Carbon Dioxide Capture Equipment

Abstract

To make it possible to improve carbon dioxide utilization efficiency in a carbon dioxide recovery device configured to recover carbon dioxide contained in exhaust gas.SOLUTION: A carbon dioxide capture device includes an absorption section, a storage section, a first control section, and a second control section. The absorption section has an absorber configured to absorb carbon dioxide. The storage section is configured to store carbon dioxide desorbed from the absorption section. The first control section is configured to send carbon dioxide that contains exhaust gas to the absorption section. The second control section is configured to push out the exhaust gas remaining in the absorption section using the carbon dioxide stored in the storage section, to provides the purge gas discharged from the absorption section to a utilization unit for using it in applications where the concentration of carbon dioxide is lower than that stored in the storage section.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a carbon dioxide capture device configured to capture carbon dioxide contained in exhaust gas. [Background technology]

[0002] The following Patent Document 1 discloses a configuration of a carbon dioxide capture device in which purge gas generated in a purge step is discharged to the atmosphere, etc. Here, the carbon dioxide capture device adsorbs carbon dioxide contained in the exhaust gas from the combustion device to an adsorbent in an adsorption section, and then desorbs the carbon dioxide from the adsorbent and moves it to a storage tank.

[0003] The purging step is a step of discharging the exhaust gas remaining in the adsorption section using the carbon dioxide stored in the storage tank before the carbon dioxide is desorbed from the adsorbent. The purge gas is a gas containing the exhaust gas and carbon dioxide. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-069417 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the technology of Patent Document 1 above has a problem in that the purge gas is released into the atmosphere and a portion of the carbon dioxide stored in the storage tank is discarded without being utilized, thereby reducing the utilization efficiency of carbon dioxide.

[0006] One aspect of the present disclosure is to make it possible to improve the efficiency of carbon dioxide utilization in a carbon dioxide capture device configured to capture carbon dioxide contained in exhaust gas. [Means for solving the problem]

[0007] One aspect of the present disclosure is a carbon dioxide capture device configured to capture carbon dioxide contained in exhaust gas. The carbon dioxide capture device includes an absorption unit, a storage unit, a first control unit, and a second control unit.

[0008] The absorption section includes an absorbent configured to absorb carbon dioxide. The storage section is configured to store the carbon dioxide desorbed from the absorption section. The first control unit is configured to send the carbon dioxide containing the exhaust gas to the absorption unit. The second control unit is configured to use the carbon dioxide stored in the storage unit to push out the exhaust gas remaining in the absorption unit, thereby providing the purge gas discharged from the absorption unit to a utilization unit that utilizes the purge gas for an application in which the concentration of the carbon dioxide is lower than that of the carbon dioxide stored in the storage unit.

[0009] According to such a configuration, since the purge gas can be supplied to the utilization section, the utilization rate of carbon dioxide can be improved compared to a conventional configuration in which the purge gas is not utilized.

[0010] In one embodiment of the present disclosure, the storage unit is the first storage unit. The carbon dioxide capture device may further include a second storage unit as the utilization unit. The second control unit may store the purge gas in the second storage unit.

[0011] According to such a configuration, since the purge gas is stored in the second storage section, even if the purge gas is not used immediately, the purge gas can be effectively used without being discharged into the atmosphere, etc. Furthermore, since the purge gas is stored in the second storage section different from the first storage section, the purge gas can be used in a different location for a purpose other than the carbon dioxide in the first storage section.

[0012] In one aspect of the present disclosure, the second control unit may provide the purge gas to a carbon dioxide utilization facility serving as the utilization unit. According to such a configuration, the purge gas can be effectively utilized in a carbon dioxide utilization facility where the carbon dioxide is used for a purpose with a lower concentration than that of the carbon dioxide stored in the storage section.

[0013] In one aspect of the present disclosure, the second control unit may provide the purge gas to an agricultural greenhouse as the utilization unit. With this configuration, the purge gas can be effectively utilized in the agricultural greenhouse.

[0014] According to an embodiment of the present disclosure, the device may further include at least one carbon dioxide concentration sensor and at least one valve. The carbon dioxide concentration sensor may be disposed between the absorbent material and the utilization portion. The valve may be configured to open and close a flow path connecting the absorption unit and the utilization unit. The second control unit may be configured to close the valve when the concentration detected by the carbon dioxide concentration sensor reaches a preset concentration.

