Carbon capture comprehensive utilization and energy recovery method and device

Abstract

The invention provides a carbon capture comprehensive utilization and energy recovery method and device. The device comprises a gas oxidation treatment power generation system, a heat recovery system, a carbon capture system, a carbon dioxide refining system, a carbon dioxide gasification system, a carbon conversion system and a heat exchange system. Raw material gas with high-concentration carbon dioxide gas is treated through the carbon dioxide refining system, and the raw material gas is converted into high-concentration liquid carbon dioxide to be stored. Impurity gas in the raw material gas is combusted through a gas oxidation treatment power generation system, and energy is recovered to supply power to a generator. Combusted high-temperature gas enters the carbon capture system after heat recovery and heat exchange, and enters the carbon dioxide refining system again for storage after concentration; high-concentration liquid carbon dioxide enters the carbon conversion system through the gasification system and is further converted into chemicals and fuel. According to the invention, efficient comprehensive utilization of capture, refining and conversion of carbon dioxide gas is realized, energy is recovered, and the method has the advantages of reducing energy consumption, improving resource utilization rate and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon capture, recycling and energy recovery, and in particular to a carbon capture, comprehensive utilization and energy recovery method and device. Background Art

[0002] As global warming and environmental pollution become increasingly serious, greenhouse gas emissions, especially carbon dioxide (CO2) emissions, have become one of the focuses of global attention. Carbon emissions mainly come from the use of fossil fuels such as industrial production, transportation and power plants. High carbon emissions in these areas are exacerbating global warming and posing a serious threat to the ecological environment. In response to climate change, many countries have set carbon neutrality goals and strive to reduce carbon emissions.

[0003] Carbon capture, utilization and storage (CCUS) technology has therefore become one of the key technologies in emission reduction strategies, aiming to reduce the concentration of greenhouse gases in the atmosphere at the source by capturing and recycling CO2 and effectively recycling carbon resources.

[0004] Existing carbon capture and utilization technologies mainly include physical absorption, chemical absorption, adsorption and membrane separation technology. Physical absorption usually uses organic solvents to absorb CO2, but the operation process consumes a lot of energy and has limited efficiency. Chemical absorption, such as using amine solvents to absorb CO2, is a widely used technology at present, but its disadvantage is that the solvent is easily degraded and corrosive, and the absorption and regeneration process consumes a lot of energy. The adsorption method captures CO2 through solid adsorbents, which has good selectivity and low energy consumption, but the adsorbent is easily saturated and needs to be regenerated frequently. Membrane separation technology separates CO2 through the selectivity of the membrane, but the membrane material is expensive and easily contaminated. Although these traditional methods can capture carbon dioxide, they generally have disadvantages such as high energy consumption, complex equipment, and limited recovery rate, making it difficult to achieve large-scale economic carbon capture.

[0005] In response to the urgent need for global carbon emission reduction, existing carbon capture technology is in urgent need of innovation and improvement. The future technical direction needs not only to improve the efficiency of CO2 capture, but also to reduce energy consumption and operating costs, and achieve more efficient and economical carbon capture and reuse. At the same time, combining energy recovery technology and combining carbon capture with energy conversion can convert captured CO2 into valuable energy or chemicals, thereby promoting sustainable development.

[0006] Therefore, it is necessary to provide a technical solution that can not only efficiently capture CO2 but also achieve energy recovery and comprehensive utilization, so as to meet increasingly stringent carbon emission targets and realize the effective recycling of resources. Summary of the invention

[0007] In accordance with the technical problems raised above, a method and device for comprehensive utilization of carbon capture and energy recovery are provided. The present invention mainly utilizes a carbon dioxide refining system to process raw gas with a relatively high concentration of carbon dioxide gas, and converts it into high-concentration liquid carbon dioxide for storage. The impurity gas in the raw gas is burned through a gas oxidation treatment power generation system, and the recovered energy is used to power the generator. The high-temperature gas after combustion enters the carbon capture system after heat recovery and heat exchange, and enters the carbon dioxide refining system again for storage after concentration; the high-concentration liquid carbon dioxide enters the carbon conversion system through the gasification system, and is further converted into chemicals and fuels. Thereby, the efficient and comprehensive utilization of the capture, refining and conversion of carbon dioxide gas is realized, and energy is recovered at the same time, which has the advantages of reducing energy consumption and improving resource utilization.

[0008] The technical means adopted by the present invention are as follows:

[0009] A carbon capture comprehensive utilization and energy recovery device, comprising: a gas oxidation treatment power generation system, a heat recovery system, a carbon capture system, a carbon dioxide refining system, a carbon dioxide gasification system, a carbon conversion system and a heat exchange system.

