Heat transfer medium circuit, heat pump, and carbon dioxide recovery device

Abstract

The heat transfer medium circuit is provided with: a plurality of heat exchange units; a compressor that compresses the heat transfer medium flowing through the heat exchange unit; a main path that connects the compressor and the plurality of heat exchange units in series and circulates a heat transfer medium; and a reversing mechanism that switches the heat transfer medium flowing in the first flow direction in the main path to a second flow direction opposite to the first flow direction. Between the two heat exchange parts, at least a part of the heat energy absorbed by the heat transfer medium in one heat exchange part is moved to the other heat exchange part.

Description

Technical Field

[0001] The present invention relates to a heat transfer medium circuit, a heat pump, and a carbon dioxide recovery device. Background Art

[0002] Conventionally, measures aimed at mitigating climate change or reducing its impact have been underway. To achieve this goal, research and development related to reducing carbon dioxide emissions have been carried out. As one of the measures, the following technologies have been proposed: capturing carbon dioxide in the atmosphere and storing the captured carbon dioxide in the ground in the form of gas or liquid, etc.; and converting the captured carbon dioxide into valuable substances such as fuels or chemicals as a carbon source and utilizing them.

[0003] Among them, the use of direct air capture technology (DAC) to capture carbon dioxide has been proposed. For example, Patent Document 1 proposes a method of releasing carbon dioxide by bringing water vapor into contact with an adsorbent when recovering carbon dioxide adsorbed by the adsorbent.

[0004] [Prior Art Documents]

[0005] (Patent Document)

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2017-528318 Summary of the Invention

[0007] [Problems to be Solved by the Invention]

[0008] In such a carbon dioxide recovery device, an adsorption step of adsorbing carbon dioxide onto a solid adsorbent material and a desorption step of desorbing carbon dioxide from the adsorbent material are performed. The adsorption step and the desorption step are alternately repeated. In terms of the characteristics of the absorbent material, the adsorption step is performed at room temperature (25°C) for the adsorbent material, while the desorption step is performed at a high temperature (e.g., 90°C) for the adsorbent material.

[0009] In the case of using a carbon dioxide recovery device having a plurality of modules each having an adsorbent material and staggering the phases of the operation cycles of the respective modules, it is necessary to supply heat energy equivalent to the heat capacity of the adsorbent material or the heat of desorption of carbon dioxide, i.e., the heat energy required in the desorption step, using a heat pump or the like in accordance with the operation cycle of each module. However, there is a problem that the supply of this heat energy consumes a large amount of electricity.

[0010] The problem to be solved by the present invention is to solve the above problems and provide a heat transfer medium circuit, a heat pump, and a carbon dioxide recovery device that can operate a heat pump with a higher coefficient of performance (COP) and reduce the power consumed in the supply of thermal energy. Furthermore, it contributes to the mitigation or reduction of the impact of climate change.

[0011] [Technical means for solving the problem]

[0012] (1) A heat transfer medium circuit, preferably comprising: a plurality of heat exchange parts; a compressor that compresses the heat transfer medium flowing in the heat exchange parts; a main path that serially connects the compressor and the plurality of heat exchange parts to circulate the heat transfer medium; and a reversing mechanism that switches the heat transfer medium flowing in the first flow direction in the main path to a second flow direction opposite to the first flow direction; and between the two heat exchange parts, at least a part of the thermal energy absorbed by the heat transfer medium in one of the heat exchange parts is transferred to the other heat exchange part.

[0013] (2) Additionally, preferably, the heat transfer medium circuit has three or more of the above-mentioned heat exchange parts, and for each heat exchange part, there is a bypass part that selectively bypasses the inflow of the heat transfer medium to the heat exchange part where no thermal energy transfer occurs.

[0014] (3) Additionally, preferably, the reversing mechanism is a reversing path having a plurality of pipes, and the plurality of pipes connect the upstream side and the downstream side via a switching valve across the compressor in the main path.

[0015] (4) Additionally, preferably, the heat transfer medium circuit has an expansion valve that expands the heat transfer medium flowing into each heat exchange part, and when the heat transfer medium flows into the heat exchange part as the heat absorption object, the heat transfer medium is expanded to lower the temperature.

[0016] (5) The heat pump preferably has the heat transfer medium circuit according to any one of (1) to (4) above.

[0017] (6) Additionally, the carbon dioxide recovery device preferably comprises: the heat pump according to (5) above; and a plurality of carbon dioxide recovery modules having an adsorbent for adsorbing and desorbing carbon dioxide, performing an adsorption process and a desorption process, the adsorption process being to adsorb carbon dioxide to the adsorbent, and the desorption process being to desorb the carbon dioxide adsorbed to the adsorbent; and the heat exchange parts are respectively arranged in the carbon dioxide recovery modules, and the heat pump moves thermal energy between the plurality of carbon dioxide recovery modules.

[0018] (Effects of the invention)

[0019] (1) According to the present invention, it is possible to provide a heat transfer medium circuit that can operate a heat pump with a higher COP and reduce the power consumption in the supply of thermal energy.

[0020] (2) Further, since the heat transfer medium circuit includes three or more of the aforementioned heat exchange units, and a bypass unit is provided for each of the aforementioned heat exchange units, the bypass unit selectively bypasses the inflow of the aforementioned heat transfer medium to the heat exchange unit where no thermal energy transfer occurs. Therefore, thermal energy does not move to the heat exchange unit where no thermal energy transfer occurs and can be transferred efficiently.

[0021] (3) In addition, since the aforementioned reversing mechanism is a reversing path including a plurality of pipes, and the plurality of pipes connect the upstream side and the downstream side via a switching valve across the compressor in the aforementioned main path, a reversing mechanism can be implemented at low cost without using a complex device or the like.

[0022] (5) Since the heat pump includes the heat transfer medium circuit described in (1) to (4), the heat pump can operate with a higher COP and reduce the power consumption in the supply of thermal energy.

[0023] (6) Since the carbon dioxide recovery device includes the heat pump described in (5), it is possible to provide a heat transfer medium circuit that can reduce the power consumption for supplying thermal energy to the carbon dioxide recovery module. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a diagram showing a schematic configuration of the carbon dioxide recovery device 1 according to the embodiment.

[0025] Figure 2 is a perspective view of the module unit 10 according to the embodiment.

[0026] Figure 3 is a perspective view of the module 11 according to the embodiment.

[0027] Figure 4 is a diagram for explaining the operation states and output ratios of the adsorption device and the desorption device when there is one module 11 in the module unit 10.

[0028] Figure 5 is a diagram for explaining the operation states and output ratios of the adsorption device and the desorption device when there are two modules 11 in the module unit 10.

[0029] Figure 6 is a diagram for explaining the operation states and output ratios of the adsorption device and the desorption device when there are sixteen modules 11 in the module unit 10.

[0030] Figure 7 It is a graph showing Figures 4 to 6 in an example of the operation cycle shown in, the output ratio of the adsorption device and the desorption device, the difference between the upper and lower limits of the output of each device, that is, the variation range, and the relationship with the number of modules.

[0031] Figure 8 It is a diagram for explaining the recovery and supply of heat energy between two modules 11.

[0032] Figure 9 It is a graph showing the relationship between the time error Z0 and the number of modules.

[0033] Figure 10 It is a graph showing the number of modules and the operation of each module.

[0034] Figure 11 It is a diagram showing the heat transfer medium circuit of the heat pump 80 in the embodiment.

[0035] Figure 12 It is a diagram showing an example of the flow of the heat transfer medium in the heat transfer medium circuit of the heat pump 80.

