Adsorption unit, adsorption device, and carbon dioxide recovery system

Abstract

An adsorption unit (40) comprises: a heat exchanger (41) that has a plurality of heat transfer pipes (44) through which a heat medium flows, and that is disposed in an air flow path (AP) through which air flows; and an adsorption member (50) that has an adsorbent (60) which adsorbs carbon dioxide in the air. The adsorption member (50) has a plurality of adsorption parts (51), each of which is disposed between the adjacent heat transfer pipes (44). Each of the plurality of adsorption parts (51) has a plurality of holes (56) through which the air passes, and carries the adsorbent (60).

Description

Adsorption units, adsorption devices, and carbon dioxide capture systems

[0001] The present disclosure relates to adsorption units, adsorption devices, and carbon dioxide capture systems.

[0002] There is a system for capturing carbon dioxide from the air. The carbon dioxide capture system described in Patent Document 1 includes an adsorption plate carrying an adsorbent and a flow pipe for heating the adsorption plate. Carbon dioxide in the air is adsorbed by the adsorbent. A heating medium flowing through the flow pipe heats and regenerates the adsorbent on the adsorption plate. The carbon dioxide desorbed from the adsorbent is transported by a pump and stored.

[0003] Japanese Patent Application Laid-Open No. 2023-13169

[0004] If the carbon dioxide adsorption capacity and regeneration capacity of an adsorption unit having an adsorbent can be increased, the carbon dioxide recovery efficiency can be improved.

[0005] The present disclosure aims to improve the efficiency of carbon dioxide capture.

[0006] The first aspect relates to an adsorption unit. The adsorption unit (40) includes a heat exchanger (41) having a plurality of heat transfer tubes (44) through which a heat medium flows and disposed in an air flow path (AP) through which air flows, and an adsorption member (50) having an adsorbent (60) that adsorbs carbon dioxide in the air. The adsorption member (50) includes a plurality of adsorption sections (51) disposed between adjacent heat transfer tubes (44). Each of the plurality of adsorption sections (51) has a plurality of holes (56) through which air passes and supports the adsorbent (60).

[0007] In the first aspect, air in the air flow path (AP) passes through the holes (56) of the adsorption section (51), thereby enabling efficient adsorption of carbon dioxide in the air by the adsorbent (60) of the adsorption section (51). The adsorption section (51) is disposed between adjacent heat transfer tubes (44). This facilitates transfer of heat from the heat medium flowing through the heat transfer tubes (44) to the adsorption section (51). As a result, the adsorption section (51) can be efficiently regenerated.

[0008] In the second embodiment, a gap is formed between the heat transfer tube (44) and the adsorption section (51) in the first embodiment.

[0009] In the second aspect, the work of inserting the adsorption section (51) between adjacent heat transfer tubes (44) and the work of removing the adsorption section (51) from between adjacent heat transfer tubes (44) become easier.

[0010] In a third aspect, in the first or second aspect, the heat transfer tube is a flat tube (44).

[0011] In the third aspect, the adsorption portion (51) is arranged between adjacent flat tubes (44), which facilitates the transfer of heat from the heat medium to the adsorption portion (51).

[0012] In a fourth aspect, in the third aspect, the flat tube (44) has a pipe-side flat portion (P1) facing the adsorption portion (51). The adsorption portion (51) has an adsorption-side flat portion (P2) facing the pipe-side flat portion (P1).

[0013] In the fourth aspect, the pipe-side flat surface portion (P1) and the adsorption-side flat surface portion (P2) face each other, which facilitates the transfer of heat from the heat medium to the adsorption portion (51).

[0014] In a fifth aspect, in any one of the first to fourth aspects, the adsorption portion (51) has, as holes, a plurality of through holes (56) extending in a predetermined direction.

[0015] In the fifth aspect, the air flows through the through-holes (56), and carbon dioxide in the air is adsorbed by the adsorbent (60).

[0016] In a sixth aspect, in the fifth aspect, the plurality of through holes (56) extend in a direction intersecting with the first direction, which is the arrangement direction of the plurality of heat transfer tubes (44).

[0017] In the sixth aspect, the plurality of through holes (56) do not interfere with the heat transfer tubes (44), and therefore, the pressure loss in the through holes (56) can be reduced.

[0018] In a seventh aspect, in the sixth aspect, the through-hole (56) extends in a direction intersecting the first direction and the second direction, which is the axial direction of the heat transfer tube (44).

[0019] In the seventh aspect, the through-holes (56) extend in a direction intersecting the first direction and the second direction, thereby reducing the pressure loss that occurs when air passes through the adsorption unit.

[0020] In an eighth aspect, in any one of the first to seventh aspects, the heat exchanger (41) has header pipes (42, 43) to which ends of the plurality of heat transfer tubes (44) are connected.

[0021] In the eighth aspect, the heat transfer medium in the plurality of heat transfer tubes (44) can be joined at the header collecting pipe (42, 43), or the heat transfer medium in the header collecting pipe (42, 43) can be split into the plurality of heat transfer tubes (44).

[0022] In a ninth aspect, in any one of the first to eighth aspects, the adsorption member (50) has a connecting portion (55) that connects the plurality of adsorption portions (51).

[0023] In the ninth aspect, the plurality of adsorption sections (51) can be handled as a single unit, and therefore, the work of attaching, detaching or replacing the adsorption member (50) can be easily performed.

[0024] In a tenth aspect, in the ninth aspect, the adsorption member (50) has a plurality of grooves (58) formed between adjacent adsorption portions (51), and each of the plurality of heat transfer tubes (44) is fitted into each of the plurality of grooves (58).

[0025] In the tenth aspect, by fitting the heat transfer tubes (44) into the grooves (58) of the adsorption member (50), the adsorption member (50) can be easily attached, detached or replaced.

[0026] In an eleventh aspect, in the tenth aspect, the plurality of grooves (58) are formed in the lower part of the adsorption member (50). The heat exchanger (41) supports the adsorption member (50) from below.

[0027] In the eleventh aspect, the heat exchanger (41) functions as a support member for the adsorption member (50).

[0028] In a twelfth aspect, in any one of the first to eleventh aspects, the adsorption section (51) includes a substrate (B) that supports an adsorbent (60). The substrate (B) is made of a material having a thermal conductivity of 1 W / (m·K) or more.

[0029] In the twelfth aspect, the heat of the heat transfer tube (44) is easily transferred to the adsorbent (60) through the substrate (B), thereby increasing the regeneration capacity of the adsorption member (50).