[0010] The raw gas to be treated enters the device from the carbon dioxide refining system, and the raw gas is a relatively high concentration carbon dioxide gas;

[0011] The carbon dioxide refining system is used to generate high-concentration liquid carbon dioxide from relatively high-concentration carbon dioxide gas and store it;

[0012] The carbon dioxide refining system is connected to the gas oxidation treatment power generation system, and is used to treat the gas containing impurities discharged from the top of the distillation tower and the storage tank in the carbon dioxide refining system through combustion by the gas turbine of the gas oxidation treatment power generation system, and recover the energy of the high-temperature gas generated by oxidation combustion to power the electric generator and the motor;

[0013] The gas oxidation power generation system and the heat recovery system are connected to the carbon capture system, the gas after combustion treatment passes through the heat recovery system and the heat exchange system and then enters the carbon capture system, and the steam generated after the reaction is respectively input into the carbon capture system and the carbon dioxide refining system;

[0014] The carbon capture system is connected to the carbon dioxide refining system and is used to generate carbon dioxide gas with a higher concentration from the gas after combustion treatment, and input it into the carbon dioxide refining system together with the raw gas;

[0015] The carbon dioxide gasification system is connected to the carbon dioxide refining system and the carbon conversion system, and is used to convert the stored high-concentration liquid carbon dioxide into high-concentration carbon dioxide gas through a heat exchange system, and input it into the carbon conversion system to generate chemicals and fuels.

[0016] Furthermore, the carbon dioxide refining system includes a steam turbine compressor unit, a desulfurization tower, a purification tower, a precooler, a heat exchanger, a liquefier, a refrigeration system, a distillation tower and a storage tank connected in sequence. Through compression, desulfurization purification, cooling liquefaction and distillation processes, the higher concentration carbon dioxide gas is further purified and liquefied to obtain high-concentration liquid carbon dioxide and stored in a storage tank.

[0017] Furthermore, the gas oxidation treatment power generation system includes a gas turbine generator set, which includes a gas turbine, a compressor and an electric generator I. The compressor compresses the air and then undergoes an oxidation combustion reaction in the combustion chamber of the gas turbine together with the gas containing impurities discharged from the top of the distillation tower and storage tank in the carbon dioxide refining system. The high-temperature and high-pressure gas generated drives the electric generator I to generate electricity.

[0018] Furthermore, the device also includes a combustible gas replenishment system, which includes a compressor and a motor. The compressor pressurizes the combustible gas and causes an oxidation combustion reaction to occur in the combustion chamber of the gas turbine together with the air compressed by the compressor and the gas containing impurities discharged from the top of the distillation tower and the storage tank. The high-temperature and high-pressure gas generated drives the electric generator I to generate electricity, and the generated electrical energy is used to power the motor.

[0019] Furthermore, the impurity gases contained in the raw gas include but are not limited to hydrogen, hydrocarbons, nitrogen, and gases containing VOCs; the combustible gas is one or more hydrocarbons, carbon monoxide or hydrogen gases; the combustion value of the gas entering the gas turbine should meet the requirements for combustion in the combustion chamber of the gas turbine.

[0020] Furthermore, the heat recovery system is a waste heat boiler, and the high-temperature gas exhausted by the gas turbine generates steam through the waste heat boiler, and then enters the carbon capture system and the carbon dioxide refining system; the gas exhausted from the waste heat boiler enters the heat exchange system for heat exchange and then enters the carbon capture system.

[0021] Furthermore, the carbon capture system includes three processes of alkaline washing and desulfurization, absorption, and desorption to capture low-concentration carbon dioxide and concentrate it into higher-concentration carbon dioxide gas, wherein the alkaline washing and desulfurization process adopts a pretreatment tower, the absorption process adopts an absorption tower, and the desorption process adopts a desorption tower; the pretreatment tower, the absorption tower and the desorption tower are connected in sequence; wherein the heat of the desorption tower is provided by the steam generated by the heat recovery system, and the desorption tower is connected to a bottom reboiler, and the steam is heat exchanged through the bottom reboiler to heat the absorbent to achieve desorption regeneration, and the condensed water after heat exchange is transported back to the heat recovery system.

[0022] Furthermore, the carbon dioxide gasification system includes a pressure pump and a precooler. One side of the pressure pump is connected to the storage tank of the carbon dioxide refining system, and the other side is connected to the precooler. The precooler is connected to the heat exchange gasifier. The pressure pump is used to pressurize the stored liquid carbon dioxide to the required pressure, and to exchange heat with the gas discharged from the heat recovery system through the heat exchange gasifier, thereby reducing the temperature of the gas entering the carbon capture system and gasifying the liquid carbon dioxide into gas.

