Carbon dioxide recovery device and carbon dioxide recovery method

Abstract

This carbon dioxide recovery device is provided with: a first adsorption chamber having an intake port and an exhaust port that open to the atmosphere; a fan; the air door can close the first adsorption chamber; a first adsorption unit capable of adsorbing carbon dioxide; the second adsorption chamber and the first adsorption chamber are arranged together; a connection pipe that connects the first adsorption chamber and the second adsorption chamber; a second adsorption unit that is disposed in the second adsorption chamber and is capable of adsorbing carbon dioxide; an on-off valve provided to the connection pipe; a first desorption unit that desorbs the carbon dioxide absorbed by the first adsorption unit; a second desorption unit that desorbs the carbon dioxide absorbed by the second adsorption unit; and a suction unit connected to the second adsorption unit and capable of sucking gas in the first adsorption chamber and the second adsorption chamber.

Description

Technical Field

[0001] The present disclosure relates to a carbon dioxide recovery device and a carbon dioxide recovery method.

[0002] This application claims priority to Japanese Patent Application No. 2022-139430 filed in Japan on September 1, 2022, the contents of which are incorporated herein by reference. Background Art

[0003] In recent years, from the perspective of carbon neutrality, the concentration of carbon dioxide contained in the atmosphere has attracted attention. As an example of a measure for reducing the concentration of carbon dioxide, a technology called DAC (Direct Air Capture) has been proposed so far. In this technology, the following method is adopted: after the carbon dioxide contained in the atmosphere guided to the adsorption chamber is adsorbed by an adsorbent, the adsorption chamber is depressurized or heated, thereby attracting and storing the carbon dioxide detached from the adsorbent outside, or efficiently utilizing it (for example, refer to the following patent document 1 and the following patent document 2). In addition, as an example of a technology for adsorbing gas using an adsorbent, a method for treating rare gases in nuclear power plants shown in the following patent document 3 is known.

[0004] Here, when the pressure of the adsorption chamber is reduced when carbon dioxide is released, in order to ensure the airtightness of the adsorption chamber, the inlet and outlet of the adsorption chamber need to be isolated by a damper with high sealing performance, etc. In addition, the adsorption chamber itself needs to be a high pressure-resistant structure.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent No. 6659717

[0008] Patent Document 2: Japanese Patent No. 6622302

[0009] Patent Document 3: Japanese Patent No. 6697535 Summary of the invention

[0010] Problems to be solved by the invention

[0011] However, preparing a damper with high sealing performance and an adsorption chamber with a high pressure-resistant structure as described above is disadvantageous in terms of manufacturing cost and maintenance cost. Therefore, there is an increasing demand for a more economical and efficient carbon dioxide recovery device.

[0012] The present disclosure has been made to solve the above-mentioned problems, and its object is to provide a more economical and efficient carbon dioxide recovery device and carbon dioxide recovery method.

[0013] Means for solving problems

[0014] In order to solve the above problems, the carbon dioxide recovery device of the present disclosure comprises:

[0015] A first adsorption chamber having an air intake port and an air exhaust port open to the atmosphere;

[0016] a fan for forming a flow of air in a direction from the air intake port toward the air exhaust port;

[0017] a damper capable of closing the exhaust port;

[0018] A first adsorption unit is disposed in the first adsorption chamber and is capable of adsorbing carbon dioxide contained in the air;

[0019] A second adsorption chamber, which is provided together with the first adsorption chamber;

[0020] a connecting pipe connecting the first adsorption chamber and the second adsorption chamber;

[0021] a second adsorption unit disposed in the second adsorption chamber and capable of adsorbing carbon dioxide contained in the gas flowing in from the connecting pipe;

[0022] an on-off valve, which is arranged on the connecting pipe;

[0023] a first desorption unit for desorption of carbon dioxide absorbed by the first adsorption unit;

[0024] a second desorption section that desorbs the carbon dioxide absorbed by the second adsorption section; and

[0025] The suction unit is connected to the second adsorption unit and is capable of sucking the gas in the first adsorption chamber and the second adsorption chamber.

[0026] The carbon dioxide recovery method disclosed in the present invention is a carbon dioxide recovery method using the above-mentioned carbon dioxide recovery device, wherein:

[0027] The carbon dioxide recovery method comprises the following steps:

[0028] In a state where the on-off valve is closed, the damper is opened and the fan is driven, thereby allowing carbon dioxide to be adsorbed on the first adsorption portion;

[0029] In a state where the damper is closed and the on-off valve is opened, the first separation portion is driven to separate the carbon dioxide adsorbed on the first adsorption portion, and the gas containing the separated carbon dioxide is guided to the second adsorption chamber through the connecting pipe by driving the suction portion, so that the carbon dioxide is adsorbed on the second adsorption portion; and

[0030] In a state where the on-off valve is closed, the suction unit and the second separation unit are driven to separate the carbon dioxide adsorbed on the second adsorption unit and guide it to the outside.

[0031] The step of allowing the first adsorption unit to adsorb carbon dioxide and the step of desorbing the carbon dioxide adsorbed on the second adsorption unit and introducing the carbon dioxide to the outside are performed in parallel.

[0032] Effects of the Invention

[0033] According to the present disclosure, a more economical and efficient carbon dioxide recovery device and carbon dioxide recovery method are provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram showing the structure of the carbon dioxide recovery device according to the embodiment of the present disclosure.

