Concentration system

Abstract

To provide a concentration system which is compact and can concentrate a specific gas with low energy compared to conventional concentration systems.SOLUTION: A concentration system includes: a gas introduction unit which introduces a mixed gas containing a first gas and a second gas; a physical adsorption concentration unit which generates a first concentration gas, formed by concentrating the first gas, from the mixed gas introduced into the gas introduction unit by physical adsorption and separates the first concentration gas and a first exhaust gas containing the second gas from each other; a membrane separation concentration unit which generates a second concentration gas, formed by concentrating the first gas, from the first concentration gas, generated by the physical adsorption concentration unit, by membrane separation and separates the second concentration gas and a second exhaust gas containing the second gas from each other; and a second gas concentration unit which generates a third concentration gas, formed by concentrating the second gas, from the first exhaust gas and / or the second exhaust gas and separates the third concentration gas and a third exhaust gas from each other. The second gas separation unit is configured to introduce the third exhaust gas into the physical adsorption concentration unit.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a concentration system. [Background technology]

[0002] In recent years, efforts have been made to achieve a carbon-neutral society by separating and capturing carbon dioxide from exhaust gases emitted by power generation facilities and the atmosphere (hereinafter simply referred to as exhaust gases, etc.), and then producing carbon compounds from the captured carbon dioxide or cultivating microorganisms using the carbon dioxide.

[0003] Methods for separating carbon dioxide from exhaust gases and the like include, for example, an amine absorption method in which an amine compound absorbs carbon dioxide through a chemical reaction (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-45570 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the amine absorption method has problems in that it requires large-scale equipment and requires a large amount of energy to recover carbon dioxide.

[0006] Therefore, an object of the present invention is to provide an enrichment system that is compact and can enrich a specific gas with less energy than conventional systems. [Means for solving the problem]

[0007] One aspect of the present invention for solving the above-mentioned problems is a concentration system comprising: a gas inlet section that introduces a mixed gas containing a first gas and a second gas; a physical adsorption concentration section that generates a first concentrated gas by concentrating the first gas from the mixed gas introduced into the gas inlet section by physical adsorption and separates the first concentrated gas from a first exhaust gas containing the second gas; a membrane separation concentration section that generates a second concentrated gas by concentrating the first gas from the first concentrated gas generated in the physical adsorption concentration section by membrane separation and separates the second concentrated gas from a second exhaust gas containing the second gas; and a second gas concentration section that generates a third concentrated gas by concentrating the second gas from the first exhaust gas and / or the second exhaust gas and separates the third concentrated gas from the third exhaust gas, and the second gas concentration section introduces the third exhaust gas into the physical adsorption concentration section.

[0008] According to this aspect, the first concentrated gas obtained by concentrating the first gas by physical adsorption in the physical adsorption concentration section is further concentrated by membrane separation in the membrane separation concentration section, so that the second concentrated gas containing a high concentration of the first gas can be obtained in a more compact manner and with less energy than conventional methods. According to this aspect, the third exhaust gas separated from the third concentrated gas obtained by concentrating the second gas in the second gas concentration section is returned to the physical adsorption concentration section, so that the residue of the first gas contained in the third exhaust gas can be concentrated again in the physical adsorption concentration section, thereby improving the recovery rate of the first gas.

[0009] One aspect of the present invention is a concentration system including: a gas inlet section that introduces a mixed gas containing a first gas and a second gas; a mixed gas concentration section that concentrates the first gas from the mixed gas introduced into the gas inlet section and produces an enriched mixed gas containing the second gas; a physical adsorption concentration section that produces a first enriched gas by concentrating the first gas from the enriched mixed gas produced in the mixed gas concentration section by physical adsorption and separates the first enriched gas from a first exhaust gas containing the second gas; a membrane separation concentration section that produces a second enriched gas by concentrating the first gas from the first enriched gas produced in the physical adsorption concentration section by membrane separation and separates the second enriched gas from a second exhaust gas containing the second gas; and a second gas concentration section that produces a third enriched gas by concentrating the second gas from the first exhaust gas and / or the second exhaust gas and separates the third enriched gas from the third exhaust gas, and the second gas concentration section introduces the third exhaust gas into the physical adsorption concentration section.

