Natural gas cracking and decarburization hydrogen production and in-situ power generation device adopting rotary table and small hole distribution

Abstract

The invention relates to a rotary table small hole shunting natural gas cracking decarburization hydrogen production and in-situ power generation device, and aims to solve the problems of high methane cracking energy consumption, low methane conversion rate, difficulty in preparation of a high-quality carbon material, low hydrogen production efficiency, high storage and transportation safety risk and the like. The device is provided with a natural gas shunting turntable, so that methane is uniformly shunted into molten metal and is efficiently cracked, and a high-quality carbon product and hydrogen are prepared. Raw material airflow is subjected to three-stage preheating through a heat exchanger where hydrogen power generation flue gas, a carbon material at an outlet of a cracker and mixed gas (hydrogen and residual natural gas) are located. Extra heat loads needed by natural gas molten metal cracking are supplemented through hydrogen separated from cold exchange mixed gas in an in-situ power generation mode, and surplus hydrogen electricity is merged into a power grid. According to the device, waste heat and hydrogen energy are fully utilized for in-situ cyclic power generation, gas-liquid contact is enhanced, residual gas is subjected to cyclic cracking, and the reaction efficiency is improved, so that mass production of high-quality carbon materials is achieved through safe and efficient utilization of the hydrogen energy, and the market demand of the high-quality carbon materials is relieved.

Description

Technical Field

[0001] The present invention relates to the field of carbon material and hydrogen energy production and in-situ efficient utilization of hydrogen energy, and in particular to a process device and method for rotating disc small hole diversion natural gas cracking decarbonization hydrogen production and hydrogen in-situ power generation. Background Art

[0002] In the context of global energy transformation, clean, efficient and sustainable energy utilization has gradually become the focus of attention. As the cleanest fossil energy, the high-value clean utilization of natural gas is regarded as the most promising key technology in energy transformation. As an important cornerstone of energy structure transformation, hydrogen is considered to be an ideal clean energy because it does not produce CO2 when burned. Therefore, the development of natural gas cracking carbon materials and hydrogen technology is of great significance to promote the mass production and application of high-quality carbon materials and the transformation of energy structure to zero carbon and clean direction. Molten metal cracking methane carbon materials and hydrogen technology have significant advantages over traditional decarbonization hydrogen production methods. First, there are no CO and CO2 by-products in the implementation of this technology, and carbon materials such as graphite, graphene, carbon nanotubes and hydrogen are directly generated, eliminating greenhouse gas emissions. Secondly, the carbon materials generated by this technology are easy to separate and collect, and there will be no carbon deposition problems in catalysts and reaction equipment in other natural gas cracking hydrogen production processes. In addition, molten metal cracking technology also has the advantages of controllable reaction conditions and high product purity. In recent years, domestic and foreign scientific research institutions and enterprises have conducted a lot of research in the field of molten metal cracking methane carbon materials and have made significant progress. Studies have shown that by regulating the type of molten metal, reaction temperature, pressure and other conditions, effective control of natural gas cracking products (carbon materials and hydrogen) can be achieved. At the same time, with the continuous development of catalyst technology, the conversion rate and product selectivity of molten metal cracking of methane or natural gas are also constantly improving. Despite this, the current natural gas molten metal cracking still has problems such as uneven bubbling of gas flow through molten metal, insufficient gas-liquid contact, low conversion efficiency of cracking products, high safety risks and high costs for mass production of hydrogen storage and transportation. The reactor structure has a crucial influence on the uniform distribution of natural gas feed, the degree of gas-liquid contact, the residence time of bubbles, etc., which directly affects the production efficiency of carbon materials and hydrogen. Therefore, the optimization and improvement of the reactor structure is an important part of this technical process. In addition, the problem of safe and economical storage and transportation of large amounts of hydrogen produced by natural gas cracking has not yet been fundamentally solved. The reaction temperature of natural gas molten metal cracking is generally as high as about 1000°C, which requires a large amount of electricity to meet the high temperature conditions for heating natural gas. Therefore, the hydrogen produced by natural gas cracking is used as the raw material of hydrogen generators on site. It can not only convert hydrogen energy into electricity in situ and ensure the power supply for heating natural gas by high-temperature cracking of molten metal, but also eliminate the safety hazards of hydrogen storage and transportation. Surplus electricity can be incorporated into the national power grid to achieve efficient utilization of hydrogen energy in situ circulation.