[0036] Figure 13 It is a diagram showing an example of the flow of the heat transfer medium in the heat transfer medium circuit of the heat pump 80.

[0037] Figure 14 It is a diagram showing an example of the heat transfer medium circuit of the heat pump 80 when the number of modules is set to N×2.

[0038] Figure 15 It is a diagram showing an example of the flow of the heat transfer medium in the heat exchange section 16. Detailed Embodiment

[0039] Hereinafter, embodiments of the present invention will be described with reference to the drawings and the like. In addition, including Figure 1 the following figures are schematically drawn figures, and for easy understanding, the sizes and shapes of each part are appropriately exaggerated.

[0040] (Embodiment)

[0041] Figure 1 It is a diagram showing the schematic structure of the carbon dioxide recovery device 1 of this embodiment.

[0042] The carbon dioxide recovery device 1 is applied, for example, in the direct air capture technology (Direct Air Capture, DAC) for recovering carbon dioxide in the atmosphere in order to reduce the carbon dioxide concentration in the atmosphere. The carbon dioxide recovered by the carbon dioxide recovery device 1 is stored underground or reused as fuel or materials.

[0043] The carbon dioxide recovery device 1 includes a module unit 10, a fan 61, a vacuum pump 62, a compressor 63, a tank 64, a heat pump 80, a control unit 50, an exhaust gas pipeline 71, a carbon dioxide recovery pipeline 72, etc. The carbon dioxide recovery device 1 adsorbs carbon dioxide in the inhaled gas such as the atmosphere to recover it. And, the carbon dioxide recovery device 1 desorbs the recovered carbon dioxide and stores it in the tank 64, and discharges the gas other than carbon dioxide to the outside of the carbon dioxide recovery device 1.

[0044] In the following description, Figure 1 the flow of the gas from "suction" to "exhaust" shown (i.e., Figure 1 the flow of the gas from left to right in the plane of the paper) is defined as the flow from upstream to downstream.

[0045] The control unit 50 controls the operations of each part of the carbon dioxide recovery device 1. The control unit 50 controls, for example, the opening and closing operations of the valves 12, 13, 14 provided in each module 11, and the driving and stopping of devices such as the fan 61, the vacuum pump 62, and the heat pump 80 used in the adsorption or desorption of carbon dioxide. The control unit 50 includes, for example, a Central Processing Unit (CPU), a Read Only Memory (ROM), a Random Access Memory (RAM), etc.

[0046] The module unit 10 is formed by arranging a plurality of modules 11 in parallel. In the present embodiment, as an example, an example in which the module unit 10 includes 16 modules 11 will be described. In Figure 1 the modules 11 in the module unit 10 are sequentially numbered in the order of "(#1)", "(#2)" after the symbols from the upper side in the plane of the paper.

[0047] The module 11 is a carbon dioxide recovery module having an adsorbent 20 for adsorbing carbon dioxide inside. The module 11 has a valve 12 on the upstream side of the adsorbent 20, and valves 13 and 14 provided on the downstream side of the adsorbent 20.

[0048] The valve 12 is an inlet for sucking the atmosphere or the like into the inside of the module 11, and the valve 13 is an outlet for discharging the gas to the outside of the module 11. The valve 13 is connected to the exhaust gas pipeline 71 for discharging the gas passing through the module 11 to the outside of the carbon dioxide recovery device 1.

[0049] The valve 14 is an outlet for discharging the gas to the outside of the module 11, and is connected to the carbon dioxide recovery pipeline 72 provided with a tank 64 or the like for storing the recovered carbon dioxide.

[0050] A plurality of modules 11 of the module unit 10 are connected in parallel to the exhaust pipeline 71 via a valve 13, and are also connected in parallel to the carbon dioxide recovery pipeline 72 via a valve 14.

[0051] In addition, regarding the valve 12 and the valve 13, in Figure 1 for the sake of easy understanding, an example is shown in which one is provided in each module 11. However, in the carbon dioxide recovery device 1 of the present embodiment, actually, as will be described later in Figure 2 and the like, two are respectively provided in each module 11.

[0052] Details regarding the shape and the like of the module 11 will be described below.

[0053] By being driven, the fan 61 generates a flow of gas from "suction" to "exhaust" in the module unit 10. Thereby, the atmosphere is supplied into the module 11.

[0054] The fan 61 of the present embodiment is as Figure 1 shown, and one is provided on the exhaust pipeline 71 on the downstream side of the module unit 10. In addition, without being limited thereto, regarding the fan 61, an intake pipeline (not shown) that is connected to the valve 12 of each module 11 and supplies gas to the module 11 may be provided on the upstream side of the module unit 10, and one fan 61 may be provided on the intake pipeline, or a configuration in which one fan 61 is provided on each of the intake pipeline on the upstream side and the exhaust pipeline 71 on the downstream side of the module unit 10 may be adopted.

[0055] The vacuum pump 62 is located on the downstream side of the module unit 10 and is provided in the carbon dioxide recovery pipeline 72. The vacuum pump 62 sucks the gas inside the module 11 to make the surroundings of the adsorption material 20 into a vacuum. In addition, the vacuum pump 62 sucks the carbon dioxide desorbed from the adsorption material 20 and guides it to a compressor 63 located on the more downstream side of the carbon dioxide recovery pipeline 72.

[0056] The compressor 63 is located on the downstream side of the vacuum pump 62 and is provided in the carbon dioxide recovery pipeline 72. The compressor 63 is a compressor that compresses the carbon dioxide desorbed from the adsorption material 20 at a prescribed pressure.

[0057] The tank 64 is located on the downstream side of the compressor 63 and is connected to the carbon dioxide recovery pipeline 72. The tank 64 stores the carbon dioxide compressed by the compressor 63 in a prescribed state (gas or liquid state).

[0058] When the heat pump 80 performs a desorption process on each module 11 of the module unit 10, it supplies thermal energy for heating the inside of the module 11 to a specified temperature. In addition, the heat pump 80 recovers thermal energy that is not required during the adsorption process in each module 11. This heat pump 80 is a so-called waste heat recovery type heat pump.

[0059] The heat pump 80 includes a pipe 82 (refer to the following Figure 11 ) that encloses a heat transfer medium not shown. The pipe 82 is a flow path through which the heat transfer medium flows. The heat pump 80 supplies thermal energy to each module 11 or recovers unnecessary thermal energy through the heat transfer medium that passes through the pipe 82.

[0060] Details of the heat transfer medium circuit of this heat pump 80 will be described below.

[0061] Figure 2 is a perspective view of the module unit 10 of the present embodiment. In Figure 2 , the module 11, the pipe as the exhaust pipe line 71, and the fan 61 are shown.

[0062] Figure 3 is a perspective view of the module 11 of the present embodiment. In Figure 3 , a part of the inside of the module 11 is also shown.

[0063] Figure 2 The shown module unit 10 has a total of 16 modules 11, 8 on each of two opposite faces in a direction orthogonal to the extending direction (long side direction) of the pipe as the exhaust pipe line 71. Among these modules 11, the valves 13 are connected to the exhaust pipe line 71 and are arranged side by side with respect to the exhaust pipe line 71.

[0064] Figure 2 The arrangement of the shown module 11 with respect to the exhaust pipe line 71 is an example, and other arrangements may also be adopted.

