Plate-and-frame type separation membrane element and separation apparatus

Abstract

To provide a plate and frame type separation membrane element capable of preventing the lowering of selectivity with respect to a target fluid component even if a high temperature and high humidity fluid is supplied.SOLUTION: A plate-and-frame type separation membrane element is constituted by laminating a permeation side flow passage member 6, a separation membrane 4 having a separation functional layer, a feed side sealing part 3 having a peeling adhesive strength of ≥ 0.5N / 25 mm and a feed side flow passage member 2 in this order inside a vessel 7 having a linear expansion coefficient of ≤ 60.0 * 10 - 6 / °C.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a plate-and-frame type separation membrane element and a separation device. [Background technology]

[0002] Plate-and-frame separation membrane elements, which are made by stacking flat membranes, are known as separation membranes for separating specific fluid components from liquid or gaseous raw fluids (for example, Patent Documents 1 and 2). In recent years, the performance of separation membranes has improved, making it possible to realize thinner separation membranes. Such thin separation membranes can be used to remove carbon dioxide and other substances contained in gases such as exhaust gases. The plate-and-frame separation membrane elements can use thin separation membranes that are difficult to use with spiral-wound separation membrane elements. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-000964 [Patent Document 2] Special Publication No. 2016-500335 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when a high-temperature and high-humidity fluid such as exhaust gas is supplied to a plate-and-frame type separation membrane element such as those described in Patent Documents 1 and 2, leakage of the fluid may occur, resulting in a decrease in selectivity for the target fluid component.

[0005] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a plate-and-frame type separation membrane element that does not leak fluid even when a high-temperature and high-humidity fluid is supplied, and that can maintain good selectivity for target fluid components. [Means for solving the problem]

[0006] The inventors discovered that the above problem can be solved by a separation membrane element in which the peel adhesive strength of the sealing portion located between the supply side flow path member and the separation membrane under high temperature and high humidity conditions and the linear expansion coefficient of the container are within a specified range, and thus completed the present invention.

[0007] In order to solve the above problems, a plate-and-frame type separation membrane element according to one aspect of the present invention is a plate-and-frame type separation membrane element including a separation membrane having a separation functional layer, a feed-side channel member, and a permeate-side channel member in a container, the separation functional layer is a layer that selectively separates a specific fluid component contained in the raw material fluid, a sealing portion is disposed between the supply-side channel member and the separation membrane, The peel adhesive strength of the sealing part is 0.5 N / 25 mm or more, The linear expansion coefficient of the container is 60.0 × 10 -6 / ℃ or less. (Here, the peel adhesive strength is measured by a T-peel test conducted on a 100 mm × 25 mm test piece for measuring peel adhesive strength cut out from the sealed portion, under conditions of a temperature of 60°C and a humidity of 85% RH, in accordance with JIS K 6854-3; and the linear expansion coefficient is measured on a 7 mm wide × 10 mm long × 5 mm thick test piece for measuring linear expansion coefficient cut out from the side wall of the container, in accordance with JIS R 1618, under conditions of measurement direction: lengthwise, temperature range: room temperature to 150°C (however, if the softening point or melting point of the test piece for measuring linear expansion coefficient is 150°C or lower, measurement is conducted to the temperature just before that point), temperature increase / decrease rate: 5°C / min, load: approximately 0.05 N, and measurement atmosphere: He.) [Effects of the Invention]

[0008] According to one aspect of the present invention, a plate-and-frame separation membrane element can be provided that, even when a high-temperature and high-humidity fluid is supplied, does not leak the gas and can maintain good selectivity for the target fluid component. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram showing an example of a plate-and-frame type separation membrane element according to one embodiment of the present invention, illustrating a cross section of the separation membrane element cut in a direction parallel to the end where the permeate-side plugging portion is located. [Figure 2] FIG. 2 is a diagram showing a process for preparing a membrane stack part of a plate-and-frame type separation membrane element according to one embodiment of the present invention. [Figure 3] FIG. 1 is a view showing an embodiment of a plate-and-frame type separation membrane element container according to one embodiment of the present invention, which is a container not provided with an upper surface portion (upper lid). [Figure 4] FIG. 1 is a view showing a state in which permeate-side channel members and permeate-side plugs have been stacked in a container during the production of a plate-and-frame separation membrane element according to one embodiment of the present invention. [Figure 5] FIG. 5 is a diagram illustrating a state in which a film stack portion is further stacked from the state shown in FIG. 4. [Figure 6] FIG. 6 is a diagram illustrating a state in which a permeate-side channel member and a permeate-side plugging unit are further stacked on top of the state shown in FIG. 5. [Figure 7] FIG. 7 is a diagram illustrating a state in which a film stack portion is further stacked from the state shown in FIG. 6. [Figure 8] FIG. 1 is a diagram illustrating a state in which permeate-side channel members, permeate-side plugs, and membrane stacks are repeatedly stacked in a container. [Figure 9] FIG. 1 is a diagram illustrating the appearance of an example of a plate-and-frame type separation membrane element according to one embodiment of the present invention. [Figure 10] FIG. 1 is a schematic diagram showing the configuration of an apparatus for evaluating the performance of a separation membrane element used in Examples. DETAILED DESCRIPTION OF THE INVENTION

[0010] Although one embodiment of the present invention will be described below, the present invention is not limited to the following embodiments. Various modifications of the present invention are possible within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

[0011] [Embodiment 1: Plate-and-frame type separation membrane element] A plate-and-frame separation membrane element according to one embodiment of the present invention (hereinafter also referred to as "the present separation membrane element") is a plate-and-frame separation membrane element comprising, within a container, a separation membrane having a separation functional layer, a feed-side channel member, and a permeate-side channel member, wherein the separation functional layer is a layer that selectively separates a specific fluid component contained in a raw fluid, a seal is disposed between the feed-side channel member and the separation membrane, the peel adhesive strength of the seal is 0.5 N / 25 mm or more, and the linear expansion coefficient of the container is 60.0 × 10 -6 It is a plate-and-frame type separation membrane element with a temperature of 1000KJ / °C or less. (Here, the peel adhesive strength is measured by a T-peel test conducted on a 100 mm × 25 mm test piece for measuring peel adhesive strength cut out from the sealed portion, under conditions of a temperature of 60°C and a humidity of 85% RH, in accordance with JIS K 6854-3; and the linear expansion coefficient is measured on a 7 mm wide × 10 mm long × 5 mm thick test piece for measuring linear expansion coefficient cut out from the side wall of the container, in accordance with JIS R 1618, under conditions of measurement direction: length direction, temperature range: room temperature to 150°C (however, if the softening point or melting point of the test piece for measuring linear expansion coefficient is 150°C or lower, measurement is conducted to the temperature just before that point), temperature increase / decrease rate: 5°C / min, load: approximately 0.05 N, and measurement atmosphere: He.) Hereinafter, the plug disposed between the supply-side flow path member and the separation membrane will be referred to as the "supply-side plug." This separation membrane element may have, for example, the configuration shown in FIG. 1. This separation membrane element also has, for example, the appearance shown in FIG. 9. Hereinafter, the mechanism and configuration of this separation membrane element will be described with reference to FIGS. 1 and 9.

[0012] Fig. 1 shows an example of the separation membrane element, and is a schematic diagram showing a cross section of the separation membrane element cut in a direction parallel to the end where the permeate-side plugging section is located. Fig. 9 is a diagram showing the appearance of an example of a plate-and-frame type separation membrane element according to one embodiment of the present invention.

[0013] The separation membrane element 1 shown in Figure 1 includes a stack of a permeate-side flow path member 6, a permeate-side plugging section 5, a separation membrane 4, a feed-side plugging section 3, a feed-side flow path member 2, a feed-side plugging section 3, a separation membrane 4, a permeate-side plugging section 5, and a permeate-side flow path member 6, all stacked in a container 7. The container 7 is also composed of a bottom section 7a, a side wall section 7b, and an upper section (top cover) 7c. Hereinafter, the separation membrane element referred to as "separation membrane element 1" is this separation membrane element.

[0014] <Mechanism of the present invention> The mechanism of the present invention will be explained below by comparing the present separation membrane element with a conventional separation membrane element. The conventional separation membrane element is a separation membrane element that includes the laminate in a container and has a peel adhesive strength and a linear expansion coefficient outside the ranges of the present separation membrane element. Hereinafter, when simply referring to a "separation membrane element," it means both the present separation membrane element and the conventional separation membrane element.

[0015] A separation membrane element can separate a specific fluid component as follows: First, a raw material fluid is supplied to a supply-side flow path member of the separation membrane element. Here, the method for supplying the raw material fluid is not particularly limited. For example, if the separation membrane element has a first supply port (described below), the raw material fluid can be supplied from the first supply port to the second end (described below) side of the stack.