[0035] Figure 2 1 is a flow chart showing each step of a carbon dioxide recovery method according to an embodiment of the present disclosure.

[0036] Figure 3 This is an explanatory diagram showing a state of one step in the carbon dioxide recovery method according to the embodiment of the present disclosure.

[0037] Figure 4 It is an explanatory diagram showing the state of other steps in the carbon dioxide recovery method according to the embodiment of the present disclosure.

[0038] Figure 5 It is a schematic diagram showing a modified example of the carbon dioxide recovery device according to the embodiment of the present disclosure.

[0039] Figure 6 It is a schematic diagram showing a modified example of the first adsorption chamber according to the embodiment of the present disclosure. DETAILED DESCRIPTION

[0040] Below, refer to Figures 1 to 4 The carbon dioxide recovery device 1 and the carbon dioxide recovery method according to the embodiment of the present disclosure will be described.

[0041] (Structure of carbon dioxide recovery device)

[0042] The carbon dioxide recovery device 1 of this embodiment is a device for directly adsorbing and recovering carbon dioxide contained in the atmosphere. Figure 1As shown, the carbon dioxide recovery device 1 includes a first adsorption chamber 10, a first adsorption part 11, a fan 12, a damper 13, a second adsorption chamber 20, a second adsorption part 21, a connecting pipe 30, an on-off valve 31, a first cooler 32, a first separation part 41, a second separation part 42, a suction part 50, a second cooler 61, a concentration measuring part 70, a recovery pipe 80, an atmosphere release pipe 81, a condensed water discharge pipe 82, a third on-off valve 93, and a fourth on-off valve 94.

[0043] The first adsorption chamber 10 has an air inlet 10a which is open to the atmosphere and can inhale air, and an exhaust port 10b which is arranged on the side opposite to the air inlet 10a. A fan 12 which forms an air flow in the direction from the air inlet 10a toward the exhaust port 10b is arranged at the exhaust port 10b. The fan 12 generates the above-mentioned air flow by being driven to rotate. It should be noted that in the following description, the direction in which the air flows is sometimes referred to as the "upstream side", and the opposite side thereof is referred to as the "downstream side".

[0044] A damper 13 capable of closing the exhaust port 10b is provided at the upstream side of the fan 12 in the exhaust port 10b. The damper 13 is plate-shaped and is supported to be rotatable around a rotation axis extending in a horizontal direction perpendicular to the paper surface. The damper 13 has a simple structure and suppresses the introduction of atmosphere that does not capture carbon dioxide from the exhaust port 10b into the connecting pipe 30 described later.

[0045] A first adsorption section 11 is arranged inside the first adsorption chamber 10. The first adsorption section 11 is formed of a substance that can physically or chemically capture and adsorb carbon dioxide contained in the air flowing in the first adsorption chamber 10. As the first adsorption section 11, since the ventilation volume increases by processing air in the atmosphere with a low concentration of carbon dioxide, a porous structure with low pressure loss and a large specific surface area is used. As an example, the first adsorption section 11 has a honeycomb structure having a plurality of holes that are open in the flow direction of the air. In other words, the pressure loss of the first adsorption section 11 to the flow of air is smaller than that of the second adsorption section 21 described later. It should be noted that, as the first adsorption section 11, in addition to the honeycomb structure, a lattice-shaped, fibrous, or other adsorption material may also be used.

[0046] A first detachment section 41 is provided in an area overlapping with the first adsorption section 11, on the inside or outside of the first adsorption chamber 10 and when viewed from a direction perpendicular to the flow direction of the gas in the first adsorption chamber 10. The first detachment section 41 is provided to detach the carbon dioxide adsorbed by the first adsorption section 11 and regenerate the first adsorption section 11. In the present embodiment, the first detachment section 41 is a first heating section 43. As an example, the first heating section 43 may be an electric heater, a heat exchanger for supplying a heating fluid, a microwave heating device, or the like. In other words, by operating the first heating section 43, the first adsorption section 11 is heated, the adsorbed carbon dioxide is detached and mixed with the gas flowing on the outside, and the first adsorption section 11 is regenerated.

[0047] A first concentration meter 71 as one of the concentration measuring units 70 is disposed at the air intake port 10a. A second concentration meter 72 as one of the concentration measuring units 70 is disposed at the air exhaust port 10b. The first concentration meter 71 and the second concentration meter 72 measure and digitize the concentration of carbon dioxide contained in the air, and send it to the outside as an electrical signal, which is used as a control signal of the carbon dioxide recovery device 1.

[0048] The second adsorption chamber 20 is another space provided together with the first adsorption chamber 10. The second adsorption chamber 20 is connected to the first adsorption chamber 10 through the connecting pipe 30. One end of the connecting pipe 30 opens in the area on the downstream side of the first adsorption section 11 in the first adsorption chamber 10. In other words, the gas that has passed through the first adsorption section 11 can flow into the connecting pipe 30. It should be noted that in the connecting pipe 30, the description of "upstream side" and "downstream side" is sometimes made based on the flow direction of the gas flowing from the first adsorption chamber 10 side to the second adsorption chamber 20 side.