[0015] According to this configuration, the concentration of carbon dioxide is monitored, so that it is possible to detect a decrease in the exhaust gas in the absorption section. Then, since the valve can be closed when the exhaust gas decreases, it is possible to prevent the carbon dioxide in the storage section from being used excessively to push out the exhaust gas. In addition, it is possible to prevent the concentration of carbon dioxide used in the utilization section from becoming excessively high, and to adjust the concentration to a suitable concentration for utilization. [Brief description of the drawings]

[0016] [Figure 1] 1 is a schematic diagram showing a schematic configuration of a carbon dioxide capture device according to an embodiment. [Diagram 2] FIG. 2 is a block diagram showing the configuration of a carbon dioxide capture device. [Diagram 3] 13 is a flowchart of a carbon dioxide storage process. [Figure 4] FIG. 2 is a schematic diagram showing a gas flow in an absorption process. [Diagram 5] FIG. 4 is a schematic diagram showing a gas flow in a purging process. [Figure 6] FIG. 4 is a schematic diagram showing a gas flow in a desorption process. [Figure 7] FIG. 4 is a schematic diagram showing a gas flow in a cooling process. [Figure 8]FIG. 2 is a schematic diagram showing a schematic configuration of a carbon dioxide capture device according to a first modified example. [Figure 9] FIG. 11 is a schematic diagram showing a schematic configuration of a carbon dioxide capture device according to a second modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. [1. Embodiment] [1-1. Correspondence between the configuration of the embodiment and the configuration of the present disclosure] The absorption process among the processes performed by the control unit 50 in the embodiment corresponds to the function of the first control unit in the present disclosure, and the purging process corresponds to the function of the second control unit in the present disclosure. Moreover, among the multiple valves 121-126, 221-226 in the embodiment, the valves 122, 222 correspond to the valves in the present disclosure. Moreover, among the multiple carbon dioxide concentration sensors 131-133, 231-233 in the embodiment, the carbon dioxide concentration sensors 132, 232 correspond to the carbon dioxide concentration sensors in the present disclosure.

[0018] [1-2. Configuration] The carbon dioxide capture apparatus 1 of this embodiment is an apparatus configured to extract and store carbon dioxide contained in exhaust gas from a combustion apparatus 5 configured as, for example, an engine, a boiler, or the like. As shown in Fig. 1 and Fig. 2, the carbon dioxide capture apparatus 1 includes a plurality of absorption units 10, 20, a first storage unit 41, and a control unit 50. The carbon dioxide capture apparatus 1 may also include a plurality of pumps 31, 32, and a plurality of valves 121-126, 221-226.

[0019] The absorbing unit 10 is, for example, a metal tank having an absorbent 11 therein. The absorbent 11 is made of a solid material capable of absorbing carbon dioxide. For example, a solid absorbent having an absorbent such as an amine supported on the surface of a porous material can be used as the absorbent 11.

[0020] In this disclosure, "absorption" includes "adsorption." Known adsorbents such as zeolite and activated carbon can be used as the adsorbent. In other words, the absorbent 11 may be configured to absorb or adsorb carbon dioxide as long as it is configured to be able to detach carbon dioxide.

[0021] The absorbing section 20, like the absorbing section 10, is, for example, a metal tank having an absorbing material 21 therein. Six flow paths 91-93, 96-98 (hereinafter referred to as 91-98) are connected to the absorbing units 10, 20, respectively. These flow paths 91-98 are configured, for example, as metal pipes. Three of the six flow paths 91-98, that is, the flow paths 91-93, are used to introduce a predetermined gas to the absorbing units 10, 20. The three flow paths 91-93 for introducing the gas are arranged side by side on one side of the absorbent 11 (for example, below the absorbing units 10, 20 in FIG. 1).

[0022] In particular, the flow path 91 communicates between the absorption units 10, 20 and the combustion device 5, and is used to introduce exhaust gas from the combustion device 5 to the absorption units 10, 20. The flow path 92 communicates between the absorption units 10, 20 and outside air, and is used to introduce outside air to the absorption units 10, 20. The flow path 93 communicates between the absorption units 10, 20 and the first storage unit 41, and is used to introduce carbon dioxide from the first storage unit 41 to the absorption units 10, 20.

