Carbon dioxide capture system

Abstract

The invention proposes a carbon dioxide capture system (10) comprising a supply line (11) configured to supply air compressed by a compressor (12) to a pneumatic device (13), and a carbon dioxide capture device (15) configured to separate and capture carbon dioxide from air compressed by a compressor (12). The carbon dioxide capture device (15) is positioned between the compressor (12) and the pneumatic device (13) on the supply line (11).

Description

Carbon dioxide capture system

[0001] The present disclosure relates to carbon dioxide capture systems.

[0002] In recent years, with the promotion of carbon neutrality, it has been considered to separate and capture carbon dioxide contained in air from the air and utilize the captured carbon dioxide in various fields. As a technology for separating and capturing carbon dioxide contained in air from the air (Direct Air Capture), for example, a carbon dioxide capture device described in Patent Document 1 is known.

[0003] JP 2023-45570 A

[0004] The conventional technology described in Patent Document 1 employs a method in which large, dedicated facilities are newly installed from scratch just for the purpose of separating and capturing carbon dioxide from air. Therefore, it is desired to efficiently capture carbon dioxide while minimizing facility costs as much as possible, without installing large, dedicated facilities from scratch just for the purpose of capturing carbon dioxide.

[0005] A carbon dioxide capture system according to one aspect of the present disclosure includes a supply line configured to supply air compressed by a compressor to a pneumatic device, and a carbon dioxide capture device configured to separate and capture carbon dioxide from the air compressed by the compressor. The carbon dioxide capture device is provided in the supply line between the compressor and the pneumatic device.

[0006] FIG. 1 is a circuit diagram for explaining a carbon dioxide capture system according to an embodiment.

[0007] An embodiment of a carbon dioxide capture system 10 will be described below with reference to Fig. 1. The carbon dioxide capture system 10 of this embodiment is used in a factory. <Outline of Carbon Dioxide Capture System> As shown in Fig. 1, the carbon dioxide capture system 10 includes a supply line 11. The supply line 11 supplies air compressed by a compressor 12 to pneumatic equipment 13. The supply line 11 of this embodiment is an existing facility for supplying air compressed by the compressor 12 to pneumatic equipment 13 used in a factory.

[0008] The supply line 11 has a conditioning device 14. The conditioning device 14 removes moisture and foreign matter contained in the air compressed by the compressor 12. A carbon dioxide capture device 15 is provided in the supply line 11 between the compressor 12 and the pneumatic equipment 13. The carbon dioxide capture device 15 is provided in the supply line 11 between the conditioning device 14 and the pneumatic equipment 13. The carbon dioxide capture device 15 separates and captures carbon dioxide from the air compressed by the compressor 12.

[0009] The compressor 12 has an intake port 12a and an exhaust port 12b. The conditioning equipment 14 has a supply port 14a and an exhaust port 14b. The carbon dioxide capture device 15 has a housing 16. The housing 16 has an inlet 16a and an outlet 16b.

[0010] The carbon dioxide capture system 10 includes a first supply pipe 17, a second supply pipe 18, and a third supply pipe 19. A first end of the first supply pipe 17 is connected to the discharge port 12b of the compressor 12. A second end of the first supply pipe 17 is connected to the supply port 14a of the conditioning equipment 14. The first supply pipe 17 connects the discharge port 12b of the compressor 12 and the supply port 14a of the conditioning equipment 14 to each other. A first end of the second supply pipe 18 is connected to the discharge port 14b of the conditioning equipment 14. A second end of the second supply pipe 18 is connected to the inlet 16a of the housing 16. The second supply pipe 18 connects the discharge port 14b of the conditioning equipment 14 to the inlet 16a of the housing 16 to each other. A first end of the third supply pipe 19 is connected to the outlet 16b of the housing 16. A second end of the third supply pipe 19 is connected to the pneumatic equipment 13. The third supply pipe 19 connects the outlet 16 b of the housing 16 and the pneumatic device 13 to each other.

[0011] The inlet 16a of the housing 16 is configured to be detachable from the second end of the second supply pipe 18. The outlet 16b of the housing 16 is configured to be detachable from the first end of the third supply pipe 19. Therefore, the housing 16 is configured to be detachable from the second supply pipe 18 and the third supply pipe 19.

[0012] The carbon dioxide capture device 15 has a main pipe 20. The main pipe 20 is disposed inside the housing 16. A first end of the main pipe 20 is connected to the inlet 16a of the housing 16. A second end of the main pipe 20 is connected to the outlet 16b of the housing 16. The main pipe 20 connects the inlet 16a and the outlet 16b of the housing 16 to each other. The first supply pipe 17, the second supply pipe 18, the main pipe 20, and the third supply pipe 19 constitute the supply line 11.

