Carbon dioxide capture equipment

Abstract

To provide a configuration which allows rapid startup even when the outside air temperature is low in a carbon dioxide recovery apparatus that performs a desorption process and an adsorption process through thermal control by a heat source unit of a heat pump type.SOLUTION: A heat exchange device 70 of a carbon dioxide recovery apparatus 1 includes a heat source unit 81 of a heat pump type that heats hot water and cools cold water, a heat source high-temperature water circuit 85 that includes a hot water tank 83 that stores hot water heated by the heat source unit 81 and circulates hot water between the hot water tank 83 and the heat source unit 81, a heat source low-temperature water circuit 86 that includes a cold water tank 82 that stores cold water cooled by the heat source unit 81 and circulates cold water between the cold water tank 82 and the heat source unit 81, a hot water supply line 96 that connects the heat source high-temperature water circuit 85 and the heat source low-temperature water circuit 86, and a control device 90 that controls the supply of hot water from the heat source high-temperature water circuit 85 to the heat source low-temperature water circuit 86.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a carbon dioxide capture device. [Background technology]

[0002] Conventionally, in the technology for extracting predetermined components from gas, a technology for increasing the temperature using a heating device such as an electric heater at the time of startup has been known. This type of technology is described, for example, in Patent Document 1. Patent Document 1 describes a technology for increasing the temperature of a desulfurization catalyst layer by an electric heater at the time of startup of a desulfurization reactor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-147903 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, a heat source such as a heat pump is used in a carbon dioxide recovery device that sucks a gas such as air containing carbon dioxide into a module that holds an adsorbent, causes the gas to be adsorbed by the adsorbent, and then reduces the pressure and heats the adsorbent to desorb the adsorbed carbon dioxide, thereby recovering the carbon dioxide.

[0005] Heat pump-type heat source devices that use water as a heat medium cannot be started up as is if the temperature of the incoming chilled water is below a predetermined temperature (e.g., 9°C). For example, when the outside air temperature is low and the chilled water temperature in the pipes is low, the chilled water inlet temperature must be raised to a predetermined level or higher by using the exhaust heat of the pump itself that circulates the chilled water before starting up. Conventional technology leaves room for improvement in terms of shortening the start-up time when the outside air temperature is low.

[0006] The present invention aims to provide a carbon dioxide recovery device that performs a desorption process and an adsorption process by thermal control of a heat pump-type heat source, with a configuration that can be quickly started even when the outside air temperature is low. [Means for solving the problem]

[0007] (1) The present invention provides a module (for example, module 11 described later) that contains an adsorbent (for example, adsorbent 12 described later) and performs an adsorption process of sucking a gas containing carbon dioxide into the adsorbent to adsorb the carbon dioxide, and a desorption process of heating the adsorbent under reduced pressure around the adsorbent to desorb the carbon dioxide from the adsorbent; and a heat exchanger (for example, heat exchanger 70 described later) that has a heating heat medium line (for example, hot water line 112 described later) that supplies a heating heat medium (for example, hot water described later) to the module for heating, and a cooling heat medium line (for example, cold water line 111 described later) that supplies a cooling heat medium (for example, cold water described later) to the module for cooling, and the heat exchanger includes a heat pump type heat source (for example, heat source 81 described later) that heats the heating heat medium and cools the cooling heat medium, and a heat pump type heat source (for example, heat pump 82 described later) that heats the heating heat medium and cools the cooling heat medium. a heat-source high-temperature water circuit (for example, a heat-source high-temperature water circuit 85 described later) that circulates the heating heat medium between the heating heat medium tank and the heat source device; a cooling heat medium tank (for example, a cold water tank 82 described later) that stores the cooling heat medium cooled by the heat source device and a heat-source low-temperature water circuit (for example, a heat-source low-temperature water circuit 86 described later) that circulates the cooling heat medium between the cooling heat medium tank and the heat source device; a heating heat medium supply line (for example, hot water supply lines 96, 95a described later) that connects the heat-source high-temperature water circuit and the heat-source low-temperature water circuit; and a control device (for example, a control device 90 described later) that controls the supply of the heating heat medium from the heat-source high-temperature water circuit to the heat-source low-temperature water circuit (for example, a carbon dioxide recovery device 1 described later).

[0008] (2) In the carbon dioxide recovery device described in (1) above, the control device may perform control to supply the heating heat medium to the heat source low-temperature water circuit through the heating heat medium supply line when the inlet temperature of the cooling heat medium flowing into the heat source device does not exceed a start-up temperature set for the cooling heat medium.

[0009] (3) In the carbon dioxide recovery system described in (2) above, the heat exchanger further has a heat medium heating device (e.g., heater 150 described later) arranged in the heat source low-temperature water circuit, and the control device may perform control to start heating by the heat medium heating device when the inlet temperature of the heating heat medium flowing into the heat source device does not exceed a startable temperature set for the heating heat medium.

[0010] (4) In the carbon dioxide recovery device described in any one of (1) to (3) above, the heating heat medium supply line may have one end connected to the heating heat medium tank and the other end connected to a flow path (for example, a cold water side heat source supply line 121 described later) that sends the cooling heat medium from the cooling heat medium tank to the heat source device.

[0011] (5) In the carbon dioxide recovery device described in (3) above, one end of the heating heat medium supply line may be connected to the heating heat medium tank, and the other end may be connected to the upstream side of the heat medium heating device in a flow path (for example, a heater bypass line 124 described later) that sends the cooling heat medium from the cooling heat medium tank to the heat source device. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a carbon dioxide recovery device that performs the desorption process and the adsorption process by thermal control of a heat pump type heat source device, with a configuration that can be quickly started even when the outside air temperature is low. [Brief explanation of the drawings]

[0013] [Figure 1]FIG. 2 is a schematic diagram showing a configuration relating to gas flow in a carbon dioxide capture device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram showing a configuration relating to the flow of liquid in the carbon dioxide capture device of the present embodiment. [Figure 3] FIG. 2 is a schematic diagram showing the configuration of gas flow in the module of the carbon dioxide capture device of the present embodiment. [Figure 4] FIG. 2 is a schematic diagram showing the configuration regarding the flow of liquid in the module of the carbon dioxide capture device of the present embodiment. [Figure 5] 1 is a schematic diagram showing the configuration of a heat source circuit of a carbon dioxide recovery device according to an embodiment of the present invention. [Figure 6] FIG. 2 is a schematic diagram showing the connection positions of each line connected to the hot water tank. [Figure 7] FIG. 2 is a schematic diagram showing the connection positions of each line connected to the cold water tank. [Figure 8] 10 is a graph showing changes over time in the cold water inlet temperature and the hot water inlet temperature when the normal startup mode is selected. [Figure 9] 10 is a graph showing changes over time in the cold water inlet temperature and the hot water inlet temperature when the first low temperature mode is selected. [Figure 10] 10 is a graph showing changes over time in the cold water inlet temperature and the hot water inlet temperature when the second low temperature mode is selected. [Figure 11] 4 is a flowchart showing a process flow at the time of startup of the carbon dioxide capture device of the present embodiment. [Figure 12] FIG. 10 is a schematic diagram showing the configuration of a heat source circuit of a modified carbon dioxide recovery device. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0015] <Overall structure> Fig. 1 is a schematic diagram showing the configuration related to gas flow in a carbon dioxide capture device 1 according to one embodiment of the present invention. Fig. 2 is a schematic diagram showing the configuration related to liquid flow in the carbon dioxide capture device 1 of this embodiment. Note that the configuration related to liquid flow in the carbon dioxide capture device 1 is omitted in Fig. 1, and the configuration related to gas flow in the carbon dioxide capture device 1 is omitted in Fig. 2.