[0065] As Figure 3 shows, the module 11 includes a box-shaped frame 15, a heat exchange part 16 disposed inside the frame 15, and valves 12 and 13 provided on two opposite faces of the frame 15. The module 11 also includes a valve 14 not shown in Figure 3 . This valve 14 is provided, for example, on the inner side of the frame 15 closer to the inside than the butterfly valve of the valve 12 or on the inner side of the frame 15 closer to the inside than the unshown butterfly valve of the valve 13 via a branch and a pipe not shown. The valve 14 and these branches, etc. are omitted from the description in Figure 2 , Figure 3 for the sake of easy understanding.

[0066] The housing 15 is a box-shaped component and has a heat exchange section 16 inside. In the present embodiment, as an example, the case where the housing 15 is in the shape of a rectangular parallelepiped will be described.

[0067] The valves 12, 13, and 14 are valves that control the inflow of gas into the housing 15 of the module 11 and the discharge of gas outside the housing 15. The valve 12 is the inlet of gas into the housing 15, and the valves 13 and 14 are the outlets of gas from the housing 15.

[0068] Regarding the valves 12 and 13, by opening them, a gas containing carbon dioxide (e.g., the atmosphere) is supplied to the adsorbent 20 inside the housing 15 of the module 11, and the gas that has passed through the adsorbent 20 is exhausted to the exhaust pipe line 71.

[0069] The valve 14 (refer to Figure 1 ) is connected to the carbon dioxide recovery pipe line 72. By opening the valve 14, the carbon dioxide released from the adsorbent 20 goes to the downstream side vacuum pump 62 or the like.

[0070] The heat exchange section 16 allows the refrigerant supplied from the heat pump 80 and the heat transfer medium serving as the heat source to flow, and adjusts the surrounding temperature through heat exchange. In the present embodiment, in the heat exchange section 16, a plurality of layers 17 are arranged in a corrugated manner in the height direction of the housing 15 by means of jigs (not shown) or the like.

[0071] The layer 17 includes a plurality of thin plate-shaped fins (not shown) and a hose (pipe) (not shown). Between the fins, particulate adsorbent 20 is filled. The hose is a pipe through which the heat transfer medium for heat exchange flows.

[0072] The layer 17 is arranged as Figure 3 shown, such that the peak portions of the corrugations of the layers 17 stacked in a corrugated manner are located on the valve 12 side and the valve 13 side. By arranging the layer 17 in this way, the contact area with the inhaled gas (atmosphere) can be greatly increased, and the adsorbent can adsorb carbon dioxide with high efficiency.

[0073] The module 11 of the present embodiment has two valves 12 and two valves 13 for one housing 15. In addition, without being limited thereto, a configuration in which three or more valves 12 and valves 13 are provided respectively may also be adopted.

[0074] In addition, the number of valves 14 provided in the module 11 can also be appropriately set according to the installation position in the housing 15 and the like. In the case of the module 11 of the present embodiment, the number of valves 14 provided for one module 11 can also be appropriately set, for example, between 1 and 16.

[0075] By providing a plurality of valves 12 and 13, which serve as inlets (suction ports) and outlets (exhaust ports) for gas, on the housing 15 of a module 11, it is possible to reduce the pressure loss of the gas when it flows into the housing 15 of the module 11 and when it is discharged from the housing 15 to the outside. If only one valve 12 and one valve 13 are provided on the housing 15 respectively, the change in the diameter of the gas flow path becomes large, resulting in a large pressure loss. In contrast, by providing a plurality of inlets and outlets, the change in the diameter of the flow path becomes small, and such pressure loss can be reduced. In addition, from the perspective of arranging a plurality of modules 11 each having a plurality of valves 12 and 13, etc., the housing 15 is preferably in the shape of a rectangular parallelepiped.

[0076] The adsorbent 20 is a particulate component that has the property of adsorbing carbon dioxide at a low temperature (-30°C to 50°C) and desorbing (releasing) carbon dioxide at a high temperature (50°C to 110°C) when the concentration of carbon dioxide in the surrounding environment is low. Examples of such an adsorbent 20 include a carbon dioxide adsorbent formed of solid amine.

[0077] In the present embodiment, as an example, an example will be described in which the temperature at which the adsorbent 20 adsorbs carbon dioxide is set to 25°C, which is normal temperature, and the temperature at which the adsorbent 20 desorbs carbon dioxide is set to 90°C.

[0078] (Regarding carbon dioxide recovery)

[0079] The carbon dioxide recovery device 1 alternately performs an adsorption process in which carbon dioxide in the inhaled gas such as air is adsorbed onto the adsorbent 20 in the module 11 and a desorption process in which the carbon dioxide adsorbed on the adsorbent 20 is desorbed, and compresses and stores the desorbed carbon dioxide in the tank 64, thereby removing and recovering carbon dioxide from the air.

[0080] The adsorption process is a process in which carbon dioxide is adsorbed onto the adsorbent 20 in the module 11. In the adsorption process, the valves 12 and 13 of the module 11 are opened, and the valve 14 is closed. The fan 61 is driven to generate a gas flow from the upstream to the downstream, and a gas containing carbon dioxide (e.g., air) is inhaled through the valve 12.

[0081] The inhaled gas passes through the adsorbent 20 in the module 11. At this time, the temperature inside the module 11 is normal temperature (25°C), and the carbon dioxide in the gas is adsorbed onto the adsorbent 20. Gases other than carbon dioxide, such as nitrogen or oxygen, pass through the valve 13 and the exhaust pipeline 71 and are discharged to the outside of the carbon dioxide recovery device 1.

[0082] The desorption process is a process for desorbing carbon dioxide from the adsorbent 20 in the module 11. In the desorption process, the valves 12 and 13 of the module 11 are closed, and the valve 14 is opened. The vacuum pump 62 operates to suck air inside the housing 15 of the module 11 to reduce the pressure. At the same time, by means of the heat pump 80, the heat transfer medium serving as the heat source flows through the heat exchange section 16 in the module 11 to supply heat energy and heat the heat exchange section 16. Thereby, the adsorbent 20 is also heated to a prescribed temperature (90 °C) sufficient for the desorption process, and the carbon dioxide adsorbed on the adsorbent 20 is desorbed.

[0083] The desorbed carbon dioxide is sucked by the vacuum pump 62, flows through the carbon dioxide recovery pipeline 72 from the valve 14, and goes to the compressor 63. At this time, a carbon dioxide sensor and a flow meter (not shown) may also be arranged on the carbon dioxide recovery pipeline 72 to grasp the amount and concentration of the desorbed carbon dioxide.

[0084] Furthermore, the desorbed carbon dioxide is compressed by the compressor 63 and filled in the tank 64 in a prescribed state (liquid or gas) and buried underground or the like. Thereby, the carbon dioxide in the gas such as the atmosphere is recovered by the carbon dioxide recovery device 1.

[0085] In addition, as Figure 1 shown, a form may also be adopted in which a switching valve 65 is provided on the carbon dioxide recovery pipeline 72 between the vacuum pump 62 and the compressor 63. The switching valve 65 is configured to be able to selectively switch the state in which the port 65c communicates with the port 65b and the state in which the port 65a communicates with the port 65c. This switching is performed by the control unit 50.

[0086] The port 65c is connected to the side of the vacuum pump 62 of the carbon dioxide recovery pipeline 72, and the port 65b is connected to the side of the compressor 63 of the carbon dioxide recovery pipeline 72. The port 65a is connected to the second exhaust pipeline 73 connected to the exhaust pipeline 71.