[0030] In a thirteenth aspect, in the first aspect, the heat transfer tubes are flat tubes (44). The arrangement direction of the flat tubes (44) is defined as a first direction, the extension direction of the flat tubes (44) is defined as a second direction, and the direction perpendicular to the first and second directions is defined as a third direction. The adsorption member (50) has a connecting portion (55) connecting the plurality of adsorption portions (51). Each of the plurality of adsorption portions (51) extends in the third direction from one end, which is the connecting portion (55) side, to the other end.

[0031] In the thirteenth aspect, the adsorption member (50) can be attached to the heat exchanger (41) by inserting each of the plurality of adsorption sections (51) between adjacent pairs of adsorption sections (51). The adsorption member (50) can be removed from the heat exchanger (41) by pulling each of the plurality of adsorption sections (51) out from between adjacent pairs of adsorption sections (51).

[0032] In a fourteenth aspect, in the thirteenth aspect, the adsorption portions (51) have enlarged surfaces (81, 82) that increase the distance in the first direction between adjacent adsorption portions (51) from one end side to the other end side in the third direction.

[0033] In the fourteenth aspect, the formation of the enlarged surfaces (81, 82) on the suction portions (51) increases the distance between adjacent suction portions (51) in the first direction. This makes it easier to insert the suction portions (51) between adjacent flat tubes (44). This also makes it easier to pull out the suction portions (51) from between adjacent flat tubes (44).

[0034] A fifteenth aspect is an adsorption device including the adsorption unit (40) according to any one of the first to fourteenth aspects, and a casing (31) that forms the air flow path (AP).

[0035] In a sixteenth aspect, in the fifteenth aspect, the casing (31) is formed with an inlet (34) through which air flows into the air flow path (AP) and an outlet (35) through which air flows out of the air flow path (AP). The plurality of through holes (56) include inlet holes (56a) located on the inlet (34) side and through which air flows in, and outlet holes (56b) located on the outlet (35) side and through which air flows out.

[0036] In the sixteenth aspect, the air that has flowed into the air flow path (AP) from the inlet (34) of the casing (31) flows smoothly into the through-hole (56). The air that has flowed out from the through-hole (56) flows smoothly into the outlet (35) of the casing (31). As a result, the pressure loss in the air flow path (AP) can be reduced.

[0037] A seventeenth aspect is a carbon dioxide recovery system including the adsorption unit (40) of any one of the first to sixteenth aspects.

[0038] FIG. 1 is a diagram illustrating the overall configuration of a carbon dioxide capture system. FIG. 2 is a perspective view of an adsorption unit. Note that some of the through-holes are not shown in FIG. 2. FIG. 3 is an exploded perspective view of the adsorption unit. FIG. 4 is an enlarged perspective view of a main portion of the adsorption unit. FIG. 5 is a cross-sectional view taken along line VV in FIG. 2. FIG. 6 is an enlarged cross-sectional view of region A1 in FIG. 5. FIG. 7 is a diagram corresponding to FIG. 6 of an adsorption unit of Modified Example 1. FIG. 8 is a schematic configuration diagram of an adsorption unit of Modified Example 2. FIG. 9 is a schematic configuration diagram of an adsorption unit of Modified Example 3. FIG. 10 is a schematic configuration diagram of an adsorption unit of Modified Example 4. FIG. 11 is a schematic configuration diagram of an adsorption unit of Modified Example 5.

[0039] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Note that the present disclosure is not limited to the embodiments shown below, and various modifications are possible within the scope of the technical concept of the present disclosure. Since the drawings are intended to conceptually explain the present disclosure, dimensions, ratios, or numbers may be exaggerated or simplified as necessary to facilitate understanding.

[0040] (1) Overall Configuration An embodiment of the present disclosure is a carbon dioxide capture system (1). The carbon dioxide capture system (1) of this example captures carbon dioxide from the atmosphere, in other words, from the outdoor air. The carbon dioxide capture system (1) of this example constitutes a DAC (Direct Air Capture) system that separates and captures carbon dioxide directly from the atmosphere.

[0041] As shown in Fig. 1, the carbon dioxide capture system (1) includes a refrigeration cycle device (10), an adsorption device (30) having an adsorption member (50), a capture unit (20), and a controller (C). The refrigeration cycle device (10) is a heating device that heats the adsorption member (50). The capture unit (20) is a device that captures carbon dioxide desorbed from the adsorption member (50). The controller (C) controls each device of the carbon dioxide capture system (1).

[0042] (2) Refrigeration Cycle Device The refrigeration cycle device (10) includes a refrigerant circuit (11) that performs a refrigeration cycle and a first fan (12). The refrigerant circuit (11) is filled with refrigerant. The refrigerant circuit (11) includes a compressor (13), a first heat exchanger (41), an expansion valve (14), and a second heat exchanger (15). The compressor (13) compresses and discharges the refrigerant. The compressor (13) is configured to have a variable rotation speed. The first heat exchanger (41) constitutes a radiator (condenser). The first heat exchanger (41) is provided in the adsorption device (30). The first heat exchanger (41) exchanges heat between the refrigerant and the adsorption member (50) to heat the adsorption member (50). The expansion valve (14) constitutes a pressure reduction mechanism that reduces the pressure of the refrigerant. For example, the expansion valve (14) is configured as an electronic expansion valve with a variable opening. The second heat exchanger (15) is an air heat exchanger located outside the room. The first fan (12) is located near the second heat exchanger (15). The second heat exchanger (15) exchanges heat between the refrigerant and the outdoor air blown by the first fan (12).

[0043] (3) Adsorption Device The adsorption device (30) has a casing (31), an inlet duct (32), and an outlet duct (33).

[0044] The casing (31) is hollow and defines an air flow path (AP) therein through which air flows. The casing (31) has a first plate (31a) and a second plate (31b). The first plate (31a) and the second plate (31b) face each other. In this example, the first plate (31a) is located on the lower side of the casing (31), and the second plate (31b) is located on the upper side of the casing (31).

[0045] The casing (31) is formed with an inlet (34) through which outdoor air flows into the air flow path (AP) and an outlet (35) through which air in the air flow path (AP) flows out. The inlet (34) is formed in the first plate (31a). The outlet (35) is formed in the second plate (31b). The air flow path (AP) is formed from the inlet (34) to the outlet (35).