[0049] Considering the specific gravity of carbon dioxide, it is preferred to set the opening of the connecting pipe 30 in the vertical downward direction in a manner that forms a smooth flow by self-weight. A second adsorption section 21 is provided inside the second adsorption chamber 20. The second adsorption section 21 is formed of a substance that can adsorb carbon dioxide contained in the gas, similarly to the first adsorption section 11. It should be noted that, for the sake of compactness, the porosity of the second adsorption section 21 may also be lower than the porosity of the first adsorption section 11 (in other words, the density of the second adsorption section 21 is higher than the density of the first adsorption section 11.), and the volume of the second adsorption section 21 may also be smaller than the volume of the first adsorption section 11. As an example, the second adsorption section 21 is an aggregate of a granular or honeycomb-shaped adsorption material having a higher density than the first adsorption chamber. As a result, in the second adsorption section 21, the amount of carbon dioxide recovered per unit volume is greater than that of the first adsorption section 11, so that the leakage of the gas component remaining in the ineffective space of the device can be reduced, and the purity of the recovered carbon dioxide can be improved.

[0050] A second detachment section 42 is provided on the inner side or the outer side of the second adsorption chamber 20. The second detachment section 42 has a second heating section 44 and a water vapor supply section 45. The second heating section 44 is similar to the first heating section 43. As an example, an electric heater, a heat exchanger for supplying a heating fluid, a microwave heating device, a porous body that generates heat by supplying an electric current, etc. can be considered. The second heating section 44 heats the second adsorption section 21 to detach the adsorbed carbon dioxide and regenerate the second adsorption section 21. The water vapor supply section 45 is provided for the purpose of promoting the detachment of carbon dioxide from the second adsorption section 21. The water vapor supply section 45 can supply water vapor to the connecting pipe 30 from the upstream side of the second adsorption section 21. It should be noted that a structure without a water vapor supply section 45 can also be adopted.

[0051] On the above-mentioned connecting pipe 30, the third concentration meter 73 (concentration measuring unit 70), the first opening and closing valve 91 (opening and closing valve 31), the first cooler 32, and the second opening and closing valve 92 (opening and closing valve 31) are arranged in order from the upstream side to the downstream side. The third concentration meter 73 measures and digitizes the carbon dioxide concentration in the gas flowing in the connecting pipe 30, and sends it to the outside as an electrical signal. The first opening and closing valve 91 and the second opening and closing valve 92 switch the communication state between the upstream side and the downstream side of the connecting pipe 30. In other words, by closing these opening and closing valves 31, the first adsorption chamber 10 and the second adsorption chamber 20 are isolated. The first cooler 32 is provided to cool the gas heated to a high temperature by the first heating unit 43 as the above-mentioned first separation unit 41. It should be noted that the first cooler 32 can also be omitted according to the nature, specification, and state of the second adsorption unit 21 arranged on the downstream side.

[0052] A recovery pipe 80 is connected to the downstream side of the second adsorption section 21. On the recovery pipe 80, a fourth concentration meter 74 as a concentration measuring section 70, a suction section 50, a third opening and closing valve 93, and a second cooler 61 are sequentially arranged from the upstream side to the downstream side. The fourth concentration meter 74 measures and digitizes the concentration of carbon dioxide in the gas after passing through the second adsorption section 21, and sends it to the outside as an electrical signal. The suction section 50 is a suction pump, and by making the recovery pipe 80 negative pressure, a flow of gas from the above-mentioned first adsorption chamber 10 to the recovery pipe 80 is formed.

[0053] A carbon dioxide storage device (not shown) is connected to the end of the downstream side of the recovery pipe 80. It should be noted that, in the present embodiment, an example of connection to a storage device is shown, but the connection destination of the recovery pipe 80 is not limited thereto, and it can also be connected to a carbon dioxide utilization device. The third opening and closing valve 93 is provided to switch the flow state of the gas to the storage device. The second cooler 61 is a heat exchanger for cooling and condensing the water vapor supplied by the above-mentioned water vapor supply unit 45. It should be noted that in the absence of the water vapor supply unit 45, the second cooler 61 is not required. The condensed water generated by the second cooler 61 is discharged to the outside through the condensed water discharge pipe 82. In addition, the atmospheric release pipe 81 branches between the suction unit 50 and the third opening and closing valve 93 in the recovery pipe 80. A fourth opening and closing valve 94 is provided in the middle of the atmospheric release pipe 81. The fourth opening and closing valve 94 switches the flow state of the gas in the atmospheric release pipe 81.

[0054] (Carbon dioxide recovery method)

[0055] Next, refer to Figures 2 to 4 A method for recovering carbon dioxide using the above-mentioned carbon dioxide recovery device 1 is described. Figure 2 As shown, the method includes: step S1 of using the first adsorption part 11 to adsorb carbon dioxide; step S2 of determining whether the first adsorption part 11 has completely adsorbed (permeated) carbon dioxide; step S3 of causing carbon dioxide to detach from the first adsorption part 11; step S31 of determining whether the detachment of the first adsorption part 11 is completed; step S4 of causing carbon dioxide to adsorb on the second adsorption part 21; step S41 of determining whether the second adsorption part 21 is permeated; step S5 of causing carbon dioxide to detach from the second adsorption part 21; step S6 of determining whether carbon dioxide is completely detached from the second adsorption part 21; and step S21 of determining whether any one of step S2 and step S6 is determined as "yes".

