Adsorbent regenerative apparatus and removal system

Abstract

To enable a single execution of the processing of regenerating an adsorption capacity and a sufficient shortening of the time required for regeneration.SOLUTION: This apparatus comprises a blower 11 which blows hydrogen gas so as to pass through a heat exchanger 22, one of adsorption towers 2a, 2b, a heat exchanger 24 and a gas-liquid separation tank 12 in this order and so as to flow again into the heat exchange 22, connects the heat exchanger 22 with the gas inlet / outlet in the adsorption tower 2b of the regeneration target when starting the processing for regenerating adsorption capacity, connects the heat exchanger 24 with the gas inlet / outlet in the adsorption tower 2b, blows hydrogen gas at a [first blowing capacity] regulated previously by controlling the blower 11, and controls a refrigeration cycle 10 to execute the heating of hydrogen gas in the heat exchanger 22 and the cooling of hydrogen gas in the heat exchanger 24, thereby controlling the blower 11, when requirements regulated previously are satisfied during the execution of the processing for generating adsorption capacity, to pass hydrogen gas at a [second blowing capacity] regulated lower than [first blowing capacity.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an adsorbent regeneration device configured to be capable of regenerating an adsorbent in a removal system capable of performing an adsorption removal process in which a target substance contained in a gas is adsorbed onto an adsorbent in an adsorption tower and removed, and to a removal system configured to be equipped with such an adsorbent regeneration device and to be capable of performing an adsorption removal process and an adsorption capacity regeneration process. [Background technology]

[0002] For example, when removing moisture contained in hydrogen gas from the hydrogen gas, an adsorption removal process is widely carried out in which the hydrogen gas is introduced into an adsorption tower and the moisture is adsorbed by an adsorbent in the adsorption tower to remove the moisture. Some adsorbents used in such adsorption removal processes are capable of restoring their adsorption capacity, and when such adsorbents are used, a thermal regeneration type adsorption capacity regeneration process is also widely carried out in which the adsorbent that has adsorbed moisture is heated to remove the moisture from the adsorbent.

[0003] In this case, in order to fully restore the adsorption capacity (to fully remove moisture from the adsorbent) without deteriorating the adsorbent due to excessive heating in the adsorption capacity regeneration process, it is necessary to continue heating the adsorbent within an appropriate temperature range for a certain period of time. This increases the time required for the adsorption capacity regeneration process. In addition, in the adsorption capacity regeneration process, an electric heater or the like is used as a heat source for heating the adsorbent. This increases the cost of removing hydrogen from hydrogen gas by the amount of energy consumed by the electric heater or the like for heating.

[0004] Meanwhile, the applicant has disclosed a removal system equipped with a plurality of adsorption towers and heat pump units and capable of performing adsorption removal processing and adsorption capacity regeneration processing in the following prior application. In this case, the removal system disclosed by the applicant adopts a configuration in which the temperature of hydrogen gas (hydrogen gas for heating the adsorbent) to be flowed into the adsorption tower performing the adsorption capacity regeneration processing is raised using the heat pump unit as a hot heat source, and the hydrogen gas containing moisture released from the adsorbent is cooled using the heat pump unit as a cold heat source, so that moisture is separated from the hydrogen gas. In addition, the removal system disclosed by the applicant adopts a configuration in which the hydrogen gas (hydrogen gas containing moisture) to be flowed into the adsorption tower performing the adsorption removal processing is cooled using the heat pump unit as a cold heat source, so that a portion of the moisture contained in the hydrogen gas is separated from the hydrogen gas before it is flowed into the adsorption tower performing the adsorption removal processing.

[0005] As a result, according to the removal system disclosed by the applicant, while an adsorption removal process is being performed in some of the adsorption towers, an adsorption capacity regeneration process can be performed in parallel in some of the other adsorption towers to regenerate the adsorption capacity, so that the adsorption removal process can be continued as a whole system. Also, according to the removal system disclosed by the applicant, a part of the moisture contained in the hydrogen gas is separated from the hydrogen gas before being flowed into the adsorption towers performing the adsorption removal process, which prevents the adsorption capacity of the adsorbent in the adsorption towers performing the adsorption removal process from decreasing in a short period of time, and thus makes it possible to secure sufficient time required for the adsorption capacity regeneration process in the other adsorption towers.

[0006] Furthermore, the removal system disclosed by the applicant employs a configuration in which the heat pump unit is used as a hot and cold source to heat and cool the hydrogen gas, as described above. This makes it possible to sufficiently reduce energy consumption and the cost required for removing hydrogen from hydrogen gas, compared to a configuration in which an electric heater is used as a hot heat source for heating the hydrogen gas, separate from a cold heat source (e.g., a refrigeration cycle) for cooling the hydrogen gas. Prior Application 1

[0007] Patent application 2022-025415 Summary of the Invention [Problem to be solved by the invention]

[0008] However, the removal system disclosed by the applicant has the following problems to be solved.

[0009] Specifically, the removal system disclosed by the applicant employs a configuration in which a heat pump unit is used as a hot heat source and a cold heat source to heat and cool hydrogen gas. In this case, the heat pump unit uses a condenser in a refrigeration cycle as a hot heat source and an evaporator as a cold heat source. In addition, in order to use the condenser as a hot heat source, it is necessary to compress a sufficient amount of refrigerant in the compressor, and for this purpose, it is necessary to vaporize a sufficient amount of refrigerant in the evaporator used as a cold heat source. In other words, in a configuration in which a heat pump unit (refrigeration cycle) is used as a hot heat source and a cold heat source, which is premised on balancing the amount of heat released in the condenser and the amount of heat absorbed in the evaporator, the amount of heat required to heat hydrogen gas needs to be absorbed in the evaporator.

[0010] However, immediately after the start of the adsorption removal process and the adsorption capacity regeneration process, the temperature of the hydrogen gas flowing into the adsorption tower where the adsorption capacity regeneration process is performed is not sufficiently high. Therefore, the temperature of the hydrogen gas passed through the adsorption tower is also low, making it difficult to absorb a sufficient amount of heat from the evaporator. In this case, the removal system disclosed by the applicant adopts a configuration in which the hydrogen gas flowing into the adsorption tower where the adsorption removal process is performed is cooled using a heat pump unit as a cold heat source, so that a part of the moisture contained in the hydrogen gas is separated from the hydrogen gas before it is flowed into the adsorption tower. As a result, even immediately after the process is started, the heat absorbed by cooling the hydrogen gas can be absorbed from the evaporator, but in an environment where the temperature of the hydrogen gas is not very high, it is still difficult to absorb a sufficient amount of heat from the evaporator.

[0011] Therefore, in the removal system disclosed by the applicant, the time required from the start of the adsorption removal process and the adsorption capacity regeneration process until the hydrogen gas to be introduced into the adsorption tower performing the adsorption capacity regeneration process can be heated to a sufficiently high temperature is currently long. For this reason, it is difficult to further shorten the time required for the adsorption capacity regeneration process, and it is preferable to improve this point.

[0012] Furthermore, in the removal system disclosed by the applicant, the amount of heat absorbed from the hydrogen gas by cooling the hydrogen gas containing moisture removed from the adsorbent tends to be smaller than the amount of heat added to the hydrogen gas to heat the hydrogen gas to be flowed into the adsorption tower where the adsorption capacity regeneration process is performed, by the amount of heat lost due to the desorption of moisture from the adsorbent. Therefore, in the removal system disclosed by the applicant, the hydrogen gas to be flowed into the adsorption tower where the adsorption removal process is performed is cooled before being flowed into the adsorption tower, so that the heat absorbed from the hydrogen gas is absorbed in the evaporator, and the amount of heat released in the condenser and the amount of heat absorbed in the evaporator are balanced, making it possible to perform the adsorption removal process and the adsorption capacity regeneration process in parallel.