[0016] The carbon dioxide capture device 1 of this embodiment is applied to, for example, direct air capture (DAC) technology that captures carbon dioxide from the atmosphere in order to reduce the carbon dioxide concentration in the atmosphere. The carbon dioxide captured by the carbon dioxide capture device 1 is stored underground or reused as fuel or material.

[0017] As shown in Figures 1 and 2, the carbon dioxide capture device 1 of this embodiment includes a module unit 10, a fan 61, a vacuum pump 62, a carbon dioxide capture pump 63, an intercooler 64, a separator 65, a carbon dioxide tank 66, an inert gas tank 69, a heat exchange device 70, and a control device 90.

[0018] As shown in FIG. 1, the carbon dioxide recovery device 1 includes an adsorption line 101, a vacuum line 102, a carbon dioxide line 103, a circulation line 104, and an inert gas supply line 107 as gas flow paths.

[0019] The module unit 10 is configured by arranging a plurality of modules 11 in parallel that adsorb carbon dioxide. In this embodiment, a total of 16 modules 11 are arranged by a pair of left and right module units 10.

[0020] 3 is a schematic diagram showing the configuration related to the gas flow in module 11 of carbon dioxide capture device 1 of this embodiment. Module 11 is a carbon dioxide capture module including adsorbent 12, a first valve 21, a second valve 22, a third valve 23, a fourth valve 24, a pressure sensor 25, a carbon dioxide sensor 26, and a temperature sensor 27.

[0021] The adsorbent 12 is disposed inside the module 11 to adsorb carbon dioxide. The adsorbent 12 is a particulate material that has the property of adsorbing carbon dioxide at low temperatures (for example, in the range of -30°C to 50°C) and desorbing (releasing) carbon dioxide at high temperatures (for example, in the range of 50°C to 110°C) when the ambient carbon dioxide concentration is low. Examples of such adsorbent 12 include solid amine carbon dioxide adsorbents formed by supporting amines on porous materials such as silica.

[0022] The first valve 21 is an on-off valve arranged at the connection between the module 11 and a carbon dioxide line 103 that captures carbon dioxide. A carbon dioxide capture pump 63 is arranged in the carbon dioxide line 103. The second valve 22 is an on-off valve arranged at the connection between the module 11 and a vacuum line 102 in which a vacuum pump 62 is arranged. The third valve 23 is an on-off valve arranged at the inlet that takes in air and the like into the module 11. The fourth valve 24 is an on-off valve arranged at the connection between the adsorption line 101 and the module 11.

[0023] The first valve 21, the second valve 22, the third valve 23, and the fourth valve 24 are all controlled to open and close by a control device 90. The first valve 21, the second valve 22, the third valve 23, and the fourth valve 24 are each configured by, for example, a normally open butterfly valve.

[0024] The pressure sensor 25 measures the internal pressure of the module 11. The carbon dioxide sensor 26 measures the carbon dioxide concentration inside the module 11. The temperature sensor 27 measures the temperature of the adsorbent 12. Measurement information from the pressure sensor 25, the carbon dioxide sensor 26, and the temperature sensor 27 is sent to the control device 90.

[0025] Returning to FIG. 1 , the adsorption line 101 and the fan 61 will be described. The adsorption line 101 branches off and is connected to each of the modules 11. The fan 61 is located where the branched portions of the adsorption line 101 converge. When driven, the fan 61 generates a gas flow from "intake" to "exhaust" through the adsorption line 101 to the module 11. This supplies atmospheric air into the module 11. A carbon dioxide concentration sensor 611, a humidity sensor 612, and a temperature sensor 613 are located in the gas exhaust portion of the adsorption line 101, and measure the carbon dioxide, humidity, and temperature exhausted from the adsorption line 101. Measurement information from the carbon dioxide concentration sensor 611, the humidity sensor 612, and the temperature sensor 613 is sent to the control device 90.

[0026] The vacuum line 102 is branched and connected to each of the modules 11. The vacuum pump 62 is disposed at the point where the branched portions of the vacuum line 102 converge. When the vacuum pump 62 is driven, it sucks gas from inside the module 11 through the vacuum line 102, bringing the inside of the module 11 into a vacuum state or close to a vacuum state.

[0027] The carbon dioxide line 103 branches off and is connected to each of the modules 11. At the point where the branched portions of the carbon dioxide line 103 converge, a carbon dioxide capture pump 63, an intercooler 64, a separator 65, and a carbon dioxide tank 66 are arranged.

[0028] The carbon dioxide capture pump 63 applies suction force to send the carbon dioxide flowing through the carbon dioxide line 103 to the carbon dioxide tank 66. A one-way valve 631 is arranged upstream of the carbon dioxide capture pump 63 in the carbon dioxide line 103. This prevents gas from flowing back from the intercooler 64 side to the module 11 side.

[0029] The intercooler 64 is an intermediate cooling device that cools the high-temperature gas containing carbon dioxide recovered from the module 11 and separates it into gas and liquid.

[0030] The water separated into gas and liquid in intercooler 64 is recovered in separator 65. Separator 65 is provided with a first valve 651 and a second valve 652. First valve 651 opens and closes a path communicating with the gas phase part of separator 65. Second valve 652 opens and closes a path communicating with the liquid phase part of separator 65.

[0031] The carbon dioxide tank 66 stores the carbon dioxide recovered through the carbon dioxide line 103. A tank valve 661 is arranged on the carbon dioxide line 103 upstream of the carbon dioxide tank 66. The tank valve 661 is controlled to open and close by the control device 90. In addition, various sensors such as a pressure sensor 662, a flow rate sensor 663, a humidity sensor 664, a temperature sensor 665, and a carbon dioxide concentration sensor 666 are arranged on the carbon dioxide line 103 between the tank valve 661 and the carbon dioxide tank 66.

[0032] In addition to the carbon dioxide line 103, a circulation line 104 that returns ballast to the carbon dioxide capture pump 63 is connected to the carbon dioxide tank 66. A flow rate sensor 667 is disposed in the circulation line 104. In addition, the carbon dioxide tank 66 is provided with a pressure release valve 668 that releases pressure when the pressure reaches or exceeds a predetermined value.

[0033] Next, the inert gas tank 69 will be described. The inert gas tank 69 stores N2 as an inert gas supplied from an N2 gas cylinder 691 at a certain pressure or higher (for example, 980 kPa). A gas cylinder valve 692 is arranged between the inert gas tank 69 and the N2 gas cylinder 691. Also, the inert gas tank 69 is arranged with a pressure release valve 693 that releases the pressure when the pressure reaches a predetermined pressure or higher. A pressure sensor 694 is arranged inside the inert gas tank 69. Pressure information measured by the pressure sensor 694 is sent to the control device 90.

[0034] The inert gas tank 69 is connected to the carbon dioxide line 103 via an inert gas supply line 107. An inert gas valve 695 is disposed on the inert gas supply line 107. The inert gas valve 695 is controlled to open and close by the control device 90.

[0035] The heat exchanger 70 will be described with reference to Fig. 2. The heat exchanger 70 supplies thermal energy for heating the interior of each module 11 of the module unit 10 to a predetermined temperature when the module 11 performs the desorption step. The heat exchanger 70 also recovers unnecessary thermal energy when the module 11 performs the adsorption step.

[0036] The heat exchange device 70 of this embodiment includes a heat source circuit 80, a cold water line 111, a hot water line 112, a three-way valve 30, a bypass path 31, and a bypass valve 32.

[0037] The heat source circuit 80 mainly comprises a heat source device 81, a cold water tank 82, and a hot water tank 83, and performs heat exchange between a cooling heat medium flowing in a cold water line 111 and a heating heat medium flowing in a hot water line 112. Due to the heat transfer that occurs in the heat source circuit 80, the heat medium flowing in the cold water line 111 is cooled and the heat medium flowing in the hot water line 112 is heated. The heat medium is, for example, a liquid such as water. The detailed configuration of the heat source circuit 80 will be described later with reference to FIG. 5.

