Gas adsorption separation membrane and method for producing gas adsorption separation membrane

Abstract

To provide a gas adsorption separation membrane which can reduce energy consumption required for a gas separation process, and is excellent in gas separation performance, and a method for producing a gas adsorption separation membrane.SOLUTION: A gas adsorption separation membrane has an impermeable sheet which is spirally wound, and an ion exchange resin which is fixed to one surface or both surfaces of the impermeable sheet.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a gas adsorption separation membrane and a method for producing a gas adsorption separation membrane. [Background technology]

[0002] BACKGROUND ART From the viewpoint of combating global warming and preventing air pollution, attention has been focused on technologies for separating gases such as carbon dioxide, nitrogen oxides, and sulfur oxides from the atmosphere or from exhaust gases emitted from power plants and factories. For example, techniques using ion exchange resins in separation processes for separating carbon dioxide from the gas phase of the atmosphere, exhaust gases, etc. are being investigated (see Patent Documents 1 to 6). Ion exchange resins are usually used in a state where they are densely packed inside a resin tower (see, for example, Figure 1 of Patent Document 1), and components such as carbon dioxide contained in gas passed through the gaps in the ion exchange resin are separated by being adsorbed onto the ion exchange resin (see, for example, Figure 1 of Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 63-012323 [Patent Document 2] Special Publication No. 2015-507527 [Patent Document 3] Japanese Patent Application Publication No. 01-208310 [Patent Document 4] Japanese Patent Application Laid-Open No. 2007-190529 [Patent Document 5] Japanese Patent Application Laid-Open No. 2003-230812 [Patent Document 6] Japanese Patent Application Publication No. 63-016032 Summary of the Invention [Problem to be solved by the invention]

[0004] It is known that gas separation processes using ion exchange resins tend to require high energy consumption throughout the process. Therefore, there is a need for a separation technology that can reduce the amount of energy consumed in the process of separating gas from the gas phase.

[0005] Furthermore, gas separation processes using ion exchange resins do not necessarily provide sufficient separation performance, and further improvements in performance are required.

[0006] In terms of solving these problems, there is room for further improvement in the conventional techniques including those described in Patent Documents 1 to 6.

[0007] An object of the present invention is to provide a gas adsorption separation membrane that can reduce the amount of energy consumption required for a gas separation process and has excellent gas separation performance, and a method for producing the gas adsorption separation membrane. [Means for solving the problem]

[0008] As a result of investigations, the inventors have found that in order to reduce the energy consumption required for a gas separation process using an ion exchange resin, it is important to reduce the air resistance of the gas passed through the ion exchange resin, and that in order to improve the separation performance of a gas separation process using an ion exchange resin, it is important to ensure a high probability of contact between the ion exchange resin and the gas to be separated contained in the mixed gas (hereinafter referred to as the "gas to be separated"), and have completed the present invention. According to the present invention, the following gas adsorption separation membranes and the like are provided. 1. A gas adsorption separation membrane having a spirally wound impermeable sheet and an ion exchange resin fixed to one or both surfaces of the impermeable sheet. 2. The gas adsorption separation membrane according to 1, wherein the gas adsorption separation membrane further comprises a breathable spacer, and the impermeable sheet and the breathable spacer are superimposed and spirally wound. 3. The gas adsorption separation membrane according to 2, wherein the air-permeable spacer has a thickness of 0.1 to 2.0 mm. 4. The gas adsorption separation membrane according to any one of 1 to 3, which has a support member that supports the impermeable sheet. 5. The gas adsorption separation membrane according to any one of 1 to 4, wherein the ion exchange resin is an anion exchange resin. 6. A gas adsorption separation membrane according to any one of 1 to 5, which is used for separating carbon dioxide from a gas phase. 7. A method for producing a gas adsorption separation membrane, comprising: a fixing step of fixing an ion exchange resin to an impermeable sheet; and a winding step of spirally winding the impermeable sheet with the ion exchange resin fixed thereto. 8. The method for producing a gas adsorption separation membrane according to 7, wherein in the winding step, the impermeable sheet is overlapped with a breathable spacer and wound in a spiral shape. 9. The method for producing a gas adsorption separation membrane according to 7 or 8, further comprising the step of supporting the impermeable sheet with a support member after the winding step. 10. The method for producing a gas adsorption / separation membrane according to any one of 7 to 9, wherein an anion exchange resin is used as the ion exchange resin. 11. The method for producing a gas adsorption separation membrane according to any one of 7 to 10, wherein the gas adsorption separation membrane is used for separating carbon dioxide from a gas phase. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a gas adsorption separation membrane and a method for producing a gas adsorption separation membrane that can reduce the amount of energy consumption required for the gas separation process and has excellent gas separation performance. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a perspective view showing an example of a gas adsorption separation membrane of the present invention. [Figure 2] FIG. 2 is a view showing a cross section of the gas adsorption / separation membrane shown in FIG. 1, cut perpendicular to the gas flow direction. [Figure 3] FIG. 2 is a diagram illustrating the wound state of the impermeable sheet and the breathable spacer that constitute the gas adsorption separation membrane shown in FIG. [Figure 4]2 is an enlarged view showing a part of an impermeable sheet and a ventilation spacer that constitute the gas adsorption separation membrane shown in FIG. 1. FIG. [Figure 5] 1 is a diagram schematically illustrating a gas separation device equipped with a gas adsorption separation membrane according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] DETAILED DESCRIPTION OF THE INVENTION The following describes an embodiment of the invention. In this specification, "x to y" represents a numerical range of "not less than x and not more than y." The upper and lower limits of the numerical ranges can be combined in any way. Furthermore, among the individual embodiments of the aspects of the present invention described below, two or more embodiments that are not mutually contradictory can be combined, and an embodiment in which two or more embodiments are combined is also an embodiment of the aspects of the present invention.