[0010] According to this aspect, the first concentrated gas in which the first gas is concentrated by physical adsorption in the physical adsorption concentration section is further concentrated by membrane separation in the membrane separation concentration section, so that a second concentrated gas containing a high concentration of the first gas can be obtained in a more compact manner and with less energy than conventional methods. According to this aspect, the third exhaust gas separated from the third concentrated gas obtained by concentrating the second gas in the second gas concentration section is returned to the physical adsorption concentration section, so that the residue of the first gas contained in the third exhaust gas can be concentrated again in the physical adsorption concentration section, thereby improving the recovery rate of the first gas. According to this aspect, the first gas is first concentrated in the mixed gas concentration section and then concentrated in the physical adsorption concentration section, so that the first gas can be concentrated by physical adsorption even from a mixed gas with a low concentration of the first gas.

[0011] A preferred aspect includes an impurity gas separation section that separates impurity gas from the first exhaust gas and / or the second exhaust gas, and an impurity gas recovery section that recovers the impurity gas, and the impurity gas separation section supplies the first exhaust gas and / or the second exhaust gas from which the impurity gas has been separated to the second gas concentration section.

[0012] According to this aspect, the first exhaust gas and / or the second exhaust gas from which the impurity gases have been removed is supplied to the second gas concentrating section, so that a third concentrated gas with few impurities can be generated. According to this aspect, impurity gases in the third exhaust gas discharged from the second gas concentration section are also removed by passing through the impurity gas separation section, so that the third exhaust gas with fewer impurities can be returned to the physical adsorption concentration section.

[0013] In a preferred aspect, the impurity gases include sulfur oxides and / or nitrogen oxides.

[0014] In a preferred aspect, the physical adsorption concentration unit concentrates the first gas so that the concentration of the first gas in the first concentrated gas falls within a range of 60% to 98%.

[0015] In a preferred aspect, the membrane separation concentration unit concentrates the first gas so that the concentration of the first gas in the second concentrated gas falls within a range of 90% to 99.9%.

[0016] In a preferred aspect, the mixed gas concentrating unit concentrates the first gas so that the concentration of the first gas in the concentrated mixed gas falls within a range of 10% to 40%.

[0017] According to this aspect, the first gas can be easily concentrated by physical adsorption in the physical adsorption concentration section.

[0018] In a preferred aspect, the first gas is carbon dioxide.

[0019] In a preferred aspect, the second gas is nitrogen.

[0020] The above aspects may be made dependent on each other, or some of the configurations may be quoted or substituted for each other, as long as they are included in the technical scope of the present invention. [Effects of the Invention]

[0021] According to the present invention, a specific first gas can be concentrated in a compact manner and with lower energy consumption than conventional methods. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a diagram showing a schematic diagram of a concentration system according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing a schematic diagram of a concentration system according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, embodiments of the present invention will be described in detail.

[0024] The concentration system 1 of the first embodiment of the present invention is a gas recovery system that concentrates and recovers carbon dioxide and nitrogen from a mixed gas containing carbon dioxide and nitrogen. The concentration system 1 of this embodiment is suitable for use in concentrating mixed gases with a relatively high concentration of carbon dioxide, such as exhaust gases from coal-fired power plants, etc. (for example, mixed gases with a carbon dioxide concentration of 10% to 15%). As shown in Figure 1, the concentration system 1 includes a gas introduction section 2, a physical adsorption concentration section 3, a membrane separation concentration section 4, a first gas recovery section 5, an impurity gas separation section 6, an impurity gas recovery section 7, a second gas concentration section 8, and a second gas recovery section 9.