[0013] Therefore, in the removal system disclosed by the applicant, it is difficult to perform the adsorption capacity regeneration process without cooling the hydrogen gas to be introduced into the adsorption tower where the adsorption removal process is performed before the hydrogen gas is introduced into the adsorption tower, i.e., it is difficult to perform only the adsorption capacity regeneration process alone without performing the adsorption removal process. Therefore, it is preferable to improve this point as well.

[0014] The present invention has been made in consideration of the above-mentioned problems that need to be improved, and has as its main object to provide an adsorbent regeneration device and removal system that can perform adsorption capacity regeneration treatment without performing adsorption removal treatment, and can sufficiently shorten the time required for the adsorption capacity regeneration treatment. [Means for solving the problem]

[0015] In order to achieve the above object, the adsorbent regeneration device according to claim 1 is an adsorbent regeneration device configured to regenerate an adsorbent by an adsorption capacity regeneration process of a heating regeneration type in a removal system capable of performing an adsorption removal process in which a target substance contained in a gas is adsorbed to an adsorbent in an adsorption tower and removed from the gas, the adsorbent regeneration device comprising: a first heat exchanger that heats the gas that is caused to flow into the adsorption tower that performs the adsorption capacity regeneration process by heat exchange with a refrigerant; a second heat exchanger that cools the gas that has been passed through the adsorption tower that performs the adsorption capacity regeneration process by heat exchange with the refrigerant; a refrigeration cycle including a refrigerant supplying refrigerant that has been heat exchanged with the gas in the second heat exchanger to the first heat exchanger, a compressor that pressurizes the refrigerant to the first heat exchanger, and an expansion valve disposed between the first heat exchanger and the second heat exchanger; a separation device that separates the object to be removed from the gas that has been passed through the second heat exchanger; a first blower that blows the gas so that the gas passes through the first heat exchanger, the adsorption tower, the second heat exchanger, and the separation device in this order and flows back into the first heat exchanger; and any one of a gas introduction pipe and a gas discharge pipe. a first flow path switching unit that selectively connects either one of the gas introduction pipe and the gas discharge pipe and the second heat exchanger to one of a pair of gas inlets and outlets in the adsorption tower, a second flow path switching unit that selectively connects either the other of the gas introduction pipe and the gas discharge pipe and the second heat exchanger to the other of the pair of gas inlets and outlets, and a control unit that controls operations of the refrigeration cycle, the first blower, the first flow path switching unit, and the second flow path switching unit, a flow path switching unit for connecting the first heat exchanger to one of the pair of gas inlets and outlets, a second flow path switching unit for connecting the second heat exchanger to the other of the pair of gas inlets and outlets, a first blower for blowing the gas at a predetermined first blowing capacity, and a refrigeration cycle for heating the gas in the first heat exchanger and cooling the gas in the second heat exchanger, when a predetermined first condition is satisfied during the adsorption capacity regeneration process,The first blower is controlled to blow the gas at a predetermined second blowing capacity lower than the first blowing capacity.

[0016] The adsorbent regeneration apparatus of claim 2 is the adsorbent regeneration apparatus of claim 1, further comprising a bypass pipe that allows the gas that has passed through the separation device to flow into the adsorption tower without passing through the first heat exchanger, and a flow rate adjustment unit that adjusts a first flow rate of the gas that passes from the separation device through the first heat exchanger and flows into the adsorption tower and a second flow rate of the gas that passes from the separation device through the bypass pipe and flows into the adsorption tower, and the control unit causes the flow rate adjustment unit to adjust the flow rate of the gas so that the first flow rate is greater than the second flow rate during an adsorption capacity regeneration process until a predetermined second condition for terminating the adsorption capacity regeneration process is satisfied, and causes the flow rate adjustment unit to adjust the flow rate of the gas so that the second flow rate is greater than the first flow rate when the second condition is satisfied.

[0017] The adsorbent regeneration device of claim 3 is the adsorbent regeneration device of claim 2, wherein the refrigeration cycle includes a condenser that condenses the refrigerant and a second blower that blows atmospheric air to the condenser, and the control unit controls the second blower to increase the amount of the atmospheric air blown when the second condition is satisfied.

[0018] The adsorbent regeneration device of claim 4 is the adsorbent regeneration device of claim 1, which is configured to be capable of regenerating the adsorption capacity of the adsorbent in the removal system configured to be capable of removing moisture, which is the target of removal, from hydrogen gas, which is the gas.

[0019] A removal system according to a fifth aspect of the present invention includes the adsorbent regenerating device according to any one of the first to fourth aspects and the adsorption tower, and is configured to be capable of removing the removal target from the gas.

[0020] The removal system of claim 6 is the removal system of claim 5, further comprising a plurality of the adsorption towers, and is configured to be able to execute the adsorption removal process for a portion of each of the adsorption towers and the adsorption capacity regeneration process for another portion of each of the adsorption towers, and when the adsorption removal process for the portion of each of the adsorption towers and the adsorption capacity regeneration process for the other portion of each of the adsorption towers are executed in parallel, the control unit controls the first flow path switching unit to connect one of the pair of gas inlet / outlets in each of the portions of the adsorption towers to one of the gas introduction piping and the gas discharge piping and to connect the first heat exchanger to one of the pair of gas inlet / outlets in the other portion of each of the adsorption towers, and controls the second flow path switching unit to connect the other of the pair of gas inlet / outlets in each of the portions of the adsorption towers to the other of the gas introduction piping and the gas discharge piping and to connect the second heat exchanger to the other of the pair of gas inlet / outlets in the other portion of each of the adsorption towers. Effect of the Invention

[0021] In the adsorbent regeneration device of claim 1, when the control unit starts the adsorption capacity regeneration process, the control unit controls the first flow path switching unit to connect the first heat exchanger to one of a pair of gas inlets and outlets in the adsorption tower, controls the second flow path switching unit to connect the second heat exchanger to the other of the pair of gas inlets and outlets in the adsorption tower, controls the first blower to blow the gas at a predetermined first blowing capacity, and controls the refrigeration cycle to heat the gas in the first heat exchanger and cool the gas in the second heat exchanger, and when the predetermined first condition is satisfied during the adsorption capacity regeneration process, controls the first blower to blow the gas at a predetermined second blowing capacity lower than the first blowing capacity. In addition, the removal system of claim 5 is configured to be capable of removing the removal target from the gas by including the adsorbent regeneration device and the adsorption tower.

[0022] Therefore, according to the adsorbent regeneration device of claim 1 and the removal system of claim 5, even if it is difficult to sufficiently heat the gas by the first heat exchanger immediately after the start of the adsorption capacity regeneration process, the temperature of the gas rises when the first blower blows air at the first blowing capacity, so that the gas with a sufficiently increased temperature can be flowed into the adsorption tower performing the adsorption capacity regeneration process without using an external heat source such as an electric heater. As a result, the adsorbent can be heated immediately after the start of the adsorption capacity regeneration process to remove the removal target, so that the time required for the recovery (regeneration) of the adsorption capacity can be shortened, and the temperature of the gas that is passed through the adsorption tower and reaches the second heat exchanger also rises in a short time, so that a sufficient amount of refrigerant can be vaporized in the second heat exchanger, and the amount of refrigerant circulating per unit time in the refrigerant flow path can be increased in a short time. As a result, the time required for the gas to be in a state where it can be sufficiently heated in the first heat exchanger can be shortened, and the time required for the recovery (regeneration) of the adsorption capacity can be further shortened. In addition, it is possible to carry out only the adsorption capacity regeneration process without carrying out the adsorption removal process, which allows the removal system to be operated in various operating modes.

[0023] In addition, in the adsorbent regeneration device described in claim 2, the control unit controls the flow rate adjustment unit to adjust the gas flow rate so that the first flow rate passing through the first heat exchanger is greater than the second flow rate passing through the bypass piping until a predetermined second condition for terminating the adsorption capacity regeneration process is satisfied, and controls the flow rate adjustment unit to adjust the gas flow rate so that the second flow rate is greater than the first flow rate when the second condition is satisfied.