[0056] like Figure 3 As shown, in step S1, the on-off valve 31 is set to a closed state, and the damper 13 is set to an open state. The fan 12 is driven in this state. As a result, the air (atmosphere) flows into the first adsorption chamber 10 through the air intake port 10a. In the middle of flowing from the air intake port 10a toward the exhaust port 10b, the air contacts the first adsorption section 11. As a result, most of the carbon dioxide contained in the air is adsorbed by the first adsorption section 11. Next, in step S2, based on the output values ​​of the first concentration meter 71 and the second concentration meter 72, it is determined whether it has passed through the first adsorption section 11. In other words, when the carbon dioxide concentration shown by the first concentration meter 71 is equal to the carbon dioxide concentration shown by the second concentration meter 72, it means that the adsorption of carbon dioxide by the first adsorption section 11 does not proceed further, and therefore it is determined to have passed through the first adsorption section 11. It should be noted that in Figure 3 In the embodiment, the permeation state is determined based on the difference in carbon dioxide concentration entering and leaving the first adsorption unit 11. However, if the adsorption characteristics are known, the permeation state can also be determined by the adsorption time such as a timer. Figure 3 In the embodiment, whether or not the first adsorption unit 11 has been penetrated is determined based on the values ​​of the first and second concentration meters 71 and 72, but it is also possible to make a determination based on the value of the second concentration meter 72 only without the first concentration meter 71. In this case, it means that the adsorption of carbon dioxide does not proceed further at the moment when the value of the second concentration meter 72 indicates the concentration of carbon dioxide in the atmosphere, and therefore it is determined that the carbon dioxide has penetrated the first adsorption unit 11. In addition, it is also possible to consider the operating efficiency, and until the first adsorption unit 11 is completely penetrated, that is, until the value shown by the second concentration meter 72 is equal to the value shown by the first concentration meter 71, the difference between the two concentration meters is accumulated, and it is determined that the carbon dioxide has penetrated at the stage where a certain amount of adsorption is confirmed.

[0057] like Figure 2 As shown, steps S5 and S6 are performed in parallel with the above-mentioned steps S1 and S2. In other words, while the first adsorption unit 11 is adsorbing carbon dioxide in step S1, the adsorbed carbon dioxide is desorbed in the second adsorption unit 21 (step S5). The desorption is performed by energizing the second heating unit 44 or supplying a heating fluid to heat the second adsorption unit 21, and by supplying water vapor to the second adsorption unit 21 through the water vapor supply unit 45. By driving the suction unit 50 in this state, the gas containing the desorbed carbon dioxide is sent to a storage device (not shown) through the recovery pipe 80, and the carbon dioxide is recovered.

[0058] After step S5, in step S6, it is determined whether the desorption of carbon dioxide from the second adsorption unit 21 is completed. In this step S6, the cumulative amount of carbon dioxide desorbed is calculated based on the carbon dioxide concentration measured by the fourth concentration meter 74, and it is determined whether the desorption is completed based on the adsorption capacity of the second adsorption unit 21 obtained in advance. In other words, when the cumulative amount of carbon dioxide desorbed calculated based on the carbon dioxide concentration measured by the fourth concentration meter 74 is equal to the carbon dioxide adsorption capacity of the second adsorption unit 21 obtained in advance, it is impossible to foresee further desorption of carbon dioxide, so it is determined that the desorption is completed (step S6: yes). In the case of "no" in step S6, step S5 is executed again to perform further desorption. It should be noted that if the desorption characteristics of the second adsorption unit 21 are known, it is also possible to pre-set a period for predicting the completion of desorption by a timer or the like, and determine that the desorption is completed based on the passage of this period.

[0059] In step S21, it is determined whether the above step S2 and step S6 are both determined as "yes". If it is determined as "no" in step S21, the determination of step S21 is performed again. If it is determined as "yes" in step S21, the desorption of carbon dioxide from the first adsorption unit 11 in step S3 and the adsorption of carbon dioxide in the second adsorption unit 21 in step S4 are performed in parallel. Step S3 is achieved by supplying power or heating fluid to the above-mentioned first heating unit 43. Figure 4 As shown, at this time, the on-off valve 31 is in an open state. In addition, the damper 13 is also in a state of closing the exhaust port 10b. After step S3, it is determined in step S31 whether the detachment and regeneration of the first adsorption unit 11 are completed. This step S31 is performed by the same processing as the above-mentioned step S6. In the case of "no" in step S31, the detachment and regeneration of the first adsorption unit 11 are continued. In step S4, the gas containing carbon dioxide detached from the first adsorption unit 11 flows into the second adsorption chamber 20 on the downstream side through the connecting pipe 30. As a result, the carbon dioxide in the gas is adsorbed by the second adsorption unit 21. In other words, the carbon dioxide adsorbed by the first adsorption unit 11 is further adsorbed by the second adsorption unit 21. Next, in step S41, it is determined whether the second adsorption unit 21 is permeated. In step S41, the cumulative amount of carbon dioxide detached is calculated based on the carbon dioxide concentration measured by the fourth concentration meter 74, and it is determined whether the detachment is completed based on the adsorption capacity of the second adsorption unit 21 obtained in advance. If the determination result in step S41 is "No", step S4 is then executed to continue the adsorption of carbon dioxide by the second adsorption unit 21. If the determination result in either step S31 or step S41 is "Yes", the process returns to step S1 again. This is because if the adsorption in the first adsorption unit 11 is completed, the gas rich in carbon dioxide cannot be supplied to the second adsorption unit 21, which is disadvantageous from the viewpoint of ensuring efficiency.

