Carbon dioxide recovery system

Abstract

This carbon dioxide recovery system is provided with a supply path, a carbon dioxide adsorption unit having a treatment region and a regeneration region, a discharge path, a regeneration path, a circulation path, and a carbon dioxide separator. The supply path guides air. The treatment region causes an adsorbent to adsorb carbon dioxide contained in the air. The regeneration region regenerates the adsorbent using a regeneration fluid. The discharge path guides the air in which the concentration of carbon dioxide is reduced through the treatment region. The regeneration path guides the regeneration fluid to the regeneration region. The circulation path guides a regeneration discharge fluid discharged by regenerating the adsorbent by means of the regeneration fluid. The carbon dioxide separator obtains the regeneration fluid by separating at least a portion of the carbon dioxide from the regeneration discharge fluid.

Description

Technical Field

[0001] The present disclosure relates to carbon dioxide recovery systems. Background Art

[0002] Patent Document 1 discloses a DAC (Direct Air Capture) technology for collecting carbon dioxide from the air.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2021-169079 Summary of the invention

[0006] Problems to be solved by the invention

[0007] In the above-mentioned technology, the recovery efficiency of carbon dioxide may be reduced.

[0008] In view of the above situation, an object of the present disclosure is to provide a carbon dioxide recovery system capable of improving the recovery efficiency of carbon dioxide.

[0009] Means for solving problems

[0010] One embodiment of the carbon dioxide recovery system disclosed herein is a carbon dioxide recovery system, wherein the carbon dioxide recovery system comprises: a supply path, which guides air; a carbon dioxide adsorption unit, which has a processing area for causing an adsorbent to adsorb carbon dioxide contained in the air and a regeneration area for regenerating the adsorbent using a regeneration fluid; an outlet path, which guides the air that has passed through the processing area to reduce the concentration of carbon dioxide; a regeneration path, which guides the regeneration fluid to the regeneration area; a circulation path, which guides the regeneration exhaust fluid discharged by regenerating the adsorbent using the regeneration fluid; and a carbon dioxide separator, which obtains the regeneration fluid by separating at least a portion of the carbon dioxide from the regeneration exhaust fluid.

[0011] Effects of the Invention

[0012] According to the present disclosure, a carbon dioxide recovery system capable of improving the recovery efficiency of carbon dioxide can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the carbon dioxide recovery system of embodiment 1.

[0014] Figure 2 This is a schematic diagram of a portion of a carbon dioxide recovery system of Embodiment 2.

[0015] Figure 3 This is a schematic diagram of a portion of a carbon dioxide recovery system of embodiment 3.

[0016] Figure 4 This is a schematic diagram of a carbon dioxide recovery system in Embodiment 4.

[0017] Figure 5 This is a schematic diagram of a carbon dioxide recovery system in embodiment 5.

[0018] Figure 6 This is a schematic diagram of a carbon dioxide recovery system in embodiment 6.

[0019] Figure 7 This is a schematic diagram of a carbon dioxide recovery system in embodiment 7.

[0020] Figure 8 This is a schematic diagram of a carbon dioxide recovery system in embodiment 8.

[0021] Fig. 9 This is a schematic diagram of a carbon dioxide recovery system in Embodiment 9.

[0022] Fig.10 This is a schematic diagram of a carbon dioxide recovery system in embodiment 10.

[0023] Fig.11 This is a schematic diagram of a carbon dioxide recovery system in embodiment 11.

[0024] Fig.12 This is a schematic diagram of a carbon dioxide recovery system in embodiment 12. DETAILED DESCRIPTION

[0025] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. It should be noted that the scope of the present disclosure is not limited to the following embodiments, and any changes can be made within the scope of the technical concept of the present disclosure.

[0026] Implementation method 1.

[0027] Figure 1 This is a schematic diagram showing the carbon dioxide recovery system in Embodiment 1.

[0028] like Figure 1 As shown, the carbon dioxide recovery system 1 includes a supply path 2, a carbon dioxide adsorption unit 3, a derivation path 4, a regeneration path 5, a circulation path 6, a carbon dioxide separator 7, a heat pump unit (heat exchange unit) 8, an introduction path 9, a compressor 10 and a pressure reducer 11.

[0029] The supply path 2 is connected to the processing area 31 of the carbon dioxide adsorption unit 3. The supply path 2 guides air (processed fluid) such as external air to the processing area 31. The supply path 2 is provided with a blower 21 for sending air to the processing area 31, for example.

[0030] The carbon dioxide adsorption unit 3 includes a first region 31A and a second region 32A. Figure 1 In the example shown, the first region 31A is the treatment region 31. The second region 32A is the regeneration region 32. The treatment region 31 includes, for example, an adsorbent and a container for storing the adsorbent. The regeneration region 32 includes, for example, an adsorbent to be regenerated and a container for storing the adsorbent.

[0031] As adsorbents, amines, silica gel, zeolite, activated carbon, diatomaceous earth, alumina, etc. can be cited. Specifically, by making the adsorbent adsorb carbon dioxide contained in the air, it can be separated from other components. The adsorbent can be granular, powdery, etc. Granular, for example, is beaded (spherical), granular (cylindrical), etc. In the case of using a powdered adsorbent, the adsorbent can also be supported on the surface of the substrate. The substrate can also be honeycomb-shaped.

[0032] In the processing area 31 , at least a part of carbon dioxide contained in the air is removed by adsorption, so that air with a low carbon dioxide concentration can be obtained.

