Gas recovery device

Abstract

A gas recovery device according to the present disclosure comprises a separation part that separates a target gas from a plurality of adsorption members adsorbing the target gas. The separation part has a separation container capable of accommodating the plurality of adsorption members. Each of the plurality of adsorption members has an outer peripheral part and a ventilation part having a system impedance lower than that of the outer peripheral part. In the separation container, the plurality of adsorption members are arranged such that the ventilation parts face each other.

Description

Gas recovery device

[0001] This disclosure relates to a gas recovery device. This application claims priority based on Japanese Patent Application No. 2024-160715 filed in Japan on September 18, 2024, the content of which is incorporated herein by reference.

[0002] In recent years, a DAC (Direct Air Capture) system that adsorbs carbon dioxide at a low concentration (e.g., about 410 ppm) in the atmosphere onto an adsorbent to recover carbon dioxide has attracted attention. In such a DAC system, after carbon dioxide is adsorbed onto the adsorbent, the carbon dioxide is separated from the adsorbent.

[0003] Further, Patent Document 1 below discloses an apparatus that provides a moving bed of an adsorbent that adsorbs harmful components in a gas flow path containing harmful components, and adsorbs the harmful components in the gas while moving the adsorbent on the moving bed.

[0004] Japanese Patent Application Laid-Open No. 11-169646

[0005] In the DAC system, since carbon dioxide is recovered from the atmosphere with a low carbon dioxide concentration, the recovery efficiency of carbon dioxide by the adsorbent is low, and the carbon dioxide recovery cost is high. In order to improve the recovery efficiency of carbon dioxide, it has been required to reduce the separation energy when separating carbon dioxide from the adsorbent.

[0006] In view of the above circumstances, an object of the present disclosure is to provide a gas recovery device capable of reducing the separation energy when separating a target gas from an adsorbent member.

[0007] The gas recovery device according to the present disclosure includes a separation unit that separates a target gas from a plurality of adsorbent members that have adsorbed the target gas. The separation unit has a separation container that can accommodate the plurality of adsorbent members. Each of the plurality of adsorbent members has an outer peripheral portion and a ventilation portion with a lower ventilation resistance than the outer peripheral portion. In the separation container, the plurality of adsorbent members are arranged such that the ventilation portions face each other.

[0008] According to the present disclosure, it is possible to provide a gas recovery device capable of reducing the separation energy when separating a target gas from an adsorbent member.

[0009] This is a block diagram of the gas recovery device according to Embodiment 1. This is a perspective view of the adsorption member according to Embodiment 1. This is an exploded perspective view of the adsorption member according to Embodiment 1. This is a schematic diagram of the air blower and adsorption unit according to Embodiment 1. This is a schematic diagram of the separation unit and heat supply unit according to Embodiment 1. This is a block diagram of the gas recovery device according to Embodiment 2. This is a schematic diagram of the separation unit and pressure fluctuation device according to Embodiment 2. This is a schematic diagram of the separation unit, heat supply unit and pressure fluctuation device according to Embodiment 3. This is a schematic diagram of the air blower and adsorption unit according to a modified example of Embodiment 1. This is a schematic diagram of the separation unit and heat supply unit according to a modified example of Embodiment 1. This is a perspective view of the adsorption member according to a modified example of Embodiment 1.

[0010] Embodiments of this disclosure will be described below with reference to the drawings. However, the scope of this disclosure is not limited to the embodiments described below and can be modified at will within the scope of the technical idea of ​​this disclosure.

[0011] Embodiment 1. Figure 1 is a block diagram of a gas recovery device 1 according to Embodiment 1. The gas recovery device 1 recovers carbon dioxide (target gas) from air (a mixed gas containing the target gas). The gas recovery device 1 is installed, for example, on the roof of a building (for example, a building or apartment building). However, the installation location of the gas recovery device 1 is not limited to this. The gas recovery device 1 may be installed in an open space next to a building, in the courtyard of an apartment building, in a desert, etc. The gas recovery device 1 may also be installed indoors.

[0012] The gas recovery device 1 comprises a blower unit 20, an adsorption unit 30, a separation unit 40, a heat supply unit 50, and a storage unit 60. The adsorption unit 30 uses the airflow from the blower unit 20 to adsorb carbon dioxide contained in the air with an adsorption member 10. The adsorption member 10 that has adsorbed carbon dioxide in the adsorption unit 30 is transported to the separation unit 40. The separation unit 40 separates carbon dioxide from the adsorption member 10 that has adsorbed carbon dioxide. The heat supply unit 50 supplies heat to the separation unit 40 to be used for the separation of carbon dioxide. The carbon dioxide separated from the adsorption member 10 in the separation unit 40 is stored in the storage unit 60. The adsorption member 10 from which carbon dioxide has been separated in the separation unit 40 is transported to the adsorption unit 30 and reused for carbon dioxide adsorption in the adsorption unit 30. The transport of the suction member 10 between the suction unit 30 and the separation unit 40 may be performed by an operator, or by a transport means such as a robotic arm or belt conveyor that operates according to a program.

