Method for separating and recovering gas using renewable energy and renewable energy-based gas separation and recovery system

Abstract

To provide a method to realize energy consumption related to gas separation recovery and the reduction of a carbon dioxide gas discharge amount by performing gas separation recovery using a chemical absorption liquid utilizing renewable energy and to provide a renewable energy-utilized type gas separation recovery system applied with this technology.SOLUTION: The heating, regeneration and preheating of a chemical absorption liquid and the cooling of a regenerated chemical absorption liquid and a separation recovery gas are performed by renewable energy heat such as geothermal steam, biomass combustion heat, solar heat and the like. Mixed gas supply by the intake compression and blowing of an air-fuel mixture containing the separation recovery gas and electric equipment such as the supplying and circulation pump of the chemical absorption liquid and the like are driven by renewable energy electric power such as geothermal power generation, biomass power generation, photovoltaic power generation and the like.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for efficiently separating and recovering a gas by using renewable energy heat such as geothermal steam, geothermal fluid such as a self-flowing spring, biogas combustion heat, solar heat, etc. when separating and recovering a gas using a chemical absorption liquid, such as when separating and recovering carbon dioxide gas from biogas or the atmosphere using an amine-based chemical absorption liquid, and a renewable energy utilization type gas separation and recovery system to which this method is applied.

Background Art

[0002] In order to suppress and reduce the emission of carbon dioxide, which is a major cause of global warming, technologies for separating and recovering carbon dioxide gas contained in combustion exhaust gas during the use of fossil fuels and injecting and fixing it into an underground storage tank, negative emission technologies for separating and recovering carbon dioxide gas contained in air or biogas and fixing it, and furthermore, effective utilization technologies for carbon dioxide gas that effectively utilize the separated and recovered carbon dioxide gas as a raw material for chemical products and construct a carbon circulation system are expected.

[0003] Among these, as a method for separating and recovering carbon dioxide gas, after absorbing carbon dioxide into a chemical absorption liquid composed of an amine-based aqueous solution having high reactivity with carbon dioxide gas, the absorption liquid is heated by boiler steam, exhaust gas, etc. generated by the heat of combustion gas generated by the combustion of fossil fuels, so that while desorbing carbon dioxide gas, the chemical absorption liquid is regenerated, and then carbon dioxide gas is absorbed again into the regenerated chemical absorption liquid for circulation. A carbon dioxide gas separation and recovery technology using a chemical absorption liquid is widely known. In this technology, in order to suppress the emission of carbon dioxide gas during the time lag period from the start of boiler operation to the operation of the carbon dioxide separation and recovery device, boiler steam is generated using an electric heater with the discharge power obtained from a renewable energy power generation facility and a secondary battery, and the chemical absorption liquid is heated and regenerated, and a boiler plant technology (Patent Document 1) for suppressing the emission of carbon dioxide gas during the boiler startup process is disclosed.

[0004] Furthermore, in the aforementioned carbon dioxide gas separation and recovery technology using amine-based aqueous solutions, approximately 80% of the energy required for gas separation and recovery is consumed by heating and evaporating the water contained in the chemical absorbent solution. Therefore, in order to regenerate the chemical absorbent solution after carbon dioxide gas absorption, energy consumption is reduced by depressurizing the processing solution and using a stripping gas such as air or nitrogen. In addition, a technology (Patent Document 2) has been disclosed to improve the carbon dioxide gas absorption performance and absorption amount of the chemical absorbent solution by preheating the chemical absorbent solution before regeneration by exchanging heat between the chemical absorbent solutions before and after regeneration via a heat exchanger, or by cooling the chemical absorbent solution after regeneration with cooling water via a cooler. [Prior art documents]

[0005] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2021-107751 [Patent Document 2] Japanese Patent Publication No. 2021-178269 [Overview of the project] [Problems that the invention aims to solve]

[0007] As described above, the prior art described in Patent Document 1 allows for the efficient recovery of carbon dioxide gas from combustion exhaust gas, including during the startup process, in boilers and the like that utilize fossil fuels, thereby reducing carbon dioxide emissions during the use of boilers and the like. Furthermore, the prior art described in Patent Document 2 allows for the reduction of energy consumption and improvement of carbon dioxide separation and recovery efficiency in the heating and regeneration of the chemical absorbent that has absorbed carbon dioxide gas, which is a major cause of energy consumption and carbon dioxide emissions in the carbon dioxide separation and recovery process using a chemical absorbent. However, these technologies have the following three problems.