[0024] Therefore, according to the adsorbent regeneration device and the removal system including such an adsorbent regeneration device, when the adsorption capacity regeneration process is terminated, the amount of gas heated by the first heat exchanger flowing into the adsorption tower is reduced, so that the temperature of the adsorption tower (adsorbent) whose temperature has increased due to the adsorption capacity regeneration process can be reduced in a short time. As a result, even if the adsorption removal process is immediately started using the adsorption tower that has completed the adsorption capacity regeneration process, the adsorbent in the adsorption tower can suitably adsorb the removal target.

[0025] In the adsorbent regeneration device according to claim 3, the control unit controls the second blower to increase the amount of air sent to the condenser when the second condition is satisfied. Therefore, according to the adsorbent regeneration device according to claim 3 and a removal system including such an adsorbent regeneration device, even in a state in which heat exchange with the gas in the first heat exchanger is not performed and the refrigerant is not condensed in the first heat exchanger, a sufficient amount of refrigerant can be condensed in the condenser, and thus the gas can be sufficiently cooled in the second heat exchanger. Therefore, the temperature of the gas flowing from the second heat exchanger through the bypass pipe into the adsorption tower can be sufficiently lowered, and the temperature of the adsorption tower (adsorbent) whose temperature has increased due to the adsorption capacity regeneration process can be lowered in an even shorter time.

[0026] The adsorbent regenerating device according to claim 4 is configured to be capable of regenerating the adsorption capacity of the adsorbent in a removal system configured to be able to remove moisture, which is a target for removal, from hydrogen gas, which is a gas. Therefore, the adsorbent regenerating device according to claim 4 and a removal system including such an adsorbent regenerating device can sufficiently shorten the time required for the adsorption capacity regeneration process of the adsorption tower and reduce the cost, and therefore the time required for removing moisture from hydrogen gas can be sufficiently shortened and the cost can be reduced.

[0027] In the removal system of claim 6, when the control unit performs an adsorption removal process for a part of each adsorption tower and an adsorption capacity regeneration process for the other part of each adsorption tower in parallel, the control unit controls the first flow path switching unit to connect one of the pair of gas inlets and outlets in each part of the adsorption tower to one of the gas introduction pipe and the gas discharge pipe and to connect a first heat exchanger to one of the pair of gas inlets and outlets in the other part of each adsorption tower, and controls the second flow path switching unit to connect the other of the pair of gas inlets and outlets in each part of the adsorption tower to the other of the gas introduction pipe and the gas discharge pipe and to connect a second heat exchanger to the other of the pair of gas inlets and outlets in the other part of each adsorption tower. Thus, according to the removal system of claim 6, the adsorption removal process can be continuously performed by alternately using multiple adsorption towers. [Brief description of the drawings]

[0028] [Figure 1] FIG. 2 is a configuration diagram of the removal system 1 in a state in which an adsorption removal process is being performed on an adsorption tower 2a, and an adsorption capacity regeneration process is being performed on an adsorption tower 2b. [Diagram 2] FIG. 1 is a configuration diagram of the removal system 1 in a state in which an adsorption removal process is being performed on the adsorption tower 2b, and an adsorption capacity regeneration process is being performed on the adsorption tower 2a. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an adsorbent regeneration device and a removal system will be described with reference to the accompanying drawings.

[0030] First, the configuration of the removal system 1 will be described with reference to the accompanying drawings.

[0031] The removal system 1 shown in FIGS. 1 and 2 is an example of a “removal system” and includes adsorption towers 2 a and 2 b and a regeneration device 3 .

[0032] As will be described later, this removal system 1 is configured to perform an adsorption and removal process in which the treatment target is hydrogen gas (an example of a "gas") introduced from a hydrogen gas supply source (not shown) such as a hydrogen generation device or a hydrogen storage tank via an inlet pipe Pi (an example of a "gas introduction pipe"), and moisture contained in this hydrogen gas (an example of a "removal target") is adsorbed by an adsorbent in the adsorption towers 2a, 2b to remove it from the hydrogen gas (reducing the humidity of the hydrogen gas), and the moisture-removed hydrogen gas is supplied (discharged) via a discharge pipe Po (an example of a "gas discharge pipe") to a hydrogen gas supply target (not shown) such as various hydrogen gas-using devices or a hydrogen storage tank different from the above-mentioned hydrogen storage tank.

[0033] In addition, the removal system 1 is configured to be able to regenerate the adsorbent in the adsorption towers 2a, 2b (restore the adsorption capacity to adsorb moisture) through an adsorption capacity regeneration process using a thermal regeneration method (one example of a configuration "configured to be equipped with multiple adsorption towers and to be able to perform an adsorption removal process targeting a part of each adsorption tower and an adsorption capacity regeneration process targeting another part of each adsorption tower").

[0034] The adsorption towers 2a and 2b (hereinafter, when there is no need to distinguish between them, they may be simply referred to as "adsorption tower 2"), which is an example of an "adsorption tower", and is composed of a pressure-resistant container provided with two inlets and outlets (an example of a "pair of gas inlets and outlets") through which hydrogen gas can be introduced / discharged, and a layer of adsorbent through which hydrogen gas can pass is provided between the inlets and outlets. In this case, in the removal system 1 of this example which adsorbs and removes moisture as a "removal target" from hydrogen gas as a "gas", the adsorption tower 2 is composed of an adsorbent such as zeolite (synthetic zeolite) housed in a pressure-resistant container.

[0035] The regeneration device 3 is an example of an "adsorbent regeneration device" and includes a refrigeration cycle 10, a blower 11, a gas-liquid separation tank 12, flow path switching valves 13a, 13b, flow rate control valves 14a, 14b, a control unit 15, and a bypass pipe Pb. In this case, in the regeneration device 3 of this example, a flow path switching valve 13a is provided at one of two inlets and outlets in the adsorption tower 2, and an introduction pipe Pi is connected to the flow path switching valve 13a, and a flow path switching valve 13b is provided at the other of the two inlets and outlets in the adsorption tower 2, and a discharge pipe Po is connected to the flow path switching valve 13b.

[0036] In addition, in the regenerator 3 of this example, hydrogen gas piping is arranged so as to form a hydrogen gas circulation path in which hydrogen gas flows again into the adsorption tower 2 to be treated, via the adsorption tower 2 to be treated, the flow path switching valve 13a, the heat exchanger 24, the gas-liquid separation tank 12, the blower 11, the flow rate control valve 14a, and the heat exchanger 22, during the adsorption capacity regeneration process. Furthermore, in the regenerator 3 of this example, as will be described later, a bypass piping Pb (an example of a "bypass piping that allows the gas passed through the separation device to flow into the adsorption tower without passing through the first heat exchanger") is provided in parallel so that a part or all of the hydrogen gas blown by the blower 11 flows into the adsorption tower 2 from the flow path switching valve 13b without passing through the flow rate control valve 14a and the heat exchanger 22.

[0037] Immediately after the installation of the removal system 1 is completed, or when all hydrogen gas has been removed from the system during various maintenance work, no hydrogen gas is present in the hydrogen gas piping (including the bypass piping Pb) that constitutes the hydrogen gas circulation path. Therefore, when the adsorption capacity regeneration process is started, it is necessary to fill the hydrogen gas piping (including the bypass piping Pb) that constitutes the hydrogen gas circulation path with hydrogen gas. However, since the process of degassing the air and filling the piping with hydrogen gas is well known, a description of this filling process will be omitted.

[0038] The refrigeration cycle 10 is an example of a "refrigeration cycle" and includes a compressor 21, a heat exchanger 22, an expansion valve 23, a heat exchanger 24, a condenser 25, and a fan 25a. In this case, the heat exchanger 22 is an example of a "first heat exchanger" and is arranged to function as a "condenser" in the refrigeration cycle 10, and is configured to be able to heat the hydrogen gas that is to be flowed into the adsorption tower 2 that performs the adsorption capacity regeneration process, as described below, by heat exchange with the refrigerant. The heat exchanger 24 is an example of a "second heat exchanger" and is arranged to function as an "evaporator" in the refrigeration cycle 10, and is configured to be able to cool the hydrogen gas that has been passed through the adsorption tower 2 that performs the adsorption capacity regeneration process by heat exchange with the refrigerant.

