Device for hydrogenation of carbon dioxide to methanol combined with chemical looping combustion and preparation method thereof

Abstract

The application belongs to the technical field of methanol preparation, and particularly relates to a device and a preparation method for preparing methanol by combining carbon dioxide hydrogenation with chemical chain combustion, which comprises a power generation system, an electrolytic cell, a chemical chain combustion reactor, a pure oxygen supplement combustion chamber and a methanol reaction unit. The power generation system is connected with the electrolytic cell. Oxygen generated by electrolysis of the electrolytic cell is connected with the chemical chain combustion reactor through a first pipeline. Oxygen generated by electrolysis of the electrolytic cell is connected with the pure oxygen supplement combustion chamber through a second pipeline. The chemical chain combustion reactor is connected with a raw material pipeline. The top of the chemical chain combustion reactor is connected with the pure oxygen supplement combustion chamber through a third pipeline. The pure oxygen supplement combustion chamber is connected with the methanol reaction unit through a fourth pipeline. Hydrogen generated by electrolysis of the electrolytic cell is connected with the methanol reaction unit through a fifth pipeline. Reaction products are discharged through a sixth pipeline.

Description

Technical Field

[0001] This invention belongs to the field of methanol preparation technology, specifically, it relates to an apparatus and preparation method for producing methanol by carbon dioxide hydrogenation combined with chemical looping combustion. Background Technology

[0002] Methanol is an important chemical product, a raw material for many high-value-added chemicals, and a crucial solvent in organic chemistry. As a widely used basic chemical raw material and high-quality fuel, methanol can not only be used to produce chemicals such as aromatics and olefins, but also directly as fuel for fuel cells. Methanol plays a vital role in industries such as pharmaceuticals, fuels, plastics, and synthetic fibers. Nobel laureate in physics, Karolubia, has repeatedly proposed using carbon dioxide hydrogenation to produce methanol, achieving carbon dioxide emission reduction while providing a basic industrial raw material. Another Nobel laureate, George Andrew Euler, proposed in his work that a circular model of renewable energy-based hydrogen production and carbon dioxide hydrogenation to methanol production is a way to solve the energy shortage problem after the oil and gas era. By coupling carbon dioxide capture technology with green hydrogen production technology, industrially mandated carbon dioxide emissions can be recycled. Large-scale green methanol can not only be used directly or indirectly as fuel to alleviate China's liquid fuel shortage, but also serve as a hydrogen carrier, solving the safety and cost issues of hydrogen production, storage, and transportation. It provides a feasible technical route for solving the large-scale storage and peak load balancing problems of intermittent energy sources such as wind and solar power, connecting multiple industries in a carbon-neutral green economic ecosystem.

[0003] However, current carbon dioxide hydrogenation to methanol processes have several problems. First, there is no reasonable method for disposing of the pure oxygen obtained during water electrolysis to produce hydrogen. Second, to achieve emission reduction goals, the carbon dioxide used as a raw material is often the exhaust gas from fossil fuel combustion. Conventional combustion exhaust gases contain a large amount of nitrogen, which dilutes the carbon dioxide, making its purity insufficient for subsequent value-added processing. This necessitates adding a complex and difficult nitrogen-carbon dioxide separation step. Furthermore, the energy waste and pollutant emissions caused by conventional combustion methods contradict the purpose of using carbon dioxide hydrogenation to produce methanol. Summary of the Invention

[0004] In view of the above-mentioned defects of existing methods, the present invention provides an apparatus and preparation method for producing methanol by carbon dioxide hydrogenation combined with chemical looping combustion, which solves the technical problems of low methanol purity, complex process and environmental unfriendly nature of existing technologies.

[0005] According to a first aspect of the present invention, an apparatus for producing methanol by carbon dioxide hydrogenation in conjunction with chemical looping combustion is provided, comprising a power generation system, an electrolytic cell, a chemical looping combustion reactor, a pure oxygen combustion chamber, and a methanol reaction unit. The power generation system is connected to the electrolytic cell, the electrolytic cell is connected to the chemical looping combustion reactor via a first pipeline, the electrolytic cell is connected to the pure oxygen combustion chamber via a second pipeline, the chemical looping combustion reactor is connected to a raw material pipeline, the top of the chemical looping combustion reactor is connected to the pure oxygen combustion chamber via a third pipeline, the pure oxygen combustion chamber is connected to the methanol reaction unit via a fourth pipeline, the hydrogen generated by electrolysis in the electrolytic cell is connected to the methanol reaction unit via a fifth pipeline, and the methanol reaction unit is connected to a sixth pipeline.

