Photo-thermal-green electricity synergistic heat supply system and method for carbonate hydrogenation reduction
Through the photothermal-green and electric collaborative heating system, combined with concentrated solar energy and green electric heating, it provides a stable heat source for carbonate hydrogenation and reduction reaction, solves the problem of unstable heating supply of carbonate decomposition reaction, achieves low-carbon production and efficient heating, reduces carbon emissions and produces important chemical raw materials in conjunction with each other.
Patent Information
- Application Number
- CN202510562806.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-30
- Publication Date
- 2025-08-01
AI Technical Summary
The heating supply of carbonate decomposition reactions in the existing carbonate industry is unstable, the combustion of fossil fuels leads to high carbon emissions, and the rapid and uncontrollable hydrogen combustion leads to the risk of coking in the furnace, making it difficult to achieve stable heating and low-carbon production of carbonate hydrogenation reduction.
The photothermal-green and electric collaborative heating system is adopted, combined with the concentrated solar energy heat collector and the green electric heating device, to provide a stable heat source for carbonate hydrogenation and reduction reaction, convert solar energy into high-energy flow through transparent windows for heating, and when the solar energy is insufficient, the green electric heating device assists in heating, combined with the preheating device to preheat hydrogen and carbonate raw materials, and use high-temperature CO or synthesis gas countercurrent heat exchange to achieve continuity and reliability of heating.
It has achieved stable heating in the carbonate hydroreduction process, reduced fossil energy consumption, reduced carbon emissions, improved carbonate decomposition rate, and co-generated important chemical raw materials CO or synthesis gas to ensure the safety, reliability and control of the heating system.
Smart Images
Figure CN120393886A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the fields of solar energy utilization, carbonate hydrogenation reduction, and carbonate industrial technology, and in particular to a photothermal-green electricity coordinated heating system and method for carbonate hydrogenation reduction. Background Art
[0002] Carbonate industries, such as cement, lime, metallurgy, and calcium carbide, are typically high-energy-consuming and high-carbon-emitting. Currently, the carbonate industry's energy consumption is still primarily fossil fuel-based. The combustion of large amounts of fossil fuels and the decomposition of carbonates result in high carbon emissions during the production process, increasing the pressure on the cement industry to reduce carbon emissions. Developing new near-zero / net-zero carbon carbonate processing technologies is one of the effective ways for these carbonate industries to achieve energy conservation, consumption reduction, low-carbon production, and green development.
[0003] Carbonate hydrogenation reduction technology uses the principle of direct reduction of carbonates with hydrogen. Without changing the solid-phase products, the gaseous product CO2 is regulated to CO, thereby achieving a significant reduction in carbon emissions from industrial processes. Theoretical studies have shown that compared with the carbonate decomposition reaction, the carbonate hydrogenation reduction reaction has a higher overall heat absorption capacity. How to provide continuous and stable heat for this reaction has become a bottleneck problem that this technology urgently needs to break through. Currently, in terms of alternative heating technologies, they mainly include solar energy and hydrogen energy: when solar energy is used as the only heating method, its intermittent and unstable nature cannot guarantee the continuity and reliability of heating; when hydrogen energy is used as the heating method, the rapidity and uncontrollability of hydrogen combustion and the local high temperature generated by combustion will lead to unstable heating for carbonate decomposition and the risk of coking in the furnace. Summary of the Invention
[0004] Purpose of the invention: In view of the above shortcomings, the present invention provides a photothermal-green electricity coordinated heating system and method for carbonate hydrogenation reduction to reduce carbon emissions from the carbonate industry.
[0005] Technical solution: In order to solve the above problems, the present invention adopts a photothermal-green electricity coordinated heating system for carbonate hydrogenation reduction, including a reactor body device for hydrogen reduction of carbonate raw materials, a gas-solid separation device for separating reaction products, a concentrating solar thermal collection device, a green electricity heating device and a preheating device. The reactor body device is provided with a transparent window. The concentrating solar thermal collection device converts sunlight into high-energy flow and enters the reactor body device through the transparent window to provide heat for the reactor body device. The green electricity heating device is used to assist in providing heat for the reactor body device when the concentrating solar thermal collection device does not provide sufficient heat. The preheating device is used to preheat the hydrogen and carbonate raw materials entering the reactor body device. The gaseous products separated by the gas-solid separation device are passed into the preheating device to preheat the hydrogen and carbonate raw materials.