[0008] First, in the conventional technology described in Patent Document 1, during normal operation other than the startup process, and in the conventional technology described in Patent Document 2, the heat of steam obtained from a boiler using fossil fuels or the heat of exhaust gas generated at a waste incineration facility are used for the heating and regeneration of the chemical absorbent. Considering that the waste burned at waste incineration facilities also contains hydrocarbon compounds of fossil fuel origin, neither method utilizes renewable energy heat for heating and regeneration. This results in the consumption of fossil fuels and emission of carbon dioxide in the carbon dioxide separation and recovery process, which leads to a problem of reduced net carbon dioxide separation and recovery.

[0009] Furthermore, in the prior art described in Patent Document 1, while it is possible to reduce the consumption of fossil fuels and emissions of carbon dioxide related to the separation and recovery of carbon dioxide gas during the startup process of a boiler using fossil fuels by using renewable energy power such as solar power and wind power, and heating and regenerating the absorbent liquid by discharging secondary batteries charged with this power, this is limited to the startup process. Moreover, heating an electric heater with power supplied by variable power sources such as solar and wind power and secondary batteries presents challenges in terms of stable operation and sustained maintenance during long-term normal operation due to the instability of generated power and the limited storage capacity of secondary batteries. In addition, there are problems with low energy conversion efficiency related to the heating and regeneration of the chemical absorbent liquid due to power loss related to the conversion efficiency of generated power, the charging and discharging efficiency of secondary batteries, and the heating efficiency of electric heaters due to discharged power.

[0010] Furthermore, while all conventional technologies utilize coolers and cooling water for cooling the chemical absorbent and for removing condensation of water vapor and other substances contained in the separated and recovered gas, the specific method for supplying the cooling energy to these is not disclosed. If electricity or heat derived from fossil fuels is used for this cooling energy supply, it will result in the consumption of fossil fuels and the emission of carbon dioxide, leading to increased fuel costs, a decrease in the net amount of carbon dioxide separated and recovered, and the inability to apply the technology in areas where grid power connection is difficult, as well as the inability to continue operation during power outages.

[0011] Similarly, in all of the prior art described in Patent Document 2, such as the pressure reducing pump and the circulation pump for chemical absorbent liquid, the power used to drive the electrical equipment such as pumps, gas compressors, and gas blowers that make up the system is not derived from renewable energy. When the power used to drive this equipment is derived from fossil fuels, the costs associated with electricity consumption increase, the net amount of carbon dioxide separated and recovered decreases, the technology cannot be applied in areas where it is difficult to connect to the power grid, and the system cannot continue to operate during power outages.

[0012] Furthermore, the gases to which conventional technologies are applied include not only boiler exhaust gases using fossil fuels, but also carbon dioxide-containing gases such as biogas and combustion exhaust gases. However, these technologies do not include the separation and recovery of carbon dioxide gas generated when using combustible gases such as biomethane obtained when carbon dioxide is separated and recovered from biogas. Therefore, these conventional technologies alone have the problem of not being applicable to negative emissions, such as separating and recovering carbon dioxide from the atmosphere or separating, recovering, and fixing all carbon dioxide originating from biogas.

[0013] This invention has been made in view of these problems, and its purpose is to provide a method for separating and recovering gas using renewable energy, which can be applied to locations where it is difficult to connect to the power grid, and can also be applied to negative emissions of carbon dioxide, while reducing energy consumption costs and carbon dioxide emissions using renewable energy, and a renewable energy-based gas separation and recovery system to which this technology is applied. [Means for solving the problem]

[0014] To solve the above problems, the invention described in claim 1 is: In a gas separation and recovery process using a chemical absorbent, the gas is separated and recovered while heating and regenerating the chemical absorbent by one or more heat exchange methods, such as exchanging heat between the chemical absorbent that has absorbed the gas to be separated and recovered and a geothermal fluid via a heat exchanger, exchanging heat between a heat transfer fluid heated by geothermal energy, biomass combustion heat, or solar heat via a heat exchanger, or exchanging heat between a heat transfer fluid heated via an electric heater driven by renewable energy power and a heat exchanger.