[0023] The present invention also discloses a carbon capture comprehensive utilization and energy recovery method, which is carried out using the above-mentioned carbon capture comprehensive utilization and energy recovery device and comprises the following steps:

[0024] S1. The raw gas is pressurized by a centrifugal compressor and then enters the desulfurization tower and purification tower. After desulfurization and purification, it passes through a precooler, a heat exchanger, and a liquefier in sequence and enters a distillation tower and a storage tank. Through compression, desulfurization and purification, cooling liquefaction and distillation processes, the high-concentration carbon dioxide gas is further purified and liquefied to obtain high-concentration liquid carbon dioxide and stored in a storage tank;

[0025] S2. The gas containing impurities discharged from the top of the distillation tower and the storage tank enters the gas turbine of the gas oxidation treatment power generation system after passing through the heat exchanger, and undergoes oxidation combustion reaction with the air compressed by the compressor in the combustion chamber of the gas turbine. The high-temperature and high-pressure gas generated drives the compressor to pressurize the air, and the excess mechanical energy generated by the gas turbine drives the electric generator I to generate electricity;

[0026] S3, the high temperature gas discharged from the gas turbine generates steam through the waste heat boiler and discharges the gas;

[0027] S31, the gas discharged from the waste heat boiler is cooled by heat exchange in the heat exchange gasifier and enters the carbon capture system. The gas passes through the pretreatment tower, absorption tower and desorption tower in sequence, that is, the low-concentration carbon dioxide is captured and concentrated into a higher-concentration carbon dioxide gas through the alkaline washing desulfurization, absorption and desorption process; the higher-concentration carbon dioxide gas enters the carbon dioxide refining system, and then repeats the steps of S1 to store the high-concentration liquid carbon dioxide in the storage tank;

[0028] S32. A portion of the steam generated by the waste heat boiler is provided to the desorption tower in the carbon capture system to heat the absorbent for desorption and regeneration, and the other portion is provided to the steam turbine compressor unit of the carbon dioxide refining system to generate mechanical energy to drive the centrifugal compressor to compress the carbon dioxide. The excess steam can be used to drive the electric generator II through the steam turbine to generate electricity and be provided to other electrical equipment in the system;

[0029] S4. When preparing chemicals and fuels, the liquid carbon dioxide in the storage tank is converted into carbon dioxide gas through a pressure pump, a precooler, and a heat exchanger gasifier. The carbon dioxide gas is further converted into chemicals and fuels through a carbon conversion system.

[0030] Furthermore, in step S2, when the combustion value of the gas entering the gas turbine does not meet the combustion requirements in the combustion chamber of the gas turbine, combustible gas is introduced for supplementation. The pressurized combustible gas undergoes an oxidation combustion reaction in the combustion chamber of the gas turbine together with the air compressed by the compressor and the gas containing impurities discharged from the top of the distillation tower and the storage tank. The generated high-temperature and high-pressure gas drives the electric generator I to generate electricity. The generated electric energy is used to power the motor, and the excess electric energy is provided to other electrical equipment in the system.

[0031] Compared with the prior art, the present invention has the following advantages:

[0032] 1. The carbon capture, comprehensive utilization and energy recovery device provided by the present invention can efficiently purify carbon dioxide. The raw gas with a high concentration of carbon dioxide gas can be converted into high-concentration liquid carbon dioxide and stored in a storage tank, which not only improves the efficiency of carbon capture, but also reduces secondary emissions during the gas treatment process.

[0033] 2. The carbon capture comprehensive utilization and energy recovery device provided by the present invention, during the carbon dioxide refining process, the gas containing impurities is burned by the gas turbine in the gas oxidation treatment power generation system, which not only removes impurities in the gas, but also recovers the high-temperature gas generated by the combustion. The gas turbine is applied to the clean energy power generation field and industrial waste gas treatment field treated by clean technology, making greater contributions to the sustainable development of mankind with its advantages of high efficiency and low pollution.

[0034] 3. In the carbon capture, comprehensive utilization and energy recovery device provided by the present invention, the high-temperature steam generated by combustion is recovered by the heat recovery system to drive the generator and the motor, thereby realizing effective energy recovery and significantly reducing the energy consumption of the device, so that it can generate electricity while capturing and treating carbon dioxide, thereby improving the overall energy efficiency and providing a guarantee for the economic feasibility of carbon capture.

[0035] 4. The carbon capture, comprehensive utilization and energy recovery device provided by the present invention, the gas generated by combustion is further processed by a heat recovery system and a heat exchange system, ensuring that the carbon dioxide in the exhaust gas will not be discharged directly, but will be converted into a high-concentration gas through the carbon capture system and recycled, thereby maximizing the utilization of carbon resources, reducing pollution emissions to the atmosphere, and creating conditions for the subsequent refining and conversion of carbon dioxide.

[0036] 5. The carbon capture, comprehensive utilization and energy recovery device provided by the present invention gasifies high-concentration liquid carbon dioxide and converts it into valuable chemicals and fuels, such as methanol, ethylene, synthesis gas and other high-value products through a carbon conversion system. The carbon dioxide originally treated as waste gas is converted into a usable resource, promoting the carbon circular economy model.

[0037] In summary, compared with the traditional single carbon capture device, the technical solution of the present invention has the advantages of ensuring the high efficiency and sustainability of capture and refining through the synergistic effect of multiple systems, focusing on resource recovery and having higher economic and environmental benefits. Through carbon conversion, the direct emission of carbon dioxide is reduced, further mitigating the impact of greenhouse gases on the climate.