[0006] Furthermore, the reactor body device is provided with a transparent window, a green electricity heating device, a preheated hydrogen / carbonate raw material inlet, and a reduction product outlet; the preheating device is provided with a non-contact gas-solid heat exchanger, a hydrogen / carbonate raw material inlet, a CO or syngas inlet, a preheated hydrogen / cement carbonate raw material outlet, and a CO or syngas outlet; the gas-solid separation device is provided with a cyclone separator, a reduction product inlet, a gas-phase product outlet, and a solid-phase product outlet; the preheated hydrogen / carbonate raw material outlet of the preheating device is connected to the preheated hydrogen / carbonate raw material inlet of the reactor body device; the reduction product outlet of the reactor body device is connected to the reduction product inlet of the gas-solid separation device; the gas-phase product outlet of the gas-solid separation device is connected to the CO or syngas inlet of the preheating device. The hydrogen / carbonate raw material inlet is arranged at the upper front part of the preheating device; the preheated hydrogen / carbonate raw material outlet is arranged at the lower rear part of the preheating device; the preheated hydrogen / carbonate raw material inlet is arranged at the bottom of the reactor body device; the reduction product outlet is arranged at the upper right side of the reactor body device; the reduction product inlet is arranged at the upper left side of the gas-solid separation device; the solid-phase product outlet is arranged at the bottom of the gas-solid separation device; the gas-phase product outlet is arranged at the top of the gas-solid separation device; the CO or syngas inlet is arranged at the upper rear part of the preheating device; the CO or syngas outlet is arranged at the lower front part of the preheating device.
[0007] Furthermore, the concentrating solar thermal collector device is provided with a heliostat field that surrounds the reactor body device 360°; the heliostat field has a function and control system for tracking sunlight; the high-temperature transparent window can be one of quartz glass, borosilicate glass, magnesium oxide transparent ceramic, and magnesium aluminate spinel transparent ceramic.
[0008] Furthermore, the heating method of the green electricity heating device can be one or two of external Joule heating, electromagnetic heating, microwave heating, and plasma heating; the electric energy of the green electricity heating device comes from one or more of solar photovoltaic power generation, wind power generation, and other renewable energy power generations including but not limited to these.
[0009] Furthermore, the heating method of the reactor body device is the coupling of concentrating solar heating and green electricity heating, and its flow form can be a fluidized bed, a gas-solid two-phase flow bed, or a spouted bed. The gas-solid separation device is a high-temperature cyclone separator. The preheating device is a non-contact countercurrent tubular gas-solid heat exchanger, and its heating method is that high-temperature CO or syngas is used as a heat source to exchange heat in a countercurrent flow manner through the tubular heat exchanger.
[0010] The present invention also adopts a heating method based on the above-mentioned solar-thermal / green-electricity collaborative heating system for hydrogenation reduction of carbonate, including the following steps:
[0011] Hydrogen enters the reactor main body device through the preheating device. The concentrating solar thermal collector device and the green electricity heating device quickly heat the hydrogen to above 650°C. The high-temperature hydrogen discharged from the reduction product outlet at the top of the reactor main body device enters the preheating device successively through the gas-phase product outlet of the gas-solid separation device and the CO or syngas inlet of the preheating device. Hydrogen, as a transport medium and carbonate raw material, enters the preheating device from the hydrogen / carbonate raw material inlet of the preheating device and is preheated to 500°C - 600°C by the high-temperature hydrogen. Then it enters the reactor main body device successively through the preheated hydrogen / carbonate raw material outlet of the preheating device and the preheated hydrogen / carbonate raw material inlet of the reactor main body device. The preheated hydrogen and carbonate raw material are heated to about 650°C by the concentrating solar thermal collector device and the green electricity heating device and undergo a reduction reaction to obtain metal oxides, CO, and H2O, with the raw material decomposition rate reaching over 95%. The reduction products (including the solid-phase product - metal oxides and the gas-phase product - CO or syngas) are discharged from the reduction product outlet of the reactor main body device and enter the gas-solid separation device through the reduction product inlet of the gas-solid separation device. The gas-phase product (CO or syngas) and the solid-phase product (metal oxides) in the reduction products are separated by the gas-solid separation device. The metal oxides are discharged from the solid-phase product outlet of the gas-solid separation device and can be used as intermediate products for subsequent production or directly as final products. The high-temperature CO or syngas is discharged from the gas-phase product outlet of the gas-solid separation device and enters the preheating device through the CO or syngas inlet of the preheating device. The high-temperature CO or syngas preheats the hydrogen and carbonate raw material in a countercurrent manner in the preheating device and preheats them to 500°C - 600°C. The preheated hydrogen and carbonate raw material are discharged from the preheated hydrogen / carbonate raw material outlet of the preheating device. Finally, the CO or syngas is discharged from the CO or syngas outlet of the preheating device after waste heat utilization and can be further processed and utilized as an important chemical raw material.