[0038] The chilled water line 111 is a pipe through which chilled water flows as a cooling heat medium. The chilled water line 111 is branched and connected to the upstream and downstream sides of each module 11, connecting the chilled water tank 82 to each module 11. Of the chilled water lines 111, the line connected to the upstream side of each module 11 is referred to as a chilled water supply line 111a, and the line connected to the downstream side of each module 11 is referred to as a chilled water return line 111b.

[0039] The chilled water supply line 111a is connected in parallel to multiple modules 11, allowing chilled water to be supplied in parallel to each module 11. A first chilled water circulation water pump 822 and a second chilled water circulation water pump 823 are arranged in the chilled water supply line 111a. The first chilled water circulation water pump 822 and the second chilled water circulation water pump 823 are, for example, cascade pumps.

[0040] Additionally, a circulation line 824 is arranged in the chilled water supply line 111a, returning from the downstream side of the second chilled water circulation water pump 823 to the upstream side. A safety valve 825 is arranged in this circulation line 824. The safety valve 825 relieves pressure when the pressure in the system between the second chilled water circulation water pump 823 and the chilled water line 111 exceeds a certain level, thereby suppressing a pressure increase. By arranging the safety valve 825, which relieves pressure in the event of an abnormality in the chilled water line 111, in parallel with the second chilled water circulation water pump 823, it is possible to achieve both a large flow rate circulation by the second chilled water circulation water pump 823 and safe operation.

[0041] The cold water recovery line 111b is also connected in parallel to the plurality of modules 11, and the recovery of the cold water after the cooling is completed can also be carried out in parallel for each module 11.

[0042] The hot water line 112 is a pipe through which hot water flows as a heat medium for heating. The hot water line 112 is branched and connected to the upstream and downstream sides of each module 11, connecting the hot water tank 83 to each module 11. Of the hot water lines 112, the line connected to the upstream side of each module 11 is referred to as a hot water supply line 112a, and the line connected to the downstream side of each module 11 is referred to as a hot water return line 112b.

[0043] The hot water supply line 112a is connected in parallel to the multiple modules 11, allowing hot water to be supplied to each module 11 in parallel. A first hot water circulation water pump 832 and a second hot water circulation water pump 833 are arranged on the hot water supply line 112a. The first hot water circulation water pump 832 and the second hot water circulation water pump 833 are, for example, cascade pumps. By using a cascade pump that generates a large amount of heat when driven, it is possible to further heat the heat medium passing through the first hot water circulation water pump 832 and the second hot water circulation water pump 833.

[0044] Additionally, a circulation line 834 is arranged in the hot water supply line 112a, returning from the downstream side of the second hot water circulation water pump 833 to the upstream side. A safety valve 835 is arranged in this circulation line 834. The safety valve 835 relieves pressure when the pressure in the system between the second hot water circulation water pump 833 and the hot water line 112 exceeds a certain level, thereby suppressing a pressure increase. By arranging the safety valve 835, which relieves pressure in the event of an abnormality in the hot water line 112, in parallel with the second hot water circulation water pump 833, it is possible to achieve both a high flow rate circulation by the second hot water circulation water pump 833 and safe operation.

[0045] The hot water return line 112b is also connected in parallel to the plurality of modules 11, and the recovery of hot water after heating can also be performed in parallel for each module 11.

[0046] The three-way valve 30 is connected to the cold water line 111, the hot water line 112, and the module 11. The three-way valve 30 is disposed on each of the upstream and downstream sides of the module 11. The three-way valve 30 is configured to be able to select, by flow path switching, a cold water connection state in which the cold water line 111 is connected to the module 11, a hot water connection state in which the hot water line 112 is connected to the module 11, and a cut-off state in which the cold water line 111 and the hot water line 112 are cut off from the module 11.

[0047] The flow path switching of the three-way valve 30 is controlled by the control device 90. The heat medium is introduced into the module 11 through the three-way valve 30 arranged on the upstream side, and the heat medium is returned to the heat source device 81 side through the three-way valve 30 arranged on the downstream side.

[0048] The bypass path 31 is a flow path that enables the movement of the heat medium between the modules 11. The bypass path 31 connects two modules 11. The modules 11 connected by the bypass path 31 may be adjacent modules, or may be non-adjacent modules 11 located at a distance.

[0049] The bypass valve 32 is disposed in the bypass path 31. The bypass valve 32 is disposed in each of the plurality of bypass paths 31. The bypass valve 32 is controlled to open and close by the control device 90.

[0050] 4 is a schematic diagram showing the configuration related to the flow of liquid in module 11 of the carbon dioxide capture device 1 of this embodiment. In the following description, the three-way valve 30 arranged upstream of module 11 will be referred to as three-way valve 30a, and the three-way valve 30 arranged downstream of module 11 will be referred to as three-way valve 30b.

[0051] 4, the module 11 includes an inlet-side flow path 33 connected to an inlet through which the heat medium flows in, and an outlet-side flow path 34 connected to an outlet through which the heat medium flows out. The bypass path 31 is connected to the outlet-side flow path 34 of the module 11 and is also connected to the inlet-side flow path 33 of another module 11.

[0052] A three-way valve 30a is disposed at the upstream end of the inlet flow path 33, and a three-way valve 30b is disposed at the downstream end of the outlet flow path 34. In the hot water connection state, the three-way valve 30a is connected to the hot water supply line 112a, and the three-way valve 30b is connected to the hot water return line 112b. In the cold water connection state, the three-way valve 30a is connected to the cold water supply line 111a, and the three-way valve 30b is connected to the cold water return line 111b.

[0053] The three-way valves 30a and 30b are configured to be able to adjust the flow rate. This flow rate adjustment function allows the flow rate of hot water to be adjusted when the hot water supply is connected, and the flow rate of cold water to be adjusted when the cold water supply is connected.

[0054] A temperature sensor 35 is disposed in the inlet-side flow path 33. A temperature sensor 36 and a flow rate sensor 37 are disposed in the outlet-side flow path 34. Measurement information from the temperature sensor 35, the temperature sensor 36, and the flow rate sensor 37 is transmitted to the control device 90.

[0055] Next, the control device 90 will be described. The control device 90 controls the operation of each part of the carbon dioxide capture device 1. The control device 90 controls the operation of devices used for adsorption and desorption of carbon dioxide, such as driving and stopping. The control device 90 selectively controls the timing of supplying a heat medium to each module 11 to heat or cool the modules 11, so that the multiple modules 11 repeatedly adsorb and desorb in time series.

[0056] The control device 90 controls the opening and closing of the first valve 21, second valve 22, third valve 23, and fourth valve 24 provided in each module 11, and the opening and closing of each bypass valve 32. The control device 90 also controls the drive of the fan 61, vacuum pump 62, carbon dioxide capture pump 63, first cold water circulation water pump 822, second cold water circulation water pump 823, first hot water circulation water pump 832, second hot water circulation water pump 833, etc., and controls the opening and closing of the safety valve 825 and safety valve 835.

[0057] The control device 90 is, for example, a computer having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc. The control device 90 may be configured as a single device or as a plurality of devices. The control device 90 may also be configured using an electric circuit such as a relay.

[0058] <Carbon dioxide capture> Next, we will explain the control for capturing carbon dioxide by the control device 90. The carbon dioxide capture device 1 alternately performs an adsorption process in which the adsorbent 12 in the module 11 adsorbs carbon dioxide in gases such as the air that has been taken in, and a desorption process in which the carbon dioxide adsorbed by the adsorbent 12 is desorbed, and stores the desorbed carbon dioxide in the carbon dioxide tank 66, thereby removing and capturing carbon dioxide from the air.