[0038] Based on the above reasons, the present invention can be widely promoted in the fields of efficient utilization of clean energy processed by clean technology, power generation, carbon capture and recycling, energy conservation, environmental protection, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0040] Figure 1 This is a schematic structural diagram of the carbon capture, comprehensive utilization and energy recovery device provided by the present invention.

[0041] Figure 2 This is a schematic structural diagram of the gas oxidation power generation system and heat recovery system in the carbon capture comprehensive utilization and energy recovery device provided by the present invention.

[0042] Figure 3 This is a schematic structural diagram of the carbon capture system portion of the carbon capture comprehensive utilization and energy recovery device provided by the present invention.

[0043] Figure 4 This is a schematic structural diagram of the carbon dioxide refining system portion of the carbon capture comprehensive utilization and energy recovery device provided by the present invention.

[0044] Figure 5 This is a schematic structural diagram of the carbon conversion system portion of the carbon capture, comprehensive utilization and energy recovery device provided by the present invention.

[0045] In the figure: 1. Combustible gas; 2. Air; 3. Compressor; 4. Motor; 5. Gas turbine; 6. Compressor; 7. Electric generator I; 8. Waste heat boiler; 9. Boiler feed water; 10. Steam; 11. Heat exchange gasifier; 12. Pretreatment tower; 13. Absorption tower; 14. Vent air I; 15. Desorption tower; 16. Bottom reboiler; 17. Gaseous carbon dioxide; 18. Raw gas; 19. Steam turbine; 20. Centrifugal compressor; 21. Electric generator II; 22. Desulfurization tower; 23. Purification tower; 24. Vent air II; 25. Heater; 26. Nitrogen; 27. Precooler; 28. Heat exchanger I; 29. ​​Liquefier; 30. Refrigeration system; 31. Distillation tower; 32. Storage tank; 33. Booster pump; 34. Hydrogen; 35. Gaseous carbon dioxide product; 36. Carbon conversion system; 37. Chemicals and fuels; 38. Gas-liquid separation tank I; 39. Heat exchanger II; 40. Gas-liquid separation tank II. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] Example 1

[0048] like Figure 1 As shown, the present invention provides a carbon capture comprehensive utilization and energy recovery device, including: a gas oxidation treatment power generation system, a heat recovery system, a carbon capture system, a carbon dioxide refining system, a carbon dioxide gasification system, a carbon conversion system and a heat exchange system. The various devices in the system are connected by pipelines, lines, etc.

[0049] The raw gas 18 mainly used for processing in the present invention is a relatively high concentration carbon dioxide gas, that is, a carbon dioxide gas with a concentration of more than 80%. On the one hand, the relatively high concentration carbon dioxide gas is converted into high-concentration liquid carbon dioxide through the carbon dioxide refining system and stored; on the other hand, the impurity gas remaining in the raw gas 18 after storage returns to the gas oxidation treatment power generation system and is mixed with the combustible gas 1 to enter the gas turbine 5 for combustion treatment to generate carbon dioxide gas, which enters the carbon capture system for capture and concentration and then enters the carbon dioxide refining system for treatment again.

[0050] like Figure 3 , Figure 4As shown, the raw gas 18 enters the device from the carbon dioxide refining system, and the carbon dioxide refining system is used to convert high-concentration carbon dioxide gas into high-concentration liquid carbon dioxide and store it. The carbon dioxide refining system includes a steam turbine compressor unit (composed of a steam turbine 19, a centrifugal compressor 20 and an electric generator II 21), a desulfurization tower 22, a purification tower 23, a precooler 27, a heat exchanger I 28, a liquefier 29, a refrigeration system 30, a distillation tower 31 and a storage tank 32 connected in sequence. Through compression, desulfurization purification, cooling liquefaction and distillation processes, the high-concentration carbon dioxide gas is further purified and liquefied to obtain high-concentration liquid carbon dioxide (liquid carbon dioxide with a concentration of more than 99%) and stored in the storage tank 32.

[0051] Specifically, the raw gas 18 enters the centrifugal compressor 20. The raw gas 18 has a low-pressure part and a non-pressurized part. After being compressed to above 2MPa by the centrifugal compressor 20, it enters the desulfurization tower 22 for desulfurization, and then enters the purification tower 23 for purification. Preferably, the purification tower 23 can adopt a double-group structure and a group working mode. A heater 25 for nitrogen backwash regeneration is also provided on one side of the purification tower 23. The nitrogen 26 enters the purification tower 23 for regeneration after being heated by the heater 25. A valve can be used to select to close one group of purification towers for regeneration and open another group for purification, and so on to ensure the normal operation of the device. The purified vent air II24 is discharged from the purification tower, and the vent air II24 is mainly nitrogen.

[0052] After purification, the raw gas 18 is recovered through the pre-cooler 27 and the heat exchanger I 28 for cold recovery, and then liquefied by the liquefier 29 to obtain high-concentration liquid carbon dioxide and enter the distillation tower 31, wherein the liquefier 29 provides cold energy for it through the refrigeration system 30 to liquefy the gas, and the liquid carbon dioxide enters the storage tank 32 from the bottom of the distillation tower 31 for storage.