[0023] The other three flow paths 96-98 of the six flow paths 91-98 are used to discharge the gas in the absorbing sections 10 and 20 to the outside. The three flow paths 96-98 for discharging the gas are arranged side by side on the opposite side of the absorbent 11 as viewed from the three flow paths 91-93 for introducing the gas (for example, above the absorbing sections 10 and 20 in FIG. 1).

[0024] In particular, the flow path 96 communicates the absorption units 10, 20 with the outside air and is used for discharging exhaust gas passing through the absorption units 10, 20 to the outside air. The flow path 97 communicates the absorption units 10, 20 with the first storage unit 41 and is used for moving carbon dioxide absorbed in the absorption units 10, 20 to the first storage unit 41. The flow path 98 communicates the absorption units 10, 20 with the utilization unit 43 and is used for supplying purge gas discharged from the absorption units 10, 20 to the utilization unit 43.

[0025] In the six flow paths 91-98, valves 121-126 and 221-226 are disposed at the inlets and outlets of the absorbing sections 10 and 20, respectively. The valves 121-126 at the inlets and outlets of the absorbing section 10 correspond in order to the valves 221-226 at the inlets and outlets of the absorbing section 20, and are disposed in the same flow paths 91-98.

[0026] The inlet of the absorbing section 10, 20 refers to a portion around the absorbing section 10, 20 that is upstream of the absorbent 11, 21 in the gas flow, and the outlet of the absorbing section 10, 20 refers to a portion around the absorbing section 10, 20 that is downstream of the absorbent 11, 21 in the gas flow. When the valves 121-126, 221-226 are opened, the absorbing section 10, 20 is in communication with the external configuration, and when the valves 121-126, 221-226 are closed, the absorbing section 10, 20 is in communication with the external configuration.

[0027] Pumps 31, 32 are disposed in a flow path 97 communicating between the absorption units 10, 20 and the first storage unit 41, and in a flow path 98 communicating between the absorption units 10, 20 and the utilization unit 43. The pumps 31, 32 suck out gas such as carbon dioxide in the absorption units 10, 20, pressurize the gas, and send it to the first storage unit 41 or the utilization unit 43.

[0028] The first storage section 41 is a tank configured to store the carbon dioxide desorbed from the absorption sections 10, 20. The first storage section 41 can store the carbon dioxide in a state pressurized by the pump 31. The stored carbon dioxide can be used in another utilization section 42 different from the utilization section 43. However, the utilization sections 42, 43 may be the same object. For example, the utilization sections 42, 43 may each be a carbon dioxide utilization facility, in particular, an agricultural greenhouse.

[0029] 2, the control unit 50 includes a microcomputer having a CPU 51 and a semiconductor memory such as a RAM or a ROM (hereinafter, referred to as a memory 52). Each function of the control unit 50 is realized by the CPU 51 executing a program stored in a non-transient substantial recording medium. In this example, the memory 52 corresponds to the non-transient substantial recording medium storing the program. Furthermore, the program is executed to execute a method corresponding to the program. The control unit 50 may include one microcomputer or multiple microcomputers.

[0030] The control unit 50 executes a carbon dioxide retention process, which will be described later, according to the program. In the carbon dioxide retention process, the control unit 50 controls the operation of the pumps 31, 32 and the valves 121-126, 221-226 to retain or provide carbon dioxide to a predetermined target.

[0031] [1-3. Processing] Next, the carbon dioxide storage process executed by the control unit 50 will be described with reference to the flowchart of Fig. 3. In the carbon dioxide storage process, exhaust gas is alternately introduced from the combustion device 5 to the multiple absorption units 10, 20, so that the exhaust gas passes through one of the absorption units 10, 20. Therefore, the carbon dioxide contained in the exhaust gas from the combustion device 5 is not wasted, and the combustion device 5 is efficiently operated continuously.

[0032] 3, in the carbon dioxide storage process, the control unit 50 performs an absorption step of S110, a purging step of S120, a desorption step of S130, and a cooling step of S140 using the absorption unit 10. In parallel with the processes of S110 to S140, the control unit 50 performs a purging step of S210, a desorption step of S220, a cooling step of S230, and an absorption step of S240 using the absorption unit 20.

[0033] The process time required for the absorption step S110 using the absorption section 10 is set so as to roughly match the total time of the purging step S210, the desorption step S220, and the cooling step S230, all of which are used in the absorption section 20. Similarly, the process time required for the absorption step S240 using the absorption section 20 is set so as to roughly match the total time of the purging step S120, the desorption step S130, and the cooling step S140, all of which are used in the absorption section 10.