[0087] For example, the following form may also be adopted: at the initial stage of driving of the carbon dioxide recovery device 1 or the like, before the amount and concentration of the carbon dioxide flowing in the carbon dioxide recovery pipeline 72 reach a prescribed value, the switching valve 65 is used to make the gas flowing through the carbon dioxide recovery pipeline 72 flow to the second exhaust pipeline 73 and be discharged to the outside of the carbon dioxide recovery device 1 from the exhaust pipeline 71. Thereby, when the concentration of carbon dioxide is low and other gases are mixed in, it is possible to exhaust without guiding the gas to the compressor 63.

[0088] (Regarding the number of modules 11 in the module unit 10)

[0089] As described above, during the driving of the carbon dioxide recovery device 1, the module 11 alternately performs the adsorption process and the desorption process according to the instruction of the control unit 50.

[0090] In the carbon dioxide recovery device 1 of the present embodiment, the 16 modules 11 included in the module unit 10 are driven such that the phases of the operation cycles in each module 11 are equally staggered. Therefore, at any point in time during the operation of the carbon dioxide recovery device 1, at least one module 11 performs the desorption process, and the other modules 11 perform the adsorption process.

[0091] (Setting regarding the number of modules 11)

[0092] Figure 4 FIG. is a diagram for explaining the operation states and output ratios of the adsorption device and the desorption device in the case where there is 1 module 11 in the module unit 10.

[0093] Here, the adsorption device refers to the adsorption device participating in the adsorption process of the module 11, which is the fan 61 in the present embodiment. The desorption device refers to the desorption device participating in the desorption process of the module 11, which includes a vacuum pump 62 in the present embodiment, and more specifically, a compressor 63 and a heat pump 80.

[0094] Figure 4 The diagram shown in (a) shows the operation cycles of the adsorption device and the desorption device in the case where there is 1 module 11 in the module unit 10. Figure 4 The diagram shown in (b) shows Figure 4 The relationship between the operation state and the output ratio of the adsorption device during the operation cycle shown in (a). Figure 4 The diagram shown in (c) shows Figure 4 The relationship between the operation state and the output ratio of the desorption device during the operation cycle shown in (a). In Figure 4 (a), the vertical axis represents the cycle, 1 represents the adsorption process, 2 represents the desorption process, and the horizontal axis represents time. In Figure 4 (b) and (c), the vertical axis represents the output ratio, and the horizontal axis represents time. In the output ratio on the vertical axis, the total output during the driving of each device in each process of 1 module 11 is 1.

[0095] The module 11 performs the adsorption process for x seconds and the desorption process for y seconds. In Figure 4 and as shown below Figure 5 and Figure 6 , as an example, an example where x = 5669 seconds and y = 967 seconds is shown.

[0096] When the module unit 10 includes 1 module 11, during the adsorption process of the module 11, the fan 61 is driven, while the vacuum pump 62, the compressor 63, and the heat pump 80 are not driven. Therefore, as Figure 4 shown in (b) and (c), the output ratio of the adsorption device during the adsorption process is 1, and the output ratio of the desorption device is 0.

[0097] In addition, in the module unit 10 having one module 11, during the desorption process in the module 11, the vacuum pump 62, the compressor 63, and the heat pump 80 are driven, while the fan 61 is not driven. Therefore, as Figure 4 shown in (b) and (c), the output ratio of the adsorption device during the desorption process is 0, and the output ratio of the desorption device is 1.

[0098] That is, when there is one module 11 in the module unit 10, the adsorption device (fan 61) and the desorption device (vacuum pump 62, compressor 63, and heat pump 80) are repeatedly driven and stopped each time the process is switched, and the operation is intermittent. Therefore, there may be a decrease in the drive efficiency caused by the drive / stop of the adsorption device and the desorption device, as well as a decrease in the durability of each device.

[0099] Figure 5 It is a diagram for explaining the operation states and output ratios of the adsorption device and the desorption device when there are two modules 11 in the module unit 10.

[0100] Figure 5 The diagram shown in (a) shows the operation cycles of the adsorption device and the desorption device when there are two modules 11 in the module unit 10. Figure 5 The diagram shown in (b) shows Figure 5 the relationship between the operation state and the output ratio of the adsorption device during the operation cycle shown in (a). Figure 5 The diagram shown in (c) shows Figure 5 the relationship between the operation state and the output ratio of the desorption device during the operation cycle shown in (a). In Figure 5 (a), the vertical axis represents the cycle, 1 is the adsorption process, 2 is the desorption process, and the horizontal axis represents time. In Figure 5 (b) and (c), the vertical axis represents the output ratio, and the horizontal axis represents time. In the output ratio on the vertical axis, when all two modules 11 are performing the adsorption process, the total output of each device in the case of performing the desorption process is 1.

[0101] As Figure 5 shown in (a), the two modules 11 are driven with a phase shift of 1 / 2 in the operation cycle.

[0102] As Figure 5 shown in (b) and (c), when both two modules 11 are performing the adsorption process, the output ratio of the adsorption device is 1, and the output ratio of the desorption device is 0. When one module 11 (for example, the #1 module 11) is performing the desorption process and the other (for example, the #2 module 11) is performing the adsorption process, the output ratio of the adsorption device is 0.5, and the output ratio of the desorption device is 0.5.

[0103] Therefore, compared with the case where there is 1 module 11 in the module unit 10, when there are 2 modules 11, the variation range of the output of each device caused by the switching of the operation states of each module is smaller. In addition, although there is a variation in the output ratio of the adsorption device, it is continuously driven. On the other hand, the desorption device is driven intermittently.

[0104] Figure 6 It is a diagram showing the operation states and output ratios of the adsorption device and the desorption device when there are 16 modules 11 in the module unit 10.

[0105] Figure 6 The diagram shown in (a) shows the operation cycles of the adsorption device and the desorption device when there are 16 modules 11 in the module unit 10. Figure 6 The diagram shown in (b) shows Figure 6 The relationship between the operation state and the output ratio of the adsorption device during the operation cycle shown in (a). Figure 6 The diagram shown in (c) shows Figure 6 The relationship between the operation state and the output ratio of the desorption device during the operation cycle shown in (a). In Figure 6 (a), the vertical axis is the cycle, 1 is the adsorption process, 2 is the desorption process, and the horizontal axis is time. In Figure 6 (b) and (c), the vertical axis is the output ratio, and the horizontal axis is time. In the output ratio on the vertical axis, the total output of the adsorption device when all 16 modules 11 perform the adsorption process simultaneously and the total output of the desorption device when performing the desorption process are 1.

[0106] In Figure 6 the example shown, as Figure 6 shown in (a), among the 16 modules 11, the state where 2 modules 11 perform the desorption process and the state where temporarily 3 modules 11 perform the desorption process during the process switching of the module 11 alternate repeatedly. As Figure 6 shown in (b) and (c), during the period when 2 modules 11 perform the desorption process, the output ratio of the adsorption device becomes 0.875, and the output ratio of the desorption device becomes 0.125. In addition, during the period when 3 modules 11 perform the desorption process, the output ratio of the adsorption device is 0.8125, and the output ratio of the desorption process is 0.1875.

[0107] At this time, both the adsorption device and the desorption device are continuously driven even though there is a variation in the output ratio. Therefore, the driving of the adsorption device and the desorption device is more stable. In addition, at this time, the maximum output ratio of the adsorption device and the desorption device is smaller than the maximum output ratio when all 16 modules 11 are driven in the same phase, and the performance required for each device becomes lower. Thus, the cost of each device can be suppressed, and the manufacturing cost of the carbon dioxide recovery device 1 can be suppressed.

[0108] Furthermore, at this time, the variation range of the outputs of the adsorption device and the desorption device caused by the switching of the operation states of the respective modules 11 becomes further smaller, and each device can be driven more stably.