[0059] The adsorption process is a process in which carbon dioxide is adsorbed by the adsorbent 12 in the module 11. During the adsorption process, the third valve 23 and the fourth valve 24 of the module 11 are opened, and the first valve 21 and the second valve 22 are closed. In addition to controlling the opening and closing of the valves, the heat exchanger 70 controls the three-way valves 30a and 30b to a cold water connection state, allowing cold water to flow through the module 11 and cool the adsorbent 12 in the module 11. The fan 61 is driven, generating a gas flow from upstream to downstream, and gas containing carbon dioxide (e.g., atmospheric air) is drawn in through the third valve 23. The drawn gas passes through the adsorbent 12 in the module 11. At this time, the inside of the module 11 is cooled to room temperature (25°C) by the cold water, and the carbon dioxide in the gas is adsorbed by the adsorbent 12. Gases other than carbon dioxide, such as nitrogen and oxygen, are exhausted to the outside of the carbon dioxide capture device 1 through the fourth valve 24 and the adsorption line 101.

[0060] The desorption process is a process of desorbing carbon dioxide from the adsorbent 12 in the module 11. In the desorption process, the first valve 21, the third valve 23, and the fourth valve 24 of the module 11 are closed, and the second valve 22 is opened. The vacuum pump 62 is operated to draw air into the interior of the module 11 and reduce the pressure to create a vacuum or near-vacuum state. In addition to controlling the opening and closing of the valves, the heat exchanger 70 controls the three-way valves 30a and 30b to a hot water connection state, and hot water flows through the module 11 to supply thermal energy and raise the temperature of the adsorbent 12 in the module 11. By controlling the temperature rise of the adsorbent 12, the adsorbent 12 is also heated to a predetermined temperature (e.g., 80°C) sufficient for the desorption process, and the carbon dioxide adsorbed in the adsorbent 12 is desorbed. Next, the second valve 22, the third valve 23, and the fourth valve 24 are closed, the first valve 21 is opened, and the carbon dioxide recovery pump 63 is driven, and the carbon dioxide desorbed through the carbon dioxide line 103 is stored in the carbon dioxide tank 66. In this embodiment, each process is controlled so that 12 of the 16 modules 11 perform the adsorption process and the remaining four perform the desorption process.

[0061] <Heat source circuit> Next, the detailed configuration of the heat source circuit 80 will be described with reference to Fig. 5. Fig. 5 is a schematic diagram showing the configuration of the heat source circuit 80 of the carbon dioxide recovery device 1 of this embodiment.

[0062] As shown in Figure 5, the heat source circuit 80 of this embodiment includes a heat source device 81, a heat source high-temperature water circuit 85 including a hot water tank 83, a heat source low-temperature water circuit 86 including a cold water tank 82, a reservoir tank 88, and a hot water supply unit 95.

[0063] The heat source device 81 cools the heat medium introduced from the cold water tank 82 and heats the medium introduced from the hot water tank 83. The heat source device 81 is composed of a heat pump that transfers heat by utilizing the compression and expansion of gas.

[0064] The heat source high temperature water circuit 85 circulates hot water between the hot water tank 83 and the heat source device 81. The heat source high temperature water circuit 85 includes the hot water tank 83, a hot water side heat source supply line 221, and a hot water side heat source return line 222.

[0065] The hot water tank 83 is a heat storage device that has a heat insulating function and can store a heat medium. The capacity of the hot water tank 83 is preferably at least five times the maximum flow rate discharged by the hot water circulation water pump 831, which will be described later. By setting the capacity of the hot water tank 83 to be large relative to the flow rate of the heat medium, it is possible to suppress temperature fluctuations of the hot water (heat medium) during heat load fluctuations within a predetermined temperature range (for example, within ±5°C). In other words, the hot water tank 83 functions as a buffer for heat load fluctuations.

[0066] A temperature sensor 830 for measuring the temperature of the heat medium is disposed inside the hot water tank 83. The measurement result of the temperature sensor 830 is output to the control device 90. The hot water tank 83 is connected to the heat source device 81 via a hot water side heat source supply line 221 and a hot water side heat source return line 222.

[0067] The hot water side heat source supply line 221 is a path through which the heat medium flows from the hot water tank 83 to the heat source device 81. A valve 301, a hot water side circulation water pump 831, a flow rate sensor 231, and a temperature sensor 232 are arranged in this order from upstream to downstream on the hot water side heat source supply line 221. The hot water side circulation water pump 831 is configured, for example, by a centrifugal pump or the like, and circulates the heat medium between the hot water tank 83 and the heat source device 81. The flow rate sensor 231 measures the flow rate of the heat medium flowing into the heat source device 81 and outputs the measurement result to the control device 90. The temperature sensor 233 measures the temperature of the heat medium flowing into the heat source device 81 and outputs the measurement result to the control device 90.

[0068] The hot water side heat source return line 222 is a path through which the heat medium flows from the heat source device 81 to the hot water tank 83. A temperature sensor 233 and a valve 302 are arranged in this order from upstream to downstream on the hot water side heat source return line 222. The temperature sensor 233 measures the temperature of the hot water flowing out from the heat source device 81 and outputs the measurement result to the control device 90.

[0069] A hot water supply line 112a and a hot water return line 112b are connected to the hot water tank 83. A valve 305, a water filter 234, and a valve 306 are arranged on the hot water supply line 112a near the hot water tank 83. A valve 303 and a valve 304 are arranged on the hot water return line 112b near the hot water tank 83.

[0070] The connection positions (port positions) of each line of the hot water tank 83 are preferably set in consideration of the temperature stratification of the heat medium (hot water) stored in the hot water tank 83. Figure 6 is a schematic diagram showing the connection positions of each line connected to the hot water tank 83.

[0071] 6, temperature stratification occurs in the hot water stored in the hot water tank 83, with the temperature increasing toward the upper layer and decreasing toward the lower layer. The connection positions of the lines in the hot water tank 83 are set to be, in order from highest to lowest, the hot water side heat source return line 222, the hot water supply line 112a, the hot water side heat source supply line 221, and the hot water return line 112b.

[0072] The hot water side heat source return line 222 is a pipe that returns hot water (e.g., 82°C) heated by the heat source device 81, and returns the hot water to the highest temperature part in the temperature stratification. The hot water return line 112a is connected to the next highest position after the connection position of the hot water side heat source return line 222, so the hot water heated by the heat source device 81 is sent to the upstream side of the module 11 while maintaining a high temperature (e.g., 80°C) without significantly decreasing its temperature.

[0073] The hot water side heat source supply line 221 is a pipe for sending hot water to be heated to the heat source device 81, and is connected at the next highest position after the connection position of the hot water supply line 112a. This allows high-temperature hot water to be sent through the hot water supply line 112a, while hot water maintained at a relatively high temperature (for example, 75°C) by the hot water side heat source supply line 221 can be sent to the heat source device 81. The hot water return line 112b is a pipe for returning hot water at a relatively lowest temperature (for example, 72°C) after heating the module 11. Because the hot water return line 112b is connected at the lowest position, it is possible to reduce the amount of low-temperature hot water mixed into the hot water supply line 112a, which requires a high temperature.

[0074] In this embodiment, a hot water supply line 96 that supplies hot water from the heat-source high-temperature water circuit 85 to the heat-source low-temperature water circuit 86 is also connected to the upper part of the hot water tank 83. The connection position of the hot water supply line 96 is set, for example, at the same height as the connection positions of the hot water-side heat source return line 222 and the hot water supply line 112a. The configuration of the hot water supply line 96 will be described later.

[0075] Next, returning to Fig. 5, the heat-source low-temperature water circuit 86 will be described. The heat-source low-temperature water circuit 86 circulates cold water between the cold water tank 82 and the heat source device 81. The heat-source low-temperature water circuit 86 includes the cold water tank 82, a cold water-side heat source supply line 121, and a cold water-side heat source return line 122.

