A near-zero CO2 emission hydrogen and solid carbon cogeneration device

Abstract

This invention discloses a near-zero CO2 emission hydrogen and solid carbon co-production device, relating to the fields of catalytic gas cracking hydrogen production via molten liquid media and carbon materials technology. It addresses the problems of high carbon emissions, high energy consumption, easy catalyst deactivation, and difficulty in separating carbon products in existing hydrogen production technologies. The device includes a methane cracking reactor with an internal methane cracking reaction zone and a carbon product storage transition zone between the reactor and the reaction zone. An air reactor is connected to a circulation mechanism. A novel energy supply method provides the necessary energy for methane cracking, achieving zero CO2 emissions during the energy supply process. This invention utilizes the excellent thermal conductivity, fluidity, and catalytic capacity of the molten liquid medium to effectively solve problems such as catalyst deactivation. By setting up the methane cracking reaction zone and the carbon product storage transition zone, automatic and continuous separation of solid carbon particles is achieved, ensuring the continuous, stable, and safe operation of the entire device.

Description

Technical Field

[0001] This invention relates to the field of petroleum and natural gas chemical production technology, and more specifically to the field of hydrogen production through catalytic gas cracking in molten liquid phase media and carbon materials technology. Background Technology

[0002] Reducing greenhouse gas emissions to mitigate climate change has reached a broad global consensus, culminating in the formal adoption of the Paris Agreement at the UN Climate Change Conference in December 2015. This agreement aims to urge and strengthen countries' capacity to address the challenge of climate change, limiting global temperature rise to well below 2°C and striving towards 1.5°C. Hydrogen energy has garnered widespread attention due to its clean, low-carbon, and sustainable characteristics, and its utilization is projected to contribute 20% to global CO2 emission reductions by 2050.

[0003] Currently, hydrogen production processes mainly include: hydrogen production from fossil fuels, electrolysis, chemical pyrolysis, and bioconversion. Although electrolysis offers advantages such as simple operation and high hydrogen purity, its high power consumption is the primary obstacle to its industrial application. On the other hand, due to limitations in cost, efficiency, and resource distribution, renewable energy hydrogen production technologies will remain dominant in the fossil fuel sector for a considerable period, while traditional hydrogen production processes face problems such as high energy consumption and high carbon emissions. Therefore, finding a hydrogen production process that balances high efficiency and low carbon emissions is crucial for accelerating the large-scale utilization of hydrogen energy and improving the development of the upstream and downstream industrial chains.

[0004] Methane thermal cracking method (cracking reaction: Methane thermal cracking is considered a potential, low-cost production method because, theoretically, its energy consumption for hydrogen production is lower than that of traditional methane steam reforming and water electrolysis. Furthermore, due to the lack of oxygen, the carbon products exist only in solid carbon form, directly preventing CO2 emissions and offering significant environmental benefits. However, methane thermal cracking also has its own drawbacks. For example, the generated solid carbon powder can coat the active surface of the catalyst and adhere to the reactor walls, causing catalyst deactivation and reactor pipe blockage, thus affecting the normal progress of the cracking reaction and limiting its industrial scale-up. Moreover, although the cracking reaction does not directly produce CO2 emissions, maintaining the reaction requires a large amount of heat energy, indirectly leading to greenhouse gas emissions and significantly reducing the emission reduction effect. In addition, the automatic and continuous separation of carbon products also presents problems, requiring the reaction to be stopped to collect the generated carbon products. Frequent start-ups and shutdowns of the equipment directly affect its lifespan and the continuous and stable output of the product. Summary of the Invention

[0005] The purpose of this invention is to address the problems of high carbon emissions, high energy consumption, easy catalyst deactivation, and difficulty in separating carbon products in existing hydrogen production technologies. This invention provides a near-zero CO2 emission hydrogen and solid carbon co-production device.