[0013] As shown in Figure 2, the adsorption member 10 has a cylindrical shape. In the following description, the direction along the central axis of the adsorption member 10 will be referred to as the axial direction of the adsorption member 10. The adsorption member 10 has an outer circumference 10a and a ventilation portion 10b which has lower airflow resistance than the outer circumference 10a. Air flows through the adsorption member 10 in the axial direction. The length of the adsorption member 10 in the axial direction (i.e., the direction in which the airflow flows through the adsorption member 10) is smaller than the outer diameter of the ventilation portion 10b.

[0014] The adsorption member 10 includes a plurality of adsorbents 11 and a container 12 that houses the plurality of adsorbents 11. The container 12 includes a protective material 13 (first member) and two breathable members 14 (second member).

[0015] The adsorbent 11 contains a material capable of adsorbing carbon dioxide. Examples of materials capable of adsorbing carbon dioxide include amines, zeolites, silica gel, diatomaceous earth, alumina, and activated carbon. Multiple materials may be selected from the above, or materials other than those listed above may be used. The adsorbent 11 is made of a porous material. The adsorbent 11 has a spherical (bead) or cylindrical (pellet) shape. The shape of the adsorbent 11 is not limited to these, and it may also be in the form of a powder, for example.

[0016] As shown in Figures 2 and 3, the protective material 13 has a cylindrical shape with openings at both ends. The protective material 13 forms the outer circumference 10a of the suction member 10. The axial length of the protective material 13 is smaller than the diameter of the protective material 13.

[0017] The breathable member 14 is a circular member. The breathable member 14 is breathable. Two breathable members 14 are provided at both ends of the protective material 13. The breathable members 14 are provided to close the openings of the protective material 13. The breathable members 14 form the ventilation portion 10b of the adsorption member 10. Multiple openings are formed in the breathable member 14. The breathable member 14 is, for example, mesh-like. Note that the openings formed in the breathable member 14 are smaller than the adsorption member 11 in order to prevent the adsorbent 11 from falling off.

[0018] An annular locking projection 13a is formed on the inner circumferential surface of one end of the protective material 13. One of the breathable members 14 is locked to the locking projection 13a of the protective material 13. The suction member 10 also has an annular fixing cover 15 for fixing the other breathable member 14 to the other end of the protective material 13. The fixing cover 15 is fitted to the other end of the protective material 13 with the other breathable member 14 sandwiched between them. Alternatively, the breathable member 14 may be bonded to the other end of the protective material 13 without the fixing cover 15. Alternatively, the breathable member 14 and the protective material 13 may be formed integrally without the fixing cover 15.

[0019] The adsorption member 10 has a partition plate 16 that is placed inside the container 12. The partition plate 16 is composed of a plurality of partition pieces 16a that extend radially from the central axis of the protective material 13. The partition plate 16 (the plurality of partition pieces 16a) divides the internal space of the container 12 into a plurality of small spaces s. Each of the plurality of small spaces s is filled with a plurality of adsorbents 11. The shape of the partition plate 16 is not limited to this, and for example, the plurality of partition pieces 16a may be arranged in a grid or spiral shape.

[0020] The air blower unit 20 has a fan 21 that forms an airflow. As shown in Figure 4, the air blower unit 20 has an air intake 22 through which air is drawn in from the outside by the drive of the fan 21, and an air outlet 23 through which air is discharged to the outside. The air blower unit 20 is, for example, an outdoor unit or indoor unit of an air conditioning system, or a ventilation fan.

[0021] The suction part 30 is installed facing the blower part 20. The suction part 30 is configured to hold the suction member 10 at a position where it receives the airflow generated by the fan 21 of the blower part 20. In the following description, the vertical direction is referred to as the Z direction. In addition, in the suction part 30, one direction perpendicular to the Z direction is referred to as the X1 direction (second direction), and the direction perpendicular to both the X1 direction and the Z direction is referred to as the Y1 direction. The suction part 30 and the blower part 20 face each other in the X1 direction.

