Carbon dioxide separation and recovery apparatus

Abstract

The carbon dioxide separation and recovery apparatus of one embodiment of the present disclosure includes an adsorption treatment chamber that performs an adsorption treatment of adsorbing carbon dioxide contained in air to a particulate adsorbent material housed inside by bringing the air into contact with the adsorbent material, and a regeneration treatment chamber that performs a regeneration treatment of desorbing carbon dioxide from the adsorbent material by bringing low-temperature vapor into contact with the adsorbent material in a state where the inside is under a negative pressure. The adsorption treatment chamber takes the adsorbent material subjected to the regeneration treatment in the regeneration treatment chamber into the inside, performs the adsorption treatment using the taken-in adsorbent material, and the regeneration treatment chamber takes the adsorbent material used for the adsorption treatment in the adsorption treatment chamber into the inside, performs the regeneration treatment for the taken-in adsorbent material.

Description

Technical Field

[0001] This disclosure relates to atmospheric carbon dioxide separation and recovery equipment for separating and recovering carbon dioxide from the atmosphere. Background Technology

[0002] Patent Document 1 discloses a technique in which carbon dioxide in the air is adsorbed onto a particulate adsorbent material, and then the adsorbent material is regenerated by separating the carbon dioxide from the adsorbent material using steam, which is a form of process heat.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2022-20723 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] In atmospheric carbon dioxide separation and recovery equipment, the adsorbent material can be efficiently regenerated by using high-temperature steam during the regeneration process. However, generating high-temperature steam requires significant energy, and releasing carbon dioxide to obtain this energy defeats the purpose. Furthermore, even if waste heat from certain equipment can be used to generate high-temperature steam, the high-temperature steam has high utilization value and would compete with other equipment. Therefore, the object of this disclosure is to provide an atmospheric carbon dioxide separation and recovery equipment capable of using low-temperature steam for the regeneration of the adsorbent material.

[0008] The problem that the invention aims to solve

[0009] One aspect of the atmospheric carbon dioxide separation and recovery apparatus disclosed herein includes: an adsorption treatment chamber for adsorbing carbon dioxide contained in the atmosphere onto the adsorption material by contacting the atmosphere with a particulate adsorption material housed therein; and a regeneration treatment chamber for regenerating carbon dioxide from the adsorption material by contacting the adsorption material with low-temperature vapor under negative pressure, wherein the adsorption treatment chamber takes in the adsorption material that has been regenerated in the regeneration treatment chamber and performs adsorption treatment using the taken-in adsorption material, and the regeneration treatment chamber takes in the adsorption material used for adsorption treatment in the adsorption treatment chamber and performs regeneration treatment on the taken-in adsorption material.

[0010] Invention Effects

[0011] Based on this structure, an atmospheric carbon dioxide separation and recovery device can be provided that can use low-temperature steam to regenerate the adsorbent material. Attached Figure Description

[0012] Figure 1 This is a conceptual diagram of a device for separating and recovering carbon dioxide from the atmosphere.

[0013] Figure 2 This is a diagram showing the adsorption treatment chamber as viewed from the inflow side.

[0014] Figure 3 This is a diagram showing the adsorption treatment chamber viewed from the outflow side. Detailed Implementation

[0015] (Overall structure)

[0016] The following describes the implementation method. First, the overall structure of the atmospheric carbon dioxide separation and recovery device (hereinafter referred to as the "separation and recovery device") 100 of the implementation method will be described. Figure 1 This is a conceptual diagram of the separation and recovery device 100. The separation and recovery device 100 is a device that separates and recovers carbon dioxide from the atmosphere. That is, the separation and recovery device 100 is a Direct Air Capture (DAC) device.

[0017] like Figure 1 As shown, the separation and recovery equipment 100 includes an adsorption treatment chamber 10, a regeneration treatment chamber 20, a temperature adjustment device 30, and an attraction device 40. These components will be described in detail below.

