Gas adsorption device

Abstract

To provide a gas adsorption device that promotes detachment of a gas molecule that is adsorbed by an adsorption layer with a method with a less energy loss.SOLUTION: A gas adsorption device (10) according to one embodiment includes: a housing (12); an adsorption layer (16) accommodated in the housing and including an adsorbent for adsorbing a specific gas component from a mixed gas that is introduced into the housing (12); and a heater (20) disposed in the housing (12). The adsorption layer (16) is configured so as to be movable in the housing (12), moves in a direction of separating from the heater (20) when adsorbing the gas component, and moves in a direction of approaching the heater when detaching the gas component.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The technology disclosed in this application relates to a gas adsorption device. [Background technology]

[0002] Gas adsorption devices that adsorb specific gas components in a mixed gas using an adsorption layer housed in a housing are known. For example, the adsorption device disclosed in Japanese Patent Laid-Open No. 2023-147269 uses zeolite capable of adsorbing carbon dioxide as an adsorbent constituting the adsorption layer, and is suitable for removing carbon dioxide from natural gas. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-147269 Summary of the Invention [Problem to be solved by the invention]

[0004] Gas molecules adsorbed in an adsorption layer are typically desorbed using a purge gas. To promote desorption, a heating device is installed near the adsorption layer, which heats the adsorption layer during desorption operation and cools the adsorption layer by turning off the heating device during adsorption operation. However, this method involves repeated heating and cooling of the adsorption layer with each adsorption / desorption cycle, resulting in significant thermal energy loss. This energy loss is particularly significant when a thermal insulator with a large heat capacity is present in the surrounding area. Furthermore, reducing the frequency of switching between adsorption and desorption to reduce this loss requires increasing the amount of adsorbent that makes up the adsorption layer, which increases the size and manufacturing costs of the adsorption device. Therefore, it is desirable to promote desorption of adsorbed gas molecules using a method that minimizes energy loss. [Means for solving the problem]

[0005] One aspect of the present technology is a gas adsorption device comprising: a housing; an adsorption layer (16) accommodated in the housing and containing an adsorbent that adsorbs a specific gas component in a mixed gas introduced into the housing; and a heating device (16) disposed within the housing, wherein the adsorption layer (16) is configured to be movable within the housing, moving away from the heating device when adsorbing the gas component and moving toward the heating device when desorbing the gas component. This allows the adsorption layer (16) to be heated and cooled by moving it, thereby reducing the loss of thermal energy associated with the adsorption-desorption cycle.

[0006] In some embodiments, the housing includes a mixed gas inlet for introducing the mixed gas, and a purge gas inlet for introducing a purge gas for desorbing the gas components adsorbed to the adsorbent, wherein the adsorption bed moves away from the heating device due to the pressure of the mixed gas flowing in through the mixed gas inlet during adsorption, and moves toward the heating device due to the pressure of the purge gas flowing in through the purge gas inlet during desorption. This allows the adsorption bed to move without a separate driving source.

[0007] In some embodiments, the gas adsorption device further includes a first biasing member that biases the adsorption layer away from the heating device and a second biasing member that biases the adsorption layer toward the heating device. This ensures that the adsorption layer is securely supported from both sides and allows smooth movement of the adsorption layer. This also increases the flexibility of the orientation of the gas adsorption device.

[0008] In some embodiments, the housing is cylindrical, the mixed gas inlet is located at one end of the housing, the purge gas inlet is located at the other end of the housing, and the adsorption bed moves linearly between the mixed gas inlet and the purge gas inlet, thereby allowing the adsorption bed to move in a simple manner.

[0009] In some embodiments, the device further includes a magnet movably mounted on the outside of the housing, an actuator for driving the magnet, and a magnetic body mounted on the attraction layer, and the attraction layer is moved by the magnetic force of the magnet driven by the actuator, thereby ensuring reliable movement of the attraction layer.