[0046] The inlet duct (32) is connected to the inlet (34). The inlet duct (32) connects the outdoor space with the inlet (34). A first damper (36) is provided inside the inlet duct (32). The first damper (36) is switchable between an open state (shown by a solid line in FIG. 1 ) in which the inlet (34), which is the inlet portion of the air flow path (AP), is opened, and a closed state (shown by a dashed line in FIG. 1 ) in which the inlet (34) is closed.

[0047] The outlet duct (33) is connected to the outlet (35). The outlet duct (33) connects the outlet (35) to the outdoor space. A second damper (37) is provided inside the outlet duct (33). The second damper (37) is switchable between an open state (shown by a solid line in FIG. 1 ) in which the outlet (35), which is the outlet portion of the air flow path (AP), is opened, and a closed state (shown by a dashed line in FIG. 1 ) in which the outlet (35) is closed.

[0048] The adsorption device (30) includes an adsorption unit (40) and a second fan (38). The adsorption unit (40) and the second fan (38) are arranged in the air flow path (AP). In this example, the second fan (38) is arranged downstream of the adsorption unit (40) in the air flow direction. The second fan (38) transports air in the air flow path (AP).

[0049] (3-1) Details of the Suction Unit The configuration of the suction unit (40) will be described in detail with reference to Figures 2 to 6. In the following description, terms such as "upper," "lower," "front," "rear," "right," and "left" are based on the directions indicated by the arrows in Figure 2. In this example, the direction of air flow in the air flow path (AP) corresponds to the vertical direction (up-down direction).

[0050] 2 and 3, the adsorption unit (40) includes a first heat exchanger (41) and an adsorption member (50). The adsorption unit (40) is configured by attaching the adsorption member (50) to the first heat exchanger (41).

[0051] (3-1-1) First Heat Exchanger The first heat exchanger (41) is arranged in the air flow path (AP) in the casing (31). The first heat exchanger (41) is supported on the casing (31) via stays (not shown). The first heat exchanger (41) includes a first header collecting pipe (42), a second header collecting pipe (43), and a plurality of flat tubes (44) arranged between the header collecting pipes (41, 42).

[0052] The first header collecting pipe (42) is located at the left end of the first heat exchanger (41). The second header collecting pipe (43) is located at the right end of the first heat exchanger (41). The first header collecting pipe (42) and the second header collecting pipe (43) are formed in a cylindrical shape extending in the front-rear direction. In this example, the first header collecting pipe (42) and the second header collecting pipe (43) are formed in a substantially rectangular shape when viewed in cross section in the cylindrical axis direction. Both ends of the first header collecting pipe (42) and the second header collecting pipe (43) in the longitudinal direction (front-rear direction) are closed.

[0053] The first header collecting pipe (42) is connected to a first pipe (45). A first header space (S1) is formed inside the first header collecting pipe (42). The first header space (S1) connects the interior of the first pipe (45) to the interiors of the flat pipes (44). The first header collecting pipe (42) of this example distributes, for example, liquid-containing refrigerant that has flowed out of the first pipe (45), to each of the flat pipes (44) through the first header space (S1).

[0054] The second header collecting pipe (43) is connected to the second pipe (46). A second header space (S2) is formed inside the second header collecting pipe (43). The second header space (S2) connects the interior of the second pipe (46) with the interiors of the flat pipes (44). The second header collecting pipe (43) of this example joins the gas-containing refrigerant that has flowed out of the flat pipes (44) in the second header space (S2). The refrigerant that has joined in the second header space (S2) flows out into the second pipe (46).

[0055] The flat tubes (44) are arranged between the first header collecting pipe (42) and the second header collecting pipe (43). The flat tubes (44) constitute heat transfer tubes through which the refrigerant flows. As shown in FIG. 3 , the flat tubes (44) are arranged in a first direction. In this example, the arrangement direction (first direction) of the flat tubes (44) corresponds to the front-rear direction. The flat tubes (44) extend in a second direction so as to span the first header collecting pipe (42) and the second header collecting pipe (43). The extension direction of the flat tubes (44), or the axial direction of the flat tubes (44), corresponds to the second direction. In this example, the axial direction of the flat tubes (44) corresponds to the left-right direction.

[0056] As shown in FIGS. 5 and 6 , the flat pipe (44) has a flat shape extending along the air flow direction in a cross-sectional view taken along the pipe axis. The surface of the flat pipe (44) includes a first arc-shaped portion (44a), a second arc-shaped portion (44b), a first flat portion (44c), and a second flat portion (44d). The first arc-shaped portion (44a) is located on the inflow side of the air flow. The second arc-shaped portion (44b) is located on the downstream side of the air flow. The first flat portion (44c) and the second flat portion (44d) form a pipe-side flat portion (P1). The pipe-side flat portion (P1) is formed in a planar shape extending in the direction of the air flow. The first flat portion (44c) is located on one side of the flat pipe (44) in the first direction (the front side in this example) and is formed between the first arc-shaped portion (44a) and the second arc-shaped portion (44b). The second flat portion (44d) is located on the other side (rear side in this example) of the flat pipe (44) in the first direction and is formed between the first arc portion (44a) and the second arc portion (44b). In a pair of adjacent flat pipes (44), the first flat portion (44c) of one of the pair of flat pipes (44) faces the second flat portion (44d) of the other of the pair of adjacent flat pipes (44).

[0057] A plurality of refrigerant flow paths (R) are formed inside the flat tubes (44). That is, the flat tubes (44) constitute flat multi-hole pipes having a plurality of refrigerant flow paths (R). The plurality of refrigerant flow paths (R) are arranged in the air flow direction (in the vertical direction in this example). Each refrigerant flow path (R) extends in the second direction across both longitudinal ends of the flat tubes (44). One end of each refrigerant flow path (R) communicates with the first header space (S1), and the other end of each refrigerant flow path (R) communicates with the second header space (S2).

[0058] (3-1-2) Adsorption Member The adsorption member (50) is a member for adsorbing carbon dioxide. The adsorption member (50) includes a base material (B) and an adsorbent (60) supported on the base material (B). In this example, the base material (B) is made of a ceramic material. The material constituting the base material (B) preferably has a thermal conductivity of 1 W / (m·K) or more.

[0059] As shown in Fig. 2, the adsorption member (50) is disposed between the first header collecting pipe (42) and the second header collecting pipe (43). The adsorption member (50) is provided over the entire region between the first header collecting pipe (42) and the second header collecting pipe (43).

