in this degassing module 1A, the partition 6 seals the gap between the second fixing portion 25 of the second end degassing element 2β and the housing 3A, so that the inner region R1 and the outer region R2 can be separated with a simple configuration.

[0118] In this degassing module 1A, the housing 3A has a cylindrical portion 31A in which the first end degassing element 2α and the second end degassing element 2β are housed, a first lid portion 32 connected to one end of the cylindrical portion 31A and having a liquid discharge port 3b, and a second lid portion 33 connected to the end of the cylindrical portion 31A opposite to the first lid portion 32 and having a liquid supply port 3a and a suction port 3c. This makes it possible to easily manufacture the degassing module 1A.

[0119] In the liquid degassing method according to the present embodiment, when suction is applied to the suction port 3c in the degassing module 1A, the suction force is transmitted to the first-end communicating space S1 through the hollow portions 23a of the plurality of suction pipes 23, thereby enabling suction to be applied to the hollow portions 22a of the plurality of hollow fiber membranes 22 in the first-end degassing element 2α and the second-end degassing element 2β from both the second element end 2b side and the first element end 2a side. By supplying liquid L to the liquid supply port 3a, the liquid L is forced out of the liquid circulation pipe 21 through the plurality of openings 21d in the first-end degassing element 2α and the second-end degassing element 2β, where it is brought into contact with the plurality of hollow fiber membranes 22, thereby being degassed, and can be discharged from the liquid discharge port 3b.

[0120] [Degassing module according to the third embodiment] Next, a degassing module according to a third embodiment will be described. The degassing module according to the third embodiment is basically the same as the degassing module 1A according to the second embodiment, but differs from the degassing module 1A according to the second embodiment in that a first-end suction port separate from the suction port is provided. Therefore, in the following description, only the differences from the degassing module 1A according to the second embodiment will be described, and descriptions similar to those of the degassing module 1A according to the second embodiment will be omitted.

[0121] Fig. 13 is a schematic cross-sectional view of a degassing module according to a third embodiment. Fig. 14 is a schematic cross-sectional view of the degassing module shown in Fig. 13. As shown in Figs. 13 and 14, a degassing module 1B according to this embodiment includes multiple degassing elements 2, a housing 3B, an end baffle 4, a first end communicating space forming portion 5B, a partition portion 6, and an element connecting portion 7A. Note that Fig. 13 shows only the housing 3B in cross section.

[0122] Similar to the first end communicating space forming portion 5 of the second embodiment, the first end communicating space forming portion 5B is connected to the first fixing portion 24 of the first end degassing element 2α so as to cover the first element end portion 2a of the first end degassing element 2α. Similarly to the first end communicating space forming portion 5 of the second embodiment, the first end communicating space forming portion 5B forms a first end communicating space S1 that communicates between the hollow portions 22a of the multiple hollow fiber membranes 22 of the first end degassing element 2α and the hollow portion 23a of the suction pipe 23 of the first end degassing element 2α. The first end communicating space forming portion 5B is formed larger than the first end communicating space forming portion 5 of the second embodiment so that the first end communicating space S1 is larger than in the second embodiment.

[0123] The housing 3B accommodates the first-end degassing element 2α and the second-end degassing element 2β so that a space is formed between the first-end degassing element 2α and the second-end degassing element 2β. The housing 3B includes a cylindrical portion 31A in which the first-end degassing element 2α and the second-end degassing element 2β are accommodated, a first cover portion 32B connected to one end of the cylindrical portion 31A and having a liquid discharge port 3b and a first-end suction port 3d, and a second cover portion 33 connected to the end of the cylindrical portion 31A opposite to the first cover portion 32B and having a liquid supply port 3a and a suction port 3c.

[0124] The first-end suction port 3d is a port provided in the first cover portion 32 that communicates between the inside and outside of the housing 3B. The first-end suction port 3d extends like a pipe from the first cover portion 32 to the inside of the housing 3B and is connected to the first-end communication space forming portion 5B. The first-end suction port 3d is communicated with the first-end communication space S1. The first-end suction port 3d may be configured integrally with the housing 3B or may be a separate member from the housing 3B.

[0125] [Method for degassing liquid according to the third embodiment] Next, a description will be given of a liquid degassing method according to the third embodiment. The liquid degassing method according to the third embodiment is a method for degassing a liquid L using a degassing module 1B.

[0126] In this degassing method, the suction port 3c and the first end suction port 3d of the degassing module 1B are suctioned, and the liquid L is supplied to the liquid supply port 3a of the degassing module 1A.

[0127] When suction is applied to the suction port 3c and the first-end suction port 3d, the internal region R1 connected to the suction port 3c and the first-end suction port 3d is suctioned, and the internal region R1 is decompressed. Furthermore, by supplying liquid L to the liquid supply port 3a, the liquid L is supplied to the external region R2 connected to the liquid supply port 3a. The liquid L supplied to the liquid supply port 3a is supplied to the hollow portions 21a of the liquid circulation pipes 21 of the second-end degassing element 2β and the first-end degassing element 2α. In the second-end degassing element 2β and the first-end degassing element 2α, the liquid L supplied to the hollow portions 21a of the liquid circulation pipes 21 is then discharged from the plurality of openings 21d of the liquid circulation pipes 21 to the outside of the liquid circulation pipes 21 and comes into contact with the plurality of hollow fiber membranes 22. At this time, the hollow portions 22a of the hollow fiber membranes 22 in the second end degassing element 2β and the first end degassing element 2α are in a decompressed state, so gas G, such as dissolved gas in the liquid L and bubbles contained in the liquid L, permeates the hollow fiber membranes 22. This degasses the liquid L. The degassed liquid L passes through the space between the second end degassing element 2β and the first end degassing element 2α and the housing 3A, and is discharged from the liquid discharge port 3b. The gas G that permeates the hollow fiber membranes 22 of the second end degassing element 2β and the first end degassing element 2α passes through the hollow portions 22a of the hollow fiber membranes 22 of the second end degassing element 2β and the first end degassing element 2α, the intermediate communicating space S4, the first end communicating space S1, the hollow portions 23a of the suction pipes 23 of the second end degassing element 2β and the first end degassing element 2α, and the second end communicating space S3, and is discharged from the suction port 3c and the first end suction port 3d.

[0128] As described above, in the degassing module 1B according to this embodiment, the housing 3B has a first-end suction port 3d connected to the first-end communication space forming portion 5B and communicating with the first-end communication space S1. Therefore, when suction is applied to the internal region R1 through the suction port 3c and the first-end suction port 3d, this suction force is transmitted to the intermediate communication space S4 and the first-end communication space S1 through the hollow portions 23a of the suction pipes 23 of the second-end degassing element 2β and the first-end degassing element 2α. This allows suction to be applied to the hollow portions 22a of the hollow fiber membranes 22 of the first-end degassing element 2α and the second-end degassing element 2β from both the second element end 2b side of the second-end degassing element 2β and the first element end 2a side of the first-end degassing element 2α. Furthermore, by suctioning the internal region R1 through both the suction port 3c and the first-end suction port 3d, the length of the discharge path for the gas G that has permeated the hollow fiber membranes 22 can be shortened, resulting in even higher degassing efficiency.