[0016] Next, the raw fluid is supplied from the feed-side channel member to the separation membrane, and at least a portion of the raw fluid passes through the separation membrane. Here, the separation functional layer included in the separation membrane is a layer that can selectively permeate specific fluid components contained in the raw fluid. Therefore, the permeated fluid that has permeated the separation membrane has a higher content of the specific fluid component than the raw fluid. Furthermore, because the separation membrane element is equipped with a feed-side plug, the raw fluid supplied to the feed-side channel member and the non-permeated fluid that has not permeated the separation membrane are prevented from mixing with the permeated fluid flowing through the permeate-side channel member. The non-permeated fluid that has not permeated the separation membrane flows through the feed-side channel member and is discharged to the outside of the separation membrane element.

[0017] The method for discharging the non-permeated fluid to the outside is not particularly limited. For example, if the separation membrane element has a first outlet (described later), the non-permeated fluid can be discharged to the outside through the first outlet. The permeated fluid that has permeated the separation membrane flows through the permeate-side channel member and is discharged to the outside of the separation membrane element.

[0018] The method for discharging the permeated fluid to the outside is not particularly limited. For example, if the separation membrane element has a second outlet (described later), the permeated fluid can be discharged to the outside through the second outlet. Furthermore, if the separation membrane element has a supply / discharge outlet (described later), the permeated fluid can also be discharged to the outside through the supply / discharge outlet. This allows the separation membrane element to separate the raw material fluid into a permeated fluid and a non-permeated fluid.

[0019] When a raw fluid is supplied to a separation membrane element, internal pressure is generated toward the separation membrane in the supply-side space formed by the supply-side channel member through which the raw fluid flows. Furthermore, in conventional separation membrane elements, when the raw fluid is a high-temperature, high-humidity fluid such as exhaust gas, the supply-side plugs come into contact with the high-temperature, high-humidity fluid and are placed in a high-temperature, high-humidity environment, resulting in a decrease in adhesive strength of the supply-side plugs. When this adhesive strength decreases, the internal pressure creates a gap between the supply-side channel member and the separation membrane that leads to the outside of the separation membrane element, and the raw fluid leaks through this gap. This causes the raw fluid that has not passed through the separation membrane to mix with the permeated fluid, reducing selectivity for the target fluid component.

[0020] On the other hand, the separation membrane element 1 has a peel adhesion strength of the feed-side plugs 3 of 0.5 N / 25 mm or more, which is higher than that of conventional separation membrane elements. Here, the peel adhesion strength is measured under high-temperature and high-humidity conditions of a temperature of 60°C and a humidity of 85% RH. In other words, the peel adhesion strength represents the adhesive strength of the feed-side plugs 3 under high-temperature and high-humidity conditions. Therefore, in the separation membrane element 1, the feed-side plugs 3 maintain high adhesive strength even when the raw fluid is at high temperature and humidity, thereby reducing the occurrence of gaps between the feed-side channel member 2 and the separation membrane 4. As a result, the occurrence of leaks is reduced, and good selectivity for the target fluid component can be maintained.

[0021] Here, the peel bond strength is measured by a T-peel test in accordance with JIS K 6854-3, which is carried out on a 100 mm × 25 mm test piece for measuring peel bond strength cut out from the supply-side sealing portion 3 under conditions of a temperature of 60°C and a humidity of 85% RH. The peel bond strength can be measured, for example, by a method described in the Examples. The peel bond strength may be measured using one test piece for measuring peel bond strength, or may be measured on two or more test pieces for measuring peel bond strength, and the average of the measured values ​​obtained may be used as the peel bond strength.

[0022] The higher the peel strength, the better, from the viewpoint of maintaining better selectivity for the target fluid component. The lower limit of the peel strength is preferably 0.6 N / 25 mm or more, and more preferably 0.7 N / 25 mm or more. The upper limit of the peel strength is not particularly limited, and may be, for example, 30 N / 25 mm or less, or 50 N / 25 mm or less.

[0023] In conventional separation membrane elements, when the raw fluid is a high-temperature, high-humidity fluid such as exhaust gas, the container also thermally expands and deforms due to contact with the fluid. In this case, a gap forms between the end of a stack formed by stacking a feed-side channel member, a separation membrane, a permeate-side channel member, etc. and the container, particularly the side wall of the container. This causes leakage of the raw fluid through the gap, reducing selectivity for the target fluid component.

[0024] On the other hand, the separation membrane element 1 has a linear expansion coefficient of 60.0×10 -6 / °C or less, the container 7 is less likely to thermally expand or deform. This reduces the occurrence of gaps between the end and the container 7, particularly the side wall portion 7b. As a result, the occurrence of leaks and selectivity for the target fluid component can be maintained well.

[0025] Here, the linear expansion coefficient is measured using a test piece for measuring the linear expansion coefficient, which is cut out from the side wall of the container and has a dimension of 7 mm in width, 10 mm in length, and 5 mm in thickness, in accordance with JIS R 1618, under the following conditions: <Condition> Measurement direction: lengthwise, Temperature range: Room temperature to 150°C (however, if the softening point or melting point is below 150°C, up to the temperature just before that point) Temperature increase / decrease rate: 5℃ / min, Load: about 0.05N, Measurement atmosphere: He.

[0026] The room temperature is 25° C. The linear expansion coefficient can be measured, for example, by the method described in the Examples. The linear expansion coefficient may be measured using one of the test pieces for measuring the linear expansion coefficient, or two or more of the test pieces for measuring the linear expansion coefficient may be measured, and the average value of the obtained measured values ​​may be used as the linear expansion coefficient.

[0027] The measurement of the linear expansion coefficient is preferably carried out by repeating a cycle of temperature increase and decrease a number of times, for example, three times. In this specification, the term "a load of about 0.05 N" specifically means that the load is within a range of 0.05±0.02 N, for example.

[0028] The linear expansion coefficient is preferably as low as possible in order to maintain the selectivity for the target fluid component. From this viewpoint, the upper limit of the linear expansion coefficient is set to 55.0×10 -6 / °C or less, and -6 / °C or less, and more preferably 30.0 × 10 -6 / °C or less, and more preferably 20.0 × 10 -6 The lower limit of the linear expansion coefficient is not particularly limited, and is, for example, 5.0 × 10 -6 / °C or more, and may be 0.9 x 10 -6 / ℃ or more.

[0029] <Configuration of this separation membrane element> The separation membrane element 1 includes a separation membrane 4 having a region in which it is arranged in a flat membrane state within a container 7. "Separation membrane 4 having a region in which it is arranged in a flat membrane state within a container 7" means that the separation membrane 4 is accommodated within the container 7 so as to include a region in which it is arranged in a flat state without being wound into a roll or a cylinder. Here, "inside the container 7" refers to the region surrounded by the bottom surface 7a, side wall portion 7b, and top surface (top lid) 7c. The separation membrane 4 accommodated within the container 7 may have a folded portion as long as it has a region in which it is arranged in a flat membrane state within the container 7, and as described below, it may be accommodated within the container 7 in a folded state so as to form a flat membrane region.

[0030] As shown in FIG. 1 , a separation membrane element 1 may have a configuration in which a container 7 houses a stack having two permeate-side channel members 6 and a separation membrane 4 and a feed-side channel member 2 disposed between the two permeate-side channel members 6. The height direction of the container 7 coincides with the stacking direction of the stack. The separation membranes 4 are stacked so as to have a region in which they are arranged in a flat membrane shape within the container 7. The permeate-side channel member 6 and the feed-side channel member 2 are also usually stacked so as to have a region in which they are arranged in a flat membrane shape within the container 7.

[0031] The laminate may have at least a configuration in which a permeate-side channel member 6, a separation membrane 4 having a separation functional layer, and a feed-side channel member 2 are stacked, with a feed-side plugging portion 3 disposed between the supply-side channel member 2 and the separation membrane 4. The laminate may also have a membrane stack portion in which a separation membrane 4, a feed-side plugging portion 3, a supply-side channel member 2, a feed-side plugging portion 3, and a separation membrane 4 are stacked in this order, as shown in FIG. 1 . The laminate preferably has a structure in which a membrane stack portion is disposed between two permeate-side channel members 6. As shown in FIG. 1 , the laminate may also have a plugging portion 5 disposed between the permeate-side channel member 6 and the separation membrane 4, and the plugging portion 5 may bond the permeate-side channel member 6 and the separation membrane 4. Hereinafter, the plugging portion 5 disposed between the permeate-side channel member 6 and the separation membrane 4 will be referred to as the "permeate-side plugging portion."

[0032] The separation membrane element 1 preferably includes the permeate-side plugging section 5. The reason for this is that the permeated fluid that permeates the separation membrane 4 and flows through the permeate-side channel member 6 can be prevented from mixing with the raw fluid and non-permeated fluid flowing through the feed-side channel member 2.