[0022] The adsorption unit 30 has an adsorption container 31 that can accommodate a plurality of adsorption members 10 and is breathable. The adsorption container 31 is a box-shaped container. The adsorption container 31 has a first side surface 32 and a second side surface 33 that face each other in the X1 direction. The first side surface 32 is provided with a plurality of first openings 32a that serve as air inlets. The second side surface 33 is provided with a plurality of second openings 33a that serve as air outlets. The second side surface 33 faces the air intake 22 of the blower unit 20 in the X1 direction. When the fan 21 of the blower unit 20 is driven, air flows through the adsorption container 31 in the X1 direction from the first openings 32a to the second openings 33a. That is, the X1 direction is the direction in which air flows within the adsorption container 31. The adsorption container 31 may also be arranged so that the first side surface 32 faces the air outlet 23 of the blower unit 20 in the X1 direction.

[0023] An adsorption section arrangement region A1 is formed inside the adsorption container 31, where a plurality of adsorption members 10 are arranged. In the adsorption section arrangement region A1, the plurality of adsorption members 10 are arranged in a direction perpendicular to the X1 direction. That is, in the adsorption section arrangement region A1, the plurality of adsorption members 10 are arranged in parallel with respect to the X1 direction. Note that at least the first adsorption member 10A and the second adsorption member 10B of the plurality of adsorption members 10 are arranged in a direction perpendicular to the X1 direction. In the illustrated example, in the adsorption section arrangement region A1, the plurality of adsorption members 10 are arranged in the Z direction. In the adsorption section arrangement region A1, the plurality of adsorption members 10 may be arranged in the Y1 direction. Also, in the adsorption section arrangement region A1, the adsorption members 10 are arranged so that the ventilation portion 10b faces the X1 direction. That is, in the adsorption section arrangement region A1, the adsorption members 10 are arranged so that the axial direction of the adsorption members 10 coincides with the X1 direction.

[0024] In the adsorption section 30, the length of the adsorption section arrangement area A1 in the X1 direction is shorter than the length of the adsorption section arrangement area A1 in the direction perpendicular to the X1 direction (in the illustrated example, the Z direction, i.e., the direction in which the multiple adsorption members 10 are lined up). In other words, in the adsorption container 31, the length of the first side surface 32 and the second side surface 33 in the X1 direction is shorter than the length of the first side surface 32 or the second side surface 33 in the direction perpendicular to the X1 direction (in the illustrated example, the Z direction).

[0025] The adsorption member 10 housed in the adsorption container 31 is exposed to the airflow generated by the fan 21 of the air blower 20. This causes air to enter the adsorption member 10 and air to be expelled from within the adsorption member 10. The adsorption unit 30 brings the airflow generated by the fan 21 into contact with the adsorption member 10 (adsorbent 11), causing carbon dioxide to be adsorbed onto the adsorption member 10 (adsorbent 11).

[0026] The heat supply unit 50 supplies heat to the separation unit 40. The heat supplied from the heat supply unit 50 includes at least one of renewable energy heat and waste heat from a heat pump. Renewable energy heat includes solar heat, geothermal heat, and waste heat generated when external equipment such as a heat pump is operated using power generated by solar heat, geothermal heat, or wind power. The heat pump is, for example, an outdoor or indoor unit of an air conditioner, or a water heater.

[0027] As shown in Figure 5, the heat supply unit 50 includes a heat source 51 and a fan 52. The heat source 51 is a heat collector that collects at least one of the following: renewable energy heat and waste heat from a heat pump. The fan 52 transports the air (hot air) heated by the heat source 51 to the separation unit 40. If the supplied heat is waste heat from a heat pump such as the outdoor or indoor unit of an air conditioner, the fan provided in the outdoor or indoor unit may be used to transport the air heated by the heat source 51 to the separation unit 40. In this case, the fan 52 may be omitted.

[0028] The separation unit 40 separates carbon dioxide from the adsorption member 10 (adsorbent 11). Generally, in the adsorbent 11, the equilibrium adsorption amount of carbon dioxide is greater at lower temperatures and smaller at higher temperatures. Also, the equilibrium adsorption amount of carbon dioxide is greater at higher pressures and smaller at lower pressures. By utilizing these characteristics and changing the temperature and / or pressure, carbon dioxide is adsorbed and separated by the adsorption member 10. Adsorption and separation of carbon dioxide due to temperature changes is called thermal swing adsorption (TSA), and adsorption and separation of carbon dioxide due to pressure changes is called pressure swing adsorption (PSA). In this embodiment, carbon dioxide is separated from the adsorption member 10 in the separation unit 40 using thermal swing adsorption. In other words, the separation unit 40 separates carbon dioxide from the multiple adsorption members 10 by heating them with heat supplied from the heat supply unit 50.

