Carbon dioxide recovery device

Abstract

To join a plurality of adsorbent units easily.SOLUTION: A carbon dioxide recovery system includes: adsorbent units 10 each including a solid adsorbent 60 therein; and a fan unit 20 having a fan for generating airflow flowing toward the adsorbent units 10. The adsorbent unit 10 has: a positioning unit 30 which is provided on one surface of the adsorbent unit 10 and to which another adsorbent unit 10 may be attached; and a fitted part 40 which is provided on the other surface of the adsorbent unit 10 and in which the positioning unit 30 of the other adsorbent unit 10 may be fitted. The fan unit 20 has a fitting part 31 which may fit in the fitted part 40.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a carbon dioxide capture device. [Background technology]

[0002] Efforts are being made on a global scale to reduce carbon dioxide emissions in order to achieve carbon neutrality by 2050. In addition, negative emissions efforts to actively capture carbon dioxide are also being promoted, and efforts are being made to capture and utilize carbon dioxide from facilities that emit large amounts of carbon dioxide, such as power plants and steelworks.

[0003] Methods for recovering carbon dioxide from facilities such as power plants and steelworks involve placing an adsorption tower containing a liquid adsorbent such as amine or a solid adsorbent such as zeolite in the combustion exhaust gas transport line, passing the combustion exhaust gas through the adsorption tower, and adsorbing the carbon dioxide onto the adsorbent as it passes through.

[0004] In addition, the carbon dioxide adsorbed in the solid adsorbent such as zeolite is desorbed from the adsorbent by reducing the pressure inside the adsorption tower with a vacuum pump, and is supplied from the release line to the carbon dioxide circulation line and recovered in a tank. By desorbing the carbon dioxide in this way, the adsorbent is regenerated to a state where it can adsorb carbon dioxide again.

[0005] The carbon dioxide adsorbed in a liquid adsorbent such as an amine is heated with water vapor or the like to release the carbon dioxide from the adsorbent, and the released carbon dioxide is then collected.

[0006] The "Carbon Dioxide Capture System" disclosed in Patent Document 1 proposes a suitcase-sized personal carbon dioxide capture device. The system uses electricity obtained from solar panels to electrolyze a sodium chloride solution to generate sodium hydroxide, and then adsorbs carbon dioxide in the air and indoors to the sodium hydroxide. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2019-181451 A Summary of the Invention [Problem to be solved by the invention]

[0008] Conventional carbon dioxide capture systems are designed for facilities that emit large amounts of carbon dioxide, such as power plants and steelworks, and are large-scale systems that use adsorption towers. These capture systems require energy for heating and decompression, and there is a risk of emitting additional carbon dioxide.

[0009] In addition, conventional capture systems were designed to reduce emissions from facilities that emit large amounts of carbon dioxide, such as power plants and steelworks, and did not allow ordinary individuals to actively participate in global warming countermeasures such as reducing carbon dioxide emissions.

[0010] The "carbon dioxide capture system" disclosed in Patent Document 1 is proposed as a small-scale, personal system. However, sodium hydroxide is used as the adsorbent, and there are safety concerns for personal use.

[0011] In addition, for small-scale / personal use, it is expected that the system will be able to easily handle adsorbents, etc. [Means for solving the problem]

[0012] In view of the above, the carbon dioxide capture device according to the present invention is an adsorbent unit including a solid adsorbent therein; a fan unit having a fan for generating an airflow to the adsorbent unit; Equipped with the adsorbent unit has a positioning portion provided on one surface of the adsorbent unit, to which another adsorbent unit can be attached, and a fitting portion provided on the other surface of the adsorbent unit, into which the positioning portion of the other adsorbent unit can be fitted, The fan unit has a fitting portion that can be fitted into the fitted portion. Effect of the Invention

[0013] According to the present invention, by utilizing the positioning mechanism used when attaching the adsorbent unit to the fan, it becomes possible to easily combine a plurality of adsorbent units. [Brief description of the drawings]