[0012] [Gas adsorption separation membrane] A gas adsorption separation membrane according to one embodiment of the present invention comprises a spirally wound impermeable sheet and an ion exchange resin fixed to one or both surfaces of the impermeable sheet.

[0013] This reduces the energy consumption required for the gas separation process and provides excellent gas separation performance.

[0014] A gas adsorption separation membrane according to one embodiment of this aspect will be described below with reference to FIG. FIG. 1 is a perspective view showing an example of a gas adsorption separation membrane of the present invention, FIG. 2 is a diagram showing a cross section of the gas adsorption separation membrane shown in FIG. 1 cut perpendicular to the gas flow direction, FIG. 3 is a diagram for explaining the wound state of the impermeable sheet and breathable spacer that constitute the gas adsorption separation membrane shown in FIG. 1, and FIG. 4 is an enlarged diagram showing a portion of the impermeable sheet and breathable spacer that constitute the gas adsorption separation membrane shown in FIG. 1.

[0015] In FIG. 1, the gas adsorption separation membrane 100 has a support shaft 111 and an impermeable sheet 115 . The impermeable sheet 115 is spirally wound around the support shaft 111 (see FIGS. 2 and 3). Although the configuration shown in FIG. 1 includes a support shaft 111, the gas adsorption separation membrane of the present invention does not necessarily have to include the support shaft 111. Bead-like ion exchange resin 119 is fixed to both sides of impermeable sheet 115 (see FIG. 4). The ion exchange resin 119 is not limited to being fixed to both sides of the impermeable sheet 115, but may be fixed to only one side.

[0016] The ion exchange resin 119 may be fixed to the impermeable sheet 115 by an adhesive applied to the impermeable sheet 115 . The ion exchange resin 119 may be placed directly on the impermeable sheet 115 and fixed thereto by heat fusion.

[0017] The ion exchange resin 119 may be fixed to a partial area of ​​the impermeable sheet 115 or may be fixed to the entire area of ​​the impermeable sheet 115 .

[0018] It is preferable that the density of the ion exchange resin 119 on the surface of the impermeable sheet 115 is higher, which can improve the probability of contact between the gas passed through the gas adsorption separation membrane and the ion exchange resin 119. The density of the ion exchange resin 119 on the surface of the impermeable sheet 115 is 0.01 g / cm 2 More than 0.03g / cm 2 or more, or 0.05g / cm 2 It may be more than that. The upper limit of the density of the ion exchange resin 119 on the surface of the impermeable sheet 115 is not particularly limited, but from the viewpoint of convenience in manufacturing, it is set to, for example, 5 g / cm 2 or less than 3g / cm 2 It may be the following:

[0019] 1, a mixed gas 114 containing a gas to be separated is introduced through a gas inlet 112 of the gas adsorption separation membrane 100, passes through spaces between impermeable sheets 115, and is released through a gas outlet 113. During this process, the mixed gas 114 passing through the spaces between the impermeable sheets 115 comes into contact with an ion exchange resin 119 fixed to one or both surfaces of the impermeable sheets 115.

[0020] The gas to be separated contained in the mixed gas 114 that comes into contact with the surface of the ion exchange resin 119 is ionized on the surface of the ion exchange resin 119 (for example, if the gas to be separated is carbon dioxide, bicarbonate ions (HCO - ), which causes the target gas to be separated from the mixed gas 114. From the gas outlet 113 side of the gas adsorption / separation membrane 100, a gas 118 in which the concentration of the target gas to be separated has been reduced is released.

[0021] The mixed gas passed through the gas adsorption separation membrane according to this embodiment can move through the gaps between the spirally wound impermeable sheets. Therefore, the gas adsorption separation membrane according to this embodiment can reduce the airflow resistance when aerating the mixed gas 114 compared to a conventional gas separation unit (for example, reactor A in FIG. 1 of Patent Document 1), in which the mixed gas is passed through the gaps between beads of ion exchange resin packed in a resin tower. This reduces the power applied to the pump that transfers the mixed gas 114 toward the ion exchange resin, thereby reducing the energy consumption required for the gas separation process.