[0033] The regeneration area 32 regenerates the adsorbent that has adsorbed carbon dioxide in the treatment area 31 using the regeneration fluid F1. The regeneration area 32 has a function of desorbing carbon dioxide from the adsorbent. The regeneration area 32 is provided with, for example, a heating device for heating the adsorbent. The heating device desorbs carbon dioxide from the adsorbent by heating the adsorbent in the presence of the regeneration fluid F1. By desorbing carbon dioxide, the adsorbent is regenerated. The regeneration fluid F1 containing carbon dioxide desorbed from the adsorbent is discharged from the regeneration area 32 as a "regeneration discharge fluid F2".

[0034] The regeneration zone 32 may be provided with a decompression device such as a decompression pump. The decompression device promotes the desorption of carbon dioxide from the adsorbent by placing the adsorbent under a reduced pressure.

[0035] The outlet path 4 is connected to the processing area 31. The outlet path 4 supplies the air having a carbon dioxide concentration reduced by passing through the processing area 31 to the living space (supplied space) 100.

[0036] The regeneration path 5 connects the regeneration region 32 of the carbon dioxide adsorbing unit 3 and the carbon dioxide separator 7. The regeneration path 5 guides the regeneration fluid F1 from the carbon dioxide separator 7 to the regeneration region 32. Examples of the regeneration fluid F1 include nitrogen (N2), hydrogen (H2), and methane.

[0037] The circulation path 6 connects the regeneration region 32 of the carbon dioxide adsorption unit 3 and the carbon dioxide separator 7. The circulation path 6 guides the regeneration exhaust fluid F2 exhausted from the regeneration region 32 to the carbon dioxide separator 7.

[0038] The carbon dioxide separator 7 separates at least a portion of the carbon dioxide contained in the regeneration exhaust fluid F2 using a separation method such as liquefaction separation, membrane separation, and adsorption separation. The carbon dioxide separator 7 may use one of these separation methods or a combination of two or more.

[0039] The carbon dioxide separator 7 using liquefaction separation liquefies a specific component and separates it from other components (gases), for example. Specifically, for example, carbon dioxide is liquefied under high pressure and low temperature conditions and separated from other components (gases).

[0040] The carbon dioxide separator 7 using membrane separation uses, for example, a separation membrane through which components with small molecular sizes can pass, to separate specific components from other components. Specifically, for example, a separation membrane that selectively allows carbon dioxide to pass is used. The separation membrane separates carbon dioxide from a mixed fluid containing carbon dioxide and other components (nitrogen, hydrogen, methane, etc.). As separation membranes, organic membranes (dendritic polymer membranes, etc.) and inorganic membranes (zeolite membranes, silicon dioxide membranes, carbon membranes, etc.) can be cited.

[0041] The carbon dioxide separator 7 using adsorption separation performs separation by, for example, allowing an adsorbent to adsorb a specific component. Examples of the adsorbent include amines, silica gel, zeolite, activated carbon, diatomaceous earth, and alumina. Specifically, for example, carbon dioxide can be separated from other components by allowing the adsorbent to adsorb carbon dioxide.

[0042] The regeneration exhaust fluid F2 whose carbon dioxide concentration is reduced by separating carbon dioxide is guided out from the carbon dioxide separator 7 through the regeneration path 5 as the “regeneration fluid F1”.

[0043] The heat pump unit 8 includes a heater (first heat exchanger) 81 , an expander 82 , a cooler (second heat exchanger) 83 , a compressor 84 , and a circulation path 85 .

[0044] The heater 81 heats the regeneration fluid F1 by exchanging heat with the heat medium fluid F3.

[0045] The expander 82 reduces the pressure of the heat medium fluid F3.

[0046] The cooler 83 cools the regeneration exhaust fluid F2 by exchanging heat with the heat medium fluid F3.

[0047] The compressor 84 increases the pressure of the heat medium fluid F3.

[0048] The heater 81 , the expander 82 , the cooler 83 , and the compressor 84 are provided in the circulation path 85 .

[0049] The circulation path 85 is an annular path. The circulation path 85 circulates the heat medium fluid F3. The heat medium fluid F3 circulates in a manner that passes through the heater 81, the expander 82, the cooler 83, and the compressor 84 in sequence. Examples of the heat medium fluid F3 include carbon dioxide, a freon substitute, propane, dimethyl ether, and the like.

[0050] When carbon dioxide is used as the heat medium fluid F3, an appropriate heating temperature (eg, 90°C to 120°C) of the heater 81 and an appropriate cooling temperature (eg, -30°C to -20°C) of the cooler 83 can be achieved by applying the existing heat pump unit 8.

[0051] The heat pump unit 8 may also constitute an air conditioner, for example. The air conditioner performs at least one of cooling and heating by absorbing or radiating heat of the heat medium fluid F3. The heater 81 is provided, for example, in one of the indoor unit and the outdoor unit. The cooler 83 is provided, for example, in the other of the indoor unit and the outdoor unit.

[0052] The heat pump unit 8 may constitute, for example, a refrigerator-freezer device. The refrigerator-freezer device uses the heat absorbed by the heat medium fluid F3 to perform cooling via the cooler 83.

[0053] The introduction path 9 is connected to the supply path 2 . The introduction path 9 introduces the indoor air exhausted from the living space 100 into the supply path 2 .

[0054] The compressor 10 is provided in the circulation path 6. The compressor 10 increases the pressure of the regeneration exhaust fluid F2.

[0055] The decompressor 11 is provided in the regeneration path 5. The decompressor 11 decompresses the regeneration fluid F1.

[0056] On the downstream side of the compressor 10 , a cooler may be provided in order to lower the temperature of the regeneration discharge fluid F2 which has reached a high temperature due to the pressure increase by the compressor 10 .