[0053] The impurity-containing gas discharged from the top of the distillation tower 31 in the carbon dioxide refining system and the carbon dioxide gas discharged from the top of the storage tank 32 enter the gas turbine 5 of the gas oxidation treatment power generation system through the heat exchanger I28 for combustion treatment, and the energy of the high-temperature gas generated by the oxidation combustion is recovered to power the electric generator and the motor.

[0054] like Figure 2 As shown, specifically, the gas oxidation treatment power generation system includes a gas turbine generator set, and the gas turbine generator set includes a gas turbine 5, a compressor 6 and an electric generator Ⅰ7. The compressor 6 compresses the air 2 and then undergoes an oxidation combustion reaction in the combustion chamber of the gas turbine 5 together with the gas containing impurities discharged from the top of the distillation tower 31 and the storage tank 32 in the carbon dioxide refining system. The generated high-temperature and high-pressure gas drives the electric generator Ⅰ7 to generate electricity.

[0055] Preferably, when the combustion value of the gas entering the gas turbine 5 does not meet the requirements for combustion in the combustion chamber of the gas turbine 5, the device further comprises a combustible gas supplement system, the combustible gas supplement system comprises a compressor 3 and a motor 4, the compressor 3 pressurizes the combustible gas 1, and the combustible gas 1 and the air 2 compressed by the compressor 6 and the gas containing impurities discharged from the top of the distillation tower 31 and the storage tank 32 undergo an oxidation combustion reaction in the combustion chamber of the gas turbine 5, the high-temperature and high-pressure gas generated drives the electric generator I7 to generate electricity, and the generated electric energy is used to power the motor 4. It can be understood that the energy of the gas turbine 5 can be supplied to the electric generator I7 for power generation, can also be used to power the motor 4, and can also be used for the electric generator II 21 in the carbon dioxide refining system, and similarly, the energy of the centrifugal compressor 20 can also be supplied to the electric generator II 21 for power generation, and if there is a surplus, the excess electric energy can be provided to other electrical equipment in the system, as shown in the dotted line part in the figure.

[0056] Furthermore, the impurity gases contained in the raw gas 18 include but are not limited to hydrogen, hydrocarbons, nitrogen, and gases containing VOCs; the combustible gas 1 is one or more hydrocarbons, carbon monoxide or hydrogen gases; the addition of the combustible gas 1 and the addition of air 2 are both for the purpose of mixing with the gas discharged from the top of the distillation tower 31 and the storage tank 32 so that the combustion value after mixing meets the combustion requirements of the combustion chamber of the gas turbine 5.

[0057] In this embodiment, the gas oxidation treatment power generation system and the heat recovery system are connected to the carbon capture system. The heat recovery system includes a waste heat boiler 8 and a boiler feed water 9. The gas turbine 5 is connected to the waste heat boiler 8. The heat generated by the gas turbine 5 generates steam 10 through the waste heat boiler 8. The steam 10 is provided to the desorption tower 15 in the carbon capture system on the one hand to heat the absorbent for desorption and regeneration, and is provided to the steam turbine 19 of the carbon dioxide refining system to drive the centrifugal compressor 20 on the other hand. The gas coming out of the waste heat boiler 8 enters the carbon capture system after heat exchange and cooling in the heat exchange gasifier 11.

[0058] The carbon capture system includes three processes of alkaline washing desulfurization, absorption and desorption to capture low-concentration carbon dioxide and concentrate it into high-concentration carbon dioxide gas. The alkaline washing desulfurization process uses a pretreatment tower 12, the absorption process uses an absorption tower 13, and the desorption process uses a desorption tower 15.

[0059] Specifically, the pretreatment tower 12, the absorption tower 13 and the desorption tower 15 are connected in sequence; the top of the absorption tower 13 is connected to the gas-liquid separation tank I 38, and the gas discharged from the top of the absorption tower 13 is directly discharged as the vent gas I 14 through the gas-liquid separation tank I 38; the absorption liquid containing carbon dioxide coming out of the bottom of the absorption tower 13 enters the desorption tower 15 for desorption through the heat exchanger II 39, and the desorbed gaseous carbon dioxide 17 passes through the gas-liquid separation tank II 40 and merges with the raw gas 18, and then enters the centrifugal compressor 20 together for pressurization treatment. Among them, the heat of the desorption tower 15 is provided by the steam 10 generated by the waste heat boiler 8, and the desorption tower 15 is connected to the tower bottom reboiler 16. The steam 10 exchanges heat through the tower bottom reboiler 16 to heat the absorbent to achieve desorption regeneration, and the condensed water after heat exchange is transported back to the heat recovery system, which makes full use of the heat of the whole system, saves external energy consumption, and achieves low-cost operation.

[0060] The carbon capture system is connected to the carbon dioxide refining system and is used to convert the combustion treated gas into a carbon dioxide gas with a higher concentration, which is input into the carbon dioxide refining system together with the raw gas 18 to enter the purification and liquefaction process.