[0033] In the laminate, the membrane laminate and the permeate-side channel member 6 laminated on the membrane laminate may constitute a membrane leaf. The membrane leaf is a laminate having a layer structure in which a permeate-side channel member 6, a separation membrane 4, a feed-side channel member 2, and a separation membrane 4 are laminated in this order. Here, in the membrane leaf, a feed-side plugging member 3 is disposed between the separation membrane 4 and the feed-side channel member 2, and optionally, a permeate-side plugging member 5 is installed between the separation membrane 4 and the permeate-side channel member 6.

[0034] The laminate may include only one membrane leaf, but preferably has a structure in which a plurality of the membrane leaves are laminated. When the laminate has a structure in which a plurality of the membrane leaves are laminated, each component and separation membrane may be repeatedly laminated on the membrane laminate section, such as a permeate-side channel member 6, a separation membrane 4, etc.

[0035] As described above, within the membrane leaf, a permeate-side plugging part 5 may be installed between the permeate-side flow path member 6 and the separation membrane 4. In addition, in the laminate having a structure in which a plurality of membrane leaves are stacked, a permeate-side plugging part may be installed at the interface between one membrane leaf and another membrane leaf stacked on the first membrane leaf. In other words, a permeate-side plugging part 5 may be installed between the permeate-side flow path member 6 on the side of the first membrane leaf on which another membrane leaf is stacked, and the separation membrane 4 on the side of the other membrane leaf on the first membrane leaf side.

[0036] The number of membrane leaves included in the laminate is not particularly limited and may be, for example, 2 to 100, 5 to 50, or 10 to 30. The uppermost and lowermost surfaces of the laminate are preferably permeation-side channel members 6, and in this case, the uppermost permeation-side channel member 6 constitutes a membrane leaf.

[0037] The laminate has a supply-side plugging portion 3 between the separation membrane 4 and the supply-side channel member 2. The separation membrane 4 may include a porous layer in addition to a separation functional layer. In the supply-side plugging portion 3, the separation membrane 4 and the supply-side channel member 2 are bonded together at the locations where they come into contact with each other via the supply-side plugging portion 3. Hereinafter, the locations where they come into contact are also referred to as "adhesive portions." Therefore, the peel adhesive strength of the supply-side plugging portion 3 can also be said to be the adhesive strength of the adhesive portion. When a raw material fluid flows through the supply-side channel member 2, pressure is generated in the direction of the separation membrane 4.

[0038] The supply-side plugs 3 also function to prevent mixing of the fluid flowing through the supply-side channel member 2 and the fluid flowing through the permeate-side channel member 6. The fluid flowing through the supply-side channel member 2 is, for example, a feed fluid and a non-permeated fluid that has not permeated the separation membrane 4. The fluid flowing through the permeate-side channel member 6 is, for example, a permeated fluid that has permeated the separation membrane 4, and a sweep fluid that is supplied to the permeate-side channel member 6 and discharged together with the permeated fluid. The sweep fluid is a fluid that is inactive with respect to the separation functional layer of the separation membrane 4.

[0039] The permeate-side plugging sections 5 may be provided, as necessary, so as to include positions corresponding to the stacking positions of the permeate-side flow path members 6 in the stacking direction of the laminate. The "positions corresponding to the stacking positions of the permeate-side flow path members 6" refers to positions occupied by the permeate-side flow path members 6, as well as positions occupied by extended portions of the permeate-side flow path members 6 when the permeate-side flow path members 6 are extended in the direction along the plane of the laminate. The permeate-side plugging sections 5 may be formed so as to include the permeated portions, with the plugging material for forming the permeate-side plugging sections 5 permeating into the permeate-side flow path members 6.

[0040] The end of the supply-side channel member 2 may be provided with tape to prevent seepage of the plugging material used to form the permeate-side plugging sections 5. The tape is preferably provided on the end of the supply-side channel member 2 on the side facing the separation membrane 4. When separation membranes 4 are disposed on both sides of the supply-side channel member 2, the tape may be provided on both sides of the end of the supply-side channel member 2. Similarly, the end of the permeate-side channel member 6 may be provided with tape to prevent seepage of the supply-side plugging material used to form the supply-side plugging sections 3. Note that when the plugging material used to form the supply-side plugging sections 3 and / or the permeate-side plugging sections 5 is double-sided tape, there is no need to use tape to prevent seepage.

[0041] Each layer of the laminate has an edge on its surface. In this specification, the edge refers to a region of the surface of each layer that is a certain distance from the outer periphery of the layer. The certain distance is not particularly limited as long as it does not interfere with the effect of the separation membrane element, and may be, for example, 1% or less, 5% or less, or 10% or less of the distance between the opposing sides. In one embodiment, the region that becomes the edge may be 0.5% or more of the distance between the opposing sides. The edge may exist not only on the upper surface of the laminate, i.e., in the direction toward the top surface 7c of the container 7 that constitutes the separation membrane element, but also on the lower surface, i.e., in the direction toward the bottom surface 7a of the container 7. It is preferable that the certain distance between the upper edge and the lower edge of the same layer is the same.

[0042] Here, the end of the laminate in the direction in which the supply gas passes is referred to as the second end, and the end in the direction in which the permeation gas passes is referred to as the first end. Therefore, each layer included in the laminate has two first ends and two second ends on at least one surface. In this specification, the term "first end of the laminate" refers to the first ends of all layers included in the laminate. The same applies to the second ends.

[0043] The permeate-side plugging members 5 may be provided at the first end of the laminate in addition to the second end. When the permeate-side plugging members 5 are provided at the first end, they are preferably provided along the entire one side of the laminate constituting the first end in a plan view. That is, the permeate-side plugging members 5 provided at the first end are preferably provided along the first end of the laminate. The second permeate-side plugging members 5 provided at the first end may also be provided at a position corresponding to the stacking position of the permeate-side flow path member 6 in the stacking direction of the laminate, and may be formed so that the plugging material permeates into the permeate-side flow path member 6 and includes this permeated portion. When the permeate-side plugging members 5 are also provided at the first end, the permeate-side plugging members 5 may be provided at the two second end portions and at one end portion of the first end that is located on the side opposite to the direction in which the permeate gas is discharged, and the permeate-side plugging members 5 at the second end and the first end may be connected (for example, U-shaped) in a plan view.

[0044] The supply-side plugging portion 3 and the permeation-side plugging portion 5 are preferably bonded together at a position where the plugging portions intersect in a plan view. Hereinafter, the position where the plugging portions intersect is also referred to as an "intersection position." In the laminate, the intersection position can be provided at a corner of the laminate in a plan view.

[0045] 9 , the vessel 7 may have a first supply port 9 communicating with the supply-side channel member 2 of the laminate and for supplying a raw material fluid, a first outlet 10 communicating with the supply-side channel member 2 of the laminate and for discharging a non-permeating fluid, and a second outlet 12 communicating with the permeate-side channel member 6 of the laminate and for discharging a permeating fluid. The vessel 7 may further have a supply and outlet 11 communicating with the permeate-side channel member 6 of the laminate. The supply and outlet 11 may be used as a second supply port for supplying a sweep fluid or as a third outlet for discharging a permeating fluid.

[0046] The separation membrane element 1 may be configured such that the stack is disposed so that its second end faces the side wall 7b of the vessel 7, on which the first supply port 9 and the first discharge port 10 are formed. Alternatively, the separation membrane element 1 may be configured such that the stack is disposed so that its first end faces the side wall 7b of the vessel 7, on which the second discharge port 12 is formed. When the supply and discharge port 11 is not used or the vessel 7 does not have the supply and discharge port 11, a permeate-side plugging part 5 may be formed on the side of the first end of the stack on which the supply and discharge port 11 is formed. When the vessel 7 has the supply and discharge port 11 and uses the supply and discharge port 11, not forming a permeate-side plugging part 5 at the first end of the stack allows a sweep fluid to be supplied to the permeate-side channel member 6 or a permeate fluid to be discharged from the supply and discharge port 11.

[0047] When a sweep fluid is supplied to the separation membrane element 1, the sweep fluid is supplied to the permeate-side channel member 6, passes through the permeate-side channel member 6, and is discharged to the outside of the separation membrane element 1. More specifically, for example, when the separation membrane element 1 has the second outlet 12, the sweep fluid is discharged from the first end of the stack on the second outlet 12 side through the second outlet 12 to the outside of the separation membrane element 1.

[0048] Furthermore, by having the above-described configuration, the separation membrane element 1 can remove CO2 and the like from harmful gases such as exhaust gases. Such an effect also contributes to the achievement of, for example, Goal 7 "Affordable and clean energy," Goal 12 "Ensure sustainable consumption and production patterns," and Goal 13 "Take urgent action to combat climate change" of the Sustainable Development Goals (SDGs) advocated by the United Nations.