[0015] The invention described in claim 2 is, The gas separation and recovery method according to claim 1 is characterized in that the chemical absorbent solution in which the gas to be separated and recovered has been absorbed is subjected to heat exchange with the geothermal fluid or heat transfer fluid after heat exchange via a heat exchanger, thereby preheating and raising the temperature of the chemical absorbent solution before heating and regeneration using the heat from the geothermal fluid or heat transfer fluid after heat exchange.

[0016] The invention described in claim 3 is, The present invention is characterized by cooling either the chemical absorbent after heating and regeneration, or the separated and recovered gas containing the vapor of the chemical absorbent, or both, using chilled water obtained by an absorption or adsorption type refrigerator driven by either the geothermal fluid or heat transfer fluid after heat exchange as described in claim 1, or either or both of the geothermal fluid or heat transfer fluid after preheating and heat exchange as described in claim 2, as a heat source.

[0017] The invention described in claim 4 is, The invention is characterized by cooling either the chemical absorbent after heating and regeneration, or the separated and recovered gas containing the vapor of the chemical absorbent, or both, using electricity obtained from a flash-type or binary-type generator driven by either the geothermal fluid or heat transfer fluid after heat exchange as described in claim 1, or either or both of the geothermal fluid or heat transfer fluid after preheating and heat exchange as described in claim 2, or chilled water obtained via a turbo chiller driven by renewable energy electricity.

[0018] The invention described in claim 5 is, A gas intake compressor directly connected to a turbine driven by geothermal fluid, the heat of biomass combustion, steam heated by geothermal energy or solar heat, or a gas intake compressor driven by renewable energy power sucks in and compresses an air mixture containing the separated and recovered gas, and promotes the absorption of the separated gas into the chemical absorption liquid by finely atomizing and ejecting the compressed gas into a tank of the chemical absorption liquid.

[0019] The invention according to claim 6 A gas intake blower directly connected to a turbine driven by geothermal fluid, the heat of biomass combustion, steam heated by geothermal energy or solar heat, or a gas intake blower driven by renewable energy power blows in an air mixture containing the separated and recovered gas into a container where the chemical absorption liquid flows down, thereby promoting the absorption of the separated gas into the chemical absorption liquid.

[0020] The invention according to claim 7 A liquid delivery circulation pump for the chemical absorption liquid directly connected to a turbine driven by geothermal fluid, the heat of biomass combustion, steam heated by geothermal energy or solar heat, or a liquid delivery circulation pump for the chemical absorption liquid driven by renewable energy power circulates either or both of the chemical absorption liquid that has absorbed the gas to be separated and recovered and the chemical absorption liquid that has been heated and regenerated by renewable energy.

[0021] The invention according to claim 8 Power obtained by a flash - type or binary - type generator driven by either or both of the geothermal fluid or heat - medium fluid after heat exchange according to claim 1 and the geothermal fluid or heat - medium fluid after pre - heating heat exchange according to claim 2, or renewable energy power drives any one or more of the refrigerator according to claim 3 and its auxiliary equipment, the generator according to claim 4 and the auxiliary equipment of the turbo - refrigerator, the gas intake compressor according to claim 5, the gas intake blower according to claim 6, and the liquid delivery circulation pump according to claim 7 and its auxiliary equipment.

[0022] The invention according to claim 9 Using any one or more of the geothermal fluid or heat medium fluid after heat exchange according to claim 1 and claim 2, the geothermal fluid or heat medium fluid after driving the refrigerator according to claim 3, and the geothermal fluid or heat medium fluid after driving the generator according to claim 4 to heat the methane fermentation tank of biomass, and separating and recovering carbon dioxide in the biogas by any one or more of the methods according to claims 1 to 8 from the biogas obtained from the methane fermentation tank.