[0014] [Figure 1] FIG. 2 is a partially exploded perspective view of the carbon dioxide capture device of the present invention. [Diagram 2] FIG. 2 is a schematic diagram showing a cross section of the carbon dioxide capture device of FIG. [Diagram 3] FIG. 2 is a schematic diagram showing a cross section of an adsorbent unit of the present invention. [Figure 4] FIG. 2 is a schematic diagram showing a state in which the adsorbent units of the present invention are stacked. [Diagram 5] FIG. 1 is a diagram showing a state in which adsorbent units of the present invention are stacked and hot air and water vapor are passed through the adsorbent to desorb and capture carbon dioxide. [Figure 6] FIG. 13 is a diagram showing changes in carbon dioxide concentration due to differences in carbon dioxide adsorbents. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] A preferred embodiment of the present invention will be described in detail below. As shown in the partially exploded perspective view of Fig. 1, the carbon dioxide capture device of the present invention is configured to include an adsorbent unit 10 that contains a solid adsorbent 60 (see Fig. 2) that adsorbs carbon dioxide, and a fan 20 that generates an airflow toward the adsorbent unit. Although the adsorbent unit 10 can adsorb carbon dioxide by itself, by combining the adsorbent unit 10 with the fan 20, an airflow toward the solid adsorbent 60 can be generated, improving the adsorption efficiency.

[0016] A fan mounting plate 72 and an adsorbent unit mounting plate 71 are provided on a base 70 of the carbon dioxide capture device. A fan 20 is installed on the surface of the fan mounting plate 72 facing the adsorbent unit so that an airflow is generated from the fan 20 side to the adsorbent unit side.

[0017] A cross-sectional view of the carbon dioxide capture device according to this embodiment is shown in Figure 2. A positioning pin 31 is provided on the surface of the adsorbent unit mounting plate 71 opposite the fan 20, and a positioning hole 40 provided in the adsorbent unit 10 fits into this positioning pin, allowing the adsorbent unit 10 to be positioned directly opposite the fan 20 and to be mounted in a position that is effective for the airflow generated by the fan 20.

[0018] In this embodiment, the adsorbent unit 10 is shown in a state where two adsorbent units 10 are attached. The adsorbent unit 10 has a positioning pin 30 on the surface opposite to the surface on which the positioning hole 40 is provided, and the structure makes it easy to stack the adsorbent units 10 by the positioning mechanism consisting of the positioning pin 30 and the positioning hole 40, and it is not necessarily necessary to adsorb carbon dioxide with one adsorbent unit for the fan 20, but multiple adsorbent units can be stacked to adsorb carbon dioxide simultaneously.

[0019] In this embodiment, the fan 20 is attached to the fan mounting plate 72, and the adsorbent unit 10 is attached to the adsorbent unit mounting plate 71, and are configured as separate entities, but it is also possible to provide a positioning pin on the frame of the fan and attach the adsorbent unit so that the positioning hole fits into the pin, forming an integrated configuration.

[0020] Alternatively, the fan and power supply unit may be housed in a single box, a positioning pin may be provided on the box, and the adsorbent unit may be attached to the positioning pin.

[0021] Further, in this embodiment, the fan and the adsorbent unit are adjacent to each other, but they do not necessarily have to be adjacent to each other.

[0022] Furthermore, the fan does not necessarily have to be a dedicated fan for the adsorbent unit, and is not particularly limited as long as it generates an airflow to the adsorbent unit. For example, the fan can be applied to cooling fans used in personal computers, circulators that circulate air in rooms, electric fans, air conditioners, ventilation fans, and fans for blowing air inside automobiles. The adsorbent unit can be attached by providing a positioning mechanism, such as a positioning pin 31 that fits into a positioning hole 40 provided in the adsorbent unit 10, on the fan cover or outlet of these fans. By using these airflows, it becomes possible to efficiently adsorb carbon dioxide without using new energy for carbon dioxide adsorption.

[0023] In this embodiment, the positioning pins 30, 31 and the positioning holes 40 that fit therein are used as the positioning mechanism, but the positioning mechanism is not limited to this. For example, it is also possible to use at least a part of the outer frame of the adsorbent unit as the positioning mechanism.

[0024] In this embodiment, the fan 20 generates an airflow toward the adsorbent unit 10 side, but the fan 20 may be oriented so that the airflow is generated from the adsorbent unit 10 side toward the fan 20 side.

[0025] In this embodiment, a DC power source for driving the fan is supplied from a power source 50 such as a rechargeable battery, and the fan 20 is rotated to generate an airflow. This eliminates power source restrictions and allows the carbon dioxide capture device to be moved to any location. Of course, DC power may also be supplied from a 100V AC power source via a converter.