[0049] When the supply-side plugging portion 3 and the permeation-side plugging portion 5 are bonded to each other at the intersections of the first end portion and the second end portion (i.e., at the four corners of the laminate), the adhesiveness of the supply-side plugging portion 3 can be improved at the intersections, which makes it easier to further improve the airtightness of the supply-side plugging portion 3.

[0050] The supply-side plugging section 3 and the permeate-side plugging section 5 can be formed using a plugging material. The supply-side plugging section 3 and the permeate-side plugging section 5 may each independently use an adhesive or double-sided tape as the plugging material. When an adhesive is used, the adhesive may be a dried or cured adhesive layer.

[0051] The feed-side plugging portion 3 preferably has a peel strength of 0.5 N or more, more preferably 5.0 N or more, and even more preferably 10.0 N or more, under conditions of a temperature of 60°C and a humidity of 85% RH. The upper limit of the peel strength is not particularly limited and may be, for example, 20.0 N or less. A peel strength of 0.5 N or more can suitably prevent peeling of the feed-side plugging portion 2 when gas permeates the separation membrane element. The peel strength of the feed-side plugging portion 3 is measured by a method conforming to JIS K 6854-1. Thus, the peel strength and the peel adhesion strength are different parameters that are measured at the same temperature and humidity but using different measurement methods.

[0052] The sealing material can be a double-sided tape, an adhesive, or the like. The resin contained in the adhesive is not particularly limited as long as it can provide a peel adhesive strength of 0.5 N / 25 mm or more. Examples of resins contained in the adhesive include epoxy resins, urethane resins, silicone resins, vinyl chloride copolymer resins, vinyl chloride-vinyl acetate copolymer resins, vinyl chloride-vinylidene chloride copolymer resins, vinyl chloride-acrylonitrile copolymer resins, butadiene-acrylonitrile copolymer resins, polyamide resins, polyvinyl butyral resins, polyester resins, cellulose derivative (nitrocellulose, etc.) resins, styrene-butadiene copolymer resins, various synthetic rubber (elastomer) resins, phenolic resins, urea resins, melamine resins, phenoxy resins, and urea-formamide resins. Among these, the sealing material is preferably an epoxy resin (resin for epoxy adhesives), and more preferably a two-component mixed epoxy adhesive. In the case of double-sided tape, a structural adhesive tape made of acrylic foam coated with acrylic adhesive can be used. When using double-sided tape, the double-sided tape is stuck on the separation membrane, the release paper of the double-sided tape is peeled off, and then another separation membrane is stuck on.

[0053] The supply-side plugging section 3 and the permeate-side plugging section 5 may be formed of the same plugging material or different plugging materials. That is, for example, the plugging material of the supply-side plugging section 3 may be double-sided tape and the plugging material of the permeate-side plugging section 5 may be adhesive, or the plugging material of the supply-side plugging section 3 may be adhesive and the plugging material of the permeate-side plugging section 5 may be double-sided tape. Furthermore, both the plugging material of the supply-side plugging section 3 and the plugging material of the permeate-side plugging section 5 may be double-sided tape or adhesive.

[0054] The separation membrane element can separate a specific fluid component from a feed fluid containing at least the specific fluid component. The feed fluid, the specific fluid component, the permeate fluid, the non-permeate fluid, and the sweep fluid may each independently be a gas or a liquid. The separation membrane element is preferably a gas separation membrane element, and is preferably one that selectively allows the specific gas component to permeate from the feed gas.

[0055] The specific fluid component is preferably an acid gas. Acid gases include carbon dioxide (CO2), hydrogen sulfide (H2S), sulfur oxides (SO2), and the like. x ), and nitrogen oxides (NO x ) and the like. The specific gas component is preferably carbon dioxide or hydrogen sulfide, and more preferably carbon dioxide. Examples of the raw material gas include gases containing acidic gases such as residual exhaust gas from synthesis gas synthesized in plants that produce hydrogen or urea, natural gas, biogas, and combustion exhaust gases emitted from power plants, waste disposal sites, cement factories, etc.

[0056] This separation membrane element has an effective membrane area of ​​0.1 m 2 It is preferable that it is 12.0m or more. 2 More preferably, it is 36.0m or more. 2 It is more preferable that the effective membrane area is 500.0 m or more. 2 Preferably, it is less than 100.0m 2 It is more preferable that it is 50.0m or less. 2 It is more preferable that the effective membrane area is within the above ranges. The effective membrane area means the membrane area that can be used for gas separation. It is preferable that the effective membrane area is within these ranges from the viewpoint that a separation device with sufficient performance can be easily manufactured using the separation membrane element.

[0057] <Method of manufacturing the separation membrane element> The method for producing the separation membrane element will be described below with reference to Figures 2 to 9. In Figures 2 to 9, L represents the length direction of the container, W represents the width direction of the container, and H represents the height direction of the container.

[0058] The separation membrane element 1 can be manufactured by stacking a permeate-side flow path member 6, a separation membrane 4, a feed-side plugging section 3, and a feed-side flow path member 2 in the storage space of a container 7 to form a laminate. Hereinafter, as an example of the present separation membrane element, a separation membrane element in which the laminate, which is rectangular in plan view, is stored in a prismatic container 7 shown in Fig. 9 will be given, and an example of its manufacturing method will be described. The storage space of the container 7 is a space surrounded by a bottom surface 7a, a side wall 7b, and an upper surface (top lid) 7c.

[0059] The method for producing the separation membrane element of the present invention is not particularly limited and may be any known method for producing a separation membrane element. Examples of the production method include the following methods (1) to (8).

[0060] (1) The membrane laminate is prepared in advance. For example, as shown in FIG. 2, a separation membrane 4 is laminated on each side of a supply-side flow path member 2 having supply-side plugging sections 3 on both sides of two opposing ends, and the supply-side flow path member 2 and the separation membrane 4 are bonded together via the supply-side plugging sections 3, thereby preparing the membrane laminate. The separation layer 4 also has a separation functional layer. Therefore, in the membrane laminate obtained in (1), the supply-side plugging sections 3 are disposed between the separation functional layer and the supply-side flow path member 2.

[0061] There are no particular limitations on the method for preparing the supply-side flow path member 2 having the supply-side sealing portions 3, and examples thereof include a method of applying a sealing material along two opposing end portions of the supply-side flow path member 2 to form the supply-side sealing portions 3. Furthermore, before forming the supply-side sealing portions 3 at the two opposing end portions of the supply-side flow path member 2, a first tape may be attached to both surfaces of the two end portions to prevent seepage of the sealing material.

[0062] (2) Prepare a container 7' with its top surface (top lid) open as shown in FIG. 3. Here, the container 7' with its top surface (top lid) open is composed of a bottom surface 7a and sidewalls 7b, and has a storage space for storing the components that make up the laminate. The storage space is surrounded by the bottom surface 7a and sidewalls 7b and has the same height as the sidewalls 7b. The container 7' with its top surface (top lid) open may have guide members 8 for positioning the components stored in the storage space. If the storage space of the container 7' with its top surface (top lid) open is prismatic, the guide members 8 are preferably provided at the corners of the container 7' with its top surface (top lid) open, as shown in FIG. 3. Furthermore, it is preferable that the container 7' and the container 7 with the top surface (top lid) open have a first supply port 9, a first discharge port 10, a supply and discharge port 11, and a second discharge port 12 on each of the four side wall portions 7b, as shown in Figures 2 to 9.

[0063] (3) As shown in Fig. 4, inside the container 7' prepared in (2) with its upper surface (top lid) open, i.e., on the bottom surface 7a, a permeate-side flow path member 6 having permeate-side plugging sections 5 at two opposing ends is placed. Here, the upper surface refers to the surface of the permeate-side flow path member 6 that faces the bottom surface 7a. The permeate-side plugging sections 5 may be formed before or after the permeate-side flow path member 6 is placed on the bottom surface 7a.

[0064] The method for forming the permeate-side plugging parts 5 is not particularly limited, and examples thereof include a method of applying a plugging material along two opposing end parts of the permeate-side flow path member 6 to form the permeate-side plugging parts 5. The two opposing end parts preferably extend parallel to the longitudinal direction L of the container, as shown in Fig. 4. Furthermore, before forming the permeate-side plugging parts 5 at the two opposing end parts of the permeate-side flow path member 6, a second tape may be attached to the two opposing end parts to prevent seepage of the plugging material.

[0065] (4) As shown in Fig. 5, the membrane stack prepared in (1) above is placed on the upper surface of the permeate-side flow path member 6 placed on the bottom surface 7a in (3) above, so that one separation membrane 4 of the membrane stack and the permeate-side flow path member 6 are stacked via a permeate-side plugging 5. In this case, as shown in Fig. 5, it is preferable to stack the membrane stack so that the end of the membrane stack where the feed-side plugging 3 is formed is the end extending parallel to the width direction W of the container. In addition, the separation layer 4 has a separation functional layer. Therefore, in the stack obtained in (4), a permeate-side plugging 5 is placed between the separation functional layer and the permeate-side flow path member 6.

