Carbon dioxide recovery device

Abstract

To provide a carbon dioxide recovery device having a more preferable structure for energy saving.SOLUTION: A carbon dioxide recovery device 1 according to the invention includes: an absorbent tank 10; a regenerator 20; and a liquid feeding pump 30 which suctions the absorbent from a bottom area of the absorbent tank 10 to send the absorbent to the regenerator 20. The regenerator 20 has: a pipeline 21 which is formed including a first guide part 21a for receiving the absorbent from the liquid feeding pump 30 and guiding the absorbent downward; a second guide part 21b for guiding the absorbent upward from an end of the first guide part 21a; and a third guide part 21c for guiding the absorbent downward from an end of the second guide part 21b; a heater 22 for heating solid deposits in the absorbent at the second guide part 21b; and a carbon dioxide exhaust port 23 formed at an upper end of the second guide part 21b.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to carbon dioxide capture devices. [Background technology]

[0002] Various methods have been proposed to capture carbon dioxide from exhaust gases and the atmosphere. One of the carbon dioxide capture methods, the chemical absorption method, is characterized by its high selectivity. In the chemical absorption method, carbon dioxide is captured as highly concentrated carbon dioxide by utilizing the property of a carbon dioxide absorption solution (hereinafter simply referred to as "absorption solution") that reacts with carbon dioxide at low temperatures and releases carbon dioxide at high temperatures.

[0003] A typical example of this type of carbon dioxide capture device is a two-tower type composed of an absorption tower and a regeneration tower. A two-tower type carbon dioxide capture device is typically configured such that carbon dioxide in the exhaust gas is absorbed by an absorption liquid in the absorption tower, the carbon dioxide is released from the absorption liquid that has absorbed the carbon dioxide in the regeneration tower, and the absorption liquid is circulated between the two towers (see, for example, Patent Document 1).

[0004] Conventionally, this type of carbon dioxide capture device has used monoethanolamine (MEA) or the like as an absorbing liquid, which needs to be heated to about 120°C when re-releasing carbon dioxide in a regeneration tower. Furthermore, typical absorbing liquids such as MEA typically absorb and release carbon dioxide in a liquid state (i.e., unlike isophoronediamine, which will be described later, MEA does not stabilize carbon dioxide as a solid precipitate even when reacting with carbon dioxide). Therefore, when circulating the absorbing liquid between the two, it is necessary to pump a large amount of the absorbing liquid and perform heat exchange during this process, thereby significantly adjusting the temperature of the absorbing liquid.

[0005] Therefore, in the carbon dioxide capture device according to the prior art, the absorption tower and the regeneration tower are of similar size, and the equipment is large. In addition, there is also the problem that the amount of energy required for the entire system is large because energy is also required to pump the absorption liquid. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-147171 [Non-patent literature]

[0007] [Non-Patent Document 1] Soichi Kikkawa, et al. "Direct Air Capture of CO2 Using a Liquid Amine-Solid Carbamic Acid Phase-Separation System Using Diamines Bearing an Aminocyclohexyl Group", ACS Environmental Au, August 2022,vol 2, pp354-pp362, Publication Date(Web):May 10, 2022,("URL: https: / / pubs.acs.org / doi / epdf / 10.1021 / acsenvironau.1c00065.pdf") Summary of the Invention [Problem to be solved by the invention]

[0008] In recent years, attention has been drawn to absorbents such as isophoronediamine, which precipitate as a solid upon reaction with carbon dioxide (see, for example, Non-Patent Document 1). Isophoronediamine is a type of diamine compound having a cyclohexylamine group.

[0009] Generally, when an amine reacts with carbon dioxide, an unstable carbamic acid is formed. However, when a diamine compound containing a cyclohexylamine group reacts with carbon dioxide, it forms a solid carbamic acid, which precipitates as a solid. Isophoronediamine exhibits this characteristic prominently. This solid precipitate, a type of carbamic acid (hereinafter simply referred to as "solid precipitate"), can be selectively extracted from the absorption solution by phase separation. Furthermore, at temperatures as low as about 60°C, this solid precipitate re-releases the absorbed carbon dioxide and returns to the original isophoronediamine. In other words, by using isophoronediamine as the absorption solution in a carbon dioxide capture device, it is possible to easily absorb and fix carbon dioxide, and also to reduce the size of the carbon dioxide capture device.