[0109] Thus, by making the number of modules 11 included in the module unit 10 equal to or more than a specified number and equally staggering the phases of the operation cycles of the respective modules 11, the adsorption device and the desorption device can be continuously driven.

[0110] In the carbon dioxide recovery device 1, when the time required for the adsorption process is set to x seconds and the time required for the desorption process is set to y seconds, and when driving while equally staggering the phases of a plurality of modules 11 in one module unit 10, at any time point in the operation cycle, the number N1 of modules 11 that perform the desorption process is obtained by the following (Equation 1).

[0111] [Equation 1]

[0112] .

[0113] By making the number of modules 11 in the module unit 10 equal to or more than N1 that satisfies this (Equation 1), the adsorption device (fan 61) and the desorption device (vacuum pump 62, compressor 63, heat pump 80) can be continuously driven, and the driving efficiency and durability of each device under intermittent driving can be improved.

[0114] In the present embodiment, as described above, the time x required for the adsorption process is 5669 seconds, and the time y required for the desorption process is 967 seconds. If substituted into the above (Equation 1), then N1 > 6.8. Since the number of modules 11 is a positive integer, the number of modules 11 in the module unit 10 is preferably set to 7 or more. In the carbon dioxide recovery device 1 of the present embodiment, the module unit 10 includes 16 modules 11, which satisfies the above (Equation 1).

[0115] Figure 7 is a graph showing Figures 4 to 6 in an example of the operation cycle shown in the relationship between the output ratios of the adsorption device and the desorption device, the difference between the output ratios of the upper limit and the lower limit of the operation of each device, that is, the variation range, and the number of modules.

[0116] Figure 7 (a) shows the relationship between the output ratio of the adsorption device and the number of modules (the number of modules 11 included in the module unit 10), and the relationship between the difference between the output ratios of the upper limit and the lower limit of the operation of the adsorption device, that is, the variation range, and the number of modules. Figure 7 (b) shows the relationship between the output ratio of the desorption device and the number of modules, and the relationship between the difference between the output ratios of the upper limit and the lower limit of the operation of the desorption device, that is, the variation range, and the number of modules. In Figure 7In the graphs shown in (a) and (b), the vertical axis on the left represents the output ratio, the horizontal axis represents the number of modules, and the vertical axis on the right represents the difference in output ratios.

[0117] The so-called upper operation limit corresponds to the total output of each device at each number of modules, and the so-called lower operation limit corresponds to the minimum output of each device at each number of modules.

[0118] As Figure 7 shown, when there is 1 module 11, the difference in output ratios between the upper operation limit and the lower operation limit, that is, the variation range, of the adsorption device and the desorption device is large. However, as the number of module 11 increases, the variation range tends to become smaller.

[0119] In Figure 7 the graph shown, when the number of module 11 is 7, the output ratios of the upper operation limit and the lower operation limit of the adsorption device decrease. This is because in the above (Equation 1), N1 > 6.8. When the number of module 11 is set to 7, at any time point in the operation cycle, at least one module 11 is in the state of performing the desorption process. In addition, when the number of module 11 is 7, the output ratios of the upper operation limit and the lower operation limit of the desorption device increase. This is because when the number of module 11 is set to 7, since N1 > 6.8, strictly speaking, during the operation cycle, there is a part of the time when 2 module 11 perform the desorption process.

[0120] In summary, from the viewpoints of stable driving of the adsorption device and the desorption device, improvement of driving efficiency and durability, and reduction of the cost of each device, the number of module 11 included in the module unit 10 is preferably set to N1 or more.

[0121] In addition, since the fan as the adsorption device can be continuously operated and each module 11 is connected in parallel to the exhaust pipeline 71, a fan with an appropriate flow rate can be used, and the driving efficiency can be improved. In addition, a vacuum pump or the like as the desorption device can also be continuously driven, and the driving efficiency can be improved.

[0122] In addition, as described above, by setting the number of modules to N1 or more, at least one module 11 performs the desorption process in the module unit 10. Thereby, the maximum output of each device can be reduced. For example, when the number of modules is set to N (N ≥ N1, N is an integer) and the number of module 11 performing the desorption process is set to m (m ≥ 1, m is an integer), regarding the fan as the adsorption device, if the maximum output when all N modules perform the adsorption process is set to 1, the output in the output ratio can be reduced by an amount of m × 1 / N.

[0123] As described above, in this embodiment, when the module unit 10 includes 16 modules 11 and the phases of the operation cycles are equally shifted to drive the modules, it is preferably controlled such that at any given time, any two modules 11 perform the desorption process. At this time, it is preferably controlled such that the phases of the operation cycles of eight modules 11 are equally shifted to drive the modules, and among the eight modules 11, at any given time, any one module 11 performs the desorption process. As for the module unit 10 as a whole, it is controlled such that among the 16 modules 11, at any given time, any two modules 11 perform the desorption process. In addition, there may be a state where two modules 11 among the eight modules 11 perform the desorption process. Thus, there may be a state where, for example, as shown in the foregoing Figure 6 example, three modules 11 perform the desorption process.

[0124] (Regarding waste heat recovery by a heat pump)

[0125] Next, a case where heat energy is transferred between multiple modules 11 by a heat pump 80 in a carbon dioxide recovery device based on the direct air capture (DAC) technology will be described.

[0126] Generally, a large amount of heat energy is required when the module 11 performs the desorption process. Therefore, it is desirable to supply heat energy to the module 11 with less power.

[0127] Thus, in the carbon dioxide recovery device 1, multiple modules 11 are provided, and the phases of the operation cycles of each module 11 are equally shifted to drive the modules. Modules that are at the start of the desorption process that requires heat energy or in the first half of the desorption process are combined with modules that are in the second half of the desorption process that does not require heat energy or in the first half of the adsorption process in the heat transfer medium circuit of the heat pump 80, and the number of modules 11 is set in such a way that heat energy can be recovered and supplied efficiently.

[0128] Figure 8 FIG. is a diagram for explaining the recovery and supply of heat energy between two modules 11.

[0129] In Figure 8 the graphs shown in (a) to (c), the vertical axis represents temperature and the horizontal axis represents time. Figure 8 (a) shows the relationship between the operation of the No. 1 (#1) module 11 and temperature, Figure 8 (b) shows the relationship between the operation of the No. 2 (#2) module 11 and temperature, Figure 8 (c) shows the relationship between the operation of the No. n (#n) module 11 and temperature. In addition, in Figure 8 , the adsorption process is shown as S1 and the desorption process is shown as S2.

[0130] InFigure 8 In this case, the first half of the adsorption process of the No. 1 (#1) module 11 corresponds to and is paired with the first half of the desorption process of the No. 2 (#2) module 11. However, the nth (#n) module is not paired with either the No. 1 (#1) or No. 2 (#2) module 11.

[0131] In the carbon dioxide recovery device 1, let the time required for the adsorption process of the module 11 be x seconds, the time required for the desorption process be y seconds, and for the paired modules, the allowable time difference z seconds between the start time of the adsorption process of the module (the No. 1 module in Figure 8 this case) 11 and the start time of the desorption process of the module (the No. 2 module in Figure 8 this case) 11. The number N2 of modules with one or more pairs of such paired modules 11 is a positive integer multiple of the number N0 obtained using the following (Equation 2). Additionally, this number N2 is 2 or more, preferably 3 or more.

[0132] [Equation 2]

[0133] .

