Fused bed coal gasification reaction apparatus based on inductive heating and method of use thereof

Abstract

The application discloses a molten bed coal gasification reaction device based on an induction heating mode and a use method thereof, and relates to the technical field of energy utilization. The device comprises an electromagnetic induction heating system and a molten bed reactor. The electromagnetic induction heating system comprises an electromagnetic induction heating coil, which is wrapped on the outer wall of the reactor cylinder and is used for passing in electric energy and generating a high-frequency alternating magnetic field. The bed layer of the molten bed reactor is filled with molten salt and a magnetic conductive element. The inner cylinder wall of the molten bed reactor is provided with a magnetic conductive lining. The magnetic conductive element and the magnetic conductive lining generate eddy current heating under the action of the high-frequency alternating magnetic field, the molten salt is heated to 800 DEG C-1000 DEG C and is melted to form a high-temperature molten bed. The application adopts the coupling mode of electromagnetic induction heating and a molten bed, can provide the heat source required by the gasification reaction by consuming low-quality green electricity, and realizes the purpose of storing low-quality green electricity by synthesizing chemicals by taking the synthesis gas obtained by the gasification reaction as raw materials.

Description

Technical Field

[0001] This invention belongs to the field of energy utilization technology, specifically, it relates to a molten bed coal gasification reactor based on induction heating and its usage method. Background Technology

[0002] With the continuous adjustment of my country's energy structure and the progress and cost reduction of new energy power generation technology, clean energy such as wind and solar energy has been developed on a large scale in recent years, and the installed capacity has increased rapidly. In the foreseeable future, my country's energy structure will be dominated by clean energy such as solar and wind energy, and the electricity price will be very cheap. How to make better use of clean energy will play a vital role in the development of the national economy.

[0003] Although coal as a primary energy source will decrease significantly, it remains an important raw material for chemical industries. How to effectively utilize abundant coal resources and develop advanced coal chemical technologies will impact the future of my country's energy and chemical industry. As a fundamental technology for coal conversion, gasification technology is one of the most important and critical processes in the development of coal chemical industry. Coal gasification is a thermochemical process that converts solid carbon into combustible gas under high-temperature conditions through the chemical action of a gasifying agent. In traditional coal gasification technologies, the heat required for this thermochemical process is maintained by the combustion of large amounts of carbon, which not only consumes a large amount of raw materials but also results in low carbon combustion efficiency, heavy pollution, and a series of environmental problems.

[0004] Existing mainstream coal gasification technologies, such as fixed bed, fluidized bed, entrained flow bed, and traditional molten bed, each have their own focus in terms of feedstock adaptability and syngas production. However, they all rely on the heat released from the combustion of a large amount of feedstock carbon to maintain the reaction temperature. This results in problems such as high feedstock consumption rate (20%-30% of feedstock carbon is required to maintain the temperature), low energy utilization efficiency (thermal efficiency of only 50%-60%), and significant pollution (large amounts of carbon emissions).

[0005] No effective solutions have yet been proposed to address the problems in the relevant technologies.

[0006] Therefore, in order to solve the above problems, the present invention provides a molten bed coal gasification reactor based on induction heating and its usage method. Summary of the Invention

[0007] In order to overcome the above-mentioned technical problems, the purpose of this invention is to provide a molten bed coal gasification reactor based on induction heating and its usage method.

[0008] The objective of this invention can be achieved through the following technical solutions: A molten bed coal gasification reactor based on induction heating includes an electromagnetic induction heating system and a molten bed reactor; The electromagnetic induction heating system includes an electromagnetic induction heating coil, which is wrapped around the outer wall of the reactor cylinder and is used to pass in electrical energy and generate a high-frequency alternating magnetic field. The bed of the molten bed reactor is filled with molten salt and magnetic elements. The inner wall of the molten bed reactor is provided with a magnetic lining. The magnetic elements and the magnetic lining generate eddy current heating under the action of a high-frequency alternating magnetic field, heating the molten salt to 800-1000℃ and melting it to form a high-temperature molten bed. The upper part of the molten bed reactor is provided with a feeding mechanism, and the upper side of the molten bed reactor is provided with a gas outlet pipe. The two sides of the cylinder wall of the molten bed reactor are respectively provided with a first ash overflow port and a second ash overflow port. The pulverized coal is transported to the surface of the high-temperature molten bed through the feeding mechanism, and reacts chemically with the gasifying agent to generate syngas. The syngas is discharged through the gas outlet pipe, and the ash is discharged through the ash overflow port.

[0009] As a preferred technical solution of the present invention, the cylindrical wall of the molten bed reactor consists of, from the inside out, a corrosion-resistant high-temperature coating, a magnetically conductive lining, an air film layer, a high-temperature alloy shell, a heat insulation layer, and an electromagnetic induction heating coil. The corrosion-resistant high-temperature coating is a high-temperature anti-corrosion, heat-conducting, and energy-saving nano-coating that can withstand temperatures above 1300℃ for a long time. The insulation layer is a non-magnetic material.

