Adsorption system and adsorption method

Abstract

To provide an adsorption system and an adsorption method which can improve adsorption efficiency of a gas component.SOLUTION: An adsorption system 1 adsorbs a predetermined gas component, from a gas containing a predetermined gas component serving as an adsorption target, and water vapor. The adsorption system 1 includes: an adsorption part 13 for adsorbing the predetermined gas component from the gas; a measurement part 11 for measuring humidity of the gas; and a flow rate control part 12 for controlling the flow rate of the gas supplied to the adsorption part 13, on the basis of the humidity measured by the measurement part 11.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to adsorption systems and methods. [Background technology]

[0002] Patent Document 1 describes an air purification device for a vehicle that uses an adsorbent to adsorb carbon dioxide and water vapor inside the vehicle. The vehicle air purification device described in Patent Document 1 measures the concentrations of carbon dioxide and water vapor inside the vehicle and estimates whether the adsorbent is saturated based on the measured concentrations. If the vehicle air purification device described in Patent Document 1 estimates that the adsorption state of the adsorbent is saturated, it releases carbon dioxide and water vapor from the adsorbent. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-98874 Summary of the Invention [Problem to be solved by the invention]

[0004] As described in Patent Document 1, an adsorbent that adsorbs a predetermined gas component such as carbon dioxide adsorbs not only the predetermined gas component but also water vapor in the gas. When an adsorbent adsorbs water vapor, the amount of gases other than water vapor that the adsorbent can adsorb decreases. Therefore, in cases where adsorption of water vapor is not the objective, there has been a problem in that the adsorption efficiency of a specific gas component that is desired to be adsorbed decreases when the humidity in the gas is high.

[0005] In other words, the prior art has a problem in that when the humidity of the gas is high, the adsorption efficiency of the gas component that is desired to be adsorbed cannot be sufficiently improved. Patent Document 1 does not disclose any technology that can solve such problems.

[0006] The present disclosure has been made to solve such problems, and aims to provide an adsorption system and an adsorption method that can improve the adsorption efficiency of gas components. [Means for solving the problem]

[0007] An adsorption system according to one aspect of the present disclosure includes: An adsorption system that adsorbs a predetermined gas component from a gas containing the predetermined gas component to be adsorbed and water vapor, comprising: an adsorption unit that adsorbs the predetermined gas component from the gas; a measuring unit for measuring the humidity of the gas; a flow rate control unit that controls the flow rate of the gas being supplied to the adsorption unit based on the humidity measured by the measurement unit, It is an adsorption system.

[0008] With this configuration, the adsorption system according to an embodiment of the present disclosure can adjust the adsorption capacity for a predetermined gas component and water vapor, thereby improving the adsorption efficiency of the gas component.

[0009] In an adsorption system according to one embodiment of the present disclosure, the flow rate control unit may determine the flow rate of the gas to be a first flow rate when the humidity measured by the measurement unit is smaller than a predetermined threshold, and may determine the flow rate of the gas to be a second flow rate faster than the first flow rate when the humidity measured by the measurement unit is greater than a predetermined threshold. With this configuration, the adsorption system according to one aspect of the present disclosure can reduce the cost of adsorbing gas components.

[0010] The adsorption system according to one aspect of the present disclosure is particularly effective when the gas is atmospheric air and the predetermined gas component is carbon dioxide.

[0011] An adsorption method according to one aspect of the present disclosure includes: An adsorption method for adsorbing a predetermined gas component from a gas containing the predetermined gas component to be adsorbed and water vapor, comprising: measuring the humidity of the gas; controlling a flow rate of the gas being supplied to an adsorption unit that adsorbs the predetermined gas component from the gas based on the measured humidity; It is an adsorption method. [Effects of the Invention]

[0012] The present disclosure provides an adsorption system and an adsorption method that can improve the adsorption efficiency of gas components. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a block diagram showing a configuration of an adsorption system according to a first embodiment. [Figure 2] 10 is a flowchart showing the operation of the adsorption system according to the second embodiment. [Figure 3] 1 is a schematic cross-sectional view showing the configuration of an adsorption system according to a first embodiment. [Figure 4] 10 is a flowchart showing the operation of the adsorption system according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] (First embodiment) <Adsorption system configuration> Hereinafter, a first embodiment according to the present disclosure will be described in detail with reference to the drawings. First, the configuration of the adsorption system according to this embodiment will be described in detail. Fig. 1 is a block diagram showing the configuration of the adsorption system according to the first embodiment.