[0129] [Degassing module according to the fourth embodiment] Next, a degassing module according to a fourth embodiment will be described. The degassing module according to the fourth embodiment is basically the same as the degassing module 1A according to the second embodiment, but differs from the degassing module 1A according to the second embodiment in that the suction port is connected to the element connection part. Therefore, in the following description, only the differences from the degassing module 1A according to the second embodiment will be described, and the same description as the degassing module 1A according to the second embodiment will be omitted.

[0130] Fig. 15 is a schematic cross-sectional view of a degassing module according to a fourth embodiment. Fig. 16 is a schematic cross-sectional view of the degassing module shown in Fig. 15. As shown in Figs. 15 and 16, a degassing module 1C according to this embodiment includes multiple degassing elements 2, a housing 3C, an end baffle 4, a first end communication space forming portion 5, a partition portion 6, and an element connecting portion 7C. Note that Fig. 15 shows only the housing 3C in cross section.

[0131] Similar to the element connection part 7A of the second embodiment, the element connection part 7C forms an intermediate communication space S4 that communicates with the hollow portions 22a of the hollow fiber membranes 22 and the hollow portions 23a of the suction pipes 23 of the first end degassing element 2α and the hollow portions 22a of the hollow fiber membranes 22 and the hollow portions 23a of the suction pipes 23 of the second end degassing element 2β. The element connection part 7C also forms an intermediate liquid flow passage S5 that communicates with the hollow portions 21a of the liquid flow pipe 21 of the first end degassing element 2α and the hollow portions 21a of the liquid flow pipe 21 of the second end degassing element 2β. The element connection part 7C is larger than the element connection part 7A of the second embodiment so that the intermediate communication space S4 and the intermediate liquid flow passage S5 are larger than those of the second embodiment.

[0132] Like the element connection part 7C of the second embodiment, the element connection part 7C has a connecting cover 71A that is connected to the second fixing part 25 of the first end degassing element 2α and the first fixing part 24 of the second end degassing element 2β and covers the space between the first end degassing element 2α and the second end degassing element 2β, and a connecting pipe 72A that is connected to the liquid flow pipe 21 of the first end degassing element 2α and the liquid flow pipe 21 of the second end degassing element 2β.

[0133] The housing 3C accommodates the first end degassing element 2α and the second end degassing element 2β so that a space is formed between the first end degassing element 2α and the second end degassing element 2β. The housing 3C includes a cylindrical portion 31C that accommodates the first end degassing element 2α and the second end degassing element 2β and has an intermediate suction port 3e, a first lid portion 32 that is connected to one end of the cylindrical portion 31C and has a liquid discharge port 3b, and a second lid portion 33C that is connected to the end of the cylindrical portion 31C opposite to the first lid portion 32 and has a liquid supply port 3a.

[0134] The intermediate suction port 3e is provided in the cylindrical portion 31C and is a port that communicates between the inside and outside of the housing 3C. The intermediate suction port 3e extends in a pipe-like shape from the cylindrical portion 31C to the inside of the housing 3C and is connected to the connecting cover 71A of the element connecting portion 7C. The intermediate suction port 3e is communicated with the intermediate communication space S4 formed by the element connecting portion 7C. The intermediate suction port 3e may be configured integrally with the housing 3C or may be a separate member from the housing 3C.

[0135] [Method for degassing liquid according to the fourth embodiment]

[0136] Next, a liquid degassing method according to a fourth embodiment will be described. The liquid degassing method according to the fourth embodiment is a method for degassing a liquid L using a degassing module 1C.

[0137] In this degassing method, the intermediate suction port 3e of the degassing module 1C is suctioned, and the liquid L is supplied to the liquid supply port 3a of the degassing module 1C.

[0138] When the intermediate suction port 3e is suctioned, the internal region R1 connected to the intermediate suction port 3e is suctioned, and the internal region R1 is decompressed. Furthermore, when liquid L is supplied to the liquid supply port 3a, the liquid L is supplied to the external region R2 connected to the liquid supply port 3a. The liquid L supplied to the liquid supply port 3a is supplied to the hollow portions 21a of the liquid circulation pipes 21 of the second-end degassing element 2β and the first-end degassing element 2α. In the second-end degassing element 2β and the first-end degassing element 2α, the liquid L supplied to the hollow portions 21a of the liquid circulation pipes 21 is then discharged from the plurality of openings 21d of the liquid circulation pipes 21 to the outside of the liquid circulation pipes 21 and comes into contact with the plurality of hollow fiber membranes 22. At this time, in the second end degassing element 2β and the first end degassing element 2α, the hollow portions 22a of the plurality of hollow fiber membranes 22 are in a decompressed state, so that gas G, such as dissolved gas in the liquid L and air bubbles contained in the liquid L, permeates the plurality of hollow fiber membranes 22. This degasses the liquid L. The degassed liquid L passes through the space between the second end degassing element 2β and the first end degassing element 2α and the housing 3A, and is discharged from the liquid discharge port 3b. The gas G that permeates the plurality of hollow fiber membranes 22 of the second end degassing element 2β and the first end degassing element 2α passes through the hollow portions 22a of the plurality of hollow fiber membranes 22 of the second end degassing element 2β and the first end degassing element 2α, the intermediate communicating space S4, the first end communicating space S1, the hollow portions 23a of the plurality of suction pipes 23 of the second end degassing element 2β and the first end degassing element 2α, and the second end communicating space S3, and is discharged from the intermediate suction port 3e.

[0139] As described above, in the degassing module 1C according to this embodiment, the housing 3C includes an intermediate suction port 3e connected to the element connection portion 7C and communicating with the intermediate communication space S4. Therefore, when suction is applied to the internal region R1 through the intermediate suction port 3e, the suction force is transmitted from the intermediate communication space S4 to the first end communication space S1 and the second end communication space S3 through the hollow portions 23a of the suction pipes 23 of the second end degassing element 2β and the first end degassing element 2α. This allows suction to be applied to the hollow portions 22a of the hollow fiber membranes 22 of the first end degassing element 2α and the second end degassing element 2β from both the second element end 2b side of the second end degassing element 2β and the first element end 2a side of the first end degassing element 2α. Furthermore, because the intermediate suction port 3e is connected to the element connection portion 7C and communicates with the intermediate communication space S4, the length of the discharge path for the gas G that has permeated the hollow fiber membranes 22 can be shortened. This results in high degassing efficiency.

[0140] [Degassing module according to the fifth embodiment] Next, a degassing module according to a fifth embodiment will be described. The degassing module according to the fifth embodiment is basically the same as the degassing module 1A according to the second embodiment, but differs from the degassing module 1A according to the second embodiment in that it is equipped with three degassing elements. Therefore, in the following description, only the differences from the degassing module 1A according to the second embodiment will be described, and descriptions similar to those of the degassing module 1A according to the second embodiment will be omitted.

[0141] Fig. 17 is a schematic cross-sectional view of a degassing module according to a fourth embodiment. As shown in Fig. 17, a degassing module 1D according to this embodiment includes three degassing elements 2, a housing 3D, an end baffle 4 (see Fig. 12), a first-end communication space forming portion 5, a partition portion 6, and two element connection portions 7A. Note that Fig. 17 shows only the housing 3D in cross section.

