Aromatic hydrocarbon synthesis system coupling direct air to capture CO2

Abstract

According to the aromatic hydrocarbon synthesis system for coupling direct air to capture CO2 provided by the invention, the heat exchanger is arranged to realize cyclic utilization of heat energy, reduce dependence of the calcining furnace on external energy and reduce use of non-renewable energy sources (such as natural gas), so that energy transformation is promoted, and the production cost is reduced. And heat loss in the system is effectively reduced by using the heat exchanger, and the overall energy utilization efficiency is improved.

Description

Technical Field

[0001] This application relates to the field of direct air capture CO2 technology, and more specifically, to an aromatics synthesis system coupled with direct air capture CO2. Background Technology

[0002] CO2 capture technologies primarily involve the decarbonization of fossil fuels before combustion or the separation of CO2 from combustion flue gas. However, given the increasing emissions from transportation and other distributed sources, capturing CO2 from ambient air is essential for achieving stable global CO2 concentrations in the atmosphere.

[0003] Currently implemented direct air capture (DAC) technologies are primarily limited by their high energy costs, as the heat is mainly provided by natural gas combustion, resulting in significant heat losses in process components such as preheaters, cyclone separators, and calciners. Furthermore, the use of non-renewable natural gas faces constraints related to resources, the environment, economics, and safety. To address these issues, it is necessary to promote energy transition, accelerate the shift to renewable and clean energy sources, and reduce energy consumption. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides an aromatics synthesis system coupled with direct air capture of CO2. By incorporating a heat exchanger, it achieves thermal energy recycling, reducing the calciner's dependence on external energy sources and decreasing the use of non-renewable energy sources (such as natural gas), thereby promoting energy transition and reducing energy costs. The use of the heat exchanger also effectively reduces internal heat loss, improving overall energy efficiency. This system not only captures CO2 but also converts it into a valuable aromatics mixture through chemical reactions, achieving resource utilization of CO2. The entire system reduces CO2 emissions, contributing to environmental protection and sustainable development.

[0005] This invention provides an aromatics synthesis system coupled with direct air capture of CO2, the system comprising: Air trap (1), first reactor (2), calcining furnace (3), electrolysis unit (4), heat exchanger (5), and second reactor (6); The outlet of the air trap (1) is connected to the inlet (21) of the first reactor (2), and the outlet (22) of the first reactor (2) is connected to the inlet of the calcining furnace (3). The outlet of the electrolysis device (4) is connected to a first outlet pipe (41), the outlet of the calcining furnace (3) is connected to the first outlet pipe (41), the end of the first outlet pipe (41) away from the electrolysis device (4) is connected to the first inlet (51) of the heat exchanger (5), the outlet of the heat exchanger (5) is connected to the second reactor (6), and the second inlet (52) of the heat exchanger (5) is connected to the calcining furnace (3). The air trap (1) contains a trapping agent and is configured to trap CO2 in the air with the trapping agent to obtain carbonates and water. The first reactor (2) stores Ca(OH)2 inside and is configured to react the carbonate with the Ca(OH)2 to obtain CaCO3 and the trapping agent; The calcining furnace (3) is configured to calcine the CaCO3 entering the calcining furnace (3) at a temperature greater than 800 °C to obtain CO2 and CaO; The electrolysis device (4) is used to electrolyze water to obtain hydrogen, and the hydrogen is discharged into the first outlet pipeline (41) along the outlet of the electrolysis device (4); The first outlet pipe (41) is configured to feed CO2 discharged from the outlet of the calcining furnace (3) and hydrogen discharged from the outlet of the electrolysis device (4) into the heat exchanger (5) through the first inlet (51). The heat exchanger (5) stores a heat storage medium and is configured to exchange heat between the heat storage medium and the CO2 and the hydrogen. After the CO2 and the hydrogen are cooled, they are transported to the second reactor (6). After the heat storage medium is heated, it is fed into the calcining furnace (3) through the second inlet (52). The heat storage medium is configured to heat the calcining furnace (3). The second reactor (6) is configured to carry out an aromatic synthesis reaction between the CO2 and the hydrogen to obtain an organic mixture; wherein the organic mixture includes an aromatic component, a light hydrocarbon component, water and coke.

[0006] Optionally, the heat storage medium is any one of magnesium oxide particles, aluminum oxide particles, and quartz sand particles; The heat storage medium heats the calcining furnace (3) to 400 ℃~500 ℃.