[0060] As shown in Fig. 3, the adsorption unit (40) of this example includes a first adsorption member (50A) and a second adsorption member (50B) as the adsorption member (50). The first adsorption member (50A) and the second adsorption member (50B) are arranged adjacent to each other in the second direction. The first adsorption member (50A) is located to the left of the first heat exchanger (41), and the second adsorption member (50B) is located to the right of the first heat exchanger (41). In the following description, for convenience, the first adsorption member (50A) and the second adsorption member (50B) may be referred to as the adsorption member (50).

[0061] 4 and 5, the adsorption member (50) has a plurality of adsorption sections (51) and a plurality of connecting sections (55) connecting adjacent adsorption sections (51). The plurality of adsorption sections (51) includes a substrate (B) and an adsorbent (60). The plurality of connecting sections (55) are formed of the substrate (B).

[0062] The adsorption portions (51) are partially disposed between adjacent flat tubes (44). Each adsorption portion (51) is formed in the shape of a rectangular parallelepiped extending in the second direction along the flat tube (44). The adsorption portion (51) has an intermediate portion (52) overlapping the flat tube (44) in the first direction, a windward portion (53) continuing from the intermediate portion (52) to the upstream side of the air flow, and a windward portion (54) continuing from the intermediate portion (52) to the downstream side of the air flow.

[0063] The adsorption portion (51) has a third flat portion (51a) and a fourth flat portion (51b). The third flat portion (51a) and the fourth flat portion (51b) constitute an adsorption-side flat portion (P2) facing the pipe-side flat portion (P1). The third flat portion (51a) is located on one side of the adsorption portion (51) in the first direction (in this example, the front side), and the fourth flat portion (51b) is located on the other side of the adsorption portion (51) in the first direction (in this example, the rear side). The third flat portion (51a) of the adsorption portion (51) faces the second flat portion (44d) of the flat tube (44), and the fourth flat portion (51b) of the adsorption portion (51) faces the first flat portion (44c) of the flat tube (44). In this embodiment, the pipe-side flat portion (P1) and the adsorption-side flat portion (P2) are in surface contact with each other. Specifically, the third flat portion (51a) of the adsorption portion (51) is in surface contact with the second flat portion (44d) of the flat tube (44), and the fourth flat portion (51b) of the adsorption portion (51) is in surface contact with the first flat portion (44c) of the flat tube (44).

[0064] A plurality of through holes (56) are formed in the base material (B) of the adsorption portion (51). The through holes (56) are holes through which air passes. In this example, the through holes (56) extend in the air flow direction. In other words, the through holes (56) extend in a direction that intersects with the first direction and also intersects with the second direction. Strictly speaking, the through holes (56) extend in a direction that is perpendicular to the first direction and also perpendicular to the second direction.

[0065] The through-hole (56) includes an inlet hole (56a) and an outlet hole (56b). The inlet hole (56a) is formed in a first surface (50a) of the adsorption member (50) on the air inlet side. The outlet hole (56b) is formed in a second surface (50b) of the adsorption member (50) on the air outlet side. The inlet hole (56a) is located on the inlet (34) side of the casing (31), and the outlet hole (56b) is located on the outlet (35) side of the casing (31). The through-hole (56) extends from the inlet hole (56a) to the outlet hole (56b). In this example, the first surface (50a) forms the lower surface of the adsorption member (50), and the second surface (50b) forms the upper surface of the adsorption member (50).

[0066] As shown in Fig. 4, the through holes (56) are arranged in a lattice pattern. When viewed in a cross section in the air flow direction, the through holes (56) are formed in a rectangular shape (strictly speaking, a square shape). The plurality of through holes (56) are arranged across both ends of the longitudinal direction (second direction) of the adsorption portion (51). The plurality of through holes (56) are arranged across both ends of the width direction (first direction) of the adsorption portion (51).

[0067] The connecting portions (55) connect the adsorption portions (51) adjacent to each other in the first direction. The adsorption portions (51) and the connecting portions (55) are integrated together. This connection forms a rectangular plate-shaped base portion (57) on the downstream side (upper side) of the adsorption member (50) in the air direction. In other words, the base portion (57) is formed by alternating and continuing leeward portions (54) of the adsorption member (50) and the connecting portions (55). The connecting portions (55) in this example do not have a through-hole (56).

[0068] A plurality of grooves (58) are formed in the first surface (50a) of the adsorption member (50). The plurality of grooves (58) constitute spaces formed between adjacent adsorption portions (51). The plurality of grooves (58) are formed in the lower portion of the adsorption member (50). The grooves (58) extend across both ends of the adsorption member (50) in the second direction. When viewed from the second direction, the grooves (58) extend toward the downwind side. The grooves (58) constitute a space extending from the first surface (50a) of the adsorption member (50) to the connecting portion (55). This space is formed in the shape of a flattened rectangular parallelepiped extending in the second direction.

[0069] A flat tube (44) is fitted into each groove (58). In this example, the flat tube (44) is fitted into each groove (58) with substantially no gap. Therefore, as described above, the flat tube (44) and the adsorption member (50) are in surface contact with each other. The flat tube (44) is fitted into each groove (58) of the adsorption member (50), so that the adsorption member (50) is supported by the first heat exchanger (41).

[0070] As shown in Fig. 6, an adsorbent (60) is supported on the substrate (B) of the adsorption section (51). In this example, the adsorbent (60) is supported at least on the inner surfaces of the through-holes (56) of the substrate (B). The adsorbent (60) is formed of a liquid film.

[0071] The adsorbent (60) has the property of adsorbing carbon dioxide. Strictly speaking, the higher the temperature of the adsorbent (60), the easier it is for carbon dioxide to be desorbed, and the lower the temperature, the easier it is for carbon dioxide to be adsorbed. Here, "adsorption" includes not only the adsorption of carbon dioxide onto the surface of a solid or liquid, but also the absorption of carbon dioxide into the interior of a solid or liquid. Furthermore, "adsorption" includes not only physical adsorption but also chemical adsorption. The adsorbent (60) is formed of a liquid film.

[0072] (4) Recovery Unit As shown in FIG. 1 , the recovery unit (20) includes a recovery flow path (21), a tank (22), a pump (23), and an on-off valve (24). The inlet end of the recovery flow path (21) is connected to the casing (31). The inlet end of the recovery flow path (21) is connected to the air flow path (AP). The outlet end of the recovery flow path (21) is connected to the tank (22). The tank (22) stores the recovered carbon dioxide. The pump (23) reduces the pressure inside the casing (31) and transports the carbon dioxide desorbed from the adsorption member (50). The on-off valve (24) is provided in the recovery flow path (21) and opens and closes the recovery flow path (21). The recovery unit (20) may include a damper that opens and closes the recovery flow path (21) instead of the on-off valve (24).