[0142] The three degassing elements 2 are arranged in the extension direction D and are adjacent to each other in the extension direction D. The three degassing elements 2 are composed of a first end degassing element 2α located at an end in the first extension direction D1, a second end degassing element 2β located at an end in the second extension direction D2, and an intermediate degassing element 2γ located between the first end degassing element 2α and the second end degassing element 2β. Therefore, between the first end degassing element 2α and the intermediate degassing element 2γ that are adjacent to each other in the extension direction D, the first end degassing element 2α is the first side degassing element located on the first extension direction D1 side, and the intermediate degassing element 2γ is the second side degassing element located on the second extension direction D2 side. Furthermore, between the intermediate degassing element 2γ and the second end degassing element 2β, which are adjacent in the extension direction D, the intermediate degassing element 2γ is the first side degassing element located on the first extension direction D1 side, and the second end degassing element 2β is the second side degassing element located on the second extension direction D2 side.

[0143] The two element connection portions 7A are composed of a first element connection portion 7Aα that connects the first end degassing element 2α and the intermediate degassing element 2γ, and a second element connection portion 7Aβ that connects the intermediate degassing element 2γ and the second end degassing element 2β.

[0144] The first element connection portion 7Aα forms an intermediate communication space S4 that is a space that communicates with the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 of the first end degassing element 2α and the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 of the intermediate degassing element 2γ. The first element connection portion 7Aα also forms an intermediate liquid flow passage S5 that is a liquid flow passage that communicates with the hollow portions 21a of the liquid flow pipes 21 of the first end degassing element 2α and the hollow portions 21a of the liquid flow pipes 21 of the intermediate degassing element 2γ.

[0145] The second element connection part 7Aβ forms an intermediate communication space S4 that is a space that communicates with the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 of the intermediate degassing element 2γ and the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 of the second end degassing element 2β. The second element connection part 7Aβ also forms an intermediate liquid flow passage S5 that is a liquid flow passage that communicates with the hollow portions 21a of the liquid flow pipes 21 of the intermediate degassing element 2γ and the hollow portions 21a of the liquid flow pipes 21 of the second end degassing element 2β.

[0146] The housing 3D accommodates the first end degassing element 2α, the intermediate degassing element 2γ, and the second end degassing element 2β so that spaces are formed among the first end degassing element 2α, the intermediate degassing element 2γ, and the second end degassing element 2β. The housing 3D is equipped with a cylindrical portion 31D that accommodates the first end degassing element 2α, the intermediate degassing element 2γ, and the second end degassing element 2β and has an intermediate suction port 3e, a first cover portion 32 that is connected to one end of the cylindrical portion 31D and has a liquid discharge port 3b, and a second cover portion 33 that is connected to the end of the cylindrical portion 31D opposite to the first cover portion 32 and has a liquid supply port 3a and a suction port 3c.

[0147] The intermediate suction port 3e is provided in the cylindrical portion 31D and is a port that communicates between the inside and outside of the housing 3D. The intermediate suction port 3e extends in a pipe-like shape from the cylindrical portion 31D to the inside of the housing 3D and is connected to the connecting cover 71A (see FIG. 12) of the first element connecting portion 7Aα. The intermediate suction port 3e is communicated with the intermediate communication space S4 formed by the first element connecting portion 7Aα. The intermediate suction port 3e may be configured integrally with the housing 3D or may be a separate member from the housing 3D.

[0148] The end baffle 4 closes the end of the hollow portion 22a of the liquid circulation pipe 21 of the first end degassing element 2α on the first extending direction D1 side. The end baffle 4 is attached only to the first end degassing element 2α and does not close the hollow portion 22a of the liquid circulation pipe 21 of the intermediate degassing element 2γ or the second end degassing element 2β.

[0149] In addition, no components other than the end baffle 4 are provided in the hollow portion 21a and each intermediate communication space S4 of the liquid flow pipe 21 of the first end degassing element 2α, the intermediate degassing element 2γ, and the second end degassing element 2β to prevent the movement of the liquid L in the extension direction D.

[0150] The first end communicating space forming portion 5 is connected to the first fixing portion 24 of the first end degassing element 2α so as to cover the first element end portion 2a of the first end degassing element 2α. The first end communicating space forming portion 5 forms a first end communicating space S1, which is a space that communicates between the hollow portions 22a of the plurality of hollow fiber membranes 22 of the first end degassing element 2α and the hollow portions 23a of the plurality of suction pipes 23 of the first end degassing element 2α.

[0151] The partition portion 6 seals the gap between the second fixing portion 25 of the second end degassing element 2β and the housing 3D, thereby dividing the area within the housing 3D into an inner area R1 and an outer area R2.

[0152] [Method for degassing a liquid according to a fifth embodiment] Next, a liquid degassing method according to the fifth embodiment will be described. The liquid degassing method according to the fifth embodiment is a method for degassing a liquid L using a degassing module 1D.

[0153] In this degassing method, the suction port 3c and the intermediate suction port 3e of the degassing module 1D are suctioned, and the liquid L is supplied to the liquid supply port 3a of the degassing module 1A.

[0154] When the suction port 3c and the intermediate suction port 3e are suctioned, the internal region R1 connected to the suction port 3c and the intermediate suction port 3e is suctioned, and the internal region R1 is decompressed. Furthermore, when liquid L is supplied to the liquid supply port 3a, the liquid L is supplied to the external region R2 connected to the liquid supply port 3a. The liquid L supplied to the liquid supply port 3a is supplied to the hollow portions 21a of the liquid circulation pipes 21 of the second-end degassing element 2β, the intermediate degassing element 2γ, and the first-end degassing element 2α. Then, in the second-end degassing element 2β, the intermediate degassing element 2γ, and the first-end degassing element 2α, the liquid L supplied to the hollow portions 21a of the liquid circulation pipes 21 is discharged from the multiple openings 21d of the liquid circulation pipes 21 to the outside of the liquid circulation pipes 21 and comes into contact with the multiple hollow fiber membranes 22. At this time, in the second end degassing element 2β, the intermediate degassing element 2γ, and the first end degassing element 2α, the hollow portions 22a of the plurality of hollow fiber membranes 22 are in a decompressed state, so that gas G, such as dissolved gas in the liquid L and air bubbles contained in the liquid L, permeates the plurality of hollow fiber membranes 22. This degasses the liquid L. The degassed liquid L passes through the second end degassing element 2β, the intermediate degassing element 2γ, and the space between the first end degassing element 2α and the housing 3D, and is discharged from the liquid discharge port 3b. The gas G that has permeated the multiple hollow fiber membranes 22 of the second end degassing element 2β, the intermediate degassing element 2γ, and the first end degassing element 2α passes through the hollow portions 22a of the multiple hollow fiber membranes 22 of the second end degassing element 2β, the intermediate degassing element 2γ, and the first end degassing element 2α, the intermediate communicating space S4 formed by the second element connecting portion 7Aβ, the intermediate communicating space S4 formed by the first element connecting portion 7Aα, the first end communicating space S1, the hollow portions 23a of the multiple suction pipes 23 of the second end degassing element 2β, the intermediate degassing element 2γ, and the first end degassing element 2α, and the second end communicating space S3, and is discharged from the suction port 3c and the intermediate suction port 3e.