[0018] <Adsorption Treatment Chamber>

[0019] The adsorption treatment chamber 10 is a chamber for carrying out adsorption treatment in which carbon dioxide in the atmosphere is adsorbed onto the adsorbent material. Figure 1 The diagram depicts two adsorption treatment chambers 10, but the number of adsorption treatment chambers 10 in the separation and recovery device 100 is not limited. The adsorbent used in the adsorption treatment is the adsorbent that has been regenerated in the regeneration treatment chamber 20, described later. The adsorption treatment chamber 10 takes in the adsorbent that has been regenerated in the regeneration treatment chamber 20 and uses the taken-in adsorbent to perform adsorption treatment. Atmosphere passes through the interior of the adsorption treatment chamber 10 containing the adsorbent and comes into contact with the adsorbent. As a result, carbon dioxide in the atmosphere is adsorbed by the adsorbent and recovered.

[0020] The adsorbent in this embodiment is particulate and is formed by impregnating an amine onto a porous support. However, the adsorbent is not limited to the above-described adsorbent. The adsorbent has the following characteristics: the amount of adsorbable carbon dioxide increases as the temperature decreases, and the amount of adsorbable carbon dioxide increases as the ambient pressure increases. Therefore, carbon dioxide adsorbed in the adsorbent detaches from the adsorbent when the temperature of the adsorbent rises, and also detaches from the adsorbent when the ambient pressure decreases.

[0021] The adsorption treatment chamber 10 has a plate-like shape and extends vertically. The adsorption treatment chamber 10 includes an inflow surface 11 corresponding to one main surface and an outflow surface 12 corresponding to another main surface. Figure 2 This is a diagram showing the adsorption treatment chamber 10 as viewed from the inflow side 11. Figure 3 This is a view of the adsorption treatment chamber 10 from the outflow surface 12 side. The inflow surface 11 and the outflow surface 12 are formed, for example, by a mesh-like component. Figure 2 As shown, air flows from the outside of the adsorption treatment chamber 10 into the interior of the adsorption treatment chamber 10 via the inflow surface 11. Additionally, as... Figure 3 As shown, the air flowing into the adsorption treatment chamber 10 passes through the gaps in the adsorption material and flows out to the outside of the adsorption treatment chamber 10 via the outflow surface 12.

[0022] The adsorption treatment chamber 10 includes a supply port 13 for taking in adsorbent material and a discharge port 14 for discharging the adsorbent material used. In this embodiment, the supply port 13 is located at the upper end of the adsorption treatment chamber 10, and the discharge port 14 is located at the lower end of the adsorption treatment chamber 10. Figure 1 As shown, the adsorbent material discharged from the adsorption treatment chamber 10 is transferred to the regeneration treatment chamber 20 by the transfer device 15 and supplied to the regeneration treatment chamber 20. The transfer device 15 is, for example, a bucket conveyor or an air conveyor. However, if the regeneration treatment chamber 20 is located below the adsorption treatment chamber 10, the adsorbent material can also be supplied from the adsorption treatment chamber 10 to the regeneration treatment chamber 20 by its own weight.

[0023] <Regeneration Processing Room>

[0024] The regeneration chamber 20 is a chamber in which a regeneration process is performed to remove carbon dioxide from the adsorbent material. The adsorbent material to be regenerated is the adsorbent material used for adsorption in the adsorption chamber 10. The regeneration chamber 20 takes the adsorbent material used for adsorption in the adsorption chamber 10 into its interior, and brings the taken-in adsorbent material into contact with vapor, thereby performing the regeneration process. In this embodiment, the regeneration chamber 20 is a sealable container. The regeneration chamber 20 includes a supply port 21 for taking in the adsorbent material used in the adsorption process and a discharge port 22 for discharging the regenerated adsorbent material. In this embodiment, the supply port 21 is located at the upper end of the regeneration chamber 20, and the discharge port 22 is located at the lower end of the regeneration chamber 20.

[0025] The carbon dioxide that has been removed from the adsorbent material through the regeneration process is discharged to a carbon dioxide container (not shown) via the discharge pump 23. The regeneration chamber 20 may be located below the adsorption chamber 10, above the adsorption chamber 10, or at the same height as the adsorption chamber 10.