[0012] The concentrating solar thermal collector device converts solar energy into high-throughput heat and enters the reactor main body device through the transparent window. The green electricity heating device provides auxiliary heating for the reactor main body device. The reactor main body device is a new type of thermal equipment that simultaneously conducts heat exchange, decomposition reaction, and reduction reaction during the carbonate decomposition process. The gas-solid separation device is used to separate the solid-phase product (metal oxides) and the gas-phase product (CO or syngas) discharged from the reactor main body device. The preheating device is used to preheat the hydrogen and carbonate raw material entering the reactor main body device.
[0013] When the solar radiation is sufficient, the concentrating solar thermal collector device is used to convert solar energy into heat energy to supply heat to the reactor main body device. When the solar radiation is insufficient, the green electricity heating device is used as an auxiliary heat source to supplement the heat supply for the reactor main body device to ensure the temperature requirement and stable operation of the reaction.
[0014] Furthermore, the carbonate hydrogenation reduction process can be used in industries including but not limited to cement, lime, metallurgy, and calcium carbide production. Hydrogen can come from, including but not limited to, electrolytic hydrogen production from renewable energy such as wind / solar, hydrogen production from biomass gasification, hydrogen production from coal / oil / natural gas, by-product hydrogen production, and nuclear hydrogen production.
[0015] The present invention also adopts a photo-electric combined heating experimental device for carbonate hydrogenation reaction based on the above heating method, which includes a storage tank for introducing reaction raw materials, a riser pipe arranged in the storage tank, an annulus pipe for carrying out the reaction of hydrogen reducing carbonate raw materials, a receiving chamber arranged at the outlet of the annulus pipe, an electric heating device, and a solar simulator. The annulus pipe includes an inner pipe and an outer pipe sleeved outside the inner pipe. The inner pipe is communicated with the riser pipe. One end of the outer pipe is connected to the storage tank, and the other end is connected to the receiving chamber. A carbonate raw material inlet is arranged at the upper end of the storage tank, and a hydrogen inlet is arranged at the bottom. The hydrogen inlet is communicated with the riser pipe, and a return hole is arranged on the side surface of the bottom of the riser pipe, which is communicated with the storage tank. The electric heating device is arranged outside the annulus pipe and is used for assisting in heating or preheating the reaction of hydrogen reducing carbonate raw materials in the annulus pipe. A transparent window is arranged at the top of the receiving chamber, and the solar simulator heats the hydrogen and carbonate raw materials ejected into the inner pipe of the annulus pipe through the transparent window. The receiving chamber is provided with a gas-phase reduction product outlet for discharging the gas-phase reduction product of hydrogen reducing carbonate raw materials. The solid-phase reduction product of hydrogen reducing carbonate raw materials and the unreacted carbonate raw materials enter the storage tank through the outer pipe of the annulus pipe.
[0016] Beneficial effects: Compared with the prior art, the significant advantages of the present invention are:
[0017] (1) Using solar energy and green electricity collaborative heating to replace the combustion of traditional fossil fuels in the carbonate industry to provide heat for carbonate decomposition and recycling the waste heat after the reaction can not only greatly reduce the consumption of fossil energy but also achieve net-zero emissions of CO2 from fuel combustion, contributing to the low-carbon and green development of industries such as cement, lime, and metallurgy.
[0018] (2) The organic combination of solar energy and green electricity heating technologies not only realizes the effective utilization of renewable energy but also ensures the stable heating of carbonate hydrogenation reduction. Compared with the current new carbonate decomposition technologies, the present invention effectively avoids and solves problems such as the intermittency and instability of solar energy, the rapidity and uncontrollability of hydrogen combustion, and the unstable heat supply and furnace coking caused by the local high temperature generated by hydrogen combustion, and has the advantages of safety, reliability, and easy control.
[0019] (3) The carbonate hydrogenation reduction technology is coupled to the carbonate decomposition process. By regulating the gaseous product CO2 into CO, nearly zero / net zero emissions of CO2 are achieved during the carbonate decomposition process, and important chemical raw materials CO or syngas are co-produced. At the same time, the decomposition temperature of carbonate in a hydrogen atmosphere is significantly reduced, and the carbonate decomposition rate is as high as over 95%.