[0060] The carbon dioxide recovery method of this embodiment is realized by continuously and repeatedly executing the above steps S1 to S6. It should be noted that in order to continuously perform the carbon dioxide adsorption process and desorption process, a pair of carbon dioxide recovery devices 1 that alternately perform their opposite operations may be configured in combination.

[0061] (Effect)

[0062] In recent years, from the perspective of carbon neutrality, the concentration of carbon dioxide contained in the atmosphere has attracted attention. As an example of a measure for reducing the concentration of carbon dioxide, a technology called DAC (Direct Air Capture) has been proposed so far. In this technology, the following method is adopted: after the carbon dioxide contained in the atmosphere guided to the adsorption chamber is adsorbed by an adsorbent, the adsorption chamber is depressurized or heated, thereby attracting, storing, or efficiently utilizing the carbon dioxide released from the adsorbent to the outside.

[0063] Here, in the case of reducing the pressure of the adsorption chamber when the carbon dioxide is released, in order to ensure the airtightness of the adsorption chamber, it is necessary to isolate the inlet and outlet of the adsorption chamber by using a damper with high sealing performance or the like. In addition, the adsorption chamber itself needs to be configured as a high pressure-resistant structure. However, as described above, preparing a damper with high sealing performance and an adsorption chamber with high pressure performance is disadvantageous in terms of manufacturing cost and maintenance cost. Therefore, the demand for a more economical and efficient carbon dioxide recovery device is increased. Therefore, in the present embodiment, the above-mentioned structure and method are adopted.

[0064] According to the above structure, the first adsorption section 11 first adsorbs carbon dioxide. After passing through the first adsorption section 11, the on-off valve 31 is opened to operate the suction section 50, thereby allowing the gas with a high carbon dioxide concentration to flow into the second adsorption section 21 while regenerating the first adsorption section 11. As a result, the second adsorption section 21 also adsorbs carbon dioxide. In this way, by connecting the device for adsorbing carbon dioxide in two stages, high-purity carbon dioxide can be efficiently recovered with a simple structure. In addition, when the separation of carbon dioxide from the first adsorption section 11 is completed, the first adsorption chamber 10 and the second adsorption chamber 20 can be separated by closing the on-off valve 31. Therefore, the adsorption of carbon dioxide can be re-performed in the first adsorption chamber 10, and the separation of carbon dioxide can be promoted in the second adsorption chamber 20. In this way, by separating the first adsorption chamber 10 and the second adsorption chamber 20, the absorption and separation cycles of the two can be independently operated, and the operation time can be shortened and carbon dioxide can be efficiently recovered.

[0065] Moreover, the porosity of the first adsorption section 11 is greater than that of the second adsorption section 21, and the volume of the first adsorption section 11 is greater than that of the second adsorption section 21. According to this structure, the first adsorption section 11 maintains a sufficient adsorption capacity, and can suppress pressure loss even when a large amount of air flows in, so that a higher operating efficiency can be achieved in the carbon dioxide adsorption operation. In addition, since the gas with a high carbon dioxide concentration flows into the second adsorption section 21, carbon dioxide can be efficiently adsorbed even if the porosity and volume are small. As a result, the size and size of each component can be made compact, reducing manufacturing costs and maintenance costs. In addition, due to the shape with fewer voids, the amount of residual gas in the device during the adsorption operation is reduced, and the purity of the recovered carbon dioxide can be improved.

[0066] In addition, according to the above-mentioned structure, the carbon dioxide adsorbed on the first adsorption section 11 can be easily detached only by heating the first adsorption section 11 with the first heating section 43. In particular, since two-stage adsorption is performed by the second adsorption section 21, it is not necessary to excessively increase the purity of carbon dioxide in the first adsorption section 11. Therefore, compared with other methods of using pressure fluctuations, it is not necessary to take measures such as excessively ensuring the airtightness of the first adsorption chamber 10. As a result, the sealing performance and pressure resistance performance required of each component can be suppressed to a low level. As a result, the manufacturing cost and maintenance cost of the device can be reduced.

[0067] The second desorption unit 42 further includes a water vapor supply unit 45 for supplying water vapor into the second adsorption chamber 20. According to this configuration, by supplying water vapor to the second adsorption chamber 20, carbon dioxide can be more efficiently desorbed from the second adsorption unit 21.

[0068] Moreover, in the above-mentioned carbon dioxide recovery method, first, the first adsorption unit 11 adsorbs carbon dioxide. After passing through the first adsorption unit 11, the suction unit 50 is operated by opening the on-off valve 31, thereby performing the regeneration of the first adsorption unit 11 while the gas with a high carbon dioxide concentration flows into the second adsorption unit 21. As a result, the second adsorption unit 21 also adsorbs carbon dioxide. In this way, by connecting the device for adsorbing carbon dioxide in two stages, carbon dioxide can be efficiently recovered with a simple structure. Moreover, when the separation of carbon dioxide from the first adsorption unit 11 is completed, the first adsorption chamber 10 and the second adsorption chamber 20 can be separated by closing the on-off valve 31. Therefore, the adsorption of carbon dioxide can be re-performed in the first adsorption chamber 10, and the separation of carbon dioxide can be promoted in the second adsorption chamber 20. In this way, by being able to separate the first adsorption chamber 10 and the second adsorption chamber 20, the cycles of absorption and separation of the two can be made independent, and the operation time can be shortened and carbon dioxide can be efficiently recovered. Specifically, the step of adsorbing carbon dioxide on the first adsorption unit 11 and the step of separating and guiding the carbon dioxide adsorbed on the second adsorption unit 21 to the outside are performed independently. This can shorten the time required for the entire recovery operation and reduce the operating cost of the device.