[0057] Next, an example of a carbon dioxide recovery method using the carbon dioxide recovery system 1 will be described.

[0058] Air such as outside air is guided to the processing area 31 of the carbon dioxide adsorption unit 3 through the supply path 2. In the processing area 31, the carbon dioxide contained in the air is adsorbed by the adsorbent, thereby removing at least a part of the carbon dioxide. The air with a lower concentration of carbon dioxide is supplied to the living space (supplied space) 100 through the outlet path 4.

[0059] The step of removing at least a portion of carbon dioxide by adsorption in the processing region 31 is referred to as an “adsorption step”.

[0060] The adsorbent adsorbing carbon dioxide in the treatment area 31 is regenerated in the regeneration area 32. Specifically, in the regeneration area 32, carbon dioxide is desorbed from the adsorbent in the presence of the regeneration fluid F1. The adsorbent is regenerated by desorbing carbon dioxide. The regeneration fluid F1 containing carbon dioxide desorbed from the adsorbent is discharged from the regeneration area 32 as a "regeneration discharge fluid F2".

[0061] The step of regenerating the adsorbent in the regeneration zone 32 is referred to as a “regeneration step”.

[0062] Switching between the treatment region and the regeneration region in the carbon dioxide adsorption unit 3 will be described.

[0063] When the adsorbent that adsorbed carbon dioxide in the treatment area 31 is regenerated in the regeneration area 32, the adsorbent can be replaced between the treatment area 31 and the regeneration area 32. For example, the adsorbent in the treatment area 31 is moved to the regeneration area 32 together with the container, and the adsorbent regenerated in the regeneration area 32 is moved to the treatment area 31 together with the container. In this way, the treatment area and the regeneration area can be switched.

[0064] The adsorbent may be replaced by taking out the adsorbent in the treatment area 31 from the container and moving it to the regeneration area 32 , and taking out the adsorbent regenerated in the regeneration area 32 from the container and moving it to the treatment area 31 .

[0065] The processing area and regeneration area can also be switched by changing the path. Figure 1 In the first region 31A ( Figure 1 The left part in the figure is the processing area 31. The supply path 2 and the outlet path 4 are connected to the first area 31A. The second area 32A ( Figure 1 The right part in the figure is the regeneration area 32. The regeneration path 5 and the circulation path 6 are connected to the second area 32A.

[0066] By operating a valve provided in a branch path (not shown), the supply path 2 and the derivation path 4 are connected to the second region 32A. The regeneration path 5 and the circulation path 6 are connected to the first region 31A. By this operation, the first region 31A becomes the regeneration region. The second region 32A becomes the processing region. In this way, the processing region and the regeneration region can be switched. The first region 31A can also be returned to the processing region by operating a valve. The second region 32A can also be returned to the regeneration region.

[0067] The regeneration exhaust fluid F2 is led out from the regeneration area 32 through the circulation path 6. The pressure of the regeneration exhaust fluid F2 is increased by the compressor 10. The regeneration exhaust fluid F2 is cooled by heat exchange with the heat medium fluid F3 in the cooler 83. The cooler 83 can cool the regeneration exhaust fluid F2 to a temperature corresponding to the specification of the carbon dioxide separator 7 described later, for example, in the carbon dioxide separator 7.

[0068] The regeneration exhaust fluid F2 is directed to the carbon dioxide separator 7 .

[0069] The carbon dioxide separator 7 separates at least a portion of the carbon dioxide contained in the regeneration exhaust fluid F2 by using a separation method such as liquefaction separation, membrane separation, and adsorption separation. The concentrated carbon dioxide is recovered through a recovery path 71 .

[0070] The regeneration exhaust fluid F2 whose carbon dioxide concentration is reduced by separating carbon dioxide is guided out from the carbon dioxide separator 7 through the regeneration path 5 as the “regeneration fluid F1”.

[0071] The regeneration fluid F1 is heated by heat exchange with the heat medium fluid F3 in the heater 81. The heater 81 can heat the regeneration fluid F1 so that the temperature of the regeneration fluid F1 in the regeneration area 32 becomes 90° C. to 120° C., for example. The regeneration fluid F1 is decompressed in the decompressor 11 as needed. The regeneration fluid F1 is introduced into the regeneration area 32 through the regeneration path 5.

[0072] In the heat pump unit 8, the heat medium fluid F3 circulates in the circulation path 85. The heat medium fluid F3 is cooled by heat exchange with the regeneration fluid F1 in the heater 81. The heat medium fluid F3 is decompressed in the expander 82. The heat medium fluid F3 is heated by heat exchange with the regeneration exhaust fluid F2 in the cooler 83. After the heat medium fluid F3 is pressurized by the compressor 84, it flows to the heater 81. In this way, the heat medium fluid F3 heats the regeneration fluid F1 and cools the regeneration exhaust fluid F2.

[0073] The carbon dioxide recovery system 1 includes: a circulation path 6 for guiding the regeneration exhaust fluid F2 from the regeneration area 32, and a carbon dioxide separator 7 for generating a regeneration fluid F1 with a low carbon dioxide concentration from the regeneration exhaust fluid F2. The carbon dioxide recovery system 1 circulates the regeneration fluid F1, thereby improving the recovery efficiency of carbon dioxide in the carbon dioxide separator 7.

[0074] The carbon dioxide recovery system 1 circulates and uses the regeneration fluid F1 and the regeneration exhaust fluid F2, and therefore can effectively utilize the thermal energy of the regeneration fluid F1 and the regeneration exhaust fluid F2, thereby improving the energy efficiency of the entire system.