[0020] (4) The photothermal-green electricity co-heating system and method for carbonate hydrogenation reduction of the present invention provide an innovative, green, and low-carbon heating method for the carbonate industry. The scale can be flexibly designed and arranged according to actual situations, and it has good market and promotion application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 It is a schematic diagram of the photothermal-green electricity co-heating system for carbonate hydrogenation reduction in the present invention;
[0022] Figure 2 It is a carbonate hydrogenation reaction device for combined photo-electric heating on a laboratory scale in the present invention;
[0023] Figure 3 It is a reaction curve of limestone under different temperature conditions in a hydrogen atmosphere in the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0024] Example 1:
[0025] As Figure 1As shown in the figure, in this embodiment, a solar thermal - green electricity collaborative heating system for hydrogenation reduction of carbonate includes a concentrating solar collector 5, a green electricity heating device 4, a reactor body device 2, a gas - solid separation device 3, a preheating device 1, a hydrogen / carbonate raw material inlet 101, a preheated hydrogen / carbonate raw material outlet 102, a CO or syngas inlet 103, a CO or syngas outlet 104, a preheated hydrogen / carbonate raw material inlet 201, a reduction product outlet 202, a reduction product inlet 301, a gas - phase product outlet 302, a solid - phase product outlet 303, a heliostat field 501 and a transparent window 502. The reactor body device 2 is provided with a transparent window 502, a green electricity heating device 4, a preheated hydrogen / carbonate raw material inlet 201 and a reduction product outlet 202; the gas - solid separation device 3 is provided with a cyclone separator, a reduction product inlet 301, a gas - phase product outlet 302 and a solid - phase product outlet 303; the preheating device 1 is provided with a non - contact gas - solid heat exchanger, a hydrogen / carbonate raw material inlet 101, a CO or syngas inlet 103, a preheated hydrogen / carbonate raw material outlet 102 and a CO or syngas outlet 104; the preheated hydrogen / carbonate raw material outlet 102 of the preheating device 1 is connected to the preheated hydrogen / carbonate raw material inlet 201 of the reactor body device 2; the reduction product outlet 202 of the reactor body device 2 is connected to the reduction product inlet 301 of the gas - solid separation device 3; the gas - phase product outlet 302 of the gas - solid separation device is connected to the CO or syngas inlet 103 of the preheating device 1.
[0026] The hydrogen / carbonate raw material inlet 101 is arranged at the upper front part of the preheating device 1; the preheated hydrogen / carbonate raw material outlet 102 is arranged at the lower rear part of the preheating device 1; the green electricity heating device 4 is arranged below the reactor body device 2; the transparent window 502 is arranged above the reactor body device 2; the preheated hydrogen / carbonate raw material inlet 201 is arranged at the bottom of the reactor body device 2; the reduction product outlet 202 is arranged at the upper right side of the reactor body device 2; the reduction product inlet 301 is arranged at the upper left side of the gas - solid separation device 3; the solid - phase product outlet 303 is arranged at the bottom of the gas - solid separation device 3; the gas - phase product outlet 302 is arranged at the top of the gas - solid separation device 3; the CO or syngas inlet 103 is arranged at the upper rear part of the preheating device 1; the CO or syngas outlet 104 is arranged at the lower front part of the preheating device 1.
[0027] The concentrating solar heat collection device 5 includes a heliostat field 501 with the function of tracking sunlight and an automatic control system that surrounds the reactor body device 360°, and a high-temperature resistant transparent window 502 made of quartz glass, borosilicate glass, magnesia transparent ceramic or magnesium aluminate spinel transparent ceramic. The heating method of the green electricity heating device 4 can be one or two of external Joule heating, electromagnetic heating, microwave heating and plasma heating; the electric energy of the green electricity heating device 4 comes from one or more of solar photovoltaic power generation, wind power generation and other renewable energy power generation including but not limited to these. The heat supply source of the reactor body device 2 is the combined heat supply of the concentrating solar heat collection device 5 and the green electricity heating device 4, and its flow form can be fluidized bed, entrained flow bed and spouted bed; the reducing atmosphere in the reactor body device 2 is hydrogen, which can come from electrolytic hydrogen production from renewable energy such as wind / solar, biomass gasification hydrogen production, coal / oil / natural gas hydrogen production, by-product hydrogen production, nuclear hydrogen production; the preheated hydrogen and carbonate raw materials move in an overall upward flow manner in the reactor body device 2. The gas-solid separation device 3 is a high-temperature cyclone separator. The preheating device 1 is a non-contact tubular gas-solid heat exchanger, and its heat supply method is that high-temperature CO or syngas exchanges heat in a countercurrent flow manner through the tubular heat exchanger.