[0029] The separation unit 40 is installed downstream of the heat supply unit 50 in the direction of airflow generated by the fan 52. The separation unit 40 is connected to the heat supply unit 50 via the heat supply piping P1. The fan 52 of the heat supply unit 50 drives air heated by the heat source 51 to the separation unit 40 via the heat supply piping P1. The separation unit 40 is configured to hold the adsorption member 10 at a position that receives the airflow generated by the fan 52. In the following description, in the separation unit 40, one direction perpendicular to the Z direction is referred to as the X2 direction (first direction), and the direction perpendicular to both the X2 direction and the Z direction is referred to as the Y2 direction. The separation unit 40 and the heat supply unit 50 face each other in the X2 direction. Depending on the layout of each component of the gas recovery device 1, the X1 direction and the X2 direction may be the same direction or different directions.

[0030] The separation unit 40 has a separation container 41 that can accommodate a plurality of adsorption members 10 and is breathable. The separation container 41 is a box-shaped container. The separation container 41 has a first side surface 42 and a second side surface 43 that face each other in the X2 direction. The first side surface 42 faces the fan 52 of the heat supply unit 50 in the X2 direction. The first side surface 42 is provided with a plurality of first openings 42a that serve as air inlets. The second side surface 43 is provided with a plurality of second openings 43a that serve as air outlets. When the fan 52 of the heat supply unit 50 is driven, the air heated by the heat source 51 flows through the separation container 41 in the X2 direction from the first openings 42a to the second openings 43a. That is, the X2 direction is the direction in which the airflow flows within the separation container 41.

[0031] In the illustrated example, the heat supply pipe P1 is the same size as the separation container 41. However, the heat supply pipe P1 may be smaller than the separation container 41. Also, if the heat supply pipe P1 is the same size as the separation container 41, the separation container 41 does not need to have a first side surface 42, and the separation container 41 and the heat supply pipe P1 do not need to be separated.

[0032] Inside the separation container 41, a separation section arrangement region A2 is formed where a plurality of adsorption members 10 are arranged. In the separation section arrangement region A2, the plurality of adsorption members 10 are arranged in a line in the X2 direction. That is, in the separation section arrangement region A2, the plurality of adsorption members 10 are arranged in series with respect to the X2 direction. Note that at least the first adsorption member 10A and the second adsorption member 10B of the plurality of adsorption members 10 are arranged in the X2 direction. In addition, in the separation section arrangement region A2, the adsorption members 10 are arranged so that the ventilation portion 10b faces the X2 direction. That is, in the separation section arrangement region A2, the adsorption members 10 are arranged so that the axial direction of the adsorption members 10 coincides with the X2 direction. In the separation section arrangement region A2, the plurality of adsorption members 10 are arranged so that the ventilation portions 10b face each other.

[0033] In the separation section 40, the length of the separation section location area A2 in the X2 direction is longer than the length of the separation section location area A2 in the direction perpendicular to the X2 direction (the Z direction in the illustrated example). In other words, in the separation container 41, the length of the first side surface 42 and the second side surface 43 in the X2 direction is longer than the length of the first side surface 42 or the second side surface 43 in the direction perpendicular to the X2 direction (the Z direction in the illustrated example).

[0034] The fan 52 of the heat supply unit 50 drives the adsorption member 10 housed in the separation container 41, exposing it to air (hot air) heated by the heat source 51. Since the equilibrium adsorption amount of carbon dioxide by the adsorbent 11 at the temperature of the air heated by the heat source 51 is smaller than the equilibrium adsorption amount at room temperature, carbon dioxide is desorbed from the adsorbent 11. Therefore, the carbon dioxide adsorbed on the adsorption member 10 (adsorbent 11) is separated from the adsorption member 10. In the example shown in Figure 5, the fan 52 drives the first adsorption member 10A to heated air (hot air), and the air that has passed through the first adsorption member 10A exposes the second adsorption member 10B, located downstream of the first adsorption member 10A, to the hot air. Hereinafter, the gas after passing through the separation container 41 will be referred to as the recovered gas. The recovered gas contains carbon dioxide separated from the adsorption member 10.