[0006] Preferably, the chemical looping combustion reactor includes a fuel reactor, a first cyclone separator, a second cyclone separator, an air reactor, a first flow sealing valve, and a second flow sealing valve; the fuel reactor is connected to the first pipeline, the top of the fuel reactor is connected to the top of the air reactor through the first cyclone separator, and the top of the fuel reactor is also connected to the top of the pure oxygen combustion chamber through the second cyclone separator; the bottom of the fuel reactor is connected to the bottom of the air reactor through the first flow sealing valve, and the bottom of the fuel reactor is also connected to the bottom of the second cyclone separator through the second flow sealing valve; the top of the air reactor is connected to a seventh pipeline, the bottom of the air reactor is connected to an air pipeline, and the top of the second cyclone separator is connected to a third pipeline.

[0007] Preferably, a condenser is connected to the fourth pipeline, and the condenser is connected to the electrolytic cell via an eighth pipeline.

[0008] Preferably, the methanol reaction unit comprises: a first heat exchanger, a fixed-bed reactor, a first flash evaporator, a second flash evaporator, a fractionator, and a third flash evaporator connected in sequence; the second pipeline is connected to the fourth pipeline and the ninth pipeline; the ninth pipeline is connected to the first heat exchanger; the tops of the first flash evaporator, the second flash evaporator, and the third flash evaporator are respectively connected to the ninth pipeline via the tenth pipeline, the eleventh pipeline, and the twelfth pipeline; and the first heat exchanger is connected to the seventh pipeline.

[0009] Preferably, the raw material pipeline is used to introduce biomass, and the fuel reactor is loaded with an oxygen carrier selected from one or more of Fe2O3, CuO, NiO, Mn2O3, CaSO4, BaSO4, CaFe2O5, CuFe2O4, and perovskite; the biomass is selected from one or more of sawdust, straw, and rice husk.

[0010] Preferably, the pure oxygen combustion chamber is filled with a mixture of elements or compounds containing noble metals or non-noble metals and Fe2O3, CuO, NiO, Mn2O3, CO3O4, and perovskite as a catalyst, wherein the noble metal is selected from Ag, Pd, Pt, Au, Rh, and Ir; and the non-noble metal is selected from Mn, Ce, and Sr; the fixed-bed reactor is filled with a methanol synthesis catalyst, wherein the methanol synthesis catalyst is selected from one or more of Cu and Pd.

[0011] According to another aspect of the present invention, a method for preparing methanol using an apparatus for producing methanol by carbon dioxide hydrogenation combined with chemical looping combustion is provided, comprising the following steps:

[0012] (1) Power is supplied to the electrolytic cell through a power generation system. The electrolytic cell electrolyzes water to produce hydrogen and oxygen.

[0013] (2) Introduce biomass, oxygen carrier and oxygen generated by electrolysis of water with a volume fraction of 80-90% into the bottom of the chemical looping combustion reactor;

[0014] (3) The gas produced after the reaction in step (2) is introduced into the pure oxygen combustion chamber along with the oxygen produced by electrolysis of water with a volume fraction of 10-20%. Under the action of the catalyst, the reaction is further carried out to completely convert the biomass into carbon dioxide gas.

[0015] (4) The carbon dioxide and hydrogen obtained by electrolysis of water are used to form a raw material gas, and the raw material gas is passed into the methanol reaction unit to obtain methanol.