[0006] To achieve the above objectives, the present invention specifically adopts the following technical solution: a near-zero CO2 emission hydrogen and solid carbon co-production device, comprising a methane cracking reactor, wherein a methane cracking reaction zone is provided inside the methane cracking reactor, and a carbon product storage transition zone is provided between the methane cracking reactor and the methane cracking reaction zone, wherein the top of the methane cracking reaction zone is located in the upper middle part of the methane cracking reactor, an air reactor is provided in the middle of the methane cracking reaction zone, the top of the air reactor is level with the top of the methane cracking reactor, a gas supply pipe extending to the outside of the methane cracking reactor is provided in the methane cracking reaction zone, a filter and a gas separator are sequentially connected to the top of the methane cracking reactor, and a circulation function mechanism is connected to the air reactor.

[0007] In this application's technical solution, an air reactor is embedded within the methane cracking reaction zone, primarily providing energy for the methane cracking reaction process. The methane cracking reactor contains the methane cracking reaction zone, and a carbon product storage and transition zone is provided between the methane cracking reactor and the methane cracking reaction zone. The top of the methane cracking reaction zone is located in the upper middle part of the methane cracking reactor. The feed gas (methane and / or C20) is... x H yThe gas enters the bottom of the methane cracking reaction zone through a gas supply pipe. The reaction zone contains a certain amount of molten liquid medium. The generated solid carbon particles (which can be graphene, carbon nanotubes, carbon black, carbon spheres, etc., depending on the liquid catalytic medium used and the reaction temperature) have a significant density difference with the molten liquid medium, causing them to float on the surface. When the solid carbon particles generated in the methane cracking reaction zone accumulate to a certain height, they automatically overflow from the reaction zone and flow into the carbon product storage transition zone. Carbon extraction holes are provided on the outer periphery of the bottom of the methane cracking reactor. Under the action of a vacuum pump, the solid carbon particles are extracted from the carbon extraction holes. The gas is extracted through a filter from the methane cracking reactor. The filter separates carbon particles entrained in the gas components, and the separated solid carbon particles are recovered. The gas components then continue into a gas separator to obtain high-purity hydrogen. The separated unreacted gas can be recycled back to the methane cracking reactor as feedstock or back to the fuel reactor as fuel. The entire cracking process achieves automatic and continuous separation of carbon products. By combining it with a novel energy supply method, the entire cracking reaction and energy supply process achieves near-zero CO2 emissions. Furthermore, the co-production of hydrogen and solid carbon products significantly improves the system's energy utilization efficiency compared to traditional single-product hydrogen and carbon production processes. This reduces carbon emissions per unit of output energy and also reduces indirect greenhouse gas emissions from fuel consumption. Moreover, the produced carbon products can be sold for profit, which helps reduce hydrogen production costs. This method utilizes a molten liquid medium as both a heat transfer medium and a catalyst to directly crack methane within a liquid medium. Due to the unique properties of the liquid medium and its homogeneous catalytic capability, the active components are no longer confined to a specific region but are in a free-moving state, effectively avoiding phenomena such as carbon deposition and catalyst deactivation common in traditional catalytic cracking. Simultaneously, the density difference between the molten liquid medium and the carbon products causes the carbon products to float on the surface of the liquid medium. When they accumulate to a certain height, they automatically overflow into the transition zone, achieving automatic separation and enrichment of the carbon products and ensuring the continuous and stable progress of the reaction.

[0008] By employing a novel energy supply method to provide the necessary energy for methane cracking, zero CO2 emissions were achieved during the energy supply process. Simultaneously, the methane cracking reaction itself does not produce any CO. x This achieves near-zero CO2 emissions for the entire process. The invention utilizes the excellent thermal conductivity, fluidity, and catalytic capacity of the molten liquid medium to effectively solve the problems of high energy consumption, low conversion rate, and catalyst deactivation associated with traditional direct thermal or catalytic cracking of methane. It also avoids the high carbon emissions and low added value of steam methane reforming for hydrogen production. By setting up a methane cracking reaction zone and a carbon product storage transition zone, automatic and continuous separation of solid carbon particles is achieved, ensuring the continuous, stable, and safe operation of the entire unit. This solves the problems of high carbon emissions, high energy consumption, easy catalyst deactivation, and difficulty in separating carbon products in existing hydrogen production technologies.