[0076] The cold water tank 82 is a heat storage device that has a heat insulating function and can store a heat medium. The capacity of the cold water tank 82 is preferably at least five times the maximum flow rate discharged by the cold water circulation water pump 821, which will be described later. By setting the capacity of the cold water tank 82 to be large relative to the flow rate of the heat medium, it is possible to suppress temperature fluctuations of the cold water (heat medium) during heat load fluctuations within a predetermined temperature range (for example, within ±5°C). In other words, the cold water tank 82 functions as a buffer for heat load fluctuations.

[0077] A temperature sensor 820 for measuring the temperature of the heat medium is disposed inside the cold water tank 82. The measurement result of the temperature sensor 820 is output to the control device 90. The cold water tank 82 is connected to the heat source device 81 via a cold water side heat source supply line 121 and a cold water side heat source return line 122.

[0078] Chilled water-side heat source supply line 121 is a path through which the heat medium flows from chilled water tank 82 to heat source device 81. A valve 307, a chilled water-side circulation water pump 821, a flow rate sensor 131, and a temperature sensor 132 are arranged in chilled water-side heat source supply line 121. Chilled water-side circulation water pump 821 is configured, for example, by a centrifugal pump or the like, and circulates the heat medium between chilled water tank 82 and heat source device 81. Flow rate sensor 131 measures the flow rate of the heat medium flowing into heat source device 81 and outputs the measurement result to control device 90. Temperature sensor 132 measures the temperature of the heat medium flowing into heat source device 81 and outputs the measurement result to control device 90.

[0079] A radiator bypass line 123 for cooling the heat medium and a heater bypass line 124 for heating the heat medium are connected to the cold water side heat source supply line 121. The radiator bypass line 123 and the heater bypass line 124 are temperature adjustment circuits that adjust the temperature of the heat medium flowing into the heat source device 81 to an operable temperature when the outside air temperature or heat load fluctuates.

[0080] The radiator bypass line 123 is connected between the chilled water-side circulation water pump 821 and the flow rate sensor 131 in the chilled water-side heat source supply line 121. A valve 141 and a radiator fan 142 are arranged in the radiator bypass line 123. The valve 141 can open and close the flow path and adjust the flow rate based on control signals from the control device 90. The radiator fan 142 is a heat dissipation device that cools the heat medium passing through the radiator bypass line 123. The cooling of the heat medium by the radiator bypass line 123 is performed mainly during high temperatures such as in summer. By cooling the heat medium by the radiator bypass line 123, the temperature of the chilled water introduced into the heat source device 81 is controlled to be equal to or lower than a preset threshold value.

[0081] The heater bypass line 124 is located in the cold water-side heat source supply line 121 between the cold water-side circulation water pump 821 and the flow rate sensor 131, and is connected to the inside of the radiator bypass line 123. A valve 308 and a heater 150 are arranged in the heater bypass line 124. The heater 150 is driven by a control signal or a relay drive signal from the control device 90, and heats the heat medium flowing through the heater bypass line 124. The heating of the heat medium by the heater bypass line 124 is performed mainly when the temperature is low, such as during start-up in winter. By heating the heat medium by the heater bypass line 124, the temperature of the heat medium introduced into the heat source device 81 is controlled to be equal to or higher than a preset threshold value.

[0082] The chilled water side heat source return line 122 is a path through which the heat medium flows from the heat source device 81 to the chilled water tank 82. A temperature sensor 133, valves 309, 310, 311, and 312 are arranged in this order from upstream to downstream on the chilled water side heat source return line 122. The temperature sensor 132 measures the temperature of the chilled water flowing out from the heat source device 81 and outputs the measurement result to the control device 90.

[0083] A chilled water supply line 111a and a chilled water return line 111b are connected to the chilled water tank 82. A valve 315, a water filter 134, and a valve 316 are arranged on the chilled water supply line 111a near the chilled water tank 82. A valve 313 and a valve 314 are arranged on the chilled water return line 111b near the chilled water tank 82.

[0084] The connection positions (port positions) of each line of the chilled water tank 82 are preferably set in consideration of the temperature stratification of the heat medium (chilled water) stored in the chilled water tank 82. Figure 7 is a schematic diagram showing the connection positions of each line connected to the chilled water tank 82.

[0085] 7, the chilled water stored in the chilled water tank 82 is thermally stratified, with the temperature increasing toward the upper layer and decreasing toward the lower layer. The connection positions of the lines in the chilled water tank 82 are set to be, in order from highest to lowest, the chilled water return line 111b, the chilled water side heat source return line 122, the chilled water supply line 111a, and the chilled water side heat source supply line 121.

[0086] The chilled water return line 111b is a pipe that returns chilled water at a relatively highest temperature (e.g., 36°C) after cooling the module 11. Because the chilled water return line 111b is connected at the highest position, it is possible to prevent high-temperature chilled water from mixing with the chilled water sent out from the chilled water supply line 111a. The chilled water side heat source return line 122 is a pipe that returns chilled water (e.g., 30°C) cooled by the heat source device 81, and is connected at the next highest position after the connection position of the chilled water return line 111b. The chilled water that returns through the chilled water side heat source return line 122 moves to the lower side of the temperature stratification.

[0087] The chilled water supply line 111a is connected to the next highest position after the connection position of the chilled water side heat source return line 122, and therefore sends out the chilled water cooled in the heat source device 81 to the upstream side of the module 11 while maintaining a low temperature (for example, 31°C) without significantly increasing the temperature. The chilled water side heat source supply line 121 is connected to the lowest position, and sends out to the heat source device 81 chilled water at a low temperature (for example, 33°C) that was not sent from the chilled water supply line 111a to the module 11.

[0088] Next, returning to FIG. 5, the equipment heat recovery circuit 87 that cools the target equipment such as the intercooler 64, the vacuum pump 62, and the carbon dioxide recovery pump 63 included in the heat source low-temperature water circuit 86 and increases the temperature of the heat medium will be described.

[0089] The equipment heat recovery circuit 87 is connected in parallel to the heat-source low-temperature water circuit 86. The equipment heat recovery circuit 87 of this embodiment includes a first equipment heat cooling line 126 that exchanges heat with the intercooler 64, and a second equipment heat cooling line 127 that exchanges heat with the vacuum pump 62 and the carbon dioxide recovery pump 63.

[0090] The first equipment thermal cooling line 126 has its upstream end connected to the chilled water side heat source return line 122 and its downstream end connected to the chilled water side heat source supply line 121. In this embodiment, the connection point of the upstream end of the first equipment thermal cooling line 126 is between valves 309 and 310 on the chilled water side heat source return line 122. The connection point of the lower end of the first equipment thermal cooling line 126 is between valve 307 on the chilled water side heat source supply line 121 and chilled water side circulation water pump 821.

[0091] The first equipment heat cooling line 126 is connected to the intercooler 64 that generates steam condensation heat, and cools the intercooler 64 with cold water to recover the steam condensation heat as waste heat. The cold water is heated by heat exchange with the intercooler 64 and then sent to the cold water side heat source supply line 121.

[0092] A flow rate sensor 841 and a temperature sensor 842 are arranged upstream of the intercooler 64 on the first equipment thermal cooling line 126, and a temperature sensor 843 and a valve 317 are arranged downstream of the intercooler 64. The flow rate sensor 841 measures the flow rate of the heat medium before heat exchange with the intercooler 64 and outputs the measurement result to the control device 90. The temperature sensor 842 measures the temperature of the heat medium before heat exchange with the intercooler 64 and outputs the measurement result to the control device 90. The temperature sensor 843 measures the temperature of the heat medium after heat exchange with the intercooler 64 and outputs the measurement result to the control device 90.