[0134] By satisfying the above (Equation 2), the heat energy of the module (No. 1 module) 11 that has completed the desorption process and started the adsorption process can be recovered by the heat pump 80, and the heat energy can be supplied to the module starting the desorption process (No. 2 module), thereby reducing the electricity required for heat energy supply.

[0135] Figure 9 is a graph showing the relationship between the time error Z0 and the number of modules. In Figure 9 this case, the vertical axis is the time error Z0 (seconds), and the horizontal axis is the number N0 (pieces) of the modules 11 in (Equation 2). The curve shown as a solid line in Figure 9 is Z0 = |(x + y) / N0 - y| on the left side of (Equation 2) in the case of x = 5669 seconds and y = 967 seconds.

[0136] In the case of x = 5669 seconds and y = 967 seconds, assuming the allowable time difference z = 60 seconds, the number N0 of modules 11 that satisfy (Equation 2) is also as Figure 9 shown, N0 = 7, and the optimal number of modules in the module unit 10 is set to a multiple of 7.

[0137] Additionally, in the case of x = 5669 seconds and y = 967 seconds, when N0 = 7, the time error Z0 is the smallest. So, depending on the allowable time difference z, the number N0 of modules is preferably 7 - 9, and the number N2 of modules is preferably set to its integer multiples, namely 7 - 9, 14 - 18, 21 - 27, etc.

[0138] In the present embodiment, let N0 = 8 and N2 = N0 × 2, and 16 modules 11 are provided. Thus, in this case, the allowable time difference z is z ≧ 137.5 seconds.

[0139] The smaller the allowable time difference z is, the shorter the operation cycle time of the entire carbon dioxide recovery device 1 can be, so it is preferable. The allowable time difference z can also be appropriately preset to a specified value according to the number of modules 11 and their usage environment, etc., in order to drive the carbon dioxide recovery device 1 efficiently.

[0140] Figure 10 It is a diagram showing the number of modules and the operations of each module. In Figure 10 (a) and (b), the vertical axis is the cycle, and the horizontal axis is the time. Figure 10 (a) shows an example where the number of modules 11 in the module unit 10 is 3, Figure 10 (b) shows an example where the number of modules 11 in the module unit 10 is 7. In addition, in Figure 10 , it shows that the time x required for the adsorption process is 5669 seconds, and the time y required for the desorption process is 967 seconds.

[0141] As Figure 10 (a) shows, when there are 3 modules 11 and the phases of the operation cycles of each module are equally shifted to drive, there are no modules in the first half of the adsorption process corresponding and paired with the modules in the first half of the desorption process. Therefore, the recovered heat energy cannot be moved to the module 11 in the first half of the desorption process that requires heat energy.

[0142] In contrast, as Figure 10 (b) shows, when there are 7 modules 11 and the phases of the operation cycles of each module are equally shifted to drive, for example, the first half of the adsorption process of the 1st (#1) module 11 corresponds to the first half of the desorption process of the 2nd (#2) module 11, and the first half of the adsorption process of the 2nd (#2) module 11 corresponds to the first half of the desorption process of the 3rd (#3) module.

[0143] By adopting such a structure, the unnecessary heat energy can be recovered from the module 11 starting the adsorption process and efficiently supplied to the module 11 starting the desorption process, which requires heat energy. Thus, the heat pump 80 can be driven with a higher coefficient of performance (COP), and the power consumed in the supply of heat energy can be reduced. In addition, COP is the ratio of the heat output to the input heat, which is equivalent to the total heat received by the module that has started the desorption process divided by the power of the compressor of the heat pump 80. COP represents the efficiency of the heat pump 80, and the higher the value of COP, the more output can be obtained with less input.

[0144] The heat transfer medium circuit of the heat pump 80 for realizing the recovery and supply of high-efficiency heat energy as described above is as follows Figure 11 as shown below.

[0145] Figure 11 FIG. is a diagram showing the heat transfer medium circuit of the heat pump 80 in the present embodiment.

[0146] In Figure 11 order to facilitate understanding, the shape of the module and the like are simplified and only the heat exchange section 16 (adsorbent 20) is shown. The heat pump 80 includes a compressor 81, a plurality of pipes 82, switching valves 83 (83-1 to 83-4), etc. The pipes 82 are appropriately connected to the switching valves 83.

[0147] In Figure 11 order to facilitate understanding, the same symbols are used to indicate the structures common to each module, and numbers such as No. 1 (#1) and No. 2 (#2) are appropriately used for explanation.

[0148] This heat transfer medium circuit is a circuit provided in the carbon dioxide recovery device 1 by the heat pump. The carbon dioxide recovery device 1 includes a plurality of modules 11 for carbon dioxide recovery. The plurality of modules 11 for carbon dioxide recovery include an adsorbent 20 for adsorbing and desorbing carbon dioxide, and perform an adsorption process of adsorbing carbon dioxide to the adsorbent 20 and a desorption process of desorbing the adsorbed carbon dioxide; the heat pump supplies heat energy to the module 11. This heat transfer medium circuit includes: a plurality of heat exchange sections 16; a compressor 81, which is a compressor for compressing the heat transfer medium flowing in the heat exchange section 16; a main path, which serially connects the compressor 81 and the plurality of heat exchange sections 16 to circulate the heat transfer medium; and a reversing mechanism, which switches the heat transfer medium flowing in the main path in the first direction to the second direction opposite to the first direction. The heat exchange section 16 is respectively arranged in the module 11, and the heat transfer medium circuit 16 can transfer at least a part of the heat energy absorbed by the heat transfer medium in one of the heat exchange sections 16 to the other heat exchange section 16 between the two heat exchange sections 16.

[0149] In addition, the heat transfer medium circuit is a circuit provided in the heat pump that supplies heat energy to the module 11 in the carbon dioxide recovery device 1 having a plurality of modules 11 for carbon dioxide recovery as described above. It has three or more heat exchange sections 16, a compressor, i.e., a compressor 81, that compresses the heat transfer medium flowing in the heat exchange section 16, and a main path that serially connects the compressor 81 and the plurality of heat exchange sections 16 to circulate the heat transfer medium. The heat exchange sections 16 are respectively arranged in the module 11, and each heat exchange section 16 is provided with a bypass section that selectively bypasses the inflow of the heat transfer medium to the heat exchange section 16 where no heat energy moves. Between two heat exchange sections 16, at least a part of the heat energy absorbed by the heat transfer medium in one heat exchange section 16 is moved to the other heat exchange section 16.

[0150] In each module, there are provided a hose 88 for the heat transfer medium to flow in the heat exchange section 16, an expansion valve 86 provided on the hose 88, a switching valve 85 for switching the inflow of the heat transfer medium to the heat exchange section 16, a bypass 87 connecting the port 85b of the switching valve 85 and the pipe 82, a branch 89 connecting the bypass 87 and the pipes 82, 88, etc. In addition, only in the Nth (#N) module, the expansion valve 86 is located on the hose 88 on the port 85c side of the switching valve 85, and in other modules, it is provided on the hose 88 on the branch 89 side.

[0151] The pipe 82 connected to the compressor 81 is connected to a plurality of switching valves 83, and is designed such that by switching the communication of the switching valves 83, the traveling direction and the flow path of the heat transfer medium in the heat transfer medium circuit can be changed.

[0152] The pipe 82 forms a main path for the heat transfer medium to flow. In addition, the switching valve 83 and a part of the pipe 82-2 connected to the pipe 82 as the main path via the switching valve 83 are a reversing mechanism for reversing the flow path.

[0153] The opening and closing of the switching valves 83, 85, the opening and closing of the expansion valve 86, and the control of the branch, etc. are performed by the control unit 50.