[0009] Furthermore, the circulating functional mechanism includes a cyclone separator, a return valve A, a fuel reactor, and a return valve B connected in sequence. The air reactor is connected to the cyclone separator, and the return valve B is connected to the air reactor. The fuel reactor has a second top outlet in its upper middle part and a gaseous fuel inlet in its lower part. The cyclone separator has a first top outlet at its top. The air reactor, cyclone separator, return valve A, fuel reactor, return valve B, and air reactor form a loop. Oxygen carrier particles a circulate in these devices to achieve lattice oxygen transfer and regeneration. The energy released by the oxidation of the reduced oxygen carrier particles in the air reactor supplies the methane cracking reaction zone to maintain the energy required for the cracking reaction. Specifically, the energy released by the reaction supplies the catalytic medium, keeping it in a molten liquid phase state to promote the cracking of methane in its liquid phase medium.

[0010] Fuel reactor:

[0011] Fuel+MeO(s)→CO2(g)+H2O(g)+Me(s)ΔH<0;

[0012] Air reactor:

[0013] Me(s)+Air(g)→MeO(s)+N2(g)ΔH<0.

[0014] Furthermore, the bottom of the return valve A is provided with a first steam inlet, and the bottom of the return valve B is provided with a second steam inlet. The purpose of introducing steam through the first steam inlet is to blow up the oxygen carrier particles a inside the return valve A, so that they can flow into the fuel reactor. The purpose of introducing steam through the second steam inlet is to blow up the reduced oxygen carrier particles inside the return valve B, so that they can flow into the air reactor.

[0015] Furthermore, the air reactor has a cylindrical structure with an air inlet at the bottom and an air distribution plate at the lower part of the reactor. Air 'a' enters through the air inlet and then flows into the air reactor through the air distribution plate, where it comes into full contact with the reduced oxygen carrier particles (Me), achieving the oxidative regeneration of the oxygen carrier particles 'a' (MeO) and releasing a large amount of heat. The internal reaction is Air + Me → MeO + N2. The temperature of the methane cracking reaction zone is adjusted by controlling the amount of air 'a' input. The oxidized and regenerated oxygen carrier particles 'a' are carried by a high-speed airflow into a cyclone separator for gas-solid separation. The oxygen-deficient air is discharged from the first top outlet of the cyclone separator, while the oxygen carrier particles 'a' flow into the bottom of the cyclone separator under the influence of gravity. Under the action of the return valve A, they enter the fuel reactor and react with the introduced gaseous fuel. The gaseous fuel is oxidized into CO2 and H2O, and the oxygen carrier particles 'a' are reduced to Me. The internal reaction is C xH y +zMeO→xCO2+y / 2H2O+zMe; The exhaust gas is discharged through the second top outlet of the fuel reactor. Pure CO2 can be obtained through simple steam condensation, eliminating the need for an additional carbon capture device. The reduced oxygen carrier particles Me flow back into the air reactor under the action of the return valve B, forming a loop and achieving the regeneration and recycling of the oxygen carrier. The entire energy supply process decomposes the traditional combustion method into two reactions: oxidation and reduction, which are carried out separately in the air reactor and the fuel reactor. Oxygen carrier particles a and reduced oxygen carrier particles circulate between the air reactor and the fuel reactor to achieve lattice oxygen transfer and regeneration. Due to the absence of N2 dilution, the CO2 concentration is high, and CO2 and H2O can be separated through simple condensation to obtain nearly pure CO2. This achieves intrinsic carbon dioxide separation with little or no additional energy, while also reducing the investment cost of CO2 separation equipment.

[0016] Furthermore, the air reactor contains reduced oxygen carrier particles, which are one or more of Fe, Ni, Cu and Mn.

[0017] Furthermore, the bottom of the gas delivery pipe is connected to a porous distributor, which is triangular, square, circular, or irregular in shape. The porous distributor reduces the size of the output bubbles and enhances the effective heat transfer surface area of ​​the gas-liquid contact.