[0061] The application of the stored high-concentration liquid carbon dioxide is mainly reflected in: the carbon dioxide gasification system is connected to the carbon dioxide refining system and the carbon conversion system 36, which is used to convert the stored high-concentration liquid carbon dioxide into high-concentration carbon dioxide gas through a heat exchange system, and input it into the carbon conversion system to generate chemicals and fuels 37.

[0062] Specifically, the carbon dioxide gasification system includes a pressure pump 33 and a precooler 27. One side of the pressure pump 33 is connected to the storage tank 32 of the carbon dioxide refining system, and the other side is connected to the precooler 27. The precooler 27 is connected to the heat exchange gasifier 11. The pressure pump 33 is used to pressurize the stored liquid carbon dioxide to the required pressure, and to exchange heat with the gas discharged from the heat recovery system through the heat exchange gasifier 11, thereby reducing the temperature of the gas entering the carbon capture system and gasifying the liquid carbon dioxide into gas.

[0063] like Figure 5 As shown, the carbon conversion system 36 is used to convert high-purity carbon dioxide gas and hydrogen 34 and other hydrogen-containing substances into high-value-added chemicals and fuels 37 through thermal catalysis, electrocatalysis, photocatalysis and other conversion pathways and methods. In this embodiment, the gaseous carbon dioxide product 35 and hydrogen 34 after heat exchange in the heat exchange gasifier 11 are used to generate chemicals such as methanol.

[0064] Example 2

[0065] The present invention also provides a carbon capture comprehensive utilization and energy recovery method, which is carried out using the above-mentioned carbon capture comprehensive utilization and energy recovery device and comprises the following steps:

[0066] S1, the raw gas 18 is pressurized by the centrifugal compressor 20 and enters the desulfurization tower 22 and the purification tower 23. After desulfurization and purification, it passes through the precooler 27, the heat exchanger I 28, and the liquefier 29 in sequence and enters the distillation tower 31 and the storage tank 32. Through the compression, desulfurization and purification, cooling liquefaction and distillation process, the high-concentration carbon dioxide gas is further purified and liquefied to obtain high-concentration liquid carbon dioxide and stored in the storage tank 31;

[0067] The impurity-containing gas discharged from the top of S2, the distillation tower 31 and the storage tank 32 enters the gas turbine 5 of the gas oxidation treatment power generation system after passing through the heat exchanger I 28, and undergoes oxidation combustion reaction with the air 2 compressed by the compressor 6 in the combustion chamber of the gas turbine 5. The high-temperature and high-pressure gas generated drives the compressor 6 to compress the air, and the excess mechanical energy generated by the gas turbine 5 drives the electric generator I 7 to generate electricity;

[0068] Preferably, if the combustion value of the gas entering the gas turbine 5 does not meet the combustion requirements in the combustion chamber of the gas turbine 5, a combustible gas 1 is introduced for supplementation. The combustible gas 1 is pressurized and undergoes an oxidation combustion reaction in the combustion chamber of the gas turbine 5 together with the air 2 compressed by the compressor 6 and the gas containing impurities discharged from the top of the distillation tower 31 and the storage tank 32. The high-temperature and high-pressure gas generated drives the electric generator Ⅰ7 to generate electricity. The generated electric energy is used to power the motor 4, and the excess electric energy is provided to other electrical equipment in the system.

[0069] S3, the high temperature gas discharged from the gas turbine 5 is passed through the waste heat boiler 8 to generate steam 10 and discharge the gas;

[0070] S31, the gas discharged from the waste heat boiler 8 is cooled by heat exchange in the heat exchange gasifier 11 and enters the carbon capture system. The gas passes through the pretreatment tower 12, the absorption tower 13 and the desorption tower 15 in sequence, that is, the low-concentration carbon dioxide is captured and concentrated into a higher-concentration carbon dioxide gas through the alkaline washing desulfurization, absorption and desorption process; the higher-concentration carbon dioxide gas enters the carbon dioxide refining system, and then repeats the step of S1 to store the high-concentration liquid carbon dioxide in the storage tank 32;

[0071] S32, a part of the steam 10 generated by the waste heat boiler 8 is provided to the desorption tower 15 in the carbon capture system to heat the absorbent for desorption and regeneration, and the other part is provided to the steam turbine compressor unit of the carbon dioxide refining system to generate mechanical energy to drive the centrifugal compressor 20 to compress the carbon dioxide. The excess steam can drive the electric generator II 21 through the steam turbine to generate electricity and provide it to other electrical equipment in the system;

[0072] S4. When preparing chemicals and fuels, the liquid carbon dioxide in the storage tank 32 is converted into carbon dioxide gas through heat exchange by the pressure pump 33, the precooler 27, and the heat exchange gasifier 11. The carbon dioxide gas is further converted into chemicals and fuels 37 through the carbon conversion system.