[0010] As a preferred embodiment of the present invention, the magnetically conductive liner is selected from one or more of high-purity graphite, silicon carbide, graphite-silicon carbide composite material, and silicon carbide-molybdenum dioxide composite material; the magnetically conductive element is a spherical, rod-shaped or other shaped magnetically conductive heating metal material, which is mixed with molten salt in a preset volume ratio and filled into the bed.

[0011] As a preferred embodiment of the present invention, the molten salt is a binary carbonate molten salt, which has the characteristics of good thermal stability, low viscosity, high heat capacity and high thermal conductivity at high temperature, and has a catalytic effect on gasification reaction.

[0012] As a preferred embodiment of the present invention, the feeding mechanism includes a screw feeder, an air inlet pipe, and a conveying pipe. The air inlet pipe and the conveying pipe adopt a sleeve structure, with the conveying pipe located in the inner layer and having an opening on the bottom side wall, and the air inlet pipe located in the outer layer and having a trumpet-shaped bottom. The screw feeder adjusts its rotation speed through a stepper motor controller, thereby controlling the coal powder addition flow rate. Carrier gas is introduced through the air inlet pipe, and the trumpet-shaped structure at the bottom plays a role in purging and dispersing the coal powder, so that the coal powder is evenly sprayed onto the surface of the high-temperature molten bed through multiple openings in the conveying pipe.

[0013] As a preferred embodiment of the present invention, the gas film layer can introduce cooling gas, which can reduce the temperature of the high-temperature alloy shell to below 600°C without affecting the temperature stability of the high-temperature molten bed; the high-temperature alloy shell is made of a metal material with general magnetic properties, which can meet the requirements of high-temperature and high-pressure experiments at 1000°C and 2MPa pressure.

[0014] As a preferred embodiment of the present invention, it further includes a temperature closed-loop control system disposed on the molten bed reactor and electrically connected to the electromagnetic induction heating coil. The temperature closed-loop control system includes a contact thermocouple probe and a PLC control system. The contact thermocouple probe extends into the high-temperature molten bed to accurately measure the bed temperature and transmit the data to the PLC control system. The PLC control system compares the actual temperature with a preset target value and achieves dynamic and precise adjustment of the bed temperature by adjusting the output power of the electromagnetic induction heating coil, with a temperature control accuracy of ±1%.

[0015] As a preferred embodiment of the present invention, a portion of the carrier gas can be replaced by a gasifying agent, which reacts with the pulverized coal on the surface of the high-temperature molten bed. The first and second ash overflow ports are continuously discharged online, which is achieved by stopping the feeding, closing the valve of the gas outlet pipe, and opening the valves of the first and second ash overflow ports. During the discharge process, the temperature closed-loop control system adaptively adjusts the current of the electromagnetic induction heating coil according to the bed temperature change to maintain a stable bed temperature.

[0016] The method of using a molten bed coal gasification reactor based on induction heating includes the following steps: S1. Start the electromagnetic induction heating system. Use low-quality green electricity to drive the electromagnetic induction heating coil to generate a high-frequency alternating magnetic field, which causes the magnetic lining and magnetic elements to heat up with eddy currents, heating and melting the molten salt to form a high-temperature molten bed of 800℃-1000℃. S2. The bed temperature is stabilized at the preset target value through the temperature closed-loop control system, while cooling gas is introduced through the gas film layer to keep the temperature of the high-temperature alloy shell below 600℃ and adjust the pressure inside the reactor to 2MPa. S3. Start the feeding mechanism and adjust the coal powder feeding amount through the screw feeder. Under the action of the carrier gas, the coal powder is evenly sprayed onto the surface of the high-temperature molten bed. The coal powder and the gasifying agent react chemically to generate syngas, which is then discharged through the gas outlet pipe. S4. During the reaction, when the ash and slag accumulate to the preset amount, online slag discharge operation is performed; after the slag discharge is completed, the valves of the first ash and slag overflow port and the second ash and slag overflow port are closed, the valve of the synthesis gas outlet is opened, the feeding is resumed, and the unit is put into continuous operation.

[0017] As a preferred technical solution of the present invention, in S1, the electromagnetic induction heating system controls the heating energy input by adjusting the current of the electromagnetic induction heating coil. When the bed temperature is lower than the preset value, the current is increased, and when it is higher than the preset value, the current is decreased. In S3, the substitution ratio of the carrier gas and the gasifying agent can be flexibly adjusted according to the gasification reaction requirements to optimize the syngas yield and gas composition.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention employs electromagnetic induction heating coupled with a molten bed, which can provide the heat source required for the gasification reaction by consuming low-quality green electricity. By using the syngas obtained from the gasification reaction as a raw material to synthesize chemicals, the purpose of storing low-quality green electricity can be achieved.