[0007] Optionally, the system further includes a heating device (31). The heating device (31) includes an electric arc heater (311); The electric arc heater (311) is connected to the calcining furnace (3), and the electric arc heater (311) is configured to be powered by renewable energy to heat the CaCO3; The renewable energy source can be any one of solar energy, wind energy, or biomass energy.

[0008] Optionally, the system further includes a synthesizer (7); The first inlet (71) of the synthesizer (7) is connected to the air trap (1), the second inlet (72) of the synthesizer (7) is connected to the calcining furnace (3), and the outlet of the synthesizer (7) is connected to the first reactor (2). The synthesizer (7) is configured to mix water discharged from the first inlet (71) with CaO discharged from the second inlet (72) to react and obtain Ca(OH)2, and then transport the Ca(OH)2 to the first reactor (2) for reuse.

[0009] Optionally, the capturing agent is NaOH or KOH.

[0010] Optionally, the temperature at which CO2 is obtained by calcining the CaCO3 is 800 ℃ to 1000 ℃.

[0011] Optionally, the temperature of the hydrogen gas obtained by the electrolysis device (4) from water electrolysis is 600 ℃~850 ℃.

[0012] Optionally, the system further includes a separator (8); The outlet of the second reactor (6) is connected to a second outlet pipe (61), and the inlet of the separator (8) is connected to the end of the second outlet pipe (61) away from the second reactor (6). The separator (8) is configured to separate the CO2 and hydrogen mixed in the organic mixture.

[0013] Optionally, the outlet of the separator (8) is connected to a third outlet pipeline (81), and a distillation column (811) is provided on the third outlet pipeline (81). The distillation column (811) is connected to the end of the third outlet pipeline (81) away from the separator (8); The distillation column (811) is configured to distill the separated organic mixture to obtain a product containing C at the top of the column. 6-8 The aromatic hydrocarbons of the component are obtained from the bottom of the column, and the aromatic hydrocarbons containing more than C9 components are output as products from the distillation column (811).

[0014] Optionally, the outlet of the distillation column (811) is connected to the second reactor (6) via a pipeline; The distillation column (811) is also configured to distill the C-containing column. 6-8 The aromatic hydrocarbons of the component are fed into the second reactor (6) for reuse.

[0015] Beneficial technical effects: This invention provides an aromatics synthesis system coupled with direct air capture of CO2. In this system, an air capture device is used to capture CO2 from the air and convert it into carbonates and water, thus achieving direct capture of CO2 from ambient air and helping to stabilize atmospheric CO2 concentration. Then, the carbonates react with Ca(OH)2 in a first reactor to generate CaCO3 and the capturing agent, achieving chemical fixation of CO2. The obtained capturing agent can be recycled. The resulting CaCO3 is calcined at high temperature in a calcining furnace to generate CO2 and CaO, releasing the CO2. This CO2 is then combined with hydrogen obtained from the electrolysis of water in an electrolysis device, and together with the CO2 discharged from the calcining furnace, provides the necessary feedstock for subsequent aromatics synthesis, achieving CO2 reuse. The heat exchanger utilizes a heat storage medium to exchange heat with CO2 and hydrogen. After cooling, the CO2 and hydrogen are fed into the second reactor, while the heat storage medium is heated and returned to the calcining furnace for reheating. This process significantly reduces heat loss during material transport, greatly improving energy efficiency and reducing dependence on non-renewable resources like natural gas by eliminating the step of burning natural gas. This promotes energy transition, accelerates the shift to renewable and clean energy, and reduces energy consumption. Finally, in the second reactor, CO2 and hydrogen undergo an aromatics synthesis reaction to produce an organic mixture, achieving the chemical conversion of CO2 and producing valuable chemicals. The entire system reduces CO2 emissions while producing environmentally friendly chemicals, contributing to environmental protection and sustainable development.

[0016] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A schematic diagram of an aromatics synthesis system coupled with direct air capture of CO2, as proposed in an embodiment of this application, is shown.

[0019] Explanation of reference numerals in the attached figures: 1. Air trap; 2. First reactor; 21. Inlet; 22. Outlet; 3. Calcination furnace; 31. Heating device; 311. Electric arc heater; 4. Electrolysis unit; 41. First outlet pipeline; 5. Heat exchanger; 51. First inlet; 52. Second inlet; 6. Second reactor; 61. Second outlet pipeline; 7. Synthesizer; 71. First inlet; 72. Second inlet; 8. Separator; 81. Third outlet pipeline; 811. Distillation column; 9. Hydrogenation reactor. Detailed Implementation

[0020] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0021] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0022] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0023] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0024] In the current field of CO2 capture technology, most technologies focus primarily on decarbonizing fossil fuels before combustion or separating CO2 from combustion flue gas. However, with the continuous increase in transportation and other distributed emission sources, relying solely on these traditional methods is insufficient to meet the demand for stable global CO2 concentrations. Therefore, direct CO2 capture from ambient air (DAC technology) has become a key approach to achieving atmospheric CO2 concentration control.