[0003] Patent CN117427564A discloses a device for directly cracking natural gas using Cu, Bi alloy or Cu, Sn alloy or Cu, Bi, Sn alloy molten metal as catalyst. The device of the invention cannot achieve uniform bubble dispersion of natural gas in molten metal and full contact between gas and liquid, and controlling the bubble size can significantly improve the methane conversion rate. Therefore, the present invention provides a turntable small hole diversion natural gas molten metal cracking carbon material and hydrogen and its in-situ power generation device, aiming to fundamentally solve the outstanding problems existing in the prior art. Summary of the invention

[0004] In view of the problems faced by the current natural gas molten metal cracking method for preparing carbon materials and hydrogen, such as insufficient methane conversion, difficulty in producing high-value carbon materials, low hydrogen production efficiency, high storage and transportation costs, and great safety risks, the present invention provides a turntable small hole diversion natural gas molten metal cracking decarbonization hydrogen production and in-situ power generation device and method.

[0005] The present invention provides a device for decarbonizing hydrogen production by cracking natural gas and generating electricity by hydrogen in situ through a small hole diversion on a turntable, as well as a complete natural gas cracking process flow without CO2 emission. While producing hydrogen, a "carbon" product with high added value can also be removed. The separated and purified hydrogen is directly used as a fuel for a hydrogen generator, and then hydrogen power generation (referred to as hydrogen power) is used to in-situ heat the metal catalyst of the natural gas cracking reaction until it reaches a molten state and a constant temperature after the cracking reaction temperature, thereby realizing the cyclic and efficient utilization of hydrogen energy. The natural gas cracking hydrogen production and its power generation process are "zero carbon" emissions, and the surplus electricity can be incorporated into the national power grid. In addition, in the process of natural gas being diverted through the small holes of the turntable through the molten metal, uniform, dispersed, and size-controllable microbubbles will be formed, thereby effectively increasing the contact area and contact time between methane and the molten metal, greatly improving the methane conversion rate and the production efficiency and output of carbon materials and hydrogen.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A rotary disc small hole diversion natural gas molten metal cracking decarbonization hydrogen production and in-situ power generation device, specifically comprising a natural gas processing unit, a natural gas cracking reaction unit, a waste heat recovery unit and a hydrogen power generation unit;

[0008] The natural gas processing unit includes: a natural gas inlet pipeline and a natural gas purification unit, and the specific process of the natural gas purification unit depends on the composition and properties of the natural gas;

[0009] The natural gas cracking reaction unit comprises: a molten metal cracking reactor, a natural gas secondary and tertiary preheating heat exchanger, and a gas separation tank; the molten metal cracking reactor is respectively connected to the natural gas secondary preheating heat exchanger and the reactor feed valve; the gas separation tank is connected to the molten metal cracking reactor through the natural gas tertiary preheating heat exchanger; the molten metal cracking reactor is directly connected to the transformer and the hydrogen generator through its electric heating plate;

[0010] The molten metal cracking reactor specifically includes: a molten metal cracking reaction tank, a turntable with small holes, a motor, and an electric heating plate; wherein the natural gas cracking tank is divided into three parts: upper, middle, and lower parts according to the position of the molten catalytic medium, the lower part of the cracking tank is high-temperature molten metal, the middle part is molten salt, and the upper part is a gas space, and the carbon material produced by cracking floats above the molten salt solution; the motor is directly connected to the turntable with small holes; the heating plate is installed on the outside of the cracking tank, and its outside is fully insulated.