[0025] (Gas inlet 2) The gas inlet section 2 is a section for introducing a mixed gas containing at least carbon dioxide and nitrogen from the outside, and is capable of supplying the mixed gas to the physical adsorption concentration section 3. In the gas inlet portion 2 of this embodiment, the concentration of carbon dioxide in the mixed gas introduced is 10% or more, and the mixed gas is introduced in a state where the carbon dioxide concentration is somewhat higher than that of the atmosphere or the like.

[0026] (Physical adsorption concentration section 3) The physical adsorption concentration unit 3 is a part that generates a first concentrated gas by concentrating carbon dioxide from the mixed gas using a physical adsorption method, and separates the first concentrated gas from the first exhaust gas containing nitrogen. The physical adsorption method is not particularly limited as long as it uses physical adsorption, and for example, pressure swing adsorption (hereinafter also simply referred to as PSA method) or thermal swing adsorption (hereinafter also simply referred to as TSA method) can be used. The physical adsorption concentration section 3 of this embodiment concentrates carbon dioxide so that the concentration of carbon dioxide in the first concentrated gas falls within the range of 60% to 98%, and nitrogen is contained among the gases other than carbon dioxide in the first concentrated gas. Furthermore, when used alone, the physical adsorption concentration unit 3 has a carbon dioxide recovery rate of 85% to 95%. In other words, in the concentration system 1, the first exhaust gas separated by the physical adsorption concentration unit 3 also contains a small amount of carbon dioxide. The physical adsorption concentration section 3 is capable of supplying the separated first concentrated gas to the membrane separation concentration section 4 and the first discharge gas to the impurity gas separation section 6.

[0027] (Membrane separation concentration section 4) The membrane separation concentration unit 4 is a section that generates a second concentrated gas by concentrating carbon dioxide from the first concentrated gas using membrane separation, and separates the second concentrated gas from the second exhaust gas containing nitrogen. The separation membrane used in the membrane separation concentration section 4 is not particularly limited as long as it can selectively permeate and concentrate carbon dioxide from the first concentrated gas, and for example, a polymer membrane such as polyimide can be used. The membrane separation concentration unit 4 of this embodiment concentrates carbon dioxide so that the concentration of carbon dioxide in the second concentrated gas falls within the range of 90% to 99.9%. Furthermore, when used alone, the membrane separation concentration unit 4 has a carbon dioxide recovery rate of 85% to 95%. In other words, in the concentration system 1, the second exhaust gas separated in the membrane separation concentration unit 4 also contains a small amount of carbon dioxide. The membrane separation concentration unit 4 is capable of supplying the separated second concentrated gas to the first gas recovery unit 5, and is capable of supplying the second discharge gas to the impurity gas separation unit 6.

[0028] (First gas recovery section 5) The first gas recovery section 5 is a section for recovering the second concentrated gas, which has been concentrated in the membrane separation concentration section 4 and has a carbon dioxide concentration of 90% or more.

[0029] (Impurity gas separation section 6) The impurity gas separation section 6 is a section that separates and removes impurity gases from the first exhaust gas discharged from the physical adsorption concentration section 3 and / or the second exhaust gas discharged from the membrane separation concentration section 4. The impurity gas separation section 6 is capable of supplying the impurity gas separated from the first exhaust gas and / or the second exhaust gas to the impurity gas recovery section 7, and supplying the first exhaust gas and / or the second exhaust gas from which the impurity gas has been removed to the second gas concentration section 8. The impurity gas separation section 6 of this embodiment separates and removes impurity gases from the first exhaust gas discharged from the physical adsorption concentration section 3 and the second exhaust gas discharged from the membrane separation concentration section 4. The impurity gas preferably contains sulfur oxides and / or nitrogen oxides.

[0030] (Impurity gas recovery section 7) The impurity gas recovery section 7 is a section that recovers the impurity gas separated from the first exhaust gas and / or the second exhaust gas.