[0022] Furthermore, in conventional gas separation units (for example, reactor A in Figure 1 of Patent Document 1), among the bead-shaped ion exchange resins packed in the resin tower, only the ion exchange resins that form gaps through which the mixed gas passes can come into contact with the mixed gas. In contrast, in the gas adsorption separation membrane according to the present embodiment, the ion exchange resins 119 are dispersed and fixed on one or both surfaces of the impermeable sheet 115, and therefore the contact area of ​​the ion exchange resins 119 with the mixed gas 114 is increased, and the probability of contact between the ion exchange resins 119 and the mixed gas 114 can be improved, compared to when the mixed gas is passed through a conventional gas separation unit in which beads of ion exchange resin are packed in a resin tower. Therefore, a high proportion of the gas to be separated contained in the mixed gas can be adsorbed onto the surface of the ion exchange resins 119, resulting in excellent gas separation performance.

[0023] Furthermore, the gas adsorption / separation membrane according to this embodiment includes an impermeable sheet having an ion exchange resin fixed thereto, wound in a spiral shape, which increases the probability of contact between the ion exchange resin and the mixed gas while enabling the overall size of the gas adsorption / separation membrane to be made compact. Therefore, the gas adsorption / separation membrane according to this embodiment is easy to handle. Furthermore, an increase in the overall size of a gas separation device including the gas adsorption / separation membrane according to this embodiment can be suppressed.

[0024] An impermeable sheet is a sheet that does not allow gas to pass through. The impermeable sheet 115 may be made of an organic material that does not allow gas to pass through, such as a high-density polyethylene sheet or a high-density polypropylene sheet. The thickness of the impermeable sheet 115 is not particularly limited, and may be, for example, 0.05 to 1.0 mm, or 0.1 to 0.8 mm. By making the thickness of the impermeable sheet 115 0.05 mm or more, the sheet strength can be maintained and the sheet can be prevented from being damaged. Furthermore, by making the thickness of the impermeable sheet 115 1.0 mm or less, the sheet itself has an appropriate stiffness, which allows for smooth spiral wrapping. Furthermore, by making the thickness of the impermeable sheet 115 1.0 mm or less, the sheet itself has an appropriate thickness, which allows for a sufficient number of wraps of the sheet, and allows for a sufficient level of anion exchange resin filling rate in the gas adsorption separation membrane 100.

[0025] The type of ion exchange resin is not particularly limited as long as it is suitable for separating gases from a mixed gas. Examples of ion exchange resins include anion exchange resins and cation exchange resins. When the gas to be separated from the mixed gas is an acidic gas such as sulfur oxides (SOx) such as carbon dioxide, sulfur dioxide, and sulfur trioxide, or nitrogen oxides (NOx) such as nitrogen dioxide and nitric oxide, an anion exchange resin is preferably used. When the gas to be separated from the mixed gas is a basic gas such as ammonia, a cation exchange resin is preferably used.

[0026] The anion exchange resin may be a strongly basic anion exchange resin or a weakly basic anion exchange resin. Examples of strongly basic anion exchange resins include anion exchange resins having a quaternary amine with an ion exchange group such as a trimethylammonium group or a dimethylethanolammonium group. Examples of weakly basic anion exchange resins include anion exchange resins having a tertiary amine or primary amine, such as polyamine or dimethylamine, as an ion exchange group. Among these, it is preferable to use a strongly basic anion exchange resin, which exhibits a higher ion exchange capacity.

[0027] As the anion exchange resin, a commercially available product may be used, for example, anion exchange resins manufactured by Mitsubishi Chemical Corporation, DuPont, or Purolite Co., Ltd. may be used. As the anion exchange resin, for example, strongly basic anion exchange resins with the product names "A200", "A300", "A400", "A500", "A600", and "SGA550" (all manufactured by Purolite Co., Ltd.) can be used.

[0028] Examples of the cation exchange resin include cation exchange resins having a sulfonic acid group, a carboxylic acid group, or the like as an ion exchange group.

[0029] In one embodiment, the gas adsorption separation membrane may further include a breathable spacer. The gas adsorption separation membrane 100 according to the embodiment shown in Fig. 1 is configured such that an impermeable sheet 115 and a breathable spacer 116 are stacked and spirally wound around a support shaft 111 (see Figs. 2 and 3). According to this embodiment, the breathable spacers 116 form appropriate gaps between the spirally wound impermeable sheets 115. The mixed gas 114 passed through the gas adsorption separation membrane 100 can move through the gaps between the impermeable sheets 115 formed by the breathable spacers 116, thereby further reducing the ventilation resistance of the mixed gas 114.

[0030] There are no particular limitations on the ventilation spacer 116, as long as it is mesh-like, breathable, and can form ventilation gaps between the impermeable sheets 115 wound in a spiral shape. The material of the ventilation spacer 116 is not particularly limited, but examples thereof include synthetic fibers such as polyethylene and polypropylene, natural fibers such as cotton, hemp, paper and cellulose, and metals such as aluminum, stainless steel and titanium.