[0026] One method for regeneration is to raise the temperature of the adsorbent material. This method typically involves indirect heating of the adsorbent material by applying heat to the walls of a tower containing the material. However, such indirect heating makes it difficult to transfer heat to the adsorbent material located near the center of the tower. Furthermore, when the adsorbent material is in particulate form, heat is transferred to each adsorbent material via contact points between adjacent materials, resulting in poor heat transfer efficiency. In contrast, this embodiment uses steam for regeneration, allowing steam to directly heat the particulate adsorbent material by entering the gaps between them. Therefore, heat utilization efficiency is high compared to indirect heating. However, regeneration by heating alone requires high-temperature steam of around 100°C. Generating such high-temperature steam requires significant energy. Furthermore, even if waste heat from certain equipment can be used to generate high-temperature steam, the high value of high-temperature steam as a heat source leads to competition with other equipment, such as power generation equipment.

[0027] Therefore, in this embodiment, as a regeneration process, in addition to raising the temperature of the adsorbent material using steam, a method for reducing the pressure around the adsorbent material is also implemented to suppress the temperature of the steam used. Specifically, the adsorbent material supplied from the adsorption treatment chamber 10 is taken into the interior of the regeneration treatment chamber 20, and low-temperature steam is brought into contact with the taken-in adsorbent material while the interior of the regeneration treatment chamber 20 is under negative pressure. To create a negative pressure inside the regeneration treatment chamber 20, a discharge pump 23 that removes carbon dioxide from the regeneration treatment chamber 20 can be used, for example. Furthermore, "low-temperature steam" refers to steam, for example, below 100°C.

[0028] In this embodiment, the pressure inside the regeneration chamber 20 is set to negative, so that even if the steam used in the regeneration process is at a low temperature, carbon dioxide can be sufficiently removed from the adsorbent material. Furthermore, by using low-temperature steam in the regeneration process, the energy required for steam generation can be reduced, and any unused low-temperature steam can be utilized. Therefore, the overall energy consumption of the separation and recovery device 100 can be suppressed.

[0029] Furthermore, by using low-temperature steam in the regeneration process, it is also expected to suppress the secondary effect of adsorbent material degradation. In amine-loaded adsorbent materials, the carbon dioxide absorption capacity decreases due to degradation such as amine volatilization, thermal degradation, and oxidative degradation. However, the lower the steam temperature used, the more effectively these degradations are suppressed. Therefore, according to this embodiment, the frequency of adsorbent material replacement is reduced compared to the case of performing a general regeneration process using a high-temperature heat source.

[0030] The regenerated adsorbent material is discharged from the outlet 22 of the regeneration chamber 20. The adsorbent material discharged from the regeneration chamber 20 is transferred to the adsorption chamber 10 via a transfer device 24 and supplied to the adsorption chamber 10. The transfer device 24 is, for example, a bucket conveyor or an air conveyor. However, if the adsorption chamber 10 is located below the regeneration chamber 20, the adsorbent material can also be supplied from the regeneration chamber 20 to the adsorption chamber 10 by its own weight.

[0031] Furthermore, unlike this embodiment, in apparatuses that perform adsorption and regeneration processes within the same processing chamber, the chamber is cooled by atmospheric flow during adsorption. Therefore, when regeneration is subsequently performed, the cooled chamber needs to be reheated using steam or a heating device. In contrast, in this embodiment, since the processing chambers are separated, the aforementioned reheating is unnecessary, thus reducing energy consumption.

[0032] <Temperature Adjustment Device>

[0033] The temperature adjustment device 30 is a device for maintaining or heating the regeneration chamber 20. In this embodiment, the temperature adjustment device 30 heats the regeneration chamber 20 so that the internal temperature of the regeneration chamber 20 reaches or exceeds a predetermined value during the regeneration process. This predetermined value is, for example, 50 to 100°C. This further suppresses the energy of the vapor used and allows carbon dioxide to be fully removed from the adsorbent material.

[0034] <Attraction Device>

[0035] The suction device 40 is a device for drawing in the atmosphere inside the adsorption treatment chamber 10. For example... Figure 3 As shown, the suction device 40 is located outside the adsorption treatment chamber 10 and on the outflow surface 12 side. In this embodiment, the suction device 40 is, for example, a fan, but it is not limited to this; for example, it could be a negative pressure tank, a pipe connected to a negative pressure chimney, or the like. Alternatively, the separation and recovery equipment 100 may have an air supply device, such as a fan, that supplies air to the inflow surface 11 of the adsorption treatment chamber 10 instead of the suction device 40.