[0015] The adsorption system 1 according to the first embodiment is an adsorption system that adsorbs a predetermined gas component from a gas containing the predetermined gas component to be adsorbed and water vapor. The adsorption system 1 according to the first embodiment includes a measurement unit 11, a flow rate control unit 12, and an adsorption unit 13.

[0016] The adsorption system 1 may be, for example, a so-called direct air capture (DAC) system that adsorbs carbon dioxide contained in the atmosphere. The adsorption system 1 may also be an exhaust gas purification system that adsorbs nitrogen oxides, sulfur oxides, and the like contained in exhaust gases emitted from factories, automobiles, and the like. The adsorption system 1 may also adsorb a predetermined gas component contained in a gas, for example, to produce a high-purity predetermined gas component.

[0017] In other words, the adsorption system 1 may be used for any purpose as long as it has a configuration that adsorbs a predetermined gas component contained in a gas. Furthermore, the gas to which the adsorption system 1 is applied may be any gas as long as it contains water vapor and a predetermined gas component to be adsorbed. Furthermore, the predetermined gas component to be adsorbed by the adsorption system 1 according to the first embodiment may be any gas component as long as it is an adsorbable gas component.

[0018] The adsorption unit 13 adsorbs a predetermined gas component from the gas. The adsorption unit 13 has an adsorbent that adsorbs the predetermined gas component. The adsorption unit 13 causes the adsorbent to adsorb the predetermined gas component. For example, the adsorption unit 13 may include a filter having pore surfaces coated with an adsorbent as an adsorbent material. The adsorption unit 13 may then adsorb a predetermined gas component by supplying gas to the filter.

[0019] The adsorbent can be changed appropriately depending on the specific gas component to be adsorbed. For example, when the specified gas component is an acidic compound such as carbon dioxide, nitrogen oxides, or sulfur oxides, the adsorbent may be a honeycomb filter having a carrier carrying an adsorbent such as polyethyleneimine, primary amine, secondary amine, or secondary alkanolamine on its pore surface.

[0020] Here, the adsorption capacity of the adsorption unit 13 changes depending on the gas flow rate. More specifically, the adsorption capacity of the adsorption unit 13 changes for each gas component depending on the gas flow rate. Even more specifically, when the gas flow rate increases, the adsorption capacity of the adsorption unit 13 decreases more significantly for gas components with weaker affinity for the adsorbent.

[0021] Therefore, by controlling the flow rate of the gas supplied to the adsorption unit 13, the adsorption capacity of the adsorption unit 13 for each gas component can be controlled. For example, when the adsorption unit 13 adsorbs carbon dioxide and water vapor, if the flow rate control unit 12 increases the flow rate of the gas supplied to the adsorption unit 13, the amount of carbon dioxide adsorbed by the adsorption unit 13 increases and the amount of water vapor adsorbed decreases.

[0022] The measuring unit 11 measures the humidity of the gas and outputs the measured humidity of the gas to the flow rate control unit 12. More specifically, the measurement unit 11 measures the humidity of the gas before the flow rate is controlled by the flow rate control unit 12, which will be described later. The measurement unit 11 may also be configured to measure the humidity of gas that has never had a predetermined gas component adsorbed by the adsorption system 1. The humidity measured by the measuring unit 11 may be relative humidity or absolute humidity.

[0023] The flow rate control unit 12 acquires the humidity of the gas from the measurement unit 11 . The flow rate control unit 12 controls the flow rate of the gas being supplied to the adsorption unit 13 based on the humidity measured by the measurement unit 11 .

[0024] More specifically, flow rate control unit 12 determines the flow rate of the gas to be supplied to adsorption unit 13 based on the humidity measured by measurement unit 11. Then, flow rate control unit 12 controls the operation of a mechanism that supplies gas to adsorption unit 13 so that the determined flow rate is achieved.