[0016] Preferably, step (2) specifically involves feeding biomass into a fuel reactor containing an oxygen carrier for reaction, and separating the gas produced by the reaction into gas and solid phases through a second cyclone separator. The separated gas phase is fed into a pure oxygen combustion chamber for further reaction, and the separated solid phase is returned to the fuel reactor through a second flow sealing valve. The oxygen carrier at the bottom of the fuel reactor enters the bottom of the air reactor through a first flow sealing valve, and after being fully mixed with the air fed into the air reactor, it enters the first cyclone separator for gas-solid separation. The separated solid is the oxidized oxygen carrier, which falls into the fuel reactor to achieve circulation.

[0017] Preferably, step (4) specifically involves introducing the raw material gas into the first heat exchanger, where the exhaust gas from the air reactor generated in the air reactor exchanges heat with the raw material gas in the first heat exchanger to raise the temperature of the raw material gas and maintain the temperature of the raw material gas at 200-300°C. The heated raw material gas is then sequentially introduced into the fixed bed reactor, the first flash reactor, the second flash reactor, the fractionator, and the third flash reactor for full reaction. The third flash reactor flashes to produce the liquid product methanol, and the gaseous products produced by the reactions in the first flash reactor, the second flash reactor, and the third flash reactor are returned to the raw material gas for further full reaction.

[0018] Preferably, the carbon dioxide gas generated in step (3) is condensed by a condenser, and the resulting condensate is fed into the electrolytic cell.

[0019] In summary, compared with the prior art, the above-described technical solutions conceived by this invention mainly possess the following technical advantages:

[0020] 1. This invention uses a chemical looping combustion method to burn biomass to obtain carbon dioxide, avoiding direct contact between air and biomass. This allows biomass to be directly converted into high-concentration carbon dioxide without being affected by nitrogen dilution, resulting in high-purity methanol that is free of byproducts such as nitrogen oxides and sulfur oxides.

[0021] 2. This invention employs a chemical looping combustion reactor for biomass oxidation. Biomass oxidation typically produces some sulfur oxides and nitrogen oxides. However, in chemical looping combustion, firstly, the temperature and component distribution are more uniform, and the unique low-O2, reducing atmosphere helps reduce most of the fuel nitrogen to N2. Furthermore, the lower temperature suppresses rapid and thermal NOx formation. x SO is generated and can be removed in situ by CaO, etc. x Therefore, the levels of sulfur oxides and nitrogen oxides in chemical looping combustion are significantly lower.

[0022] 3. This invention uses an oxygen carrier, taking Fe2O3 as an example, which contains O 2- This oxygen, known as lattice oxygen, is reduced to the lower valence state of Fe3O4 during the reaction of Fe2O3 with fuel gas in the fuel reactor. In this process, lattice oxygen is consumed, and the oxygen carrier is reduced. After reduction, the oxygen carrier enters the air reactor, which is separated from the fuel reactor by a cyclone separator and a flow-sealed valve. Only the oxygen carrier is exchanged, with minimal gas exchange. In the air reactor, the oxygen carrier reacts with the incoming air, and FeO is re-oxidized to Fe3O4, replenishing the lattice oxygen. The replenished oxygen carrier then returns to the fuel reactor to continue reacting with fuel gas, providing more lattice oxygen. Thus, macroscopically, the metal oxide plays a role in converting gaseous oxygen in the air into lattice oxygen, which is then transported back to the fuel reactor for recycling.

[0023] 4. The methanol reaction device of the present invention utilizes the advantages of the three-stage flash evaporation technology. When using a relatively inexpensive and inefficient catalyst, it can effectively separate the gas phase component containing unreacted raw material gas and by-products, while enriching the liquid phase component containing methanol. By reintroducing the gas phase product into the reactor for reaction, the CO2, CO and H2 in the gas phase product will continuously react in the circulation loop, improving the raw material utilization rate and reducing the generation of by-products. As a result, the carbon dioxide conversion rate and methanol selectivity in the overall process flow both exceed 99%.

[0024] 5. This invention utilizes pure oxygen obtained from water electrolysis to further convert the chemical loop combustion exhaust gas in a pure oxygen combustion chamber, achieving the utilization of pure oxygen. Simultaneously, after further oxidation, biomass is completely converted into carbon dioxide. Condensation treatment removes water vapor from the carbon dioxide, yielding high-purity carbon dioxide gas, which can be used as a raw material for methanol production. The condensed water is then added to the electrolytic cell as a raw material, achieving material recycling and improving utilization efficiency. This invention also utilizes the high-temperature flue gas generated during chemical loop combustion as a heat source. A first heat exchanger heats the hydrogen and carbon dioxide feed gas, raising their temperature and maintaining the temperature of the carbon dioxide hydrogenation to methanol system, thus achieving efficient utilization of thermal energy.

