JP2007203215A - Adsorption system of carbon dioxide and desorption-recovery system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel system efficiently separating carbon dioxide, which is one of causative substances of the global warming phenomenon, by adsorption effectively utilizing an inexpensive substance dispensing with a special route for obtaining or a substance capable of becoming an industrial waste, further the system being capable of ultimately efficiently reducing the amount of emission of carbon dioxide without carelessly leaking the desorbed carbon dioxide out of the system. <P>SOLUTION: The system is characterized by emitting a gas reduced to a decreased concentration of carbon dioxide from a gas discharging opening by introducing a gas containing carbon dioxide to a gas supplying opening for selectively adsorbing the carbon dioxide to an adsorbent in an adsorption container having the gas supplying opening, the gas discharging opening and a form of a cylinder or a rectangular solid, and filled with a filler comprising an essential component of at least one inorganic powder constituent selected from the group consisting of a bauxite powder, a dried powder of a precipitate by-produced by the Bayer process and a porous powder whose pH of the clear supernatant liquid of its suspension is not lower than 7. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a carbon dioxide adsorption system that contributes to the suppression of the global warming phenomenon, and its desorption / recovery system. More specifically, the present invention relates to an inexpensive substance that does not require a special acquisition route or a substance that can be industrial waste. Utilizing effectively, carbon dioxide, which is one of the causative substances of global warming phenomenon, is efficiently adsorbed and separated, and further, the desorbed carbon dioxide is recovered without inadvertently discharging out of the system, The present invention relates to a carbon dioxide adsorption system and a carbon dioxide desorption / recovery system that can ultimately reduce carbon dioxide emissions efficiently.

  Deterring global warming is now an important issue that should be implemented on a global scale. Under such circumstances, a technical method for suppressing the release of carbon dioxide, which is said to be a main causative substance of the greenhouse effect in the global warming phenomenon, has attracted attention. Conventionally, various new means are conceivable as such methods, and methods for utilizing the prior art have been proposed. These are broadly divided into three categories: biological approaches, chemical approaches, and physical approaches.

  Here, as a biological approach, for example, carbon dioxide is ingested by microorganisms to biosynthesize organic compounds such as biodegradable plastics. In addition, as a chemical approach, chemical measures are taken in which carbon dioxide is reacted with another substance to convert it into another compound.

  Furthermore, as a physical approach, for example, a method of adsorbing and separating carbon dioxide can be applied. By the way, a method for purifying hydrocarbons and carbon monoxide from exhaust gas by incorporating a sheet using ceramics having adsorption performance in order to prevent air pollution into the interior of an automobile engine room has been proposed as an adsorption separation method. Yes. Also, a method for purifying air or synthesis gas containing carbon dioxide as an impurity, a process of adsorbing carbon dioxide on an adsorbent comprising specific activated alumina (for example, see Patent Document 1), for purifying indoor air A carbon dioxide adsorbent having a specific composition that achieves both adsorption performance and desorption performance to be used, a carbon dioxide removal device using the same (for example, see Patent Document 2), and the like are disclosed.

However, the biological and chemical approaches described above require enormous amounts of energy for conversion to other organic compounds and for the production of substances that are reactive to carbon dioxide. From a point of view as a whole, it was a method that would not be a solution to the essential problem in that it would actually increase carbon dioxide emissions.
In the above physical approach, it is necessary to devise the selection of the adsorbent for the separation of carbon dioxide in the exhaust gas, and the purpose of use is the process air purification process or the indoor air purification. Therefore, in the point that the desorbed carbon dioxide is finally released out of the system, it is a method that does not become a solution to an essential problem regarding the suppression of the global warming phenomenon.

  Under the circumstances described above, it is important to consider the balance of carbon dioxide as a whole from the energy point of view, and the carbon dioxide in the gas is efficiently adsorbed and separated, and the desorbed carbon dioxide is not prepared. Therefore, there is a need for a system that can be recovered without being discharged to the outside of the system and can be efficiently reduced in the end.