[0025] The flow rate control unit 12 may, for example, input the measured humidity into a predetermined function to determine the flow rate of the gas. Furthermore, the flow rate control unit 12 may determine the flow rate of the gas by referring to a table that records the humidity ranges and the flow rates of the gas in association with each other. Furthermore, the flow rate control unit 12 may determine the flow rate of the gas using, for example, artificial intelligence (AI) that outputs the flow rate of the gas using humidity as input information.

[0026] In other words, the flow rate control unit 12 may use any method to determine the flow rate of the gas to be supplied to the adsorption unit 13, as long as it determines the flow rate of the gas to be supplied to the adsorption unit 13 based on the humidity measured by the measurement unit 11.

[0027] The flow rate control unit 12 determines the flow rate in a state where the atmosphere is supplied to at least the adsorption unit 13. In other words, the flow rate control unit 12 determines at least a flow rate that is greater than zero.

[0028] The flow rate control unit 12 may control the flow rate of the gas being supplied to the adsorption unit 13 by, for example, controlling the rotation speed of a fan that supplies the gas to the adsorption unit 13 . Furthermore, the flow rate control unit 12 may control the flow rate of the gas being supplied to the adsorption unit 13 by, for example, controlling the output amount of a pump that supplies the gas to the adsorption unit 13 .

[0029] That is, the flow rate control unit 12 may use any method to control the flow rate of the gas supplied to the adsorption unit 13 as long as the method can control the flow rate of the gas to the determined flow rate. Furthermore, the mechanism for supplying gas to the adsorption unit 13 may be any mechanism as long as it is capable of supplying gas to the adsorption unit 13 and changing the flow rate of the gas being supplied.

[0030] Here, an increase in the gas flow rate increases the operating cost of the mechanism that supplies the gas to the adsorption unit 13. On the other hand, if the adsorption capacity of the adsorption unit 13 for a predetermined gas component increases as the gas flow rate increases, the adsorption unit 13 can adsorb a larger amount of the predetermined gas component as the gas flow rate increases.

[0031] Therefore, the flow rate control unit 12 may control the flow rate of the gas further based on the operating cost of the mechanism that supplies the gas to the adsorption unit 13. For example, when the humidity measured by the measurement unit 11 is smaller than a predetermined threshold, the flow rate control unit 12 may determine the gas flow rate to be a first flow rate, and when the humidity measured by the measurement unit 11 is larger than the predetermined threshold, the flow rate control unit 12 may determine the gas flow rate to be a second flow rate that is faster than the first flow rate. With this configuration, the adsorption system 1 according to this embodiment can more efficiently adsorb the predetermined gas component.

[0032] <Adsorption system operation> Next, a detailed description will be given of the operation of the adsorption system, that is, the adsorption method according to the first embodiment. Fig. 2 is a flowchart showing the operation of the adsorption system according to the first embodiment.

[0033] First, the measurement unit 11 measures the humidity of the gas (step ST101). Next, the flow rate control unit 12 controls the flow rate of the gas being supplied to the adsorption unit 13 (step ST102). Finally, the adsorption unit 13 adsorbs the predetermined gas component from the gas, and the adsorption system 1 ends the series of operations (step ST103).

[0034] As described above, the adsorption system of this embodiment is an adsorption system that adsorbs a specific gas component from a gas containing the specific gas component to be adsorbed and water vapor, and controls the flow rate of the gas supplied to the adsorption section based on the humidity of the gas. With this configuration, the adsorption system according to an embodiment of the present disclosure can adjust the adsorption capacity for a predetermined gas component and water vapor, thereby improving the adsorption efficiency of the gas component.

[0035] (Second embodiment) <Adsorption system configuration> A second embodiment of the present disclosure will be described in detail below with reference to the drawings. The second embodiment is a specific example of the adsorption system according to the first embodiment. First, the configuration of the adsorption system according to this embodiment will be described in detail. Fig. 3 is a schematic cross-sectional view showing the configuration of the adsorption system according to the second embodiment.

[0036] The adsorption system 1 according to the second embodiment is a so-called direct air capture (DAC) system that adsorbs carbon dioxide contained in the atmosphere. The adsorption system 1 according to the second embodiment takes in the atmosphere using a fan F, supplies the taken-in atmosphere to an adsorption unit 13, and adsorbs carbon dioxide from the supplied atmosphere. The adsorption system 1 according to the second embodiment includes a measurement unit 11, a flow rate control unit 12, an adsorption unit 13, a fan F, flow paths R1 to R5, and adjustment valves V1 to V4.