[0018] Furthermore, at least one porous sieve plate is installed in the center of the methane cracking reaction zone. The porous sieve plate is used to split the size of the rising bubbles. The pore size of the porous sieve plate should not be too small to prevent carbon particles generated by the cracking reaction from clogging the pores. Under the action of the porous distributor, the input gas is turned into small bubbles. The bubbles expand continuously during their ascent and undergo cracking reaction. The expanded bubbles are then split into smaller bubbles under the action of the porous sieve plate. This increases the gas-liquid contact area and slows down the bubble rising rate, prolonging the reaction time. This is beneficial for improving the feed conversion rate and product yield. It is important to note that the pores of the porous sieve plate should not be too small to prevent carbon particles generated by the cracking reaction from clogging the pores.

[0019] Furthermore, the methane cracking reactor contains a molten liquid phase medium, the filling height of which is lower than the upper part of the air reactor. This molten liquid phase medium is a mixture of elemental metal and metal salt, a mixture of metal alloy and metal salt, or a mixture of elemental metal, metal alloy, and metal salt. The mixture forms a two-phase or multi-phase liquid layer, and its melting point is 200-1500℃. The stratification is mainly due to density differences; the density of molten metal is higher than that of molten salt, which is higher than that of carbon materials.

[0020] Furthermore, the fuel supplied to the fuel reactor is one or more of methane, ethane, propane, butane, and natural gas.

[0021] Furthermore, the fuel supplied to the fuel reactor is C. x H y Or C x H y O z One or more combinations of gaseous fuels.

[0022] Furthermore, the gas separator is a membrane separator and / or a pressure swing adsorption separator.

[0023] In the technical solution of this application, the cracking energy of the methane cracking reactor is provided by the oxidation and regeneration of reduced oxygen carrier particles (Me) in the air reactor, and the provided temperature is ≤1600℃.

[0024] The temperature of the methane cracking reaction zone can be adjusted by regulating the flow rate of air input to the air reactor and the fuel supplied to the fuel reactor.

[0025] The beneficial effects of this invention are as follows:

[0026] 1. In the device of the present invention, the carbon product generated in the reaction zone accumulates on the surface of the liquid medium. When it accumulates to a certain height, the solid carbon product overflows from the reaction zone to the transition zone, realizing the automatic separation of carbon products in the device and ensuring the continuous and stable operation of the process. The carbon product accumulated in the transition zone is extracted from the lower opening of the reaction tank by an external vacuum pump.

[0027] 2. The traditional direct combustion energy supply is decomposed into two independent processes, which are carried out in a fuel reactor and an air reactor respectively. The oxygen carrier (MeO) circulates between the two reactors to achieve lattice oxygen transfer and regeneration. Due to the lack of N2 dilution, the products in the fuel reactor are mainly CO2 and H2O. After steam condensation and separation, relatively pure CO2 can be obtained without the need for additional complex separation and purification devices. This invention can continuously and stably output hydrogen and carbon products, improve the service life of liquid metal, and achieve near-zero CO2 emissions in the entire pyrolysis and energy supply process.

[0028] 3. The unique properties of the molten liquid phase catalytic medium and its homogeneous catalytic capability mean that its active components are no longer confined to a specific area but are in a free-moving state, effectively avoiding carbon deposition and catalyst deactivation phenomena common in traditional catalytic cracking. Simultaneously, the generated solid carbon product, due to its much lower density than the molten liquid phase medium, spontaneously floats on the surface of the liquid phase medium, effectively isolating the solid carbon product from the molten liquid phase catalytic medium, further avoiding the aforementioned catalyst deactivation problem caused by carbon accumulation on the active surface.

[0029] 4. Add a porous sieve plate to the reaction vessel. When bubbles pass through the sieve plate, they will break into several small bubbles, thereby reducing the size of the bubbles and increasing their gas-liquid contact area. At the same time, the gas rising rate is slowed down, which helps to prolong the reaction time and make the reaction more complete and thorough.