[0010] In some embodiments, the device further includes a solenoid coil provided on the outside of the housing and a magnetic body provided on the attraction layer, and the attraction layer is moved by the magnetic force of the solenoid coil, thereby ensuring reliable movement of the attraction layer.

[0011] In some embodiments, the specific gas component is ammonia, which enables the adsorption and desorption of ammonia with little energy loss. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 2 is a cross-sectional view of a gas adsorption device according to one embodiment operating in an adsorption mode. [Figure 2] FIG. 2 is a cross-sectional view of the gas adsorption device of FIG. 1 during operation in a desorption mode. DETAILED DESCRIPTION OF THE INVENTION

[0013] Various embodiments will be described below with reference to the drawings.

[0014] [Gas adsorption apparatus] 1 shows an embodiment of a gas adsorption device 10 used to adsorb molecules of specific gas components from a mixed gas. For example, the gas adsorption device 10 can be used to adsorb residual ammonia from a mixed gas obtained by ammonia decomposition, adsorb carbon dioxide from the exhaust gas of a combustion engine, or adsorb fuel vapor from excess gas generated in a fuel tank. The gas adsorption device 10 takes in a mixed gas containing the gas component to be adsorbed (e.g., ammonia) from a supply source (not shown) and discharges the gas from which the gas component has been sufficiently removed. The discharged gas is sent to a device or facility (not shown) for use or storage.

[0015] [housing] 1, a gas adsorption device 10 includes a housing 12 and an adsorption layer 16 housed within the housing 12. The housing 12 is provided with a mixed gas inlet 13 and a mixed gas outlet 14. In one embodiment, the housing 12 is cylindrical, with the mixed gas inlet 13 located at the top end of the housing 12 and the mixed gas outlet 14 located at the bottom end of the housing 12. The housing 12 is formed from, for example, polytetrafluoroethylene (PTFE), quartz glass, or the like.

[0016] [Adsorption layer] Adsorption layer 16 is disposed within housing 12. Adsorption layer 16 includes an adsorbent capable of adsorbing and desorbing a specific gas component, such as carbon dioxide. The adsorbent is a material that is easily heated. The adsorbent includes a solid material capable of adsorbing molecules of the target gas component, such as zeolite, silica gel, activated carbon, or a combination thereof, and may further include other components such as a binder. Adsorption layer 16 may be an aggregate of discrete adsorbents, such as granules, pellets, or powder. In another embodiment, adsorption layer 16 may be a monolithic structure having numerous pores or passages, such as a honeycomb structure.

[0017] [Holding member] The adsorption layer 16, which is made up of discrete aggregates of adsorbent, is held by sandwiching it from both sides between presser members 18, 19, which may be, for example, resin plates or the like having numerous holes (not shown) that are smaller than the particle size of the adsorbent. In another embodiment (not shown), a breathable filter made of a urethane foam sheet, nonwoven fabric, quartz fiber sheet, or the like may be placed between the adsorption layer 16 and the presser members 18, 19. In this case, the presser members 18, 19 may be, for example, resin plates having voids larger than the particle size of the adsorbent.

[0018] [Heating device] 1, gas adsorption device 10 has heating device 20 (heater) disposed inside or outside housing 12. Heating device 20 is disposed so as to create a heated region 21 and a non-heated region 22 within housing 12. Non-heated region 22 is a region that is not actively heated by heating device 20, or a region that is little affected by heating device 20 and maintains a temperature close to room temperature. For example, heating device 20 is disposed near mixed gas inlet 13 on the outside of housing 12, and a heated region 21 is formed within housing 12 near mixed gas inlet 13.

[0019] A heat insulating material 24 can be arranged on the outside of the housing 12. The heat insulating material 24 is arranged, for example, adjacent to the outside of the heating device 20. Also, it is possible to avoid placing any heat insulating material (especially one with a large heat capacity) in the position corresponding to the non-heated region 22.