[0026] Fig. 3 is a schematic diagram of the cross section of an adsorbent unit of the present invention. The adsorbent unit 10 is constructed by filling a porous solid adsorbent 60 carrying an amine in a gas-permeable container. The shape of the container is not particularly limited, but a thin disk or plate shape is preferable, and this shape makes it possible to increase the ratio of the adsorbent area to the volume of the solid adsorbent.

[0027] As described above, in this embodiment, the adsorbent unit 10 is characterized in that a positioning pin 30 is provided on one surface, and a positioning hole 40 into which the positioning pin 31 fits is provided on the other surface of the adsorbent unit 10. That is, in the present invention, it is sufficient that a positioning portion is provided on one surface of the adsorbent unit 10, and a fitted portion that fits with the positioning portion is provided on the other surface.

[0028] This makes it possible to easily mount the adsorbent unit 10 at a position where the effect of the airflow generated by the fan is greatest, as shown in Figs.

[0029] With this configuration, the adsorbent units 10 can be easily stacked together by fitting them together using the positioning pins 30 and the positioning holes 40, as shown in Figure 4. This allows airflow to pass through multiple adsorbent units simultaneously to adsorb carbon dioxide.

[0030] There are no particular limitations on the material of the adsorbent unit 10 as long as it is breathable and has heat resistance capable of withstanding the temperature of the hot air and water vapor during carbon dioxide desorption. Metals such as aluminum and stainless steel, and engineering plastics that have heat resistance at or above the desorption temperature can be used.

[0031] The adsorbent unit 10 can adsorb carbon dioxide even when used alone. It can be used like a household deodorant or air freshener. By placing it on a table in an office or conference room where the carbon dioxide concentration is likely to be high, it can adsorb carbon dioxide more efficiently than by adsorbing it from the outside air.

[0032] It is also possible to install the device in places where carbon dioxide concentrations are high, such as the exhaust of small boilers or simple boilers, the outlets of stoves and fan heaters, and kitchens with gas stoves, to adsorb and capture carbon dioxide.

[0033] The solid adsorbent is preferably a porous material, and ceramic materials such as silica, alumina, titania, zirconia, magnesia, and zeolite, as well as activated carbon, porous carbon, and the like, can be used alone or in mixtures thereof.

[0034] The shape of the solid adsorbent is not particularly limited, but granular, pellet, and other shapes can be used.

[0035] The particle size of the solid adsorbent is 0.5 to 10 mm, more preferably 1 to 5 mm. If the particle size of the solid adsorbent is smaller than this range, it becomes difficult to hold the solid adsorbent while ensuring breathability, and in addition, the filling rate increases, resulting in poor breathability. If the particle size is larger than this range, the filling rate decreases, the amount of solid adsorbent decreases, and the adsorption capacity decreases. The filling rate is 20 to 80%, more preferably 40 to 70%. The higher the filling rate, the greater the amount of carbon dioxide adsorption, but if the filling rate is 80% or more, the breathability decreases, which impairs the air circulation during carbon dioxide adsorption and the circulation of hot air and water vapor during carbon dioxide desorption, resulting in poor adsorption and desorption efficiency.

[0036] Although a porous body alone can be used as a solid adsorbent, it is preferable to support an amine on a porous body, since this increases the amount of carbon dioxide adsorbed per unit weight of the adsorbent. In a porous body alone, carbon dioxide adsorption occurs by physical adsorption, and since the energy of adsorption and desorption is relatively small, the adsorption and desorption speed is fast, but the amount of carbon dioxide adsorbed tends to be small. On the other hand, adsorption by an amine is chemical adsorption, which requires a large energy during carbon dioxide adsorption and desorption, and the adsorption and desorption speed is slow, but the amount of carbon dioxide adsorbed tends to be large.

[0037] The amine-supported solid adsorbent preferably has an amine support amount of 3 to 50 wt%, more preferably 5 to 30 wt%. The larger the amine support amount, the greater the amount of amine adsorption, but the pores of the porous body are filled up, resulting in the porous body losing its physical adsorption ability.

[0038] The amine to be supported can be at least one selected from the group consisting of alkanolamines and polyamines, and mixtures thereof. Examples of the amine compound of the alkanolamines include monoethanolamine, diethanolamine, and triethanolamine. Examples of the amine compound of the polyamines include polyethyleneimine, ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and pentaethylenehexamine.

[0039] Regarding the desorption and capture of carbon dioxide, the adsorbent units that adsorbed carbon dioxide are collected and heated to desorb and capture the carbon dioxide. In general, the adsorbent units are arranged in a heatable furnace, and heat is applied from the outside to heat the solid adsorbent above the carbon dioxide desorption temperature, thereby desorbing and capturing the carbon dioxide.