[0011] The rotating disk with small holes is a pancake-shaped structure with a closed upper part, a uniform track inside and small holes around. The outer layer of the rotating disk with small holes can be equipped with a rotatable shell with uniformly distributed small holes.

[0012] The waste heat recovery unit comprises: a raw gas inlet pipeline, a natural gas primary, secondary and tertiary preheating heat exchanger, an electric heater and a reactor feed valve; wherein the natural gas pipeline is sequentially connected to the natural gas purification unit, the natural gas primary, secondary and tertiary preheating heat exchanger, the electric heater and the reactor feed valve; the reactor feed valve is directly connected to the electric heater and the molten metal cracking reactor respectively; the natural gas primary preheating heat exchanger is respectively connected to the hydrogen generator and the natural gas secondary preheating heat exchanger; the natural gas tertiary preheating heat exchanger is respectively connected to the molten metal cracking reactor and the gas separation tank;

[0013] The hydrogen power generation unit comprises: a hydrogen generator, a main transformer, a sub-transformer, an electric heating plate, and a natural gas primary preheating heat exchanger; wherein the hydrogen generator is connected to the electric heating plate through the main transformer; the sub-transformer is connected to the hydrogen generator and the main transformer respectively;

[0014] Furthermore, in the above process, the natural gas purification unit in the natural gas processing unit is directly connected to the reactor feed valve.

[0015] A device and method for splitting natural gas by small holes on a turntable for cracking and decarbonizing hydrogen production and in-situ power generation, which utilizes the small holes on the turntable to split natural gas, and realizes efficient and economical preparation of carbon materials and hydrogen through a molten metal cracking and decarbonizing hydrogen production supporting system process; the specific steps are as follows:

[0016] (1) Natural gas processing: wet gas from the gas field is desulfurized and dehydrated by the natural gas purification unit to become dry purified gas (raw gas); the raw gas is divided into two routes. One route passes through the first, second and third stage natural gas preheating heat exchangers in sequence, and the cold raw gas is preheated through three-stage progressive heat exchange. If the required preheating temperature is insufficient, the electric heater can be turned on to assist in preheating the raw gas. Then, the raw gas is mixed with the cold natural gas through the reactor feed valve to adjust the temperature, and finally enters the molten metal cracker;

[0017] (2) Natural gas molten metal cracking process: the natural gas feedstock flows through the small holes on the turntable, and the outer casing of the turntable is adjusted to make the size and number of bubbles of the feedstock gas passing through the molten metal moderate; the motor is started to rotate the turntable with small holes, and the gas flow through the small holes is driven by the turntable to form dispersed, uniform, and size-controlled bubbles in the molten metal; then, under the action of the molten metal in the cracking tank, it is cracked into elemental carbon products and hydrogen; the carbon products pass through the molten salt on the upper layer of the molten metal to remove metal impurities on the carbon surface, and then are cooled by the natural gas secondary preheating heat exchanger to obtain high-purity, high-value-added carbon materials; at the same time, hydrogen and a small amount of incompletely cracked methane mixed gas flow out from the upper part of the reactor, pass through the three-stage heat exchanger and exchange with the feedstock gas preheated by two stages, and then enter the gas separation tank; the small amount of methane separated is re-integrated into the feedstock gas through the reactor feed valve and further cracked, and the separated hydrogen is generated in situ by the hydrogen generator; the hydrogen electricity is used to power and heat the molten metal cracking reactor through the main transformer, thereby realizing the efficient recycling of hydrogen energy;

[0018] (3) Waste heat recovery process: The high-temperature carbon-free flue gas generated during the power generation process of the hydrogen generator, the high-temperature carbon material discharged from the cracking reaction tank, and the high-temperature hydrogen-methane mixed gas all carry different thermal energies. They are gradually transferred to the raw gas through the first, second, and third stage preheating heat exchangers, so that the raw gas is fully preheated, thereby effectively saving the consumption of hydrogen and electricity and maximizing the energy utilization rate of the entire process system.