JP 2001-104737 A (pages 1 to 3) Japanese Unexamined Patent Publication No. 2003-19435 (first page, second page)

  In view of the above-mentioned problems of the prior art, an object of the present invention is to use one of the causative substances of the global warming phenomenon by effectively using an inexpensive substance that does not require a special acquisition route or a substance that can be industrial waste. The carbon dioxide is efficiently adsorbed and separated, and further, the desorbed carbon dioxide can be recovered without inadvertently discharging out of the system, and finally the carbon dioxide emission can be efficiently reduced. The object is to provide a carbon dioxide adsorption system and a carbon dioxide desorption / recovery system.

  In order to achieve the above object, the present inventor has conducted extensive research on a system for adsorbing, separating and recovering carbon dioxide, and as a result, has found a specific adsorption device using an adsorbent mainly composed of a specific inorganic powder component. When used, carbon dioxide can be efficiently adsorbed, and furthermore, carbon dioxide can be efficiently recovered without inadvertently discharging the carbon dioxide desorbed from the adsorption device out of the system. The present invention has been completed by discovering that the amount of emission can be reduced.

  That is, according to the first invention of the present invention, a bauxite powder, a dry powder of a precipitate produced as a by-product in the Bayer method, or a porous powder having a supernatant pH of 7 or more when a suspension is prepared. The adsorbent mainly composed of at least one inorganic powder component is filled into an adsorption container having a gas supply port and a gas discharge port, and a carbon dioxide-containing gas is introduced into the gas supply port, and the adsorption is performed in the adsorption container. There is provided a carbon dioxide adsorption system characterized in that carbon dioxide is selectively adsorbed on an agent and gas having a reduced carbon dioxide concentration is discharged from a gas outlet.

  Further, according to the second invention of the present invention, a bauxite powder, a dry powder of a precipitate produced as a by-product in the Bayer method, or a porous powder having a supernatant pH of 7 or more when a suspension is prepared is selected. A filter formed by adsorbing an adsorbent mainly composed of at least one inorganic powder component into a sheet shape is inserted into an adsorption container having a gas supply port and a gas discharge port, and a carbon dioxide-containing gas is introduced into the supply port. There is provided a carbon dioxide adsorption system characterized in that carbon dioxide is selectively adsorbed on the adsorbent in a container and gas having a reduced carbon dioxide concentration is discharged from a gas outlet.

  According to the third invention of the present invention, in the first invention, a porous plate is provided at the bottom of the adsorption vessel, and a carbon dioxide-containing gas is introduced into the gas supply port through the porous plate. A featured carbon dioxide adsorption system is provided.

  According to a fourth invention of the present invention, in any one of the first to third inventions, the dry powder of precipitate produced as a by-product in the Bayer method is an oxide of a transition metal typified by iron or A carbon dioxide adsorption system is provided that is produced from red mud, which is a mixture comprising hydroxide, sodium aluminosilicate, sodalite, and ash ore.

  According to a fifth aspect of the present invention, in any one of the first to third aspects, the porous powder is α-Al (OH) 3 (gibbsite), γ-AlO (OH) (boehmite). , Α-FeO (OH) (goethite / goethite), α-Fe 2 O 3 (hematite / hematite) or 5Fe 2 O 3 .9H 2 O (ferrihydrite) A featured carbon dioxide adsorption system is provided.

According to a sixth invention of the present invention, in any one of the first to fifth inventions, the powder containing the inorganic powder component as a main component has a specific surface area of 100 to 500 m ² / g. A carbon dioxide adsorption system is provided.

  According to a seventh aspect of the present invention, in the second aspect, the filter is made of a porous ceramic plate obtained by sintering a powder mainly composed of aluminum oxide. A carbon adsorption system is provided.

  According to the eighth invention of the present invention, the carbon dioxide adsorption system according to any one of the first to seventh inventions incorporates a recovery device comprising a decompression pump and a large-capacity temporary adsorption container into the carbon dioxide desorption system.・ It is a recovery system, and the decompression pump is connected to the gas outlet of the carbon dioxide adsorption system where carbon dioxide is adsorbed, and the carbon dioxide desorbed from the carbon dioxide adsorption system is adsorbed and held in the large-capacity temporary adsorption vessel A carbon dioxide desorption / recovery system is provided.