[0028] In this embodiment, the concentrating solar heat collection device 5 converts solar energy into high-flux heat and enters the reactor body device 2 through the transparent window. The green electricity heating device 4 provides auxiliary heat for the reactor body device 2. The reactor body device 2 is a new type of thermal equipment for hydrogenation reduction of carbonate that can carry out heat exchange, decomposition reaction and reduction reaction simultaneously; the reactor body device 2 has the characteristics of a wide range of heating methods, good heat transfer effect, low heat loss, easy control and flexible adjustment, and can quickly transfer the high-flux solar energy from the concentrating solar heat collection device 5 and the heat of the green electricity heating device 4 to the carbonate raw materials and hydrogen to quickly reach and maintain the temperature and heat required for the hydrogenation reduction reaction of carbonate. The solar thermal and electric heating are synchronous or dynamically alternating, and cooperate in real time; in terms of positional relationship, a solar thermal concentrator is integrated at the top of the reactor, and at the same time, electric heating elements are arranged along the entire length of the reactor to achieve local optimal heating; in terms of reactor matching, the entire heating system has good geometric coordination with the fluidized bed structure, eliminating pipelines and dead corners, improving the heat transfer efficiency, designing the solar thermal collection unit as a concentric ring with the outer wall of the fluidized bed cylinder, and at the same time distributing non-contact inductive heating elements along the axial and circumferential directions of the cylinder to ensure uniform distribution of radiant heat.
[0029] The gas-solid separation device is used to separate the solid-phase product (metal oxide) and the gas-phase product (CO or syngas) discharged from the reactor body device; the preheating device is used to preheat the hydrogen and carbonate raw materials entering the reactor body device.
[0030] The heating method of the above-mentioned solar-thermal and green-electricity collaborative heating system for hydrogenation reduction of carbonate includes the following steps: Hydrogen enters the reactor body device 2 through the preheating device 1, and the hydrogen is rapidly heated to above 650 °C by the concentrating solar collector device 5 and the green-electricity heating device 4; The high-temperature hydrogen discharged from the reduction product outlet 201 at the top of the reactor body device 2 enters the preheating device through the gas-phase product outlet 302 of the gas-solid separation device 3 and the CO or syngas inlet 103 of the preheating device in sequence; Hydrogen, as a transport medium and carbonate raw material, enters the preheating device from the hydrogen / carbonate raw material inlet 101 of the preheating device and is preheated to 500 °C to 650 °C by the high-temperature hydrogen, and then enters the reactor body device 2 through the preheated hydrogen / carbonate raw material outlet 102 of the preheating device and the preheated hydrogen / carbonate raw material inlet 201 of the reactor body device; Hydrogen and carbonate raw material are heated to above 650 °C in the reactor body device 2 by the concentrating solar collector device 5 and the green-electricity heating device 4 and undergo a reduction reaction to obtain metal oxide, CO, and H2O, and the raw material decomposition rate reaches over 95%; The reduction products (including solid-phase products - metal oxides and gas-phase products - CO or syngas) are discharged from the reduction product outlet 202 of the reactor body device 2 and enter the gas-solid separation device through the reduction product inlet 301 of the gas-solid separation device 3; The separated metal oxide is discharged from the solid-phase product outlet 303 of the gas-solid separation device 3 and can be used as an intermediate product for subsequent production or directly as the final product; The separated high-temperature CO or syngas is discharged from the gas-phase product outlet 302 of the gas-solid separation device 3; The high-temperature CO or syngas enters the preheating device from the CO or syngas inlet 103 of the preheating device and preheats the hydrogen and carbonate raw material entering from the hydrogen / carbonate raw material inlet 101 of the preheating device in a countercurrent manner and preheats them to 500 °C to 600 °C, and the preheated hydrogen and carbonate raw material are discharged from the preheated hydrogen / carbonate raw material outlet 102 of the preheating device 1; Finally, the CO or syngas is discharged from the CO or syngas outlet 104 of the preheating device after waste heat utilization and can be further processed and utilized as an important chemical raw material.
[0031] In this embodiment, when the solar radiation is sufficient, the concentrating solar collector device is used to convert solar energy into heat energy to heat the reactor body device; when the solar radiation is insufficient, the green-electricity heating device is used as an auxiliary heat source to supplement the heating of the reactor body device to ensure the temperature requirement and stable operation of the reaction.