[0155] As described above, in the degassing module 1D according to this embodiment, the housing 3D has an intermediate suction port 3e connected to the first element connection portion 7Aα and communicating with the intermediate communication space S4. Therefore, when suction is applied to the internal region R1 through the suction port 3c and the intermediate suction port 3e, the suction force is transmitted through the hollow portions 23a of the suction pipes 23 of the second end degassing element 2β, the intermediate degassing element 2γ, and the first end degassing element 2α to the intermediate communication space S4 formed by the first element connection portion 7Aα, the intermediate communication space S4 formed by the second element connection portion 7Aβ, and the first end communication space S1. This causes suction into the hollow portions 22a of the hollow fiber membranes 22 of the first end degassing element 2α, the intermediate degassing element 2γ, and the second end degassing element 2β from both the second element end portion 2b side of the second end degassing element 2β and the first element end portion 2a side of the first end degassing element 2α. This makes it possible to obtain high degassing efficiency, thereby reducing the number of members connected to the degassing element 2 and the housing 3D for suctioning the hollow portions 22a of the plurality of hollow fiber membranes 22. Furthermore, by suctioning the internal region R1 from both the suction port 3c and the intermediate suction port 3e, the length of the discharge path for the gas G that has permeated the plurality of hollow fiber membranes 22 can be shortened, thereby obtaining even higher degassing efficiency.

[0156] [Degassing element according to the second embodiment] Next, a degassing element according to a second embodiment will be described. The degassing element according to the second embodiment is basically the same as the degassing element 2 according to the first embodiment, but differs from the degassing element 2 according to the first embodiment in that it further comprises an intermediate baffle. Therefore, in the following description, only the differences from the degassing element 2 according to the first embodiment will be described, and descriptions similar to those of the degassing element 2 according to the first embodiment will be omitted.

[0157] Fig. 18 is a schematic front view of a degassing element according to a second embodiment. Fig. 19 is a schematic cross-sectional view taken along line XIX-XIX in Fig. 18. Fig. 20 is a schematic cross-sectional view showing a portion of the degassing element shown in Fig. 18. As shown in Figs. 18 to 20, a degassing element 2E according to this embodiment includes a liquid distribution pipe 21, a plurality of hollow fiber membranes 22, a plurality of suction pipes 23, a first fixing part 24, a second fixing part 25, and an intermediate baffle 26.

[0158] The intermediate baffle 26 closes the hollow portion 22a of the liquid circulation pipe 21 at an element intermediate portion 2c between the first element end 2a and the second element end 2b. The element intermediate portion 2c is, for example, a portion located centrally between the first element end 2a and the second element end 2b. The intermediate baffle 26 is fitted into the hollow portion 21a of the liquid circulation pipe 21 at the element intermediate portion 2c. The intermediate baffle 26 prevents the liquid L from flowing between the first element end 2a and the second element end 2b of the liquid circulation pipe 21. Therefore, the liquid L supplied to the hollow portion 21a of the liquid circulation pipe 21 from either the first element end 2a or the second element end 2b must exit the liquid circulation pipe 21 through the multiple openings 21d and return to the hollow portion 21a of the liquid circulation pipe 21 through the multiple openings 21d.

[0159] As described above, in the degassing element 2E according to this embodiment, the hollow portion 21a of the liquid circulation pipe 21 is blocked by the intermediate baffle 26 in the element intermediate portion 2c between the first element end 2a and the second element end 2b. Therefore, the liquid L supplied to the hollow portion 21a of the liquid circulation pipe 21 can be discharged to the outside of the liquid circulation pipe 21 through the plurality of openings 21d on the upstream side of the intermediate baffle 26, brought into contact with the plurality of hollow fiber membranes 22, and then returned to the liquid circulation pipe 21 through the plurality of openings 21d on the downstream side of the intermediate baffle 26. This allows the liquid L to be in contact with the plurality of hollow fiber membranes 22 for a longer period of time.

[0160] [Degassing module according to the sixth embodiment] Fig. 21 is a schematic cross-sectional view of a degassing module according to a sixth embodiment. Fig. 22 is a schematic cross-sectional view of the degassing element shown in Fig. 21. Fig. 23 is a schematic cross-sectional view showing a portion of the degassing element shown in Fig. 21. Fig. 24 is a schematic cross-sectional view showing a portion of the degassing element shown in Fig. 21. Fig. 25 is a schematic cross-sectional view showing a portion of the degassing element shown in Fig. 21. As shown in Figs. 21 to 25, a degassing module 1E according to this embodiment includes the degassing element 2E according to the second embodiment described above, a housing 3E, a first-end communicating space forming portion 5E, and a partition portion 6E. Note that Fig. 21 shows only the housing 3E in cross section.

[0161] The housing 3E accommodates the degassing element 2E so that a space is formed between the degassing element 2E and the housing 3E. This space is a space between the degassing element 2E and the housing 3E through which the liquid L can flow.

[0162] The housing 3E includes a cylindrical portion 31 in which the degassing element 2E is accommodated, a first lid portion 32E connected to one end of the cylindrical portion 31 and having a liquid discharge port 3f, and a second lid portion 33 connected to the end of the cylindrical portion 31 opposite to the first lid portion 32E and having a liquid supply port 3a and a suction port 3c. The first lid portion 32E is connected to the end of the cylindrical portion 31 on the first extension direction D1 side so as to cover the opening of the cylindrical portion 31 on the first extension direction D1 side. The second lid portion 33 is connected to the end of the cylindrical portion 31 on the second extension direction D2 side so as to cover the opening of the cylindrical portion 31 on the second extension direction D2 side.

[0163] The liquid discharge port 3f is provided in the first cover portion 32E and is a port that communicates between the inside and outside of the housing 3E. The liquid discharge port 3f extends in a pipe shape from the first cover portion 32E to the inside of the housing 3E and is connected to the end 21f of the liquid circulation pipe 21 on the side in the first extension direction D1. The liquid discharge port 3f is in communication with the hollow portion 21a of the liquid circulation pipe 21.

[0164] The first end communicating space forming portion 5E, like the first end communicating space forming portion 5 of the first embodiment, is connected to the first element end portion 2a and forms a first end communicating space S1 that communicates between the hollow portions 22a of the multiple hollow fiber membranes 22 and the hollow portions 23a of the multiple suction pipes 23.

[0165] The partition 6E divides the area within the housing 3E into an inner area R1 and an outer area R2, with the plurality of hollow fiber membranes 22 as the boundary. The partition 6E has a first sealing portion 6Ea that seals the gap between the first fixing portion 24 of the degassing element 2E and the housing 3E, and a second sealing portion 6Eb that seals the gap between the second fixing portion 25 of the degassing element 2E and the housing 3E. Therefore, a second end communication space S3 that communicates with the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 is formed on the side of the degassing element 2E in the second extension direction D2.