[0023] The invention according to claim 10 By methane-fermenting biomass by the method according to claim 9, separating and recovering carbon dioxide gas from the obtained biogas, separating and recovering biogas-derived carbon dioxide gas and biomethane, and operating a power generation system or a combustion system using the recovered biomethane as fuel, while using the obtained renewable energy power and renewable energy heat as the power and heat according to claims 1 to 9, separating and recovering carbon dioxide gas contained in the exhaust gas from the power generation system or the combustion system by the method according to claims 1 to 9.

[0024] The invention according to claim 11 By methane-fermenting biomass by the method according to claim 10, and separating and recovering carbon dioxide gas in the obtained biogas and carbon dioxide gas of biomethane origin generated when using biomethane in the biogas, separating and recovering carbon dioxide gas of biomass origin.

[0025] The invention according to claim 12 A renewable energy utilization type carbon dioxide gas separation and recovery system that separates and recovers carbon dioxide gas in the air from the air using renewable energy by any one or more of the methods according to claims 1 to 8.

Effect of the Invention

[0027] [Figure 1] This is a schematic diagram showing a first embodiment of the present invention, which is a system for separating and recovering biomethane and biomass-derived carbon dioxide gas using geothermal steam. [Figure 2] This is a schematic diagram showing a second embodiment of the present invention, which is a system for separating and recovering biomass-derived carbon dioxide gas during biomass methane fermentation power generation. [Figure 3] This is a schematic diagram showing a third embodiment of the present invention, a system for separating and recovering atmospheric carbon dioxide gas using geothermal steam. [Figure 4] This is a schematic diagram showing a fourth embodiment of the present invention, a system for separating and recovering carbon dioxide gas from the atmosphere using solar thermal energy collection and photovoltaic power generation. [Modes for carrying out the invention]

[0028] The best mode for carrying out the present invention will be described below with reference to the drawings. The scope of the present invention is as described in the claims and is not limited to this embodiment.

[0029] (First Embodiment)

[0030] First, a separation and recovery system for biomethane and biomass-derived carbon dioxide gas utilizing geothermal steam, according to the first embodiment of the present invention, will be described with reference to Figure 1.

[0031] As shown in Figure 1, this system uses the energy of geothermal steam 3 to separate and recover biomethane and carbon dioxide gas from biogas generated in a methane fermentation tank 2, which produces biogas by methane fermentation of biomass resources 1 such as food waste and non-edible parts of agricultural and marine products. The biogas consists of biomethane, carbon dioxide, and trace components such as hydrogen sulfide.

[0032] In this system, a gas intake compressor 5, directly connected to a steam turbine 4 driven by geothermal steam, draws in and compresses a mixture of biomethane and carbon dioxide that has passed through a biogas purification device 6 that removes trace components such as hydrogen sulfide from the biogas. This mixture is then released into a carbon dioxide gas absorption facility 8 containing a chemical absorption liquid 7 such as an amine aqueous solution that absorbs carbon dioxide gas, via a microbubble gas supply pipe 9 that supplies the gas as fine bubbles such as microbubbles and nanobubbles. As carbon dioxide gas in the biogas is absorbed and removed by the chemical absorption liquid within this container, it is possible to recover the biomethane gas from which carbon dioxide has been removed through a biomethane extraction pipe 10 located at the top of the carbon dioxide gas absorption facility.

[0033] In this system, the chemical absorbent liquid that has absorbed carbon dioxide gas is supplied via the absorbent liquid circulation supply pump 11 to a chemical absorbent liquid regeneration facility 12, which performs desorption and recovery of carbon dioxide by heating and regenerating the chemical absorbent liquid. Furthermore, geothermal steam, which has been used to drive the geothermal steam turbine 4, is supplied as a heat source for heating and regenerating the chemical absorbent liquid within the regeneration facility. As a result, the chemical absorbent liquid is heated in the heating and regeneration container 13, and carbon dioxide gas is desorbed and released. After being separated and recovered via the carbon dioxide gas collection pipe 14, the recovered gas is cooled and the water vapor and condensed / liquefied components of the chemical absorbent liquid contained in the recovered gas are condensed and recovered, and the gas is returned to the chemical absorbent liquid circulation system. The carbon dioxide gas is then separated and recovered.