[0025] Despite the implementation of various DAC (Dielectric Degradation and Control) technologies, their widespread application remains limited by high energy costs. High-Temperature Water-Based DAC (HT DAC) technology, in particular, relies heavily on natural gas combustion for its heat demand. This not only results in significant heat losses in process components such as preheaters, cyclone separators, and calciners, but also presents multiple challenges related to natural gas use, including resource depletion, environmental pollution, economic costs, and safety risks. Addressing these technological challenges, promoting energy transition, and accelerating the shift to renewable and clean energy sources to reduce energy consumption have become crucial tasks.

[0026] In response to the problems existing in related technologies, this invention discovers that the aromatic hydrocarbon synthesis system is an innovative solution. It uses green raw materials and produces products with significant carbon emission reduction effects. It realizes multi-system collaborative operation of hydrogen energy industry, CCUS (carbon capture, utilization and storage) industry and chemical synthesis industry, and provides a new approach for CO2 capture and utilization.

[0027] Based on the above-mentioned inventive concept, this invention provides an aromatics synthesis system coupled with direct air capture of CO2, referring to... Figure 1 The system includes: Air trap 1, first reactor 2, calcining furnace 3, electrolysis device 4, heat exchanger 5, and second reactor 6; The outlet of the air trap 1 is connected to the inlet 21 of the first reactor 2, and the outlet 22 of the first reactor 2 is connected to the inlet of the calcining furnace 3. The outlet of the electrolysis device 4 is connected to a first outlet pipe 41, the outlet of the calcining furnace 3 is connected to the first outlet pipe 41, the end of the first outlet pipe 41 away from the electrolysis device 4 is connected to the first inlet 51 of the heat exchanger 5, the outlet of the heat exchanger 5 is connected to the second reactor 6, and the second inlet 52 of the heat exchanger 5 is connected to the calcining furnace 3. The air trap 1 contains a trapping agent and is configured to use the trapping agent to capture CO2 in the air to obtain carbonates and water. The first reactor 2 stores Ca(OH)2 inside, and the first reactor 2 is configured to react the carbonate with the Ca(OH)2 to obtain CaCO3 and the scavenging agent; The calcining furnace 3 is configured to calcine the CaCO3 entering the calcining furnace 3 at a temperature greater than 800 °C to obtain CO2 and CaO; The electrolysis device 4 is used to electrolyze water to obtain hydrogen, and the hydrogen is discharged into the first outlet pipeline 41 along the outlet of the electrolysis device 4. The first outlet pipe 41 is configured to mix CO2 discharged from the outlet of the calcining furnace 3 and hydrogen discharged from the outlet of the electrolysis device 4 and send it into the heat exchanger 5 along the first inlet 51. The heat exchanger 5 stores a heat storage medium and is configured to exchange heat between the heat storage medium and the CO2 and the hydrogen. After the CO2 and hydrogen are cooled, they are transported to the second reactor 6. After the heat storage medium is heated, it is fed into the calcining furnace 3 through the second inlet 52. The heat storage medium is configured to heat the calcining furnace 3. The second reactor 6 is configured to carry out an aromatic synthesis reaction between the CO2 and the hydrogen to obtain an organic mixture; wherein the organic mixture includes an aromatic component, a light hydrocarbon component, water, and coke.