[0066] (5) As shown in Fig. 6, a permeate-side flow path member 6 having permeate-side plugs 5 at two opposing ends is installed on the upper surface of the membrane stack installed in (4) above, in the same manner as in (3) above. The upper surface of the membrane stack refers to the surface facing the bottom surface 7a of the membrane stack, similar to the upper surface of the permeate-side flow path member 6. As a result, a container 7' is obtained in which the membrane leaf is stacked on the bottom surface 7a and the upper surface (top lid) is open.

[0067] (6) As shown in Fig. 7, the membrane stack prepared in (1) above is placed on the upper surface of the permeate-side flow path member 6 placed in (5) above by the same method as in (4) above, so that one separation membrane 4 of the membrane stack and the permeate-side flow path member 6 are stacked via the permeate-side plugging part 5. In this case, as in (4) above, the separation layer 4 has a separation functional layer, so that in the stack obtained in (6) the permeate-side plugging part 5 is placed between the separation functional layer and the stacked permeate-side flow path member 6.

[0068] (7) Using the same method as in (5) and (6), the membrane stack is installed on the upper surface of the permeate-side flow path member 6 installed in (6). Subsequently, the step of installing a permeate-side flow path member 6 equipped with permeate-side pluggings 5 ​​at two opposing ends on the upper surface of the membrane stack is repeated. As a result, a container 7' (FIG. 8) is obtained in which a plurality of membrane leaves are stacked on the bottom surface 7a and the upper surface (top lid) is open. In this case, as in (4) and (6), the separation layer 4 has a separation functional layer, and therefore, in the stack obtained in (7), permeate-side pluggings 5 ​​are disposed between the separation functional layer and the stacked permeate-side flow path member 6.

[0069] (8) As shown in FIG. 9, an upper surface portion (upper lid) 7c is attached to the container 7' obtained in (7) to form the container 7. As a result, the separation membrane element 1 is produced. Here, the method for attaching the upper surface portion (upper lid) 7c is not particularly limited. For example, the method may include applying an adhesive to the uppermost surfaces of the plurality of membrane leaves, attaching the upper surface portion (upper lid) 7c, subsequently filling the gaps between the upper surface portion (upper lid) 7c and the side wall portion 7b and the guide portion 8 with adhesive, and then curing the adhesive.

[0070] In the manufacturing method, the peel adhesive strength of the supply-side sealing portion 3 is set to a predetermined range of 0.5 N / 25 mm or more, and the linear expansion coefficient of the container 7 is set to 60.0 × 10 -6 By setting the temperature within a predetermined range of 1 / °C or less, the separation membrane element 1 can be manufactured.

[0071] One method for adjusting the peel strength within the predetermined range is to select a suitable substance as the sealing material for the supply-side sealing portion 3. An example of such a substance is a substance that is resistant to deterioration even in high-temperature and high-humidity environments and has excellent adhesive properties. The substance may be, for example, the sealing material described above. Another method for adjusting the peel strength within the predetermined range is to optimize the conditions for forming the sealing material portion when forming the supply-side sealing portion so as to increase the peel strength.

[0072] One method for adjusting the linear expansion coefficient to fall within the predetermined range is to select a suitable material for the container 7. The material may be one that has high heat resistance and is resistant to deformation even in a high-temperature environment. The material will be described later.

[0073] Each of the components constituting the separation membrane element will be described in more detail below.

[0074] (container) The container 7 contains the laminate. The container 7 has a top surface (top lid) 7c, a bottom surface 7a, and a side wall 7b connecting the top surface (top lid) 7c and the bottom surface 7a. The container 7 can define a storage space by the top surface (top lid) 7c, the bottom surface 7a, and the side wall 7b. The top surface (top lid) 7c and the bottom surface 7a extend in a direction perpendicular to the stacking direction of the laminate, and the side wall 7b extends in the stacking direction of the laminate. The shape of the container 7 is not particularly limited, and the top surface 7c and the bottom surface 7a may be polygonal, such as rectangular, or may be circular. The side wall 7b may be prismatic or cylindrical.

[0075] The container 7 may have guide portions 8 for positioning the components constituting the stack. When the side wall portion 7b is prismatic, the guide portions 8 are preferably provided at the corners of the side wall portion 7b.

[0076] When the container 7 has the first supply inlet 9, the supply and discharge outlet 11, the first discharge outlet 10, and the second discharge outlet 12, the first supply inlet 9, the supply and discharge outlet 11, the first discharge outlet 10, and the second discharge outlet 12 may all be provided on the side wall 7b of the container. Alternatively, the first supply inlet 9, the supply and discharge outlet 11, the first discharge outlet 10, and the second discharge outlet 12 may be provided on the top surface (top lid) 7c or the bottom surface 7a.

[0077] The top surface (lid) 7c, bottom surface 7a, and sidewall 7b of the container 7 can be made of resin, glass, metal, ceramic, or other materials. Examples of resins include polycarbonate, acrylic resin, fluororesin, polybutylene succinate (PBS), polyethylene terephthalate (PET), polyvinyl chloride (PVC), polystyrene (PS), acrylonitrile-butadiene-styrene copolymer (ABS), polyphenylene sulfide (PPS), polyethersulfone (PES), polysulfone (PSF), polyacrylonitrile (PAN), polyphenylene oxide (PPO), polyamide (PA), polyimide (PI), polyetherimide (PEI), polyetheretherketone (PEEK), and polypropylene (PP), as well as fiber-reinforced resins made by mixing these resins with glass or other fibers. Examples of metals include stainless steel (SUS), aluminum, copper, and other materials. The components of the container 7 can be made of the same material or different materials.

[0078] The thickness of each of the components constituting the container 7 is preferably 5 mm or more from the viewpoint of suppressing deformation of the container 7 due to thermal expansion. Here, the thickness of each component refers to the thickness of the container 7 itself. Therefore, the thickness of the container 7 is preferably 5 mm or more from the viewpoint of suppressing deformation of the container 7 due to thermal expansion.

[0079] (separation membrane) The separation membrane 4 is not particularly limited as long as it has a separation functional layer that selectively separates specific fluid components contained in the raw fluid and is a known membrane that can selectively permeate specific fluid components from the raw fluid. The separation membrane 4 can be, for example, an ultrafiltration membrane, a nanofiltration membrane, a reverse osmosis membrane, a dialysis membrane, a forward osmosis membrane, a solution-diffusion membrane, a facilitated transport membrane, or the like. A solution-diffusion membrane is a membrane that selectively permeates molecules by utilizing the differences in the solubility and diffusibility of fluid molecules. A facilitated transport membrane is a membrane that contains a substance that promotes the solubility and / or diffusibility of fluid molecules. The separation membrane 4 is preferably a solution-diffusion membrane.

[0080] The separation membrane 4 has a separation functional layer and may optionally have a porous layer. The separation membrane 4 may have one or more porous membrane layers, or may have two or more porous membrane layers, or may have three or more porous membrane layers. The porous membrane may be provided on one or both sides of the separation functional layer. The porous membrane provided on one or both sides of the separation functional layer may be one layer, or may have two or more porous membrane layers. Furthermore, the separation membrane 4 may have a support layer for reinforcement, if necessary.

[0081] When the separation membrane 4 has a porous membrane on only one side, it is preferable to laminate the separation membrane 4 and the supply-side flow path member 2 in the membrane stack section so that the separation functional layer side of the separation membrane 4 faces the supply-side flow path member 2.

[0082] The thickness of separation membrane 4 is preferably 10 to 600 μm, more preferably 10 μm to 550 μm, and even more preferably 10 to 510 μm. If the thickness of separation membrane 4 is within this range, the membrane thickness will be thin and specific fluid components such as carbon dioxide can be sufficiently separated from the raw fluid. Furthermore, separation membrane 4 having a thickness within this range can be preferably used as a separation membrane that constitutes a plate-and-frame separation membrane element.

[0083] (separation functional layer) The separation functional layer can be selected depending on the type of membrane. The separation functional layer is preferably a layer formed using a composition containing a resin. Examples of the resin include polyacrylic acid, polyamide, cellulose acetate, polysulfone, polyethersulfone, vinylidene fluoride, polyacrylonitrile, polyvinyl chloride-polyacrylonitrile copolymer, epoxy resin, polyimide, polyvinyl alcohol, polysiloxane, polyether block amide copolymer, and polyethylene oxide. The polyacrylic acid may be crosslinked polyacrylic acid or uncrosslinked polyacrylic acid.

[0084] The separation functional layer may be a gel layer. The gel layer contains a hydrophilic resin such as polyacrylic acid, and may further contain an amino acid, an aminosulfonic acid, and / or an aminophosphonic acid. The gel layer may contain a surfactant for adjusting the wettability of the porous membrane. When the specific fluid component is a gas, the gel layer may further contain an alkali metal compound and / or a hydration reaction catalyst for improving the reaction rate between the specific gas component and the alkali metal compound.