[0031] The thickness of the ventilation spacer 116 may be 0.1 to 2.0 mm, or may be 0.3 to 1.5 mm. By making the thickness of the ventilation spacer 116 0.1 mm or more, the ventilation spacer can be placed between the impermeable sheets 115 that are rolled and overlapped to provide an appropriate space, thereby reducing the ventilation resistance of the mixed gas 114. By setting the thickness of the ventilation spacer 116 to 2.0 mm or less, the probability of contact between the mixed gas 114 and the ion exchange resin can be maintained at a high level. The shape of the ventilation spacer is not particularly limited as long as it can secure a space between the impermeable sheets that are rolled and overlapped. The ventilation spacer can be in the form of a sheet like the impermeable sheets (see Figures 2 and 3), but it may also be in another shape, for example, a long shape with a smaller area than the impermeable sheets, or a strip shape. For example, the elongated ventilation spacer may be spirally wound around the support shaft 111 with the impermeable sheet 115 overlapping either or both of the gas inlet 112 end and the gas outlet 113 end. For example, a strip-shaped ventilation spacer can be attached and installed between the impermeable sheets 115 that are rolled and overlapped in either or both of the gas inlet 112 side end and the gas outlet 113 side end. Although the gas adsorption separation membrane 100 according to the embodiment shown in FIG. 1 is provided with a ventilation spacer, the ventilation spacer is not necessarily required in the gas adsorption separation membrane according to this embodiment if the gaps between the ion exchange resins are breathable.

[0032] In one embodiment, the gas adsorption separation membrane may have a support member that supports the impermeable sheet. The support member may be of any shape as long as it can support the spirally wound impermeable sheet so as to maintain the spiral shape, and there are no particular limitations on the shape of the support member. The support member 117 may support the impermeable sheet 115 by fixing the gas inlet end 112 and the gas outlet end 113 of the spirally wound impermeable sheet 115, for example, as shown in Figure 1. The support member is not limited to the form of support member 117 shown in FIG. 1, but may be one that houses a part or the whole of impermeable sheet 115 wound in a spiral shape and supports impermeable sheet 115. By supporting the impermeable sheet 115 with the support member 117, the impermeable sheet 115 can be stably maintained in a spirally wound state while the mixed gas 114 can be passed through the gas adsorption separation membrane 100, thereby achieving excellent gas separation performance.

[0033] 1 shows the configuration of gas adsorption separation membrane 100 including support member 117, but the gas adsorption separation membrane of the present invention does not necessarily have to include a support member. For example, impermeable sheet 115 may be spirally wound with one end fixed to support shaft 111, and the other end of impermeable sheet 115 may be attached to the surface of the wound impermeable sheet 115 with an adhesive or the like. In this case, even if impermeable sheet 115 is not supported by a support member, mixed gas 114 can be passed through gas adsorption separation membrane 100 while impermeable sheet 115 is stably maintained in a spirally wound state.

[0034] The gas adsorption separation membrane according to this embodiment can be used in a gas separation process for separating various gases from a gas phase (mixed gas).

[0035] A gas adsorption separation membrane according to one embodiment is used to separate carbon dioxide from a gas phase. An anion exchange resin can be suitably used as the ion exchange resin for the gas adsorption separation membrane according to this embodiment. The gas adsorption separation membrane according to this embodiment can reduce the energy consumption required for the entire separation process of separating carbon dioxide from a gas phase and can achieve excellent carbon dioxide separation performance. The carbon dioxide separated by the gas adsorption separation membrane according to this embodiment using the gas separation method described below may be stored underground, for example, by carbon dioxide capture and storage (CCS) technology, or may be converted into useful substances such as carbon monoxide and methane by CCU (Carbon Dioxide Capture and Utilization) and reused.

[0036] [Method for manufacturing gas adsorption separation membrane] A method for producing a gas adsorption separation membrane according to one embodiment of the present invention includes the following steps (1) and (2). (1) Fixing process of fixing ion exchange resin to an impermeable sheet (2) A winding process in which the impermeable sheet with the ion exchange resin fixed thereto is wound into a spiral shape.

[0037] The gas adsorption separation membrane according to the above-described embodiment of the present invention can be obtained by the method for producing a gas adsorption separation membrane according to the present embodiment. This reduces the amount of energy consumed in the gas separation process and provides a gas adsorption / separation membrane with excellent gas separation performance.

[0038] (Process (1)) First, ion exchange resin 119 is fixed to impermeable sheet 115 (see FIG. 4). The ion exchange resin 119 may be fixed to one surface of the impermeable sheet 115 or may be fixed to both surfaces of the impermeable sheet 119 .

[0039] In one embodiment, the ion exchange resin 119 is fixed to one or both surfaces of the impermeable sheet 115 by an adhesive. As the adhesive, a known adhesive suitable for adhering an ion exchange resin can be appropriately selected and used depending on the material of the impermeable sheet 115. This allows step (1) (fixing step) to be carried out simply and in a short time, and also allows the ion exchange resin 119 to be fixed to the impermeable sheet 115 reliably.

[0040] In one embodiment, the ion exchange resin 119 is fixed to one or all of the surfaces of the impermeable sheet 115 by heat sealing. The heating temperature during heat fusion can be appropriately selected depending on the material of the impermeable sheet 115. The heating temperature during heat fusion may be, for example, 120 to 400°C, or 150 to 300°C. This allows the ion exchange resin 119 to be firmly fixed to the surface of the impermeable sheet 115.

[0041] The ion exchange resin may be fixed to a partial area of ​​the impermeable sheet 115 or may be fixed to the entire area of ​​the impermeable sheet 115 .