[0073] (5) Controller As shown in Fig. 1, the controller (C) controls the refrigeration cycle apparatus (10), the adsorption device (30), and the recovery unit (20). Specifically, the controller (C) controls the open / close states of the first damper (36) and the second damper (37), the ON / OFF states of the first fan (12) and the second fan (38), the ON / OFF state of the compressor (13), the rotation speed of the compressor (13), the opening degree of the expansion valve (14), the ON / OFF state of the pump (23), and the open / close state of the on-off valve (24). The controller (C) may control the rotation speed of the first fan (12), the second fan (38), or the pump (23).

[0074] The controller (C) comprises a microcomputer and a memory device that stores software for operating the microcomputer.

[0075] (6) Operation of the Carbon Dioxide System The carbon dioxide capture system (1) performs an adsorption operation as a first operation and a regeneration operation as a second operation. The carbon dioxide capture system (1) alternately repeats the adsorption operation and the regeneration operation at predetermined time intervals.

[0076] (6-1) Adsorption Operation In the adsorption operation, the first damper (36) and the second damper (37) are in an open state (the state indicated by the solid line in FIG. 1), and the on-off valve (24) is in a closed state. The compressor (13), the first fan (12), and the pump (23) are stopped, and the second fan (38) is in an operating state. The refrigeration cycle apparatus (10) does not perform a refrigeration cycle.

[0077] When the second fan (38) is operated, outdoor air passes through the inlet duct (32) and the inlet (34) in this order, and flows through the air flow path (AP) in the casing (31). The air in the air flow path (AP) flows through the through-holes (56) of the adsorption member (50). At this time, carbon dioxide in the air is adsorbed by the adsorbent (60). The air that has flowed out of the through-holes (56) and passed through the adsorption unit (40) passes through the outlet (35) and the outlet duct (33) in this order, and is discharged to the outside of the room.

[0078] (6-2) Regeneration Operation In the regeneration operation, the first damper (36) and the second damper (37) are closed (as indicated by the dashed lines in FIG. 1 ), and the on-off valve (24) is opened. The compressor (13), the first fan (12), and the pump (23) are in operation, and the second fan (38) is stopped. The refrigeration cycle apparatus (10) performs a refrigeration cycle in which the first heat exchanger (41) functions as a radiator (condenser) and the second heat exchanger (15) functions as an evaporator.

[0079] In the refrigerant circuit (11), the compressor (13) compresses the refrigerant and discharges the compressed refrigerant. The refrigerant discharged from the compressor (13) flows through the first heat exchanger (41). Specifically, in the first heat exchanger (41), the refrigerant in the first header collecting pipe (42) is divided into the flat tubes (44). The heat of the refrigerant in each flat tube (44) is transferred to the adsorption section (51). As a result, carbon dioxide adsorbed in the adsorbent (60) is desorbed. The refrigerant that flows through the flat tubes (44) and condenses is joined in the second header collecting pipe (43) and then decompressed by the expansion valve (14). The decompressed refrigerant absorbs heat from the outdoor air in the second heat exchanger (15) and evaporates. The evaporated refrigerant is compressed again by the compressor (13).

[0080] When the pump (23) is operated, the pressure in the air flow path (AP) of the casing (31) is reduced. When carbon dioxide is desorbed from the adsorption member (50), the carbon dioxide concentration in the air in the air flow path (AP) increases. In this manner, the concentrated carbon dioxide flows through the recovery flow path (21) and is recovered in the tank (22).

[0081] In the regeneration operation, when an amine-based substance is used as the adsorbent (60), the refrigeration cycle apparatus (10) is configured to heat the adsorbing member (50) to a temperature in the range of 80° C. to 100° C. Specifically, in the regeneration operation, the controller (C) adjusts the temperature of the refrigerant in the first heat exchanger (41) by controlling the rotation speed of the compressor (13). At this time, the controller (C) may control the opening of the expansion valve (14).

[0082] (7) Features (7-1) The adsorption unit (40) has a plurality of heat transfer tubes (44) through which a refrigerant flows as a heat medium, and also includes a first heat exchanger (41) arranged in an air flow path (AP) through which air flows, and an adsorption member (50) having an adsorbent (60) that adsorbs carbon dioxide in the air. The adsorption member (50) has a plurality of adsorption sections (51) respectively arranged between adjacent heat transfer tubes (44), and each of the plurality of adsorption sections (51) has a plurality of holes (56) through which air passes and supports the adsorbent (60).

[0083] In this configuration, when air in the air flow path (AP) flows through the plurality of holes (56) of the adsorption section (51) during the adsorption operation, carbon dioxide in the air is adsorbed by the adsorbent (60). The contact efficiency between the air flowing through the plurality of holes (56) and the adsorbent (60) is increased, and therefore the carbon dioxide adsorption capacity of the adsorbent (60) can be increased.

[0084] In this configuration, during the regeneration operation, heat of the refrigerant in the heat transfer tube (44) is transferred to the adsorption section (51). At least a portion of the adsorption section (51) is disposed between adjacent heat transfer tubes (44), which facilitates the transfer of heat of the refrigerant to the adsorption section (51). As a result, the regeneration capacity of the adsorbent (60) can be increased.

[0085] As described above, the adsorption unit (40) can increase both the adsorption capacity and the regeneration capacity, thereby improving the efficiency of recovering carbon dioxide.

[0086] (7-2) The heat transfer tube (44) and the adsorption section (51) are in contact with each other. This reduces the thermal resistance between the heat transfer tube (44) and the adsorption section (51), making it easier for the heat of the heat transfer tube (44) to be transferred to the adsorption section (51). As a result, the regeneration capacity of the adsorbent (60) can be increased.

[0087] (7-3) The heat transfer tubes are flat tubes (44), which facilitates the transfer of heat from the refrigerant in the flat tubes (44) to the adsorption portions (51).

[0088] Since the pipe-side flat surface (P1) of the flat tube (44) and the adsorption-side flat surface (P2) of the adsorption portion (51) face each other, the heat of the refrigerant in the flat tube (44) is more easily transferred to the adsorption portion (51).

[0089] Furthermore, since the pipe-side flat portion (P1) and the adsorption-side flat portion (P2) are in surface contact with each other, the heat of the refrigerant in the flat tubes (44) is more easily transferred to the adsorption portion (51).