  According to the carbon dioxide adsorption system of the present invention, in the first to seventh inventions, an adsorption container filled with a powder capable of efficiently adsorbing carbon dioxide which is a causative substance of the global warming phenomenon, or the powder is used. It consists of an adsorbing device fitted with a filter formed into a sheet, and the raw material used as the adsorbent is a new use of an inexpensive substance that does not require a special route or a substance that can become industrial waste It is intended for development and effective use, and since it does not require special production energy in the preparation of the adsorbent, its industrial value is extremely large.

  In the eighth invention, carbon dioxide is efficiently discharged in consideration of the balance of carbon dioxide as a whole from an energy point of view without inadvertently discharging the desorbed carbon dioxide outside the system. This is more advantageous because the amount can be reduced.

Hereinafter, the carbon dioxide adsorption system and the desorption / recovery system that contribute to the suppression of the global warming phenomenon of the present invention will be described in detail.
The carbon dioxide adsorption system of the present invention is at least one selected from bauxite powder, dry powder of precipitate produced as a by-product in the Bayer method, or porous powder having a supernatant pH of 7 or more when a suspension is prepared. An adsorbent mainly composed of an inorganic powder component is filled in an adsorption container having a gas supply port and a gas exhaust port, or a filter formed by forming the adsorbent into a sheet or a powder mainly composed of aluminum oxide. A filter made of a porous ceramic plate obtained by sintering is inserted into an adsorption container having a gas supply port and a gas discharge port, a carbon dioxide-containing gas is introduced into the supply port, and carbon dioxide is introduced into the adsorbent in the container. Is selectively adsorbed, and the gas having a reduced carbon dioxide concentration is discharged from the gas discharge port.

  The carbon dioxide adsorption system of the present invention will be described with reference to the drawings. FIG. 1 shows an example of an apparatus in which an adsorbent containing the inorganic powder component as a main component is filled into a cylindrical or rectangular adsorption container. Further, FIG. 2 adsorbs a filter formed of a sheet of an adsorbent containing the inorganic powder component as a main component or a porous ceramic plate obtained by sintering powder containing an aluminum oxide as a main component. An example of the adsorption | suction apparatus inserted in the container inside is represented.

In FIG. 1, a carbon dioxide-containing gas is introduced from a gas supply port 3 of a carbon dioxide adsorption device 1 into a cylindrical or rectangular adsorption container 2 containing an adsorbent 5, and the adsorbent filled in the adsorption container 2. The carbon dioxide is selectively adsorbed by the gas 5 and the gas having a reduced carbon dioxide concentration is discharged from the gas outlet 4.
Further, the apparatus shown in FIG. 1 can be rotated 90 degrees to use the adsorption container 2 in a vertical state. Here, as the adsorption container 2, a plate having innumerable holes such as a perforated plate that does not spill out is used as the bottom plate, and the carbon dioxide-containing gas is introduced from the gas supply port 3 through the bottom plate. The structure is preferable. In this case, depending on conditions, the adsorbent in the adsorption vessel 2 becomes a fluidized bed, and the contact efficiency with the introduced gas can be further improved as a solid-gas contact reactor.

  In FIG. 2, a gas containing carbon dioxide is introduced into the adsorption container 6 from the gas supply port 3 of the carbon dioxide adsorption device 1, passes through the filter 7 made of the adsorbent 5, and carbon dioxide is selected as the adsorbent 5. Gas having a reduced carbon dioxide concentration is exhausted from the gas outlet 4.

The carbon dioxide adsorption system of the present invention is attached to, for example, an air cleaner in an automobile exhaust gas system or a piping system such as a house ventilation system, and selectively adsorbs carbon dioxide in the carbon dioxide-containing gas. The amount of the adsorbent, the size of the adsorption container, and the selection of the two types of adsorption containers can be appropriately selected depending on the type of carbon dioxide-containing gas, the flow rate, and the passing amount (volume). Further, the container is removed from the piping system when the adsorbent adsorbs carbon dioxide and the amount of adsorption is saturated or just before it is saturated, and is connected to a recovery device described later, so that the carbon dioxide adsorbed by the adsorbent To collect. Note that, depending on the apparatus, carbon dioxide adsorbed by the adsorbent can be recovered simply by incorporating a recovery apparatus described later into the entire apparatus and switching the piping system.
Moreover, the adsorption conditions etc. which use the carbon dioxide adsorption system of this invention can be arbitrarily determined with the conditions of the carbon dioxide containing gas made into object.