[0073] Example 3

[0074] Specifically, the device of the present invention is used to treat a stream of raw gas 18 (4500 Nm 3 / h), first through the carbon dioxide refining system, the high-concentration liquid carbon dioxide at the bottom of the distillation tower 31 enters the storage tank 32 for storage, and the combustible gas components separated from the top of the distillation tower 31 recover energy and return to the gas oxidation treatment power generation system before mixing with 7100Nm 3 / h natural gas is combined and can generate about 24MW of electricity through the gas turbine 5, and the high-temperature exhaust gas can generate about 9MW of electricity through the waste heat boiler 8. The exhaust gas carbon dioxide is concentrated through the carbon capture system and then combined with the raw gas 18 to enter the carbon dioxide refining system, recovering about 150,000 tons of liquid carbon dioxide each year, and further through the carbon conversion system 36, about 100,000 tons of methanol can be produced.

[0075] The following table is a table of parameters of the raw material gas in this embodiment.

[0076] Serial number Components Normal content Remark 1 <![CDATA[CO2,10 -2 (v / v)]]> 94.5 2 <![CDATA[H2O,10 -2 (v / v)]]> saturation 3 <![CDATA[N2,10 -2 (v / v)]]> 1.0 4 <![CDATA[O2,10 -2 (v / v)]]> 0.2 5 <![CDATA[CO,10 -2 (v / v)]]> 0.9 6 <![CDATA[H2,10 -2 (v / v)]]> 0.4 7 <![CDATA[CH4,10 -2 (v / v)]]> 2.5 8 <![CDATA[C2H6,10 -2 (v / v)]]> 0.5 9 <![CDATA[Gas flow Nm 3 / h]]> 4500 10 Gas pressure MPa(G) 0.05 11 Gas temperature℃ ≤40

[0077] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, a person of ordinary skill in the art should understand that any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A carbon capture, comprehensive utilization and energy recovery device, comprising: Gas oxidation power generation system, heat recovery system, carbon capture system, carbon dioxide refining system, carbon dioxide gasification system, carbon conversion system and heat exchange system, characterized by: The raw gas to be treated enters the device from the carbon dioxide refining system, and the raw gas is a relatively high concentration carbon dioxide gas; The carbon dioxide refining system is used to generate high-concentration liquid carbon dioxide from relatively high-concentration carbon dioxide gas and store it; The carbon dioxide refining system is connected to the gas oxidation treatment power generation system, and is used to treat the gas containing impurities discharged from the top of the distillation tower and the storage tank in the carbon dioxide refining system through combustion by the gas turbine of the gas oxidation treatment power generation system, and recover the energy of the high-temperature gas generated by oxidation combustion to power the electric generator and the motor; The gas oxidation power generation system and the heat recovery system are connected to the carbon capture system, the gas after combustion treatment passes through the heat recovery system and the heat exchange system and then enters the carbon capture system, and the steam generated after the reaction is respectively input into the carbon capture system and the carbon dioxide refining system; The carbon capture system is connected to the carbon dioxide refining system and is used to generate carbon dioxide gas with a higher concentration from the gas after combustion treatment, and input it into the carbon dioxide refining system together with the raw gas; The carbon dioxide gasification system is connected to the carbon dioxide refining system and the carbon conversion system, and is used to convert the stored high-concentration liquid carbon dioxide into high-concentration carbon dioxide gas through a heat exchange system, and input it into the carbon conversion system to generate chemicals and fuels.

2. The carbon capture comprehensive utilization and energy recovery device according to claim 1, characterized in that: The carbon dioxide refining system includes a steam turbine compressor unit, a desulfurization tower, a purification tower, a precooler, a heat exchanger, a liquefier, a refrigeration system, a distillation tower and a storage tank connected in sequence. Through compression, desulfurization purification, cooling liquefaction and distillation processes, the higher concentration carbon dioxide gas is further purified and liquefied to obtain high-concentration liquid carbon dioxide and stored in a storage tank.

3. The carbon capture comprehensive utilization and energy recovery device according to claim 2, characterized in that: The gas oxidation treatment power generation system includes a gas turbine generator set, which includes a gas turbine, a compressor and an electric generator I. The compressor compresses the air and then undergoes an oxidation combustion reaction in the combustion chamber of the gas turbine together with the gas containing impurities discharged from the top of the distillation tower and storage tank in the carbon dioxide refining system. The high-temperature and high-pressure gas generated drives the electric generator I to generate electricity.

4. The carbon capture comprehensive utilization and energy recovery device according to claim 3, characterized in that: The device also includes a combustible gas replenishment system, which includes a compressor and a motor. The compressor pressurizes the combustible gas and then causes an oxidation combustion reaction to occur in the combustion chamber of the gas turbine together with the air compressed by the compressor and the gas containing impurities discharged from the top of the distillation tower and the storage tank. The high-temperature and high-pressure gas generated drives the electric generator I to generate electricity, and the generated electrical energy is used to power the motor.

5. The carbon capture, comprehensive utilization and energy recovery device according to claim 4, characterized in that: The impurity gases contained in the raw gas include but are not limited to hydrogen, hydrocarbons, nitrogen, and gases containing VOCs; the combustible gas is one or more streams of hydrocarbons, carbon monoxide or hydrogen gas; the combustion value of the gas entering the gas turbine should meet the requirements for combustion in the combustion chamber of the gas turbine.