[0075] The carbon dioxide recovery system 1 recovers carbon dioxide from the air by the carbon dioxide adsorption unit 3 and guides the regeneration exhaust fluid F2 containing carbon dioxide to the carbon dioxide separator 7, so that the recovery efficiency of carbon dioxide can be improved.

[0076] The carbon dioxide recovery system 1 includes a compressor 10, a heater 81, and a cooler 83. The heater 81 heats the regeneration fluid F1 to make the temperature in the regeneration region 32 appropriate, thereby enabling efficient regeneration of the adsorbent. The compressor 10 increases the pressure of the regeneration exhaust fluid F2 to efficiently separate carbon dioxide in the carbon dioxide separator 7. The cooler 83 cools the regeneration exhaust fluid F2 to make the temperature in the carbon dioxide separator 7 appropriate, thereby enabling efficient separation of carbon dioxide.

[0077] The carbon dioxide recovery system 1 can reduce the volume of the regeneration exhaust fluid F2 by the compressor 10 and the cooler 83 , and thus can achieve miniaturization of the device.

[0078] The heater 81 heats the regeneration fluid F1 by heat exchange with the heat medium fluid F3. The cooler 83 cools the regeneration exhaust fluid F2 by heat exchange with the heat medium fluid F3. The carbon dioxide recovery system 1 performs heat exchange with the regeneration fluid F1 and the regeneration exhaust fluid F2 via the common heat medium fluid F3, thereby improving energy efficiency.

[0079] The carbon dioxide separator 7 using liquefaction separation can efficiently separate carbon dioxide. The carbon dioxide separator 7 using liquefaction separation can reduce the volume of carbon dioxide by liquefaction, and thus can achieve miniaturization of the device.

[0080] The carbon dioxide separator 7 using membrane separation can efficiently separate carbon dioxide. Compared with the case of using other separation methods, the carbon dioxide separator 7 using membrane separation has fewer restrictions on pressure, temperature, etc. Therefore, the energy used for pressurization, cooling, etc. can be suppressed. Therefore, carbon dioxide can be recovered at a low cost.

[0081] When carbon dioxide is used as the heat medium fluid F3, an appropriate heating temperature (e.g., 90°C to 120°C) of the heater 81 and an appropriate cooling temperature (e.g., -30°C to -20°C) of the cooler 83 can be achieved by applying the existing heat pump unit 8. Therefore, the carbon dioxide recovery system 1 can be constructed at low cost.

[0082] The heater 81 and the cooler 83 may at least constitute an air conditioner. In this case, the carbon dioxide recovery system 1 can be constructed using the heater 81 and the cooler 83 of the air conditioner, so that cost reduction can be achieved compared to the case of using dedicated heaters and coolers.

[0083] The heater 81 and the cooler 83 may at least constitute a refrigerator. In this case, the heater 81 and the cooler 83 of the refrigerator can be used to construct the carbon dioxide recovery system 1, so that cost reduction can be achieved compared to the case of using a dedicated heater and cooler.

[0084] The heater 81 and the cooler 83 may constitute both an air-conditioning device and a freezing / refrigerating device.

[0085] Implementation method 2.

[0086] Next, a carbon dioxide recovery system according to Embodiment 2 will be described. The carbon dioxide recovery system according to this embodiment has the same structure as Embodiment 1, and therefore, the differences from Embodiment 1 will be mainly described. The same structures as Embodiment 1 are denoted by the same reference numerals and description thereof will be omitted.

[0087] Figure 2 This is a schematic diagram of a portion of a carbon dioxide recovery system of Embodiment 2.

[0088] like Figure 2 As shown, the carbon dioxide recovery system 101 includes a heat pump unit 108 instead of the heat pump unit 8 (see Figure 1 ). The heat pump unit 108 replaces the compressor 84 (refer to Figure 1 ) and the plurality of compressors 184A, 184B are provided in the heat pump unit 8 (see Figure 1 ) are different. Compressors 184A and 184B are provided in the circulation path 85. Compressor 184A is a first compressor 184A. Compressor 184B is a second compressor 184B. The second compressor 184B is located downstream of the first compressor 184A in the flow direction of the heat medium fluid F3. The first compressor 184A and the second compressor 184B are arranged in series in the circulation path 85.

[0089] Since the heat pump unit 108 of the carbon dioxide recovery system 101 includes a plurality of compressors 184A and 184B, the pressure of the heat medium fluid F3 can be increased. Therefore, the range of heating and cooling operations in the heat pump unit 108 can be expanded. Therefore, the performance as a carbon dioxide recovery system can be improved, and carbon dioxide can be recovered efficiently.

[0090] It should be noted that in Figure 2In the carbon dioxide recovery system 101 shown, the number of compressors of the heat pump unit 108 is two, but the number of compressors is not limited to two. The number of compressors may be plural (any number of 2 or more).

[0091] Implementation method 3.

[0092] Next, a description will be given of a carbon dioxide recovery system according to Embodiment 3. The same components as those in other embodiments are denoted by the same reference numerals and description thereof will be omitted.

[0093] Figure 3 This is a schematic diagram of a portion of a carbon dioxide recovery system of embodiment 3.

[0094] like Figure 3 As shown, the carbon dioxide recovery system 201 includes a heat pump unit 208 instead of the heat pump unit 8 (see Figure 1 ).

[0095] The heat pump unit 208 includes a heater (first heat exchanger) 281 , a first expander 282 , an intermediate heat exchanger 287 , a first compressor 284 , a first circulation path 285 , a second expander 288 , a cooler (second heat exchanger) 283 , a second compressor 289 , and a second circulation path 290 .

[0096] The heater 281 heats the regeneration fluid F1 by exchanging heat with the first heat medium fluid F3A.