[0028] It should be noted that the calcining furnace 3 can use renewable energy sources (such as solar and wind power) to generate electricity to raise the internal temperature of the calcining furnace 3, which helps to reduce dependence on traditional energy sources and promote the optimization of the energy structure. The capturing agent can be an alkaline solution. Capture refers to the reaction of an alkaline solution with CO2 to produce carbonates and water. Electrolysis device 4 can be an SOEC water electrolysis device, where SOEC refers to a solid oxide electrolysis cell, which is a technology that uses solid ion-conducting ceramic materials to decompose water into hydrogen and oxygen under high temperature conditions. In practical implementation, the system provided by this invention effectively captures CO2 from the atmosphere by setting up an air trap 1, converts it into CaCO3 through a chemical reaction, and then releases CO2 through calcination, achieving efficient capture and chemical conversion of CO2. During this process, the recycling of the capture agent and Ca(OH)2 ensures continuous CO2 capture. Combined with the heat exchanger 5, thermal energy (CO2 and hydrogen) can be recycled. Specifically, the high-temperature CO2 generated by the calcining furnace 3 and the hydrogen generated by water electrolysis exchange heat with the heat storage medium in the heat exchanger 5, lowering the temperature of CO2 and hydrogen and raising the temperature of the heat storage medium, which is then used to heat the calcining furnace 3, thereby improving energy utilization efficiency. Compared with related technologies, this avoids the process of burning non-renewable resources, thus greatly reducing the consumption of non-renewable energy. Furthermore, heating the calcining furnace 3 through the heat storage medium relatively reduces the heating energy required for the calcining furnace 3.

[0029] The system provided by this invention not only captures CO2 but also converts it into a valuable aromatic mixture through an aromatic synthesis reaction. In this process, CO2 is effectively utilized as a raw material, achieving resource recycling and value-added processing, and reducing CO2 emissions throughout the system. During the aromatic synthesis process, the reaction can proceed solely based on the heat generated by hydrogen and CO2 itself, eliminating the need for additional energy for heating and further reducing energy consumption.

[0030] In some embodiments, a fan may be provided at the air inlet of the air trap 1 to blow air into the air trap 1, thereby accelerating the airflow speed and allowing CO2 to come into contact with the trapping agent more quickly, thus improving the trapping efficiency.

[0031] In some embodiments, a nozzle, spray bottle, or other device capable of spraying a capture agent may be provided in the air trap 1 to make the capture agent in the air trap 1 in a spray form, so as to enhance the dispersion of the capture agent and enable the capture agent to contact CO2 at different locations in the air trap 1, thereby increasing the amount of CO2 captured.

[0032] In some embodiments, the outlet of the first reactor 2 is connected to the inlet of the air trap 1, and the first reactor 2 is also configured to deliver the generated trapping agent to the air trap 1 for reuse, so as to continuously replenish the trapping agent in the air trap 1 and enable CO2 capture to be carried out continuously.

[0033] In some embodiments, when the air trap 1 is equipped with a nozzle, sprayer or other device capable of spraying out the trapping agent, the outlet of the first reactor 2 is connected to the nozzle, sprayer or other device capable of spraying out the trapping agent, so that the recycled trapping agent can be sprayed into the air trap 1.

[0034] In some embodiments, refer to Figure 1The heat storage medium is any one of magnesium oxide particles, aluminum oxide particles, and quartz sand particles; The heat storage medium heats the calcining furnace 3 to 400 ℃~500 ℃.

[0035] In practice, the heat storage medium can heat the calcining furnace 3 to 400 ℃, 410 ℃, 420 ℃, 430 ℃, 440 ℃, 450 ℃, 460 ℃, 470 ℃, 408 ℃, 490 ℃, and 500 ℃.

[0036] This invention utilizes magnesium oxide, alumina, or quartz sand as the heat storage medium because these materials possess excellent thermal stability and heat storage performance, enabling them to effectively absorb and store thermal energy at high temperatures. When needed, the heat energy is slowly released, for example, to preheat the calcining furnace 3 to 400°C~500°C, thereby improving energy utilization efficiency and reducing heat loss during system operation. By rationally utilizing the thermal energy of the heat storage medium, the system can maintain the high-temperature operating environment of the calcining furnace 3 without relying on traditional fossil fuels (such as natural gas), thus reducing energy consumption and promoting energy transition and sustainable development. Simultaneously, the heat storage medium (such as magnesium oxide, alumina, and quartz sand) is an environmentally friendly material that does not pollute the environment, contributing to carbon emission reduction and environmental protection.

[0037] In practical implementation, the introduction of a thermal storage medium enables the system to store thermal energy during off-peak hours (i.e., the process of capturing CO2) and release thermal energy during peak hours (i.e., heat exchange with the thermal storage medium and mixing with hydrogen for aromatics synthesis) to meet production demands, thereby improving the system's operating efficiency and response speed. This invention combines CO2 capture with aromatics synthesis, realizing multi-system collaborative operation of the hydrogen energy industry, CCUS industry, and chemical synthesis industry. By capturing and utilizing CO2 from ambient air, it produces aromatics products with carbon emission reduction properties, improving the comprehensive utilization efficiency of resources.