[0042] The ion exchange resin is applied to the surface of the impermeable sheet 115 as follows: 0.01g / cm 2 More than 0.03g / cm 2 or more, or 0.05g / cm 2It may be fixed at a density of 5 g / cm or more. 2 or less than 3g / cm 2 The following densities may be used:

[0043] As the impermeable sheet 115, the sheet explained in the section on gas adsorption separation membranes can be used.

[0044] The ion exchange resin may be any of the ion exchange resins described above in the section on gas adsorption separation membranes, such as anion exchange resins and cation exchange resins. In one embodiment of the method for producing a gas adsorption / separation membrane, an anion exchange resin is used as the ion exchange resin, thereby obtaining a gas adsorption / separation membrane suitable for separating acidic gases such as sulfur oxides (SOx) such as carbon dioxide, sulfur dioxide, and sulfur trioxide, and nitrogen oxides (NOx) such as nitrogen dioxide and nitric oxide. In one embodiment of the method for producing a gas adsorption separation membrane, a cation exchange resin is used as the ion exchange resin, thereby obtaining a gas adsorption separation membrane suitable for separating basic gases such as ammonia.

[0045] (Process (2)) Next, the impermeable sheet 115 with the ion exchange resin fixed thereto is wound in a spiral shape. For example, one end of the impermeable sheet 115 may be fixed to the support shaft 111 and wound spirally around the support shaft 111.

[0046] In one embodiment, an impermeable sheet 115 is spirally wound with a breathable spacer 116 overlapping it (see FIGS. 2 and 3). As a result, the impermeable sheets 115 are spirally wound with the breathable spacers 116 sandwiched between the impermeable sheets 115, and the breathable spacers are disposed between the overlapping impermeable sheets 115 that are wound together, forming an appropriate space (gap). This can further reduce the ventilation resistance of the mixed gas that is passed through the finally obtained gas adsorption separation membrane 100. As the ventilation spacer 116, the sheet explained in the section on gas adsorption separation membranes can be used.

[0047] The method for producing a gas adsorption separation membrane according to this embodiment may further include a step of supporting impermeable sheet 115 with support member 117 after the winding step. As the support member 117, the support member explained in the section on the gas adsorption separation membrane can be used. By including a step of supporting the spirally wound impermeable sheet 115 with a support member 117, the impermeable sheet 115 can be stably maintained in a spirally wound state when the mixed gas 114 is passed through the finally obtained gas adsorption separation membrane, thereby further improving the gas separation performance.

[0048] In one embodiment, the impermeable sheet 115 is supported by the support member 117 by fixing the gas inlet end 112 and the gas outlet end 113 of the spirally wound impermeable sheet 115 with the support member 117. In one embodiment, the impermeable sheet 115 is supported by the support member 117 by storing a part or the whole of the spirally wound impermeable sheet 115 in the support member 117 .

[0049] The gas adsorption / separation membrane obtained by the method for producing a gas adsorption / separation membrane according to this embodiment can be used to separate various gases from a gas phase (mixed gas). The gas adsorption separation membrane obtained by the gas adsorption separation membrane production method according to this embodiment can be suitably used, for example, for separating carbon dioxide from a gas phase (mixed gas).

[0050] [Gas separation device] A gas separation device equipped with a gas adsorption separation membrane 100 according to one embodiment of the present invention will be described with reference to FIG.

[0051] FIG. 5 is a diagram schematically illustrating a gas separation device equipped with a gas adsorption separation membrane 100 according to one embodiment of the present invention. 5 includes a membrane container 33 housing a gas adsorption separation membrane 100 (see FIG. 1), a mixed gas supply pipe 37 for supplying a mixed gas containing the gas to be separated from a gas supply source (not shown) containing the gas to be separated to the membrane container 33, and a water vapor supply device 35 for supplying water vapor to the membrane container 33 via a water vapor gas supply pipe 38. Connected to the outlet side of the membrane container 33 are a treated gas outlet pipe 34 for discharging a treated gas in which the concentration of the gas to be separated has been reduced, and a separated gas outlet pipe 36 for discharging the gas to be separated desorbed from the surface of the ion exchange resin of the gas adsorption separation membrane 100 housed in the membrane container 33 (hereinafter simply referred to as the "ion exchange resin housed in the membrane container 33"). The membrane container 33 is connected to a pressure pump (not shown) that adjusts the pressure inside the membrane container 33 and the pressure in the region of the membrane container 33 near the separation target gas outlet pipe 36 . The gas separation device 301 may also be provided with pipes connecting the various components and a pump for pressure-feeding the gas, as appropriate.

[0052] 5 shows a configuration in which the gas adsorption separation membrane 100 (see FIG. 1) is housed in the membrane container 33, but the method of using the gas adsorption separation membrane according to this embodiment is not limited to this. For example, the gas adsorption separation membrane 100 may be used by being installed directly in the gas separation device 301 without being housed in a membrane container.