[0040] In this embodiment, by utilizing a positioning mechanism, it is possible to easily stack the adsorbent units without misalignment in the thickness direction as shown in Fig. 4. Then, as shown in Fig. 5, a heating medium such as hot air or steam can be directly flowed into and heated in the portion filled with solid adsorbent 60 of the stacked adsorbent units 10, making it possible to efficiently desorb and capture carbon dioxide.

[0041] Example 1 Hereinafter, a carbon dioxide capture device configured with an adsorbent unit and a fan combined therewith will be described as an embodiment, but the present invention is not limited to these embodiments.

[0042] The carbon dioxide capture device of the present invention is evaluated by giving specific examples and comparative examples. The adsorbent unit is made of a ring-shaped aluminum alloy (A5052) housing with stainless steel (SUS304) wire mesh on both sides to hold the adsorbent while ensuring breathability. The adsorbent is filled into the adsorbent unit to achieve a filling rate of 70%.

[0043] The adsorbent was prepared by using activated spherical alumina (Sumitomo Chemical's NKHO-24, particle size 2-4 mm) as a porous material, supporting diethanolamine (DEA) at a ratio of 20 wt%, and then drying.

[0044] The fan used was the Timely USB fan BIGFAN120U (1900 rpm, 69 cfm).

[0045] The carbon dioxide capture device of the present invention was installed in a closed cubic space with sides of 40 cm, and the fan was driven by a mobile battery. After that, in this closed space, dilute sulfuric acid and sodium hydrogen carbonate were reacted to generate carbon dioxide to a concentration of 5000 ppm, which was then adsorbed by the adsorbent unit of this embodiment, and the change in concentration was measured, to perform a carbon dioxide adsorption test.

[0046] Comparative Example 1 A carbon dioxide capture device was produced and a carbon dioxide adsorption test was carried out in the same manner as in Example 1. However, activated spherical alumina (NKHO-24, manufactured by Sumitomo Chemical, particle size 2 to 4 mm) was used as the adsorbent.

[0047] [Comparison of carbon dioxide concentration changes] As in Example 1 and Comparative Example 1, carbon dioxide was adsorbed onto the adsorbent, and the change in concentration was measured. The results are shown in FIG.

[0048] It is clear that the carbon dioxide capture device of the present invention is capable of adsorbing carbon dioxide. It is also clear that the adsorption capacity of Example 1 is superior to that of Comparative Example 1. [Explanation of symbols]

[0049] 10 Adsorbent unit 20 Fans 30 Positioning pin 31 Positioning pin on fan mounting plate 40 Positioning hole 50 power supply 60 Solid adsorbent 70 Foundations 71 Adsorbent unit mounting plate 72 Fan mounting plate

Claims

1. an adsorbent unit including a solid adsorbent therein; a fan unit having a fan for generating an airflow to the adsorbent unit; Equipped with the adsorbent unit has a positioning portion provided on one surface of the adsorbent unit, to which another adsorbent unit can be attached, and a fitting portion provided on the other surface of the adsorbent unit, into which the positioning portion of the other adsorbent unit can be fitted, The carbon dioxide capture device according to claim 1, wherein the fan unit has a fitting portion that can be fitted into the fitted portion.

2. The carbon dioxide capture device according to claim 1 , wherein the positioning portion and the fitted portion are provided at positions that overlap when viewed from a direction perpendicular to the one surface.

3. 3. The carbon dioxide recovery apparatus according to claim 1, wherein the solid adsorbent is a porous material carrying an amine, and the amount of the amine carried is 3 to 50 wt %.

4. 4. The carbon dioxide recovery apparatus according to claim 3, wherein the amount of the amine supported is 5 to 30 wt %.

5. 3. The carbon dioxide recovery device according to claim 1, wherein the solid adsorbent is a porous material carrying an amine, and has a particle size of 0.5 to 10 mm.

6. The carbon dioxide recovery device according to claim 5, characterized in that the particle size is 1 to 5 mm.

7. 3. The carbon dioxide recovery apparatus according to claim 1, wherein the solid adsorbent is a porous body carrying an amine, and the filling rate of the solid adsorbent unit is 20 to 80%.

8. The carbon dioxide recovery device according to claim 7, characterized in that the filling rate is 40 to 70%.

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