[0097] The first expander 282 reduces the pressure of the first heat medium fluid F3A.

[0098] The intermediate heat exchanger 287 cools the second heat medium fluid F3B by exchanging heat with the first heat medium fluid F3A.

[0099] The first compressor 284 increases the pressure of the first heat medium fluid F3A.

[0100] The heater 281 , the first expander 282 , the intermediate heat exchanger 287 , and the first compressor 284 are provided in the first circulation path 285 .

[0101] The first circulation path 285 is a loop-shaped path and circulates the first heat medium fluid F3A through the heater 281 , the first expander 282 , the intermediate heat exchanger 287 , and the first compressor 284 in this order.

[0102] The second expander 288 reduces the pressure of the second heat medium fluid F3B.

[0103] The cooler 283 cools the regeneration exhaust fluid F2 by exchanging heat with the second heat medium fluid F3B.

[0104] The second compressor 289 increases the pressure of the second heat medium fluid F3B.

[0105] The intermediate heat exchanger 287 , the second expander 288 , the cooler 283 , and the second compressor 289 are provided in the second circulation path 290 .

[0106] The second circulation path 290 is a loop-shaped path and circulates the second heat medium fluid F3B in order through the intermediate heat exchanger 287 , the second expander 288 , the cooler 283 , and the second compressor 289 .

[0107] The first heat medium fluid F3A and the second heat medium fluid F3B have different physical properties such as boiling points. As the first heat medium fluid F3A, for example, carbon dioxide can be cited. As the second heat medium fluid F3B, for example, a freon substitute can be cited. The second heat medium fluid F3B is used at a lower temperature than the first heat medium fluid F3A, for example.

[0108] The portion (first portion) through which the first heat medium fluid F3A flows in the heat pump unit 208 can be constructed using a heat pump for a water heater, for example. The first portion includes, for example, a heater 281 , a first expander 282 , a first compressor 284 , and a first circulation path 285 .

[0109] The portion (second portion) in the heat pump unit 208 through which the second heat medium fluid F3B flows can be constructed using a heat pump for refrigeration, for example. The second portion includes, for example, a second expander 288 , a cooler 283 , a second compressor 289 , and a second circulation path 290 .

[0110] The intermediate heat exchanger 287 is included in one of the first section and the second section.

[0111] The carbon dioxide recovery system 201 includes a heat pump unit 208 having a heater 281, an intermediate heat exchanger 287, and a cooler 283. In the heat pump unit 208, since the first heat medium fluid F3A and the second heat medium fluid F3B are used, the operation range of heating and cooling can be expanded. Therefore, the performance as a carbon dioxide recovery system can be improved, and carbon dioxide can be recovered efficiently.

[0112] Implementation method 4.

[0113] Next, a description will be given of a carbon dioxide recovery system according to Embodiment 4. The same components as those in other embodiments are denoted by the same reference numerals and description thereof will be omitted.

[0114] Figure 4 This is a schematic diagram of a carbon dioxide recovery system in Embodiment 4.

[0115] like Figure 4 As shown, the carbon dioxide recovery system 301 is similar to the carbon dioxide recovery system 1 (see Figure 1 ) is that an air purifier 312 is provided in the introduction path 9.

[0116] The air purifier 312 purifies the air by, for example, capturing suspended matter such as pollen, dust, viruses, mold, bacteria, indoor dust, smoke, odorous substances, volatile chemicals, etc. The air purifier 312, for example, includes a filter for capturing suspended matter. The air purifier 312 may also include an electric field generating device for forming an electric field between electrodes. The electric field generating device can kill or inactivate pollen, viruses, mold, bacteria, etc.

[0117] The carbon dioxide recovery system 301 includes the air purifier 312, and thus can purify the indoor air exhausted from the living space 100 and introduce it into the supply path 2. Therefore, it is possible to improve the cleanliness of the air supplied to the living space 100. In the carbon dioxide recovery system 301, since the air supplied to the carbon dioxide adsorption unit 3 becomes clean, the recovery efficiency of carbon dioxide in the carbon dioxide adsorption unit 3 can be improved.

[0118] Implementation method 5.

[0119] Next, a description will be given of a carbon dioxide recovery system according to Embodiment 5. The same components as those in other embodiments are denoted by the same reference numerals and description thereof will be omitted.

[0120] Figure 5 This is a schematic diagram of a carbon dioxide recovery system in embodiment 5.

[0121] like Figure 5 As shown, the carbon dioxide recovery system 401 is the same as the carbon dioxide recovery system 1 (see Figure 1 ) is that an exhaust path 413 is connected to the lead-out path 4. The exhaust path 413 can discharge a part of the air flowing in the lead-out path 4 to the outside of the system. The gas discharged from the exhaust path 413 is discharged into the atmosphere, for example.

[0122] The carbon dioxide recovery system 401 can take in outside air from the supply path 2 by discharging a portion of the air flowing in the derivation path 4 from the exhaust path 413. By performing ventilation based on the discharge and intake of air, the cleanliness of the air in the living space 100 can be improved. The carbon dioxide recovery system 401 discharges the gas after the carbon dioxide is recovered from the exhaust path 413 into the atmosphere, so the emission of carbon dioxide can be suppressed to a low level. Therefore, it is preferable from the viewpoint of environmental protection.

[0123] Implementation method 6.

[0124] Next, a description will be given of a carbon dioxide recovery system according to Embodiment 6. The same components as those in other embodiments are denoted by the same reference numerals and description thereof will be omitted.

[0125] Figure 6 This is a schematic diagram of a carbon dioxide recovery system in embodiment 6.