  The carbon dioxide desorption / recovery system of the present invention is a carbon dioxide recovery device incorporated subsequent to the carbon dioxide adsorption system. The carbon dioxide recovery device used in the present invention is composed of a decompression pump and a large-capacity temporary adsorption vessel, and is connected to the gas discharge port of the carbon dioxide adsorption device on which carbon dioxide is adsorbed, and is desorbed from the carbon dioxide adsorption device. It is a device that adsorbs and holds the carbon dioxide that has been absorbed in a large-capacity temporary adsorption vessel.

  Here, the carbon dioxide recovery apparatus of the present invention will be described with reference to the drawings. FIG. 3 shows an apparatus for desorbing carbon dioxide from an adsorbing apparatus filled with an adsorbent adsorbing carbon dioxide under reduced pressure and re-adsorbing the adsorbent in a large-capacity temporary adsorption container.

In FIG. 3, the gas discharge port 4 of the carbon dioxide adsorption device is connected to the suction line 11 of the carbon dioxide recovery device 10 and is sucked by the decompression pump 12 and re-adsorbed to the adsorbent 14 in the large-capacity temporary adsorption container 13. . A gas containing almost no carbon dioxide is discharged from the air opening 15. At this time, the gas supply port of the carbon dioxide adsorption device is closed.
Moreover, the desorption conditions using the carbon dioxide recovery apparatus of the present invention are not particularly limited, and can be arbitrarily determined.

  The carbon dioxide adsorbing apparatus in which carbon dioxide is desorbed from the adsorbent can be used again after the carbon dioxide adsorption performance returns to the initial state, but the adsorbent can be regenerated as necessary.

In addition, the carbon dioxide re-adsorbed by the adsorbent in the large-capacity adsorption container is recovered by means of the same decompression method or the like, if necessary, and used for each application through other containers or other suction lines. Can be used.
As the adsorbent in the large-capacity adsorption vessel, the same adsorbent as that used in the carbon dioxide adsorption apparatus can be used. Moreover, the capacity | capacitance etc. can be arbitrarily determined according to the carbon dioxide adsorption apparatus etc. to be used.

  In the carbon dioxide adsorption system of the present invention, as an adsorbent, a bauxite powder, a dry powder of a precipitate produced as a by-product in the Bayer method, or a porous powder having a supernatant pH of 7 or more when a suspension is prepared. Use of a powder comprising at least one selected inorganic powder component as a main component, or a filter formed by forming the powder into a sheet or a porous ceramic plate obtained by sintering a powder containing aluminum oxide as a main component is important. As an adsorbent that has both adsorption and desorption performance specific to carbon dioxide at the same time, it can control the release of carbon dioxide into the atmosphere and control the adsorption and desorption performance in an energy-saving manner. can do. In addition, it is possible to develop new uses and effectively use substances that can become industrial waste.

  Furthermore, in the desorption / recovery system of the present invention, it is important to use a carbon dioxide recovery device that recovers carbon dioxide desorbed from the adsorption system. This makes it possible to efficiently reduce carbon dioxide emissions while considering the balance of carbon dioxide as a whole from an energy point of view, without inadvertently discharging the desorbed carbon dioxide outside the system. it can.

  By the way, considering the technical means to suppress the release of carbon dioxide into the atmosphere, the essential problem seems to be the diffusivity of carbon dioxide. In other words, once carbon dioxide and other gaseous substances are released into the atmosphere and diffused, they are diluted rapidly with time, so that it is not possible to easily recover the entire amount. For example, a good example of a similar problem is the pollution problem that has occurred in the air, oceans and rivers, and overlooked the total amount of harmful emissions by being alert to the superficial phenomenon that any substance continues to dilute in nature. It can be understood that this is the result of the result.

  In response to such a problem, the carbon dioxide adsorption system and desorption / recovery system of the present invention have various sources before the carbon dioxide-containing gas is released, diffused, diluted and virtually impossible to recover. Carbon dioxide is immediately adsorbed and separated in situ from the gas generated in the process. Thereafter, the carbon dioxide can be desorbed by depressurization or heating treatment, and stored so that it can be used as needed as a useful resource for manufacturing industrial products. This also allows the adsorbent used in the adsorption system to maintain its adsorption performance and desorption performance over a long period of time, contributing to the construction of a resource recycling society.