[0020] 1 and 2, the adsorption layer 16 is configured to be movable between a heated region 21 and a non-heated region 22 in the housing 12 while being sandwiched between the pressing members 18 and 19. For example, the pressing members 18 and 19 may be made thick and disk-shaped, and the housing 12 may be made cylindrical, so that the pressing members 18 and 19 can slide inside the housing 12. It is also possible to limit the movable range of the adsorption layer 16 by providing the housing 12 with stoppers 26 and 27 in the form of ribs or the like protruding from the inner surface.

[0021] The adsorption bed 16 is sandwiched between the presser members 18 and 19 and elastically supported in the housing 12 by biasing members such as compression springs 28 and 29. Specifically, a compression spring 28 that biases the adsorption bed 16 in a direction away from the heating device 20 (toward the non-heating region 22) is disposed between the adsorption bed 16 and the mixed gas inlet 13. Another compression spring 29 that biases the adsorption bed 16 in a direction toward the heating device 20 (toward the heating region 21) is disposed between the adsorption bed 16 and the mixed gas outlet 14. When the gas adsorption device 10 is not operating, i.e., when there is no flow within the housing 12, the adsorption bed 16 is in a neutral position (not shown).

[0022] [Adsorption and desorption of gas components] As shown in FIG. 1, in the adsorption mode, a mixed gas containing a specific gas component to be adsorbed is introduced from a supply source into housing 12 through mixed gas inlet 13. As the mixed gas passes through adsorption layer 16, molecules of the specific gas component are adsorbed onto adsorption layer 16. Furthermore, the pressure of the mixed gas flowing in from the mixed gas inlet (the force acting on pressure member 18 and the adsorbent) causes adsorption layer 16 to move away from heating device 20. Adsorption layer 16 eventually enters non-heated region 22 (the state shown in FIG. 1) and is cooled to a temperature suitable for adsorption (e.g., room temperature). While the mixed gas passes through heated region 21 before reaching adsorption layer 16, it is barely heated due to the short passage time. The remaining mixed gas, from which the specific gas component has been sufficiently removed, is discharged from mixed gas outlet 14.

[0023] As shown in FIG. 2, molecules of a specific gas component adsorbed on the adsorbent can be desorbed by flowing a purge gas in the opposite direction to the adsorption. The purge gas is introduced into the housing 12 from a supply source (not shown) through the mixed gas outlet 14 (purge gas inlet) and passes through the adsorption layer 16. During this process, the gas molecules adsorbed on the adsorbent begin to desorb. The pressure of the purge gas flowing in from the purge gas inlet (the force acting on the pressure member 19 and the adsorbent) causes the adsorption layer 16 to move toward the heating device 20. The adsorption layer 16 eventually enters the heating region 21 (as shown in FIG. 2) and reaches a temperature that promotes desorption of the adsorbed gas molecules. In a specific embodiment, when ammonia is adsorbed on zeolite, the adsorption layer 16 is heated to approximately 350°C. The desorbed gas molecules are discharged together with the purge gas from the mixed gas inlet 13 (purge gas outlet). In another embodiment (not shown), the purge gas inlet and the purge gas outlet can be provided separately from the mixed gas outlet 14 and the mixed gas inlet 13 .

[0024] As described above, the adsorption layer 16 can be heated and cooled by moving it between the heated region 21 and the unheated region 22, thereby reducing the loss of thermal energy associated with the adsorption-desorption cycle. In particular, even when a thermal insulator with a large heat capacity is placed outside the heating device 20, the adsorption mode and desorption mode can be switched in a short time without being affected by the heat absorption or heat generation of the thermal insulator. Furthermore, since the frequency of mode switching can be increased, the amount of adsorbent constituting the adsorption layer can be reduced, leading to the possibility of downsizing the gas adsorption device 10. In one embodiment, the heating device 20 can be turned off in the desorption mode. In another embodiment, the heating device 20 can be kept on at all times during operation of the gas adsorption device 10.