[0010] However, in the current carbon dioxide recovery apparatus, a suitable apparatus configuration using a diamine compound having a cyclohexylamine group, such as isophoronediamine, has not yet been fully investigated.

[0011] In particular, in this type of carbon dioxide capture device, energy saving of the device is important from the viewpoint of carbon neutrality, but from this viewpoint, there is room for improvement in current carbon dioxide capture devices.

[0012] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a carbon dioxide capture device having a more suitable configuration from the viewpoint of energy saving. [Means for solving the problem]

[0013] The present disclosure mainly solves the above-mentioned problems by: A carbon dioxide recovery device that uses a diamine compound having a cyclohexylamine group as an absorption liquid, an absorption liquid tank for storing the absorption liquid, introducing a gas to be separated containing carbon dioxide from the outside and bringing the gas into contact with the absorption liquid, thereby causing the carbon dioxide to be absorbed into the absorption liquid; a regenerator disposed between the regenerator and the absorption liquid tank so that the absorption liquid flows back; a liquid transfer pump that pumps up the absorption liquid from a bottom region of the absorption liquid tank and delivers it to the regenerator; Equipped with The regenerator comprises: a pipe including: a first guide section that receives the absorption liquid from a discharge port of the liquid feed pump and guides the absorption liquid downward from the discharge port; a second guide section that guides the absorption liquid upward from a terminal end of the first guide section; and a third guide section that guides the absorption liquid downward from a terminal end of the second guide section; a heater in the second guide section that directly or indirectly heats the solid precipitate in the absorption liquid; a carbon dioxide exhaust port formed at an upper end of the second guide portion and configured to exhaust the carbon dioxide emitted from the solid deposit to the outside; It is a carbon dioxide capture device having the above. [Effects of the Invention]

[0014] The carbon dioxide capture device according to the present disclosure is suitable from the viewpoint of energy conservation. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a diagram showing an example of the overall configuration of a carbon dioxide capture device according to an embodiment of the present invention. [Figure 2] An enlarged view of the piping of a carbon dioxide capture device according to one embodiment of the present invention. [Figure 3] FIG. 10 is a diagram showing the configuration of a carbon dioxide capture device according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0017] In the following, the terms "below" and "above" are used, and "below" and "above" mean "vertically below" and "vertically above", respectively.

[0018] <Configuration of Carbon Dioxide Capture Device 1> A carbon dioxide recovery apparatus according to one embodiment of the present invention (hereinafter referred to as "carbon dioxide recovery apparatus 1") will be described below.

[0019] Fig. 1 is a diagram showing an example of the overall configuration of the carbon dioxide capture device 1. Fig. 2 is an enlarged view of the piping 21 of the carbon dioxide capture device 1 (regenerator 20).

[0020] The carbon dioxide capture device 1 includes an absorption liquid tank 10 that stores an absorption liquid, a regenerator 20 that strips carbon dioxide from the absorption liquid, and a liquid feed pump 30 that sucks up the absorption liquid from the bottom region of the absorption liquid tank 10 and sends it to the regenerator 20. The absorption liquid regenerated in the regenerator 20 is returned to the absorption liquid tank 10 via a pipe 21.

[0021] The carbon dioxide recovery device 1 according to this embodiment is a device that recovers carbon dioxide directly from the atmosphere.

[0022] In the carbon dioxide recovery device 1 according to this embodiment, the above-mentioned isophorone diamine is used as the absorbing liquid, and specifically, the absorbing liquid according to this embodiment is made of a mixed liquid of isophorone diamine and water.