[0025] 6. The entire method of this invention only requires biomass and green electricity as input carbon sources to obtain green methanol. It integrates multiple subsystems such as electrolysis cell, chemical looping combustion, and carbon dioxide hydrogenation to methanol production to form a stable and feasible energy flow cycle, achieving multi-subsystem coupling, high efficiency, and carbon-negative methanol production, realizing the resource utilization of waste, and generating no other waste gas. Therefore, the methanol production method of this invention is completely green. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the carbon dioxide hydrogenation to methanol process system that combines chemical looping combustion according to the present invention.

[0027] Figure 2 This is a schematic diagram of the methanol reaction unit of the present invention.

[0028] Figure 3 The yield of each component in the exhaust gas from the biomass chemical loop combustion reactor of this invention is given.

[0029] Figure 4 The conversion rate of each component in the exhaust gas from the pure oxygen combustion chamber of this invention is given.

[0030] In the diagram, 1 is the power generation system; 2 is the electrolytic cell; 3 is the chemical looping combustion reactor; 4 is the pure oxygen combustion chamber; 5 is the methanol reaction unit; 6 is the condenser; 101 is the first pipeline; 102 is the fifth pipeline; 111 is the second pipeline; 104 is the raw material pipeline; 105 is the third pipeline; 106 is the air pipeline; 107 is the seventh pipeline; 108 is the eighth pipeline; 109 is the fourth pipeline; 110 is the sixth pipeline; 31 is the fuel reactor; 32 is the first cyclone separator; 33 is the air reactor; 34 is the first flow sealing valve; 35 is the second cyclone separator; 36 is the second flow sealing valve; 5A is the first heat exchanger; 5B is the fixed bed reactor; 5C is the first flash evaporator; 5D is the second flash evaporator; 5E is the fractionator; 5F is the third flash evaporator; 501 is the ninth pipeline; 502 is the tenth pipeline; 503 is the eleventh pipeline; 504 is the twelfth pipeline. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0032] Example 1

[0033] Please see Figure 1 and Figure 2 A process system for producing methanol from carbon dioxide via chemical looping combustion, specifically including:

[0034] Solar panel 1, as a photovoltaic power generation system, is continuously subjected to a temperature of 25℃ and a power output of 1000W / m². 2 Under the intensity of sunlight radiation, it outputs 7V, 20A DC power.

[0035] The photovoltaic power generation system outputs direct current, which is fed into a proton exchange membrane electrolyzer 2. The electrolyzer uses a proton exchange membrane to electrolyze water to produce hydrogen and oxygen. The electrolyzer uses precious metals as catalysts; the catalyst size of a single electrolyzer is 40*50 mm, with a hydrogen production rate of 350 mL / min and an oxygen production rate of 175 mL / min. The purity of the gas obtained from electrolysis is higher than 99.99%. Multiple electrolyzers are integrated to achieve large-scale hydrogen and oxygen production.

[0036] The chemical looping combustion reactor 3 is a circulating fluidized bed reactor. The fuel reactor 31 is a bubbling fluidized bed filled with Fe2O3. 90% vol pure oxygen obtained from water electrolysis is introduced into the fuel reactor 31 from the bottom through the first pipe 101. Biomass pellets are continuously supplied to the fuel reactor 31 through the feed pipe 104. In the fuel reactor 31, the large amount of sensible heat carried by the oxygen carrier from the air reactor, combined with the reaction heat in the fuel reactor, raises the reactor temperature to 950°C. The biomass pellets first react with the pure oxygen introduced through the first pipe 101 to produce fuel gas, which then undergoes a redox reaction with the oxygen carrier packed in the fuel reactor.