[0154] Hereinafter, the movement of heat energy caused by the heat transfer medium circuit of the heat pump 80 in the present embodiment will be described. In the present embodiment, for the sake of easy understanding, as an example, the following example is cited for description: When the No. 1 (#1) module finishes the desorption process and starts the adsorption process, the No. 2 (#2) module starts the desorption process, and when the No. 2 (#2) module finishes the desorption process and starts the adsorption process, the No. 3 (#3) module starts the desorption process. In this way, the desorption process is sequentially performed starting from the module with a smaller number, and heat energy mainly moves between two adjacent modules, such as from the nth to the (n + 1)th. In addition, the two modules for heat energy movement are not limited to adjacent positions in the heat transfer medium circuit.

[0155] Figure 12 This is a diagram showing an example of the flow of the heat transfer medium in the heat transfer medium circuit of the heat pump 80. Figure 12 (a) is a graph showing the temperature and time of the adsorbent 20 of the #2 and #3 modules. The vertical axis represents temperature and the horizontal axis represents time. In Figure 12 (a), the first half of the adsorption process of the #2 adsorbent 20 corresponds to the first half of the desorption process of the #3 adsorbent 20. Figure 12 (b) shows the flow path and direction of the heat transfer medium during the corresponding time period. For easy understanding, the pipes through which the flowing heat transfer medium passes are shown as solid lines, and the pipes through which the non-flowing heat transfer medium passes are shown as dashed lines. It is assumed that modules other than the #2 and #3 modules perform the adsorption process.

[0156] In addition, in Figure 12 and the following Figure 13 , an example in which N modules are arranged in one module unit 10 will be described. It is assumed that N is a positive integer and satisfies the aforementioned (Equation 2) (N = N2).

[0157] As Figure 12 shown, in the first half of the adsorption process of the #2 module and the first half of the desorption process of the #3 module, the heat transfer medium that is compressed by the compressor 81 of the heat pump 80 and becomes high temperature passes through the pipe 82 and the switching valve 83 and flows in the direction of the arrow shown in the figure, that is, the first flow direction.

[0158] The heat transfer medium first reaches the #N module. The heat transfer medium flows from the branch 89 to the bypass 87, from the port 85b of the switching valve 85 to the port 85a, goes to the pipe 82, and goes to the next unillustrated #(N - 1) module.

[0159] Therefore, it does not flow within the #N heat exchange section 16, and the #N adsorbent 20 is not heated and remains at room temperature.

[0160] The flow path of the heat transfer medium in the unillustrated #(N - 1) to #4 modules is the same as that of the #N module.

[0161] The heat transfer medium that has reached the #3 module goes from the branch 89 to the hose 88, flows within the heat exchange section 16 to heat the adsorbent 20. And it flows from the port 85c of the switching valve 85 to the port 85a, passes through the pipe 82 and goes to the #2 module. At this time, the temperature of the heat transfer medium drops compared to before reaching the #3 module.

[0162] The heat transfer medium that reaches the No. 2 (#2) module expands due to the opening of the expansion valve 86 and flows in the hose 88 in the heat exchange section 16 in a state where the temperature drops. At this time, the No. 2 (#2) adsorbent 20 becomes high temperature due to the heat energy supplied in the desorption process. The heat transfer medium flowing in the hose 88 of the No. 2 (#2) heat exchange section 16 absorbs the surrounding heat, and the temperature of the adsorbent 20 drops. Since the heat transfer medium continuously flows in the heat exchange section 16 while absorbing heat, the adsorbent 20 drops to the normal temperature (25 °C) suitable for the adsorption process. And the heat transfer medium whose temperature rises due to heat absorption flows from the port 85c of the switching valve 85 to the port 85a, passes through the pipe 82, and goes to the No. 1 (#1) module.

[0163] In the No. 1 (#1) module, similarly to the Nth module, the heat transfer medium flows from the branch 89 through the bypass 87 to the switching valve 85, flows from the port 85b of the switching valve 85 to the port 85a, and goes to the pipe 82. And it returns to the compressor 81 through the pipe 82, the switching valve 83, etc.

[0164] As described above, since the heat transfer medium flows in the heat transfer medium circuit, the No. 2 (#2) adsorbent 20 is cooled to the temperature suitable for the adsorption process, and the No. 3 (#3) adsorbent 20 is heated to the temperature suitable for the desorption process (90 °C). In addition, in modules other than No. 2 and No. 3, the adsorbent 20 is not heated and maintains the normal temperature.

[0165] This transfer of heat energy also occurs between other adjacent modules such as between the No. 3 (#3) and No. 4 (#4) modules, not just between the above-mentioned No. 2 (#2) and No. 3 (#3) modules.

[0166] The recovery and supply of heat energy between adjacent modules 11 are carried out as described above. Next, the recovery and supply of heat energy between non-adjacent modules 11 are carried out as follows.

[0167] Figure 13 It is a diagram showing an example of the flow of the heat transfer medium in the heat transfer medium circuit of the heat pump 80. Figure 13 (a) is a graph showing the temperature and time of the adsorbent 20 of the Nth (#N) and No. 1 (#1) modules, with the vertical axis being the temperature and the horizontal axis being the time. In Figure 13 (a), the first half of the adsorption process of the Nth (#N) adsorbent 20 corresponds to the first half of the desorption process of the No. 1 (#1) adsorbent 20. Figure 13 (b) shows the flow path and direction of the heat transfer medium in the corresponding time period. For easy understanding, the pipes through which the heat transfer medium flows are shown as solid lines, and the pipes through which the heat transfer medium does not flow are shown as dashed lines. In addition, it is assumed that modules other than the Nth (#N) and No. 1 (#1) modules perform the adsorption process.

[0168] At the time when the adsorption process starts in the Nth (#N) module, the control unit 70 switches the connection state of the switching valves 83 (83-1 to 83-4) provided on the pipe 82 of the heat pump 80, temporarily making the flow path and the flow direction of the heat transfer medium in the heat transfer medium circuit opposite to those before, that is, the second flow direction.

[0169] As Figure 13 (b) shows, first, the heat transfer medium compressed by the compressor 81 and thus becoming high-temperature flows from the pipe 82 from the port 83b of the switching valve 83-1 to the port 83a, passes through the pipe 82-2, flows from the port 83a of the switching valve 83-3 to the port 83b, and passes through the pipe 82-2 to go to the 1st (#1) module.

[0170] The heat transfer medium flows from the port 85a of the switching valve 85 of the 1st (#1) module to the port 85c and flows in the hose 88 in the heat exchange section 16. Thereby, the adsorbent 20 is heated to a temperature (90 °C) suitable for the desorption process. At this time, the temperature of the heat transfer medium drops compared to before reaching the 1st (#1) module.

[0171] The heat transfer medium leaves the 1st (#1) module after passing through the branch 89 to go to the pipe 82. And the heat transfer medium passes through the pipe 82 and reaches the 2nd (#2) module. The heat transfer medium flows from the port 85a of the switching valve 85 of the 2nd (#2) module to the port 85b, passes through the bypass 87, flows through the branch 89 to go to the pipe 82, and goes to the 3rd (#3) module. That is, the heat transfer medium does not flow in the heat exchange section 16 of the 2nd (#2) module, and the adsorbent 20 maintains room temperature.

[0172] In the 3rd (#3) to the N-1th modules (not shown), etc., the heat transfer medium also does not flow in the heat exchange section 16 and passes through the switching valve 85 and the bypass 87 to go to the next module. Thus, in the 3rd (#3) to the N-1th modules, the adsorbent 20 maintains room temperature.