[0035] The storage unit 60 is connected to the separation unit 40 via the recovery piping P2. The recovered gas containing carbon dioxide separated from the adsorption member 10 in the separation unit 40 is transported to the storage unit 60 via the recovery piping P2. The recovered gas may also be transported from the separation unit 40 to the storage unit 60 using the airflow generated by the operation of the fan 52. The storage unit 60 stores the carbon dioxide separated from the adsorption member 10 in the separation unit 40. The storage unit 60 has, for example, a cylinder capable of storing carbon dioxide. In the storage unit 60, carbon dioxide may be concentrated and compressed from the recovered gas for storage, or the carbon dioxide may be liquefied and stored. Note that the storage unit 60 is not an essential component and may be omitted.

[0036] As described above, the gas recovery device 1 according to this embodiment includes a separation unit 40 that separates the target gas from a plurality of adsorption members 10 that have adsorbed the target gas. The separation unit 40 has a separation container 41 capable of housing the plurality of adsorption members 10. Each of the plurality of adsorption members 10 has an outer peripheral portion 10a and a ventilation portion 10b that has lower airflow resistance than the outer peripheral portion 10a. Inside the separation container 41, the plurality of adsorption members 10 are arranged so that their ventilation portions 10b face each other.

[0037] With this gas recovery device 1, an airflow for separating the target gas can be generated simultaneously within the separation container 41 for multiple adsorption members 10. Therefore, the flow rate of the airflow for separating the target gas can be reduced, and the separation energy required to separate the target gas from the adsorption members 10 can be reduced. As a result, the recovery efficiency of the target gas is improved. In addition, because the flow rate of the airflow for separating the target gas is reduced, the concentration of the target gas in the recovered gas after passing through the separation container 41 increases. From this point of view as well, the recovery efficiency of the target gas is improved.

[0038] Furthermore, the multiple adsorption members 10 include a first adsorption member 10A and a second adsorption member 10B. The separation container 41 is configured so that airflow flows in the X2 direction (first direction) within the separation container 41. Within the separation container 41, the first adsorption member 10A and the second adsorption member 10B are arranged in the X2 direction. With the above configuration, the flow rate of the airflow for separating the target gas can be reduced more effectively, and the separation energy when separating the target gas from the adsorption members 10 can be reduced more effectively.

[0039] Furthermore, in the adsorption member 10, the length of the adsorption member 10 in the direction of airflow is smaller than the outer diameter of the ventilation section 10b. With the above configuration, the length of the adsorption member 10 in the direction of airflow is shortened, which reduces the airflow resistance of the adsorption member 10. Therefore, the separation energy required to separate the target gas from the adsorption member 10 can be reduced more effectively.

[0040] Furthermore, the gas recovery device 1 further includes an adsorption unit 30 that adsorbs the target gas contained in the mixed gas with a plurality of adsorption members 10. The adsorption unit 30 has an adsorption container 31 capable of housing the plurality of adsorption members 10. The adsorption container 31 is configured so that airflow flows in the X1 direction (second direction) within the adsorption container 31. Within the adsorption container 31, the first adsorption member 10A and the second adsorption member 10B are arranged in directions perpendicular to the X1 direction. For example, in the adsorption unit 30, the airflow generated by the air blower 20, such as the outdoor or indoor unit of an air conditioning system or a ventilation fan, may be used to adsorb the target gas with the adsorption members 10. In this case, if the airflow resistance due to the adsorption members 10 is large in the adsorption unit 30, the primary function of the air blower 20 (for example, if the air blower 20 is the outdoor or indoor unit of an air conditioning system, it is the heat exchange performance; if the air blower 20 is a ventilation fan, it is the air blowing capacity) will be reduced. With the above configuration, the first adsorption member 10A and the second adsorption member 10B are arranged in a direction perpendicular to the X1 direction within the adsorption container 31, so that the airflow resistance caused by the adsorption members 10 (10A, 10B) in the adsorption section 30 is reduced. Therefore, in the adsorption section 30, the target gas can be adsorbed by the adsorption members 10 using the airflow generated by the air blower 20 while suppressing a decrease in the primary function of the air blower 20. As a result, the adsorption energy required to adsorb the target gas onto the adsorption members 10 can be reduced, and the recovery efficiency of the target gas is improved.

[0041] Furthermore, in the separation section 40, the separation section arrangement region A2, where multiple adsorption members 10 are arranged, has a length in the X2 direction that is longer than the length in the direction perpendicular to the X2 direction. In the adsorption section 30, the adsorption section arrangement region A1, where multiple adsorption members 10 are arranged, has a length in the X1 direction that is shorter than the length in the direction perpendicular to the X1 direction. With the above configuration, the adsorption energy when adsorbing the target gas onto the adsorption members 10, and the separation energy when separating the target gas from the adsorption members 10, can be reduced more effectively.