[0036] The suction device 40 draws in the air inside the adsorption treatment chamber 10 via the outflow surface 12, thereby allowing the air to flow from the outside of the adsorption treatment chamber 10 into the interior of the adsorption treatment chamber 10 via the inflow surface 11. Thus, in this embodiment, instead of using an air supply device that delivers air toward the inflow surface 11 of the adsorption treatment chamber 10, the suction device 40 is used to draw the air into the interior of the adsorption treatment chamber 10.

[0037] Therefore, according to this embodiment, the temperature of the air flowing into the adsorption treatment chamber 10 can be prevented from rising as it passes through the air supply device. As described above, the lower the temperature of the adsorbent material, the easier it is to adsorb carbon dioxide. In this embodiment, the lower temperature air flows into the adsorption treatment chamber 10, thus suppressing the temperature rise of the adsorbent material caused by the air and enabling efficient adsorption treatment.

[0038] (The operation of the separation and recycling equipment)

[0039] Next, the operation of the separation and recovery device 100 will be explained. For simplicity, the separation and recovery device 100 has two adsorption treatment chambers 10 and one regeneration treatment chamber 20. Furthermore, the volume of each adsorption treatment chamber 10 is equal to the volume of the regeneration treatment chamber 20. In addition, the adsorption treatment time is twice the regeneration treatment time. Specifically, the adsorption treatment time is set to 2 hours, and the regeneration treatment time is set to 1 hour. The "adsorption treatment time" refers to the time during which the adsorption material is used for adsorption treatment before it is taken into and discharged from the adsorption treatment chamber 10. Similarly, the "regeneration treatment time" refers to the time during which the adsorption material is regenerated before it is taken into and discharged from the regeneration treatment chamber 20.

[0040] First, the separation and recovery equipment 100 simultaneously performs adsorption and regeneration processes. The adsorption process is carried out separately in two adsorption chambers 10. Specifically, with adsorbent material contained in both adsorption chambers 10, the corresponding suction devices 40 are activated. As a result, atmospheric air flows into the two adsorption chambers 10 and passes through their interiors, where carbon dioxide is adsorbed onto the adsorbent material and recovered.

[0041] On the other hand, in the regeneration process, the adsorbent material used in the adsorption process is placed in the regeneration chamber 20 and the regeneration chamber 20 is sealed. Furthermore, while maintaining a negative pressure inside the regeneration chamber 20, low-temperature steam is supplied to the regeneration chamber 20. As a result, carbon dioxide is released from the adsorbent material, and the adsorbent material is regenerated. At this time, the temperature adjustment device 30 maintains or heats the regeneration chamber 20, thereby keeping the temperature inside the regeneration chamber 20 above a predetermined value.

[0042] Next, when the regeneration process ends after 1 hour, the suction device 40 corresponding to one of the two adsorption chambers 10 is stopped, and the adsorption process in that adsorption chamber 10 ends. At this time, the adsorption process in the other adsorption chamber 10 continues.

[0043] After the adsorption treatment is completed, the adsorption treatment chamber 10 discharges all the adsorbent material used in the adsorption treatment and supplies it to the regeneration treatment chamber 20. At the same time, the regeneration treatment chamber 20 discharges all the adsorbent material that has undergone regeneration treatment and supplies it to the adsorption treatment chamber 10 after the adsorption treatment is completed. That is, the adsorbent material is replaced between the adsorption treatment chamber 10 after the adsorption treatment is completed and the regeneration treatment chamber 20.

[0044] Next, regeneration is initiated again in regeneration chamber 20, and adsorption is also initiated again in adsorption chamber 10 with the adsorbent material replaced. Afterwards, when regeneration is completed after 1 hour, the adsorbent material is replaced between adsorption chamber 10 (the chamber where the adsorbent material was replaced) and regeneration chamber 20. After the adsorbent material replacement is completed, regeneration is initiated again in regeneration chamber 20, and adsorption is again initiated again in adsorption chamber 10 with the adsorbent material replaced.

[0045] In this way, by alternating the replacement of the adsorbent material in the two adsorption treatment chambers 10 every hour, replacing the adsorbent material in the regeneration treatment chamber 20 every hour, and replacing the adsorbent material in each adsorption treatment chamber 10 every two hours, the adsorption and regeneration processes can be continuously performed even when the adsorption treatment time (2 hours in the example above) and the regeneration treatment time (1 hour in the example above) are different.