[0038] In some embodiments, refer to Figure 1 The system also includes a heating device 31; The heating device 31 includes an electric arc heater 311; The electric arc heater 311 is connected to the calcining furnace 3, and the electric arc heater 311 is configured to be powered by renewable energy to heat the CaCO3; The renewable energy source can be any one of solar energy, wind energy, or biomass energy.

[0039] It should be noted that the electric arc heater 311, as a highly efficient energy conversion device, can directly convert electrical energy into heat energy for heating CaCO3 in the calcining furnace 3. The electric arc heater 311 has the characteristics of rapid heating and precise temperature control, which can quickly heat the calcining furnace 3 to the required temperature, thereby shortening the heating time, improving production efficiency, and reducing energy waste.

[0040] In practical implementation, this invention utilizes renewable energy sources such as solar, wind, and biomass energy to power the arc heater 311, achieving efficient utilization of renewable energy and reducing dependence on traditional fossil fuels. Because the arc heater 311 is powered by renewable energy, this solution significantly reduces carbon emissions compared to traditional heating methods that rely on fossil fuels. Addressing the intermittency and uncertainty of renewable energy sources (such as solar and wind power), the connection between the arc heater 311 and the calcining furnace 3 allows the system to be flexibly adjusted according to the availability of renewable energy. For example, when renewable energy is abundant, the power of the arc heater 311 can be increased to improve heating efficiency; when renewable energy is insufficient, the operating temperature of the calcining furnace 3 can be maintained by adjusting the power of the arc heater 311 or by utilizing a heat storage medium.

[0041] In some embodiments, refer to Figure 1 The system also includes a synthesizer 7; The first inlet 71 of the synthesizer 7 is connected to the air trap 1, the second inlet 72 of the synthesizer 7 is connected to the calcining furnace 3, and the outlet of the synthesizer 7 is connected to the first reactor 2. The synthesizer 7 is configured to mix water discharged from the first inlet 71 with CaO discharged from the second inlet 72 to react and obtain Ca(OH)2, and then transport the Ca(OH)2 to the first reactor 2 for reuse.

[0042] In practical implementation, by setting up a synthesizer 7, water and CaO are mixed and reacted to generate Ca(OH)2, thereby effectively utilizing the CaO produced in the calcining furnace 3. Furthermore, by recovering the moisture provided by the air trap 1, water resources are recycled, reducing resource waste and improving the overall system's resource utilization rate. The generated Ca(OH)2 is recycled back to the first reactor 2 to replenish its Ca(OH)2 content, allowing the reaction to proceed continuously. This invention, by setting up a synthesizer 7 in the system, effectively combines these two resources into valuable Ca(OH)2, reducing waste emissions, contributing to environmental protection, and lowering waste treatment costs.

[0043] In some embodiments, refer to Figure 1 The capturing agent is NaOH or KOH.

[0044] In practice, the capturing agent can be NaOH.

[0045] In this invention, NaOH and KOH, as strong bases, possess highly efficient CO2 capture capabilities. They can chemically react with CO2 in the air to generate corresponding carbonates, such as Na2CO3 or K2CO3, thereby achieving effective CO2 capture. Furthermore, these two strong bases react with CO2 at room temperature, requiring no additional heating or catalytic conditions. In addition, they are relatively insensitive to other impurities in the air (such as oxygen and nitrogen), thus enabling efficient CO2 capture and avoiding waste of capture agents.

[0046] In some embodiments, refer to Figure 1 The temperature at which CO2 is obtained by calcining the CaCO3 is 800 ℃~1000 ℃.

[0047] In practice, the temperature at which CO2 is obtained by calcining CaCO3 can be 800 ℃, 850 ℃, 900 ℃, 950 ℃, or 1000 ℃.

[0048] In this invention, the calcining furnace 3 is set at a temperature above 800 °C to calcine CaCO3, both to achieve efficient CO2 release and to obtain high-temperature CO2. This high-temperature CO2 can then undergo an aromatic addition reaction with hydrogen in the second reactor 6 without additional heating, producing an aromatic mixture containing more than C9 components, thus saving energy required for the aromatic addition reaction.

[0049] In some embodiments, refer to Figure 1 The temperature of the hydrogen gas obtained by electrolyzing water in the electrolysis device 4 is 600 ℃~850 ℃.

[0050] In specific implementation, the temperature of the hydrogen gas obtained by electrolyzing water in electrolysis device 4 can be 600 ℃, 650 ℃, 700 ℃, 750 ℃, 800 ℃, or 850 ℃.