[0039] The condenser 25 is an example of a "condenser" and is arranged so that when the amount of refrigerant condensed in the heat exchanger 22 becomes insufficient as described below, the condenser 25 can condense a necessary amount of refrigerant. The location of the condenser 25 in the refrigeration cycle 10 is not limited to the downstream side of the heat exchanger 22 (first heat exchanger) as shown in both figures, and the condenser 25 can also be arranged between the compressor 21 and the heat exchanger 22 (upstream side of the heat exchanger 22). The fan 25a is an example of a "second blower" and blows air to the condenser 25 under the control of the control unit 15 when the necessary amount of refrigerant is condensed in the condenser 25 as described above.

[0040] The blower 11 is an example of a "first blower" and blows hydrogen gas so that the hydrogen gas passes through the heat exchanger 22, the adsorption tower 2, the heat exchanger 24, and the gas-liquid separation tank 12 in this order and flows back into the heat exchanger 22. The arrangement of the blower 11 in the hydrogen gas circulation path is not limited to between the gas-liquid separation tank 12 and the heat exchanger 22 (first heat exchanger) as shown in both figures, but may be arranged between the heat exchanger 22 and the bypass pipe Pb and the flow path switching valve 13b, between the flow path switching valve 13a and the heat exchanger 24, and between the heat exchanger 24 and the gas-liquid separation tank 12. The gas-liquid separation tank 12 is an example of a "separation device" and separates moisture from the hydrogen gas passed through the heat exchanger 24.

[0041] The flow path switching valve 13a is an example of a "second flow path switching unit" and selectively connects either the introduction pipe Pi or the heat exchanger 24 to one of two gas inlets and outlets in the adsorption tower 2 under the control of the control unit 15 (an example of a configuration in which the "other of the gas introduction pipe and the gas exhaust pipe" is the "gas introduction pipe"). The flow path switching valve 13b is an example of a "first flow path switching unit" and selectively connects either the exhaust pipe Po or the heat exchanger 22 to one of two gas inlets and outlets in the adsorption tower 2 under the control of the control unit 15 (an example of a configuration in which the "either the gas introduction pipe or the gas exhaust pipe" is the "gas exhaust pipe").

[0042] The flow rate control valves 14a and 14b are an example of a "flow rate control unit", and under the control of the control unit 15, the flow rate control valve 14a adjusts the flow rate of hydrogen gas passing from the gas-liquid separation tank 12 through the heat exchanger 22 and flowing into the adsorption tower 2 (an example of a "first flow rate"), and the flow rate control valve 14b adjusts the flow rate of hydrogen gas passing from the gas-liquid separation tank 12 through the bypass piping Pb and flowing into the adsorption tower 2 (a flow rate of hydrogen gas flowing into the adsorption tower 2 without passing through the heat exchanger 22: an example of a "second flow rate"). Note that, instead of the above-mentioned flow rate control valves 14a and 14b, the "flow rate control unit" may be configured to selectively pass hydrogen gas through either the heat exchanger 22 or the bypass piping Pb by providing a three-way valve at either the upstream end or the downstream end of the bypass piping Pb.

[0043] The control unit 15 is an example of a "control unit" and controls the removal system 1 (regeneration device 3) in an overall manner. Specifically, the control unit 15 controls the flow path switching valves 13a and 13b to switch the flow path of hydrogen gas, controls the blower 11 to blow (pressure-feed) hydrogen gas, and controls the flow rate adjustment valves 14a and 14b to adjust the flow rate of hydrogen gas passing through the heat exchanger 22 and the bypass pipe Pb. The control unit 15 also controls the refrigeration cycle 10 to heat the hydrogen gas in the heat exchanger 22, cool the hydrogen gas in the heat exchanger 24, and condense the refrigerant in the condenser 25 (blow air by the fan 25a). The manner in which the control unit 15 controls each unit will be described in detail later with specific examples.

[0044] Next, the adsorption removal process and the adsorption capacity regeneration process performed by the removal system 1 will be described.

[0045] In the present embodiment, the removal system 1 is configured to be capable of operating in an operating mode in which the adsorption removal process and the adsorption capacity regeneration process are performed in parallel, as well as in an operating mode in which only the adsorption removal process is performed independently, and in an operating mode in which only the adsorption capacity regeneration process is performed independently.

[0046] First, when only the adsorption removal process is performed alone, the control unit 15 controls the flow path switching valves 13a, 13b while the refrigeration cycle 10 and the blower 11 are stopped, to switch between a state in which hydrogen gas introduced via the inlet pipe Pi passes through the adsorption tower 2a and is discharged via the discharge pipe Po (the state shown in FIG. 1), and a state in which hydrogen gas introduced via the inlet pipe Pi passes through the adsorption tower 2b and is discharged via the discharge pipe Po (the state shown in FIG. 2).

[0047] In this case, as shown in Fig. 1, when the adsorption tower 2a is connected to the inlet pipe Pi and the outlet pipe Po by the flow path switching valves 13a, 13b, hydrogen gas introduced via the inlet pipe Pi is passed through the adsorption tower 2a and discharged from the outlet pipe Po, as shown by arrow Aa in the figure. At this time, moisture contained in the introduced hydrogen gas is adsorbed by the adsorbent in the adsorption tower 2a and removed. Note that Fig. 1 and Fig. 2 show a state in which the ports shown in black among the four ports of the flow path switching valves 13a, 13b are communicated with each other, and the ports shown in white are communicated with each other.

[0048] Also, as shown in FIG. 2, when the adsorption tower 2b is connected to the inlet pipe Pi and the outlet pipe Po by the flow path switching valves 13a and 13b, the hydrogen gas introduced through the inlet pipe Pi is passed through the adsorption tower 2b and discharged from the outlet pipe Po, as shown by the arrow Ab in the figure. At this time, the moisture contained in the introduced hydrogen gas is adsorbed and removed by the adsorbent in the adsorption tower 2b. As a result, the hydrogen gas from which the moisture has been removed is supplied to the hydrogen gas supply target. In this case, in either of the above states, the adsorption capacity of the adsorbent in the adsorption tower 2 gradually decreases due to the adsorption of the moisture contained in the hydrogen gas. Therefore, it is necessary to perform an adsorption capacity regeneration process to regenerate the adsorption capacity before the adsorption capacity of the adsorbent decreases to a level at which it is difficult to suitably remove moisture from the hydrogen gas to be treated in the adsorption tower 2.

[0049] On the other hand, when the adsorption capacity regeneration process is performed alone, the control unit 15 controls the refrigeration cycle 10 to start the circulation of the refrigerant in the refrigerant flow path. The control unit 15 also controls the flow path switching valves 13a and 13b to switch the flow path so that hydrogen gas circulates in the hydrogen gas circulation path. The control unit 15 also controls the blower 11 to start the circulation of hydrogen gas in the hydrogen gas circulation path. At this point in time when the adsorption capacity regeneration process is started, the control unit 15, for example, controls the flow rate adjustment valve 14a to an open state and controls the flow rate adjustment valve 14b to a closed state, so that all of the hydrogen gas blown by the blower 11 passes through the heat exchanger 22 without passing through the bypass pipe Pb (an example of control in which "the flow rate adjustment unit adjusts the gas flow rate so that the first flow rate is greater than the second flow rate until a second condition that is specified in advance for terminating the adsorption capacity regeneration process is satisfied"). The control unit 15 also maintains the fan 25a in a stopped state (a state in which the amount of refrigerant condensed in the condenser 25 is the smallest).