[0053] In one embodiment, a separation membrane 31 connected to the source of gas containing the gas to be separated by a mixed gas inlet conduit 32 may be provided between the membrane container 33 and the source of gas containing the gas to be separated. The separation membrane 31 is a membrane that selectively separates a target gas from a gas, and may be an inorganic membrane or an organic membrane.

[0054] The gas separation device 301 may include a moisture supply device (not shown) that supplies moisture to the ion exchange resin stored in the membrane container 33 to create a quasi-gas state around the ion exchange resin. The "quasi-gas state" will be described in detail later.

[0055] The water vapor supply device 35 may also function as a moisture supply device that supplies moisture to the ion exchange resin stored in the membrane container 33 to make the surrounding environment of the ion exchange resin a quasi-gas state. In this case, the gas separation device 301 does not need to be provided with a separate moisture supply device. This can simplify the overall configuration of the gas separation device 301.

[0056] [Gas separation method] A gas separation method using the gas separation device 301 shown in FIG. 5 will be described below.

[0057] The gas separation method using gas separation device 301 shown in FIG. 5 includes the following steps. (A) A separation step in which a mixed gas containing a gas to be separated is passed through a separation membrane to separate a concentrated gas in which the gas to be separated is concentrated. (B) an adsorption step in which the concentrated gas obtained in the separation step is brought into contact with an ion exchange resin to adsorb the target gas to be separated in the concentrated gas onto the ion exchange resin; (C) A desorption step in which water vapor is brought into contact with the ion exchange resin after the adsorption step to desorb the target gas from the ion exchange resin.

[0058] (Process (A)) First, a mixed gas containing a gas to be separated is passed through the separation membrane 31 via the mixed gas inlet conduit 32. The mixed gas that has passed through the separation membrane 31 is separated into a gas in which the gas to be separated is concentrated (enriched gas) and a gas in which the concentration of the gas to be separated is reduced.

[0059] Although step (A) is not an essential step, by bringing the gas in which the gas to be separated is concentrated into contact with the ion exchange resin stored in the membrane container 33 in the subsequent adsorption step (step (B)), the adsorption efficiency of the gas to be separated onto the ion exchange resin can be improved.

[0060] When the target gas to be separated is carbon dioxide, it is preferable to use a membrane capable of separating oxides such as sulfur oxides (SOx) and nitrogen oxides (NOx), which are contained in large amounts in exhaust gas, from carbon dioxide as the separation membrane 31. By removing these oxides from a gas containing sulfur oxides (SOx), nitrogen oxides (NOx), and other oxides, and then contacting the resulting gas with an increased carbon dioxide concentration with an ion exchange resin stored in the membrane container 33 in a subsequent adsorption step (step (B)), the carbon dioxide contained in the gas can be adsorbed onto the ion exchange resin preferentially over other components (sulfur oxides (SOx), nitrogen oxides (NOx), etc.). Furthermore, when the separation membrane 31 is made of a material that is easily degraded by sulfur oxides (SOx), nitrogen oxides (NOx), etc., it is preferable to remove them in advance using existing abatement equipment such as a scrubber before passing the mixed gas containing the target gas through the separation membrane 31.

[0061] (Process (B)) Next, the concentrated gas obtained in the separation step is supplied to the membrane container 33 through the mixed gas supply pipe 37 and brought into contact with the ion exchange resin contained in the membrane container 33 . The target gas contained in the concentrated gas that has come into contact with the surface of the ion exchange resin is ionized on the surface of the ion exchange resin and adsorbed onto the ion exchange resin. From the outlet side of the membrane container 33, the treated gas with a reduced concentration of the target gas is discharged through the treated gas outlet pipe 34.

[0062] The ion exchange resin subjected to the adsorption step is preferably in an ambient environment in a quasi-vapor state. In this specification, the expression "an ion exchange resin is in an "ambient environment in a quasi-gas phase state"" means that the ion exchange resin is placed in a gas phase, and that water is present in a total amount of 1 to 20 times the ion exchange capacity of the ion exchange resin on the surface of the ion exchange resin spheres or in one or both of the regions near the surface of the ion exchange resin spheres and inside the spheres (hereinafter sometimes simply referred to as "near the surface of the ion exchange resin spheres"). When the amount of water present near the surface of the ion exchange resin spheres is equal to or greater than one equivalent of the ion exchange capacity of the anion exchange resin, the surface of the ion exchange resin spheres tends to be wet, and the target gas that comes into contact with the surface of the ion exchange resin is easily ionized on the surface of the ion exchange resin and can be easily adsorbed as ionic components on the surface of the ion exchange resin. As a result, a high proportion of the target gas that comes into contact with the surface of the ion exchange resin can be adsorbed, resulting in excellent gas separation performance. Furthermore, by setting the amount of water present near the surface of the ion exchange resin spheres to 20 times the equivalent or less of the ion exchange capacity of the anion exchange resin, the concentrated gas supplied to the membrane container 33 can smoothly move to the water present near the surface of each ion exchange resin sphere, and a high proportion of the target gas to be separated is dissociated into ions, which can come into contact with and be adsorbed onto the ion exchange resin. Therefore, the target gas to be separated contained in the mixed gas can come into contact with the ion exchange resin and be adsorbed onto the ion exchange resin with a high probability.