6. The carbon capture, comprehensive utilization and energy recovery device according to claim 5, characterized in that: The heat recovery system is a waste heat boiler. The high-temperature gas exhausted by the gas turbine generates steam through the waste heat boiler and then enters the carbon capture system and the carbon dioxide refining system; the gas exhausted from the waste heat boiler enters the heat exchange system for heat exchange and then enters the carbon capture system.

7. The carbon capture, comprehensive utilization and energy recovery device according to claim 6, characterized in that: The carbon capture system comprises three processes of alkaline washing desulfurization, absorption and desorption to capture low-concentration carbon dioxide and concentrate it into higher-concentration carbon dioxide gas, wherein the alkaline washing desulfurization process adopts a pretreatment tower, the absorption process adopts an absorption tower, and the desorption process adopts a desorption tower; the pretreatment tower, the absorption tower and the desorption tower are connected in sequence; wherein the heat of the desorption tower is provided by the steam generated by the heat recovery system, the desorption tower is connected to a bottom reboiler, the steam is heat-exchanged through the bottom reboiler, and is used to heat the absorbent to realize desorption regeneration, and the condensed water after heat exchange is transported back to the heat recovery system.

8. The carbon capture, comprehensive utilization and energy recovery device according to claim 7, characterized in that: The carbon dioxide gasification system includes a pressure pump and a precooler. One side of the pressure pump is connected to the storage tank of the carbon dioxide refining system, and the other side is connected to the precooler. The precooler is connected to the heat exchange gasifier. The pressure pump is used to pressurize the stored liquid carbon dioxide to the required pressure, and to exchange heat with the gas discharged from the heat recovery system through the heat exchange gasifier, thereby reducing the temperature of the gas entering the carbon capture system and gasifying the liquid carbon dioxide into gas.

9. A method for comprehensive utilization of carbon capture and energy recovery, characterized in that: The method is carried out using the carbon capture comprehensive utilization and energy recovery device according to any one of claims 1 to 8, and comprises the following steps: S1. The raw gas is pressurized by a centrifugal compressor and then enters the desulfurization tower and purification tower. After desulfurization and purification, it passes through a precooler, a heat exchanger, and a liquefier in sequence and enters a distillation tower and a storage tank. Through compression, desulfurization and purification, cooling liquefaction and distillation processes, the high-concentration carbon dioxide gas is further purified and liquefied to obtain high-concentration liquid carbon dioxide and stored in a storage tank; S2. The gas containing impurities discharged from the top of the distillation tower and the storage tank enters the gas turbine of the gas oxidation treatment power generation system after passing through the heat exchanger, and undergoes oxidation combustion reaction with the air compressed by the compressor in the combustion chamber of the gas turbine. The high-temperature and high-pressure gas generated drives the compressor to pressurize the air, and the excess mechanical energy generated by the gas turbine drives the electric generator I to generate electricity; S3, the high temperature gas discharged from the gas turbine generates steam through the waste heat boiler and discharges the gas; S31, the gas discharged from the waste heat boiler is cooled by heat exchange in the heat exchange gasifier and enters the carbon capture system. The gas passes through the pretreatment tower, absorption tower and desorption tower in sequence, that is, the low-concentration carbon dioxide is captured and concentrated into a higher-concentration carbon dioxide gas through the alkaline washing desulfurization, absorption and desorption process; the higher-concentration carbon dioxide gas enters the carbon dioxide refining system, and then repeats the steps of S1 to store the high-concentration liquid carbon dioxide in the storage tank; S32. A portion of the steam generated by the waste heat boiler is provided to the desorption tower in the carbon capture system to heat the absorbent for desorption and regeneration, and the other portion is provided to the steam turbine compressor unit of the carbon dioxide refining system to generate mechanical energy to drive the centrifugal compressor to compress the carbon dioxide. The excess steam can be used to drive the electric generator II through the steam turbine to generate electricity and be provided to other electrical equipment in the system; S4. When preparing chemicals and fuels, the liquid carbon dioxide in the storage tank is converted into carbon dioxide gas through a pressure pump, a precooler, and a heat exchanger gasifier. The carbon dioxide gas is further converted into chemicals and fuels through a carbon conversion system.

10. The carbon capture comprehensive utilization and energy recovery method according to claim 9, characterized in that: In step S2, when the combustion value of the gas entering the gas turbine does not meet the combustion requirements in the combustion chamber of the gas turbine, combustible gas is introduced for supplementation. The pressurized combustible gas undergoes an oxidation combustion reaction in the combustion chamber of the gas turbine together with the air compressed by the compressor and the gas containing impurities discharged from the top of the distillation tower and the storage tank. The generated high-temperature and high-pressure gas drives the electric generator I to generate electricity. The generated electric energy is used to power the motor, and the excess electric energy is provided to other electrical equipment in the system.

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