[0037] The measurement unit 11 according to the second embodiment is a hygrometer provided near the intake port of the adsorption system 1. The measurement unit 11 outputs the measured humidity to the flow rate control unit 12. The air whose humidity has been measured by the measuring unit 11 is taken into the flow path R1 by the rotation of a fan F, which will be described later.

[0038] Flow path R1 is a so-called pipeline, which is the passage through which the air taken in by the adsorption system 1 first flows. An air intake port is provided at one end of flow path R1, and a fan F is provided at the other end. The air that has passed through flow path R1 is sent to flow path R2 via fan F.

[0039] The fan F corresponds to the mechanism that supplies gas to the adsorption unit 13 in the first embodiment. The fan F is a fan provided at the end of the flow path R1, and generates an airflow by rotating. The airflow generated by the fan F takes in air from an intake port and supplies it to the adsorption unit 13.

[0040] The rotation speed of the fan F is controlled by a flow rate control unit 12. The greater the rotation rate of the fan F, the greater the flow rate of the air supplied to the adsorption unit 13. On the other hand, the greater the rotation rate of the fan F, the greater the operating cost of the fan F. The air that has passed through the fan F is sent to the flow path R2.

[0041] The flow rate control unit 12 acquires the atmospheric humidity measured by the measurement unit 11. The flow rate control unit 12 determines the flow rate of the air being supplied to the adsorption unit 13 based on the obtained humidity of the air. The flow rate control unit 12 controls the rotation rate of the fan F so that the flow rate of the air being supplied to the adsorption unit 13 becomes the determined flow rate.

[0042] The flow rate control unit 12 may be configured as a control computer for the fan F. The flow rate control unit 12 may also be configured as a control computer for the adsorption system 1. In this case, the flow rate control unit 12 may include an arithmetic unit such as a CPU (Central Processing Unit) not shown, and a memory unit such as a RAM (Random Access Memory) or a ROM (Read Only Memory) that stores programs and data for controlling the operation of the flow rate control unit 12.

[0043] The flow rate control unit 12 according to this embodiment determines whether the humidity acquired from the measurement unit 11 is smaller than a predetermined threshold value. When the acquired humidity is smaller than a predetermined threshold, the flow rate control unit 12 determines the flow rate of the gas to be a first flow rate. When the humidity measured by the measurement unit is larger than a predetermined threshold, the flow rate control unit 12 determines the flow rate of the gas to be a second flow rate that is faster than the first flow rate. That is, the flow rate control unit 12 slows down the flow rate of the air when the amount of water vapor contained in the air is small, and speeds up the flow rate of the air when the amount of water vapor contained in the air is large.

[0044] When the amount of water vapor contained in the atmosphere is large, the adsorption section 13 tends to adsorb water vapor, and accordingly tends to adsorb carbon dioxide less easily. Therefore, when the amount of water vapor contained in the atmosphere is large, the flow rate control unit 12 increases the flow rate of the atmosphere to increase the adsorption capacity of the adsorption unit 13 for carbon dioxide. With this configuration, the adsorption system 1 according to this embodiment can efficiently adsorb carbon dioxide even when the amount of water vapor contained in the atmosphere is large.

[0045] On the other hand, when the amount of water vapor contained in the atmosphere is small, the adsorption section 13 has difficulty adsorbing water vapor, and therefore can efficiently adsorb carbon dioxide even when the flow rate of the atmosphere is slow. Therefore, when the amount of water vapor contained in the air is small, the flow rate control unit 12 reduces the flow rate of the air to reduce the operating cost of the fan F. With this configuration, the adsorption system 1 according to this embodiment can reduce the cost of adsorbing carbon dioxide.

[0046] The adsorption unit 13 is supplied with air via the flow path R2. More specifically, the adsorption unit 13 is supplied with air, the flow rate of which is controlled by the flow rate control unit 12, via the flow path R2. The adsorption section 13 adsorbs carbon dioxide contained in the supplied air. The configuration of the suction unit 13 will be described in more detail below.