[0069] (Other Embodiments)

[0070] As mentioned above, although the embodiment of this disclosure is described in detail with reference to drawings, the specific structure is not limited to this embodiment, and design changes and the like within the scope not departing from the gist of this disclosure are also included.

[0071] For example, as a modification, Figure 5As shown, a structure may also be adopted that includes a plurality of (two as an example) first adsorption chambers 10 arranged in parallel with each other and a plurality of (two as an example) second adsorption chambers 20 connected in parallel. In this case, it is preferred that the total value of the porosity and volume in the plurality of second adsorption sections 21 is smaller than the total value of the plurality of first adsorption sections 11. It should be noted that Figure 5 In the example, a structure in which two first adsorption chambers 10 and two second adsorption chambers 20 are provided respectively is shown, but the number of second adsorption chambers 20 can also be made smaller than the number of first adsorption chambers 10 by the adsorption and desorption performance of the adsorbent material. In this case, the size of the carbon dioxide recovery device 1 can be made more compact. In addition, for example, if the adsorption time in the first adsorption chamber 10 is considerably longer than the time taken for the regeneration of the second adsorption section 21 of the second adsorption chamber 20, it is possible to adopt a structure in which the first adsorption chamber 10 is connected in parallel, the timing of the regeneration of the two is staggered, and the adsorption time of the second adsorption section 21 is increased. In addition, the opposite relationship can also be established.

[0072] According to this structure, by having a plurality of first adsorption parts 11 arranged in parallel and a plurality of second adsorption parts 21 arranged in parallel, the system structure can be changed to match the performance of the adsorption material filled in the first adsorption part 11 and the second adsorption part 21. As a result, regardless of the type of adsorption material, ideal operating conditions matching each adsorbent can be achieved.

[0073] In addition, if Figure 6 As shown, another damper 13 may be provided on the air inlet 10a side of the first adsorption chamber 10. In this case, when air is sucked from the first adsorption chamber 10 to recover carbon dioxide, air is less likely to enter from the outside, so the carbon dioxide concentration of the recovered gas can be further increased.

[0074] Furthermore, in the above embodiment, an example of temperature variation using the second heating unit 44 and the water vapor supply unit 45 as the second detachment unit 42 is described. However, the second detachment unit 42 is not limited thereto, and a device for performing pressure variation may be provided as the second detachment unit 42. In addition, in the above embodiment, a two-stage structure having the first adsorption unit 11 and the second adsorption unit 21 is adopted, but it is not limited thereto, and a plurality of structures of three or more stages may be adopted. According to this structure, a higher concentration of carbon dioxide can be recovered.

[0075] <Note>

[0076] The carbon dioxide recovery device 1 and the carbon dioxide recovery method described in each embodiment can be understood, for example, as follows.

[0077] (1) A carbon dioxide recovery device 1 of the first embodiment comprises: a first adsorption chamber 10 having an air intake port 10a and an air exhaust port 10b open to the atmosphere; a fan 12 for forming an air flow in a direction from the air intake port 10a toward the air exhaust port 10b; a damper 13 for closing the air exhaust port 10b; a first adsorption unit 11 disposed in the first adsorption chamber 10 and capable of adsorbing carbon dioxide contained in the air; a second adsorption chamber 20 disposed together with the first adsorption chamber 10; and a connecting pipe 30 for connecting the first adsorption chamber 10 with the second adsorption chamber 20. A second adsorption chamber 20 is connected; a second adsorption section 21, which is arranged in the second adsorption chamber 20 and can adsorb carbon dioxide contained in the gas flowing in from the connecting pipe 30; an opening and closing valve 31, which is set on the connecting pipe 30; a first separation section 41, which separates the carbon dioxide absorbed by the first adsorption section 11; a second separation section 42, which separates the carbon dioxide absorbed by the second adsorption section 21; and a suction section 50, which is connected to the second adsorption section 21 and can suck the gas in the first adsorption chamber 10 and the second adsorption chamber 20.

[0078] According to the above structure, first, the first adsorption unit 11 adsorbs carbon dioxide. After passing through the first adsorption unit 11, the suction unit 50 is operated by opening the on-off valve 31, thereby regenerating the first adsorption unit 11 and simultaneously causing the gas with a high carbon dioxide concentration to flow into the second adsorption unit 21. Thus, the second adsorption unit 21 also adsorbs carbon dioxide. In this way, by connecting the device for adsorbing carbon dioxide in two stages, carbon dioxide can be efficiently recovered with a simple structure.

[0079] (2) The carbon dioxide recovery device 1 of the second embodiment is the carbon dioxide recovery device 1 of the first embodiment, wherein the porosity of the first adsorption unit 11 is greater than the porosity of the second adsorption unit 21 , and the volume of the first adsorption unit 11 is greater than the volume of the second adsorption unit 21 .