[0013] <Carbon dioxide capture device> The carbon dioxide capture device 15 has a plurality of separators 21. Each separator 21 is disposed inside the housing 16. Each separator 21 separates carbon dioxide from air compressed by the compressor 12. In this embodiment, the carbon dioxide capture device 15 has four separators 21. In the following description, the four separators 21 may be referred to as "first separator 21A," "second separator 21B," "third separator 21C," and "fourth separator 21D," respectively.

[0014] Each separation device 21 has a separation element 22 and a suction pump 23. The separation element 22 separates carbon dioxide from air in each separation device 21. The separation element 22 separates carbon dioxide from air by membrane separation. Therefore, the carbon dioxide capture device 15 separates carbon dioxide from air by membrane separation. Membrane separation is a technique in which air passes through a membrane to filter and extract carbon dioxide. The suction pump 23 sucks the carbon dioxide separated from the air by the separation element 22 in each separation device 21. Specifically, the suction pump 23 sucks air with a high proportion of carbon dioxide.

[0015] The separation element 22 of the first separation device 21A is provided in the main pipe 20. The carbon dioxide capture device 15 has a first return pipe 31, a second return pipe 32, and a third return pipe 33. The first return pipe 31, the second return pipe 32, and the third return pipe 33 are arranged inside the housing 16. A first end of the first return pipe 31 is connected to the separation element 22 of the second separation device 21B. A second end of the first return pipe 31 is connected to a portion of the main pipe 20 between a location where the separation element 22 of the first separation device 21A is provided and the outlet 16b. A first end of the second return pipe 32 is connected to the separation element 22 of the third separation device 21C. A second end of the second return pipe 32 is connected to a portion of the main pipe 20 between a location where the separation element 22 of the first separation device 21A is connected to the outlet 16b. A first end of the third return pipe 33 is connected to the separation element 22 of the fourth separation device 21D. A second end of the third return pipe 33 is connected to a portion of the main pipe 20 between the connection point with the second return pipe 32 and the outlet 16b.

[0016] Each of the first separator 21A, second separator 21B, and third separator 21C has a tank 24 and a pressure regulating valve 25. The tank 24 stores the carbon dioxide sucked by the suction pump 23 in each separator 21. Specifically, the tank 24 stores air with a high proportion of carbon dioxide. The pressure regulating valve 25 maintains the pressure inside the tank 24 at a constant level in each separator 21.

[0017] In the first separation device 21A, the separation element 22 and the suction pump 23 are connected to each other by a first pipe 41. In the first separation device 21A, the suction pump 23 and the tank 24 are connected to each other by a second pipe 42. In the first separation device 21A, the tank 24 and the pressure regulating valve 25 are connected to each other by a third pipe 43.

[0018] In the second separation device 21B, the separation element 22 and the suction pump 23 are connected to each other by a fourth pipe 44. In the second separation device 21B, the suction pump 23 and the tank 24 are connected to each other by a fifth pipe 45. In the second separation device 21B, the tank 24 and the pressure regulating valve 25 are connected to each other by a sixth pipe 46.

[0019] In the third separation device 21C, the separation element 22 and the suction pump 23 are connected to each other by a seventh pipe 47. In the third separation device 21C, the suction pump 23 and the tank 24 are connected to each other by an eighth pipe 48. In the third separation device 21C, the tank 24 and the pressure regulating valve 25 are connected to each other by a ninth pipe 49.

[0020] The fourth separation device 21D has a storage element 26. The storage element 26 is, for example, a tank. The storage element 26 stores the carbon dioxide sucked by the suction pump 23 in the fourth separation device 21D. Specifically, the storage element 26 stores air with a high proportion of carbon dioxide.

[0021] In the fourth separation device 21D, the separation element 22 and the suction pump 23 are connected to each other by a tenth pipe 50. In the fourth separation device 21D, the suction pump 23 and the storage element 26 are connected to each other by an eleventh pipe 51. The eleventh pipe 51 is a connecting pipe that connects the suction pump 23 and the storage element 26 to each other. The storage element 26 is configured to be detachable from the eleventh pipe 51.

[0022] The pressure regulating valve 25 of the first separator 21A and the separation element 22 of the second separator 21B are connected to each other by a first connecting pipe 61. The pressure regulating valve 25 of the second separator 21B and the separation element 22 of the third separator 21C are connected to each other by a second connecting pipe 62. The pressure regulating valve 25 of the third separator 21C and the separation element 22 of the fourth separator 21D are connected to each other by a third connecting pipe 63. Thus, the multiple separators 21 are connected in series. The fourth separator 21D is the separation device located at the most downstream position among the multiple separators 21. The first separator 21A, the second separator 21B, and the third separator 21C are the separation devices 21 that are not located at the most downstream position among the multiple separators 21. The pressure regulating valve 25 outputs carbon dioxide in the tank 24 to the separation element 22 of the separator 21 immediately downstream.