[0019] It can be seen from the above technical solution that the present invention has the following gain effects compared with the prior art:

[0020] (1) The special rotating disk with small holes is combined with the molten metal cracking hydrogen production reactor to improve the micro-bubble diffusion of natural gas in the molten metal, strengthen the gas-liquid contact degree, and improve the methane conversion rate;

[0021] (2) The turntable with small holes of a special structure can change the size and number of small holes by rotating the outer shell installed; the turntable with small holes is directly connected to the motor, and the speed of the turntable can be controlled by frequency modulation of the motor;

[0022] (3) The natural gas flows into the molten metal cracking reactor through the reactor feed valve in two ways, cold and hot, to achieve controllable regulation of the natural gas temperature before cracking;

[0023] (4) After the raw gas undergoes three-stage progressive heat exchange, the thermal enthalpy of the natural gas is increased, thereby improving the reaction efficiency; a small amount of unreacted natural gas after separation is re-integrated into the natural gas raw material, thereby improving the cracking conversion rate of methane in the natural gas;

[0024] (5) The entire process system has a carbon-free energy supply and mainly produces high value-added carbon materials. Pure hydrogen is used as a by-product to generate electricity on-site, which fundamentally solves the problems of high storage and transportation costs and high safety risks of hydrogen energy. It is both green, environmentally friendly, safe and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the implementation cases or technical solutions of the present invention, the accompanying drawings introduce the contents involved. The following drawings are only implementation cases of the present invention. For ordinary technicians in this field, other drawings may be obtained based on the provided drawings without creative work.

[0026] Figure 1 It is a schematic diagram of the process flow of the rotary disk small hole diversion natural gas molten metal cracking decarbonization hydrogen production and its power generation device.

[0027] Among them, in the figure:

[0028] 1- natural gas inlet pipeline; 2- natural gas purification unit; 3- natural gas primary preheating heat exchanger; 4- natural gas secondary preheating heat exchanger; 5- natural gas tertiary preheating heat exchanger; 6- electric heater; 7- reactor feed valve; 8- molten metal cracking reactor; 81- turntable with small holes; 82- electric motor; 83- natural gas cracking tank; 84- heating plate; 9- gas separation tank; 10- hydrogen generator; 11- main transformer; 12- auxiliary transformer.

[0029] Figure 2 It is a schematic diagram of the structure of a turntable with small holes.

[0030] Figure 3 It is a detachable cover with a turntable with a small hole. DETAILED DESCRIPTION

[0031] In combination with the appended Figure 1 , Attachment Figure 2 and attached Figure 3 , clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without making creative work achievements are all within the scope of protection of the present invention.

[0032] Example 1

[0033] A rotary disc small hole diversion natural gas molten metal cracking decarbonization hydrogen production and in-situ power generation device comprises a natural gas processing unit, a natural gas cracking reaction unit, a waste heat recovery unit and a hydrogen power generation unit.

[0034] The natural gas processing unit comprises: a natural gas pipeline, a natural gas inlet (1) and a natural gas purification unit (2), wherein the natural gas pipeline is connected to the natural gas inlet (1) and the natural gas purification unit (2) in sequence;

[0035] The natural gas cracking reaction unit comprises: a molten metal cracking reactor (8), a natural gas secondary preheating heat exchanger (4), a natural gas tertiary preheating heat exchanger (5), and a gas separation tank (9); the molten metal cracking reactor (8) is connected to the natural gas secondary preheating heat exchanger (4) and the reactor feed valve (7) respectively; the gas separation tank (9) is connected to the molten metal cracking reactor (8) via the natural gas tertiary preheating heat exchanger (5); the molten metal cracking reactor (8) is directly connected to the hydrogen generator (10) via a main transformer (11);