[0050] In this case, when the adsorption capacity regeneration process for the adsorption tower 2b is started, the control unit 15 controls the flow path switching valve 13a to connect the heat exchanger 24 to one of the two inlets and outlets in the adsorption tower 2b (an example of the control of "controlling the second flow path switching unit to connect the second heat exchanger to the other of the pair of gas inlets and outlets") and controls the flow path switching valve 13b to connect the heat exchanger 22 to the other of the two inlets and outlets in the adsorption tower 2b (an example of the control of "controlling the first flow path switching unit to connect the first heat exchanger to one of the pair of gas inlets and outlets"). At this time, as shown by the arrow Ba in the figure, the hydrogen gas blown by the blower 11 passes through the flow rate control valve 14a, the heat exchanger 22, the flow path switching valve 13b, the adsorption tower 2b, the flow path switching valve 13a, the heat exchanger 24, and the gas-liquid separation tank 12 in this order, and is blown again by the blower 11 toward the heat exchanger 22.

[0051] Furthermore, when starting the adsorption capacity regeneration process for the adsorption tower 2a, the control unit 15 controls the flow path switching valve 13a to connect the heat exchanger 24 to one of the two inlets and outlets in the adsorption tower 2a, as shown in FIG. 2 (another example of the control of "controlling the second flow path switching unit to connect the second heat exchanger to the other of the pair of gas inlets and outlets"), and controls the flow path switching valve 13b to connect the heat exchanger 22 to the other of the two inlets and outlets in the adsorption tower 2a (another example of the control of "controlling the first flow path switching unit to connect the first heat exchanger to one of the pair of gas inlets and outlets"). At this time, as shown by arrow Bb in the figure, the hydrogen gas blown by blower 11 passes through flow control valve 14a, heat exchanger 22, flow path switching valve 13b, adsorption tower 2a, flow path switching valve 13a, heat exchanger 24 and gas-liquid separation tank 12 in that order, and is again blown by blower 11 toward heat exchanger 22.

[0052] As a result, hydrogen gas (hydrogen gas with reduced relative humidity) heated by heat exchange with the refrigerant in the heat exchanger 22 is caused to flow into the adsorption tower 2, and the adsorbent in the adsorption tower 2 is heated by this hydrogen gas. In addition, as the temperature of the adsorbent rises, the adsorbed moisture is desorbed (vaporized) from the adsorbent and discharged from the adsorption tower 2 together with the hydrogen gas. Furthermore, the hydrogen gas discharged from the adsorption tower 2 is cooled by heat exchange with the refrigerant in the heat exchanger 24, so that the relative humidity rises and the moisture in the gas phase changes to a liquid phase. In addition, the moisture (water droplets) and hydrogen gas in the liquid phase discharged from the heat exchanger 24 are separated into gas and liquid in the gas-liquid separation tank 12, and the moisture in the liquid phase is stored in the gas-liquid separation tank 12, while the hydrogen gas from which the moisture has been separated is blown again by the blower 11 toward the heat exchanger 22. As a result, by continuing this adsorption capacity regeneration process, the adsorbent in the adsorption tower 2 is regenerated and the adsorption capacity is restored. The moisture separated in gas-liquid separation tank 12 is, for example, discharged from gas-liquid separation tank 12 when the amount of water stored in gas-liquid separation tank 12 reaches a specified amount.

[0053] In this case, immediately after the start of the adsorption capacity regeneration process, that is, immediately after the circulation of the refrigerant in the refrigerant flow passage of the refrigeration cycle 10 is started, the temperature of the refrigerant compressed by the compressor 21 and pumped to the heat exchanger 22 has not risen to a sufficiently high temperature. For this reason, it is difficult to raise the temperature of the hydrogen gas to be flowed into the adsorption tower 2 to a sufficiently high temperature in the heat exchanger 22. In addition, since the temperature of the hydrogen gas passing through the adsorption tower 2 and flowing into the heat exchanger 24 has not risen to a sufficiently high temperature, it is also difficult to vaporize a sufficient amount of refrigerant in the heat exchanger 24. As a result, since the compressor 21 cannot compress a sufficient amount of refrigerant and supply it to the heat exchanger 22, it takes a long time until the heat exchanger 22 is in a state where the hydrogen gas can be heated to a sufficiently high temperature.

[0054] Therefore, in the removal system 1 (regeneration device 3) of this example, at the start of the adsorption capacity regeneration process, the control unit 15 controls the blower 11 to blow hydrogen gas at the highest blowing capacity (the highest blowing capacity among the blowing capacities of the blower 11 that can be changed during the operation of the removal system 1: as an example, operation at the rated capacity of the motor used for the blower 11: an example of a "predetermined first blowing capacity"). At this time, the power source (motor) of the blower 11 is rotated at high speed to increase the heat generation amount of the blower 11, and the hydrogen gas blown by the blower 11 is overheated (temperature increased) by this heat. Therefore, even though it is difficult to sufficiently heat the hydrogen gas in the heat exchanger 22 immediately after the start of the adsorption capacity regeneration process as described above, the temperature of the hydrogen gas to be flowed into the adsorption tower 2 can be increased by the amount of the increase in the temperature of the hydrogen gas blown by the blower 11 operating at the "first blowing capacity". This makes it possible to sufficiently increase the temperature of the adsorbent in the adsorption tower 2 to be treated in a short period of time.

[0055] In addition, by making the blower 11 blow hydrogen gas at the "first blowing capacity" to raise the temperature of the hydrogen gas flowing into the adsorption tower 2, the temperature of the hydrogen gas discharged from the adsorption tower 2 also rises in a short time, compared to when the blower 11 is operated at a low blowing capacity (a state in which the amount of heat generated by the blower 11 is small). This makes it possible to vaporize a sufficient amount of refrigerant in the heat exchanger 24, and to compress a sufficient amount of refrigerant by the compressor 21 and supply it to the heat exchanger 22. Therefore, it is possible to shorten the time required for the refrigeration cycle 10 to reach a state in which the hydrogen gas can be heated to a sufficiently high temperature in the heat exchanger 22, and it is possible to raise the temperature of the hydrogen gas flowing into the adsorption tower 2 in a short time. As a result, it is possible to sufficiently raise the temperature of the adsorbent in the adsorption tower 2 to be treated in a short time.

[0056] In addition, as an example, when a predetermined time has elapsed since the start of the adsorption capacity regeneration process (an example of "when a first condition is satisfied during the execution of the adsorption capacity regeneration process"), the control unit 15 controls the blower 11 to blow hydrogen gas at a "second blowing capacity" that is lower than the above-mentioned "first blowing capacity". In this case, the temperature of the hydrogen gas blown by the blower 11 at the "first blowing capacity" increases, so that a sufficient amount of refrigerant is circulated in the refrigerant flow path to sufficiently heat the hydrogen gas in the heat exchanger 22. Therefore, when such a state is reached, high-temperature hydrogen gas can be introduced into the adsorption tower 2 without increasing the temperature of the hydrogen gas in the blower 11. Therefore, in the removal system 1 of this example, a configuration is adopted in which the blowing capacity of the blower 11 is reduced (shifted to blowing at the "second blowing capacity") when the "first condition" is satisfied in order to reduce the power consumption of the blower 11.

[0057] The above-mentioned "predetermined time" refers to the time required for the circulation amount of the refrigerant per unit time in the refrigeration cycle 10 to reach a sufficient amount and for the hydrogen gas to be heated to a sufficiently high temperature in the heat exchanger 22. Therefore, for the "first condition", instead of the above-mentioned condition "when a predetermined time has elapsed since the start of the adsorption capacity regeneration process", a condition such as "when the temperature of the hydrogen gas flowing into the adsorption tower 2 has risen to a predetermined temperature (a temperature at which the adsorbent can be heated to a temperature sufficient to desorb moisture)" or "when the temperature of the heat exchanger 22 has risen to a predetermined temperature (a temperature at which the hydrogen gas can be sufficiently heated)" can also be adopted.