[0032] Example 2:
[0033] Based on a photothermal - green electricity co - heating method for hydrogenation reduction of carbonate according to the present invention, the present invention provides a laboratory - scale photo - electric combined heating device for hydrogenation reaction of carbonate, including a solar simulator - xenon lamp 601, a transparent window 602, a receiving chamber 603, a riser 604, an annulus pipe 605, an electric heating device 606, an annular baffle 607, a storage tank 608, a return hole 609, a distributor plate 610, a hydrogen inlet 611, a carbonate raw material inlet 612 and a gas - phase reduction product outlet 613. The solar simulator - xenon lamp is arranged at the top of the reaction device to provide the heat required for the reaction, and the temperature can reach 600°C - 900°C; an optical coating for increasing the blackness is provided in the receiving chamber; the gas - phase product outlet is arranged above the receiving chamber (uniformly distributed around the receiving chamber, 2); the annulus pipe is connected to the receiving chamber and the storage tank up and down; the electric heating device is arranged outside the annulus pipe to heat hydrogen and carbonate raw materials, and the temperature can reach 600°C - 900°C; the annular baffle (with an inclination angle of 45° / 135°) is connected to the riser; the return hole is arranged at the position where the riser contacts the storage tank (uniformly distributed around the riser, 3); the distributor plate is arranged at the lower end of the riser; the carbonate raw material inlet is arranged above the storage tank (uniformly distributed around the storage tank, 2); the hydrogen inlet is arranged at the bottom of the riser. The specific process is as follows: Hydrogen and carbonate enter the riser together through the hydrogen inlet and the carbonate raw material inlet in the storage tank. Hydrogen, as the transport medium and the carbonate raw material, flow upward as a whole in the riser and first undergo a partial reduction reaction after being pre - heated / heated by the electric heating device; Subsequently, the carbonate raw material is heated again by the xenon lamp in the form of a "fountain" above the riser to undergo a reduction reaction. The gas - phase reduction product is discharged through the gas - phase reduction product outlet, and the solid - phase reduction product and the incompletely reacted carbonate raw material enter the storage tank through the annulus pipe and the annular baffle; Subsequently, the two enter the riser together with hydrogen through the return hole, and the above process is repeated until no CO is produced in the gas - phase reduction product.
[0034] Example 3:
[0035] Based on the carbonate hydrogenation reaction device for combined photo - electric heating at laboratory scale in Example 2, this example provides an experimental process in the reaction device, which specifically includes the following steps: Accurately weigh 180 g of limestone with a particle size of 0.2 mm - 0.3 mm and place it in the fluidized bed reactor. The fluidized bed reactor is heated from room temperature to 600 °C, 650 °C, 700 °C, 750 °C, 800 °C, 850 °C, 900 °C at a heating rate of 10 °C / min. During the heating process, 1 L / min of CO2 gas is used as the protective gas to prevent the decomposition of limestone during this process; when the reactor temperature reaches 600 °C, 650 °C, 700 °C, 750 °C, 800 °C, 850 °C, 900 °C respectively, quickly switch the CO2 gas to 4 L / min of H2, and at the same time, the flue gas analyzer starts to record the reaction characteristics of limestone in the hydrogen atmosphere until the reaction ends.
[0036] As Figure 3 Figure is the reaction characteristics of limestone with hydrogen under different temperature conditions in the fluidized bed reactor. The results show that when the temperature is higher than 650 °C, limestone can react with hydrogen to undergo a reduction reaction, and the main gas product is CO; 650 °C is exactly at the optimal intersection point of the thermodynamic decomposition of limestone and the reduction kinetics of hydrogen, enabling both the conversion rate of limestone and the selectivity of CO to maintain a relatively high level; in the experiment, the fluidized bed structure ensures sufficient gas - solid contact, uniform temperature distribution, and particle suspension state, further ensuring a high conversion rate (>95%) and a high CO selectivity (~93%), providing a feasibility basis for the application of this process on an industrial scale.
[0037] In summary, a solar thermal - green electricity collaborative heating system and method for carbonate hydrogenation reduction provided by the present invention, under the background of the rapid development of renewable energy utilization, green electricity, and hydrogen production technologies, as well as energy conservation, carbon reduction, and green production in the carbonate industry, applies the concentrated solar thermal collection technology, green electricity heating technology, and carbonate hydrogenation reduction technology to the carbonate decomposition process, providing new ideas for the green and low - carbon transformation of carbonate industries such as cement, lime, and metallurgy.