[0166] [Method for degassing a liquid according to the sixth embodiment] Next, a description will be given of a liquid degassing method according to the sixth embodiment. The liquid degassing method according to the sixth embodiment is a method for degassing a liquid L using a degassing module 1E.

[0167] In this degassing method, the suction port 3c of the degassing module 1E is suctioned, and the liquid L is supplied to the liquid supply port 3a of the degassing module 1E.

[0168] When suction is applied to the suction port 3c, the internal region R1 connected to the suction port 3c is suctioned, and the internal region R1 is decompressed. Furthermore, by supplying the liquid L to the liquid supply port 3a, the liquid L is supplied to the external region R2 connected to the liquid supply port 3a. The liquid L supplied to the liquid supply port 3a is supplied from the second element end 2b to the hollow portion 21a of the liquid distribution pipe 21. The liquid L then bypasses the intermediate baffle 26 and is discharged from the multiple openings 21d on the upstream side of the intermediate baffle 26 into the space S2 outside the liquid distribution pipe 21. After contacting the multiple hollow fiber membranes 22, the liquid L returns to the hollow portion 21a of the liquid distribution pipe 21 through the multiple openings 21d on the downstream side of the intermediate baffle 26. The upstream side of the intermediate baffle 26 refers to the second element end 2b side of the intermediate baffle 26 or the side thereof in the second extending direction D2, and the downstream side of the intermediate baffle 26 refers to the first element end 2a side of the intermediate baffle 26 or the side thereof in the first extending direction D1. At this time, the hollow portions 22a of the plurality of hollow fiber membranes 22 are in a depressurized state, so gas G, such as dissolved gas in the liquid L and air bubbles contained in the liquid L, permeates the plurality of hollow fiber membranes 22. This degasses the liquid L. The degassed liquid L returned to the hollow portion 21a of the liquid circulation pipe 21 passes through the hollow portion 21a of the liquid circulation pipe 21 and is discharged from the liquid discharge port 3f. The gas G that permeates the plurality of hollow fiber membranes 22 passes through the hollow portions 22a of the plurality of hollow fiber membranes 22, the first end communicating space S1, the hollow portions 23a of the plurality of suction pipes 23, and the second end communicating space S3, and is discharged from the suction port 3c.

[0169] As described above, in the degassing module 1E according to this embodiment, the hollow portion 21a of the liquid circulation pipe 21 is blocked by the intermediate baffle 26 in the element intermediate portion 2c between the first element end 2a and the second element end 2b. Therefore, the flow of the liquid L supplied from the liquid supply port 3a to the hollow portion 21a of the liquid circulation pipe 21 in the extension direction D is prevented by the intermediate baffle 26. Therefore, the liquid L exits the liquid circulation pipe 21 from the multiple openings 21d on the upstream side of the intermediate baffle 26, comes into contact with the multiple hollow fiber membranes 22, and is degassed, and then returns to the hollow portion 21a of the liquid circulation pipe 21 on the downstream side of the intermediate baffle 26. This allows the liquid L to be in contact with the multiple hollow fiber membranes 22 for a longer period of time.

[0170] Furthermore, in this degassing module 1E, the partition portion 6E has a first sealing portion 6Ea that seals between the first fixing portion 24 and the housing 3E, and a second sealing portion 6Eb that seals between the second fixing portion 25 and the housing 3E, so that the internal region R1 and the external region F2 can be separated with a simple configuration.

[0171] Furthermore, in this degassing module 1E, the liquid discharge port 3f is connected to the end 21f of the liquid circulation pipe 21 in the first extension direction D1, so that the liquid that has come out of the liquid circulation pipe 21 from the multiple openings 21d can be returned to the hollow portion 21a of the liquid circulation pipe 21 from the multiple openings 21d, and then discharged from the liquid discharge port 3f.

[0172] [Degassing module according to the seventh embodiment] Next, a degassing module according to a seventh embodiment will be described. The degassing module according to the seventh embodiment is basically the same as the degassing module 1E according to the sixth embodiment, but differs from the degassing module 1E according to the sixth embodiment in that it includes a plurality of degassing elements 2E. Therefore, in the following description, only the differences from the degassing module 1E according to the sixth embodiment will be described, and descriptions similar to those of the degassing module 1E according to the sixth embodiment will be omitted.

[0173] Fig. 26 is a schematic cross-sectional view of a degassing module according to a seventh embodiment. Fig. 27 is a schematic cross-sectional view of the degassing module shown in Fig. 26. As shown in Figs. 26 and 27, a degassing module 1F according to this embodiment includes multiple degassing elements 2E, a housing 3F, a first-end communication space forming portion 5E, a partition portion 6F, and an element connecting portion 7A. Note that Fig. 26 shows a cross section of only the housing 3F.

[0174] The multiple degassing elements 2E are arranged in the extension direction D. The multiple degassing elements 2E are adjacent to each other in the extension direction D. In this embodiment, the multiple degassing elements 2E are composed of a first end degassing element 2Eα located at the end in the first extension direction D1 and a second end degassing element 2Eβ located at the end in the second extension direction D2. In other words, the degassing module 1F has two degassing elements. The first end degassing element 2Eα is also the first side degassing element located on the first extension direction D1 side of the two degassing elements 2E adjacent to each other in the extension direction D. Furthermore, the second end degassing element 2Eβ is also the second side degassing element located on the second extension direction D2 side of the two degassing elements 2E adjacent to each other in the extension direction D.

[0175] The housing 3F accommodates the first end degassing element 2Eα and the second end degassing element 2Eβ so that a space is formed between the first end degassing element 2Eα and the second end degassing element 2Eβ. The housing 3F includes a cylindrical portion 31F in which the first end degassing element 2Eα and the second end degassing element 2Eβ are accommodated, a first lid portion 32E connected to one end of the cylindrical portion 31F and having a liquid discharge port 3f, and a second lid portion 33 connected to the end of the cylindrical portion 31F opposite to the first lid portion 32E and having a liquid supply port 3a and a suction port 3c.

[0176] The element connection part 7A connects the first end degassing element 2Eα and the second end degassing element 2Eβ. The element connection part 7A forms an intermediate communication space S4 that communicates with the hollow portions 22a of the hollow fiber membranes 22 and the hollow portions 23a of the suction pipes 23 of the first end degassing element 2Eα and the hollow portions 22a of the hollow fiber membranes 22 and the hollow portions 23a of the suction pipes 23 of the second end degassing element 2Eβ. The element connection part 7A also forms an intermediate liquid flow passage S5 that communicates with the hollow portions 21a of the liquid flow pipes 21 of the first end degassing element 2Eα and the hollow portions 21a of the liquid flow pipes 21 of the second end degassing element 2Eβ.