[0090] (7-4) The adsorption section (51) has a plurality of through-holes (56) extending in a predetermined direction as holes, thereby reducing the pressure loss when air passes through the adsorption section (51).

[0091] In particular, the through-holes (56) extend in a direction intersecting (strictly speaking, perpendicular to) the first direction in which the flat tubes (44) are arranged, which makes it possible to prevent interference between the through-holes (56) and the flat tubes (44), and further reduce the pressure loss when air passes through the adsorption portion (51).

[0092] The through-holes (56) extend in a direction intersecting (strictly speaking, perpendicular to) a second direction, which is the axial direction of the flat tubes (44), in addition to the first direction, thereby reducing pressure loss when air passes through the adsorption unit (40).

[0093] (7-5) The adsorption member (50) has a connecting portion (55) that connects the plurality of adsorption sections (51). This allows the plurality of adsorption sections (51) to be handled as a single unit, facilitating the installation, removal, or replacement of the adsorption member (50).

[0094] The adsorption member (50) has a plurality of grooves (58) formed between adjacent adsorption portions (51), and each of the heat transfer tubes (44) fits into a corresponding one of the grooves (58). Therefore, by fitting the heat transfer tubes (44) into each of the grooves (58) of the adsorption member (50), the adsorption member (50) can be easily attached, detached, or replaced.

[0095] The heat transfer tubes are flat tubes (44), and the grooves (58) are formed along the tube-side flat portions (P1) of the flat tubes (44). Therefore, the flat tubes (44) can be stably held in the grooves (58). As a result, rattling of the adsorption member (50) relative to the first heat exchanger (41) can be suppressed.

[0096] The plurality of grooves (58) are formed in the lower part of the adsorption member (50). The first heat exchanger (41) supports the adsorption member (50) from below. Since the first heat exchanger (41) functions as a support member for the adsorption member (50), the number of parts can be reduced.

[0097] (7-6) The adsorption device (30) includes an adsorption unit (40) and a casing (31) that forms an air flow path (AP). The casing (31) is formed with an inlet (34) through which air flows into the air flow path (AP) and an outlet (35) through which air flows out of the air flow path (AP). The plurality of through holes (56) include inlet holes (56a) located on the inlet (34) side and through which air flows in, and outlet holes (56b) located on the outlet (35) side and through which air flows out.

[0098] In this configuration, the air that flows into the air flow path (AP) from the inlet (34) of the casing (31) flows smoothly into the through-hole (56). The air that flows out from the through-hole (56) flows smoothly into the outlet (35) of the casing (31). As a result, the pressure loss in the air flow path (AP) can be reduced.

[0099] (7-7) In this embodiment, the base material (B) is made of a material having a thermal conductivity of 1 W / (m·K) or more. This facilitates the transfer of heat from the heat transfer tube (44) to the adsorbent (60) through the base material (B), thereby increasing the regeneration capacity of the adsorption member (50).

[0100] (8) Modifications The above embodiment may be modified as follows.

[0101] (8-1) Modification 1 As shown in FIG. 7 , in Modification 1, gaps (71, 72) are formed between the flat pipes (44) and the adsorption portions (51). In this example, the gaps (71, 72) are formed in a first direction, which is the arrangement direction of the flat pipes (44). The gaps (71, 72) are formed between the pipe-side flat portions (P1) of the flat pipes (44) and the adsorption-side flat portions (P2) of the adsorption portions (51). More specifically, the first gap (71) is formed between the first flat portion (44c) of the flat pipe (44) and the fourth flat portion (51b) of the adsorption portions (51). The second gap (72) is formed between the second flat portion (44d) of the flat pipe (44) and the third flat portion (51a) of the adsorption portions (51).

[0102] Forming the gaps (71, 72) in this manner facilitates the operation of inserting the adsorption portion (51) between adjacent flat tubes (44) and the operation of removing the adsorption portion (51) from between adjacent heat transfer tubes (44). Note that one of the first gap (71) and the second gap (72) may be eliminated, and the tube-side flat surface portion (P1) on one side of the flat tube (44) may be brought into contact with the adsorption-side flat surface portion (P2) of the adsorption portion (51).

[0103] (8-2) Modification 2 As shown in FIG. 8 , the adsorption unit (40) of Modification 2 does not have the connecting portion (55) of the above-described embodiment. An adsorption portion (51) is provided between each pair of adjacent flat tubes (44). The adsorption portion (51) is sandwiched between the flat tubes (44) on both sides thereof, and is thereby held between these flat tubes (44). In Modification 2, the adsorption portions (51) are completely separated from each other. In Modification 2, the adsorption portions (51) can be supported on the heat exchanger (41) without having the connecting portion (55).

[0104] (8-3) Modification 3 As shown in Fig. 9, in an adsorption unit (40) of Modification 3, the base material (B) of the adsorption member (50) that supports the adsorbent (60) is made of a fibrous material such as metal fiber or carbon fiber. In Modification 3, the pores inside the fibers of the base material (B) form holes through which air flows. The adsorption member (50) in the example of Fig. 9 does not have a connecting portion (55), but the adsorption member (50) may have a connecting portion (55) as in the embodiment.

[0105] (8-4) Modification 4 As shown in Fig. 10, the first heat exchanger (41) of the adsorption unit (40) of Modification 4 is basically the same as that of the above-described embodiment. The arrangement direction of the flat tubes (44) is defined as a first direction, the extension direction of the flat tubes (44) (pipe axis direction) is defined as a second direction, and the direction perpendicular to the first and second directions is defined as a third direction. The third direction corresponds to the width direction of the flat tubes (44) or the direction of air flow.

[0106] As described above, the adsorption portions (51) are inserted between adjacent flat tubes (44). The adsorption portions (51) extend in the third direction from one end, which is the connecting portion (55), toward the other end. The adsorption portions (51) are inserted between adjacent flat tubes (44), thereby attaching the adsorption member (50) to the first heat exchanger (41). The adsorption portions (51) are pulled out from between the adjacent flat tubes (44), thereby removing the adsorption member (50) from the first heat exchanger (41).

[0107] In the fourth modification, each suction portion (51) has a first enlarged surface (81) and a second enlarged surface (82) as enlarged surfaces. The first enlarged surface (81) and the second enlarged surface (82) are located at the other end of the suction portion (51). Specifically, in a cross-sectional view in the second direction, the suction portion (51) has an intermediate portion (52) overlapping the flat tube (44) in the first direction and a tip portion (59) extending from the intermediate portion (52) toward the other end in the third direction. The tip portion (59) extends further toward the other end in the third direction than the flat tube (44). The first enlarged surface (81) and the second enlarged surface (82) are formed at the tip portion (59) of each suction portion (51). The length of the intermediate portion (52) in the third direction is greater than the length of the tip portion (59) in the third direction.