[0030] 5. In the methane cracking reaction, no oxygen is involved in the entire process, resulting in no CO being produced during the reaction. X The process generates compounds, with the product being only solid carbon, resulting in no direct CO2 emissions. Furthermore, the production of hydrogen also yields value-added carbon materials, which helps reduce hydrogen production costs and improve techno-economic efficiency.

[0031] 6. For molten liquid media, the combination of molten metal and molten salt effectively reduces metal contamination in carbon products and reduces the cost of subsequent separation and purification treatment. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of a near-zero CO2 emission hydrogen and solid carbon cogeneration device.

[0033] Figure 2 This is a schematic diagram of a methane cracking reactor and an air-embedded reactor.

[0034] Figure 3 This is a schematic diagram of a porous sieve plate embedded in the methane cracking reaction zone;

[0035] Figure 4 This is a schematic diagram of the air reactor and its circulating mechanism.

[0036] Reference numerals: 1-Methane cracking reaction zone, 2-Methane cracking reactor, 3-Air reactor, 4-Solid carbon particles, 5-Gas delivery pipe, 6-First top outlet, 7-Cyclone separator, 8-Fuel reactor, 9-Second top outlet, 10-Gaseous fuel inlet, 11-Air a, 12-Carbon extraction hole, 13-Porous distributor, 14-Porous sieve plate, 15-Molten liquid phase medium, 16-Filter, 17-Carbon product storage transition zone, 18-Unreacted gas, 19-Gas separator, 20-Hydrogen, 21-Air distribution plate, 22-Reduced oxygen carrier particles, 23-Oxygen carrier particles a, 24-Return valve A, 25-First steam inlet, 26-Second steam inlet, 27-Return valve B. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0038] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0039] Example 1

[0040] like Figures 1 to 4 As shown, this embodiment provides a near-zero CO2 emission hydrogen and solid carbon co-production device, including a methane cracking reactor 2. The methane cracking reactor 2 has a methane cracking reaction zone 1 inside. A carbon product storage transition zone 17 is provided between the methane cracking reactor 2 and the methane cracking reaction zone 1. The top of the methane cracking reaction zone 1 is located in the upper middle part of the methane cracking reactor 2. An air reactor 3 is provided in the middle of the methane cracking reaction zone 1. The top of the air reactor 3 is level with the top of the methane cracking reactor 2. A gas supply pipe 5 is provided inside the methane cracking reaction zone 1, extending to the outside of the methane cracking reactor 2. A filter 16 and a gas separator 19 are sequentially connected to the top of the methane cracking reactor 2. The air reactor 3 is connected to a circulation mechanism. In the technical solution of this application, the air reactor 3 is embedded in the methane cracking reaction zone 1, mainly providing energy for the methane cracking reaction process. The methane cracking reactor 2 is equipped with the methane cracking reaction zone 1 inside, and a carbon product storage transition zone 17 is provided between the methane cracking reactor 2 and the methane cracking reaction zone 1. The top of the methane cracking reaction zone 1 is located in the upper middle part of the methane cracking reactor 2, and the feed gas (methane and / or C) is used for the reaction. x H yThe gas enters the bottom of the methane cracking reaction zone 1 through the gas supply pipe 5. The methane cracking reaction zone 1 contains a certain amount of molten liquid medium 15. The generated solid carbon particles 4 (which can be graphene, carbon nanotubes, carbon black, carbon spheres, etc., depending on the liquid catalytic medium used and the reaction temperature) have a significant density difference with the molten liquid medium 15, causing them to float on the surface of the liquid medium. When the solid carbon particles 4 generated in the methane cracking reaction zone 1 accumulate to a certain height, they automatically overflow from the reaction zone and flow into the carbon product storage transition zone 17. The bottom outer periphery of the methane cracking reactor 2 is provided with carbon extraction holes 12. Under the action of a vacuum pump, the solid carbon particles 4 are extracted from the carbon extraction holes 12. The gas is extracted through orifice 12; the gas from the methane cracking reactor 2 is filtered by filter 16, which separates the carbon particles entrained in the gas components and recovers the separated solid carbon particles 4. The gas components then continue into the gas separator 19 to obtain high-purity hydrogen 20, while the separated unreacted gas 18 can be recycled back to the methane cracking reactor 2 as feedstock or back to the fuel reactor 8 as fuel. The entire cracking process achieves automatic and continuous separation of carbon products. By combining with a new energy supply method, the entire cracking reaction and energy supply process achieves near-zero CO2 emissions. Furthermore, the co-production of hydrogen 20 and solid carbon products significantly improves the system's energy utilization efficiency compared to traditional hydrogen and carbon production processes, reducing the carbon emissions per unit output energy while also reducing indirect greenhouse gas emissions from fuel supply consumption. Moreover, the produced carbon products can be sold for profit, which helps reduce the production cost of hydrogen 20. The molten liquid medium 15 serves as both a heat transfer medium and a catalyst, enabling the direct cracking of methane within the liquid medium. Due to the unique properties of the liquid medium and its homogeneous catalytic capability, the active components are no longer confined to a specific region but are in a free-moving state, effectively avoiding phenomena such as carbon deposition and catalyst deactivation common in traditional catalytic cracking. Simultaneously, the density difference between the molten liquid medium 15 and the carbon products causes the carbon products to float on the surface of the liquid medium. When they accumulate to a certain height, they automatically overflow into the transition zone, achieving automatic separation and enrichment of the carbon products and ensuring the continuous and stable progress of the reaction.