[0177] The element connection part 7A is connected to the second fixing part 25 of the first-end degassing element 2Eα and the first fixing part 24 of the second-end degassing element 2Eβ and has a connecting cover 71A that covers the space between the first-end degassing element 2Eα and the second-end degassing element 2Eβ, and a connecting pipe 72A that is connected to the liquid circulation pipe 21 of the first-end degassing element 2Eα and the liquid circulation pipe 21 of the second-end degassing element 2Eβ. An intermediate liquid flow passage S5 is formed by the connecting pipe 72A, and the hollow part 21a of the liquid circulation pipe 21 of the first-end degassing element 2Eα communicates with the hollow part 21a of the liquid circulation pipe 21 of the second-end degassing element 2Eβ. In addition, an intermediate communication space S4 is formed by the connecting cover 71A and the connecting pipe 72A, which connects the hollow portions 22a of the multiple hollow fiber membranes 22 and the hollow portions 23a of the multiple suction pipes 23 of the first end degassing element 2Eα with the hollow portions 22a of the multiple hollow fiber membranes 22 and the hollow portions 23a of the multiple suction pipes 23 of the second end degassing element 2Eβ.

[0178] The liquid discharge port 3f is provided in the first cover portion 32E and is a port that communicates between the inside and outside of the housing 3F. The liquid discharge port 3f extends in a pipe shape from the first cover portion 32E to the inside of the housing 3F and is connected to the end 21f of the liquid circulation pipe 21 of the first-end degassing element 2Eα on the first extending direction D1 side. The liquid discharge port 3f is also communicated with the hollow portion 21a of the liquid circulation pipe 21 of the first-end degassing element 2Eα.

[0179] The first end communicating space forming portion 5E is connected to the first fixing portion 24 of the first end degassing element 2Eα so as to cover the first element end portion 2a of the first end degassing element 2Eα. The first end communicating space forming portion 5E forms a first end communicating space S1, which is a space that communicates between the hollow portions 22a of the plurality of hollow fiber membranes 22 of the first end degassing element 2Eα and the hollow portions 23a of the plurality of suction pipes 23 of the first end degassing element 2Eα.

[0180] The partition 6F divides the area within the housing 3F into an inner region R1 and an outer region R2, with the plurality of hollow fiber membranes 22 as a boundary. The partition 6F has a first sealing portion 6Fa that seals between the first fixing portion 24 of the first end degassing element 2Eα and the housing 3F, a second sealing portion 6Fb that seals between the second fixing portion 25 of the first end degassing element 2Eα and the housing 3F, a third sealing portion 6Fc that seals between the first fixing portion 24 of the second end degassing element 2Eβ and the housing 3F, and a fourth sealing portion 6Fd that seals between the second fixing portion 25 of the second end degassing element 2Eβ and the housing 3F. Therefore, a second end communicating space S3 that communicates with the hollow portions 22a of the plurality of hollow fiber membranes 22 and the hollow portions 23a of the plurality of suction pipes 23 is formed on the second extension direction D2 side of the second end degassing element 2Eβ. In addition, the space S2 outside the liquid flow pipe 21 is divided into two spaces: a first outer space S2α located between the first sealing portion 6Fa and the second sealing portion 6Fb, and a second outer space S2β located between the third sealing portion 6Fc and the fourth sealing portion 6Fd.

[0181] [Method for degassing a liquid according to the seventh embodiment] Next, a description will be given of a liquid degassing method according to the seventh embodiment. The liquid degassing method according to the seventh embodiment is a method for degassing a liquid L using a degassing module 1F.

[0182] In this degassing method, the suction port 3c of the degassing module 1F is suctioned, and the liquid L is supplied to the liquid supply port 3a of the degassing module 1F.

[0183] When suction is applied to the suction port 3c, the internal region R1 connected to the suction port 3c is suctioned, and the internal region R1 is decompressed. Furthermore, by supplying liquid L to the liquid supply port 3a, the liquid L is supplied to the external region R2 connected to the liquid supply port 3a. The liquid L supplied to the liquid supply port 3a is supplied to the hollow portion 21a of the liquid circulation pipe 21 of the second end degassing element 2β. The liquid L supplied to the hollow portion 21a of the liquid circulation pipe 21 of the second end degassing element 2β is discharged from the multiple openings 21d on the upstream side of the intermediate baffle 26 into the second outer space S2β outside the liquid circulation pipe 21, where it comes into contact with the multiple hollow fiber membranes 22. The upstream side of the intermediate baffle 26 refers to the second element end 2b side or the second extending direction D2 side. The liquid L then returns to the hollow portion 21a of the liquid circulation pipe 21 through the multiple openings 21d on the downstream side of the intermediate baffle 26 without flowing into the first outer space S2α, passes through the intermediate liquid flow passage S5, and is supplied to the hollow portion 21a of the liquid circulation pipe 21 of the first end degassing element 2α. The downstream side of the intermediate baffle 26 refers to the first element end 2a side or the first extending direction D1 side. The liquid L supplied to the hollow portion 21a of the liquid circulation pipe 21 of the first end degassing element 2α is discharged from the multiple openings 21d on the upstream side of the intermediate baffle 26 into the first outer space S2α outside the liquid circulation pipe 21, and comes into contact with the multiple hollow fiber membranes 22. The liquid L then returns to the hollow portion 21a of the liquid circulation pipe 21 through the multiple openings 21d on the downstream side of the intermediate baffle 26 without flowing into the second outer space S2β, and is discharged from the liquid discharge port 3f. At this time, the hollow portions 22a of the plurality of hollow fiber membranes 22 are in a decompressed state, so gas G, such as dissolved gas in the liquid L and air bubbles contained in the liquid L, permeates the plurality of hollow fiber membranes 22. This degasses the liquid L. The gas G that has permeated the plurality of hollow fiber membranes 22 passes through the hollow portions 22a of the plurality of hollow fiber membranes 22, the intermediate communicating space S4, the first end communicating space S1, the hollow portions 23a of the plurality of suction pipes 23, and the second end communicating space S3, and is discharged from the suction port 3c.

[0184] As described above, in the degassing module 1F according to this embodiment, the first end degassing element 2Eα and the second end degassing element 2Eβ each have an intermediate baffle 26 that blocks the hollow portion 21a of the liquid circulation pipe 21 in the element intermediate portion 2c between the first element end portion 2a and the second element end portion 2b. Therefore, in each of the first end degassing element 2Eα and the second end degassing element 2Eβ, the liquid L supplied to the liquid supply port 3a is prevented from flowing in the extension direction D by the intermediate baffle 26. Therefore, on the upstream side of the intermediate baffle 26, the liquid L exits the liquid circulation pipe 21 through the multiple openings 21d, comes into contact with the multiple hollow fiber membranes 22, and is degassed, and then returns to the hollow portion 21a of the liquid circulation pipe 21 on the downstream side of the intermediate baffle 26. This allows the liquid L to be in contact with the multiple hollow fiber membranes 22 for a longer period of time. In this degassing module 1F, the first end communicating space forming portion 5E is connected to the first element end portion 2a of the first end degassing element 2Eα, the first end communicating space S1 communicates with the hollow portions 22a of the multiple hollow fiber membranes 22 of the first end degassing element 2Eα and the hollow portions 23a of the multiple suction pipes 23 of the first end degassing element 2Eα, and a second end communicating space S3 is formed on the second extension direction D2 side of the second end degassing element 2Eβ, which is communicated with the hollow portions 22a of the multiple hollow fiber membranes 22 and the hollow portions 23a of the multiple suction pipes 23, and the suction port 3c is adjacent to the second end communicating space S3 and communicates with the second end communicating space S3. Therefore, the hollow portions 22a of the multiple hollow fiber membranes 22 of the first end degassing element 2Eα and the second end degassing element 2Eβ can be sucked from both the second element end 2b side of the second end degassing element 2Eβ and the first element end 2a side of the first end degassing element 2Eα.