[0108] The first expanded surface (81) is formed at one end of the suction portion (51) in the first direction, and the second expanded surface (82) is formed at the other end of the suction portion (51) in the first direction. The first expanded surface (81) and the second expanded surface (82) are located at corners of the suction portion (51). The first expanded surface (81), when viewed in a cross section in the second direction, forms an inclined surface that extends downward toward the other end in the third direction. The second expanded surface (82), when viewed in a cross section in the second direction, forms an inclined surface that extends upward toward the other end in the third direction.

[0109] The first expanded surface (81) and the second expanded surface (82) increase the distance in the first direction between adjacent suction portions (51) from one end side to the other end side in the third direction. Specifically, the distance in the first direction between adjacent intermediate portions (52) is defined as a first distance (G1), and the distance in the first direction between adjacent tip portions (59) is defined as a second distance (G2). The first distance (G1) is constant throughout the third direction. The first distance (G1) is substantially equal to the thickness of the flat tube (44). The second distance (G2) is larger than the first distance (G1). The second distance (G2) gradually increases toward the other end side in the third direction.

[0110] In this way, in the fourth modification, the distance between adjacent adsorption portions (51) is increased at the other end side in the third direction. This makes it easier to insert each adsorption portion (51) between adjacent flat tubes (44). This allows the worker to easily attach the adsorption member (50) to the first heat exchanger (41). In addition, this makes it easier to pull out each adsorption portion (51) from between adjacent flat tubes (44). This allows the worker to easily remove the adsorption member (50) from the first heat exchanger (41).

[0111] The intermediate portion (52) and the flat tubes (44) are substantially in contact with each other, which can promote heat transfer between the flat tubes (44) and the intermediate portion (52). In addition, the contact between the flat tubes (44) and the intermediate portion (52) makes it difficult for the adsorption member (50) to come off from the first heat exchanger (41).

[0112] The tip end portion (59) is located at a position that does not contact the flat tube (44) in the first place, and therefore, even if the first enlarged surface (81) or the second enlarged surface (82) is formed on the tip end portion (59), there is almost no effect on the heat transfer between the flat tube (44) and the intermediate portion (52).

[0113] In the fourth modification, the first thickness (D1) of the adsorption portion (51) in the first direction is greater than the second thickness (D2) of the flat tube (44) in the first direction, thereby improving the strength of the adsorption portion (51).

[0114] In the fourth modification, the thickness (D3) of the base (57) in the third direction is greater than the first thickness (D1) of the adsorption portion (51) in the first direction, thereby ensuring the strength of the base (57) for supporting the plurality of adsorption portions (51).

[0115] In the fourth modification, when viewed in cross section in the second direction, an arc portion is formed on the other end side of the flat pipe (44) in the third direction, so that the pitch on the other end side of the adjacent flat pipes (44) is widened, facilitating insertion and removal of the suction portion (51).

[0116] In the fourth modification, the adsorption portion (51) may be formed with only one of the first expanded surface (81) and the second expanded surface (82).

[0117] In the fourth modification, the first expanded surface (81) and the second expanded surface (82) may be formed from the tip portion (59) to the intermediate portion (52).

[0118] In the fourth modification, the first expanded surface (81) and the second expanded surface (82) do not necessarily have to be inclined. The first expanded surface (81) and the second expanded surface (82) may be stepped or arcuate.

[0119] (8-5) Modification 5 Modification 5 shown in FIG. 11 differs from Modification 4 in that the suction portion (51) does not have a first enlarged surface (81) or a second enlarged surface (82). In Modification 5, a first distance (G1) that is constant throughout the entire third direction is formed between adjacent suction portions (51). The first distance (G1) is substantially greater than the second thickness (D2) of the flat pipe (44). In other words, a small gap is formed between the flat pipe (44) and the suction portion (51). This makes it easier to insert and remove the suction portion (51) between adjacent flat pipes (44).

[0120] In the fifth modification, a coating film (83) made of grease or the like is formed in the gap between the flat tube (44) and the adsorption portion (51). The coating film (83) functions as a promoter that promotes heat transfer between the flat tube (44) and the adsorption portion (51). This ensures heat transfer between the flat tube (44) and the adsorption portion (51) while forming a gap between the flat tube (44) and the adsorption portion (51). The coating film (83) also functions as a lubricant that reduces frictional resistance between the flat tube (44) and the adsorption portion (51). This makes it easier to insert and remove the adsorption portion (51) between adjacent flat tubes (44).

[0121] In the fifth modification, an elastic or flexible resin material may be provided in the gap between the flat tube (44) and the adsorption portion (51). This makes it easier to insert or remove the adsorption portion (51) between the adjacent flat tubes (44), and the resin material functions as a buffer material.

[0122] (9) Other Embodiments The above embodiment may have the following configurations.

[0123] The carbon dioxide capture system (1) does not have to be a DAC system that directly captures carbon dioxide from the atmosphere. For example, the carbon dioxide capture system (1) may capture carbon dioxide from a mixture of air and industrial exhaust gases.

[0124] The heating device may be an electric heater or a heat source that utilizes exhaust heat. The heating device may also be a hot water supply device that supplies high-temperature water as a heat medium to the heat transfer tubes (flat tubes (44)) of the adsorption unit (40).

[0125] The pressure reducing mechanism may be a capillary tube or a temperature-sensitive expansion valve.

[0126] The adsorbing member (50) may adsorb carbon dioxide in the room air instead of the outdoor air. The adsorbing member (50) may be applied to, for example, a ventilation system for ventilating a room.

[0127] The adsorbent (60) may be supported over the entire substrate (B).

[0128] The material of the substrate (B) of the adsorption member (50) that supports the adsorbent (60) may be metal. The substrate (B) may be made of a porous material. In this case, the pores inside the porous material form the holes through which air flows.

[0129] When an amine-based substance is used as the adsorbent (60), the adsorbent may be supported by coating the surface of a substrate made of a metal material with silica gel, polymer, or the like that functions as a functional group.

[0130] The second fan (38) may be disposed inside the inlet duct (32) or the outlet duct (33). The second fan (38) may be disposed upstream of the adsorption unit (40) in the air flow path (AP).