[0031] (Second gas concentrator 8) The second gas concentrating section 8 is a section that generates a third concentrated gas by concentrating nitrogen from the first exhaust gas and the second exhaust gas, and separates the third concentrated gas from the third exhaust gas. The method for concentrating nitrogen in the second gas concentrating section 8 is not particularly limited, and for example, a physical adsorption method such as a PSA method or a TSA method can be used. The second gas concentrating section 8 of this embodiment concentrates nitrogen so that the nitrogen concentration in the third concentrated gas falls within the range of 60% to 99.9%, and preferably concentrates nitrogen so that the nitrogen concentration falls within the range of 90% to 99.9%. The second gas concentrating section 8 is capable of supplying the separated third concentrated gas to the second gas recovery section 9, and is capable of supplying the third discharge gas to the physical adsorption concentrating section 3.

[0032] (Second gas recovery section 9) The second gas recovery section 9 is a section for recovering the third concentrated gas concentrated in the second gas concentration section 8.

[0033] According to the concentration system 1 of this embodiment, carbon dioxide is concentrated by combining physical adsorption by the physical adsorption concentration section 3 and membrane separation by the membrane separation concentration section 4, so that the second concentrated gas containing a high concentration of carbon dioxide can be recovered in a compact and low-energy manner. According to the concentration system 1 of this embodiment, the first concentrated gas in which carbon dioxide has been concentrated by physical adsorption in the physical adsorption concentration unit 3 is further concentrated by membrane separation in the membrane separation concentration unit 4. In other words, membrane separation, which alone does not easily produce high-purity carbon dioxide, is performed on the first concentrated gas in which carbon dioxide has been concentrated by physical adsorption, so that a second concentrated gas containing a high concentration of carbon dioxide can be recovered. According to the concentration system 1 of this embodiment, the third exhaust gas separated from the third concentrated gas in the second gas concentration section 8 is returned to the physical adsorption concentration section 3, so that the residual carbon dioxide contained in the third exhaust gas can be concentrated again in the physical adsorption concentration section 3, thereby improving the carbon dioxide recovery rate compared to conventional methods.

[0034] Next, a concentration system 100 according to a second embodiment of the present invention will be described. Note that the same components as those in the concentration system 1 according to the first embodiment will be denoted by the same reference numerals and will not be described again. The same applies hereinafter.

[0035] The concentration system 100 of the second embodiment of the present invention is suitable for use in concentrating a mixed gas with a low concentration of carbon dioxide, such as the atmosphere (for example, a mixed gas with a carbon dioxide concentration of 7% or less).

[0036] As shown in Figure 2, the concentration system 100 includes a gas introduction section 2, a mixed gas concentration section 102, a physical adsorption concentration section 3, a membrane separation concentration section 4, a first gas recovery section 5, an impurity gas separation section 6, an impurity gas recovery section 7, a second gas concentration section 8, and a second gas recovery section 9.

[0037] (Mixed gas concentrator 102) The mixed gas concentrating section 102 is a section that produces a concentrated mixed gas by concentrating carbon dioxide from the mixed gas introduced by the gas introducing section 2. The method for concentrating carbon dioxide in the mixed gas concentrating section 102 is not particularly limited, and for example, chemical absorption, physical absorption, physical adsorption, membrane separation, etc. can be used. The mixed gas concentrating section 102 of this embodiment generates concentrated mixed gas by concentrating carbon dioxide from the mixed gas by membrane separation. The mixed gas concentrating section 102 preferably concentrates carbon dioxide so that the concentration of carbon dioxide in the concentrated mixed gas falls within the range of 10% to 40%. This makes it easier to concentrate carbon dioxide in the physical adsorption concentrating section 3. The mixed gas concentrator 102 is capable of supplying the concentrated mixed gas to the physical adsorption concentrator 3 .

[0038] According to the second embodiment of the concentration system 100, even when concentrating a mixed gas with a low carbon dioxide concentration, such as atmospheric air, the mixed gas concentration section 102 concentrates the carbon dioxide to a concentration that can be concentrated in the physical adsorption concentration section 3, and then supplies it to the physical adsorption concentration section 3, so that a second concentrated gas with a high concentration of carbon dioxide can be recovered.

[0039] In the above embodiment, the first gas is carbon dioxide and the second gas is nitrogen, but the present invention is not limited to this. The first gas and the second gas may be any gas.