[0034] Furthermore, in the aforementioned chemical absorbent regeneration facility 12, the chemical absorbent regenerated by decarbonizing carbon dioxide gas in the heated regeneration container 13 is collected in the regenerated chemical absorbent collection pipe 16 and then supplied to the carbon dioxide gas absorption facility 8 to absorb carbon dioxide gas again, thus forming a circulating flow path. With this configuration, biomethane and carbon dioxide gas can be continuously separated and recovered from biogas using the energy of geothermal steam.

[0035] Furthermore, this system utilizes geothermal steam energy in multiple stages to improve the overall energy efficiency of the system and increase the net amount of carbon dioxide recovered by improving the separation and recovery efficiency of carbon dioxide gas and increasing the amount recovered. Specifically, in the chemical absorbent liquid that absorbs and desorbs carbon dioxide gas, in order to promote the regeneration of carbon dioxide gas from the chemical absorbent liquid (rich liquid) after carbon dioxide absorption by heating and releasing the carbon dioxide gas, a preheating heat exchanger 17 for the rich liquid is supplied with drain hot water generated by heat exchange with geothermal steam within the carbon dioxide gas absorption equipment 8 to preheat the rich liquid, and a chemical absorbent liquid heat exchanger 18 is provided to exchange heat with the chemical absorbent liquid (lean liquid) that has been regenerated after carbon dioxide has been desorbed to promote the preheating of the rich liquid. On the other hand, since the absorption performance and absorption capacity of the lean liquid improve as the temperature decreases, a lean liquid cooling heat exchanger 19 is provided to cool the lean liquid supplied to the carbon dioxide gas absorption equipment 8.

[0036] Here, the cooling water for cooling the lean liquid is circulating cooling water obtained by an adsorption chiller 20 that is driven using the hot water that has passed through the heat exchanger 17 for preheating the rich liquid as a heat source, thereby utilizing geothermal heat, which is a renewable energy source, to cool the lean liquid.

[0037] Furthermore, the circulation pump 11 for the chemical absorbent liquid and the adsorption chiller 20 that make up this system, as well as the electrical equipment such as pumps and cooling towers that make up the system, are all configured to be powered by renewable energy. In other words, the electrical equipment that makes up the system is powered by renewable energy obtained from a binary power generation system 21 that generates electricity using the high-temperature geothermal steam discharged after steam-liquid separation from the geothermal steam supplied to the chemical absorbent liquid regeneration facility 12 as a power source.

[0038] This configuration allows the system to operate independently of the power grid even in areas where connecting to the power grid is difficult, and also enables it to continue operating even if a power outage occurs when it is connected to the grid.

[0039] Furthermore, the hot water discharged after driving the binary power generation system 21 is supplied via a pump to the methane fermentation tank 2 for heating and maintaining its temperature before being discharged. This configuration ensures that methane fermentation of biomass can be carried out stably even in cold regions or during winter.

[0040] With the system configuration possessing the above features, this system can stably separate and recover biomethane and biomass-derived carbon dioxide gas from biomass, even in areas where connection to the power grid is difficult, independently of the grid. Furthermore, the separated and recovered biomethane and carbon dioxide gas can be compressed and stored in cylinders or the like by driving a compressor with electricity obtained from the binary power generation system, etc., and consumed as biomethane or industrial carbon dioxide gas at the demand site, or the carbon dioxide gas can be transported to a storage site and injected and fixed, thereby achieving negative emissions by recovering and fixing biomass-derived carbon dioxide gas. (Second Embodiment)

[0041] Next, a biomass-derived carbon dioxide gas separation and recovery system for biomass methane fermentation power generation, according to a second embodiment of the present invention, will be described with reference to Figure 2.

[0042] As shown in Figure 2, the system of the second embodiment differs from the first embodiment in that it uses biogas generated from the methane fermentation tank 2 as fuel to generate electricity through a biogas power generation system 22, and uses the generated electricity to operate a carbon dioxide gas separation and recovery system. It also uses the heat from the high-temperature exhaust gas obtained from the power generation system to heat and regenerate the chemical absorbent solution that absorbs carbon dioxide gas via the exhaust gas heat exchanger 23, to supply a heat source medium to drive the adsorption chiller, and to heat the methane fermentation tank in a stepwise manner, thereby recovering heat from the heat medium in the heat medium circulation system.