[0058] On the other hand, by continuing the adsorption capacity regeneration process, a sufficient amount of moisture is desorbed from the adsorbent in the adsorption tower 2, and the adsorption capacity of the adsorption tower 2 is sufficiently restored (regenerated). In this case, when the adsorption removal process is immediately performed using the adsorption tower 2 whose adsorption capacity has been restored by the adsorption capacity regeneration process, the temperature of the hydrogen gas (hydrogen gas from which moisture should be removed) flowing into the adsorption tower 2 increases and the relative humidity becomes low (i.e., a state in which moisture is difficult to remove), making it difficult for moisture to be adsorbed by the adsorbent. Therefore, in order to avoid this, it is necessary to sufficiently lower the temperature of the adsorption tower 2 (adsorbent) whose temperature has been increased by the adsorption capacity regeneration process. In addition, when the adsorption capacity regeneration process is continued in a state in which the adsorption capacity of the adsorption tower 2 has been sufficiently restored (regenerated), power consumption by the refrigeration cycle 10 and the blower 11 is wasted.

[0059] Therefore, as an example, when the temperature difference between the temperature of the hydrogen gas flowing into the adsorption tower 2 during regeneration and the temperature of the hydrogen gas discharged from the adsorption tower 2 (the amount of heat lost due to the volatilization of moisture from the adsorbent in the adsorption tower 2 during regeneration) falls below a specified temperature (an example of "when a second condition for terminating the adsorption capacity regeneration process is satisfied"), the control unit 15 controls the flow rate control valve 14a to a closed state and controls the flow rate control valve 14b to an open state, so that all of the hydrogen gas blown by the blower 11 passes through the bypass pipe Pb without passing through the heat exchanger 22 (an example of control of "when the second condition is satisfied, the flow rate control unit adjusts the flow rate of the gas so that the second flow rate is greater than the first flow rate"). In addition, the control unit 15 controls the fan 25a to blow air toward the condenser 25 (an example of control of "when the second condition is satisfied, the second blower is controlled to increase the amount of air blown").

[0060] At this time, hydrogen gas that has not passed through the heat exchanger 22 but has passed through the bypass pipe Pb (i.e., hydrogen gas that has not been heated in the heat exchanger 22) flows into the adsorption tower 2 undergoing the adsorption capacity regeneration process, so that the adsorbent in the adsorption tower 2 is prevented from being further heated. In addition, the fan 25a starts blowing air to the condenser 25 (the amount of air blown to the condenser 25 is increased), so that even in a state in which the refrigerant is not condensed by heat exchange with hydrogen in the heat exchanger 22, a sufficient amount of refrigerant can be condensed by heat exchange with the air in the condenser 25. This allows the refrigeration cycle 10 to continue operating. In addition, the hydrogen gas that flows into the adsorption tower 2 at this time is cooled by heat exchange with the refrigerant in the heat exchanger 24, and then passes through the gas-liquid separation tank 12 and the bypass pipe Pb to flow into the adsorption tower 2, so that its temperature is sufficiently low. Therefore, by flowing such hydrogen gas into the adsorption tower 2, the adsorbent in the adsorption tower 2 is sufficiently cooled in a short time.

[0061] The above condition "when the temperature difference between the temperature of the hydrogen gas flowing into the adsorption tower 2 during regeneration and the temperature of the hydrogen gas discharged from the adsorption tower 2 falls below a specified temperature" is one of the events that is satisfied when the adsorption capacity regeneration process causes moisture to be sufficiently removed from the adsorbent in the adsorption tower 2 and the adsorption capacity of the adsorbent is sufficiently restored (regenerated). Therefore, instead of the above condition, for "when the second condition is satisfied", a condition "when the amount of moisture separated (stored) per unit time in the gas-liquid separation tank 12 (the amount of moisture removed from the adsorbent per unit time) falls below a predetermined moisture amount" or a condition "when the humidity of the hydrogen gas discharged from the adsorption tower 2 during regeneration falls below a predetermined humidity" can also be adopted. In addition, a configuration can be adopted in which the "second condition" is satisfied in the "operating state of the refrigeration cycle 10", which changes depending on the amount of moisture contained in the hydrogen gas discharged from the adsorption tower 2, for example, when "the load applied to the compressor 21 falls below a specified amount" or when "the difference in refrigerant pressure within the refrigeration cycle 10 falls below a specified amount".

[0062] Thereafter, as an example, the control unit 15 determines that the above-mentioned "second condition" is satisfied and controls the flow rate control valve 14a to a closed state, and controls the flow rate control valve 14b to an open state, and then when a predetermined time (the time required for the temperature of the adsorption tower 2 to be sufficiently reduced) has elapsed, stops the refrigeration cycle 10 and the blower 11, and terminates the adsorption capacity regeneration process. Note that at this time, the refrigeration cycle 10 and the blower 11 can also be stopped to terminate the adsorption capacity regeneration process when the temperature of the adsorption tower 2 or the hydrogen gas discharged from the adsorption tower 2 has decreased to a predetermined temperature (i.e., when the adsorbent in the adsorption tower 2 has been sufficiently cooled).

[0063] In this case, in the removal system 1 of this example, which is capable of performing only the adsorption removal process alone without performing the adsorption capacity regeneration process, or performing only the adsorption capacity regeneration process alone without performing the adsorption removal process, the adsorption removal process can be performed alone when, for example, it is desired to refrain from operating the refrigeration cycle 10 or the blower 11, or when the adsorption capacity of the adsorbent due to the adsorption removal process does not decrease in a short period of time (when the flow rate per unit time of the hydrogen gas from which moisture is to be removed is small, or when the amount of moisture contained in the hydrogen gas is small), and the adsorption capacity regeneration process can be performed alone when it is not necessary to remove moisture from the hydrogen gas (for example, when it is not necessary to supply hydrogen gas to the supply target), thereby restoring (regenerating) the adsorption capacity of the adsorption tower 2 (adsorbent) so that the adsorption removal process can be performed later.

[0064] Furthermore, in the removal system 1 of this example, similar to the above-mentioned removal system disclosed by the applicant, the adsorption removal process using one of the adsorption towers 2 and the adsorption capacity regeneration process targeting the other adsorption tower 2 are configured to be able to be performed in parallel.

[0065] Specifically, as an example, when an adsorption removal process for the adsorption tower 2a (an example of "a part of each adsorption tower") and an adsorption capacity regeneration process for the adsorption tower 2b (an example of "the other part of each adsorption tower") are performed in parallel, the control unit 15 controls the flow path switching valve 13a, as shown in FIG. 1, to connect the introduction pipe Pi to one of the two inlets and outlets in the adsorption tower 2a, and to connect a heat exchanger 24 to one of the two inlets and outlets in the adsorption tower 2b (an example of control of "controlling the second flow path switching unit to connect the other of the pair of gas inlets and outlets in the part of each adsorption tower to the other of the gas introduction pipe and the gas exhaust pipe, and to connect a second heat exchanger to the other of the pair of gas inlets and outlets in the other part of each adsorption tower", where the "other pipe" is the "gas introduction pipe"). The control unit 15 also controls the flow path switching valve 13b to connect the discharge pipe Po to the other of the two inlets and outlets in the adsorption tower 2a, and to connect the heat exchanger 22 to the other of the two inlets and outlets in the adsorption tower 2b (an example of control of "controlling the first flow path switching unit to connect one of a pair of gas inlets and outlets in a part of each adsorption tower to either the gas introduction pipe or the gas exhaust pipe, and to connect the first heat exchanger to one of the pair of gas inlets and outlets in the other part of each adsorption tower", in which "one of the pipes" is the "gas exhaust pipe").

[0066] At this time, as shown by arrow Aa in the figure, hydrogen gas introduced through the inlet pipe Pi is passed through the adsorption tower 2a and discharged from the outlet pipe Po, and at that time, moisture contained in the hydrogen gas is adsorbed and removed by the adsorbent in the adsorption tower 2a. Also, as shown by arrow Ba in the figure, hydrogen gas blown by the blower 11 passes through the flow rate control valve 14a, the heat exchanger 22, the flow path switching valve 13b, the adsorption tower 2b, the flow path switching valve 13a, the heat exchanger 24, and the gas-liquid separation tank 12 in this order, and is blown again by the blower 11 toward the heat exchanger 22, and moisture is removed from the adsorbent in the adsorption tower 2b by the hydrogen gas heated by the blower 11 and the heat exchanger 22, and the adsorption capacity of the adsorbent in the adsorption tower 2b is restored (regenerated).