[0080] According to the above structure, since a large amount of air (atmosphere) flows into the first adsorption part 11, the porosity is high and the volume is large, so that the pressure loss can be reduced and more carbon dioxide can be adsorbed. In addition, since the gas with a high carbon dioxide concentration flows into the second adsorption part 21, even if the porosity is small and the volume is small, carbon dioxide can be efficiently adsorbed. As a result, the manufacturing cost and maintenance cost of each component can be reduced.

[0081] (3) The carbon dioxide recovery device 1 according to a third aspect is the carbon dioxide recovery device 1 according to the first or second aspect, wherein the first desorption unit 41 is a first heating unit 43 capable of heating the first adsorption unit 11 .

[0082] According to the above configuration, carbon dioxide adsorbed to the first adsorption unit 11 can be easily released simply by heating the first adsorption unit 11 with the first heating unit 43. In other words, compared with other methods using pressure fluctuations, the sealing performance and pressure resistance required of each component can be reduced, and costs can be reduced.

[0083] (4) The carbon dioxide recovery device 1 according to a fourth aspect is the carbon dioxide recovery device 1 according to any one of the first to third aspects, wherein the second desorption unit 42 is a second heating unit 44 capable of heating the second adsorption unit 21 .

[0084] According to the above configuration, carbon dioxide adsorbed to the second adsorption unit 21 can be easily released simply by heating the second adsorption unit 21 with the second heating unit 44. In other words, compared with other methods using pressure fluctuations, the sealing performance and pressure resistance required of each component can be reduced, and costs can be reduced.

[0085] (5) The carbon dioxide recovery device 1 of the fifth embodiment is based on the carbon dioxide recovery device of any one of the first to third embodiments, wherein the second separation section 42 is the suction section 50 connected to the second adsorption section 21 and capable of sucking the gas in the second adsorption chamber 20.

[0086] According to the above configuration, it is not necessary to provide another device for heating the second adsorption unit 21 , and carbon dioxide can be easily desorbed from the second adsorption unit 21 only by the suction of the suction unit 50 .

[0087] (6) The carbon dioxide recovery device 1 according to a sixth aspect is the carbon dioxide recovery device 1 according to any one of the first to fifth aspects, wherein the second separation unit 42 further includes a water vapor supply unit 45 for supplying water vapor into the second adsorption chamber 20 .

[0088] According to the above configuration, by supplying water vapor to the second adsorption chamber 20 , it is possible to more efficiently desorb carbon dioxide from the second adsorption section 21 .

[0089] (7) The carbon dioxide recovery device 1 of the seventh embodiment is based on the carbon dioxide recovery device 1 of any one of the first to sixth embodiments, and further includes a plurality of the first adsorption chambers 10 and the first adsorption parts 11 that are arranged in a single manner or in parallel with each other, and a plurality of the second adsorption chambers 20 and the second adsorption parts 21 that are arranged in a single manner or in parallel with each other.

[0090] According to the above configuration, by providing a single or a plurality of first adsorption units 11 arranged in parallel and a single or a plurality of second adsorption units 21 arranged in parallel, it is possible to recover a large amount of carbon dioxide with a higher purity in a short time.

[0091] (8) The carbon dioxide recovery device 1 according to an eighth aspect is the carbon dioxide recovery device 1 according to the seventh aspect, wherein the total value of the porosity and volume of the plurality of second adsorption units 21 is smaller than the total value of the porosity and volume of the plurality of first adsorption units 11 .

[0092] According to the above structure, the first adsorption part 11 maintains sufficient adsorption capacity and can suppress pressure loss even when a large amount of air flows in, so that a high operating efficiency can be achieved in the carbon dioxide adsorption operation. In addition, since gas with a high carbon dioxide concentration flows into the second adsorption part 21, carbon dioxide can be efficiently adsorbed even if the porosity and volume are small. As a result, the size and size of each component can be made compact, and the manufacturing cost and maintenance cost can be reduced.

[0093] (9) The carbon dioxide recovery method of the ninth scheme is a carbon dioxide recovery method using the carbon dioxide recovery device 1 of the first scheme, wherein the carbon dioxide recovery method includes the following steps: in a state where the on-off valve 31 is closed, by opening the damper 13 and driving the fan 12, carbon dioxide is adsorbed on the first adsorption section 11; in a state where the damper 13 is closed and the on-off valve 31 is opened, the first separation section 41 is driven to separate the carbon dioxide adsorbed on the first adsorption section 11, and the gas containing the separated carbon dioxide is guided to the second adsorption chamber 20 through the connecting pipe 30 by driving the suction section 50, thereby carbon dioxide is adsorbed on the second adsorption section 21; and in a state where the on-off valve 31 is closed, the carbon dioxide adsorbed on the second adsorption section 21 is separated and guided to the outside by driving the suction section 50 and the second separation section 42, and the step of adsorbing carbon dioxide on the first adsorption section 11 and the step of separating carbon dioxide adsorbed on the second adsorption section 21 and guiding it to the outside are performed in parallel.