[0023] The solid precipitate of isophoronediamine (i.e., solid carbamic acid) is generated in the form of particles in the absorption liquid, but has the characteristic that the particles tend to aggregate together due to physical adsorptive forces such as van der Waals forces. Therefore, if the concentration of isophoronediamine in the absorption liquid is excessively high, a large amount of highly viscous solid precipitate in an aggregated state may accumulate at the bottom of the absorption liquid tank 10, making it difficult to deliver the liquid using the liquid delivery pump 30. From this perspective, the absorption liquid is preferably a mixed liquid in which isophoronediamine is diluted to 1% to 30% with a solvent such as water.

[0024] The absorption liquid tank 10 functions as an absorption tower, stores unreacted absorption liquid, and is disposed in a substantially sealed state. The absorption liquid tank 10 has a gas inlet 11 at the bottom of the tank, through which a gas to be separated (here, the atmosphere) containing carbon dioxide is introduced from the outside. The gas to be separated introduced from the gas inlet 11 comes into contact with the absorption liquid in the absorption liquid tank 10 as it rises within the absorption liquid tank 10. As a result, carbon dioxide from the gas to be separated is selectively absorbed by the absorption liquid. The absorption liquid that has absorbed the carbon dioxide then becomes a solid precipitate and settles to the bottom of the tank (precipitate accumulation region 10a).

[0025] A partition plate 13 is disposed at the bottom of the absorption liquid tank 10. An area intended for depositing solid deposits (hereinafter referred to as "deposit deposition area 10a") is formed on one side of the tank bottom, and an area intended for not depositing solid deposits (hereinafter referred to as "deposit non-deposit area 10b") is formed on the other side of the tank bottom. An intake port of a liquid feed pump 30 is disposed in the deposit deposition area 10a, and a gas inlet port 11 is disposed in the deposit non-deposit area 10b.

[0026] The partition plate 13 is formed so that the area it occupies in the deposit accumulation region 10a in a plan view narrows from top to bottom. That is, the carbon dioxide in the gas to be separated introduced from the gas inlet 11 comes into contact with the absorption liquid in the absorption liquid tank 10 and becomes a solid deposit as it rises from the deposit non-accumulation region 10b inside the absorption liquid tank 10. Then, this solid deposit sinks under its own weight, is guided by the partition plate 13, and is deposited on the deposit accumulation region 10a side.

[0027] A gas exhaust port 12 for exhausting gas to the outside is disposed at the top of the absorption liquid tank 10. From the gas exhaust port 12, CO2-free gas after carbon dioxide has been absorbed from the gas to be separated (here, the atmosphere) is exhausted.

[0028] For example, the outside air is pumped by an air pump 11a and flows into the gas inlet 11 of the absorption liquid tank 10. A filter 11b is provided in the flow path connected to the gas inlet 11, so that impurities contained in the gas to be separated (here, the air) introduced into the absorption liquid tank 10 are removed.

[0029] The liquid feed pump 30 pumps the absorption liquid from the deposit accumulation region 10a of the absorption liquid tank 10 and delivers it to the pipe 21 of the regenerator 20. That is, the liquid feed pump 30 pumps the absorption liquid from the portion of the deposit accumulation region 10a of the absorption liquid tank 10 where the concentration of solid deposits accumulated therein is high. Therefore, the liquid feed pump 30 can efficiently deliver the solid deposits to the regenerator 20. Here, the liquid feed pump 30 is configured to pump the absorption liquid from the deposit accumulation region 10a of the absorption liquid tank 10 to a position above the liquid level in the absorption liquid tank 10.

[0030] Any type of liquid feed pump 30 may be used, but a mono pump, which is classified as a rotary positive displacement uniaxial eccentric screw pump, is particularly suitable. With this configuration, it is possible to more easily suck up the solid precipitate together with the absorption liquid from the precipitate accumulation region 10a of the absorption liquid tank 10.

[0031] Here, the liquid feed pump 30 is arranged to be continuously driven, for example, to create a state in which the absorption liquid flows continuously through the pipe 21 of the regenerator 20. The driving force (feed rate) of the liquid feed pump 30 is maintained at a level that pushes the solid precipitate up to the top of the second guide portion 21b of the pipe 21 but does not creep up to the third guide portion 21c of the pipe 21, taking into consideration the settling speed of the solid precipitate in the S-shaped pipe 21.