[0093] The second equipment thermal cooling line 127 has its upstream end connected to the chilled water side heat source return line 122 and its downstream end connected to the chilled water side heat source supply line 121. In this embodiment, the connection point of the upstream end of the second equipment thermal cooling line 127 is between the valves 310 and 311 on the chilled water side heat source return line 122. The connection point of the lower end of the second equipment thermal cooling line 127 is between the valve 307 on the chilled water side heat source supply line 121 and the chilled water side circulation water pump 821, which is upstream of the connection point of the downstream end of the first equipment thermal cooling line 126.

[0094] Moreover, the second equipment thermal cooling line 127 of this embodiment includes a first branch line 127a for cooling the vacuum pump 62 and a second branch line 127b for cooling the carbon dioxide capture pump 63.

[0095] The first branch line 127a is connected to the vacuum pump 62 and uses cold water to cool the vacuum pump 62. The heat medium is heated by heat exchange with the vacuum pump 62 and then merges with the second branch line 127b, and is sent to the cold water side heat source supply line 121.

[0096] A flow rate sensor 851 and a temperature sensor 852 are arranged upstream of the vacuum pump 62 on the first branch line 127a, and a temperature sensor 853 is arranged downstream of the vacuum pump 62. The flow rate sensor 851 measures the flow rate of the heat medium before heat exchange with the vacuum pump 62 and outputs the measurement result to the control device 90. The temperature sensor 852 measures the temperature of the heat medium before heat exchange with the vacuum pump 62 and outputs the measurement result to the control device 90. The temperature sensor 853 measures the temperature of the chilled water after heat exchange with the vacuum pump 62 and outputs the measurement result to the control device 90.

[0097] The second branch line 127b is connected to the carbon dioxide capture pump 63 and uses a heat medium to cool the carbon dioxide capture pump 63. The heat medium is heated by heat exchange with the carbon dioxide capture pump 63 and then merges with the first branch line 127a, and is sent to the chilled water side heat source supply line 121.

[0098] A flow rate sensor 861 and a temperature sensor 862 are arranged on the second branch line 127b upstream of the carbon dioxide capture pump 63, and a temperature sensor 863 is arranged downstream of the carbon dioxide capture pump 63. The flow rate sensor 861 measures the flow rate of the heat medium before heat exchange with the carbon dioxide capture pump 63 and outputs the measurement result to the control device 90. The temperature sensor 862 measures the temperature of the heat medium before heat exchange with the carbon dioxide capture pump 63 and outputs the measurement result to the control device 90. The temperature sensor 863 measures the temperature of the heat medium after heat exchange with the carbon dioxide capture pump 63 and outputs the measurement result to the control device 90.

[0099] An equipment cooling pump 870 is disposed upstream of the branch point of the first branch line 127a and the second branch line 127b in the second equipment thermal cooling line 127. In addition, a valve 318 and a valve 319 are disposed downstream of the junction of the first branch line 127a and the second branch line 127b in the second equipment thermal cooling line 127.

[0100] The equipment cooling pump 870 of this embodiment is configured by a cascade pump having a sufficient head to pump the heat medium without being hindered by the high pressure loss of the vacuum pump 62 and the carbon dioxide capture pump 63, which are the equipment for which heat recovery is performed. The heat generated by driving the equipment cooling pump 870 is also recovered as exhaust heat by the cold water.

[0101] As described above, the equipment heat recovery circuit 87 recovers the heat of steam condensation from the intercooler 64 and the exhaust heat from the vacuum pump 62 and the carbon dioxide recovery pump 63 into a heat medium to cool the target equipment, and the heat recovery makes it possible to flow the heat medium into the heat source device 81 at a high temperature potential.

[0102] The equipment heat recovery circuit 87 uses the low-temperature heat medium cooled by the heat source device 81 to cool the target equipment, which are the vacuum pump 62, the carbon dioxide capture pump 63, and the intercooler 64. After cooling the target equipment (vacuum pump 62, carbon dioxide capture pump 63, and intercooler 64) and recovering the exhaust heat, the chilled water merges with the chilled water-side heat source supply line 121 through which chilled water discharged from the chilled water tank 82 (for example, a high-temperature location in the upper layer of the chilled water tank 82) flows, and is introduced into the heat source device 81. The chilled water after recovering the exhaust heat is heated to an appropriate temperature range.

[0103] In this embodiment, the cold water is further adjusted to an appropriate temperature range before entering the heat source device 81 by the radiator bypass line 123 for cooling the cold water or the heater bypass line 124 for heating the cold water, so that even in operations with large fluctuations in the heat load, it is possible to smooth out the heat fluctuations over time and keep the inflow temperature to the heat source device 81 constant.

[0104] Next, the configuration of the reservoir tank 88 will be described. The reservoir tank 88 is a tank capable of storing a heat medium. The reservoir tank 88 is connected to the hot water tank 83 and the cold water tank 82. A valve 320 is disposed between the reservoir tank 88 and the hot water tank 83, and another valve 321 is disposed between the reservoir tank 88 and the cold water tank 82. When the amount of heat medium stored in the hot water tank 83 needs to be adjusted, the valve 320 is opened, and the heat medium is transferred between the reservoir tank 88 and the hot water tank 83. Similarly, when the amount of heat medium stored in the cold water tank 82 needs to be adjusted, the valve 321 is opened, and the heat medium is transferred between the reservoir tank 88 and the cold water tank 82. A level sensor 880 for determining the amount of heat medium stored is disposed inside the reservoir tank 88. The measurement result of the level sensor 880 is output to the control device 90. The control device 90 uses the measurement result of the level sensor 880 to determine whether the reservoir tank 88 is usable or not.

[0105] Next, a description will be given of the hot water supply unit 95. The hot water supply unit 95 includes a hot water supply line 96 that connects the heat-source high-temperature water circuit 85 and the heat-source low-temperature water circuit 86, and a valve 97 arranged on the hot water supply line 96.

[0106] In this embodiment, the hot water supply line 96 has its upstream end connected to the hot water tank 83 and its downstream end connected upstream of the flow sensor 131 in the cold water side heat source supply line 121 of the heat source low temperature water circuit 86.

[0107] The valve 97 is controlled based on a control signal from the control device 90. The valve 97 is normally controlled to a closed state and is controlled to an open state as necessary. When the valve 97 is controlled to an open state, hot water is supplied to the heat-source low-temperature water circuit 86 through the hot water supply line 96. The valve 97 in this embodiment is configured so that its opening degree can be changed, and it is also possible to adjust the amount of hot water flowing from the heat-source high-temperature water circuit 85 to the heat-source low-temperature water circuit 86.

[0108] <Heat supply control> Next, we will explain the hot water supply control that is performed when the control device 90 is started up. In the following explanation, the temperature of the cold water flowing into the heat source device 81 detected by the temperature sensor 132 will be referred to as the cold water inlet temperature, and the temperature of the hot water flowing into the heat source device 81 detected by the temperature sensor 232 will be referred to as the hot water inlet temperature.

[0109] In this embodiment, the control device 90 has three modes for starting the heat source device 81: a normal start-up mode, a first low-temperature start-up mode, and a second low-temperature start-up mode.

[0110] The normal startup mode will be described with reference to Figure 8. Figure 8 is a graph showing the changes over time in the chilled water inlet temperature and the hot water inlet temperature when the normal startup mode is selected. As shown in Figure 8, a startup temperature is set in advance for the chilled water inlet temperature as the limit temperature at which heat source device 81 is started. This graph shows that, although the chilled water inlet temperature and the hot water inlet temperature gradually decrease over time during a period when the average outside air temperature is higher than the startup temperature, both the chilled water inlet temperature and the hot water inlet temperature always exceed the startup temperature.

[0111] If the chilled water inlet temperature is above the startup temperature, the chilled water flowing into the heat source unit 81 satisfies the temperature conditions for proper startup, and there is no need to supply hot water from the hot water tank 83 to the heat-source low-temperature water circuit 86. Therefore, the control device 90 controls the valve 97 to the closed state, and starts startup operation in normal startup mode, which stops the supply of hot water from the hot water tank 83 through the hot water supply line 96. This state is the same as the circuit in normal operation after startup operation.