[0094] According to the above structure, first, the first adsorption section 11 adsorbs carbon dioxide. After passing through the first adsorption section 11, the suction section 50 is activated by opening the on-off valve 31, thereby allowing the gas with a high carbon dioxide concentration to flow into the second adsorption section 21 while the first adsorption section 11 is being regenerated. As a result, the second adsorption section 21 also adsorbs carbon dioxide. In this way, by connecting the device for adsorbing carbon dioxide in two stages, carbon dioxide can be efficiently recovered with a simple structure. In addition, the step of adsorbing carbon dioxide on the first adsorption section 11 and the step of detaching the carbon dioxide adsorbed on the second adsorption section 21 and guiding it to the outside are performed in parallel. As a result, the time required for the overall recovery operation can be shortened, and the operating cost of the device can be reduced.

[0095] Industrial Applicability

[0096] The present disclosure relates to an economical and efficient carbon dioxide recovery device and a carbon dioxide recovery method.

[0097] Description of reference numerals:

[0098] 1…Carbon dioxide recovery device

[0099] 10…First adsorption chamber

[0100] 10a…Intake port

[0101] 10b…Exhaust port

[0102] 11…First adsorption part

[0103] 12… Fan

[0104] 13…Damper

[0105] 20…Second adsorption chamber

[0106] 21…Second adsorption part

[0107] 30…Connection pipe

[0108] 31…On / off valve

[0109] 32…First cooler

[0110] 41…First separation unit

[0111] 42…Second separation unit

[0112] 43…first heating unit

[0113] 44…Second heating unit

[0114] 45…Steam supply unit

[0115] 50…Attraction

[0116] 61…Second cooler

[0117] 70…Concentration measurement unit

[0118] 71…First concentration meter

[0119] 72…Second concentration meter

[0120] 73…Third concentration meter

[0121] 74…Fourth concentration meter

[0122] 80…Recovery pipe

[0123] 81…Atmosphere release pipe

[0124] 82…Condensate drain pipe

[0125] 91…First opening and closing valve

[0126] 92…Second on-off valve

[0127] 93…The third on-off valve

[0128] 94 ...a fourth on-off valve.

Claims

1. A carbon dioxide recovery device, wherein: The carbon dioxide recovery device comprises: A first adsorption chamber having an air intake port and an air exhaust port open to the atmosphere; a fan for forming a flow of air in a direction from the air intake port toward the air exhaust port; a damper capable of closing the exhaust port; A first adsorption unit is disposed in the first adsorption chamber and is capable of adsorbing carbon dioxide contained in the air; A second adsorption chamber, which is provided together with the first adsorption chamber; a connecting pipe connecting the first adsorption chamber and the second adsorption chamber; a second adsorption unit disposed in the second adsorption chamber and capable of adsorbing carbon dioxide contained in the gas flowing in from the connecting pipe; an on-off valve, which is arranged on the connecting pipe; a first desorption unit for desorption of carbon dioxide absorbed by the first adsorption unit; a second desorption section for desorption of carbon dioxide absorbed by the second adsorption section; as well as The suction unit is connected to the second adsorption unit and is capable of sucking the gas in the first adsorption chamber and the second adsorption chamber.

2. The carbon dioxide recovery device according to claim 1, wherein: The porosity of the first adsorption portion is greater than that of the second adsorption portion, and the volume of the first adsorption portion is greater than that of the second adsorption portion.

3. The carbon dioxide recovery device according to claim 1 or 2, wherein: The first detaching portion is a first heating portion capable of heating the first adsorption portion.

4. The carbon dioxide recovery device according to claim 1 or 2, wherein: The second separation portion is a second heating portion capable of heating the second adsorption portion.

5. The carbon dioxide recovery device according to claim 1 or 2, wherein: The second desorption unit is the suction unit connected to the second adsorption unit and capable of sucking the gas in the second adsorption chamber.

6. The carbon dioxide recovery device according to claim 1 or 2, wherein: The second desorption unit further includes a water vapor supply unit that supplies water vapor to the second adsorption chamber.

7. The carbon dioxide recovery device according to claim 1, wherein: The carbon dioxide recovery device further includes a single first adsorption chamber and a plurality of first adsorption parts arranged in parallel, and a single second adsorption chamber and a plurality of second adsorption parts arranged in parallel.

8. The carbon dioxide recovery device according to claim 7, wherein: The total value of the porosity and the volume of the plurality of second adsorption parts is smaller than the total value of the porosity and the volume of the plurality of first adsorption parts.

9. A method for recovering carbon dioxide, which is a method for recovering carbon dioxide using the carbon dioxide recovery device according to claim 1, wherein: The carbon dioxide recovery method comprises the following steps: In a state where the on-off valve is closed, the damper is opened and the fan is driven, thereby allowing carbon dioxide to be adsorbed on the first adsorption portion; In a state where the damper is closed and the on-off valve is opened, the first separation portion is driven to separate the carbon dioxide adsorbed on the first adsorption portion, and the gas containing the separated carbon dioxide is guided to the second adsorption chamber through the connecting pipe by driving the suction portion, so that the carbon dioxide is adsorbed on the second adsorption portion; and In a state where the on-off valve is closed, the suction unit and the second separation unit are driven to separate the carbon dioxide adsorbed on the second adsorption unit and guide it to the outside. The step of allowing the first adsorption unit to adsorb carbon dioxide and the step of desorbing the carbon dioxide adsorbed on the second adsorption unit and introducing the carbon dioxide to the outside are performed in parallel.

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