  The adsorbent production method includes at least one inorganic powder component selected from bauxite powder, precipitate powder by-produced in the Bayer method, or porous powder having a supernatant pH of 7 or more when suspended. If treatments such as washing, drying, and heating are performed as raw materials under appropriate conditions, a fine active powder having both adsorption performance and desorption performance can be obtained by an energy-saving production method. Furthermore, the filter shape | molded into the sheet form using the normal shaping | molding method of inorganic powder using this powder is obtained. For example, after adding a binder to the inorganic powder and kneading, a sheet is obtained with a roller molding machine.

As the bauxite powder, not only a distribution product that can be obtained as a raw material of the buyer method but also a pulverized powder that is naturally generated when mining and transporting bauxite ore, there is an advantage that a special acquisition route is not required. The bauxite is composed of not only Al ₂ O ₃ .nH ₂ O but also α-AlO (OH) (diaspore), γ-AlO (OH) (boehmite), and the like.

  As the dry powder of the precipitate produced as a by-product in the Bayer method, for example, red mud produced as a by-product from bauxite powder by an alkali leaching method using a sodium hydroxide solution in the Bayer method is used. This red mud is a mixture containing an oxide or hydroxide of a transition metal typified by iron, sodium aluminosilicate, sodalite, and ash ore. It is industrially beneficial to construct a new application for effective utilization by drying and grinding.

  Examples of the porous powder include α-Al (OH) 3 (gibbsite), γ-AlO (OH) (boehmite), α-FeO (OH) (goethite / goethite), α-Fe 2 O 3 ( There is a dry powder of natural minerals found in soil containing at least one selected from hematite / hematite) or 5Fe2O3.9H2O (ferrihydrite), which has the advantage of not requiring a special access route.

It does not specifically limit as a specific surface area of the powder which has the said inorganic powder component as a main component, 100-500 m < ² > / g is preferable. Further, the particle diameter of the powder is not particularly limited and is preferably 1 to 200 μm. That is, carbon dioxide can be efficiently adsorbed and desorbed within these ranges.

  Further, in the carbon dioxide adsorption system, a porous ceramic plate obtained by sintering a powder mainly composed of aluminum oxide instead of a filter formed by forming the adsorbent mainly composed of the inorganic powder component into a sheet shape It is preferable to use a filter made of the above-mentioned because the porous ceramic plate can serve both as an adsorbent and a filter.

The powder mainly composed of aluminum oxide used for the porous ceramic is not particularly limited, and α-alumina, n-alumina, θ-alumina, γ-alumina, η-alumina, χ-alumina, etc. In addition to aluminum oxide, there may be mentioned powder composed of at least one oxide selected from SiO ₂ (silicon dioxide), α-Fe ₂ O 3 (hematite / hematite), and alkali metal or alkaline earth metal. Examples of raw materials from which the powder can be obtained include unsuccessful moldings of alumina products, unsuccessful moldings of alumina abrasives such as corundum (steel balls), and polishing residues. These raw materials are preferable because they have the advantage of not requiring a special acquisition route and can effectively use substances that can become industrial waste.
The method for sintering the powder is not particularly limited, and is an ordinary method for producing a sintered body from the powder containing aluminum oxide as a main component, for example, the powder compact is subjected to high-temperature conditions or processing. A method of firing under pressure is used.

  The carbon dioxide recovered from the large-capacity temporary adsorption container of the present invention can be used to improve the efficiency of photosynthesis in crops in closed-system intensive agriculture such as a greenhouse, and can be used for extinguishing digesters and dry ice. It is used for effective use such as utilization as a raw material.

  The carbon dioxide adsorption device and the desorption / recovery device of the present invention are used as means for suppressing the emission of carbon dioxide generated in the housing industry, the automobile industry, the electric power industry, the gas industry, and the like. For example, specifically, in the automobile industry, the carbon dioxide concentration in the exhaust gas can be reduced by mounting the above-described adsorption device in an air cleaner in an automobile exhaust gas system, and in the housing industry, ventilation is performed for 24 hours. By incorporating the above-described adsorption device into the system, it is possible to provide a house that can reduce the discharge of carbon dioxide due to human activities (heating, cooking, breathing, etc.) to the outdoors.