[0023] [Operation of the Embodiment] Next, the operation of the present embodiment will be described. The compressor 12 draws air through the intake port 12a and compresses the drawn air. The air compressed by the compressor 12 is discharged into the first supply pipe 17 through the discharge port 12b. The air discharged into the first supply pipe 17 is supplied to the conditioning device 14 through the supply port 14a. The conditioning device 14 removes moisture and foreign matter from the supplied air. The air from which moisture and foreign matter have been removed by the conditioning device 14 flows into the main pipe 20 through the discharge port 14b, the second supply pipe 18, and the inlet 16a.

[0024] The separation element 22 of the first separator 21A separates carbon dioxide from the air that has flowed into the main pipe 20 via the inlet 16a. The air from which carbon dioxide has been separated by the separation element 22 of the first separator 21A flows through the main pipe 20 toward the outlet 16b. Meanwhile, the carbon dioxide separated from the air by the separation element 22, i.e., the air with a high carbon dioxide content, is sucked by the suction pump 23 of the first separator 21A via the first pipe 41 and stored in the tank 24 via the second pipe 42. The pressure regulating valve 25 of the first separator 21A outputs the air with a high carbon dioxide content stored in the tank 24 to the separation element 22 of the second separator 21B via the third pipe 43 and the first connecting pipe 61.

[0025] The separation element 22 of the second separator 21B separates carbon dioxide from the air output to the separation element 22 of the second separator 21B via the first connecting pipe 61. The air from which carbon dioxide has been separated by the separation element 22 of the second separator 21B is returned to the main pipe 20 via the first return pipe 31 and flows through the main pipe 20 toward the outlet 16b. Meanwhile, the carbon dioxide separated from the air by the separation element 22, i.e., the air with a high carbon dioxide content, is sucked by the suction pump 23 of the second separator 21B via the fourth pipe 44 and stored in the tank 24 via the fifth pipe 45. The pressure regulating valve 25 of the second separator 21B outputs the air with a high carbon dioxide content stored in the tank 24 to the separation element 22 of the third separator 21C via the sixth pipe 46 and the second connecting pipe 62.

[0026] The separation element 22 of the third separator 21C separates carbon dioxide from the air output to the separation element 22 of the third separator 21C via the second connecting pipe 62. The air from which carbon dioxide has been separated by the separation element 22 of the third separator 21C is returned to the main pipe 20 via the second return pipe 32 and flows through the main pipe 20 toward the outlet 16b. Meanwhile, the carbon dioxide separated from the air by the separation element 22, i.e., the air with a high carbon dioxide content, is sucked by the suction pump 23 of the third separator 21C via the seventh pipe 47 and stored in the tank 24 via the eighth pipe 48. The pressure regulating valve 25 of the third separator 21C outputs the air with a high carbon dioxide content stored in the tank 24 to the separation element 22 of the fourth separator 21D via the ninth pipe 49 and the third connecting pipe 63.

[0027] The separation element 22 of the fourth separator 21D separates carbon dioxide from the air output to the separation element 22 of the fourth separator 21D via the third connecting pipe 63. The air from which carbon dioxide has been separated by the separation element 22 of the fourth separator 21D is returned to the main pipe 20 via the third return pipe 33 and flows through the main pipe 20 toward the outlet 16b. On the other hand, the carbon dioxide separated from the air by the separation element 22, i.e., the air with a high proportion of carbon dioxide, is sucked by the suction pump 23 of the fourth separator 21D via the tenth pipe 50 and stored in the storage element 26 via the eleventh pipe 51.

[0028] In this way, the carbon dioxide capture system 10 separates and captures carbon dioxide from the air. The air flowing through the main pipe 20 toward the outlet 16b is supplied to the pneumatic device 13 via the outlet 16b and the third supply pipe 19.

[0029] Effects of the embodiment The above embodiment can achieve the following effects: (1) The carbon dioxide capture device 15 is provided between the compressor 12 and the pneumatic equipment 13 in the supply line 11, which is an existing facility that supplies air from the compressor 12 to the pneumatic equipment 13. Therefore, carbon dioxide can be captured by the carbon dioxide capture device 15 using the air that is supplied to the pneumatic equipment 13 via the supply line 11. Therefore, it is possible to efficiently capture carbon dioxide while minimizing equipment costs as much as possible, without having to newly install large-scale facilities dedicated solely to capturing carbon dioxide.