[0041] By employing a novel energy supply method to provide the necessary energy for methane cracking, zero CO2 emissions were achieved during the energy supply process. Simultaneously, the methane cracking reaction itself does not produce any CO. xThis achieves near-zero CO2 emissions for the entire process. The invention utilizes the excellent thermal conductivity, fluidity, and catalytic capacity of the molten liquid medium 15 to effectively solve the problems of high energy consumption, low conversion rate, and catalyst deactivation associated with traditional direct thermal cracking or catalytic cracking of methane, avoiding the high carbon emissions and low added value of steam methane reforming for hydrogen production. By setting up a methane cracking reaction zone 1 and a carbon product storage transition zone 17, automatic and continuous separation of solid carbon particles 4 is achieved, ensuring the continuous, stable, and safe operation of the entire unit. This solves the problems of high carbon emissions, high energy consumption, easy catalyst deactivation, and difficulty in separating carbon products in existing hydrogen production technologies.

[0042] Example 2

[0043] like Figure 1 and 4 As shown, based on Embodiment 1, the circulating functional mechanism includes a cyclone separator 7, a return valve A24, a fuel reactor 8, and a return valve B27 connected in sequence. The air reactor 3 is connected to the cyclone separator 7, and the return valve B27 is connected to the air reactor 3. The fuel reactor 8 has a second top outlet 9 in its upper middle part and a gas fuel inlet 10 in its lower part. The cyclone separator 7 has a first top outlet 6 at its top. The return valve A24 has a first water vapor inlet 25 at its bottom, and the return valve B27 has a second water vapor inlet 26 at its bottom.

[0044] Air reactor 3, cyclone separator 7, return valve A24, fuel reactor 8, return valve B27 and air reactor 3 form a loop. Oxygen carrier particles a23 circulate in these devices to achieve lattice oxygen transfer and regeneration. The energy released by the oxidation of reduced oxygen carrier particles 22 in air reactor 3 supplies the methane cracking reaction zone 1 to maintain the energy required for the cracking reaction. Specifically, the energy released by the reaction supplies the catalytic medium to keep it in a molten liquid phase state to promote the cracking of methane in its liquid phase medium.

[0045] Fuel reactor 8:

[0046] Fuel+MeO(s)→CO2(g)+H2O(g)+Me(s)ΔH<0;

[0047] Air reactor 3:

[0048] Me(s)+Air(g)→MeO(s)+N2(g)ΔH<0;

[0049] The purpose of introducing steam from the first steam inlet 25 is to blow up the oxygen carrier particles a23 in the return valve A24 so that they can flow into the fuel reactor 8. The purpose of introducing steam from the second steam inlet 26 is to blow up the reduced oxygen carrier particles 22 in the return valve B27 so that they can flow into the air reactor 3.