[0037] A first cyclone separator 32 is installed at the top of the fuel reactor 31. The reaction products in the fuel reactor 31 enter the first cyclone separator 32 for gas-solid separation. The separated solid component is Fe3O4 oxygen carrier in a reduced state, which falls into the second flow sealing valve 36. The separated fuel reaction gas tail gas is discharged from the third pipeline 105. After removing a small amount of escaped particles, the CO2 yield from the chemical loop combustion with water reaches 98.0%, while exhibiting low CO (0.8%) and CH4 yields (1.2%). The carbon capture efficiency is maintained at 98%, and the biomass combustion efficiency reaches 95.5%. The results are as follows: Figure 3 As shown.

[0038] Air reactor 33 is in a rapid fluidized bed state. The reduced oxygen carrier at the bottom of fuel reactor 31 returns to the bottom of air reactor 33 through the first flow sealing valve 34. Air is introduced through air pipe 106, and the air oxidizes the reduced oxygen carrier to the oxidized state. A large amount of heat is released in the process. The oxidized oxygen carrier enters the first cyclone separator 32. After gas-solid separation, it re-enters fuel reactor 31 at a mass flow rate of 38.5 kg / s to achieve oxygen carrier circulation. Only oxygen carrier is exchanged in the first flow sealing valve 34, and there is no gas exchange. A large amount of heat is released in air reactor 33, and the exhaust gas of air reactor with a temperature of 1000°C is discharged through the seventh pipe 107 after gas-solid separation in air reactor 33.

[0039] The pure oxygen combustion chamber 4 is filled with 500g of SrTiO3-modified Fe2O3 catalyst. Fuel reactor exhaust gas is introduced into the pure oxygen combustion chamber 4 through the third pipe 105. Simultaneously, 10% vol of pure oxygen obtained from water electrolysis is added to the pure oxygen combustion chamber 4 through the second pipe 111. Combustion is complete at 1050℃ under the action of the catalyst. The condensed outlet gas yields CO2 with a purity of over 99%, which is discharged through the fourth pipe 109. The condensed water is recycled into the electrolytic cell 2 through the eighth pipe 108. Under long-term experimental conditions (over 10800s) at a reaction temperature of 800℃ and an air-fuel ratio of 1.1, the stable operation of the pure oxygen combustion chamber 4 resulted in a CO conversion rate of 98.4%, a CH4 conversion rate of 99.4%, and a H2 conversion rate of 100%, achieving a combustion efficiency of 99.2%. After removing water vapor and N2 used for balancing, the CO2 content at the outlet of the deoxygenated combustion chamber is 99.9%, as shown in the following figures. Figure 4 As shown, experimental results demonstrate that at 800℃, with 10% pure oxygen input into the electrolyzed water, the pure oxygen combustion chamber can achieve complete conversion of unburned gases from chemical looping combustion, yielding CO2 with a concentration of over 99.9%. This CO2 can be used as a feedstock for the hydrogenation of carbon dioxide to methanol.

[0040] High-purity CO2 enters the fourth pipe 109 and H2 enters the ninth pipe 501 through the fifth pipe 102 to obtain a mixed gas. The mixed gas enters the first heat exchanger 5A through the ninth pipe 501 and is preheated to 250°C by the exhaust gas from the air reactor discharged through the seventh pipe 107. It is then introduced into the fixed-bed reactor 5B containing a Cu catalyst for reaction. After the reaction, the gas is separated into liquid and vapor products by the first flash evaporator 5C. The liquid products enter the second flash evaporator 5D and are flashed and separated into liquid and vapor products again. The vapor products separated by the first and second flash evaporations are collected and mixed with the raw gas. After being preheated again by the ninth pipe 501, they are introduced into the fixed-bed reactor 5B for recycling. The liquid product generated in the second flash evaporator 5D contains unreacted CO2, H2 and byproduct CO. It enters the fractionator 5E for fractionation. The liquid product obtained by fractionation is methanol. The gaseous product enters the third flash evaporator 5L for flash evaporation again. The liquid product obtained by the third flash evaporation is methanol. The gaseous product is recycled back to the ninth pipeline 501 for reuse.