[0034] The absorption step, purging step, desorption step, and cooling step using the absorption section 20 are similar to the absorption step, purging step, desorption step, and cooling step using the absorption section 10, and therefore only the steps using the absorption section 10 will be described below. Similarly, with regard to the determination steps in S150 and S250, only S150 will be described.

[0035] In the absorption step of S110, the control unit 50 sends the carbon dioxide containing exhaust to the absorption unit 10. At this time, as shown in FIG. 4, the control unit 50 opens valves 121 and 124 and closes the other valves 122-123, 125-126. Then, the exhaust from the combustion device 5 flows along the route R1 shown in FIG. 4. That is, the exhaust passes through the flow path 91 and the valve 124 and is introduced into the absorption unit 10, and most of the carbon dioxide in the exhaust is absorbed by the absorbent 11. Then, the exhaust with reduced carbon dioxide is released into the atmosphere through the valve 121 and the flow path 96.

[0036] In the carbon dioxide recovery device 1, the exhaust gas provided to the absorption section 10 may be subjected to pretreatment between the combustion device 5 and the absorption section 10, including at least one of purification such as desulfurization, denitrification, and dehydration, and adaptation to a temperature suitable for absorption by the absorbent 11.

[0037] The control unit 50 monitors, for example, the duration of the absorption step, that is, the time from when the valves 121 and 124 are opened and the other valves 122 to 123, 125 to 126 are closed, using a timer (not shown). When the duration of the absorption step reaches or exceeds a preset absorption step duration, the control unit 50 ends the process of S110 and performs the process of S120.

[0038] In the purge step of S120, the control unit 50 uses the carbon dioxide stored in the first storage unit 41 to push out the exhaust gas remaining in the absorption unit 10. Then, the control unit 50 provides the purge gas discharged from the absorption unit 10 to the utilization unit 43 that utilizes the carbon dioxide at a lower concentration than the concentration of the carbon dioxide stored in the first storage unit 41.

[0039] 5, the control unit 50 opens the valves 122 and 126 and closes the other valves 121, 123 to 125. Furthermore, the control unit 50 drives the pump 32. Then, the carbon dioxide stored in the first storage unit 41 flows along the route R2 shown in FIG.

[0040] That is, carbon dioxide is introduced into the absorption section 10 from the first storage section 41 through the flow path 93 and the valve 126. The carbon dioxide mixes with the exhaust gas remaining in the absorption section 10 and pushes the exhaust gas into the flow path 98. The pushed-out exhaust gas and carbon dioxide constitute a purge gas, which is the gas remaining after the absorption section 10 has been purged.

[0041] The purge gas is supplied to the utilization unit 43 via the valve 122, the flow path 98, and the pump 32. Then, when the duration of the purge process becomes equal to or longer than a preset purge process duration, the control unit 50 ends the process of S120 and performs the process of S130.

[0042] In the desorption step of S130, the control unit 50 desorbs the carbon dioxide absorbed in the absorption unit 10 and stores the desorbed carbon dioxide in the first storage unit 41. At this time, as shown in FIG. 6, the control unit 50 opens only the valve 123 and closes the other valves 121-122, 124-126. Furthermore, the control unit 50 heats the absorbent 11 until the absorbent 11 reaches a temperature at which the absorbent 11 can desorb carbon dioxide, and drives the pump 31. Any method can be used to heat the absorbent 11. For example, a heat exchanger, a heater, or the like provided in the combustion device 5 can be used as the heating method. When the carbon dioxide capture device 1 operates in this manner, the carbon dioxide absorbed in the absorption unit 10 flows along the route R3 shown in FIG. 6.

[0043] That is, carbon dioxide is introduced from the absorbing unit 10 through the valve 123, the flow path 97, and the pump 31 into the first storage unit 41. The pump 31 functions to suck the carbon dioxide out of the absorbing unit 10 and to pressurize it toward the first storage unit 41 so that the carbon dioxide is stored in the first storage unit 41. At this time, the inside of the absorbing unit 10 is reduced in pressure relative to atmospheric pressure. When the duration of the desorption step becomes equal to or longer than a preset desorption step duration time, the control unit 50 ends the process of S130 and carries out the process of S140.