[0085] The separation functional layer can be produced, for example, by applying a coating liquid containing the resin and medium onto a porous membrane. Methods for applying the coating liquid onto a porous membrane include slot die coating, spin coating, bar coating, die coating, blade coating, air knife coating, gravure coating, roll coating, spray coating, dip coating, comma roll coating, kiss coating, screen printing, inkjet printing, etc.

[0086] The thickness of the separation functional layer is preferably 1 to 1000 nm, more preferably 10 to 500 nm, and even more preferably 100 to 400 nm. When the thickness of the separation functional layer is within the above range, specific fluid components such as carbon dioxide can be sufficiently separated from the raw material fluid.

[0087] (porous membrane) The porous membrane can be a support layer for supporting the separation functional layer or a protective layer for protecting the separation functional layer. The porous membrane can be in direct contact with the separation functional layer. The porous membrane preferably has porosity with high fluid permeability so as not to act as a diffusion resistance for the raw fluid supplied to the separation functional layer or a specific fluid component contained in the raw fluid.

[0088] The porous membrane is preferably made of a resin material or an inorganic material. Examples of the resin material constituting the porous membrane include polyolefin resins such as polyethylene (PE) and polypropylene (PP); fluorine-containing resins such as polytetrafluoroethylene (PTFE), polyvinyl fluoride (PVF), and polyvinylidene fluoride (PVDF); polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate; polystyrene (PS), polyethersulfone (PES), polyphenylene sulfide (PPS), polysulfone (PSF), polyacrylonitrile (PAN), polyphenylene oxide (PPO), polyamide (PA), polyimide (PI), polyetherimide (PEI), polyetheretherketone (PEEK), high-molecular-weight polyester, heat-resistant polyamide, aramid, polycarbonate, and mixtures of two or more of these resin materials. Among these, from the viewpoint of water repellency and heat resistance, it is preferable to contain at least one of polyolefin resin and fluorine-containing resin, and it is more preferable to contain one or more of polyethylene, polypropylene, and polytetrafluoroethylene. Examples of inorganic materials constituting the porous membrane include metal, glass, ceramics, etc.

[0089] The porous membrane is not particularly limited as long as it is a porous body. The porous membrane may be a porous sheet-like body such as a porous resin film, nonwoven fabric, woven fabric, foam, mesh, or net. These porous bodies can also be used as a reinforcing support layer.

[0090] The porous membrane of the separation membrane 4 may be, for example, one or more layers of porous resin film laminated on one side of the separation functional layer and one or more layers of nonwoven fabric laminated on the other side of the separation functional layer.

[0091] (Feed-side channel member and permeation-side channel member) The feed-side channel member 2 and the permeate-side channel member 6 preferably have the following functions (a) and (b). (a) a function of promoting turbulence of the feed fluid and the permeated fluid that has permeated the separation membrane 4, i.e., surface renewal of the membrane surface, thereby increasing the membrane permeation rate of the permeated fluid in the feed fluid; (b) A function of minimizing the pressure loss of the raw fluid supplied and the permeated fluid that has permeated the separation membrane 4.

[0092] The feed-side channel member 2 and the permeate-side channel member 6 preferably function as spacers that form channels for the feed fluid and the permeated fluid, and also function to generate turbulence in the feed fluid and the permeated fluid. For this reason, net-like, mesh-like, or other mesh-like members are preferably used as the feed-side channel member 2 and the permeate-side channel member 6. The shape of the unit lattice of the mesh changes the fluid channel depending on the shape of the mesh, so it is preferable to select from shapes such as a square, rectangle, rhombus, and parallelogram depending on the purpose.

[0093] The compressive deformation of the permeate-side flow path member 6, as measured according to JIS K 7181, is 0.40 mm or less, preferably 0.35 mm or less, and more preferably 0.30 mm or less. There is no particular lower limit to the compressive deformation, but it may be, for example, 0.10 mm or more. When the compressive deformation is 0.40 mm or less, peeling of the feed-side plugs 3 is unlikely to occur even when gas permeates the separation membrane element 1. The compressive deformation of the permeate-side flow path member can be measured by a known method.

[0094] The materials for the feed-side channel member 2 and the permeate-side channel member 6 are not particularly limited, and are preferably heat-resistant materials that can withstand the operating temperature conditions of a separation apparatus in which the separation membrane element 1 is installed. The feed-side channel member 2 and the permeate-side channel member 6 may each independently have a single-layer structure or a multilayer structure. The feed-side channel member 2 and the permeate-side channel member 6, which have a multilayer structure, preferably have a structure in which one or more types of mesh layers are stacked, and the stacked mesh layers may have different mesh structures. Preferably, the permeate-side channel member 6 has a single-layer structure.

[0095] In this specification, the phrase "the permeate-side channel member 6 has a single-layer structure" means that the permeate-side channel member 6 does not have multiple layers. In other words, this means that the permeate-side channel member 6 is made of a single mesh or net, and does not mean that the permeate-side channel member 6, the separation membrane 4, and the feed-side channel member 2 are not laminated in the separation membrane element 1. Furthermore, the phrase "the permeate-side channel member 6 has a multi-layer structure" means that the permeate-side channel member 6 is made of multiple meshes or nets.

[0096] In one embodiment of the present invention, the permeate-side channel member 6 is preferably in a mesh form. When the permeate-side channel member 6 is in a mesh form and has a multilayer structure having two or more layers, it is preferable that the number of meshes in each layer of the permeate-side channel member 6 is the same. If the number of meshes in each layer is the same, deformation of the permeate-side channel member 6 due to one layer penetrating into another layer is less likely to occur, and the compressive strength of the permeate-side channel member 6 is improved. When the permeate-side channel member 6 has a single-layer structure, or when the permeate-side channel member 6 has a multilayer structure and the number of meshes in each layer is the same, the number of meshes in the permeate-side channel member 6 is preferably 18 meshes or more. The upper limit of the mesh number is not particularly limited, but it may be, for example, 150 meshes or less.

[0097] In another embodiment of the present invention, when the permeate-side channel member 6 is mesh-like and has a multilayer structure having two or more layers, the layers of the permeate-side channel member 6 may have different mesh counts. In this case, the mesh count of the permeate-side channel member 6 is preferably 50 meshes or more. There is no particular upper limit to the mesh count, but it may be, for example, 150 meshes or less. When the mesh count of the permeate-side channel member 6 is 50 meshes or more, the mesh openings between the meshes are sufficiently small, making it difficult for one layer to penetrate into another layer, thereby preventing deformation of the permeate-side channel member 6.

[0098] (1st tape, 2nd tape) The first tape and the second tape are tapes used to prevent seepage of the sealing material. The first tape and the second tape can be made of a material that is impermeable to the sealing material. Examples of such materials include polypropylene, polyimide, polytetrafluoroethylene, glass fiber, and polyester. The materials forming the first tape and the second tape may be the same or different. The first tape and the second tape are used during the production of the separation membrane element, and may be removed or may remain when the separation membrane element is used.

[0099] [Embodiment 2: Separation device] A separation device according to one embodiment of the present invention (hereinafter referred to as "the separation device") comprises the separation membrane element, a first supply section and a first discharge section communicating with the supply side flow path member, and a second discharge section communicating with the permeation side flow path member.

[0100] By being equipped with this separation membrane element, this separation device can obtain the target fluid component with high selectivity without leakage of the supplied gas even when a high-temperature and high-humidity fluid is supplied.

[0101] The separation apparatus can have one or more separation membrane elements. The arrangement and number of separation membrane elements to be provided in the separation apparatus can be selected depending on the required throughput, the recovery rate of specific fluid components, the size of the space where the separation apparatus is to be installed, etc.

[0102] The present separation device may further include a supply / discharge part that communicates with the permeate-side channel member 6 of the separation membrane element 1 .

[0103] The first supply unit is an inlet for supplying a raw fluid to the supply-side channel member 2, and when the separation membrane element 1 has a first supply port 9, it can be connected to the first supply port 9. The first discharge unit is an outlet for discharging a non-permeating fluid flowing through the supply-side channel member 2, and when the separation membrane element 1 has a first discharge port 10, it can be connected to the first discharge port 10. The second discharge unit is an outlet for discharging a permeating fluid flowing through the permeate-side channel member 2, and when the separation membrane element 1 has a second discharge port 12, it can be connected to the second discharge port 12. The supply and discharge unit can be used as a second supply unit, which is an inlet for supplying a sweep fluid to the permeate-side channel member, or as a third discharge unit for discharging a permeating fluid. When the separation membrane element has a supply and discharge port 11, the supply and discharge unit can be connected to the supply and discharge port 11.