[0042] Furthermore, within the adsorption container 31, the multiple adsorption members 10 are arranged so that the ventilation portion 10b faces the X1 direction. With this configuration, the adsorption energy when adsorbing the target gas onto the adsorption members 10 can be reduced more effectively.

[0043] Further, the gas recovery device 1 further includes a heat supply unit 50 that supplies heat to the separation unit 40. The separation unit 40 separates the target gas from the plurality of adsorption members 10 by heating the plurality of adsorption members 10 with the heat supplied from the heat supply unit 50. According to the above configuration, in the separation unit 40, carbon dioxide can be separated from the adsorption member 10 using temperature swing adsorption. Further, when the supplied heat from the heat supply unit 50 is renewable energy heat, waste heat of a heat pump, or the like, the separation energy for separating the target gas from the adsorption member 10 can be more effectively reduced.

[0044] Further, the adsorption member 10 includes an adsorbent 11 and a container 12 that houses the adsorbent 11. The container 12 has a cylindrical shape with both ends open, and includes a protective material 13 (first member) that forms the outer peripheral portion 10a, and two air-permeable members 14 (second members) that are provided at both ends of the protective material 13 and form the ventilation portion 10b. The axial length of the protective material 13 is smaller than the diameter of the protective material 13. According to the above configuration, as the adsorbent 11, for example, adsorbents having various shapes such as spherical or cylindrical can be adopted. Further, since the adsorbent 11 is housed in the container 12, damage to the adsorbent 11 can be prevented. Further, since the axial length of the protective material 13 is shortened, the ventilation resistance of the adsorption member 10 can be suppressed. Therefore, the separation energy for separating the target gas from the adsorption member 10 can be more effectively reduced.

[0045] Embodiment 2. Next, referring to FIGS. 6 and 7, a gas recovery device according to Embodiment 2 will be described. Since the basic configuration of the gas recovery device according to the present embodiment is the same as that of Embodiment 1, the description will focus on the differences.

[0046] In this embodiment, in the separation unit 40, carbon dioxide is separated from the adsorption member 10 by using pressure swing adsorption. Specifically, as shown in FIG. 6, the gas recovery device 1 according to this embodiment includes a pressure fluctuation device 70 instead of the heat supply unit 50. The pressure fluctuation device 70 is installed on the downstream side of the separation unit 40. The pressure fluctuation device 70 changes the pressure in the separation container 41. The separation unit 40 separates carbon dioxide from the plurality of adsorption members 10 by reducing the pressure in the separation container 41 by the pressure fluctuation device 70.

[0047] As shown in FIG. 7, the pressure fluctuation device 70 is connected to the separation unit 40 via a suction pipe P3. The pressure fluctuation device 70 has a vacuum pump 71. The vacuum pump 71 reduces the pressure in the separation container 41 by sucking the gas in the separation container 41 through the suction pipe P3. At this time, in the separation container 41, the air flow flows in the X2 direction. By operating the vacuum pump 71, the pressure in the separation container 41 becomes a low pressure state lower than the atmospheric pressure. The pressure in the separation container 41 may be, for example, -90 kPa or lower than -90 kPa with respect to the atmospheric pressure, or the inside of the separation container 41 may be in a vacuum state. Since the equilibrium adsorption amount of carbon dioxide of the adsorbent 11 in the low pressure state is smaller than the equilibrium adsorption amount at the atmospheric pressure, the desorption of carbon dioxide from the adsorbent 11 occurs. Therefore, the carbon dioxide adsorbed on the adsorption member 10 (adsorbent 11) is separated from the adsorption member 10.

[0048] The storage unit 60 is connected to the pressure fluctuation device 70 via a recovery pipe P2. The recovery gas containing carbon dioxide separated from the adsorption member 10 in the separation unit 40 is conveyed to the storage unit 60 via the recovery pipe P2. The recovery gas may be conveyed to the storage unit 60 by using the air flow generated by driving the vacuum pump 71. The storage unit 60 stores the carbon dioxide separated from the adsorption member 10 in the separation unit 40.

[0049] As described above, the gas recovery apparatus 1 according to this embodiment further includes a pressure fluctuation device 70 that changes the pressure inside the separation container 41. The separation unit 40 separates the target gas from the multiple adsorption members 10 by reducing the pressure inside the separation container 41 using the pressure fluctuation device 70. With this configuration, carbon dioxide can be separated from the adsorption members 10 in the separation unit 40 using pressure swing adsorption. Therefore, compared to, for example, the case where temperature swing adsorption is used, the flow rate of the airflow for separating the target gas is reduced, and the concentration of the target gas in the recovered gas after passing through the separation container 41 can be increased.