[0067] When the adsorption removal process for the adsorption tower 2b (another example of "a part of each adsorption tower") and the adsorption capacity regeneration process for the adsorption tower 2a (another example of "the other part of each adsorption tower") are performed in parallel, the control unit 15 controls the flow path switching valve 13a, as shown in FIG. 2, to connect the introduction pipe Pi to one of the two inlets and outlets in the adsorption tower 2b, and to connect the heat exchanger 24 to one of the two inlets and outlets in the adsorption tower 2a (another example of the control of "controlling the second flow path switching unit to connect the other of the pair of gas inlets and outlets in the part of each adsorption tower to the other of the gas introduction pipe and the gas discharge pipe, and to connect the second heat exchanger to the other of the pair of gas inlets and outlets in the other part of each adsorption tower", where the "other pipe" is the "gas introduction pipe"). The control unit 15 also controls the flow path switching valve 13b to connect the discharge pipe Po to the other of the two inlets and outlets in the adsorption tower 2b, and to connect the heat exchanger 22 to the other of the two inlets and outlets in the adsorption tower 2a (another example of the control of "controlling the first flow path switching unit to connect one of a pair of gas inlets and outlets in a part of each adsorption tower to either the gas introduction pipe or the gas exhaust pipe, and to connect the first heat exchanger to one of the pair of gas inlets and outlets in the other part of each adsorption tower", in which "one of the pipes" is the "gas exhaust pipe").

[0068] At this time, as shown by arrow Ab in the figure, hydrogen gas introduced through the inlet pipe Pi is passed through the adsorption tower 2b and discharged from the outlet pipe Po, and at that time, moisture contained in the hydrogen gas is adsorbed and removed by the adsorbent in the adsorption tower 2b. Also, as shown by arrow Bb in the figure, hydrogen gas blown by the blower 11 passes through the flow rate control valve 14a, the heat exchanger 22, the flow path switching valve 13b, the adsorption tower 2a, the flow path switching valve 13a, the heat exchanger 24, and the gas-liquid separation tank 12 in this order, and is blown again toward the heat exchanger 22 by the blower 11, and moisture is removed from the adsorbent in the adsorption tower 2a by the hydrogen gas heated by the blower 11 and the heat exchanger 22, and the adsorption capacity of the adsorbent in the adsorption tower 2b is restored (regenerated).

[0069] Therefore, in the removal system 1 of this embodiment, by alternately switching between the states shown in FIGS. 1 and 2, it is possible to continuously perform the adsorption and removal process using both adsorption towers 2a and 2b.

[0070] Thus, in this regeneration device 3, when the adsorption capacity regeneration process is started, the control unit 15 controls the flow path switching valve 13b to connect the heat exchanger 22 to one of the pair of hydrogen gas inlets and outlets in the adsorption tower 2, controls the flow path switching valve 13a to connect the heat exchanger 24 to the other of the pair of hydrogen gas inlets and outlets in the adsorption tower 2, controls the blower 11 to blow hydrogen gas at a predetermined "first blowing capacity", and controls the refrigeration cycle 10 to heat the hydrogen gas in the heat exchanger 22 and cool the hydrogen gas in the heat exchanger 24. When the predetermined "first condition" is satisfied during the adsorption capacity regeneration process, the blower 11 is controlled to blow hydrogen gas at a predetermined "second blowing capacity" lower than the "first blowing capacity". In addition, the removal system 1 is configured to be capable of removing moisture from hydrogen gas by including the regeneration device 3 and the adsorption tower 2.

[0071] Therefore, according to the regeneration device 3 and the removal system 1, even if it is difficult to sufficiently heat the hydrogen gas by the heat exchanger 22 immediately after the start of the adsorption capacity regeneration process, the temperature of the hydrogen gas rises when the blower 11 blows air at the "first blowing capacity", so that hydrogen gas with a sufficiently increased temperature can be flowed into the adsorption tower 2 performing the adsorption capacity regeneration process without using an external heat source such as an electric heater. As a result, the adsorbent can be heated and moisture can be removed immediately after the start of the adsorption capacity regeneration process, so that the time required for the recovery (regeneration) of the adsorption capacity can be shortened, and the temperature of the hydrogen gas that is passed through the adsorption tower 2 and reaches the heat exchanger 24 also rises in a short time, so that a sufficient amount of refrigerant can be vaporized in the heat exchanger 24, and the amount of refrigerant circulating per unit time in the refrigerant flow path can be increased in a short time. As a result, the time required for the heat exchanger 22 to reach a state where hydrogen gas can be sufficiently heated can be shortened, and the time required for the recovery (regeneration) of the adsorption capacity can be further shortened. In addition, it is possible to execute only the adsorption capacity regeneration process without executing the adsorption removal process, thereby allowing the removal system 1 to operate in various modes.

[0072] Furthermore, in the regeneration device 3, the control unit 15 controls the flow control valves 14a, 14b to adjust the flow rate of hydrogen gas passing through the heat exchanger 22 so that the "first flow rate" passing through the bypass pipe Pb is greater than the "second flow rate" until a predetermined "second condition" for terminating the adsorption capacity regeneration process is satisfied, and controls the flow control valves 14a, 14b to adjust the flow rate of hydrogen gas so that the "second flow rate" is greater than the "first flow rate" when the "second condition" is satisfied.

[0073] Therefore, according to the regeneration device 3 and removal system 1, when the adsorption capacity regeneration process is terminated, the amount of hydrogen gas heated by the heat exchanger 22 flowing into the adsorption tower 2 is reduced (in this example, hydrogen gas heated by the heat exchanger 22 is prevented from flowing into the adsorption tower 2), thereby making it possible to quickly lower the temperature of the adsorption tower 2 (adsorbent) whose temperature has increased due to the adsorption capacity regeneration process. As a result, even if the adsorption removal process is immediately started using the adsorption tower 2 that has completed the adsorption capacity regeneration process, moisture can be suitably adsorbed by the adsorbent in the adsorption tower 2.

[0074] Furthermore, in this regeneration device 3, when the "second condition" is satisfied, the control unit 15 controls the fan 25a to increase the amount of air blown to the condenser 25. Therefore, according to this regeneration device 3 and removal system 1, even in a state in which heat exchange with hydrogen gas is not performed in the heat exchanger 22 and the refrigerant is not condensed in the heat exchanger 22, a sufficient amount of refrigerant can be condensed in the condenser 25, and thus the hydrogen gas can be sufficiently cooled in the heat exchanger 24. Therefore, the temperature of the hydrogen gas flowing from the heat exchanger 24 through the bypass pipe Pb into the adsorption tower 2 can be sufficiently lowered, and the temperature of the adsorption tower 2 (adsorbent) whose temperature has been increased by the adsorption capacity regeneration process can be lowered in an even shorter time.

[0075] Furthermore, the regeneration device 3 is configured to be capable of regenerating the adsorption capacity of the adsorbent in the removal system 1, which is configured to be capable of removing moisture as a "subject to removal" from hydrogen gas as a "gas." Therefore, with the regeneration device 3 and the removal system 1, the time required for the adsorption capacity regeneration process of the adsorption tower 2 can be sufficiently shortened and the cost can be reduced, and therefore the time required for removing moisture from hydrogen gas can be sufficiently shortened and the cost can be reduced.