[0036] The molten metal cracking reactor specifically comprises: a molten metal cracking reaction tank (83), a rotating disk with small holes (81), a motor (82), and an electric heating plate (84); wherein the natural gas cracking tank (83) is divided into three parts, namely, upper, middle, and lower parts, according to the position of the molten catalytic medium; all parts outside the cracking tank are insulated; the lower part of the cracking tank is high-temperature molten metal, the middle part is molten salt, and the upper part is a gas space; the motor is directly connected to the rotating disk with small holes; and the heating plate is attached to the outer side of the cracking tank;

[0037] The rotating disk with small holes is a closed pancake-shaped structure with uniform tracks inside and small holes around it. The outer layer of the rotating disk with small holes can be equipped with a detachable and rotatable shell with different apertures and different numbers of openings, which is convenient for implementing the research on the required aperture and number of openings affecting the distribution law of airflow microbubbles.

[0038] The waste heat recovery unit comprises: a natural gas inlet (1), a natural gas purification unit (2), a natural gas primary preheating heat exchanger (3), a natural gas secondary preheating heat exchanger (4), a natural gas tertiary preheating heat exchanger (5), an electric heater (6), and a reactor feed valve (7); wherein the natural gas is sequentially connected to the natural gas purification unit (2), the natural gas primary preheating heat exchanger (3), the natural gas secondary preheating heat exchanger (4), the natural gas tertiary preheating heat exchanger (5), the electric heater (6), and the reactor feed valve (7) through the natural gas inlet (1); the reactor feed valve (7) is directly connected to the electric heater (6) and the molten metal cracking reaction device (8) respectively; the natural gas primary preheating heat exchanger (3) is respectively connected to the hydrogen generator (10) and the natural gas secondary preheating heat exchanger (4); the natural gas tertiary preheating heat exchanger (5) is respectively connected to the molten metal cracking device (8) and the gas separation tank (9);

[0039] The hydrogen power generation unit comprises: a hydrogen generator (10), a main transformer (11), a sub-transformer (12), an electric heating plate (84), and a natural gas primary preheating heat exchanger (3); wherein the hydrogen generator (10) is connected to the electric heating plate (84) via the main transformer (11); the sub-transformer (12) is respectively connected to the hydrogen generator (10) and the main transformer (11); and no carbon dioxide is emitted after the flue gas generated by the generator (10) is heat exchanged and cooled by the natural gas primary preheating heat exchanger (3);

[0040] To further optimize the above technical solution, in the above process, the natural gas purification unit (2) in the natural gas processing unit is directly connected to the reactor feed valve (7) to mix the cold natural gas with the hot natural gas, thereby achieving controllable adjustment of the natural gas temperature before cracking;

[0041] To further optimize the above technical solution, in the hydrogen power generation unit, the hydrogen separated from the gas separation tank (9) enters the generator (10) to burn and generate electricity, and the electric energy is used to heat the electric heating plate (84) of the molten metal cracking reaction device through the main transformer (11), and the surplus electric energy is connected to the power grid or other required scenarios through the auxiliary transformer (12).

[0042] Example 2

[0043] A method for producing hydrogen by cracking and decarbonizing natural gas and molten metal by rotating disc small hole diversion and a power generation device thereof, wherein the rotating disc small hole diversion natural gas molten metal cracker supporting system process is used to crack natural gas to prepare carbon materials and hydrogen; the specific steps are as follows:

[0044] (1) Natural gas processing: wet gas from the gas field is desulfurized and dehydrated by the natural gas purification unit (2) to become pure raw gas; the raw gas is divided into two paths, one path passes through the natural gas primary preheating heat exchanger (3), the natural gas secondary preheating heat exchanger (4), and the natural gas tertiary preheating heat exchanger (5) in sequence, and the room temperature raw gas is preheated by three-stage progressive heat exchange. If the required preheating temperature is insufficient, the electric heater (6) can be turned on to assist in preheating the raw gas. Then, the raw gas is mixed with cold natural gas through the reactor feed valve (7) to adjust the temperature to reach the required inlet reaction temperature, and finally enters the molten metal cracker (8);