[0044] The control unit 50 cools the absorbing unit 10 in the cooling step of S140. At this time, as shown in Fig. 7, the control unit 50 opens only the valve 125 and closes the other valves 121-124 and 126. Then, since the pressure in the absorbing unit 10 is reduced, outside air is naturally introduced into the absorbing unit 10, and the absorbing unit 10 is cooled by the outside air. The outside air flows along a route R4 shown in Fig. 7.

[0045] That is, the outside air is introduced into the absorbing section 10 through the flow path 92 and the valve 125. When the duration of the cooling step becomes equal to or longer than a preset cooling step duration, the control section 50 ends the process of S140 and carries out the process of S150.

[0046] In the cooling step, not only the valve 125 but also the valve 121 for communicating with the outside air at the outlet side of the absorption section 10 may be opened. In this case, the breathability within the absorption section 10 can be improved, and the cooling of the absorbent material 11 can be promoted.

[0047] The control unit 50 determines whether or not to end the carbon dioxide storage process in S150. The control unit 50 determines to end the carbon dioxide storage process, for example, when the first storage unit 41 reaches a predetermined pressure, when the processes of S110 to S140 have been repeated a preset number of times, etc.

[0048] When the control unit 50 determines not to end the carbon dioxide storage process, it repeats the processes from S110 onward. When the control unit 50 determines to end the carbon dioxide storage process, it ends the carbon dioxide storage process.

[0049] [1-4. Effects] According to the embodiment described above in detail, the following effects are achieved. (1a) One aspect of the present disclosure is a carbon dioxide capture device 1 configured to capture carbon dioxide contained in exhaust gas from a combustion device 5. The carbon dioxide capture device 1 includes an absorption unit 10, a first storage unit 41, and a control unit 50.

[0050] The absorption section 10 has an absorbent 11 configured to absorb carbon dioxide. The first storage section 41 is configured to store the carbon dioxide desorbed from the absorption section 10. The control unit 50 is configured to send the carbon dioxide containing exhaust gas to the absorption unit 10 in the absorption steps S110 and S240. The control unit 50 is configured to push out the exhaust gas remaining in the absorption unit 10 by using the carbon dioxide stored in the first storage unit 41 in the purging steps S120 and S210. The control unit 50 is configured to provide the purge gas discharged from the absorption unit 10 to a utilization unit 43 that utilizes the carbon dioxide at a lower concentration than the concentration of the carbon dioxide stored in the first storage unit 41.

[0051] According to such a configuration, the purge gas can be provided to the utilization section 43 for low-concentration applications, so that the utilization rate of carbon dioxide can be improved compared to a conventional configuration in which the purge gas is not used.

[0052] (1b) The carbon dioxide capture device 1 may recycle the purge gas to the absorption section 10 to reuse the carbon dioxide contained in the purge gas, in which case the utilization rate of carbon dioxide can be improved. However, if the processing amount of the purge gas increases, the amount of exhaust gas that can be newly processed decreases, and there is a problem that extra energy is required to extract carbon dioxide from the exhaust gas. This is because in order for the absorption section 10 to absorb and desorb carbon dioxide, it is necessary to heat and cool the absorption section 10, which requires energy.

[0053] For this reason, in the configuration of the present disclosure, the purge gas is not recirculated to the absorption section 10, but is instead supplied to the utilization section 43 so as not to consume excess energy.

[0054] (1c) In one embodiment of the present disclosure, the control unit 50 is configured to provide a purge gas to the carbon dioxide utilization facility serving as the utilization unit 43 in the purging steps S120 and S210. According to such a configuration, the purge gas can be effectively utilized in a carbon dioxide utilization facility where the carbon dioxide stored in the first storage section 41 is used for a purpose with a lower concentration.

[0055] (1d) In one embodiment of the present disclosure, the control unit 50 is configured to provide purge gas to the agricultural greenhouse serving as the utilization unit 43 in the purge steps S120 and S210. With this configuration, the purge gas can be effectively utilized in the agricultural greenhouse.

[0056] 2. Other embodiments Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and can be implemented in various modified forms.

[0057] (2a) In the above embodiment, the pumps 31, 32 and the valves 121-126, 221-226 are configured to be operated in accordance with the operation duration of each process, but this is not limited to the above. For example, as in the carbon dioxide capture device 2 of the first modified example shown in Fig. 8, carbon dioxide concentration sensors 131-133, 231-233 may be further provided, and the pumps 31, 32 and the valves 121-126, 221-226 may be operated in accordance with the concentration of carbon dioxide.