[0104] An embodiment of the present invention may include the following features. <1> A plate-and-frame separation membrane element including a separation membrane having a separation functional layer, a feed-side channel member, and a permeate-side channel member in a container, the separation functional layer is a layer that selectively separates a specific fluid component contained in the raw material fluid, a sealing portion is disposed between the supply-side channel member and the separation membrane, The peel adhesive strength of the sealing part is 0.5 N / 25 mm or more, The linear expansion coefficient of the container is 60.0 × 10 -6 / ℃ or less. (Here, the peel adhesive strength is measured by a T-peel test conducted in accordance with JIS K 6854-3 on a 100 mm × 25 mm test piece for measuring peel adhesive strength cut out from the sealed portion, under conditions of a temperature of 60°C and a humidity of 85% RH; and the linear expansion coefficient is measured in accordance with JIS R 1618 on a 7 mm wide × 10 mm long × 5 mm thick test piece for measuring linear expansion coefficient cut out from the side wall of the container, under conditions of a measurement direction: lengthwise, a temperature range: room temperature to 150°C (however, if the softening point or melting point of the test piece for measuring linear expansion coefficient is 150°C or lower, the temperature is measured to the temperature just before that point), a temperature increase / decrease rate: 5°C / min, a load: approximately 0.05 N, and a measurement atmosphere: He.) <2> The peel adhesive strength of the sealing part is 0.6 N / 25 mm or more. <1> The plate-and-frame separation membrane element according to claim 1. <3> The thickness of the container is 5 mm or more. <1> or <2> The plate-and-frame separation membrane element according to claim 1. <4> The thickness of the separation membrane is 10 to 600 μm. <1> ~ <3> 1. A plate-and-frame separation membrane element according to any one of the above. <5> The raw material fluid is a gas. <1> ~ <4> 1. A plate-and-frame separation membrane element according to any one of the above. <6> The specific fluid component is an acid gas. <1> ~ <5> 1. A plate-and-frame separation membrane element according to any one of the above. <7> <1> ~ <6> a first supply section and a first discharge section communicating with the supply-side channel member; and a second discharge section communicating with the permeation-side channel member. [Example]

[0105] EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0106] [Methods for measuring various physical properties] Measurement of the physical properties and evaluation of the performance of the separation membrane elements described in Example 1 and Comparative Examples 1 and 2 were carried out by the following methods.

[0107] <Peel adhesive strength of supply side seal> The peel adhesive strength of the sealed portions of the separation membrane elements produced in Example 1 and Comparative Examples 1 and 2 was measured and calculated according to JIS K 6854-3, following the procedures 1. to 4. below. 1. The top surface (top lid) of the container was removed from the separation membrane element, and the stack housed in the container was taken out. Furthermore, of the 30 membrane leaves constituting the stack, a total of six membrane leaves were taken out, namely the 5th, 10th, 15th, 20th, 25th, and 30th membrane leaves from the bottom. Here, the Xth membrane leaf from the bottom refers to the order of stacking when the membrane leaf stacked directly on the bottom surface of the container is the first membrane leaf from the bottom. 2. The supply-side sealed portion of each of the six film leaves was cut out to a size of 100 mm x 25 mm, thereby obtaining six test pieces for measuring peel adhesive strength. 3. The maximum load [N] required to peel the supply-side seal of the test piece for measuring peel adhesion strength from the separation membrane was measured using a T-peel test. The magnitude of the measured load was taken as the peel adhesion strength [N / 25 mm] of each test piece for measuring peel adhesion strength. The T-peel test was carried out using an Intesco electric constant temperature and humidity precision testing machine under conditions of a temperature of 60°C and a humidity of 85% RH. 4. The average peel strength of each of the six test pieces for measuring peel strength measured in 3. was calculated, and the obtained average value was defined as the peel strength [N / 25 mm] of the supply-side sealed portion.

[0108] <Linear expansion coefficient of container> The linear expansion coefficient of the container of the separation membrane element was measured in accordance with JIS R 1618 by the following procedures 1 and 2. 1. The separation membrane element was disassembled, and a test piece for measuring the linear expansion coefficient, measuring 7 mm wide x 10 mm long x 5 mm thick, was cut out from the side wall of the container. 2. The linear expansion coefficient of the test piece for measuring the linear expansion coefficient obtained in 1. above was measured under the following conditions using a TMA device (NETZSCH TMA-402 F1 Hypersion) in compression measurement mode. From the linear expansion coefficient, the linear expansion coefficient of the container [×10 -6 / °C] was calculated in the temperature range of 25°C to 120°C.

[0109] (Measurement conditions) Measurement direction: lengthwise, Measurement mode: Compression mode Temperature program: Room temperature (25°C) → 150°C → Room temperature → 150°C → Room temperature Temperature increase / decrease rate: 5℃ / min Load: 0.05N Measurement atmosphere: He Number of cycles (N) when room temperature (25°C) → 150°C is considered as one cycle: 3 <Separation membrane element performance: Evaluation of selectivity> The CO2 / N2 selectivity of the separation membrane element was evaluated using the apparatus shown in Figure 10, following the steps 1 to 4 below. Figure 10 is a schematic diagram showing the configuration of the apparatus used to evaluate the performance of the separation membrane element used in the Examples. In Figure 10, a first supply port 9, a first discharge port 10, a supply / discharge port 11, and a second discharge port 12 are components that make up the separation membrane element 1. The apparatus is equipped with a supply section 17 communicating with the first supply port 9 located at one of the two ends parallel to the width direction W of the separation membrane element 1, and a discharge section 18 communicating with the first discharge port 10 located at the other end. The apparatus is also equipped with a supply section 19 communicating with the supply / discharge port 11 located at one of the two ends parallel to the length direction L of the separation membrane element 1, and a discharge section 20 communicating with the second discharge port 12 located at the other end. 1. Using the above-mentioned device, CO gas and N gas were supplied to the supply side of the separation membrane element 1 at a total flow rate of 20 NL / min so that the CO gas concentration was 10% by volume and the N gas concentration was 90% by volume, while the temperature of the separation membrane element 1 was maintained at 40° C. Here, the temperature of the gas supplied into the separation membrane element 1 was 40° C. and the humidity was 85% RH. 2. After step 1, the pressure on the supply side of the apparatus was adjusted to 101.3 kPaG (gauge pressure) using a back pressure regulator 13 installed in the discharge path for the non-permeate gas. The pressure on the permeate side of the apparatus was adjusted to −90 kPaG (gauge pressure) using a pressure reducing valve 14 and a pressure reducing pump 15. 3. After step 2 above, the flow rate of the gas that had permeated the separation membrane element 1 was measured using a flow meter installed on the outlet side of the permeation side. The flow rate of the gas that had permeated the separation membrane element 1 was measured when a steady state was reached after the performance evaluation test equipment had started operating. The CO2 and N2 concentrations of the permeated gas that had permeated the separation membrane element 1 were analyzed using gas chromatography (GC) 16, and the permeation flow rates of CO2 and N2 were calculated from the permeation flow rates. 4. Following the procedure in 3, the CO2 / N2 selectivity was calculated by dividing the CO2 permeation flow rate by the N2 permeation flow rate. The calculated CO2 / N2 selectivity was evaluated according to the following criteria. A: CO2 / N2 selectivity 20 or more B: CO2 / N2 selectivity less than 20 [Manufacturing Example 1: Preparation of Separation Membrane A] A separation functional layer (Pebax (registered trademark) polyether block amide copolymer), a porous substrate (polyacrylonitrile), and a PET nonwoven fabric reinforcing support layer were laminated in this order to obtain a composite membrane. The composite membrane was cut into a size of 119 mmL x 119 mmW to prepare a separation membrane.

[0110] [Example 1: Preparation of separation membrane A] (Preparation of components constituting the separation membrane element) A 119mmL x 119mmW PP mesh (Innovex Co., Ltd.; product name: 50-150PPN) was prepared as the permeate-side flow path member. A glass-fiber-reinforced polycarbonate (Sumika Polycarbonate Co., Ltd.; grade name: SF5201V, GF20%) container (external dimensions: 150mmL x 150mmW x 85mmH, internal dimensions of the four corner guides: 120mmL x 120mmW, bottom, sidewall, and top (lid) thickness: 5mm) was prepared. A 119mmL x 96mmW PP diamond net (SWM Co., Ltd.; product name: No. 1716) was prepared as the feed-side flow path member. A two-component mixed epoxy adhesive (Nagase ChemteX Corporation; Denatite 3324) was prepared as the permeate-side sealing material. A double-sided tape (manufactured by 3M, product name: Y4930) was prepared as a supply-side sealing material. In Example 1, the permeate-side flow path member, the container, the supply-side flow path member, the permeate-side sealing material, the supply-side sealing material, and the separation membrane prepared in Production Example 1 were used.