[0046] The operation of the separation and recovery equipment 100 has been described above, but the operation of the separation and recovery equipment 100 is not limited to the above-described operation. For example, the adsorbent material in the adsorption treatment chamber 10 is replaced all at once, but the adsorbent material can also be replaced multiple times in the adsorption treatment chamber 10. In addition, the absorbent discharged from the regeneration treatment chamber 20 can also be temporarily stored in a container not shown in the figure and supplied to the adsorption treatment chamber 10 from that container.

[0047] Furthermore, while the adsorption treatment time is twice the regeneration treatment time, it can also be more than twice the regeneration treatment time. In this embodiment, the separation and recovery device 100 adsorbs atmospheric carbon dioxide onto the adsorbent material, but the amount of carbon dioxide contained in the atmosphere is far less than the amount contained in the waste gas. Therefore, the adsorbent material can sufficiently adsorb carbon dioxide even when exposed to the atmosphere for a long time. Thus, as in this embodiment, by ensuring a longer adsorption treatment time, the capacity of the adsorbent material can be fully utilized, enabling highly efficient adsorption treatment.

[0048] Furthermore, as described above, the separation and recovery apparatus 100 of this embodiment directly supplies the adsorbent material regenerated in the regeneration chamber 20 to the adsorption chamber 10. That is, the adsorbent material that is in contact with vapor in the regeneration chamber 20 is supplied to the adsorption chamber 10 in a moist state. In the separation and recovery apparatus 100 of this embodiment, as described above, since the adsorption treatment time is long, the adsorbent material stored in the adsorption chamber 10 is exposed to the flowing atmosphere for a long time. Therefore, a drying treatment using the atmosphere to dry the adsorbent material can be performed in the adsorption chamber 10. Therefore, according to this embodiment, by performing the drying treatment simultaneously with the adsorption treatment in the adsorption chamber 10, the drying chamber can be omitted, the structure of the separation and recovery apparatus 100 can be simplified, and the energy consumption of the separation and recovery apparatus 100 can be reduced.

[0049] (Summarize)

[0050] The first item disclosed in this specification is an atmospheric carbon dioxide separation and recovery device, comprising: an adsorption treatment chamber for adsorbing carbon dioxide contained in the atmosphere into the adsorption material by contacting the atmosphere with the particulate adsorption material contained therein; and a regeneration treatment chamber for regenerating carbon dioxide from the adsorption material by contacting the adsorption material with low-temperature vapor under negative pressure, wherein the adsorption treatment chamber takes the adsorption material that has been regenerated in the regeneration treatment chamber into its interior and uses the taken-in adsorption material for adsorption treatment, and the regeneration treatment chamber takes the adsorption material used for adsorption treatment in the adsorption treatment chamber into its interior and performs regeneration treatment on the taken-in adsorption material.

[0051] According to this structure, even if the steam used is at a low temperature, carbon dioxide can be sufficiently removed from the adsorbent material. Furthermore, by using low-temperature steam in the regeneration process, the energy required for steam generation can be reduced when generating steam for regeneration, and unused low-temperature steam can be utilized. Therefore, as a whole, the energy consumption of the carbon dioxide separation and recovery device in the atmosphere can be suppressed.

[0052] The second item disclosed in this specification, according to the carbon dioxide separation and recovery device in the atmosphere described in the first item, wherein, in the adsorption treatment chamber, the adsorbent material that has been in contact with vapor in the regeneration treatment chamber is taken into the interior in a moist state, so that the atmosphere comes into contact with the taken-in adsorbent material, thereby performing the adsorption treatment, and at the same time, a drying treatment is performed to dry the taken-in adsorbent material.

[0053] According to this structure, there is no need to set up a separate drying chamber for drying treatment from the adsorption treatment chamber. Therefore, the structure of the carbon dioxide separation and recovery equipment in the atmosphere can be simplified, and the energy consumption of the carbon dioxide separation and recovery equipment in the atmosphere can also be reduced.