[0032] The regenerator 20 includes a pipe 21, a heater 22, and a carbon dioxide exhaust port 23.

[0033] The piping 21 forms, for example, a substantially S-shaped flow path and is configured to aggregate solid precipitates from the absorbing liquid in one location during the process of guiding the absorbing liquid through the flow path. The piping 21 includes a first guide section 21a that receives the absorbing liquid from the discharge port 30a of the liquid feed pump 30 and guides the absorbing liquid downward from the discharge port 30a, a second guide section 21b that guides the absorbing liquid upward from the end of the first guide section 21a, and a third guide section 21c that guides the absorbing liquid downward from the end of the second guide section 21b and then returns it to the absorbing liquid tank 10. That is, the piping 21 guides the absorbing liquid downward, upward, and downward in an S-shaped manner, and then returns it to the absorbing liquid tank 10.

[0034] Here, the piping 21 is arranged so that the upper end of the second guide portion 21b is located above the liquid level of the absorbing liquid in the absorption liquid tank 10. Therefore, the upper end of the second guide portion 21b is exposed from the liquid level of the absorbing liquid. In other words, a carbon dioxide retention space is formed in the connection area between the second guide portion 21b and the third guide portion 21c. The carbon dioxide retention space is a space where carbon dioxide released in the second guide portion 21b of the piping 21 temporarily remains. This carbon dioxide retention space is formed to prevent the carbon dioxide released in the second guide portion 21b from being re-absorbed by the absorbing liquid.

[0035] The liquid level of the absorption liquid in the third guide section 21c is at the same height as the liquid level of the absorption liquid in the absorption liquid tank 10. This is because the liquid levels of the absorption liquid in the third guide section 21c and the absorption liquid in the absorption liquid tank 10 are both determined by atmospheric pressure.

[0036] On the other hand, the liquid level of the absorbing liquid in the second guide portion 21b reaches the connecting position between the second guide portion 21b and the third guide portion 21c at a position higher than the liquid level of the absorbing liquid in the third guide portion 21c. This is because the liquid level of the absorbing liquid in the second guide portion 21b is determined by the absorbing liquid continuously supplied from the liquid feed pump 30. In other words, by operating the liquid feed pump 30, the absorbing liquid at the top of the second guide portion 21b continuously flows out toward the third guide portion 21c. In other words, the absorbing liquid does not flow from the second guide portion 21b side to the third guide portion 21c side until it receives the driving force of the liquid feed pump 30.

[0037] In addition, the absorption liquid flowing through the third guide portion 21c is returned to the deposit non-accumulation region 10b in the absorption liquid tank 10.

[0038] In the pipe 21, solid precipitates in the absorption liquid settle to the bottom of the first guide section 21a of the pipe 21 due to their own weight. However, at this time, the solid precipitates are subjected to the flow of absorption liquid in the pipe 21 generated by the liquid feed pump 30, so the solid precipitates rise to a height where the flow rate and the settling speed are balanced, and are pushed up to the top of the second guide section 21b of the pipe 21. Note that at this time, the driving force (feed rate) of the liquid feed pump 30 is maintained at a level that prevents the solid precipitates from creeping up to the third guide section 21c side, as described above. Therefore, the solid precipitates delivered from the absorption liquid tank 10 are in an agglomerated state at the top of the second guide section 21b of the pipe 21.

[0039] The heater 22 heats the second guide portion 21b of the pipe 21 or the solid precipitates present in the second guide portion 21b. As described above, the solid precipitates are in an agglomerated state in the upper portion of the second guide portion 21b of the pipe 21. That is, the heater 22 is capable of intensively heating the agglomerated solid precipitates.

[0040] The type of heater 22 may be any type as long as it can heat the solid precipitates present in the second guide portion 21b, but from the viewpoint of energy conservation, a heat exchanger that uses hot water is particularly preferable. Generally, hot water (e.g., water used for cooling) is constantly discharged from a power machine, and by using this hot water as the heater 22, it is possible to achieve effective use of energy. Furthermore, it is preferable that the heater 22 is configured, for example, to be wound around the outer periphery of the second guide portion 21b of the pipe 21. This can prevent the flow of solid precipitates in the pipe 21 from being obstructed or prevent breakdowns in the pipe 21 due to the adhesion of solid precipitates.