[0063] There are no particular limitations on the method for creating a state in which water is present in the vicinity of the surfaces of the ion exchange resin spheres in an amount 1 to 20 times equivalent to the ion exchange capacity of the ion exchange resin. For example, before the adsorption step is started, moisture may be supplied to the ion exchange resin from a moisture supplying device (not shown) so that moisture in the above range is present near the surface of the ion exchange resin spheres. Alternatively, after the desorption step (step (C)) described below is completed, the processing conditions for the desorption step (step (C)) may be appropriately adjusted so that moisture in the above range is present near the surface of the ion exchange resin spheres before moving on to the next adsorption step (step (B)).

[0064] The ion exchange resin to be subjected to the adsorption step may have a volume ratio of water to the total volume of the ion exchange resin of 1.8 to 36% by volume. For example, if the exchange capacity of the resin is 1 eq / L, the volume fraction of water in the total volume of the ion exchange resin used in the adsorption process can be 1.8 volume % or more, so that the gas to be separated that comes into contact with the surface of the ion exchange resin can be easily ionized. For example, if the exchange capacity of the resin is 1 eq / L, the volumetric ratio of water to the total volume of the ion exchange resin is 36% or less, so that the aerated gas can easily move while coming into contact with the surface of the ion exchange resin, and there is a high probability that the gas to be separated contained in the concentrated gas will come into contact with the ion exchange resin.

[0065] The volume percentage of water relative to the total volume of the ion exchange resin may be 1.8% by volume or more, 2.7% by volume or more, or 3.6% by volume or more, and may be 36% by volume or less, 32.4% by volume or less, or 28.8% by volume or less.

[0066] The supply rate (space velocity) of the gas from the mixed gas supply pipe 37 to the membrane vessel 33 may be, for example, 3 / hour or more, or 5 / hour or more, and 50 / hour or less, or 30 / hour or less. By setting the gas supply rate from the mixed gas supply pipe 37 to the membrane container 33 within the above range, the gas to be separated can be adsorbed at a high rate onto the surface of the ion exchange resin stored in the membrane container 33 .

[0067] When the inside of the membrane container 33 is an enclosed space, the pressure (gauge pressure) inside the resin tower (enclosed space) 33 during the adsorption process may be, for example, 50 kPa or more, 100 kPa or more, or 200 kPa or more, and may be 700 kPa or less, 500 kPa or less, or 300 kPa or less. By setting the pressure within the resin tower (sealed space) 33 in the adsorption step within the above range, a high proportion of the gas to be separated can be adsorbed onto the surface of the ion exchange resin stored in the membrane container 33. The higher the pressure, the easier it is for the gas to be separated to dissolve in the water near the surface of the ion exchange resin, increasing the adsorption efficiency, so it is preferable to set the pressure as high as possible within a range that does not significantly increase the required power.

[0068] When the inside of the membrane container 33 is an enclosed space, the temperature inside the resin tower (enclosed space) 33 during the adsorption process may be, for example, 10°C or higher, 15°C or higher, or 20°C or higher, and may be 100°C or lower, 95°C or lower, or 90°C or lower. By setting the temperature inside the resin tower (sealed space) 33 in the adsorption step within the above range, the gas to be separated can be adsorbed onto the surface of the ion exchange resin stored in the membrane container 33 at a high rate.

[0069] (Process (C)) Next, water vapor is supplied from a water vapor supply device 35 through a water vapor gas supply pipe 38 to contact the ion exchange resin that has undergone the adsorption step. When the water vapor comes into contact with the ion exchange resin, the ions adsorbed on the surface of the ion exchange resin are desorbed from the surface of the ion exchange resin as the gas to be separated.

[0070] The temperature of the steam may be, for example, 80°C or more, 85°C or more, or 90°C or more, and may be 130°C or less, 120°C or less, or 110°C or less. When the temperature of the water vapor is 80° C. or higher, the gas to be separated can be smoothly desorbed from the surface of the ion exchange resin. By keeping the temperature of the steam at 130°C or less, the amount of energy required to carry out the desorption step can be kept low, making it possible to reduce the energy required for the entire separation process of the target gas. In addition, it is possible to prevent thermal degradation of the ion exchange resin.

[0071] The steam used may be steam generated in a waste heat recovery boiler that recovers waste heat from a power plant, a factory, etc., or steam extracted from a steam turbine. This reduces the amount of energy required to perform the desorption step, and the entire separation process of the target gas can be made low energy. For example, when the temperature of the steam is 100°C to 110°C, steam extracted from a waste heat recovery boiler or a steam turbine can be suitably used.

[0072] The supply rate (space velocity) of steam from the steam gas supply pipe 38 to the membrane vessel 33 may be, for example, 3 / hour or more, or 5 / hour or more, and may be 50 / hour or less, or 30 / hour or less. By setting the supply rate of water vapor to the membrane container 33 within the above range, the gas to be separated can be efficiently desorbed from the surface of the ion exchange resin stored in the membrane container 33 .