[0051] In this invention, the high-temperature hydrogen generated during water electrolysis can be directly used to synthesize aromatics, and can also be used to store energy by exchanging heat with the heat storage medium through heat exchanger 5, so that the heat energy generated during electrolysis can be effectively utilized and energy waste can be avoided.

[0052] In some embodiments, refer to Figure 1 The system also includes a separator 8; The outlet of the second reactor 6 is connected to a second outlet pipe 61, and the inlet of the separator 8 is connected to the end of the second outlet pipe 61 that is away from the second reactor 6. The separator 8 is configured to separate the CO2 and hydrogen mixed in the organic mixture.

[0053] In specific implementation, in this invention, the organic mixture generated in the second reactor 6 contains unreacted CO2 and hydrogen. By setting up a separator 8, the unreacted CO2 and hydrogen are effectively separated from the organic mixture, thereby improving the purity of the product. The separated CO2 can be transported back to the second reactor 6 to continue participating in the reaction, preventing it from being emitted into the atmosphere.

[0054] In some embodiments, refer to Figure 1 The outlet of the separator 8 is connected to a third outlet pipe 81, and a distillation column 811 is installed on the third outlet pipe 81. The distillation column 811 is connected to the end of the third outlet pipeline 81 that is away from the separator 8; The distillation column 811 is configured to distill the separated organic mixture to obtain a product containing C at the top of the column. 6-8 The aromatic hydrocarbons of the component are obtained from the bottom of the column, and the aromatic hydrocarbons containing more than C9 components are output as products from the distillation column 811.

[0055] It should be noted that it contains C 6-8 The aromatic hydrocarbons in the composition mainly refer to hydrocarbon compounds whose molecules contain a benzene ring structure and have between 6 and 8 carbon atoms; for example, benzene (C6H6), toluene (C7H8), and xylene (C8H6). 10 Isomers such as o-xylene, m-xylene, and p-xylene, etc.; A mixture of aromatics containing more than one C9 component is also known as heavy aromatics, which refers to aromatics with a molecular weight greater than xylene (C8H1N2). 10 A mixture of aromatics, primarily consisting of C9 aromatics and aromatics with higher carbon numbers; for example, C10 aromatics (C9 aromatics, C ... 10 Aromatics, etc.; among which, C9 aromatics are one of the main components of heavy aromatics, accounting for about 80% to 90% of all reformed heavy aromatics, mainly composed of cumene, n-propylbenzene, ethyltoluene, indene, mesitylene, pseudotrimethylbenzene, terephthalene, etc. In specific implementation, the present invention first separates CO2 and hydrogen from the organic mixture by setting a separator 8. The organic mixture without CO2 and hydrogen is then transported to a distillation column 811 along the third outlet pipeline 81. The organic mixture undergoes further distillation treatment in the distillation column 811, and a product containing C is obtained at the top of the column. 6-8The distillation column yields aromatic hydrocarbons containing more than C9 components, while the bottom of the column contains aromatic hydrocarbons containing more than C9 components. By setting up distillation column 811, the purity of the product is increased, and the aromatic hydrocarbons containing C9 components are also removed. 6-8 The aromatics of the components are separated and recovered separately to avoid wasting useful components.

[0056] In some embodiments, refer to Figure 1 The outlet of the distillation column 811 is connected to the second reactor 6 via a pipeline; The distillation column 811 is also configured to distill the C-containing... 6-8 The aromatic hydrocarbons of the component are fed into the second reactor 6 for reuse.

[0057] In this invention, after separation by setting up a distillation column 811, the product containing C is... 6-8 The aromatic hydrocarbons of the components are separated separately and then returned to the second reactor 6 via pipeline as raw material for reuse. This not only reduces raw material waste but also improves raw material utilization, thereby reducing production costs. By reusing materials containing C... 6-8 The aromatic hydrocarbons in the components can also reduce the emission of unreacted raw materials, thereby reducing the risk of environmental pollution.

[0058] In some embodiments, refer to Figure 1 The system may also include a hydrogenation reactor 9, the inlet of which is connected to a distillation column 811.

[0059] By setting up a hydrogenation reactor 9, the aromatics containing more than C9 components output from the distillation column 811 are introduced into the hydrogenation reactor 9, and the reaction yields refined hydrocarbon products. After cooling, they are mixed with petroleum-based aviation kerosene in a certain proportion according to the product requirements, and finally formed sustainable aviation fuel.