[0047] The adsorption unit 13 according to this embodiment includes two adsorption tanks 131 each having an adsorption layer 132 that adsorbs carbon dioxide. The adsorption unit 13 performs an adsorption process of carbon dioxide using one of the adsorption tanks 131. Then, while one of the adsorption tanks 131 is adsorbing carbon dioxide, the adsorption unit 13 performs a desorption process of the carbon dioxide adsorbed in the other adsorption tank.

[0048] When the carbon dioxide adsorption process performed in one of the adsorption tanks 131 and the carbon dioxide desorption process performed in the other adsorption tank are completed, the adsorption section 13 switches the roles of the two adsorption tanks 131 and performs the carbon dioxide adsorption and desorption processes again.

[0049] The adsorption tank 131 contains an adsorption layer 132. The adsorption tank 131 is connected to the flow paths R2 to R5 via the regulating valves V1 to V4, respectively. When performing carbon dioxide adsorption processing, atmospheric air is supplied via flow path R2 to the adsorption tank 131. More specifically, atmospheric air, the flow rate of which is controlled by flow rate control unit 12, is supplied to the adsorption tank 131 from flow path R2.

[0050] The adsorption tank 131 then discharges the air from which carbon dioxide has been adsorbed and removed via flow path R4 to the outside of the adsorption system 1. The adsorption tank 131 may also release the air from which carbon dioxide has been adsorbed and removed, for example, outdoors.

[0051] When carbon dioxide desorption is performed, the adsorption tank 131 is supplied with desorbed gas via flow path R3. The adsorption tank 131 then discharges the carbon dioxide desorbed by the desorbed gas to the outside of the adsorption system 1 via flow path R5. The adsorption tank 131 may discharge the desorbed carbon dioxide, for example, to a storage container.

[0052] The adsorption layer 132 is a layer that adsorbs carbon dioxide and is provided inside the adsorption tank 131. The adsorption layer 132 according to this embodiment is a honeycomb filter coated with silica that supports polyethyleneimine.

[0053] Flow path R2 is a flow path through which air flows, the flow rate of which is controlled by flow rate control unit 12, and is connected to adsorption tank 131 via adjustment valve V1. Flow path R2 has a branched structure for connecting to two adsorption tanks 131.

[0054] The regulating valve V1 connects the flow path R2 and the adsorption tank 131. The regulating valve V1 can block the air supplied to the adsorption tank 131 from the flow path R2. When the adsorption tank 131 is performing an adsorption process, the adjustment valve V1 does not block the air supplied to the adsorption tank 131. On the other hand, when the adsorption tank 131 is performing a desorption process, the adjustment valve V1 blocks the air supplied to the adsorption tank 131.

[0055] Flow path R4 is a flow path through which the air flows after carbon dioxide has been adsorbed and removed by the adsorption layer 132. The air flowing through flow path R4 is discharged to the outside of the adsorption system 1. Flow path R4 is connected to the adsorption tank 131 via a regulating valve V4. The regulating valve V4 connects the flow path R4 to the adsorption tank 131. The regulating valve V4 can block gas being released to the outside of the adsorption system 1 via the flow path R4.

[0056] When the adsorption tank 131 is performing an adsorption process, the regulating valve V4 does not block the gas being released to the outside of the adsorption system 1. On the other hand, when the adsorption tank 131 is performing a desorption process, the regulating valve V4 blocks the gas being released to the outside of the adsorption system 1.

[0057] The flow path R3 is a flow path through which the desorbed gas supplied to the adsorption tank flows. The flow path R3 is connected to the adsorption tank 131 via an adjustment valve V2. The regulating valve V2 connects the flow path R3 and the adsorption tank 131. The regulating valve V2 can block the desorbed gas supplied to the adsorption tank 131 via the flow path R3.

[0058] When the adsorption tank 131 is performing an adsorption process, the adjustment valve V2 blocks the desorption gas supplied to the adsorption tank 131. On the other hand, when the adsorption tank 131 is performing a desorption process, the adjustment valve V2 does not block the desorption gas supplied to the adsorption tank 131.