[0041] The solid precipitate of isophoronediamine re-releases the absorbed carbon dioxide at about 60° C. and returns to the original isophoronediamine. Therefore, even when the absorption liquid is flowing through the pipe 21, the heater 22 can sufficiently raise the temperature to a level at which the solid precipitate returns to the original isophoronediamine.

[0042] The heater 22 is preferably configured to heat the solid precipitate so that its temperature rises to about 80° C. This makes it possible to increase the rate at which carbon dioxide is re-released from the solid precipitate to a certain degree, while suppressing the evaporation of water in the absorption liquid.

[0043] The carbon dioxide exhaust port 23 is formed at the upper end of the second guide portion 21b of the pipe 21, and exhausts to the outside the carbon dioxide separated from the absorbing solution in the second guide portion 21b (i.e., the carbon dioxide released by the solid precipitate). Because the carbon dioxide separated from the absorbing solution in the second guide portion 21b does not return to the first guide portion 21a side or the third guide portion 21c side due to the presence of the absorbing solution, all of the carbon dioxide moves to the carbon dioxide retention space above the second guide portion 21b and heads toward the carbon dioxide exhaust port 23.

[0044] In addition, in the carbon dioxide recovery device 1 according to this embodiment, the absorbing solution is heated in the piping 21, and the solid precipitate in the absorbing solution is returned to the original isophoronediamine. Therefore, the regenerator 20 does not require a tank for regenerating the absorbing solution.

[0045] Furthermore, in the carbon dioxide recovery device 1 according to this embodiment, when carbon dioxide is released from the solid precipitate, the entire absorption liquid is not heated to a high temperature, and therefore there is no need to provide a cooling device for cooling the absorption liquid in the path returning the absorption liquid from the regenerator 20 to the absorption liquid tank 10.

[0046] <Operation of Carbon Dioxide Capture Device 1> Next, an example of the operation of separating and capturing carbon dioxide in the carbon dioxide capture device 1 will be described.

[0047] When the carbon dioxide capture device 1 is operated, first, external gas to be separated (here, atmospheric air) is pumped by an air pump 11a and flows into the gas inlet 11 of the absorption liquid tank 10. The gas to be separated introduced from the gas inlet 11 comes into contact with the absorbing liquid in the absorption liquid tank 10 as it rises inside the absorption liquid tank 10. As a result, carbon dioxide from the gas to be separated is selectively absorbed by the absorbing liquid. Then, the absorbing liquid that has absorbed the carbon dioxide becomes a solid precipitate and settles and accumulates in a precipitate accumulation region 10a at the bottom of the absorption liquid tank 10.

[0048] The absorption liquid having a high concentration of solid precipitates deposited in the bottom region of the absorption liquid tank 10 is pumped up by the liquid feed pump 30 and sent to the pipe 21 of the regenerator 20. In the pipe 21, the solid precipitates in the absorption liquid settle to the bottom of the first guide section 21a of the pipe 21 due to their own weight. However, at this time, the solid precipitates are subjected to the flow of the absorption liquid in the pipe 21 generated by the liquid feed pump 30, so that the solid precipitates rise to a height where the flow speed and the settling speed are balanced, and are pushed up to the top of the second guide section 21b of the pipe 21. Then, the absorption liquid is continuously supplied from the liquid feed pump 30 into the pipe 21, and the absorption liquid is continuously flowing through the pipe 21. Therefore, a region where the solid precipitates are aggregated is formed in the top of the second guide section 21b.

[0049] The solid precipitate that has become coagulated in the second guide portion 21b of the pipe 21 is heated by the heater 22. The gaseous carbon dioxide that has been desorbed from the absorbing liquid (i.e., the solid precipitate) by heating flows upward and is exhausted from the carbon dioxide exhaust port 23 of the regenerator 20. Meanwhile, the solid precipitate from which carbon dioxide has been desorbed returns to liquid isophoronediamine, mixes with the absorbing liquid that has been sent as isophoronediamine (i.e., the absorbing liquid that has not become a solid precipitate), and flows toward the third guide portion 21c of the pipe 21. The absorbing liquid that has flowed toward the third guide portion 21c of the pipe 21 is then returned to the absorbing liquid tank 10.