[0131] The first heat exchanger (41) may have a configuration in which a plurality of heat transfer tubes are arranged between two end plates without including a header pipe. In this case, the plurality of heat transfer tubes are connected by U-shaped tubes arranged on the outer sides of the end plates. The first heat exchanger may have a device for dividing the refrigerant into the plurality of heat transfer tubes and a device for combining the refrigerants from the plurality of heat transfer tubes.

[0132] The heat transfer tubes of the first heat exchanger (41) do not have to be flat tubes (44) but may be circular tubes. The flat tubes (44) may have only one hole.

[0133] The adsorption member (50) is composed of divided bodies, a first adsorption member (50A) and a second adsorption member (50B). However, the adsorption member (50) may be composed of a single member or three or more divided bodies. The divided bodies may be arranged in a second direction instead of the first direction.

[0134] The first heat exchanger (41) in this embodiment is arranged such that the first direction, which is the arrangement direction of the heat transfer tubes (44), is oriented horizontally. However, the first heat exchanger (41) may be arranged such that the first direction, which is the arrangement direction of the heat transfer tubes (44), is oriented vertically, or may be oriented in a direction oblique to the vertical and horizontal directions.

[0135] The entire adsorption portion (51) may be located between the adjacent flat tubes (44).

[0136] The plurality of through holes (56) may be holes extending in, for example, the second direction. That is, the through holes (56) preferably extend in a direction intersecting (strictly speaking, perpendicular to) the first direction in which the flat tubes (44) are arranged.

[0137] The connecting portion (55) may support the adsorbent (60). A plurality of through-holes (56) may be formed in the connecting portion (55), and the adsorbent (60) may be supported inside the through-holes (56).

[0138] Although the embodiments and modifications have been described above, it will be understood that various modifications in form and details are possible without departing from the spirit and scope of the claims. Furthermore, the above embodiments, modifications, and other embodiments may be combined or substituted as appropriate as long as the functionality of the subject matter of the present disclosure is not impaired.

[0139] The above-mentioned descriptions such as "first," "second," "third," etc. are used to distinguish the words to which these descriptions are attached, and do not limit the number or order of the words.

[0140] As described above, the present disclosure is useful for adsorption units, adsorption devices, and carbon dioxide capture systems.

[0141] 1 Carbon dioxide capture system 30 Adsorption device 31 Casing 34 Inlet 35 Outlet 40 Adsorption unit 41 First heat exchanger (heat exchanger) 44 Flat tube (heat transfer tube) 50 Adsorption member 51 Adsorption section 55 Connection section 56 Through hole (hole) 56a Inlet hole 56b Outlet hole 58 Groove 60 Adsorbent AP Air flow path P1 Tube side flat section P2 Adsorption side flat section

Claims

1. An adsorption unit comprising: a heat exchanger (41) having a plurality of heat transfer tubes (44) through which a heat medium flows, and arranged in an air flow path (AP) through which air flows; and an adsorption member (50) having an adsorbent (60) that adsorbs carbon dioxide in the air, wherein the adsorption member (50) has a plurality of adsorption sections (51) respectively arranged between adjacent heat transfer tubes (44), each of the plurality of adsorption sections (51) having a plurality of holes (56) through which air passes, and supporting the adsorbent (60).

2. The adsorption unit according to claim 1, wherein a gap is formed between the heat transfer tube (44) and the adsorption portion (51).

3. The adsorption unit according to claim 1 or 2, wherein the heat transfer tube is a flat tube (44).

4. The adsorption unit according to claim 3, wherein the flat tube (44) has a pipe-side flat portion (P1) facing the adsorption portion (51), and the adsorption portion (51) has an adsorption-side flat portion (P2) facing the pipe-side flat portion (P1).

5. The suction unit according to any one of claims 1 to 4, wherein the suction portion (51) has a plurality of through holes (56) extending in a predetermined direction as the holes.

6. The adsorption unit according to claim 5, wherein the plurality of through holes (56) extend in a direction intersecting a first direction which is an arrangement direction of the plurality of heat transfer tubes (44).

7. The adsorption unit according to claim 6, wherein the plurality of through holes (56) extend in a direction intersecting the first direction and a second direction which is an axial direction of the heat transfer tube (44).

8. The adsorption unit according to any one of claims 1 to 7, wherein the heat exchanger (41) has a header pipe (42, 43) to which ends of the plurality of heat transfer tubes (44) are connected.

9. The adsorption unit according to any one of claims 1 to 8, wherein the adsorption member (50) has a connecting portion (55) that connects a plurality of adsorption portions (51).

10. The adsorption unit according to claim 9, wherein the adsorption member (50) has a plurality of grooves (58) formed between the adjacent adsorption portions (51), and each of the plurality of heat transfer tubes (44) fits into each of the plurality of grooves (58).

11. The adsorption unit according to claim 10, wherein the plurality of grooves (58) are formed in a lower portion of the adsorption member (50), and the heat exchanger (41) supports the adsorption member (50) from below.

12. The adsorption unit according to any one of claims 1 to 11, wherein the adsorption portion (51) includes a base material (B) that supports the adsorbent (60), and the base material (B) is made of a material having a thermal conductivity of 1 [W / (m·K)] or more.

13. The adsorption unit according to any one of claims 1 to 11, wherein the heat transfer tubes are flat tubes (44), the arrangement direction of the flat tubes (44) is defined as a first direction, the extension direction of the flat tubes (44) is defined as a second direction, and a direction perpendicular to the first direction and the second direction is defined as a third direction, the adsorption member (50) has a connecting portion (55) connecting the plurality of adsorption portions (51), and each of the plurality of adsorption portions (51) extends in the third direction from one end side which is the connecting portion (55) side to the other end side.

14. The suction unit according to claim 13, wherein the suction portions (51) have enlarged surfaces (81, 82) that increase the distance in the first direction between adjacent suction portions (51) as they move from one end side to the other end side in the third direction.

15. An adsorption device comprising: an adsorption unit (40) according to any one of claims 1 to 14; and a casing (31) forming the air flow path (AP).

16. An adsorption device as described in claim 15, wherein the casing (31) is formed with an inlet (34) for allowing air to flow into the air flow path (AP) and an outlet (35) for allowing air to flow out of the air flow path (AP), and the plurality of through holes (56) include an inlet hole (56a) located on the inlet (34) side through which air flows in, and an outlet hole (56b) located on the outlet (35) side through which air flows out.

17. A carbon dioxide capture system comprising an adsorption unit (40) according to any one of claims 1 to 16.

Images