[0045] (2) Molten metal cracking natural gas process: the high-temperature natural gas mixed with the natural gas purification unit (2) and the three-stage progressive preheating treatment flows into the rotating disk with small holes, the outer casing of the rotating disk with small holes is adjusted to control the aperture and number of outlet holes of the required methane microbubbles, the motor is started to rotate the rotating disk with small holes (81), and under the action of the rotating disk with small holes (81), dispersed, uniform and size-controllable natural gas microbubbles are formed; then, in the natural gas cracking tank (83), it reacts with the molten metal to generate a single carbon product and hydrogen with a small amount of methane; the carbon product passes through the molten salt on the upper layer of the molten metal to remove the metal impurities on the carbon surface, and then passes through the natural gas secondary preheating heat exchanger (4) to cool to obtain a high-purity and high-value-added carbon material; the generated gas product (hydrogen and a small amount of methane) flows out from the upper part of the reactor and passes through the natural gas three-stage preheating heat exchanger (4) to obtain a high-purity and high-value-added carbon material. The heat exchanger (5) cools the mixed gas, and the cooled mixed gas is passed into a gas separation tank (9) to separate hydrogen and a small amount of unreacted methane, and the separated small amount of methane re-enters the reactor feed valve (7) for cyclic cracking; the separated hydrogen is passed into a hydrogen generator to generate electricity, and the hydrogen electricity is regulated by a main transformer (11) and acts on a heating plate (84) of a molten metal cracking hydrogen production reactor, and the electricity generated by hydrogen combustion is used to provide energy for the reactor internal system, thereby realizing efficient cyclic utilization of hydrogen energy; the hydrogen electricity generated by the hydrogen generator (10) is used to heat the molten metal cracking reactor (8), and the flue gas of the hydrogen generator is passed into a natural gas primary preheating heat exchanger (3) to cool without carbon dioxide emission; the heat emitted by the flue gas is used for primary preheating of cold natural gas, thereby improving the energy utilization rate of the entire process system.

[0046] Each embodiment in this specification is described in a progressive manner. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part. The technical solution and the inventive concept of the present invention are equivalently replaced or changed, which belongs to the protection scope of the present invention.

Claims

1. A rotary disc small hole diversion natural gas cracking decarbonization hydrogen production and in-situ power generation device, characterized in that: It includes a natural gas processing unit, a natural gas cracking reaction unit, a waste heat recovery unit and a hydrogen power generation unit.

2. The natural gas processing unit according to claim 1, characterized in that: include: A natural gas inlet pipeline is connected to a natural gas purification unit. The specific process of the natural gas purification unit depends on the composition and properties of the natural gas. The natural gas inlet pipeline is connected to the natural gas purification unit. The natural gas purification unit is directly connected to the reactor feed valve.

3. The natural gas cracking reaction unit according to claim 1, characterized in that: include: Molten metal cracking reactor, natural gas secondary and tertiary preheating heat exchangers and a gas separation tank; the molten metal cracking reactor is respectively connected to the natural gas secondary preheating heat exchanger and the reactor feed valve; the gas separation tank is connected to the molten metal cracking reactor through the natural gas tertiary preheating heat exchanger; the molten metal cracking reactor is directly connected to the transformer and the hydrogen generator through its electric heating plate.

4. The molten metal cracking reactor according to claim 3 specifically comprises: A molten metal cracking reaction tank, a turntable with small holes, a motor and an electric heating plate; wherein the natural gas cracking tank is divided into three parts: upper, middle and lower parts according to the position of the molten catalytic medium, the lower part of the cracking tank is high-temperature molten metal, the middle part is molten salt, the upper part is a gas space, and the carbon material produced by cracking floats above the molten salt solution; the motor is directly connected to the turntable with small holes; the heating plate is installed on the outside of the cracking tank, and its outside is fully insulated.