[0050] The carbon dioxide recovery device 1 continuously performs the above-described operations to separate and recover carbon dioxide from the gas to be separated (here, the atmosphere).

[0051] <Effects> As described above, the carbon dioxide recovery device 1 according to this embodiment has the following features: an absorption liquid tank (10) for storing an absorption liquid, introducing a gas to be separated containing carbon dioxide from the outside and bringing the gas into contact with the absorption liquid to absorb the carbon dioxide; a regenerator (20) disposed between the regenerator (20) and the absorption liquid tank (10) so that the absorption liquid flows back; a liquid pump 30 that sucks up the absorption liquid from the bottom region of the absorption liquid tank 10 and sends it to the regenerator 20; Equipped with The regenerator 20 is a pipe (21) including a first guide section (21a) that receives the absorbing liquid from a discharge port (30a) of the liquid feed pump (30) and guides the absorbing liquid downward from the discharge port (30a), a second guide section (21b) that guides the absorbing liquid upward from a terminal end of the first guide section (21a), and a third guide section (21c) that guides the absorbing liquid downward from a terminal end of the second guide section (21b); a heater 22 for directly or indirectly heating the solid precipitate in the absorption liquid in the second guide portion 21b; a carbon dioxide exhaust port 23 formed at the upper end of the second guide portion 21b, for exhausting carbon dioxide emitted from the solid deposit to the outside; It has.

[0052] According to the carbon dioxide recovery device 1 of this embodiment, the solid precipitates that have been precipitated in the absorbing solution (here, isophoronediamine) due to the absorption of carbon dioxide are collected in one place, and the solid precipitates can be heated in a concentrated manner while being aggregated as much as possible. This makes it possible to separate and recover carbon dioxide from the absorbing solution with less energy.

[0053] Furthermore, according to the carbon dioxide capture device 1 of this embodiment, there is no need to provide a tank for storing the absorption liquid to be regenerated in the regenerator 20, and there is no need to provide a cooling device for cooling the absorption liquid in the path that returns the absorption liquid from the regenerator 20 to the absorption liquid tank 10. This makes it possible to reduce the size of the entire device compared to carbon dioxide capture devices according to conventional techniques.

[0054] <Modification> FIG. 3 is a diagram showing an example of the configuration of the carbon dioxide capture device 1 according to a modified example.

[0055] The carbon dioxide capture device 1 according to the modified example differs from the carbon dioxide capture device 1 according to the above embodiment in that a capture material 25 is provided in the second guide portion 21b of the pipe 21 of the regenerator 20.

[0056] The trapping material 25 traps solid precipitates from the absorption liquid passing through the second guide part 21b. The trapping material 25 is, for example, a mesh, stainless steel wool, or glass wool, and is arranged so as to block the flow path of the second guide part 21b. More specifically, the trapping material 25 is arranged above the second guide part 21b.

[0057] As described above, the absorption liquid is continuously supplied from the liquid feed pump 30 into the pipe 21, and the absorption liquid flows continuously. At this time, the adsorption material 25 prevents the solid precipitate from being affected by the flow of the absorption liquid and flowing from the second guide portion 21b to the third guide portion 21c. In other words, by providing the adsorption material 25, it is possible to more reliably cause the solid precipitate to aggregate above the second guide portion 21b.

[0058] The solid precipitate that has been captured by the capturing material 25 and is in an agglomerated state is heated by the heater 22, as in the carbon dioxide capture device 1 according to the above embodiment. Then, the gaseous carbon dioxide that has been desorbed from the absorbing liquid (i.e., the solid precipitate) by heating flows upward and is exhausted from the carbon dioxide exhaust port 23 of the regenerator 20.