[0043] Furthermore, the high-temperature exhaust gas of the biogas power generation system generates condensate D when the circulating heat medium is heated in the heat exchanger 23. This condensate is then drained, and the exhaust gas intake compressor 5, which compresses the exhaust gas containing carbon dioxide and supplies it to the carbon dioxide gas absorption equipment 8, is operated by the power generated by the biogas power generation system. Additionally, the system is configured to supply surplus power generated by the biogas power generation system to the power grid G. These features differ from the first embodiment, but other features are the same as those of the first embodiment.

[0044] With this configuration, even in locations where geothermal steam cannot be obtained, such as biomass methane fermentation plants or sewage treatment plants, it is possible to use the biogas obtained at the installation site to generate biogas power while separating and recovering biomass-derived carbon dioxide gas. (Third embodiment)

[0045] Next, a third embodiment of the present invention, a system for separating and recovering atmospheric carbon dioxide gas using geothermal steam, will be described with reference to Figure 3.

[0046] As shown in Figure 3, the system of the third embodiment differs from the first embodiment in that geothermal steam 3 is directly supplied to the chemical absorbent regeneration equipment 12 and used for heating and regenerating the chemical absorbent, and electricity obtained from a geothermal power generation system 24 that generates electricity using geothermal steam produced by steam-liquid separation within the equipment is used to operate a gas intake blower 25 that draws in and blows in air (outside air) containing carbon dioxide gas, and a turbo chiller 26 for cooling the regenerated chemical absorbent, and the drawn-in outside air is supplied via a dust removal and dehumidification filter 27, and the carbon dioxide gas absorption tower 28 is configured to absorb carbon dioxide gas from the air as the chemical absorbent flows down the surface of the packing material. However, other features are the same as those of the first embodiment.

[0047] With this configuration, even in locations where biomass collection and methane fermentation are difficult, such as geothermal areas or hot spring areas where it is difficult to connect to the power grid, it is possible to separate and recover atmospheric carbon dioxide gas by utilizing the geothermal energy obtained at the installation site. (Fourth Embodiment)

[0048] Next, a fourth embodiment of the present invention, a system for separating and recovering carbon dioxide gas from the atmosphere using solar thermal collection and photovoltaic power generation, will be described with reference to Figure 4.

[0049] As shown in Figure 4, the fourth embodiment differs from the third embodiment in that the renewable energy heat used for heating, regenerating, and cooling the chemical absorbent is supplied by the circulation of a high-temperature heat transfer fluid obtained by the solar thermal collector 29, and the electrical equipment that operates the system is powered by renewable energy electricity supplied from the energy storage system 31, which stores electricity generated by the photovoltaic power generation system 30. However, other features are the same as those of the third embodiment.

[0050] With this configuration, as in the first, second, and third embodiments, it is possible to separate and recover carbon dioxide gas from the atmosphere by utilizing solar energy available at the installation site, even in locations where geothermal resources or biomass resources are unavailable and where connecting to the power grid is difficult. [Industrial applicability]

[0051] It should be noted that the present invention is not limited to the embodiments described above. For example, the illustrated embodiments are not limited to the separation and recovery of carbon dioxide gas. By changing the components of the chemical absorbent, other gases such as nitrogen and oxygen from the air may also be separated and recovered for use as industrial raw material gases.

[0052] Furthermore, the separated and recovered biomethane can be used as fuel or industrial raw material gas, and the separated and recovered carbon dioxide gas can be used as industrial raw material gas, or it can be fixed using known fixation methods. This makes it possible not only to recover and fix carbon dioxide contained in exhaust gases when using fossil fuels, but also to recover and fix carbon dioxide from the atmosphere or biomass.