[0060] To enable those skilled in the art to more clearly understand the present invention, the following embodiments will be used to provide a detailed description of an aromatics synthesis system coupled with direct air capture of CO2.

[0061] Example 1 (1) Under the action of natural airflow, air continuously flows into the air trap 1, comes into contact with NaOH, and generates Na2CO3 and water. The water enters the synthesizer 7 through the first inlet 71. (2) Na2CO3 enters the first reactor 2 through inlet 21 and reacts with Ca(OH)2 to generate CaCO3 and NaOH. NaOH is then returned to the air trap 1 to continue capturing CO2 in the air. (3) Start the electric arc heater 311 connected to the calcining furnace 3, use wind power to heat the inside of the calcining furnace 3 to 900 ℃, and then transport CaCO3 to the calcining furnace 3 through the outlet 22. Calcinate CaCO3 at 900 ℃ to obtain CO2 and CaO. (4) CaO is fed into synthesizer 7 through the second inlet 72, so that CaO reacts with water in synthesizer 7 to generate Ca(OH)2, which is then fed into the first reactor 2 through the outlet of synthesizer 7 to continue reacting with NaCO3. (5) Start the electrolysis device 4. Electrolysis of water produces hydrogen gas at a temperature of 750 °C. The hydrogen gas flows into the first outlet pipe 41 under the action of the airflow and is transported to the heat exchanger 5 to exchange heat with the quartz sand particles stored in the heat exchanger 5. The CO2 generated by the calcining furnace 3 flows into the first outlet pipe 41 under the action of the airflow and is transported to the heat exchanger 5 to exchange heat with the quartz sand particles stored in the heat exchanger 5, so that the temperature of the quartz sand particles rises to 450 °C and the hydrogen gas and CO2 cool down to 300 °C. (6) The heated quartz sand particles are conveyed to the calcining furnace 3 through the second inlet 52 to preheat the calcining furnace 3 before the next calcination of CaCO3, so that the temperature inside the calcining furnace 3 is raised to 425 °C. (7) The cooled CO2 and hydrogen are discharged into the second reactor 6 through the outlet of heat exchanger 5 to carry out the aromatic synthesis reaction and obtain an organic mixture; (8) The organic mixture obtained from the reaction enters the separator 8 through the second outlet pipe 61, where a small amount of hydrogen and CO2 are separated from the organic mixture and recovered. The separated organic mixture is then transported to the distillation column 811 through the third outlet pipe 81 for distillation treatment, wherein a product containing C is obtained at the top of the column. 6-8 The aromatic hydrocarbons of the component are obtained in the bottom of the column. The aromatic hydrocarbons containing more than C9 components are output as products from the distillation column 811. (9) At the top of the tower, a substance containing C was obtained. 6-8 After the aromatics of the component are discharged from the outlet of the distillation column 811, they are sent back to the second reactor 6 through the pipeline to continue to participate in the next aromatic synthesis reaction. (10) The above processes are performed separately during system operation until the system stops running.

[0062] In summary, this invention provides an aromatics synthesis system coupled with direct air capture of CO2. By incorporating a heat exchanger, it achieves thermal energy recycling, reducing the calciner's dependence on external energy sources and decreasing the use of non-renewable energy sources (such as natural gas), thereby promoting energy transition and reducing energy costs. The use of the heat exchanger also effectively reduces internal heat loss, improving overall energy efficiency. This system not only captures CO2 but also converts it into a valuable aromatics mixture through chemical reactions, achieving resource utilization of CO2. The entire system reduces CO2 emissions, contributing to environmental protection and sustainable development.