[0041] An Aspen Plus full-process simulation model of a carbon dioxide hydrogenation to methanol process coupled with chemical looping combustion was constructed. The resulting logistics are as follows: 50 t / d of imported biomass was used. The O2 produced during water electrolysis to produce hydrogen was 1.1838 kg / s. 1.06542 kg / s of pure O2 was then fed into the chemical looping combustion unit to assist in the chemical looping combustion of the biomass, achieving a combustion efficiency of over 95%. Then, 0.11838 kg / s of pure O2 was introduced into the oxygen-assisted combustion chamber, achieving a combustion efficiency of over 99%. The outlet gas from the oxygen-assisted combustion chamber was condensed to obtain 1.08947 kg / s of CO2 with a purity of 99.63% (with trace amounts of N2 and H2O as impurities) and 0.386126 kg / s of H2O. The condensate, along with 0.946831 kg / s of makeup water, is fed into an electrolytic cell for electrolysis, yielding 1.1838 kg / s of high-purity O2 and 0.149155 kg / s of high-purity H2. This H2, along with CO2, is then fed into a carbon dioxide hydrogenation reactor to produce methanol at a reaction temperature of 250°C, ultimately yielding 0.7715 kg / s of methanol with a purity of 99.19%. Both the material and energy flows are balanced. Under these conditions, the biomass carbon conversion rate reaches 99.99%, the carbon capture efficiency reaches 99%, the CO2 conversion rate reaches 98%, and the methanol selectivity reaches 99%.

[0042] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An apparatus for producing methanol by hydrogenation of carbon dioxide combined with chemical looping combustion, characterized in that, The system includes a power generation system (1), an electrolytic cell (2), a chemical looping combustion reactor (3), a pure oxygen combustion chamber (4), and a methanol reaction unit (5). The power generation system (1) is connected to the electrolytic cell (2). The electrolytic cell (2) is connected to the chemical looping combustion reactor (3) via a first pipeline (101). The electrolytic cell (2) is connected to the pure oxygen combustion chamber (4) via a second pipeline (111). The chemical looping combustion reactor (3) is connected to the raw material pipeline (104). The top of the reactor (3) is connected to the pure oxygen combustion chamber (4) via a third pipe (105). The pure oxygen combustion chamber (4) is connected to the methanol reaction unit (5) via a fourth pipe (109). The hydrogen generated by the electrolysis of the electrolytic cell (2) is connected to the methanol reaction unit (5) via a fifth pipe (102). The methanol reaction unit (5) is connected to the sixth pipe (110). The pure oxygen combustion chamber (4) is filled with elements or compounds containing precious metals or non-precious metals and Fe2O. 3、 A mixture of CuO, NiO, Mn2O3, Co3O4, and perovskite is used as a catalyst, wherein the noble metal is selected from Ag, Pd, Pt, Au, Rh, and Ir; and the non-noble metal is selected from Mn, Ce, and Sr. The raw material pipeline (104) is used to introduce biomass, wherein the biomass is selected from one or more of sawdust, straw, and rice husk. The chemical loop combustion reactor (3) includes a fuel reactor (31), a first cyclone separator (32), a second cyclone separator (35), an air reactor (33), a first flow sealing valve (34), and a second flow sealing valve (36). The fuel reactor (31) is connected to the first pipeline (101), and the top of the fuel reactor (31) is connected to the top of the air reactor (33) through the first cyclone separator (32). The top of the fuel reactor (31) is also connected to pure oxygen supplementation through the second cyclone separator (35). The top of the combustion chamber (4) is connected; the bottom of the fuel reactor (31) is connected to the bottom of the air reactor (33) through the first flow sealing valve (34), the bottom of the fuel reactor (31) is also connected to the bottom of the second cyclone separator (35) through the second flow sealing valve (36), the top of the air reactor (33) is connected to the seventh pipeline (107), the bottom of the air reactor (33) is connected to the air pipeline (106), and the top of the second cyclone separator (35) is connected to the third pipeline (105).

2. The apparatus for producing methanol from carbon dioxide via chemical looping combustion according to claim 1, characterized in that, The fourth pipeline (109) is connected to the condenser (6), and the condenser (6) is connected to the electrolytic cell (2) through the eighth pipeline (108).