Claims
1. A photothermal-green electricity co-heating system for hydrogenation reduction of carbonate, characterized in that It includes a reactor body device (2) for carrying out the reaction of hydrogen reduction of carbonate raw materials, a gas-solid separation device (3) for separating reaction products, a concentrating solar heat collection device (5), a green electricity heating device (4) and a preheating device (1). The reactor body device (2) is provided with a transparent window (502). The concentrating solar heat collection device (5) converts sunlight into high-energy flow and enters the reactor body device (2) through the transparent window (502) to supply heat to the reactor body device (2). The green electricity heating device (4) is used to assist in heating the reactor body device (2) when the heat supply of the concentrating solar heat collection device (5) is insufficient. The preheating device (1) is used to preheat the hydrogen and carbonate raw materials entering the reactor body device (2). The gas-phase product separated by the gas-solid separation device (3) is introduced into the preheating device (1) to preheat the hydrogen and carbonate raw materials.
2. The photothermal-green electricity collaborative heating system for hydrogenation reduction of carbonate according to claim 1, characterized in that The reactor body device (2) includes a preheated hydrogen / carbonate raw material inlet (201) and a reduction product outlet (202). The gas-solid separation device (3) includes a reduction product inlet (301), a gas-phase product outlet (302) and a solid-phase product outlet (303). The preheating device (1) includes a hydrogen / carbonate raw material inlet (101), a CO or synthesis gas inlet (103), a preheated hydrogen / carbonate raw material outlet (102) and a CO or synthesis gas outlet (104). The preheated hydrogen / carbonate raw material outlet (102) of the preheating device (1) is connected to the preheated hydrogen / carbonate raw material inlet (201) of the reactor body device (2). The reduction product outlet (202) of the reactor body device (2) is connected to the reduction product inlet (301) of the gas-solid separation device (3). The gas-phase product outlet (302) of the gas-solid separation device is connected to the CO or synthesis gas inlet (103) of the preheating device (1).
3. The photothermal-green electricity collaborative heating system for hydrogenation reduction of carbonate according to claim 2, wherein The hydrogen / carbonate raw material inlet (101) is arranged at the upper front part of the preheating device (1); the preheated hydrogen / carbonate raw material outlet (102) is arranged at the lower rear part of the preheating device (1); the CO or syngas inlet (103) is arranged at the upper rear part of the preheating device (1); the CO or syngas outlet (104) is arranged at the lower front part of the preheating device (1). The hydrogen / carbonate raw material inlet (101) is communicated with the preheated hydrogen / carbonate raw material outlet (102) through a raw material transportation pipeline. The CO or syngas inlet (103) is communicated with the CO or syngas outlet (104) through a preheating pipeline, and the preheating pipeline wraps the raw material transportation pipeline for connection. The transparent window (502) is arranged at the top of the reactor body device (2); the green electricity heating device (4) is arranged below the reactor body device (2); the preheated hydrogen / carbonate raw material inlet (201) is arranged at the bottom of the reactor body device (2); the reduced product outlet (202) is arranged at the upper right side of the reactor body device (2); the reduced product inlet (301) is arranged at the upper left side of the top of the gas-solid separation device (3); the solid-phase product outlet (303) is arranged at the bottom of the gas-solid separation device (3); the gas-phase product outlet (302) is arranged at the top of the gas-solid separation device (3).
4. The photothermal-green electricity collaborative heating system for hydrogenation reduction of carbonate according to claim 3, wherein The concentrating solar heat collection device (5) includes a heliostat field (501). The heliostat field (501) surrounds the reactor body device (2) 360°. Through the function and control system of tracking sunlight, it reflects sunlight into the reactor body device (2) from the transparent window (502) to supply heat to the reactor body device (2). The transparent window (502) is a high-temperature resistant transparent window, and the materials used include quartz glass, borosilicate glass, magnesium oxide transparent ceramic, and magnesium aluminate spinel transparent ceramic.
5. The photo-thermal and green electricity co-supplied heating system for hydrogenation reduction of carbonate according to claim 1, wherein The heating methods of the green electricity heating device (4) include one or two of external Joule heating, electromagnetic heating, microwave heating, and plasma heating; the electrical energy sources of the green electricity heating device (4) include one or more of solar photovoltaic power generation, wind power generation, and other renewable energy power generations.
6. The photo-thermal and green electricity co-heating system for hydrogenation reduction of carbonate according to claim 1, characterized in that The form of the reactor body device (2) includes a fluidized bed, a gas entrained bed, and a spouted bed; the applicable fields of the carbonate hydrogenation reduction process include the cement, lime, metallurgy, and calcium carbide production industries; the gas-solid separation device (3) is a high-temperature cyclone separator.