[0059] Flow path R5 is a flow path through which carbon dioxide desorbed from the adsorption layer 132 flows. The carbon dioxide desorbed from the adsorption layer 132 is released through flow path R5 to the outside of the adsorption system 1. Flow path R5 is connected to the adsorption tank 131 via an adjustment valve V3. The regulating valve V3 connects the flow path R5 and the adsorption tank 131. The regulating valve V3 can block carbon dioxide from being released to the outside of the adsorption system 1 via the flow path R5.

[0060] When the adsorption tank 131 is performing an adsorption process, the regulating valve V3 blocks carbon dioxide from being released outside the adsorption system 1. On the other hand, when the adsorption tank 131 is performing a desorption process, the regulating valve V3 does not block carbon dioxide from being released outside the adsorption system 1.

[0061] <Adsorption system operation> Next, the operation of the adsorption system according to the second embodiment, that is, the adsorption method according to the second embodiment, will be described in detail. Fig. 4 is a flowchart showing the operation of the adsorption system according to the second embodiment.

[0062] First, the measurement unit 11 measures the humidity of the atmosphere (step ST201). More specifically, the measurement unit 11 measures the humidity of the atmosphere taken in through the intake port. Next, the flow velocity control unit 12 determines whether the humidity of the atmosphere is lower than a predetermined threshold value (step ST202).

[0063] If the humidity of the atmosphere is lower than the predetermined threshold value (YES in step ST202), the flow rate control unit 12 determines the flow rate of the atmosphere to be the first flow rate (step ST203). On the other hand, if the humidity of the atmosphere is higher than the predetermined threshold value (NO in step ST202), the flow rate control unit 12 determines the flow rate of the atmosphere to be the second flow rate (step ST204). However, the second flow rate is faster than the first flow rate.

[0064] In other words, steps ST202 to ST204 are steps in which the flow rate control unit 12 determines the flow rate of the atmosphere to be slow when the humidity of the atmosphere is lower than a predetermined threshold, and determines the flow rate of the atmosphere to be fast when the humidity of the atmosphere is higher than the predetermined threshold.

[0065] Next, the flow rate control unit 12 controls the rotation rate of the fan so that the flow rate of the air becomes the determined flow rate (step ST205). Finally, the adsorption unit 13 adsorbs carbon dioxide from the supplied air (step ST206), and the series of operations of the adsorption system 1 is completed. More specifically, the adsorption unit 13 adsorbs carbon dioxide from the air whose flow rate has been controlled, and the series of operations of the adsorption system 1 is completed.

[0066] As described above, the adsorption system 1 according to this embodiment is a direct air capture (DAC) system that adsorbs carbon dioxide contained in the atmosphere. The adsorption system 1 of this embodiment supplies air to the adsorption unit at a high flow rate when the humidity of the air is greater than a predetermined threshold, and supplies air to the adsorption unit at a low flow rate when the humidity of the air is less than the predetermined threshold.

[0067] With this configuration, the adsorption system 1 can improve its ability to adsorb carbon dioxide when the humidity of the atmosphere is higher than a predetermined threshold, that is, when the adsorption system 1 has difficulty adsorbing carbon dioxide. Furthermore, with this configuration, the adsorption system 1 can reduce the cost of adsorbing carbon dioxide when the humidity of the atmosphere is lower than a predetermined threshold, that is, in a situation where the adsorption system 1 can easily adsorb carbon dioxide. As a result, the adsorption system 1 according to this embodiment can improve the carbon dioxide adsorption efficiency. [Example]

[0068] Hereinafter, the present disclosure will be described more specifically based on examples and comparative examples, but the present disclosure is not limited to these examples.

[0069] <Creating an adsorption layer> A cordierite substrate using a honeycomb (φ: 8 mm × 50 mm) manufactured by NGK Insulators, Ltd. was coated with a coating liquid made by mixing silica (average particle size: 10 μm) manufactured by Fuji Silysia Chemical Ltd. and a binder, and then dried. Polyethyleneimine (average molecular weight: 600) manufactured by Fujifilm Wako Co., Ltd. was diluted with ethanol to a concentration of 30% by mass to prepare an amine solution. The substrate coated with the coating liquid was immersed in an amine solution overnight, and then the substrate was dried under reduced pressure to form an adsorption layer.