[0126] like Figure 6 As shown, the carbon dioxide recovery system 501 is the same as the carbon dioxide recovery system 1 (refer to Figure 1 ) is that an air purifier 312 is provided in the inlet path 9, and an exhaust path 413 is connected to the outlet path 4.

[0127] The carbon dioxide recovery system 501 is provided with an air purifier 312, so that clean air can be introduced into the supply path 2. The carbon dioxide recovery system 501 is provided with an exhaust path 413, so that ventilation can be performed. Therefore, the cleanliness of the air in the living space 100 can be improved. The carbon dioxide recovery system 501 discharges the gas after the carbon dioxide is recovered from the exhaust path 413 into the atmosphere, so that the emission of carbon dioxide can be suppressed to a low level. Therefore, it is preferable from the viewpoint of environmental protection.

[0128] Implementation method 7.

[0129] Next, a description will be given of a carbon dioxide recovery system according to Embodiment 7. The same components as those in other embodiments are denoted by the same reference numerals and description thereof will be omitted.

[0130] Figure 7 This is a schematic diagram of a carbon dioxide recovery system in embodiment 7.

[0131] like Figure 7 As shown, the carbon dioxide recovery system 601 includes a carbon dioxide adsorption unit 603 instead of the carbon dioxide adsorption unit 3 (see Figure 1 ). The carbon dioxide adsorption unit 603 includes a first processing region 31 , a second processing region 633 , and a regeneration region 32 .

[0132] The first processing area 31 is the same as the processing area 31 (refer to Figure 1 )Same structure.

[0133] The second processing region 633 includes an adsorbent similar to the first processing region 31. The adsorbent of the second processing region 633 may be the same as the adsorbent of the first processing region 31.

[0134] The adsorbent in the first treatment area 31 and the second treatment area 633 can be regenerated through a regeneration process.

[0135] The second treatment area 633 is connected to the introduction path 9. The introduction path 9 guides the air exhausted from the living space 100 to the second treatment area 633. The second treatment area 633 removes at least a portion of the carbon dioxide contained in the air by adsorption. The air with a reduced concentration of carbon dioxide is exhausted from the second treatment area 633 to the outside of the system through the exhaust path 634.

[0136] Since the carbon dioxide recovery system 601 has the second processing area 633, it is possible to recover carbon dioxide contained in the air exhausted from the living space 100. Therefore, it is possible to improve the recovery efficiency of carbon dioxide.

[0137] In the carbon dioxide recovery system 601, the air exhausted from the living space 100 is not reused, but discharged to the outside of the system through the exhaust path 634. Therefore, the risk of airborne infection and droplet infection of infectious diseases caused by viruses and the like can be reduced. In addition, the cleanliness of the air in the living space 100 can be improved. The carbon dioxide recovery system 601 discharges the gas after the carbon dioxide is recovered from the exhaust path 413 into the atmosphere, so the emission of carbon dioxide can be suppressed to a low level. Therefore, it is preferred from the viewpoint of environmental protection.

[0138] Implementation method 8.

[0139] Next, a description will be given of a carbon dioxide recovery system according to Embodiment 8. The same components as those in other embodiments are denoted by the same reference numerals and description thereof will be omitted.

[0140] Figure 8 This is a schematic diagram of a carbon dioxide recovery system in embodiment 8.

[0141] like Figure 8 As shown, the carbon dioxide recovery system 701 and the carbon dioxide recovery system 601 (see Figure 7 ) is that a heat exchanger 714 is provided. The heat exchanger 714 is provided across the outlet path 4 and the inlet path 9. The heat exchanger 714 performs heat exchange and humidity exchange between the air supplied to the living space 100 through the outlet path 4 and the air discharged from the living space 100 through the inlet path 9. The heat exchanger 714 can make the air supplied to the living space 100 have a temperature and humidity corresponding to the environment in the living space 100.

[0142] Since the carbon dioxide recovery system 701 includes the heat exchanger 714, the air supplied to the living space 100 through the outlet path 4 can be temperature-controlled by heat exchange with the exhaust air to adjust the temperature and humidity thereof, thereby improving energy efficiency.

[0143] The carbon dioxide separator preferably adopts one or both of liquefaction separation and membrane separation. Hereinafter, configuration examples of the carbon dioxide recovery system are shown for the case of adopting liquefaction separation, the case of adopting membrane separation, and the case of adopting both liquefaction separation and membrane separation.

[0144] Implementation method 9.

[0145] A carbon dioxide recovery system according to Embodiment 9 will be described. The same components as those in other embodiments are denoted by the same reference numerals and description thereof will be omitted.

[0146] Fig. 9 This is a schematic diagram of a carbon dioxide recovery system in Embodiment 9.

[0147] like Fig. 9 As shown, in the carbon dioxide recovery system 801, the carbon dioxide separator 7 is a liquefaction separator that separates carbon dioxide by liquefaction separation. Since the carbon dioxide separator 7 is a liquefaction separator, high pressure and low temperature are required. The regenerated exhaust fluid F2 passes through the compressor 10 to become high pressure. The regenerated exhaust fluid F2 passes through the cooler 83 to become low temperature. The conditions for liquefying carbon dioxide are, for example, a temperature of -20 to -30°C and a pressure of 2MPa.

[0148] The carbon dioxide recovery system 801 includes a cooler 815. The cooler 815 is arranged on the downstream side of the compressor 10 in the circulation path 6. The cooler 815 is arranged, for example, between the compressor 10 and the cooler 83. The cooler 815 is, for example, a water-cooled cooler. The cooler 815 cools the regenerated exhaust fluid F2 by heat exchange with the refrigerant (water). The temperature of the regenerated exhaust fluid F2 rises due to the pressure increase based on the compressor 10, but the cooler 815 reduces the temperature of the regenerated exhaust fluid F2. Therefore, the load of the cooler 83 can be reduced.