Hereinafter, the present invention will be described in more detail by way of examples and comparative examples of the present invention, but the present invention is not limited to these examples. In addition, the analysis method of the chemical composition used in the Examples and Comparative Examples, the specific surface area, the representative particle diameter (mass basis), and the evaluation method of the CO ₂ adsorption amount are as follows.
(1) Analysis of chemical composition: It was performed by a fluorescent X-ray diffraction method.
(2) Measurement of specific surface area: The BET method was used.
(3) Measurement of representative particle diameter (mass basis): Measured by light scattering diffraction method or gravity sedimentation method.
(4) Measurement of CO ₂ adsorption amount: Improved method of microdiffusion analysis (Soil Science and Plant Nutrition (ISSN 0038-0768), Japan Society of Soil Fertilizer, Vol. 41, No. 1, 1995, p. 141-146).

Example 1
1 is charged with 1000 g of bauxite powder (Al ₂ O ₃ .nH ₂ O) having a specific surface area of 100 m ² / g as an adsorbent, and a carbon dioxide-containing gas (CO ₂ concentration 1 volume). %, N ₂ concentration 78 volume%, O ₂ concentration 20 volume%, and other gases (Ar, etc. 1 volume%) were supplied at 100 L / min. The temperature of the gas supplied to the adsorption vessel was adjusted to 40 ° C. After aeration for 10 min, the CO ₂ adsorption amount was determined. The results are shown in Table 1.

(Example 2)
The amount of CO ₂ adsorption was determined in the same manner as in Example 1 except that a dry powder of red mud having a specific surface area of 100 m ² / g was used as the adsorbent. The results are shown in Table 1.

(Example 3)
The amount of CO ₂ adsorption was determined in the same manner as in Example 1 except that a dry powder of red mud having a specific surface area of 200 m ² / g was used as the adsorbent. The results are shown in Table 1.

Example 4
The amount of CO ₂ adsorption was determined in the same manner as in Example 1 except that a dry powder of red mud having a specific surface area of 300 m ² / g was used as the adsorbent. The results are shown in Table 1.

(Example 5)
The amount of CO ₂ adsorption was determined in the same manner as in Example 1 except that a dry powder of red mud having a specific surface area of 500 m ² / g was used as the adsorbent. The results are shown in Table 1.

(Example 6)
The amount of CO ₂ adsorption was determined in the same manner as in Example 1 except that a dry powder of gibbsite (α-Al (OH) 3) having a specific surface area of 100 m ² / g was used as the adsorbent. The results are shown in Table 1.

(Example 7)
The adsorption device after adsorbing carbon dioxide in Example 1 was connected to a carbon dioxide recovery device of the system shown in FIG. Next, the gas supply port of the carbon dioxide adsorbing device was closed, and suction was performed under reduced pressure to collect carbon dioxide in a large capacity temporary adsorption container. The recovery rate was 98% of the adsorbed carbon dioxide.

(Comparative Example 1)
The amount of CO ₂ adsorption was determined in the same manner as in Example 1 except that synthetic zeolite (Al ₂ O ₃ : 46% by weight, SiO ₂ : 36%, Fe ₂ O ₃ : 18% by weight) was used as the adsorbent. . The results are shown in Table 1.

From Table 1, in Examples 1-6, bauxite powder as adsorbent, dry powder of precipitate produced as a by-product in the Bayer method, or porous powder having a supernatant pH of 7 or more when a suspension is prepared. Since the built-in carbon dioxide adsorption system was used, it can be seen that a high amount of CO ₂ adsorption can be obtained and carbon dioxide can be adsorbed efficiently. On the other hand, in Comparative Example 1, since the type of the adsorbent does not meet these conditions, it can be seen that the CO ₂ adsorption amount is low and satisfactory results cannot be obtained.
Moreover, in Example 7, it turns out that the adsorbed carbon dioxide is efficiently recovered.