3. The apparatus for producing methanol from carbon dioxide via chemical looping combustion according to claim 1, characterized in that, The methanol reaction unit (5) is specifically composed of: a first heat exchanger (5A), a fixed-bed reactor (5B), a first flash evaporator (5C), a second flash evaporator (5D), a fractionator (5E), and a third flash evaporator (5F) connected in sequence. The fifth pipeline (102) and the fourth pipeline (109) are connected to the ninth pipeline (501). The ninth pipeline (501) is connected to the first heat exchanger (5A). The tops of the first flash evaporator (5C), the second flash evaporator (5D), and the third flash evaporator (5F) are connected to the ninth pipeline (501) through the tenth pipeline (502), the eleventh pipeline (503), and the twelfth pipeline (504), respectively. The first heat exchanger (5A) is connected to the seventh pipeline (107).

4. The apparatus for producing methanol from carbon dioxide via chemical looping combustion according to claim 1, characterized in that, The fuel reactor (31) is internally loaded with an oxygen carrier selected from one or more of Fe2O3, CuO, NiO, Mn2O3, CaSO4, BaSO4, CaFe2O5, CuFe2O4, and perovskite.

5. The apparatus for producing methanol from carbon dioxide via chemical looping combustion according to claim 3, characterized in that, The fixed-bed reactor (5B) is filled with a methanol synthesis catalyst, which is selected from one or more of Cu and Pd.

6. A method for preparing methanol using an apparatus for the hydrogenation of carbon dioxide combined with chemical looping combustion, as described in any one of claims 1-5, characterized in that, Includes the following steps: (1) Power is supplied to the electrolytic cell through a power generation system. The electrolytic cell electrolyzes water to produce hydrogen and oxygen. (2) Introduce biomass, oxygen carrier and oxygen generated by electrolysis of water with a volume fraction of 80-90% into the bottom of the chemical looping combustion reactor; (3) The gas produced after the reaction in step (2) is introduced into the pure oxygen combustion chamber along with the oxygen produced by electrolysis of water with a volume fraction of 10~20% and further reacted under the action of the catalyst to completely convert the biomass into carbon dioxide gas. (4) The carbon dioxide and hydrogen obtained by electrolysis of water are used to form a raw material gas, and the raw material gas is passed into the methanol reaction unit to obtain methanol.

7. A method for preparing methanol using an apparatus for the hydrogenation of carbon dioxide combined with chemical looping combustion, as described in claim 6, characterized in that... Step (2) specifically involves feeding biomass into a fuel reactor containing an oxygen carrier for reaction. The gas produced by the reaction is separated into gas and solid phases by a second cyclone separator. The separated gas phase is fed into a pure oxygen combustion chamber for further reaction. The separated solid phase is returned to the fuel reactor through a second flow sealing valve. The oxygen carrier at the bottom of the fuel reactor enters the bottom of the air reactor through a first flow sealing valve. After fully reacting with the air fed into the air reactor, it enters the first cyclone separator for gas-solid separation. The separated solid is the oxidized oxygen carrier, which falls into the fuel reactor to achieve circulation.

8. A method for preparing methanol using an apparatus for the hydrogenation of carbon dioxide combined with chemical looping combustion, as described in claim 7, characterized in that, Step (4) specifically involves introducing the raw material gas into the first heat exchanger. The exhaust gas from the air reactor generated in the air reactor exchanges heat with the raw material gas in the first heat exchanger to raise the temperature of the raw material gas and maintain the temperature of the raw material gas at 200~300℃. The heated raw material gas is then sequentially introduced into the fixed bed reactor, the first flash reactor, the second flash reactor, the fractionator, and the third flash reactor for full reaction. The third flash reactor flashes to produce the liquid product methanol. The gaseous products produced by the reactions in the first flash reactor, the second flash reactor, and the third flash reactor are returned to the raw material gas for further full reaction.

9. A method for preparing methanol using an apparatus for carbon dioxide hydrogenation combined with chemical looping combustion according to claim 8, characterized in that, The carbon dioxide gas generated in step (3) is condensed by a condenser, and the resulting condensate is fed into the electrolytic cell.

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