[0040] In the above-described embodiment, the first exhaust gas and the second exhaust gas separated in the physical adsorption concentration section 3 and the membrane separation concentration section 4 are introduced into the second gas concentration section 8 after impurity gases are removed in the impurity gas separation section 6, but the present invention is not limited to this. The first exhaust gas and the second exhaust gas may be supplied directly from the physical adsorption concentration section 3 and the membrane separation concentration section 4 to the second gas concentration section 8, or only the exhaust gas discharged from one of the concentration sections of the physical adsorption concentration section 3 and the membrane separation concentration section 4 may be passed through the impurity gas separation section 6 and then supplied to the second gas concentration section 8.

[0041] In the above-described embodiments, each component can be freely substituted or added between the respective embodiments as long as it falls within the technical scope of the present invention. [Explanation of symbols]

[0042] 1,100 Concentration System 2 Gas inlet 3 Physical adsorption concentration section 4 Membrane separation concentration section 8 Second gas enrichment section 102 Mixed gas concentration section

Claims

1. a gas introduction section that introduces a mixed gas containing a first gas and a second gas; a physical adsorption concentration section that generates a first concentrated gas by concentrating the first gas from the mixed gas introduced into the gas inlet section by physical adsorption, and separates the first concentrated gas from a first exhaust gas containing the second gas; a membrane separation concentration unit that generates a second concentrated gas by concentrating the first gas from the first concentrated gas generated in the physical adsorption concentration unit by membrane separation, and separates the second concentrated gas from a second exhaust gas containing the second gas; a second gas concentration unit that generates a third concentrated gas by concentrating the second gas from the first exhaust gas and / or the second exhaust gas, and separates the third concentrated gas from the third exhaust gas; The second gas concentration unit introduces the third exhaust gas into the physical adsorption concentration unit.

2. a gas introduction section that introduces a mixed gas containing a first gas and a second gas; a mixed gas concentration unit that concentrates the first gas from the mixed gas introduced into the gas inlet unit and generates a concentrated mixed gas containing the second gas; a physical adsorption concentration unit that generates a first concentrated gas by concentrating the first gas from the concentrated mixed gas generated in the mixed gas concentration unit by physical adsorption, and separates the first concentrated gas from a first exhaust gas containing the second gas; a membrane separation concentration unit that generates a second concentrated gas by concentrating the first gas from the first concentrated gas generated in the physical adsorption concentration unit by membrane separation, and separates the second concentrated gas from a second exhaust gas containing the second gas; a second gas concentration unit that generates a third concentrated gas by concentrating the second gas from the first exhaust gas and / or the second exhaust gas, and separates the third concentrated gas from the third exhaust gas; The second gas concentration unit introduces the third exhaust gas into the physical adsorption concentration unit.

3. an impurity gas separation unit that separates impurity gas from the first exhaust gas and / or the second exhaust gas; an impurity gas recovery unit that recovers the impurity gas, The concentration system according to claim 1 or 2, wherein the impurity gas separation unit supplies the first exhaust gas and / or the second exhaust gas from which the impurity gas has been separated to the second gas concentration unit.

4. The concentrating system of claim 3 , wherein the impurity gases include sulfur oxides and / or nitrogen oxides.

5. The concentration system according to claim 1 or 2, wherein the physical adsorption concentration unit concentrates the first gas so that the concentration of the first gas in the first concentrated gas falls within a range of 60% to 98%.

6. The concentration system according to claim 5 , wherein the membrane separation concentration unit concentrates the first gas so that the concentration of the first gas in the second concentrated gas falls within a range of 90% to 99.9%.

7. The concentration system according to claim 2 , wherein the mixed gas concentration unit concentrates the first gas so that the concentration of the first gas in the concentrated mixed gas falls within a range of 10% to 40%.

8. The concentrating system of claim 1 or 2, wherein the first gas is carbon dioxide.

9. 3. The concentrating system of claim 1, wherein the second gas is nitrogen.

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