5. The rotating disk with small holes according to claim 4 is a pancake-shaped structure with a closed top, a uniform gas channel in the shell, and uniform small holes in the shell wall. The outer layer of the rotating disk with small holes can be equipped with a rotatable shell with uniformly distributed small holes of different numbers, hole types, and hole diameters as required (Figure 3 is only an example).

6. The waste heat recovery unit according to claim 1 comprises: Raw gas inlet pipeline, natural gas primary, secondary and tertiary preheating heat exchangers, electric heater and reactor feed valve; wherein the natural gas pipeline is sequentially connected with the natural gas purification unit, the natural gas primary, secondary and tertiary preheating heat exchangers, electric heater and reactor feed valve; the reactor feed valve is directly connected with the electric heater and the molten metal cracking reactor respectively; the natural gas primary preheating heat exchanger is respectively connected with the hydrogen generator and the natural gas secondary preheating heat exchanger; the natural gas tertiary preheating heat exchanger is respectively connected with the molten metal cracking reactor and the gas separation tank.

7. The hydrogen power generation unit according to claim 1, characterized in that: include: A hydrogen generator, a main transformer, a sub-transformer, an electric heating plate and a natural gas primary preheating heat exchanger; wherein the hydrogen generator is connected to the electric heating plate via the main transformer; The auxiliary transformer is connected to the hydrogen generator and the main transformer respectively.

8. A process device and method for rotating disc small hole diversion natural gas cracking decarbonization hydrogen production and in-situ power generation, characterized in that: The molten metal cracking reaction device supporting system and process described in claims 1 to 7 are used to crack natural gas to produce carbon materials and hydrogen; the specific steps are as follows: (1) Natural gas processing: The wet gas from the gas field is desulfurized and dehydrated by the natural gas processing unit to become dry purified gas (raw gas). The raw gas is divided into two routes. One route passes through the primary, secondary and tertiary natural gas preheating heat exchangers in sequence. The cold raw gas is preheated through three-stage progressive heat exchange. If the required preheating temperature is insufficient, the electric heater can be turned on to assist in preheating the raw gas. Then, the raw gas is mixed with the cold natural gas through the reactor feed valve to adjust the temperature, and finally enters the molten metal cracker. (2) Natural gas molten metal cracking decarbonization hydrogen production and in-situ power generation process: Before the natural gas flows through the gas channel in the turntable, the outer casing of the turntable is adjusted to make the size and number of bubbles of the raw gas passing through the molten metal moderate; the motor is started to rotate the turntable with small holes, and the gas flow through the small holes is driven by the turntable to form dispersed, uniform, and size-controlled bubbles in the molten metal; then, under the action of the molten metal in the cracking tank, it is cracked into elemental carbon products and hydrogen; The carbon product passes through the molten salt on the upper layer of the molten metal to remove the metal impurities on the carbon surface, and then is cooled through the natural gas secondary preheating heat exchanger to obtain high-purity, high-value-added carbon materials; at the same time, hydrogen and a small amount of incompletely cracked methane mixed gas flow out from the upper part of the reactor, pass through the three-stage heat exchanger and cool with the two-stage preheated raw gas, and then enter the gas separation tank; the small amount of methane separated is merged into the raw gas through the reactor feed valve and further cracked, and the separated hydrogen is used to generate electricity in situ through the hydrogen generator; the hydrogen and electricity are used to power and heat the molten metal cracking reactor through the main transformer, and the carbon-free flue gas after the hydrogen generator generates electricity is cooled by the natural gas primary preheating heat exchanger without carbon emissions; the heat energy in the flue gas is used for the primary preheating of the raw gas, thereby improving the energy utilization rate of the entire process system.

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