[0149] The carbon dioxide separator 7 liquefies and separates at least a portion of carbon dioxide contained in the regeneration exhaust fluid F2 that has passed through the cooler 83 . The concentrated carbon dioxide is recovered through the recovery path 71 .

[0150] The carbon dioxide recovery system 801 adopts liquefaction separation, so it is possible to efficiently separate carbon dioxide. The carbon dioxide recovery system 801 can reduce the volume of carbon dioxide by liquefaction, so it is possible to achieve miniaturization of the device.

[0151] It should be noted that the cooler 815 is described as a water-cooled cooler, but the cooling method of the cooler is not limited thereto, and for example, cooling by circulating the regeneration fluid F1 may also be adopted. Thus, the regeneration fluid F1 is heated, and thus a system with higher thermal efficiency can be realized.

[0152] Implementation method 10.

[0153] Next, a description will be given of a carbon dioxide recovery system according to Embodiment 10. The same components as those in other embodiments are denoted by the same reference numerals and description thereof will be omitted.

[0154] Fig.10 This is a schematic diagram of a carbon dioxide recovery system in embodiment 10.

[0155] like Fig.10 As shown, in the carbon dioxide recovery system 901, the carbon dioxide separator 907 is a membrane separator that separates carbon dioxide by membrane separation. The carbon dioxide separator 907, for example, has a separation membrane that selectively allows carbon dioxide to pass through. The carbon dioxide separator 907 separates at least a portion of the carbon dioxide contained in the regeneration exhaust fluid F2 by membrane separation. The concentrated carbon dioxide is recovered through the recovery path 71.

[0156] Carbon dioxide recovery system 901 uses membrane separation, so it can efficiently separate carbon dioxide. Carbon dioxide recovery system 901 has fewer restrictions on pressure, temperature, etc. compared with other separation methods. It can suppress the energy used for pressurization, cooling, etc., so it can recover carbon dioxide at a low cost.

[0157] Implementation method 11.

[0158] Next, a description will be given of a carbon dioxide recovery system according to Embodiment 11. The same components as those in other embodiments are denoted by the same reference numerals and description thereof will be omitted.

[0159] Fig.11 This is a schematic diagram of a carbon dioxide recovery system in embodiment 11.

[0160] like Fig.11 As shown, in the carbon dioxide recovery system 1001, as a method of separating carbon dioxide in the carbon dioxide separator, both liquefaction separation and membrane separation are adopted.

[0161] The carbon dioxide recovery system 1001 includes a supply path 2, a carbon dioxide adsorption unit 3, a derivation path 4, a regeneration path 5, a circulation path 6, a heat pump unit 8, an introduction path 9, a first compressor 10, a first cooler 1015, a first carbon dioxide separator 1007, a return path 1002, a second compressor 1010, a second cooler 1016, a second carbon dioxide separator 7, and a pressure reducer 11. The first carbon dioxide separator 1007 and the second carbon dioxide separator 7 are examples of carbon dioxide separators.

[0162] Carbon dioxide recovery system 1001 and carbon dioxide recovery system 1 (refer to Figure 1) is different in that it includes a first cooler 1015, a first carbon dioxide separator 1007, a return path 1002, a second compressor 1010 and a second cooler 1016.

[0163] The first cooler 1015 and the second cooler 1016 are, for example, water-cooled coolers. The first cooler 1015 and the second cooler 1016 cool the fluid by heat exchange with the refrigerant (water).

[0164] The first carbon dioxide separator 1007 is a membrane separator. The first carbon dioxide separator 1007 has, for example, a separation membrane that selectively allows carbon dioxide to pass through. The second carbon dioxide separator 7 is a liquefaction separator.

[0165] The return path 1002 connects the outlet on the non-permeation side of the first carbon dioxide separator 1007 to the circulation path 6 (a position upstream of the first compressor 10 ).

[0166] In the carbon dioxide recovery system 1001, the regeneration exhaust fluid F2 is pressurized by the first compressor 10, cooled by the first cooler 1015, and guided to the first carbon dioxide separator 1007. The carbon dioxide contained in the regeneration exhaust fluid F2 is concentrated by the first carbon dioxide separator 1007. The permeate side fluid F4 after the carbon dioxide is concentrated flows to the second compressor 1010.

[0167] The non-permeated fluid F5 that has not permeated the separation membrane of the first carbon dioxide separator 1007 is returned to the circulation path 6 (upstream of the first compressor 10) through the return path 1002. This can improve the separation efficiency of carbon dioxide in the first carbon dioxide separator 1007.

[0168] After the pressure of the permeate side fluid F4 is increased by the second compressor 1010, it is cooled by the second cooler 1016 and the cooler 83 and guided to the second carbon dioxide separator 7. The second carbon dioxide separator 7 liquefies and separates at least a part of the carbon dioxide contained in the permeate side fluid F4. The concentrated carbon dioxide is recovered through the recovery path 71.

[0169] The carbon dioxide recovery system 1001 can improve the recovery efficiency of carbon dioxide by adopting both liquefaction separation and membrane separation.

[0170] Here, the first cooler 1015 and the second cooler 1016 are described as water-cooled, but the present invention is not limited thereto, and for example, cooling by circulating the regeneration fluid F1 may be adopted. Thus, the regeneration fluid F1 is heated, and thus a system with higher thermal efficiency can be realized.

[0171] Implementation method 12.