[0053] Thus, the embodiments described above are illustrative, and any configuration that has substantially the same technical idea as described in the claims of the present invention and produces similar effects is included within the technical scope of the present invention. [Explanation of Symbols]

[0054] 1. Biomass resources 2. Methane fermentation tank 3. Geothermal steam 4. Steam Turbine 5. Gas intake compressor 6. Biogas purification system 7. Chemical absorbent 8. Carbon dioxide gas absorption equipment 9. Microbubble gas supply pipe 10. Biomethane extraction tube 11. Absorbent liquid circulation supply pump 12. Chemical absorbent liquid regeneration equipment 13... Heating regeneration container 14. Carbon dioxide gas collection pipe 15. Recovery gas cooler 16. Collection tube for regenerated chemical absorbent. 17. Heat exchanger for preheating rich liquids. 18. Chemical absorption liquid heat exchanger 19. Heat exchanger for lean liquid cooling 20...Adsorption refrigerator 21. Binary power generation system 22. Biogas power generation system 23. Exhaust gas heat exchanger 24. Geothermal power generation system 25. Gas intake and blower 26. Turbo chiller 27. Dust removal and dehumidification filter 28. Carbon dioxide gas absorption tower 29...Solar heat collector 30. Solar power generation system 31. Energy storage system

Claims

1. In a gas separation and recovery process using a chemical absorbent, A chemical absorbent solution that absorbed the gas to be separated and recovered Either exchange heat with geothermal fluids via a heat exchanger, Heat is exchanged between a heat transfer fluid heated by geothermal energy, biomass combustion heat, or solar heat, and a heat exchanger. The gas is separated and recovered while the chemical absorbent is heated and regenerated using one or more heat exchange methods. A method for separating and recovering gas using renewable energy, characterized in that the chemical absorbent liquid that has absorbed the gas to be separated and recovered is preheated and heated up before heating and regeneration by exchanging heat between the geothermal fluid or heat transfer fluid, whose temperature has decreased due to heat exchange, and the chemical absorbent liquid that has absorbed the gas to be separated and recovered, via a heat exchanger.

2. A method for separating and recovering gas using renewable energy according to Claim 1, characterized in that chilled water obtained by an absorption or adsorption type refrigerator driven by either or both of the geothermal fluid or the heat transfer fluid after preheating and heat exchange is used to cool either or both of the chemical absorbent liquid after heating and regeneration, or the separated and recovered gas containing the vapor of the chemical absorbent liquid.

3. The method for separating and recovering gas using renewable energy according to Claim 1, characterized in that the chemical absorbent after heating and regeneration, or the separated and recovered gas containing the vapor of the chemical absorbent, or both, is cooled using electricity obtained from a binary-type generator driven using either the geothermal fluid or the heat transfer fluid, or both, as a heat source, or chilled water obtained via a turbo chiller driven by renewable energy electricity.

4. The method for separating and recovering gas using renewable energy according to Claim 1, characterized in that a mixture containing the separated and recovered gas is compressed by intake air using electricity obtained from a binary-type generator driven by either or both of the geothermal fluid or the heat transfer fluid after preheating and heat exchange, or by renewable energy electricity, and the compressed gas is injected into a tank of chemical absorbent liquid in the form of fine bubbles to promote the absorption of the separated gas into the chemical absorbent liquid.

5. A method for separating and recovering gas using renewable energy according to Claim 1, characterized in that a biomass methane fermentation tank is heated using either or both of the geothermal fluid or the heat transfer fluid after preheat exchange, and carbon dioxide is separated and recovered from the biogas obtained from the methane fermentation tank.

6. A method for separating and recovering gas using renewable energy, as described in claim 5, characterized in that carbon dioxide gas and biomethane originating from biogas are separated and recovered by separating and recovering carbon dioxide gas from biogas, and the recovered biomethane is used as fuel to operate a power generation system or combustion system, and the renewable energy electricity and renewable energy heat obtained are utilized while separating and recovering carbon dioxide gas contained in the exhaust gas from the power generation system or combustion system.

7. A renewable energy-based carbon dioxide gas separation and recovery system characterized by separating and recovering biomass-derived carbon dioxide gas by methane fermentation of biomass using the method described in claim 6, and separating and recovering the carbon dioxide gas in the resulting biogas from the biomethane-derived carbon dioxide gas generated when utilizing the biomethane in the biogas.

8. A renewable energy-based carbon dioxide gas separation and recovery system characterized by separating and recovering carbon dioxide gas from air using renewable energy by the method described in any one of claims 1 to 6.

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