[0070] <Adsorption test> [Example 1] Air at a temperature of 25°C and a relative humidity of 90% was blown onto the adsorption layer to adsorb carbon dioxide and water vapor. Thereafter, the adsorption layer was heated to 100° C., and nitrogen gas was blown onto it to desorb the adsorbed carbon dioxide and water vapor. The amounts of carbon dioxide and water vapor desorbed were then measured. Based on the measured amounts of carbon dioxide and water vapor, the carbon dioxide recovery energy and the molar ratio of adsorbed carbon dioxide molecules to adsorbed water molecules were calculated.

[0071] [Comparative Example 1] Air at a wind speed of 1.0 m / s, 25°C, and a relative humidity of 90% was blown onto the prepared adsorption layer to adsorb carbon dioxide and water vapor. Thereafter, the adsorption layer was heated to 100° C., and nitrogen gas was blown onto it to desorb the adsorbed carbon dioxide and water vapor. The amounts of carbon dioxide and water vapor desorbed were then measured. Based on the measured amounts of carbon dioxide and water vapor, the carbon dioxide recovery energy and the molar ratio of adsorbed carbon dioxide molecules to adsorbed water molecules were calculated.

[0072] [Test Results] Table 1 shows the results of the adsorption test. The measured amounts of carbon dioxide and water vapor are shown as the number of moles adsorbed by silica and polyethyleneimine per gram. Additionally, carbon dioxide capture energy is listed as the energy required to capture one ton of carbon dioxide.

[0073] [Table 1]

[0074] According to Table 1, the adsorption layer in the example adsorbs a larger amount of carbon dioxide and a smaller amount of water vapor than the adsorption layer in the comparative example. In other words, Table 1 makes it clear that the adsorption capacity of the adsorption layer for each gas can be controlled by controlling the flow rate of the air.

[0075] Furthermore, according to Table 1, the adsorption layer in the example requires less energy to adsorb a unit amount of carbon dioxide than the adsorption layer in the comparative example. In other words, Table 1 reveals that the adsorption layer in the example can capture carbon dioxide more efficiently than the adsorption layer in the comparative example.

[0076] The present invention has been described above in accordance with the above-described embodiments, but the present invention is not limited to the configurations of the above-described embodiments, and naturally includes various modifications, alterations, and combinations that can be made by a person skilled in the art within the scope of the invention claimed in the claims of this application. [Explanation of symbols]

[0077] 1. Adsorption system 11 Measuring part 12 Flow velocity control section 13 Adsorption part F Fan

Claims

1. An adsorption system for adsorbing carbon dioxide from a gas containing carbon dioxide and water vapor, comprising: an adsorption unit that adsorbs the carbon dioxide from the gas using polyethyleneimine as an adsorbent; a measuring unit for measuring the humidity of the gas; a flow rate control unit that controls a flow rate of the gas being supplied to the adsorption unit based on the humidity measured by the measurement unit, the flow rate control unit determines the flow rate of the gas to be a first flow rate when the humidity measured by the measurement unit is smaller than a predetermined threshold, and determines the flow rate of the gas to be a second flow rate faster than the first flow rate when the humidity measured by the measurement unit is larger than a predetermined threshold, the predetermined threshold is determined depending on the ease with which the adsorption unit adsorbs the carbon dioxide, and when the humidity is greater than the predetermined threshold, the adsorption unit is less likely to adsorb the carbon dioxide than when the humidity is less than the predetermined threshold. Adsorption system.

2. An adsorption method for adsorbing carbon dioxide from a gas containing carbon dioxide and water vapor, comprising: measuring the humidity of the gas; based on the measured humidity, controlling a flow rate of the gas being supplied to an adsorption section that adsorbs the carbon dioxide from the gas using polyethyleneimine as an adsorbent; When controlling the flow rate of the gas, If the measured humidity is smaller than a predetermined threshold, the flow rate of the gas is determined to be a first flow rate, and if the measured humidity is greater than a predetermined threshold, the flow rate of the gas is determined to be a second flow rate that is faster than the first flow rate; the predetermined threshold is determined depending on the ease with which the adsorption unit adsorbs the carbon dioxide, and when the humidity is greater than the predetermined threshold, the adsorption unit is less likely to adsorb the carbon dioxide than when the humidity is less than the predetermined threshold. Adsorption method.

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