[0058] Here, the carbon dioxide concentration sensors 131-133, 231-233 may be disposed near the outlet of the absorbing section 10, upstream of the gas flow of the valves 121-123, 221-223. In other words, the carbon dioxide concentration sensors 131-133, 231-233 may be disposed between the absorbents 11, 21 and the valves 121-123, 221-223. The control section 50 is configured to close the valves 122, 222 when the concentrations detected by the carbon dioxide concentration sensors 131-133, 231-233 in the purging steps S120, S210 become equal to or higher than a preset concentration.

[0059] In this embodiment, the valves 122 and 222 can be configured to be closed based on the concentration detected by the carbon dioxide concentration sensors 132 and 232 arranged in the flow path 98 connected to the utilization section 43.

[0060] The concentration when the valves 122 and 222 are closed may be the concentration when the exhaust gas in the absorption units 10 and 20 is purged, and this concentration may be set experimentally. However, the concentration when the valves 122 and 222 are closed is set to a concentration at least lower than the concentration of carbon dioxide stored in the first storage unit 41.

[0061] According to this configuration, the concentration of carbon dioxide is monitored, so that it is possible to detect a decrease in the exhaust gas in the absorption section 10. Then, when the exhaust gas decreases, the valves 122, 222 can be closed, so that the carbon dioxide gas in the first storage section 41 is not used excessively to push out the exhaust gas. Also, it is possible to prevent the concentration of carbon dioxide used in the utilization section 43 from becoming excessively high, and to adjust the concentration to a suitable concentration for utilization.

[0062] (2b) In the above first modified example, the carbon dioxide concentration sensors 131-133, 231-233 are disposed between the absorbents 11, 21 and the valves 121-123, 221-223, but this is not limiting. The carbon dioxide concentration sensors 131-133, 231-233 may be disposed downstream of the valves 121-123, 221-223. When the carbon dioxide concentration sensors 131-133, 231-233 are disposed downstream of the valves 121-123, 221-223, the carbon dioxide concentration sensors 131-133, 231-233 may be disposed immediately adjacent to the valves 121-123, 221-223.

[0063] In particular, the carbon dioxide concentration sensor 132, 232 used to detect the concentration when the valve 122, 222 is closed at least in the purging step may be disposed between the absorbent 11 and the utilization section 43. The carbon dioxide concentration sensor 132, 232 may be disposed immediately downstream of the valve 122, 222.

[0064] If the carbon dioxide concentration sensor 132, 232 is disposed downstream of the valve 122, 222, it is possible to prevent low-purity gas, including exhaust, from remaining between the absorbent 11 and the valve 122, 222. However, in order to prevent a large amount of high-concentration carbon dioxide from being consumed in the purging process, it is preferable that the carbon dioxide concentration sensor 132, 232 is disposed as close to the valve 122, 222 as possible.

[0065] As in the first modified example, the carbon dioxide concentration sensors 131-133, 231-233 may be arranged between the absorbents 11, 21 and the valves 121-123, 221-223. With this configuration, the internal concentration of carbon dioxide in the absorbing section 10 can be measured using the carbon dioxide concentration sensors 131-133, 231-233.

[0066] (2c) In the above embodiment, the purge gas is configured to be directly applied to the utilization section 43, but the present invention is not limited to this. For example, as in a second modified carbon dioxide capture device 3 shown in Fig. 9, a second storage section 46 may be further provided, and the control section 50 may be configured to store the purge gas in the second storage section 46 in the purging steps S120 and S210.

[0067] According to such a configuration, the purge gas is stored in the second storage portion 46, so that even if the purge gas is not used immediately, the purge gas can be effectively used without being discharged into the atmosphere or the like.

[0068] (2d) In the case of the carbon dioxide capture device 3 of the second modified example shown in Fig. 9, the purge gas may be applied to the utilization section 43 without moving the second storage section 46. Also, the second storage section 46 may be moved to a location where another utilization section 47 is present, and then the purge gas may be applied to the utilization section 47.

[0069] (2e) In the above embodiment, the process time required for the absorption step in the first absorption section 10 is set to be approximately equal to the total time of the purging step, desorption step, and cooling step in the second absorption section 20, but this is not limited to the configuration. The process time required for the absorption step in the first absorption section 10 does not have to be equal to the total time of the purging step, desorption step, and cooling step in the other absorption sections 20, etc. For example, three or more absorption sections 10, 20 may be provided, and in this case, in particular, the process time required for the absorption step in the first absorption section 10 does not have to be equal to the total time of the purging step, desorption step, and cooling step in the other absorption sections 20, etc.