[0112] The first low temperature mode will be described with reference to Fig. 9. Fig. 9 is a graph showing the changes over time in the chilled water inlet temperature and the hot water inlet temperature when the first low temperature mode is selected. The graph shown in Fig. 9 shows that when the average outside air temperature is lower than the start-up temperature, the chilled water inlet temperature and the hot water inlet temperature gradually decrease over time, and eventually the hot water inlet temperature exceeds the start-up temperature, but the chilled water inlet temperature falls below the start-up temperature.

[0113] If the chilled water inlet temperature is below the startup temperature, the chilled water flowing into the heat source device 81 does not satisfy the temperature conditions for proper startup, and hot water must be supplied from the hot water tank 83 to the heat source low-temperature water circuit 86. Therefore, the control device 90 controls the valve 97 to an open state, and executes the first low-temperature mode, which starts the supply of hot water from the hot water tank 83 through the hot water supply line 96. In the first low-temperature mode, only the heat pump, which consumes less energy, is started, and the energy consumption required to heat the chilled water can be reduced.

[0114] The second low temperature mode will be described with reference to Fig. 10. Fig. 10 is a graph showing the changes over time in the chilled water inlet temperature and the hot water inlet temperature when the second low temperature mode is selected. The graph shown in Fig. 10 shows that the chilled water inlet temperature and the hot water inlet temperature gradually decrease over time during a period when the average outside air temperature is even lower than in the example of the graph in Fig. 9, and that both the chilled water inlet temperature and the hot water inlet temperature eventually fall below the start-up temperature.

[0115] If both the chilled water inlet temperature and the hot water inlet temperature are below the startup temperature, the chilled water flowing into the heat source device 81 does not meet the temperature conditions for proper startup. In the example of the graph in FIG. 10, the chilled water needs to be heated even more than in the example of the graph in FIG. 9. Therefore, the control device 90 controls the valve 97 to an open state, starts supplying hot water from the hot water tank 83 through the hot water supply line 96, and executes the second low-temperature mode, which also activates the heater 150. This allows the chilled water to be heated reliably and quickly using two types of heating means: mixing hot water and heating by the heater 150. When the inlet chilled water temperature exceeds the startup temperature, the heater 150 is stopped, and only the heat source device 81 is operated, thereby reducing energy consumption. Note that the hot water gradually rises in temperature as the second low-temperature mode is executed due to the exhaust heat recovery of the hot water circulation water pump 831, and the temperature exceeds the startup temperature.

[0116] In this way, by connecting the hot water tank 83 to the heat source low-temperature water circuit 86 and starting the heater 150 depending on the temperature potential of the cold water supplied from the cold water tank 82 at startup, appropriate startup control can be achieved according to the external environment, such as the outside air temperature.

[0117] The control device 90 can also adjust the water volumes of the heat-source high-temperature water circuit 85 and the heat-source low-temperature water circuit 86 via the reservoir tank 88 to prevent the heat-source low-temperature water circuit 86 from overflowing due to the amount of hot water transferred from the heat-source high-temperature water circuit 85 to the heat-source low-temperature water circuit 86. The reservoir tank 88 can absorb the transfer of water volume between the cold and hot water, thereby improving the reliability of the system. In this configuration, it is preferable that the control device 90 adjusts the flow rate to transfer an appropriate amount of hot heat to the heat-source low-temperature water circuit 86, and also adjusts the capacity of the hot water tank 83 and the water level of the return water from the reservoir tank 88. This makes it possible to respond to heat fluctuations caused by changes in the external environment, etc., and realizes a configuration of the carbon dioxide capture device 1 that is more energy efficient.

[0118] Next, the startup control of the carbon dioxide capture device 1 by the control device 90 will be described with reference to Fig. 11. Fig. 11 is a flowchart showing the flow of processing at the startup of the carbon dioxide capture device 1 of this embodiment.

[0119] In step S11, the control device 90 starts acquiring the cold water inlet temperature from the temperature sensor 132 and starts acquiring the hot water inlet temperature from the temperature sensor 232. That is, the control device 90 starts monitoring the cold water inlet temperature and the hot water inlet temperature.

[0120] In step S12, the control device 90 determines whether the acquired chilled water inlet temperature is higher than a preset start-up temperature. If the chilled water inlet temperature is higher than the start-up temperature, the control device 90 proceeds to step S13 (step S12; Yes).

[0121] In step S13, the control device 90 sets the normal startup mode and starts the warm-up operation of the heat source device 81. In step S14, the control device 90 ends the startup operation and ends the process.

[0122] In step S12, if the chilled water inlet temperature does not exceed the start-up temperature, the control device 90 advances the process to step S15 (step S12; No).

[0123] In step S15, the control device 90 determines whether the acquired hot water inlet temperature is higher than a preset start-up temperature. If the hot water inlet temperature is higher than the start-up temperature, the control device 90 proceeds to step S16 (step S15; Yes), and if the hot water inlet temperature is not higher than the start-up temperature, the control device 90 proceeds to step S17 (step S15; No).

[0124] In step S16, the control device 90 sets the first low-temperature start-up mode because the hot water inlet temperature is above the possible start-up temperature but the cold water inlet temperature is below the possible start-up temperature. In the first low-temperature start-up mode, the control device 90 warms up the heat source device 81 and controls the valve 97 to an open state, starting the supply of hot water from the hot water tank 83 to the heat-source low-temperature water circuit 86. After processing step S16, the control device 90 returns the process to step S12.

[0125] In step S17, the control device 90 sets the second low-temperature start-up mode because both the cold water inlet temperature and the hot water inlet temperature are below the start-up temperature. In the second low-temperature start-up mode, the control device 90 controls the valve 97 to an open state and starts the heater 150 in parallel with the warm-up operation of the heat source device 81. This starts the supply of hot water from the hot water tank 83 to the heat-source low-temperature water circuit 86, and starts heating of cold water by the heater 150. After processing step S17, the control device 90 returns the processing to step S12.

[0126] Whether the first or second low-temperature start mode is selected, the processing from step S15 onwards loops until the chilled water inlet temperature exceeds the possible start temperature in step S12. If the chilled water inlet temperature is below the possible start temperature but the hot water inlet temperature exceeds the possible start temperature while the second low-temperature start mode is set, the control device 90 changes the control mode from the second low-temperature start mode to the first low-temperature start mode. Also, even if either the first or second low-temperature start mode is set, the control device 90 will change the control mode to the normal start mode if the chilled water inlet temperature exceeds the possible start temperature.

[0127] As described above, the carbon dioxide capture device 1 of this embodiment includes a plurality of modules 11 each having an adsorbent 12 therein, and performing an adsorption step of sucking a gas containing carbon dioxide into the adsorbent 12 to adsorb the carbon dioxide, and a desorption step of heating the adsorbent 12 in a state where the atmosphere around the adsorbent 12 is reduced in pressure to desorb carbon dioxide from the adsorbent 12, and a heat exchanger 70 having a hot water line (heating heat medium line) 112 for supplying hot water (heating heat medium) to each of the modules 11 for heating, and a cold water line (cooling heat medium line) 111 for supplying cold water (cooling heat medium) to each of the modules 11 for cooling. The heat exchanger 70 heats the hot water. the heat source 81 includes a heat pump type heat source device 81 that heats and cools cold water, a hot water tank (heating heat medium tank) 83 that stores hot water heated by the heat source device 81 and circulates hot water between the hot water tank 83 and the heat source device 81, a heat source low temperature water circuit 86 that includes a cold water tank (cooling heat medium tank) 82 that stores cold water cooled by the heat source device 81 and circulates cold water between the cold water tank 82 and the heat source device 81, a hot water supply line (heating heat medium supply line) 96 that connects the heat source high temperature water circuit 85 and the heat source low temperature water circuit 86, and a control device 90 that controls the supply of hot water from the heat source high temperature water circuit 85 to the heat source low temperature water circuit 86.