[0050] Embodiment 3. Next, with reference to Figure 8, a gas recovery device according to Embodiment 3 will be described. The gas recovery device according to this embodiment has the same basic configuration as Embodiments 1 and 2, so the differences will be explained in detail.

[0051] In this embodiment, carbon dioxide is separated from the adsorption member 10 in the separation unit 40 using both temperature swing adsorption and pressure swing adsorption. The gas recovery device 1 according to this embodiment includes both a heat supply unit 50 and a pressure fluctuation device 70. The heat supply unit 50 is installed upstream of the separation unit 40, and the pressure fluctuation device 70 is installed downstream of the separation unit 40.

[0052] The separation of carbon dioxide using the heat supply unit 50 and the separation of carbon dioxide using the pressure fluctuation device 70 may be performed simultaneously or alternately. Alternatively, only the separation of carbon dioxide using the heat supply unit 50 may be performed, or only the separation of carbon dioxide using the pressure fluctuation device 70 may be performed.

[0053] When carbon dioxide separation using the heat supply unit 50 and carbon dioxide separation using the pressure fluctuation device 70 are performed simultaneously, the airflow of the fan 52 of the heat supply unit 50 may be adjusted so that the pressure fluctuation device 70 can reduce the pressure inside the separation container 41 even when the fan 52 is running.

[0054] When carbon dioxide separation using the heat supply unit 50 and carbon dioxide separation using the pressure fluctuation device 70 are performed alternately, the heat supply pipe P1 may be provided with an on-off valve for opening and closing the heat supply pipe P1. When carbon dioxide separation is performed using the heat supply unit 50, this on-off valve is set to the open state, and when carbon dioxide separation is performed using the pressure fluctuation device 70, this on-off valve is set to the closed state. This allows for effective depressurization of the separation container 41 when carbon dioxide separation is performed using the pressure fluctuation device 70. When carbon dioxide separation using the pressure fluctuation device 70 is performed after carbon dioxide separation using the heat supply unit 50, the adsorption member 10 is heated by the heat supply unit 50 at least in the initial stage of carbon dioxide separation using the pressure fluctuation device 70. At this time, in the separation unit 40, the adsorption member 10 is exposed to a high temperature and low pressure state, so the amount of carbon dioxide desorbed can be increased.

[0055] As described above, the gas recovery apparatus 1 according to this embodiment further comprises a heat supply unit 50 that supplies heat to the separation unit 40, and a pressure fluctuation device 70 that changes the pressure inside the separation container 41. The separation unit 40 separates the target gas from the multiple adsorption members 10 by heating the multiple adsorption members 10 with heat supplied from the heat supply unit 50, and by reducing the pressure inside the separation container 41 using the pressure fluctuation device 70, at least one of the above. With the above configuration, by combining temperature swing adsorption and pressure swing adsorption, the amount of target gas separated from the adsorption members 10 can be increased, and the concentration of the target gas in the recovered gas after passing through the separation container 41 can be further increased.

[0056] The technical scope of this disclosure is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of this disclosure.

[0057] For example, in the above embodiment, the axial length of the adsorption member 10 is smaller than the outer diameter of the ventilation portion 10b. However, the disclosure is not limited thereto. The axial length of the adsorption member 10 may be greater than or equal to the outer diameter of the ventilation portion 10b. Even in this case, as shown in Figure 9, in the adsorption portion arrangement area A1 of the adsorption portion 30, the multiple adsorption members 10 are arranged in a direction perpendicular to the X1 direction (the Z direction in the illustrated example). Also, in the adsorption portion arrangement area A1, the adsorption members 10 are arranged so that the ventilation portion 10b faces the X1 direction. As shown in Figure 10, in the separation portion arrangement area A2 of the separation portion 40, the multiple adsorption members 10 are arranged in a direction parallel to the X2 direction. Also, in the separation portion arrangement area A2, the adsorption members 10 are arranged so that the ventilation portion 10b faces the X2 direction. In the separation portion arrangement area A2, the multiple adsorption members 10 are arranged so that the ventilation portions 10b face each other.

[0058] Furthermore, in the above embodiment, the adsorption member 10 is cylindrical. However, the disclosure is not limited thereto. The adsorption member 10 may also be prismatic. In this case, the container 12 of the adsorption member 10 comprises a rectangular tube-shaped protective material 13 that forms the outer circumference 10a and a polygonal breathable member 14 that forms the ventilation portion 10b. Also, the diameter of the circumscribed circle of the ventilation portion 10b (breathable member 14) corresponds to the outer diameter of the ventilation portion 10b (breathable member 14). When viewed from the axial direction, the diameter of the circumscribed circle of the protective material 13 corresponds to the diameter of the protective material 13.