[0059] As described above, the carbon dioxide capture device 1 according to this modification can more effectively collect the solid precipitate in one place and heat the solid precipitate in a concentrated manner while it is in a state where it is aggregated as much as possible. This makes it possible to separate and capture carbon dioxide from the absorption liquid with less energy.

[0060] Although specific examples of the present invention have been described above in detail, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and alterations of the specific examples exemplified above.

[0061] (Other embodiments) The present invention is not limited to the above-described embodiment, and various modifications are possible.

[0062] For example, in the above embodiment, a heat exchanger using hot water is shown as an example of the heater 22. However, the heater 22 may also be a sheath heater, a microwave heating device, or the like.

[0063] Furthermore, in the above embodiment, a mode in which carbon dioxide is directly captured from the atmosphere has been shown as an example of the carbon dioxide capture device 1. However, the carbon dioxide capture device 1 may also be applied as a device that captures carbon dioxide from the exhaust gas of an engine. [Industrial Applicability]

[0064] The carbon dioxide capture device according to the present disclosure is suitable from the viewpoint of energy conservation. [Explanation of symbols]

[0065] 1. Carbon dioxide capture device 10 Absorbent tank 10a Precipitate deposition area 10b Precipitate non-deposition area 11 Gas inlet 11a Air pump 11b filter 12 Gas exhaust port 13 Divider 20 Regenerator 21 Piping 21a 1st information section 21b 2nd information section 21c 3rd Information Department 22 Heater 23 Carbon dioxide exhaust vent 25 Collection material 30 Liquid transfer pump 30a outlet

Claims

1. A carbon dioxide recovery device that uses a diamine compound having a cyclohexylamine group as an absorption liquid, an absorption liquid tank for storing the absorption liquid, introducing a gas to be separated containing carbon dioxide from the outside and bringing the gas into contact with the absorption liquid, thereby causing the carbon dioxide to be absorbed into the absorption liquid; a regenerator disposed between the regenerator and the absorption liquid tank so that the absorption liquid flows back; a liquid transfer pump that pumps up the absorption liquid from a bottom region of the absorption liquid tank and delivers it to the regenerator; Equipped with The regenerator comprises: a pipe including: a first guide section that receives the absorption liquid from a discharge port of the liquid feed pump and guides the absorption liquid downward from the discharge port; a second guide section that guides the absorption liquid upward from a terminal end of the first guide section; and a third guide section that guides the absorption liquid downward from a terminal end of the second guide section; a heater in the second guide portion that directly or indirectly heats the solid precipitate in the absorption liquid; a carbon dioxide exhaust port formed at an upper end of the second guide portion, for exhausting the carbon dioxide emitted from the solid deposit to the outside; A carbon dioxide capture device having:

2. The regenerator is disposed in the second guide section and has a collection material that collects the solid precipitate from the absorption liquid passing through the second guide section. The carbon dioxide capture device according to claim 1 .

3. The liquid feed pump is continuously driven so that the solid precipitate aggregates at a predetermined position in the second guide portion. The carbon dioxide capture device according to claim 1 .

4. The liquid level of the absorption liquid in the absorption liquid tank is located below the connection position between the second guide portion and the third guide portion of the piping. The carbon dioxide capture device according to claim 1 .

5. The heater heats the solid deposit from outside the second guide portion of the pipe. The carbon dioxide capture device according to claim 1 .

6. The heater is composed of a heat exchanger that uses hot water. The carbon dioxide capture device according to claim 1 .

7. The piping has a substantially S-shape due to the first guide portion, the second guide portion, and the third guide portion. The carbon dioxide capture device according to claim 1 .

8. The diamine compound is isophoronediamine. The carbon dioxide capture device according to claim 1 .

9. a partition plate is disposed at the bottom of the absorption liquid tank, and a first region in which the solid precipitate is deposited is formed on one side of the partition plate at the bottom, and a second region in which the solid precipitate is not deposited is formed on the other side of the partition plate at the bottom, an intake port of the liquid feed pump is disposed in the first region; A gas inlet for the gas to be separated is provided in the second region. The carbon dioxide capture device according to claim 1 .

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