[0185] In addition, in this degassing module 1F, the partition portion 6F has a first sealing portion 6Fa that seals between the first fixing portion 24 of the first end degassing element 2Eα and the housing 3F, a second sealing portion 6Fb that seals between the second fixing portion 25 of the first end degassing element 2Eα and the housing 3F, a third sealing portion 6Fc that seals between the first fixing portion 24 of the second end degassing element 2Eβ and the housing 3F, and a fourth sealing portion 6Fd that seals between the second fixing portion 25 of the second end degassing element 2Eβ and the housing 3F, so that the internal region R1 and the external region F2 can be separated with a simple configuration.

[0186] Furthermore, in this degassing module 1F, the liquid discharge port 3f is connected to the end 21f of the liquid circulation pipe 21 in the first extension direction D1 of the first end degassing element 2Eα, so that the liquid L that has come out of the liquid circulation pipe 21 from the multiple openings 21d can be returned to the hollow portion 21a of the liquid circulation pipe 21 from the multiple openings 21d, and then discharged from the liquid discharge port 3f.

[0187] Although the preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to the above embodiments.

[0188] For example, in the above embodiment, the degassing element has been described as having multiple suction pipes, but the degassing element may have only one suction pipe. In this case, the cross-sectional area of ​​the hollow portion 23a of the suction pipe 23 may be larger than the total cross-sectional area of ​​the hollow portions 22a of the multiple hollow fiber membranes 22. In this way, when the degassing element 2 has only one suction pipe 23, the cross-sectional area of ​​the hollow portion 23a of the suction pipe 23 is larger than the total cross-sectional area of ​​the hollow portions 22a of the multiple hollow fiber membranes 22, so that the pressure loss (suction loss) caused by suction in the hollow portion 23a of the suction pipe 23 can be made smaller than the pressure loss (suction loss) caused by suction in the hollow portions 22a of the multiple hollow fiber membranes 22. This makes it possible to achieve the same effect as when the degassing element has multiple suction pipes.

[0189] Furthermore, the number of degassing elements provided in the degassing module is not particularly limited. For example, the degassing module may include one degassing element as in the first embodiment, two degassing elements as in the second and third embodiments, or three degassing elements as in the fourth embodiment. Furthermore, the degassing module may include four or more degassing elements.

[0190] Furthermore, when the degassing module has multiple degassing elements, adjacent degassing elements in the extension direction D may be arranged spaced apart from each other as in the above embodiment, or may be arranged without space between each other if they can be directly connected.

[0191] Furthermore, in the above embodiment, the configuration of the housing has been specifically described, but the housing may have any configuration as long as it accommodates the degassing unit and has a liquid supply port, a liquid discharge port, and a suction port. For example, the liquid discharge port may be provided in the cylindrical portion. Also, for example, the cylindrical portion may be divided into multiple portions. Dividing the cylindrical portion into multiple portions is particularly effective when it is not easy to accommodate multiple degassing elements in the cylindrical portion. [Explanation of symbols]

[0192] 1... degassing module, 1A... degassing module, 1B... degassing module, 1C... degassing module, 1D... degassing module, 1E... degassing module, 1F... degassing module, 2... degassing element, 2a... first element end, 2b... second element end, 2c... element middle part, 2E... degassing element, 2Eα... first end degassing element, 2Eβ... second end degassing element, 2α... first end degassing element, 2β... second end degassing element, 2γ... intermediate degassing element, 3... housing, 3A... housing, 3B... housing, 3C... Housing, 3D...housing, 3E...housing, 3F...housing, 3a...liquid supply port, 3b...liquid discharge port, 3c...suction port, 3d...first end suction port, 3e...intermediate suction port, 3f...liquid discharge port, 4...end baffle, 5...first end communicating space forming portion, 5B...first end communicating space forming portion, 5E...first end communicating space forming portion, 6...partition portion, 6E...partition portion, 6Ea...first sealing portion, 6Eb...second sealing portion, 6F...partition portion, 6Fa...first sealing portion, 6Fb...second sealing portion, 6Fc...third sealing portion, 6Fd...fourth sealing portion, 7A...element connection connection portion, 7Aα...first element connection portion, 7Aβ...second element connection portion, 7C...element connection portion, 21...liquid circulation pipe, 21a...hollow portion, 21b...first end liquid circulation pipe opening, 21c...second end liquid circulation pipe opening, 21d...opening, 21e...end portion, 21f...end portion, 22...hollow fiber membrane, 22a...hollow portion, 22b...first end hollow fiber membrane opening, 22c...second end hollow fiber membrane opening, 23...suction pipe, 23a...hollow portion, 23b...first end suction pipe opening, 23c...second end suction pipe opening, 24...first fixing portion, 25...second fixing portion, 26...intermediate baffle 31... Cylindrical part, 31A... Cylindrical part, 31C... Cylindrical part, 31D... Cylindrical part, 31F... Cylindrical part, 32... First cover part, 32B... First cover part, 32E... First cover part, 33... Second cover part, 33C... Second cover part, 71A... Connection cover, 72A... Connection pipe, D... Extension direction, D1... First extension Direction, D2...second extension direction, F2...external region, G...gas, L...liquid, R1...internal region, R2...external region, S1...first end communication space, S2...space, S2α...first outer space, S2β...second outer space, S3...second end communication space, S4...intermediate communication space, S5...intermediate liquid flow path.

Claims

1. a liquid flow pipe having a plurality of openings formed therein and extending in an extension direction; a plurality of hollow fiber membranes arranged around the liquid distribution pipe so as to extend along the liquid distribution pipe and cover the plurality of openings; a suction pipe extending along the liquid flow pipe; a first fixing portion located at a first element end portion which is an end portion in a first extension direction which is one of the extension directions, and which fixes the plurality of hollow fiber membranes and the suction pipe to the liquid distribution pipe so as to seal between the liquid distribution pipe, the plurality of hollow fiber membranes, and the suction pipe and to open a hollow portion of the liquid distribution pipe, a hollow portion of the plurality of hollow fiber membranes, and a hollow portion of the suction pipe; a second fixing portion located at a second element end portion which is an end portion in a second extension direction which is opposite to the first extension direction in the extension direction, and which fixes the plurality of hollow fiber membranes and the suction pipe to the liquid distribution pipe so as to seal between the liquid distribution pipe, the plurality of hollow fiber membranes, and the suction pipe and to open the hollow portion of the liquid distribution pipe, the hollow portion of the plurality of hollow fiber membranes, and the hollow portion of the suction pipe, Degassing element.

2. The cross-sectional area of ​​the hollow portion of the suction pipe is larger than the total cross-sectional area of ​​the hollow portions of the plurality of hollow fiber membranes. The degassing element according to claim 1 .

3. The suction pipe is arranged outside the plurality of hollow fiber membranes. The degassing element according to claim 1 .