[0059] Furthermore, in the above embodiment, the adsorption member 10 includes a plurality of adsorbents 11 and a container 12 that houses the plurality of adsorbents 11. However, the disclosure is not limited thereto. As shown in Figure 11, the adsorption member 10 may have a configuration that includes an adsorbent 81 which is a cylindrical honeycomb material and a cylindrical protective material 82 which covers the outer circumferential surface of the adsorbent 81. In this case, the protective material 82 forms the outer circumferential portion 10a, and the axial end of the adsorbent 81 forms the ventilation portion 10b. Alternatively, the adsorption member 10 may have a configuration that includes only an adsorbent 81 which is a cylindrical honeycomb material. In this case, the outer circumferential portion of the adsorbent 81 forms the outer circumferential portion 10a, and the axial end of the adsorbent 81 forms the ventilation portion 10b.

[0060] Other embodiments or modifications described above may be combined as appropriate.

[0061] 1 Gas recovery device 10 Adsorption member 10a Outer periphery 10b Ventilation part 11 Adsorbent 12 Container 13 Protective material (first member) 14 Ventilated member (second member) 30 Adsorption part 31 Adsorption container 40 Separation part 41 Separation container 50 Heat supply part 70 Pressure fluctuation device A1 Adsorption part arrangement area A2 Separation part arrangement area

Claims

1. A gas recovery device comprising: a separation unit for separating a target gas from a plurality of adsorbent members that have adsorbed the target gas, wherein the separation unit has a separation container capable of housing the plurality of adsorbent members, each of the plurality of adsorbent members has an outer circumference and a ventilation portion having lower airflow resistance than the outer circumference, and the plurality of adsorbent members are arranged in the separation container such that the ventilation portions face each other.

2. The gas recovery apparatus according to claim 1, wherein the plurality of adsorption members comprises a first adsorption member and a second adsorption member, the separation container is configured such that an airflow flows in a first direction within the separation container, and the first adsorption member and the second adsorption member are arranged in the first direction within the separation container.

3. The gas recovery device according to claim 1 or 2, wherein the length of the adsorption member in the direction in which the airflow flows through the adsorption member is smaller than the outer diameter of the ventilation portion.

4. The gas recovery device according to claim 2, further comprising an adsorption unit for adsorbing the target gas contained in the mixed gas with the plurality of adsorption members, wherein the adsorption unit has an adsorption container capable of accommodating the plurality of adsorption members, the adsorption container is configured such that an airflow flows in a second direction within the adsorption container, and within the adsorption container, the first adsorption member and the second adsorption member are arranged in directions perpendicular to the second direction.

5. The gas recovery apparatus according to claim 4, wherein in the separation section, the separation section arrangement region in which the plurality of adsorption members are arranged has a length in the first direction that is longer than the length in the direction perpendicular to the first direction, and in the adsorption section, the adsorption section arrangement region in which the plurality of adsorption members are arranged has a length in the second direction that is shorter than the length in the direction perpendicular to the second direction.

6. The gas recovery apparatus according to claim 4 or 5, wherein the plurality of adsorption members are arranged in the adsorption container such that the ventilation portion faces the second direction.

7. A gas recovery apparatus according to any one of claims 1 to 6, further comprising a heat supply unit that supplies heat to the separation unit, wherein the separation unit separates the target gas from the plurality of adsorption members by heating the plurality of adsorption members with heat supplied from the heat supply unit.

8. A gas recovery apparatus according to any one of claims 1 to 6, further comprising a pressure fluctuation device for changing the pressure inside the separation container, wherein the separation unit separates the target gas from the plurality of adsorption members by reducing the pressure inside the separation container with the pressure fluctuation device.

9. A gas recovery apparatus according to any one of claims 1 to 6, further comprising: a heat supply unit that supplies heat to the separation unit; and a pressure fluctuation device that changes the pressure inside the separation container, wherein the separation unit separates the target gas from the plurality of adsorption members by performing at least one of the following: heating the plurality of adsorption members with heat supplied from the heat supply unit, and reducing the pressure inside the separation container with the pressure fluctuation device.

10. The gas recovery device according to any one of claims 1 to 9, wherein the adsorption member comprises an adsorbent and a container for containing the adsorbent, the container having a cylindrical shape with open ends and a first member forming the outer circumference, and two second members provided at both ends of the first member and forming the ventilation portion, the axial length of the first member being smaller than the diameter of the first member.

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