[0076] Furthermore, in this removal system 1, when the control unit 15 performs an adsorption removal process for a part of each adsorption tower 2 and an adsorption capacity regeneration process for the other part of each adsorption tower 2 in parallel, the control unit 15 controls the flow path switching valve 13b to connect one of a pair of hydrogen gas inlets and outlets in the part of each adsorption tower 2 to the discharge pipe Po and to connect a heat exchanger 22 to one of the pair of hydrogen gas inlets and outlets in the other part of each adsorption tower 2, and controls the flow path switching valve 13a to connect the other of the pair of hydrogen gas inlets and outlets in the part of each adsorption tower 2 to the introduction pipe Pi and to connect a heat exchanger 24 to the other of the pair of hydrogen gas inlets and outlets in the other part of each adsorption tower 2. Thus, according to this removal system 1, the adsorption removal process can be continuously performed by alternately using the multiple adsorption towers 2.

[0077] The configurations of the "adsorbent regenerating device" and the "removal system" are not limited to the examples of the configurations of the regenerating device 3 and the removal system 1 described above.

[0078] For example, the configuration including two adsorption towers 2 has been described as an example of the "plurality of adsorption towers," but the "removal system" and its "adsorbent regeneration device" may also be configured with three or more adsorption towers 2. Specifically, when the time required for the adsorbent in the adsorption tower 2 performing the adsorption capacity regeneration process to desorb moisture favorably is longer than the time required for the adsorbent in the adsorption tower 2 performing the adsorption removal process to desorb moisture favorably, as an example, three adsorption towers 2 are provided, and the adsorption removal process is performed in one of them while the adsorption capacity regeneration process is performed in the other two, making it possible to perform the adsorption removal process continuously. Also, when the time required for the adsorbent in the adsorption tower 2 performing the adsorption removal process to desorb moisture favorably is longer than the time required for the adsorbent in the adsorption tower 2 performing the adsorption capacity regeneration process to desorb moisture favorably, as an example, three adsorption towers 2 are provided, and the adsorption capacity regeneration process is performed in one of them while the adsorption removal process is performed in the other two, making it possible to efficiently perform the adsorption removal process and the adsorption capacity removal process.

[0079] In addition, the configuration capable of removing moisture, which is an example of a "removal target", from hydrogen gas, which is an example of a "gas", using zeolite (synthetic zeolite) or the like as an "adsorbent", has been described as an example, but the "gas", "adsorbent", and "removal target" are not limited to this example. For example, the configuration of the present invention can be adopted in a "removal system" that adsorbs and removes moisture, etc., as a "removal target" from "oxygen" as a "gas" using zeolite (synthetic zeolite) or the like as an "adsorbent" and its "adsorbent regeneration device". In addition, the configuration of the present invention can be adopted in a "removal system" that adsorbs and removes volatile organic compounds (VOCs), etc., as a "removal target" from exhaust gas (gas discharged by combustion in an internal combustion engine, etc.), which is a "gas", using activated carbon or the like as an "adsorbent". In addition, the configuration of the present invention can be adopted in a "removal system" that adsorbs and removes moisture, etc., as a "removal target" from the atmosphere (outside air) as a "gas" using zeolite (synthetic zeolite) or the like as an "adsorbent" and its "adsorbent regeneration device". [Explanation of symbols]

[0080] 1. Removal System 2a,2b Adsorption tower 3 Playback device 10 Refrigeration cycle 11 Blower 12 Gas-liquid separation tank 13a, 13b Flow path switching valve 14a, 14b Flow control valve 15 Control section 21 Compressor 22 Heat exchanger 23 Expansion valve 24 Heat exchanger 25 Condenser 25a Fan Pb bypass piping Pi introduction piping Po discharge piping

Claims

1. An adsorbent regeneration device for a removal system capable of performing an adsorption removal process in which a target substance contained in a gas is adsorbed by an adsorbent in an adsorption tower and removed from the gas, the adsorbent being configured to be regenerated by an adsorption capacity regeneration process using a thermal regeneration method, a refrigeration cycle including a first heat exchanger that heats the gas flowing into the adsorption tower that performs the adsorption capacity regeneration treatment by heat exchange with a refrigerant, a second heat exchanger that cools the gas that has passed through the adsorption tower that performs the adsorption capacity regeneration treatment by heat exchange with the refrigerant, a compressor that compresses the refrigerant that has been heat exchanged with the gas in the second heat exchanger to the first heat exchanger, and an expansion valve disposed between the first heat exchanger and the second heat exchanger; A separation device that separates the target to be removed from the gas that has been passed through the second heat exchanger; a first blower configured to blow the gas so that the gas passes through the first heat exchanger, the adsorption tower, the second heat exchanger, and the separation device in this order and then flows back into the first heat exchanger; a first flow path switching unit that selectively connects one of a gas introduction pipe and a gas discharge pipe and the first heat exchanger to one of a pair of gas inlets and outlets in the adsorption tower; a second flow path switching unit that selectively connects one of the other of the gas introduction pipe and the gas discharge pipe and the second heat exchanger to the other of the pair of gas inlet / outlets; a control unit that controls operations of the refrigeration cycle, the first blower, the first flow path switching unit, and the second flow path switching unit, The control unit is When starting the adsorption capacity regeneration process, the first flow path switching unit is controlled to connect the first heat exchanger to one of the pair of gas inlets and outlets, the second flow path switching unit is controlled to connect the second heat exchanger to the other of the pair of gas inlets and outlets, and the first blower is controlled to blow the gas at a predetermined first blowing capacity, and the refrigeration cycle is controlled to heat the gas in the first heat exchanger and cool the gas in the second heat exchanger, An adsorbent regeneration device that, when a predetermined first condition is satisfied during execution of the adsorption capacity regeneration process, controls the first blower to blow the gas at a predetermined second blowing capacity lower than the first blowing capacity.

2. a bypass pipe for allowing the gas that has been passed through the separation device to flow into the adsorption tower without passing through the first heat exchanger; a flow rate adjusting unit that adjusts a first flow rate of the gas passing from the separation device through the first heat exchanger and flowing into the adsorption tower, and a second flow rate of the gas passing from the separation device through the bypass piping and flowing into the adsorption tower, 2. The adsorbent regeneration device according to claim 1, wherein the control unit, during the adsorption capacity regeneration process, causes the flow rate adjustment unit to adjust the flow rate of the gas so that the first flow rate is greater than the second flow rate until a predetermined second condition for terminating the adsorption capacity regeneration process is satisfied, and, when the second condition is satisfied, causes the flow rate adjustment unit to adjust the flow rate of the gas so that the second flow rate is greater than the first flow rate.

3. The refrigeration cycle includes a condenser that condenses the refrigerant, and a second blower that blows air to the condenser, The adsorbent regenerating device according to claim 2 , wherein the control unit controls the second blower to increase the amount of the atmospheric air blown when the second condition is satisfied.

4. 2. The adsorbent regeneration device according to claim 1, which is configured to be capable of regenerating the adsorption capacity of the adsorbent in the removal system configured to be capable of removing the moisture as the removal target from the hydrogen gas as the gas.

5. 5. A removal system comprising the adsorbent regenerator according to claim 1 and the adsorption tower, and configured to be able to remove the target to be removed from the gas.

6. The adsorption system is configured to include a plurality of adsorption towers and to be capable of executing the adsorption removal process for a portion of each of the adsorption towers and the adsorption capacity regeneration process for another portion of each of the adsorption towers, 6. The removal system of claim 5, wherein, when the adsorption removal process for a portion of each of the adsorption towers and the adsorption capacity regeneration process for the other portion of each of the adsorption towers are performed in parallel, the control unit controls the first flow path switching unit to connect one of the pair of gas inlet / outlets in the portion of each of the adsorption towers to one of the gas introduction piping and the gas discharge piping, and to connect the first heat exchanger to one of the pair of gas inlet / outlets in the other portion of each of the adsorption towers, and controls the second flow path switching unit to connect the other of the pair of gas inlet / outlets in the portion of each of the adsorption towers to the other of the gas introduction piping and the gas discharge piping, and to connect the second heat exchanger to the other of the pair of gas inlet / outlets in the other portion of each of the adsorption towers.

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