4. A plurality of the suction pipes are provided. The degassing element according to claim 1 .

5. The total cross-sectional area of ​​the hollow portions of the plurality of suction pipes is larger than the total cross-sectional area of ​​the hollow portions of the plurality of hollow fiber membranes. The degassing element according to claim 4.

6. The plurality of suction pipes are arranged around the plurality of hollow fiber membranes. The degassing element according to claim 4.

7. The plurality of suction pipes are arranged at equal intervals in the circumferential direction of the liquid circulation pipe. The degassing element according to claim 6.

8. an intermediate baffle that closes the hollow portion of the liquid distribution pipe in an element intermediate portion between the first element end and the second element end; The degassing element according to claim 1 .

9. A degassing element according to any one of claims 1 to 8; a housing that accommodates the degassing element; a first end communication space forming portion connected to the first element end; a partition section that divides the area within the housing into an internal area including the hollow portions of the hollow fiber membranes and the hollow portion of the suction pipe and an external area including the hollow portion of the liquid distribution pipe, with the hollow fiber membranes as a boundary, the first-end communicating space forming portion forms a first-end communicating space that communicates the hollow portions of the plurality of hollow fiber membranes with the hollow portion of the suction pipe, The housing includes: a liquid supply port for supplying liquid to the hollow portion of the liquid circulation pipe; a liquid discharge port for discharging the liquid discharged from the liquid distribution pipe; a suction port for suctioning the interior region; Degassing module.

10. the liquid supply port is connected to an end of the liquid circulation pipe in the second extension direction. The degassing module of claim 9.

11. an end baffle that closes a hollow portion of the liquid flow pipe at the first element end of the degassing element; The degassing module of claim 9.

12. The partition portion seals the second fixing portion and the housing. The degassing module of claim 11.

13. a second end communication space communicating with the hollow portions of the plurality of hollow fiber membranes and the hollow portion of the suction pipe is formed on the second extension direction side of the degassing element, the suction port is adjacent to the second end communication space and communicates with the second end communication space; The degassing module of claim 11.

14. the degassing element has an intermediate baffle that closes the hollow portion of the liquid distribution pipe in an element intermediate portion between the first element end and the second element end. The degassing module of claim 13.

15. The partition portion has a first sealing portion that seals the gap between the first fixing portion and the housing, and a second sealing portion that seals the gap between the second fixing portion and the housing.

15. The degassing module of claim 14.

16. the liquid discharge port is connected to an end of the liquid circulation pipe in the first extension direction.

15. The degassing module of claim 14.

17. A plurality of the degassing elements is provided, The plurality of degassing elements are arranged in the extension direction, Between the degassing elements adjacent to each other in the extension direction, the hollow portions of the plurality of hollow fiber membranes and the hollow portions of the suction pipes are in communication with each other, and the hollow portions of the liquid circulation pipes are in communication with each other. The degassing module of claim 9.

18. the liquid supply port is connected to an end of the liquid circulation pipe in the second extension direction of a second end degassing element that is located at an end in the second extension direction among the plurality of degassing elements.

18. The degassing module of claim 17.

19. an element connecting portion that disposes, apart from each other in the extension direction, a first side degassing element located on the first extension direction side of the degassing elements adjacent to each other in the extension direction, and a second side degassing element located on the second extension direction side of the degassing elements adjacent to each other in the extension direction; The element connection portion is an intermediate communication space communicating with the hollow portions of the hollow fiber membranes of the first degassing element and the hollow portion of the suction pipe, and with the hollow portions of the hollow fiber membranes of the second degassing element and the hollow portion of the suction pipe; forming an intermediate liquid flow passage that is in communication with the hollow portion of the liquid flow pipe of the first degassing element and the hollow portion of the liquid flow pipe of the second degassing element; 18. The degassing module of claim 17.

20. The element connection portion is a connecting cover connected to the second fixing portion of the first degassing element and the first fixing portion of the second degassing element, the connecting cover covering a space between the first degassing element and the second degassing element; a connecting pipe connected to the liquid circulation pipe of the first degassing element and the liquid circulation pipe of the second degassing element, 20. The degassing module of claim 19.

21. the suction port is connected to the element connection portion and communicates with the intermediate communication space; 20. The degassing module of claim 19.

22. an end baffle that closes the hollow portion of the liquid circulation pipe of a first end degassing element that is located at an end in the first extension direction among the plurality of degassing elements, the first end communication space forming portion is connected to the first element end portion of a first end degassing element that is located at an end in the first extension direction among the plurality of degassing elements, the first end communication space communicates the hollow portions of the hollow fiber membranes of the first end degassing element with the hollow portion of the suction pipe of the first end degassing element, a second end communication space communicating with the hollow portions of the hollow fiber membranes and the hollow portion of the suction pipe is formed on the second extension direction side of a second end degassing element located at an end in the second extension direction among the plurality of degassing elements, the suction port is adjacent to the second end communication space and communicates with the second end communication space; 18. The degassing module of claim 17.

23. the housing has a first-end suction port connected to the first-end communication space forming portion and communicating with the first-end communication space; 23. The degassing module of claim 22.

24. the partition portion seals the second fixing portion of the second end degassing element and the housing.

23. The degassing module of claim 22.

25. each of the plurality of degassing elements has an intermediate baffle that closes the hollow portion of the liquid distribution pipe in an element intermediate portion between the first element end and the second element end; the first end communication space forming portion is connected to the first element end portion of a first end degassing element that is located at an end in the first extension direction among the plurality of degassing elements, the first end communication space communicates the hollow portions of the hollow fiber membranes of the first end degassing element with the hollow portion of the suction pipe of the first end degassing element, a second end communication space communicating with the hollow portions of the hollow fiber membranes and the hollow portion of the suction pipe is formed on the second extension direction side of a second end degassing element located at an end in the second extension direction among the plurality of degassing elements, the suction port is adjacent to the second end communication space and communicates with the second end communication space; 18. The degassing module of claim 17.

26. The partition portion has a first sealing portion that seals between the housing and the first fixing portion of a first side degassing element that is located on the first extension direction side of the degassing elements adjacent to each other in the extension direction, a second sealing portion that seals between the housing and the second fixing portion of the first side degassing element, a third sealing portion that seals between the housing and the first fixing portion of a second side degassing element that is located on the second extension direction side of the degassing elements adjacent to each other in the extension direction, and a fourth sealing portion that seals between the housing and the second fixing portion of the second side degassing element.

26. The degassing module of claim 25.

27. the liquid discharge port is connected to an end of the liquid circulation pipe in the first extension direction of a first end degassing element that is located at an end in the first extension direction among the plurality of degassing elements.

26. The degassing module of claim 25.

28. The housing includes: a cylindrical portion in which the degassing element is housed; a first cover portion connected to one end of the cylindrical portion and having the liquid discharge port; a second cover portion connected to an end of the cylindrical portion opposite to the first cover portion and having the liquid supply port; At least one of the first lid portion and the second lid portion has the suction port. The degassing module of claim 9.

29. 10. A method for degassing a liquid using the degassing module of claim 9, comprising: applying suction to the suction port of the degassing module and supplying liquid to the liquid supply port of the degassing module; How to degas a liquid.

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