[0054] The third item disclosed in this specification, based on the atmospheric carbon dioxide separation and recovery device of the first item, wherein the adsorption treatment time for performing the adsorption treatment with the adsorbent material before taking it in and discharging it in the adsorption treatment chamber is more than twice the regeneration treatment time for performing the regeneration treatment with the adsorbent material before taking it in and discharging it in the regeneration treatment chamber.

[0055] Based on this structure, efficient adsorption treatment can be achieved by ensuring a longer adsorption treatment time.

[0056] The fourth item disclosed in this specification describes an atmospheric carbon dioxide separation and recovery device according to any one of items 1 to 3, wherein the atmospheric carbon dioxide separation and recovery device has a temperature adjustment device that, during the regeneration process in the regeneration chamber, maintains or heats the regeneration chamber such that the internal temperature of the regeneration chamber reaches a predetermined value or higher.

[0057] Based on this structure, the temperature of the vapor used can be further suppressed, and carbon dioxide can be fully removed from the adsorbent material.

[0058] The fifth item disclosed in this specification describes an atmospheric carbon dioxide separation and recovery apparatus according to any one of items 1 to 4, wherein the adsorption treatment chamber comprises: an inflow surface for air to flow from the outside of the adsorption treatment chamber into the interior of the adsorption treatment chamber; and an outflow surface for air to flow from the interior of the adsorption treatment chamber to the outside of the adsorption treatment chamber. The atmospheric carbon dioxide separation and recovery apparatus has an attraction device located outside the adsorption treatment chamber, which attracts air from the interior of the adsorption treatment chamber via the outflow surface, thereby causing air to flow from the outside of the adsorption treatment chamber into the interior of the adsorption treatment chamber via the inflow surface.

[0059] According to this structure, the temperature of the atmosphere flowing into the adsorption treatment chamber can be suppressed, thereby suppressing the temperature rise of the adsorption material and enabling efficient adsorption treatment.

Claims

1. A device for separating and recovering carbon dioxide from the atmosphere, comprising: An adsorption treatment chamber that performs adsorption treatment by contacting atmospheric air with particulate adsorbent material housed inside, thereby adsorbing carbon dioxide contained in the atmosphere onto the adsorbent material; and The regeneration chamber regenerates carbon dioxide by contacting the adsorbent material with low-temperature steam under negative pressure, thereby removing carbon dioxide from the adsorbent material. The adsorption treatment chamber takes the adsorbent material that has been regenerated in the regeneration treatment chamber and puts it inside, using the taken-in adsorbent material to carry out adsorption treatment. The regeneration chamber takes the adsorbent material used for adsorption treatment in the adsorption chamber and puts it into the chamber to regenerate the adsorbent material.

2. The atmospheric carbon dioxide separation and recovery equipment according to claim 1, wherein, In the adsorption treatment chamber, the adsorbent material that has been in contact with vapor in the regeneration treatment chamber is taken into the chamber in a moist state and brought into contact with the adsorbent material by the atmosphere, thereby performing the adsorption treatment. At the same time, a drying treatment is performed to dry the adsorbent material.

3. The atmospheric carbon dioxide separation and recovery equipment according to claim 1, wherein, The adsorption treatment time for using the adsorbent material to perform the adsorption treatment before taking it in and discharging it in the adsorption treatment chamber is more than twice the regeneration treatment time for regenerating the adsorbent material before taking it in and discharging it in the regeneration treatment chamber.

4. The atmospheric carbon dioxide separation and recovery equipment according to claim 1, wherein, The atmospheric carbon dioxide separation and recovery equipment has a temperature adjustment device that, during the regeneration process in the regeneration chamber, maintains or heats the regeneration chamber so that the internal temperature of the regeneration chamber reaches a specified value or higher.

5. The atmospheric carbon dioxide separation and recovery equipment according to claim 1, wherein, The adsorption treatment chamber includes: An inflow surface that allows atmospheric air to flow from the outside of the adsorption treatment chamber into its interior; and An outlet surface allows atmospheric air to flow out from the inside of the adsorption treatment chamber to the outside of the adsorption treatment chamber. The atmospheric carbon dioxide separation and recovery equipment has an attraction device located outside the adsorption treatment chamber. The attraction device attracts the atmosphere inside the adsorption treatment chamber through the outflow surface, thereby causing the atmosphere to flow from the outside of the adsorption treatment chamber into the interior of the adsorption treatment chamber through the inflow surface.

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