[0128] As a result, even when the outside air temperature is low and the temperature of the chilled water is low, making it impossible to start normal operation of the heat source device 81, hot water can be supplied from the heat-source high-temperature water circuit 85 to the heat-source low-temperature water circuit 86 under the control of the control device 90. The hot water supplied from the heat-source high-temperature water circuit 85 to the heat-source low-temperature water circuit 86 is mixed with the chilled water, thereby raising the temperature of the chilled water flowing into the heat source device 81. This shortens the time until normal operation of the heat source device 81 begins, reduces the energy consumption required for startup, and enables efficient operation of the carbon dioxide recovery device 1.

[0129] In addition, the control device 90 of this embodiment controls the supply of hot water to the heat source low-temperature water circuit 86 through the hot water supply line 96 when the inlet temperature of the cold water flowing into the heat source device 81 does not exceed the start-up temperature set for the cold water.

[0130] This allows hot water to be supplied to the heat source low temperature water circuit 86 when the cold water inlet temperature does not reach the minimum temperature required for proper start-up of the heat source device 81, thereby avoiding unnecessary supply of hot water from the heat source high temperature water circuit 85 to the heat source low temperature water circuit 86.

[0131] In addition, the heat exchange device 70 of this embodiment further has a heater (heat medium heating device) 150 arranged in the heat source low-temperature water circuit 86, and the control device 90 controls the heater 150 to start heating when the inlet temperature of the hot water flowing into the heat source device 81 does not exceed the start-up temperature set for the hot water.

[0132] As a result, even when the outside air temperature is low and the hot water inlet temperature does not reach the minimum temperature required for proper start-up of the heat source device 81, heating is performed by the heater 150, so the cold water can be quickly raised to a temperature at which start-up is possible.

[0133] In addition, in this embodiment, the hot water supply line 96 has one end connected to the hot water tank 83 and the other end connected to the cold water side heat source supply line 121, which serves as a flow path for transporting cold water from the cold water tank 82 to the heat source device 81.

[0134] This allows hot water stored at a high temperature in the hot water tank 83 to be supplied directly to the heat-source low-temperature water circuit 86 via the hot water supply line 96, and the temperature of the cold water flowing into the heat source device 81 can be raised more efficiently. A simple piping configuration in which the hot water supply line 96 is connected can realize a configuration in which the temperature of cold water can be raised at low cost.

[0135] Next, a modified example in which a hot water supply line 96a different from the hot water supply line 96 of the above embodiment is used will be described with reference to Fig. 12. Fig. 12 is a schematic diagram showing the configuration of a heat source circuit 80 of a modified carbon dioxide recovery device 1. Note that components common to or similar to those of the above embodiment are given the same reference numerals, and detailed description thereof will be omitted.

[0136] 12, in the modified example, the configuration of the hot water supply line 96a is different from the configuration of the hot water supply line 96a in the above embodiment. One end of the hot water supply line 96a in the modified example is connected to the hot water tank 83, and the other end is connected to the upstream side of the heater 150 in the heater bypass line 124, which serves as a flow path for sending cold water from the cold water tank 82 to the heat source device 81.

[0137] This allows hot water stored at a high temperature in the hot water tank 83 to be supplied directly to the heat-source low-temperature water circuit 86 via the hot water supply line 96a, and the hot water supplied via the hot water supply line 96a can be heated by the heater 150. Therefore, the temperature of the cold water flowing into the heat source device 81 can be raised quickly, effectively shortening the time required to start operating the carbon dioxide recovery device 1.

[0138] Furthermore, the hot water supply line may be connected to a position different from that of the above-described embodiment and modified examples. For example, the hot water supply line may be configured so that its upstream end is connected to the hot water tank 83 and its downstream end is connected to the upstream side of the cold water circulation water pump 821. With this configuration, exhaust heat generated by the operation of the cold water circulation water pump 821 can be utilized, enabling more rapid warm-up operation.

[0139] Furthermore, in the above embodiment, the control device 90 determines whether to supply water from the heat-source high-temperature water circuit 85 to the heat-source low-temperature water circuit 86 using the detected values ​​of the temperature sensor 132 and the temperature sensor 232, but this configuration is not limitative. For example, it is also possible to predict temperature transitions based on the outside air temperature and the stoppage time of the carbon dioxide capture device 1, and to determine an operation pattern based on the temperature transitions. In this case, the number of temperature sensors required can be reduced, leading to cost savings.

[0140] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and modifications. Furthermore, the effects described in the above embodiments are merely preferred effects, and the present invention is not limited to those described in the above embodiments. [Explanation of symbols]

[0141] 1. Carbon dioxide capture device 11 Modules 12 Adsorbent 62 Vacuum pump 63 Carbon dioxide capture pump 64 Intercooler 70 Heat exchange equipment 80 Heat source circuit 81 Heat source device 82 Cold water tank (cooling heat medium tank) 83 Hot water tank (heating medium tank) 85 Heat source high temperature water circuit 86 Heat source low temperature water circuit 87 Equipment heat recovery circuit 90 Control device 96, 96a Hot water supply line (heating medium supply line) 111 Chilled water line (cooling heat medium line) 111a Chilled water line (cooling heat medium line) 111b Cold water return line (cooling heat medium return line) 112 Hot water line (heating medium line) 112a Hot water line (heating medium line) 112b Hot water return line (heating medium return line) 150 Heater (heat medium heating device)

Claims

1. a module having an adsorbent therein, which performs an adsorption step of drawing a gas containing carbon dioxide into the adsorbent to adsorb the carbon dioxide, and a desorption step of heating the adsorbent under a reduced pressure around the adsorbent to desorb the carbon dioxide from the adsorbent; a heat exchange device having a heating heat medium line for supplying a heating heat medium to the module for heating and a cooling heat medium line for supplying a cooling heat medium to the module for cooling; Equipped with The heat exchange device is a heat pump type heat source device that heats the heating heat medium and cools the cooling heat medium; a heat source high-temperature water circuit including a heating heat medium tank that stores the heating heat medium heated by the heat source device, and circulating the heating heat medium between the heating heat medium tank and the heat source device; a heat source low-temperature water circuit including a cooling heat medium tank that stores the cooling heat medium cooled by the heat source device, and circulating the cooling heat medium between the cooling heat medium tank and the heat source device; a heating medium supply line connecting the heat source high-temperature water circuit and the heat source low-temperature water circuit; a control device that controls the supply of the heating medium from the heat-source high-temperature water circuit to the heat-source low-temperature water circuit; having Carbon dioxide capture equipment.

2. The control device When the inlet temperature of the cooling heat medium flowing into the heat source device does not exceed a start-up temperature set for the cooling heat medium, control is performed to supply the heating heat medium to the heat-source low-temperature water circuit through the heating heat medium supply line. The carbon dioxide capture device according to claim 1 .

3. The heat exchange device is The system further includes a heat medium heating device disposed in the heat source low-temperature water circuit, The control device When the inlet temperature of the heating medium flowing into the heat source device does not exceed a startable temperature set for the heating medium, control is performed to start heating by the heat medium heating device. The carbon dioxide capture device according to claim 2 .

4. The heating medium supply line One end of the cooling system is connected to the heating medium tank, and the other end of the cooling system is connected to a flow path that sends the cooling medium from the cooling medium tank to the heat source device. The carbon dioxide recovery device according to any one of claims 1 to 3.

5. The heating medium supply line One end of the cooling medium tank is connected to the heating medium tank, and the other end of the cooling medium tank is connected to the upstream side of the heat medium heating device in a flow path that sends the cooling medium from the cooling medium tank to the heat source device. The carbon dioxide capture device according to claim 3 .

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