[0073] When water vapor is supplied to the ion exchange resin from the water vapor gas supply pipe 38, the water vapor supply conditions may be adjusted appropriately so that the volume ratio of water to the total volume of the ion exchange resin after the desorption step (step (C)) is 1.8 to 36 volume %. As a result, after the desorption step (step (C)) is completed, when the next adsorption step (step (B)) and desorption step (step (C)) are started, the ion exchange resin can be kept in a quasi-gas-phase environment without separately adjusting the moisture content of the ion exchange resin, thereby enabling the gas separation process to be carried out efficiently. For example, by adjusting at least one selected from the group consisting of the supply rate, supply temperature, and supply time of water vapor to the ion exchange resin, the volume fraction of water in the total volume of the ion exchange resin after the desorption step (step (C)) is completed can be adjusted to fall within the above range.

[0074] When the inside of the membrane container 33 is an airtight space, the pressure (gauge pressure) inside the resin tower (airtight space) 33 when water vapor is supplied through the water vapor gas supply pipe 38 may be, for example, -54 kPa or more, or -50 kPa or more, and may be 98 kPa or less, 50 kPa or less, or 10 kPa. By setting the pressure inside the resin tower (sealed space) 33 in the desorption step within the above range, it becomes easier to maintain the water vapor in a gaseous state, and the gas to be separated can be efficiently desorbed from the surface of the ion exchange resin.

[0075] Next, the gas to be separated is separated from the mixed gas of the gas to be separated and water vapor gas that has desorbed from the surface of the ion exchange resin, and is recovered as a high-concentration gas to be separated from the outlet side of the membrane container 33 through the gas to be separated outlet pipe 36. For example, the mixed gas of the gas to be separated and water vapor gas can be guided to the vicinity of the outlet of a membrane container 33 containing an ion exchange resin, and the mixed gas can be pressurized or cooled to condense the water vapor in the mixed gas into water, thereby separating the mixed gas from the mixed gas. For example, the pressure inside the membrane container 33 storing the ion exchange resin can be reduced (for example, -20 kPa to -80 kPa) and water vapor can be supplied, and the mixed gas of the gas to be separated and water vapor gas that has desorbed from the surface of the ion exchange resin can be guided near the outlet of the membrane container 33, and the pressure near the outlet can be returned to normal pressure, thereby condensing water from the mixed gas and separating the gas to be separated.

[0076] According to the gas separation method using the gas separation device equipped with the gas adsorption separation membrane of this embodiment as described above, the amount of energy consumed throughout the process is reduced and excellent gas separation performance is obtained.

[0077] The gas adsorption separation membrane and the method for producing a gas adsorption separation membrane according to the present embodiment described above are suitable for use in separating a predetermined gas from a gas phase such as the atmosphere or exhaust gas from factories such as thermal power plants and steelworks. [Industrial Applicability]

[0078] The gas adsorption separation membrane and the method for producing a gas adsorption separation membrane of the present invention are suitably used for separating a predetermined gas from a gas phase such as the atmosphere or exhaust gas from factories such as thermal power plants and steel mills, but are not limited thereto. [Explanation of symbols]

[0079] 100 Gas adsorption separation membrane 111 Spindle 112 Gas inlet 113 Gas outlet 114 Mixed Gases 115 Impermeable Sheet 116 Ventilated spacer (breathable sheet) 117 Support member 118 Gas with reduced concentration of the gas to be separated 301 Gas Separation Device 31 Separation membrane 32 Mixed gas inlet conduit 33 Membrane container 34 Processed gas outlet pipe 35 Steam supply device 36 Separation target gas outlet pipe 37 Mixed gas supply pipe 38 Steam gas supply pipe

Claims

1. an impermeable sheet wound in a spiral shape; and an ion exchange resin fixed to one or both surfaces of the impermeable sheet.

2. The gas adsorption separation membrane further has a ventilation spacer, 2. The gas adsorption separation membrane according to claim 1, wherein the impermeable sheet and the breathable spacer are superimposed and spirally wound.

3. 3. The gas adsorption separation membrane according to claim 2, wherein the thickness of the ventilation spacer is 0.1 to 2.0 mm.

4. The gas adsorption separation membrane according to any one of claims 1 to 3, further comprising a support member for supporting the impermeable sheet.

5. The gas adsorption separation membrane according to any one of claims 1 to 3, wherein the ion exchange resin is an anion exchange resin.

6. The gas adsorption separation membrane according to any one of claims 1 to 3, which is used for separating carbon dioxide from a gas phase.

7. a fixing step of fixing an ion exchange resin to an impermeable sheet; and a winding step of spirally winding the impermeable sheet to which the ion exchange resin has been fixed.

8. 8. The method for producing a gas adsorption separation membrane according to claim 7, wherein in the winding step, the impermeable sheet is overlapped with a breathable spacer and wound spirally.

9. 9. The method for producing a gas adsorption separation membrane according to claim 7, further comprising a step of supporting the impermeable sheet with a support member after the winding step.

10. The method for producing a gas adsorption / separation membrane according to claim 7 or 8, wherein an anion exchange resin is used as the ion exchange resin.

11. 9. The method for producing a gas adsorption separation membrane according to claim 7 or 8, wherein the gas adsorption separation membrane is used for separating carbon dioxide from a gas phase.

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