7. The photo-thermal and green electricity co-heating system for hydrogenation reduction of carbonate according to claim 1, wherein The preheating device (1) is a non-contact gas-solid heat exchanger, and its preheating atmosphere is the high-temperature CO or syngas discharged from the reactor body device (2) through the gas-solid separation device (3), with a temperature reaching 600°C to 900°C; the non-contact gas-solid heat exchanger is a countercurrent tubular gas-solid heat exchanger.
8. The photo-thermal and green electricity collaborative heating system for hydrogenation reduction of carbonate according to claim 7, wherein, The sources of the hydrogen include hydrogen production by electrolyzing water using renewable energy, hydrogen production by biomass gasification, hydrogen production from coal / oil / natural gas, hydrogen production from by-products, and hydrogen production by nuclear energy.
9. A heating method for a photothermal-green electricity collaborative heating system for hydrogenation reduction of carbonate according to claim 1, characterized in that It includes the following steps: Hydrogen enters the reactor body device (2) through the preheating device (1), and the concentrated solar heat collection device (5) and the green electricity heating device (4) quickly heat the hydrogen to above 650°C; the high-temperature hydrogen discharged from the reduction product outlet (201) at the top of the reactor body device (2) enters the preheating device (1) successively through the gas-phase product outlet (302) of the gas-solid separation device (3) and the CO or syngas inlet (103) of the preheating device (1); hydrogen, as a transport medium and carbonate raw material, enters the preheating device (1) from the hydrogen / carbonate raw material inlet (101) of the preheating device (1), is preheated by the high-temperature hydrogen, and then enters the reactor body device (2) successively through the preheated hydrogen / carbonate raw material outlet (102) of the preheating device (1) and the preheated hydrogen / carbonate raw material inlet (201) of the reactor body device (2); hydrogen and carbonate raw materials are heated to 650°C in the reactor body device (2) by the concentrated solar heat collection device (5) and the green electricity heating device (4) and undergo a reduction reaction to obtain metal oxides, CO, and H2O, and the raw material decomposition rate reaches over 95%; the reduction product is discharged from the reduction product outlet (201) of the reactor body device (2) and enters the gas-solid separation device (3) through the reduction product inlet (301) of the gas-solid separation device (3); the metal oxides separated by the gas-solid separation device (3) are discharged from the solid-phase product outlet (303) of the gas-solid separation device (3) and are used as intermediate products for subsequent production or directly as final products; the CO or syngas separated by the gas-solid separation device (3) is first discharged from the gas-phase product outlet (302) of the gas-solid separation device (3) and enters the preheating device (1) from the CO or syngas inlet (103) of the preheating device (1) in a countercurrent flow mode to preheat hydrogen and carbonate raw materials; finally, the CO or syngas is discharged from the CO or syngas outlet (104) of the preheating device (1) after waste heat utilization and is further processed and utilized as an important chemical raw material.
10. An experimental device for the photo - electro - combined heat - supply carbonate hydrogenation reaction based on the heat - supply method described in claim 9, characterized in that, It includes a storage tank (608) for introducing reaction raw materials, a riser pipe (604) arranged in the storage tank (608), an annulus pipe (605) for carrying out the reaction of hydrogen reducing carbonate raw materials, a receiving chamber (603) arranged at the outlet of the annulus pipe (605), an electric heating device (606) and a solar simulator (601). The annulus pipe (605) includes an inner pipe and an outer pipe sleeved outside the inner pipe. The inner pipe is communicated with the riser pipe (604). One end of the outer pipe is connected to the storage tank (608), and the other end is connected to the receiving chamber (603). A carbonate raw material inlet (612) is arranged at the upper end of the storage tank (608), and a hydrogen inlet (611) is arranged at the bottom. The hydrogen inlet (611) is communicated with the riser pipe (604), and a return hole (9) is arranged on the side surface of the bottom of the riser pipe (604), and the return hole (9) is communicated with the storage tank (608). The electric heating device (606) is arranged outside the annulus pipe (605) and is used for assisting in heating or preheating the reaction of hydrogen reducing carbonate raw materials in the annulus pipe (605). A transparent window (602) is arranged at the top of the receiving chamber (603). The solar simulator (601) heats the hydrogen and carbonate raw materials ejected into the inner pipe of the annulus pipe (605) through the transparent window (602). The receiving chamber (603) is provided with a gas-phase reduction product outlet (13) for discharging the gas-phase reduction product of hydrogen reducing carbonate raw materials. The solid-phase reduction product of hydrogen reducing carbonate raw materials and the carbonate raw materials that are not completely reacted enter the storage tank through the outer pipe of the annulus pipe.