[0172] Next, a description will be given of a carbon dioxide recovery system according to Embodiment 12. The same components as those in other embodiments are denoted by the same reference numerals and description thereof will be omitted.

[0173] Fig.12 This is a schematic diagram of a carbon dioxide recovery system in embodiment 12.

[0174] like Fig.12 As shown, the carbon dioxide recovery system 1101 and the carbon dioxide recovery system 1001 (refer to Fig.11 ) is different in that a return path 1102 is provided instead of the return path 1002 (see Fig.11 ).

[0175] The return path 1102 connects the outlet of the non-permeable side of the first carbon dioxide separator 1007 to the regeneration path 5 (a position upstream of the heater 81). The non-permeable side fluid F5 discharged from the first carbon dioxide separator 1007 is guided to the regeneration path 5 through the return path 1102. The non-permeable side fluid F5 is used as a part of the regeneration fluid F1.

[0176] The carbon dioxide recovery system 1101 can improve the recovery efficiency of carbon dioxide by using both liquefaction separation and membrane separation. The carbon dioxide recovery system 1101 performs membrane separation before liquefaction separation, so the energy required for cooling for liquefaction separation can be suppressed. Therefore, carbon dioxide can be recovered at a low cost.

[0177] In the carbon dioxide recovery system 1101, since the non-permeated side fluid F5 having a low carbon dioxide concentration is used as the regeneration fluid F1, energy efficiency can be improved.

[0178] It should be noted that the technical scope of the present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present disclosure.

[0179] For example, one or more concentrators may be provided in the circulation path 6. The concentrator increases the concentration of carbon dioxide in the regenerated exhaust fluid F2 by, for example, liquefaction separation, membrane separation, adsorption separation, etc. Therefore, the energy efficiency in the carbon dioxide separator 7 can be improved. The concentrator may also be provided in the supply path 2. In addition, the pressure reducer 11 is provided on the downstream side of the heater 81, but is not limited thereto, and may also be provided on the upstream side of the heater 81 according to the system equipment specifications.

[0180] As the heat exchanger such as the heater, the cooler, the intermediate heat exchanger, a known heat exchanger can be used. As the heat exchanger, for example, a multi-tube heat exchanger, a plate heat exchanger, a coil heat exchanger, a double tube heat exchanger, a spiral heat exchanger, etc. can be used.

[0181] Although air is exemplified as the fluid to be processed, the carbon dioxide recovery system of the embodiment can also be applied to fluids to be processed other than air (nitrogen, hydrogen, oxygen, methane, etc.).

[0182] Description of Reference Numerals

[0183] 1, 101, 201, 301, 401, 501, 601, 701, 801, 901, 1001, 1101 carbon dioxide recovery system 2 supply path 3 carbon dioxide adsorption unit 4 export path 5 regeneration path 6 circulation path 7, 907 carbon dioxide separator 9 inlet path 10 compressor 31 treatment area 32 regeneration area 81, 281 heater 83, 283 cooler 84 compressor 184A first compressor (compressor) 184B second compressor (compressor) 287 intermediate heat exchanger 413 exhaust path 1007 first carbon dioxide separator (carbon dioxide separator) F1 regeneration fluid F2 regeneration exhaust fluid.

Claims

1. A carbon dioxide recovery system, wherein: The carbon dioxide recovery system comprises: a supply path that guides air; a carbon dioxide adsorption unit having a treatment region for causing an adsorbent to adsorb carbon dioxide contained in the air and a regeneration region for regenerating the adsorbent using a regeneration fluid; a lead-out path for guiding the air having a reduced concentration of carbon dioxide through the treatment area; a regeneration path that guides the regeneration fluid to the regeneration area; a circulation path that guides a regeneration exhaust fluid that is exhausted by regenerating the adsorbent using the regeneration fluid; as well as A carbon dioxide separator is provided for obtaining the regeneration fluid by separating at least a part of carbon dioxide from the regeneration exhaust fluid.

2. The carbon dioxide recovery system according to claim 1, wherein: The carbon dioxide recovery system also has: a heater for heating the regeneration fluid; a cooler that cools the regeneration exhaust fluid; and A compressor increases the pressure of the regeneration exhaust fluid.

3. The carbon dioxide recovery system according to claim 2, wherein: The heater heats the regeneration fluid by heat exchange with the heat medium fluid. The cooler cools the regeneration exhaust fluid by exchanging heat with the heat medium fluid.

4. The carbon dioxide recovery system according to claim 2, wherein: The carbon dioxide recovery system further comprises an intermediate heat exchanger, The heater heats the regeneration fluid by heat exchange with the first heat medium fluid. The intermediate heat exchanger cools the second heat medium fluid by exchanging heat with the first heat medium fluid. The cooler cools the regeneration exhaust fluid by exchanging heat with the second heat medium fluid.

5. The carbon dioxide recovery system according to any one of claims 1 to 4, wherein: The carbon dioxide separator separates carbon dioxide contained in the regeneration exhaust fluid by liquefaction separation.

6. The carbon dioxide recovery system according to any one of claims 1 to 4, wherein: The carbon dioxide separator separates carbon dioxide contained in the regeneration exhaust fluid by membrane separation.

7. The carbon dioxide recovery system according to claim 3, wherein: The heat medium fluid is carbon dioxide.

8. The carbon dioxide recovery system according to claim 3, wherein: The heater and the cooler constitute at least an air conditioning device.

9. The carbon dioxide recovery system according to claim 3, wherein: The heater and the cooler at least constitute a freezer-refrigerator unit.

10. The carbon dioxide recovery system according to any one of claims 1 to 9, wherein: The outlet path is connected to an exhaust path for exhausting a part of the air flowing in the outlet path.

Images