[0030] (2) It is desirable that the air supplied to the pneumatic device 13 via the supply line 11 does not contain moisture and foreign matter. For this reason, the existing supply line 11 has the conditioning device 14. This makes it possible to separate and recover carbon dioxide from the air after moisture and foreign matter have been removed by the conditioning device 14, which is an existing configuration. Therefore, carbon dioxide that does not contain moisture and foreign matter can be recovered efficiently.

[0031] (3) Carbon dioxide can be repeatedly separated from air by the multiple separation devices 21. Therefore, highly concentrated carbon dioxide can be recovered. The highly concentrated carbon dioxide can be stored in the storage element 26 of the separation device 21 located furthest downstream among the multiple separation devices 21.

[0032] (4) The storage element 26 is configured to be detachable from the eleventh pipe 51, which is a connecting pipe that connects the suction pump 23 and the storage element 26 to each other. This allows the storage element 26, in which highly concentrated carbon dioxide is stored, to be moved by removing the storage element 26 from the eleventh pipe 51. Therefore, the highly concentrated carbon dioxide stored in the storage element 26 can be easily utilized in various fields.

[0033] (5) The carbon dioxide capture device 15 separates carbon dioxide from air using a membrane separation method, which allows carbon dioxide to be separated from air with less energy than, for example, a chemical absorption method or a physical absorption method, which involves adsorbing carbon dioxide onto an adsorbent and then applying thermal energy to the adsorbent to separate the carbon dioxide from the adsorbent.

[0034] [Modifications] The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0035] In the embodiment, there is no particular limitation on the number of separation devices 21. In the embodiment, the storage element 26 may be configured to be undetachable from the eleventh pipe 51.

[0036] In the embodiment, the separation element 22 may separate carbon dioxide from air by zeolite separation, or may separate carbon dioxide from air by electrical separation. In short, the carbon dioxide capture device 15 may separate carbon dioxide from air by any of membrane separation, zeolite separation, or electrical separation. This method allows carbon dioxide to be separated from air with less energy than, for example, chemical absorption or physical absorption, which involves adsorbing carbon dioxide onto an adsorbent and then applying thermal energy to the adsorbent to separate the carbon dioxide from the adsorbent.

[0037] In an embodiment, the separation element 22 may separate carbon dioxide from air by a method such as chemical absorption or physical absorption, in which carbon dioxide is adsorbed onto an adsorbent material and then thermal energy is applied to the adsorbent material to strip the carbon dioxide from the adsorbent material.

[0038] In the embodiment, the storage element 26 may be, for example, an adsorbent. In short, the storage element 26 may have a configuration that allows it to store the carbon dioxide sucked by the suction pump 23 in the fourth separation device 21D.

[0039] In the embodiment, the conditioning device 14 may be configured to remove at least one of moisture and foreign matter. In the embodiment, the supply line 11 does not have to have the conditioning device 14.

Claims

1. A carbon dioxide capture system comprising: a supply line configured to supply air compressed by a compressor to a pneumatic device; and a carbon dioxide capture device configured to separate and capture carbon dioxide from the air compressed by the compressor, the carbon dioxide capture device being provided in the supply line between the compressor and the pneumatic device.

2. A carbon dioxide capture system as described in claim 1, wherein the supply line has a purification device configured to remove at least one of moisture and foreign matter contained in the air compressed by the compressor, and the carbon dioxide capture device is provided in the supply line between the purification device and the pneumatic device.

3. The carbon dioxide capture system according to claim 1 or claim 2, wherein the carbon dioxide capture apparatus has a plurality of separation devices configured to separate carbon dioxide from air, the plurality of separation devices being connected in series, each separation device having a separation element configured to separate carbon dioxide from the air, and a suction pump configured to suck in the carbon dioxide separated from the air by the separation element, and among the plurality of separation devices, a separation device that is not located at the most downstream has a tank configured to store the carbon dioxide sucked in by the suction pump, and a pressure regulating valve configured to maintain a constant pressure in the tank and output the carbon dioxide in the tank to the separation element of the separation device immediately downstream, and the carbon dioxide capture system according to claim 1 or claim 2, wherein the plurality of separation devices has a storage element configured to store the carbon dioxide sucked in by the suction pump.

4. A carbon dioxide capture system as described in claim 3, wherein the storage element is configured to be detachable from a connecting pipe that connects the suction pump and the storage element to each other.

5. A carbon dioxide capture system as described in any one of claims 1 to 4, wherein the carbon dioxide capture device is configured to separate carbon dioxide from the air by any one of membrane separation, zeolite separation, or electrical separation.

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