[0063] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0064] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0065] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0066] The above provides a detailed description of an aromatics synthesis system coupled with direct air capture of CO2 provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An aromatics synthesis system coupled with direct air capture of CO2, characterized in that, The system includes: Air trap (1), first reactor (2), calcining furnace (3), electrolysis unit (4), heat exchanger (5), and second reactor (6); The outlet of the air trap (1) is connected to the inlet (21) of the first reactor (2), and the outlet (22) of the first reactor (2) is connected to the inlet of the calcining furnace (3). The outlet of the electrolysis device (4) is connected to a first outlet pipe (41), the outlet of the calcining furnace (3) is connected to the first outlet pipe (41), the end of the first outlet pipe (41) away from the electrolysis device (4) is connected to the first inlet (51) of the heat exchanger (5), the outlet of the heat exchanger (5) is connected to the second reactor (6), and the second inlet (52) of the heat exchanger (5) is connected to the calcining furnace (3). The air trap (1) contains a trapping agent and is configured to trap CO2 in the air with the trapping agent to obtain carbonates and water. The first reactor (2) stores Ca(OH)2 inside and is configured to react the carbonate with the Ca(OH)2 to obtain CaCO3 and the trapping agent; The calcining furnace (3) is configured to calcine the CaCO3 entering the calcining furnace (3) at a temperature greater than 800 °C to obtain CO2 and CaO; The electrolysis device (4) is used to electrolyze water to obtain hydrogen, and the hydrogen is discharged into the first outlet pipeline (41) along the outlet of the electrolysis device (4); The first outlet pipe (41) is configured to feed CO2 discharged from the outlet of the calcining furnace (3) and hydrogen discharged from the outlet of the electrolysis device (4) into the heat exchanger (5) through the first inlet (51). The heat exchanger (5) stores a heat storage medium and is configured to exchange heat between the heat storage medium and the CO2 and the hydrogen. After the CO2 and the hydrogen are cooled, they are transported to the second reactor (6). After the heat storage medium is heated, it is fed into the calcining furnace (3) through the second inlet (52). The heat storage medium is configured to heat the calcining furnace (3). The second reactor (6) is configured to carry out an aromatic synthesis reaction between the CO2 and the hydrogen to obtain an organic mixture; wherein the organic mixture includes an aromatic component, a light hydrocarbon component, water and coke.

2. The aromatics synthesis system coupled with direct air capture of CO2 according to claim 1, characterized in that, The heat storage medium is any one of magnesium oxide particles, aluminum oxide particles, and quartz sand particles. The heat storage medium heats the calcining furnace (3) to 400 ℃~500 ℃.

3. The aromatics synthesis system coupled with direct air capture of CO2 according to claim 1, characterized in that, The system also includes a heating device (31); The heating device (31) includes an electric arc heater (311); The electric arc heater (311) is connected to the calcining furnace (3), and the electric arc heater (311) is configured to be powered by renewable energy to heat the CaCO3; The renewable energy source can be any one of solar energy, wind energy, or biomass energy.

4. The aromatics synthesis system coupled with direct air capture of CO2 according to claim 1, characterized in that, The system also includes a synthesizer (7); The first inlet (71) of the synthesizer (7) is connected to the air trap (1), the second inlet (72) of the synthesizer (7) is connected to the calcining furnace (3), and the outlet of the synthesizer (7) is connected to the first reactor (2). The synthesizer (7) is configured to mix water discharged from the first inlet (71) with CaO discharged from the second inlet (72) to react and obtain Ca(OH)2, and then transport the Ca(OH)2 to the first reactor (2) for reuse.

5. The aromatics synthesis system coupled with direct air capture of CO2 according to claim 1, characterized in that, The capturing agent is NaOH or KOH.

6. The aromatics synthesis system coupled with direct air capture of CO2 according to claim 1, characterized in that, The temperature at which CO2 is obtained by calcining the CaCO3 is 800 ℃~1000 ℃.

7. The aromatics synthesis system coupled with direct air capture of CO2 according to claim 1, characterized in that, The temperature of the hydrogen gas obtained by electrolyzing water in the electrolysis device (4) is 600 ℃~850 ℃.

8. The aromatics synthesis system coupled with direct air capture of CO2 according to any one of claims 1-7, characterized in that, The system also includes a separator (8); The outlet of the second reactor (6) is connected to a second outlet pipe (61), and the inlet of the separator (8) is connected to the end of the second outlet pipe (61) away from the second reactor (6). The separator (8) is configured to separate the CO2 and hydrogen mixed in the organic mixture.

9. The aromatics synthesis system coupled with direct air capture of CO2 according to claim 8, characterized in that, The outlet of the separator (8) is connected to a third outlet pipeline (81), and a distillation column (811) is provided on the third outlet pipeline (81). The distillation column (811) is connected to the end of the third outlet pipeline (81) away from the separator (8); The distillation column (811) is configured to distill the separated organic mixture to obtain a product containing C at the top of the column. 6-8 The aromatic hydrocarbons of the component are obtained from the bottom of the column, and the aromatic hydrocarbons containing more than C9 components are output as products from the distillation column (811).

10. The aromatics synthesis system coupled with direct air capture of CO2 according to claim 9, characterized in that, The outlet of the distillation column (811) is connected to the second reactor (6) via a pipeline; The distillation column (811) is also configured to distill the C-containing column. 6-8 The aromatic hydrocarbons of the component are fed into the second reactor (6) for reuse.

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