  As is clear from the above, the carbon dioxide adsorption system of the present invention is a carbon dioxide reduction target that is required to reduce emissions as a main cause of the greenhouse effect in the housing industry, automobile industry, electric power industry, gas industry, etc. (For example, contribute to the achievement of the Kyoto Protocol). In addition, since it can be extended to various other uses, it is useful as a technology that contributes to the construction of a substantial resource recycling society. Moreover, as the adsorbent, an inexpensive substance that does not require a special acquisition route or a substance that can be industrial waste can be used.

It is a figure showing an example of the apparatus with which the adsorption agent was filled into the adsorption container of cylindrical shape or a rectangular parallelepiped shape. Obtained by sintering powders mainly composed of filter or aluminum oxide (α-alumina, n-alumina, θ-alumina, γ-alumina, η-alumina, χ-alumina, etc.) formed by adsorbent in sheet form It is a figure showing an example of the apparatus which inserted the filter which consists of a porous ceramic board manufactured in the adsorption | suction container. It is a figure showing an example of the carbon dioxide recovery system of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Carbon dioxide adsorption device 2 Adsorption container 3 Gas supply port 4 Gas discharge port 5 Adsorbent 6 Adsorption vessel 7 Filter 10 Carbon dioxide recovery device 11 Suction line 12 Decompression pump 13 Large capacity temporary adsorption vessel 14 Adsorbent 15 Air release port

Claims (8)

  The main component is at least one inorganic powder component selected from bauxite powder, dry powder of precipitate produced as a by-product in the Bayer method, or porous powder that has a supernatant pH of 7 or higher when a suspension is prepared. The adsorbent is filled in an adsorption container having a gas supply port and a gas discharge port, a carbon dioxide-containing gas is introduced into the gas supply port, and the carbon dioxide is selectively adsorbed by the adsorbent in the adsorption vessel, and the gas discharge is performed. A carbon dioxide adsorption system characterized in that gas having a reduced carbon dioxide concentration is discharged from an outlet.   The main component is at least one inorganic powder component selected from bauxite powder, dry powder of precipitate produced as a by-product in the Bayer method, or porous powder that has a supernatant pH of 7 or higher when a suspension is prepared. A filter formed by adsorbing the adsorbent into a sheet is inserted into an adsorption container having a gas supply port and a gas discharge port, a carbon dioxide-containing gas is introduced into the supply port, and carbon dioxide is selectively used as the adsorbent in the container. The carbon dioxide adsorption system is characterized in that the gas having a reduced carbon dioxide concentration is discharged from the gas discharge port.   The carbon dioxide adsorption system according to claim 1, wherein a carbon plate-containing gas is introduced into a gas supply port through a porous plate provided at the bottom of the adsorption container.   The dry powder of the precipitate formed as a by-product in the Bayer method is produced from red mud, which is a mixture containing an oxide or hydroxide of a transition metal typified by iron, sodium aluminosilicate, sodalite, and ash ore. The carbon dioxide adsorption system according to any one of claims 1 to 3, wherein:   The porous powder includes α-Al (OH) 3 (gibbsite), γ-AlO (OH) (boehmite), α-FeO (OH) (goethite / goethite), α-Fe 2 O 3 (hematite / hematite). Or it is a dry powder of the natural mineral containing at least 1 sort (s) chosen from 5Fe2O3 * 9H2O (ferrihydrite), The carbon dioxide adsorption system of any one of Claims 1-3 characterized by the above-mentioned. The inorganic powder of the powder component as the main component is carbon dioxide adsorption system according to any one of claims 1 to 5, specific surface area characterized by a 100 to 500 m 2 / ^g.   The carbon dioxide adsorption system according to claim 2, wherein the filter is made of a porous ceramic plate obtained by sintering powder mainly composed of aluminum oxide. A carbon dioxide desorption / recovery system in which a carbon dioxide adsorption system according to any one of claims 1 to 7 is incorporated with a recovery device composed of a vacuum pump and a large-capacity temporary adsorption vessel,
The carbon dioxide adsorption system to which carbon dioxide has been adsorbed is connected to the gas discharge port of the carbon dioxide adsorption system, and carbon dioxide desorbed from the carbon dioxide adsorption system is adsorbed and held in the large-capacity temporary adsorption vessel. Carbon desorption / recovery system.

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