[0050] Example 3

[0051] like Figure 4 As shown, based on Embodiment 1, the air reactor 3 has a cylindrical structure, an air inlet is provided at the bottom of the air reactor 3, and an air distribution plate 21 is provided in the lower part of the air reactor 3. Air a11 enters through the air inlet and is then fed into the air reactor 3 via the air distribution plate 21. It comes into full contact with the reduced oxygen carrier particles 22 (Me), achieving the oxidative regeneration of the oxygen carrier particles a23 (MeO) and releasing a large amount of heat. The internal reaction is Air + Me → MeO + N2. The temperature of the methane cracking reaction zone 1 is adjusted by controlling the amount of air a11 supplied. The oxidized and regenerated oxygen carrier particles a23 are carried by a high-speed airflow into the cyclone separator 7 for gas-solid separation. The oxygen-deficient air is discharged from the first top outlet 6 of the cyclone separator 7, while the oxygen carrier particles a23 flow into the bottom of the cyclone separator 7 under gravity. Under the action of the return valve A24, they enter the fuel reactor 8 and react with the introduced gaseous fuel. The gaseous fuel is oxidized into CO2 and H2O, and the oxygen carrier particles a23 are reduced to Me. The internal reaction is C x H y +zMeO→xCO2+y / 2H2O+zMe; The exhaust gas is discharged through the second top outlet 9 of the fuel reactor 8. Pure CO2 can be obtained through simple steam condensation, eliminating the need for an additional carbon capture device. The reduced oxygen carrier particles 22Me flow back into the air reactor 3 under the action of the return valve B27, forming a loop and realizing the regeneration and recycling of the oxygen carrier. The entire energy supply process decomposes the traditional combustion method into two reactions: oxidation and reduction, which are carried out in the air reactor 3 and the fuel reactor 8 respectively. Oxygen carrier particles a23 and reduced oxygen carrier particles 22 circulate between the air reactor 3 and the fuel reactor 8 to achieve lattice oxygen transfer and regeneration. Due to the absence of N2 dilution, the CO2 concentration is high, and CO2 and H2O can be separated through simple condensation to obtain nearly pure CO2. This achieves intrinsic carbon dioxide separation with little or no additional energy, while also reducing the investment cost of CO2 separation equipment.

[0052] The reduced oxygen carrier particles 22 are one or more of Fe, Ni, Cu and Mn.

[0053] The oxygen carrier particles a23 are one or a mixture of several of FeO, Fe2O3, NiO, CuO, Mn2O3, etc.

[0054] Example 4

[0055] like Figure 1 As shown in Example 1, the bottom of the gas supply pipe 5 is connected to a porous distributor 13, which is triangular, square, circular, or irregular in shape. At least one porous sieve plate 14 is provided in the center of the methane cracking reaction zone 1. Under the action of the porous distributor 13, the input gas becomes small bubbles. The bubbles expand continuously and undergo cracking reaction during their ascent. The expanded bubbles then split into smaller bubbles under the action of the porous sieve plate 14. This increases the gas-liquid contact area and slows down the bubble rising rate, prolonging the reaction time and improving the raw material conversion rate and product yield. It should be noted that the pores of the porous sieve plate 14 should not be too small to prevent carbon particles generated by the cracking reaction from clogging the pores.

[0056] Example 5

[0057] like Figure 1 As shown in Example 1, the methane cracking reactor 2 contains a molten liquid phase medium 15. The filling height of the molten liquid phase medium 15 is lower than the upper part of the air reactor 3. The molten liquid phase medium 15 is a mixture of elemental metal and metal salt, a mixture of metal alloy and metal salt, or a mixture of elemental metal, metal alloy, and metal salt. The mixture forms a two-phase or multi-phase liquid layer, and the melting point of the mixture is 200-1500℃. The stratification is mainly due to density differences; the density of molten metal is higher than that of molten salt, which is higher than that of carbon materials.