[0070] (2f) In the above embodiment, the control unit 50 is configured to end the process of S140 when the duration of the cooling step reaches or exceeds a preset cooling step duration, but is not limited to this configuration. For example, the control unit 50 may end the process of S140 when the pressure in the absorbing units 10, 20 reaches a preset pressure.

[0071] (2g) The control unit 50 and the method executed by the control unit 50 described in the present disclosure may be realized by a dedicated computer provided by configuring a processor and a memory programmed to execute one or more functions embodied in a computer program. Alternatively, the control unit 50 and the method executed by the control unit 50 described in the present disclosure may be realized by a dedicated computer provided by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the control unit 50 and the method described in the present disclosure may be realized by one or more dedicated computers configured by a combination of a processor and a memory programmed to execute one or more functions and a processor configured with one or more hardware logic circuits. In addition, the computer program may be stored in a computer-readable non-transitory tangible recording medium as instructions executed by a computer. The method for realizing the functions of each unit included in the control unit 50 does not necessarily need to include software, and all of the functions may be realized using one or more hardware.

[0072] (2h) Multiple functions possessed by one component in the above embodiments may be realized by multiple components, or one function possessed by one component may be realized by multiple components. Also, multiple functions possessed by multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Also, part of the configuration of the above embodiments may be omitted. Also, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another of the above embodiments.

[0073] (2i) In addition to the carbon dioxide capture apparatus 1 described above, the present disclosure can be realized in various forms, such as a system including the carbon dioxide capture apparatus 1 as a component, a program for causing a computer to function as the carbon dioxide capture apparatus 1, a non-transitory physical recording medium such as a semiconductor memory on which this program is recorded, and a carbon dioxide storage method. [Explanation of symbols]

[0074] 1, 2, 3...carbon dioxide recovery device, 5...combustion device, 10, 20...absorption section, 11, 21...absorbent, 31, 32...pump, 41...first storage section, 42, 43...utilization section, 46...second storage section, 50...control section, 51...CPU, 52...memory, 91-98...flow path, 121-126, 221-226...valves, 131-133, 231-233...carbon dioxide concentration sensor.

Claims

1. 1. A carbon dioxide capture device configured to capture carbon dioxide contained in an exhaust gas, comprising: an absorption section having an absorbent material configured to absorb carbon dioxide; A storage section configured to store the carbon dioxide desorbed from the absorption section; A first control unit configured to send the carbon dioxide containing exhaust gas to the absorption unit and release the exhaust gas having reduced carbon dioxide gas into the atmosphere; a second control unit configured to, in a state in which exhaust gas is not sent to the absorption unit, push out the exhaust gas that has already been sent to the absorption unit and remains in the absorption unit by using the carbon dioxide stored in the storage unit, thereby providing the purge gas discharged from the absorption unit to a utilization unit that stores or utilizes the purge gas at a concentration lower than the concentration of carbon dioxide stored in the storage unit; a third control unit configured to desorb the carbon dioxide absorbed in the absorption unit after the second control unit pushes out the exhaust gas remaining in the absorption unit and store the desorbed carbon dioxide in the storage unit; A carbon dioxide capture device comprising:

2. The carbon dioxide capture device according to claim 1, The storage section is a first storage section, The utilization section further includes a second storage section, The second control unit stores the purge gas in the second storage unit. A carbon dioxide capture device configured as follows.

3. The carbon dioxide capture device according to claim 1 or 2, The second control unit provides the purge gas to a carbon dioxide utilization facility serving as the utilization unit. A carbon dioxide capture device configured as follows.

4. The carbon dioxide capture device according to claim 3, The second control unit provides the purge gas to an agricultural house as the utilization unit. A carbon dioxide capture device configured as follows.

5. The carbon dioxide capture device according to any one of claims 1 to 4, At least one valve that opens and closes a flow path connecting the absorption unit and the utilization unit; At least one carbon dioxide concentration sensor disposed between the absorbent and the utilization portion; Further equipped with The second control unit closes the valve when the concentration detected by the carbon dioxide concentration sensor reaches a preset concentration. A carbon dioxide capture device configured as follows.

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