[0025] [Use of power sources other than gas] In another embodiment (not shown), in addition to using the pressure of the gas flow, a separate driving source can be provided outside the housing to reliably move the adsorption layer. In one specific embodiment, a magnetic body can be placed on the adsorption layer or the case housing the adsorption layer, and the adsorption layer can be moved from outside the housing using magnetic force. For example, a magnet can be placed on the outside of the housing to attract the magnetic body, and an appropriate actuator can be used to move the adsorption layer to a heated or unheated area. In another embodiment, a solenoid coil can be placed on the outside of the housing instead of a (permanent) magnet. In this case, a return spring is placed between the adsorption layer and the housing. When the solenoid coil is energized, the magnetic body is attracted, causing the adsorption layer to move in one direction against the spring. When the solenoid coil is deenergized, the force of the spring causes the adsorption layer to move in the opposite direction. In yet another embodiment, the adsorption layer can be moved against the gas flow without using the pressure of the gas flow.

[0026] [Non-linear movement of the adsorbed layer] In the above embodiment, the adsorption layer has been described as moving linearly within the cylindrical housing between the mixed gas inlet 13 and the mixed gas outlet 14. However, in another embodiment (not shown), the housing may have a non-linear shape, such as a U-shape, or the adsorption layer may move non-linearly, such as by rotating around some axis, to move between the heated region and the non-heated region.

[0027] Although various embodiments have been described above, the scope of the present technology is not limited to these embodiments. Those skilled in the art may make various modifications, substitutions, additions, omissions, and improvements. [Explanation of symbols]

[0028] 10 Gas adsorption apparatus 12 Housing 13 Mixed gas inlet 14 Mixed gas outlet (purge gas inlet) 16 Adsorption layer 18, 19 Holding member 20 Heating device 21 Heating area 22 Non-heating area 24 Insulation 26, 27 Stopper 28, 29 Compression spring

Claims

1. 1. A gas adsorption apparatus comprising: Housing and an adsorption layer accommodated in the housing and including an adsorbent that adsorbs a specific gas component in the mixed gas introduced into the housing; a heating device disposed within the housing; The adsorption layer is configured to be movable within the housing, and moves away from the heating device when adsorbing the gas components, and moves toward the heating device when desorbing the gas components.

2. 2. The gas adsorption apparatus of claim 1, a mixed gas inlet formed in the housing for introducing the mixed gas; a purge gas inlet formed in the housing for introducing a purge gas for desorbing the gas component adsorbed by the adsorbent, a gas adsorption device in which, during adsorption, the adsorption layer moves in a direction away from the heating device due to the pressure of the mixed gas flowing in from the mixed gas inlet, and, during desorption, the adsorption layer moves in a direction toward the heating device due to the pressure of the purge gas flowing in from the purge gas inlet.

3. The gas adsorption apparatus of claim 2, a first biasing member that biases the adsorption layer in a direction away from the heating device; a second biasing member that biases the adsorption layer in a direction toward the heating device.

4. The gas adsorption apparatus of claim 2, the housing is cylindrical, the mixed gas inlet is provided at one end of the housing, and the purge gas inlet is provided at the other end of the housing; The gas adsorption device, wherein the adsorption bed moves linearly between the mixed gas inlet and the purge gas inlet.

5. 2. The gas adsorption apparatus of claim 1, a magnet movably provided on the outside of the housing; an actuator that drives the magnet; a magnetic material provided on the adsorption layer, The gas adsorption device, wherein the adsorption layer is moved by the magnetic force of the magnet driven by the actuator.

6. 2. The gas adsorption apparatus of claim 1, a solenoid coil provided outside the housing; a magnetic material provided on the adsorption layer, The gas adsorption device, wherein the adsorption layer is moved by the magnetic force of the solenoid coil.

7. The gas adsorption apparatus according to any one of claims 1 to 6, A gas adsorption device in which the specific gas component is ammonia.

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