[0058] In the above embodiments, the fuel supplied to the fuel reactor 8 is one or more of methane, ethane, propane, butane, and natural gas;

[0059] The fuel supplied to the fuel reactor 8 is C. x H y Or C x H y O z One or more combinations of gaseous fuels;

[0060] Gas separator 19 is a membrane separation and / or pressure swing adsorption separation;

[0061] The methane cracking reactor 2 is filled with molten liquid phase medium 15, which can be a metal element, metal alloy, or metal salt with a melting point of 200℃ to 1500℃, or any combination thereof;

[0062] The solid carbon particles 4 generated by the methane cracking reactor 2 can be graphene, carbon nanotubes, carbon black, carbon spheres, etc., depending on the liquid-phase catalytic medium used and the reaction temperature.

Claims

1. A near-zero CO2 emission hydrogen and solid carbon cogeneration device, characterized in that, The system includes a methane cracking reactor (2), which has a methane cracking reaction zone (1) inside. A carbon product storage transition zone (17) is provided between the methane cracking reactor (2) and the methane cracking reaction zone (1). The top of the methane cracking reaction zone (1) is located in the upper middle part of the methane cracking reactor (2). An air reactor (3) is provided in the middle of the methane cracking reaction zone (1). The top of the air reactor (3) is level with the top of the methane cracking reactor (2). A gas supply pipe (5) extending to the outside of the methane cracking reactor (2) is provided in the methane cracking reaction zone (1). A filter (16) and a gas separator (19) are connected in sequence to the top of the methane cracking reactor (2). The air reactor (3) is connected to a circulation function mechanism. The circulating mechanism includes a cyclone separator (7), a return valve A (24), a fuel reactor (8), and a return valve B (27) connected in sequence. The air reactor (3) is connected to the cyclone separator (7), and the return valve B (27) is connected to the air reactor (3). The fuel reactor (8) has a second top outlet (9) in the upper middle part, a gas fuel inlet (10) in the lower part of the fuel reactor (8), and a first top outlet (6) in the top of the cyclone separator (7). The air reactor (3) has a cylindrical structure, and an air inlet is provided at the bottom of the air reactor (3). An air distribution plate (21) is provided in the lower part of the air reactor (3).

2. The near-zero CO2 emission hydrogen and solid carbon cogeneration device according to claim 1, characterized in that, The bottom of the return valve A (24) is provided with a first steam inlet (25), and the bottom of the return valve B (27) is provided with a second steam inlet (26).

3. The near-zero CO2 emission hydrogen and solid carbon cogeneration device according to claim 1, characterized in that, The air reactor (3) contains reduced oxygen carrier particles (22), which are one or more of Fe, Ni, Cu and Mn.

4. The near-zero CO2 emission hydrogen and solid carbon cogeneration device according to claim 1, characterized in that, The bottom of the gas pipe (5) is connected to a porous distributor (13), which is triangular, square, circular or irregular in shape.

5. A near-zero CO2 emission hydrogen and solid carbon cogeneration device according to claim 4, characterized in that, At least one porous sieve plate (14) is provided in the middle of the methane cracking reaction zone (1).

6. A near-zero CO2 emission hydrogen and solid carbon cogeneration device according to claim 1, characterized in that, The methane cracking reactor (2) contains a molten liquid phase medium (15), the filling height of which is lower than the upper part of the air reactor (3). The molten liquid phase medium (15) is a mixture of elemental metal and metal salt, a mixture of metal alloy and metal salt, or a mixture of elemental metal, metal alloy and metal salt. The mixture forms a two-phase or multi-phase liquid layer, and the melting point of the mixture is 200-1500℃.

7. A near-zero CO2 emission hydrogen and solid carbon cogeneration device according to claim 1, characterized in that, The fuel supplied to the fuel reactor (8) is one or more of methane, ethane, propane, butane, and natural gas.

8. A near-zero CO2 emission hydrogen and solid carbon cogeneration device according to claim 1, characterized in that, The gas separator (19) is a membrane separator and / or a pressure swing adsorption separator.

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