[0111] (Fabrication of separation membrane element) A separation membrane element was manufactured by carrying out the following methods (i) to (xiii). The manufactured separation membrane element is referred to as separation membrane element (1). The effective membrane area of ​​the separation membrane element (1) was 0.4 m 2 It was.

[0112] (i) First, a membrane laminate was prepared having a three-layer structure in which one supply-side flow path member was provided in the middle, and one separation membrane was laminated on each of the top and bottom of the supply-side flow path member via a supply-side plug formed from a supply-side plugging material. Specifically, the supply-side plugging material was applied to two opposing ends of one supply-side flow path member to form supply-side plugging parts. Next, one separation membrane was laminated on each of the top and bottom surfaces of the supply-side flow path member on which the supply-side plugging parts had been formed, thereby preparing the membrane laminate. Thirty membrane laminates were prepared.

[0113] (ii) The upper surface of the container, i.e., the top lid, was opened, and the container with the top lid open was prepared.

[0114] (iii) A permeate-side flow path member was placed inside the container prepared in (ii) with the top lid open, i.e., on the bottom surface thereof. Then, a permeate-side plugging material was applied to two opposing ends of the permeate-side flow path member that were parallel to the longitudinal direction L of the container, to form permeate-side plugging parts.

[0115] (iv) One membrane stack prepared in (i) was placed on the upper surface of the permeate-side flow path member placed in (iii) so that the end of the membrane stack where the feed-side plugging was formed was the end extending parallel to the width direction W of the container, opposite the end where the permeate-side plugging was formed.

[0116] (v) A permeate-side flow path member was placed on the upper surface of the membrane stack placed in (iv) in the same manner as in (iii), and then a permeate-side plugging material was applied to two opposing ends of the permeate-side flow path member, which were parallel to the longitudinal direction L of the container, to form permeate-side plugging sections.

[0117] (vi) In the same manner as in (iv), one membrane stack prepared in (i) was placed on the upper surface of the permeate-side flow path member placed in (v), such that the end of the membrane stack where the feed-side plugging was formed was the end extending parallel to the width direction W of the container, opposite the end where the permeate-side plugging was formed.

[0118] (vii) The membrane stack was placed on the upper surface of the permeate-side flow path member placed in the previous step, followed by placing a permeate-side flow path member on the upper surface of the membrane stack. Then, a permeate-side plugging material was applied to the two ends of the permeate-side flow path member to form permeate-side pluggings. This process was repeated until the number of membrane stacks contained in the stack housed in the container reached 30, and one permeate-side flow path member was placed on top of them. At this time, the membrane stack and the guides provided at the four corners of the container were sealed by the permeate-side flow path member. As in (v), permeate-side plugging material was applied to two opposing ends of the permeate-side flow path member that extended parallel to the length direction L of the container to form permeate-side pluggings. As in (vi), the membrane stack was placed so that the end of the membrane stack where the feed-side pluggings were formed was the end extending parallel to the width direction W of the container, opposite the end where the permeate-side pluggings were formed.

[0119] (viii) A permeate-side sealing material, which is an adhesive, was applied to two opposing ends of the last permeate-side flow path member installed in (vii), which were parallel to the longitudinal direction L of the container. Next, a top cover was installed on the container with the top cover open, and the permeate-side sealing material was applied to the gap between the top cover and the side wall portion of the container, which was a member other than the top cover. The permeate-side sealing material was then held at room temperature for 24 hours to harden. As a result, a separation membrane element was produced.

[0120] [Comparative Example 1] A separation membrane element was obtained by the same procedure as in Example 1, except that the supply-side sealing material was changed to double-sided tape, model number #880SWT, manufactured by Ebisu Chemical Co., Ltd., and the material of the container was changed to stainless steel (SUS). This separation membrane element is referred to as comparative separation membrane element (1). The effective membrane area of ​​the comparative separation membrane element (1) was 0.4 m 2 It was.

[0121] Comparative Example 2 A separation membrane element was obtained by the same procedure as in Example 1, except that the supply-side sealing material was changed to a two-component mixed epoxy adhesive (Denatite 3324, manufactured by Nagase ChemteX Corporation) and the material of the container was changed to polycarbonate (manufactured by Sumika Polycarbonate, grade name: 303-10). This separation membrane element is referred to as comparative separation membrane element (2). The effective membrane area of ​​the comparative separation membrane element (2) was 0.4 m 2 It was.

[0122] [Conclusion] Table 1 shows the physical properties and performance evaluation results of the separation membrane element (1) produced in Example 1 and Comparative Examples 1 and 2, as well as the comparative separation membrane element (1) and comparative separation membrane element (2). [Table 1]

[0123] As shown in Table 1, the separation membrane element (1) produced in Example 1 has a seal portion disposed between the feed-side flow path member and the separation functional layer, i.e., a feed-side seal portion, whose peel adhesive strength is 0.5 N / 25 mm or more, and a linear expansion coefficient of the container is 60.0 × 10 -6 / ℃ or less.

[0124] On the other hand, the comparative separation membrane element (1) produced in Comparative Example 1 had a peel adhesive strength of less than 0.5 N / 25 mm at the supply side sealing portion, and the comparative separation membrane element (2) produced in Comparative Example 2 had a linear expansion coefficient of the container of 60.0 × 10 -6 The value exceeded / ℃.

[0125] Therefore, the separation membrane element (1) corresponds to the separation membrane element of the present invention, while the comparative separation membrane element (1) and the comparative separation membrane element (2) do not correspond to the separation membrane element of the present invention.

[0126] Furthermore, as shown in Table 1, the separation membrane element (1) has higher CO2 / N2 selectivity in a high-temperature, high-humidity environment than the comparative separation membrane element (1) and the comparative separation membrane element (2). Therefore, the separation membrane element (1) does not have a reduced CO2 / N2 selectivity even when supplied with a high-temperature, high-humidity gas, and it is believed that no leakage of the supplied gas, which would be the cause of the reduced selectivity, occurs.

[0127] Therefore, it was found that the separation membrane element of the present invention can maintain good selectivity for the target fluid component even when a high-temperature and high-humidity fluid is supplied. [Industrial Applicability]

[0128] An embodiment of the present invention can be used as a component of a separation device that separates a target fluid component from a high-temperature and high-humidity fluid such as exhaust gas, and as the separation device itself. [Explanation of symbols]

[0129] 1 Separation membrane element 2. Supply side flow path member 3 Supply side sealing part 4 Separation membrane 5 Transmission side sealing part 6. Permeate side flow path member 7 Container 7´ Container with the top part (lid) open 7a Bottom part 7b Side wall part 7c Top part (upper lid) 8 Guide section 9 1st supply port 10 1st outlet 11 Supply outlet 12 2nd outlet 13 Back pressure regulator 14 Pressure reducing valve 15. Vacuum pump 16 Gas Chromatography (GC) 17 Supply section 18 Discharge section 19 Supply section 20 Discharge section

Claims

1. A plate-and-frame separation membrane element including a separation membrane having a separation functional layer, a feed-side channel member, and a permeate-side channel member in a container, the separation functional layer is a layer that selectively separates a specific fluid component contained in the raw material fluid, a sealing portion is disposed between the supply-side channel member and the separation membrane, The peel adhesive strength of the sealing portion is 0.5 N / 25 mm or more, The linear expansion coefficient of the container is 60.0×10 －６ / °C or less. (Here, the peel adhesive strength is measured by a T-peel test performed on a test piece for measuring peel adhesive strength having a size of 100 mm x 25 mm cut out from the sealed portion, under conditions of a temperature of 60°C and a humidity of 85% RH, in accordance with JIS K 6854-3; and the linear expansion coefficient is measured on a test piece for measuring linear expansion coefficient having a size of 7 mm width x 10 mm length x 5 mm thickness cut out from the side wall portion of the container, in accordance with JIS R 1618, under conditions of measurement direction: length direction, temperature range: room temperature to 150°C (however, if the softening point or melting point of the test piece for measuring linear expansion coefficient is 150°C or lower, up to the temperature just before that point), temperature increase / decrease rate: 5°C / min, load: approximately 0.05 N, and measurement atmosphere: He.)

2. 2. The plate-and-frame separation membrane element according to claim 1, wherein the peel adhesive strength of the sealing portion is 0.6 N / 25 mm or more.

3. 2. The plate-and-frame separation membrane element according to claim 1, wherein the thickness of the container is 5 mm or more.

4. 4. The plate-and-frame separation membrane element according to claim 1, wherein the separation membrane has a thickness of 10 to 600 μm.

5. 4. The plate-and-frame separation membrane element according to claim 1, wherein the raw material fluid is a gas.

6. 4. The plate-and-frame separation membrane element according to claim 1, wherein the specific fluid component is an acid gas.

7. A separation device comprising: the plate-and-frame separation membrane element according to any one of claims 1 to 3; a first supply section and a first discharge section communicating with the supply-side channel member; and a second discharge section communicating with the permeation-side channel member.

Images