[0173] The heat transfer medium reaching the Nth (#N) module expands due to the opening and pressure reduction of the expansion valve 86 provided on the hose 88, and the temperature drops. The heat transfer medium flows in the hose 88 in the heat exchange section 16 of the Nth (#N) module in a low-temperature state, absorbs heat from the surroundings, and lowers the temperature of the adsorbent 20. The heat transfer medium whose temperature has risen due to heat absorption flows from the hose 88 through the branch 89 to go to the pipe 82 and goes to the compressor 81. And it flows from the port 83b of the switching valve 83-2 to the port 83a, passes through the pipe 82 and goes to the switching valve 83-4. And it flows from the port 83a of the switching valve 83-4 to the port 83b, passes through the pipe 82 and enters the compressor 81.

[0174] As described above, the control unit 50 switches the connection and the like of the switching valves 83 and 85 provided on the pipe 82 of the heat transfer medium circuit of the heat pump 80. Thereby, in the heat transfer medium circuit, the heat transfer medium can be temporarily reversed, and the recovery and supply of heat energy between non-adjacent modules 11 can be performed efficiently.

[0175] In addition, when the desorption process of the No. 1 (#1) module 11 ends, by the control of the control unit 50, the connection and the like of the switching valve 83 are switched, and the flow direction of the heat transfer medium in the heat transfer medium circuit of the heat pump 80 is restored to the original direction, that is, the first flow direction. And the heat energy of the No. 1 (#1) module is recovered by the heat transfer medium and supplied to the heat energy of the No. 2.

[0176] In summary, by adopting the heat transfer medium circuit of the present embodiment and the waste heat recovery type heat pump 80 having the heat transfer medium circuit, the heat energy that is not required in a certain module 11 can be efficiently moved to the module 11 that requires heat energy. In addition, according to the carbon dioxide recovery device 1 of the present embodiment, the unnecessary heat can be recovered by the waste heat recovery type heat pump 80, and the power consumed in the supply of heat energy during the desorption process of each module 11 can be reduced.

[0177] In addition, according to the present embodiment, the heat pump can be driven with a higher COP, and the power consumed in the supply of heat energy can be reduced.

[0178] (Modified form)

[0179] It is not limited to the embodiment described above, and various modifications or changes can be made, and they are also within the scope of the present invention.

[0180] Regarding the heat transfer medium circuit of the heat pump 80, the following form can also be adopted.

[0181] Figure 14 It is a diagram showing an example of the heat transfer medium circuit of the heat pump 80 when the number of modules is N×2.

[0182] When the number of modules is N×2, as Figure 14 shown, the heat transfer medium circuit of the heat pump 80 is adopted in a form having a bank 1 and a bank 2, the bank 1 includes N modules 11, and the bank 2 includes N modules 11. And in the heat transfer medium circuit of the heat pump 80, it is configured that the nth (#n - 1) module 11 of the bank 1 and the nth (#n - 2) module 11 of the bank 2 operate in the same phase.

[0183] The number N is an integer multiple of the number N0 obtained by using the foregoing (Equation 2). In addition, it is preferably satisfied with the foregoing (Equation 1).

[0184] In addition, a plurality of switching valves 83 (83-1 to 83-4) and pipes 82-2 are provided on the heat transfer medium circuit. By controlling the switching of the connections of these switching valves 83, as described above, Figure 12 and Figure 13 shown, the direction of flow of the heat transfer medium can be switched, etc.

[0185] By adopting such a configuration, even when the number of modules 11 increases, a single compressor 81 can be used to efficiently recover and supply thermal energy, and the power consumption required for supplying thermal energy in the desorption process of the module 11 can be suppressed.

[0186] In addition, regarding the flow path (hose) of the heat transfer medium flowing in the heat exchange section 16 of the module 11, the following form is preferably adopted.

[0187] Figure 15 is a diagram showing an example of the flow of the heat transfer medium in the heat exchange section 16.

[0188] In Figure 15 as an example, the case where the high-temperature heat transfer medium flows in from the compressor 81 of the heat pump 80 is shown.

[0189] The high-temperature heat transfer medium flows from the port 85a of the switching valve 85 to the port 85b and flows into a hose (not shown) inside the layer 17 from the inflow section 17a provided on one side 171 of the layer 17. And, as Figure 15 shown, it is depicted in a U shape, flows out from the outflow section 17b provided on the same side 171, and goes to the next module through the pipe 82. In this way, by setting the inlet and outlet of the heat transfer medium and arranging the hose so that the heat transfer medium flows in a U shape in the layer 17, the length of the bypass 87 connecting from the port 85b of the switching valve 85 to the pipe 82 can be minimized. As a result, the structure of the heat transfer medium can be simplified, and the loss of thermal energy of the heat transfer medium caused by flowing in a long flow path can be suppressed.

[0190] In addition, the present embodiment and the modified forms can be used in appropriate combination, but detailed description is omitted. Further, the present invention is not limited by the embodiments described above, etc.

[0191] Reference Numerals

[0192] 1 Carbon dioxide recovery device

[0193] 10 Module unit

[0194] 11 Module

[0195] 12 Valve

[0196] 13 Valve

[0197] 14 Valve

[0198] 16 Heat exchange section

[0199] 20 Adsorbent

[0200] 50 Control section

[0201] 61 Fan

[0202] 62 Vacuum pump

[0203] 63 Compressor

[0204] 64 Tank

[0205] 80 Heat pump

[0206] 81 Compressor

[0207] 82 Pipe

[0208] 83 Switching valve

Claims

1. A heat transfer medium circuit, comprising: a plurality of heat exchange sections; a compressor that compresses the heat transfer medium flowing in the heat exchange sections; a main path that serially connects the compressor and the plurality of heat exchange sections to circulate the heat transfer medium; and a reversing mechanism that switches the heat transfer medium flowing in the first flow direction in the main path to a second flow direction opposite to the first flow direction; and between two of the heat exchange sections, at least a part of the heat energy absorbed by the heat transfer medium in one of the heat exchange sections is transferred to the other heat exchange section.

2. The heat transfer medium circuit according to claim 1, wherein, The heat transfer medium circuit includes three or more of the heat exchange sections, and for each of the heat exchange sections, a bypass section is provided, and the bypass section selectively bypasses the inflow of the heat transfer medium to the heat exchange section where heat energy transfer does not occur.

3. The heat transfer medium circuit according to claim 1, wherein, The reversing mechanism is a reversing path having a plurality of pipes, and the plurality of pipes connect the upstream side and the downstream side via a switching valve across the compressor in the main path.

4. The heat transfer medium circuit according to claim 1, wherein, The heat transfer medium circuit includes an expansion valve that expands the heat transfer medium flowing into each of the heat exchange sections, and when the heat transfer medium flows into the heat exchange section as the heat absorption object, the heat transfer medium is expanded to lower the temperature.

5. A heat pump, comprising the heat transfer medium circuit according to any one of claims 1 to 4.

6. A carbon dioxide recovery device, comprising: the heat pump according to claim 5; and a plurality of carbon dioxide recovery modules, each having an adsorbent for adsorbing and desorbing carbon dioxide, and performing an adsorption process and a desorption process, the adsorption process being to adsorb carbon dioxide to the adsorbent, and the desorption process being to desorb the carbon dioxide adsorbed to the adsorbent; and the heat exchange sections are respectively disposed in the carbon dioxide recovery modules, and the heat pump transfers heat energy between the plurality of carbon dioxide recovery modules.

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