[0019] 2. The reactor wall of the present invention adopts a multi-layer design of high temperature coating, magnetic lining, gas film layer, high temperature alloy layer and heat insulation layer, which can realize experimental conditions where the internal temperature of the molten bed is 1000℃ and the temperature of the metal cylinder wall is below 600℃. This allows gasification experiments to be carried out under high temperature and high pressure conditions, thus broadening the experimental range.

[0020] 3. The design of the mixed filling bed of multi-element molten salt and magnetic elements inside the molten bed of the present invention, as well as the advantages of molten salt with good thermal stability, low viscosity, high heat capacity and large thermal conductivity, can achieve a uniform, stable and controllable temperature field in the molten bed, and solve the problem of local high temperature of the heated element during induction heating.

[0021] 4. The overflow port design on both sides of the molten bed in this invention can achieve the purpose of online slag removal. Since the heat source is provided by induction heating, the gasification reaction process can be started and stopped at any time. Although the feeding will be stopped during the slag removal process, it will not affect the temperature of the bed.

[0022] 5. The molten salt used in this invention has a certain catalytic promoting effect on the gasification process, which can improve the gas yield, reduce the tar content in the gas, greatly increase the service life of the device, and reduce the production cost. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0025] Figure label: 1. Molten bed reactor; 2. Molten salt; 3. Magnetic element; 4. Electromagnetic induction heating coil; 5. Insulation layer; 6. High-temperature alloy shell; 7. Air film layer; 8. Magnetic lining; 9. Corrosion-resistant high-temperature coating; 10. Feeding mechanism; 11. First ash overflow port; 12. Second ash overflow port; 13. Air inlet pipe; 14. Air outlet pipe; 15. Screw feeder; 16. Conveying pipe. Detailed Implementation

[0026] The invention will now be further described with reference to the accompanying drawings and specific embodiments: Please see Figure 1 According to an embodiment of the present invention, a molten bed coal gasification reactor based on induction heating includes an electromagnetic induction heating system and a molten bed reactor 1. Please see Figure 1 The electromagnetic induction heating system includes an electromagnetic induction heating coil 4, which is wrapped around the outer wall of the reactor cylinder to supply electrical energy and generate a high-frequency alternating magnetic field. The bed of the molten bed reactor 1 is filled with molten salt 2 and magnetically conductive elements 3. The molten salt 2, filling the bed of the molten bed reactor 1, receives heat from the magnetically conductive lining 8 and the magnetically conductive elements 3, forming a high-temperature molten bed. Simultaneously, it catalyzes the coal powder gasification reaction. Its high heat capacity maintains a stable bed temperature, and its high thermal conductivity ensures a uniform temperature field. The catalytic effect accelerates the reaction and reduces tar. The inner wall of the molten bed reactor 1 is equipped with a magnetically conductive lining 8. The magnetic element 3 and the magnetic liner 8 generate eddy current heating under the action of a high-frequency alternating magnetic field, heating the molten salt 2 to 800-1000℃ and melting it to form a high-temperature molten bed. The molten bed reactor 1 serves as the core container for the coal powder gasification reaction, housing components such as the molten salt 2 and the magnetic element 3, and providing a high-temperature and high-pressure reaction environment. The electromagnetic induction heating coil 4 is wrapped around the outer wall of the cylinder of the molten bed reactor 1, using low-quality green electricity to generate a high-frequency alternating magnetic field, providing the magnetic field conditions for eddy current heating for the magnetic liner 8 and the magnetic element 3, converting green electricity into electromagnetic energy, and then converting it into thermal energy through eddy currents, thus realizing the directional conversion of "green electricity to thermal energy". Please see Figure 1 The upper part of the molten bed reactor 1 is equipped with a feeding mechanism 10, which can realize the precise delivery and uniform dispersion of pulverized coal, providing a stable raw material supply for the gasification reaction. The upper side of the molten bed reactor 1 is equipped with a gas outlet pipe 14. The two sides of the cylinder wall of the molten bed reactor 1 are respectively equipped with a first ash overflow port 11 and a second ash overflow port 12. The first ash overflow port 11 and the second ash overflow port 12 are used to discharge the ash generated by the reaction, realizing the continuous online discharge of ash, avoiding the accumulation of ash and affecting the bed temperature and reaction efficiency. Pulverized coal is transported to the surface of the high-temperature molten bed through the feeding mechanism 10, and reacts chemically with the gasifying agent to generate syngas. The syngas is discharged through the gas outlet pipe 14, and the ash is discharged through the ash overflow port.

[0027] Please see Figure 1 The cylindrical wall of the molten bed reactor 1 consists of, from the inside out, a corrosion-resistant high-temperature coating 9, a magnetically conductive lining 8, an air film layer 7, a high-temperature alloy shell 6, an insulation layer 5, and an electromagnetic induction heating coil 4. The corrosion-resistant high-temperature coating 9 prevents the molten salt 2 and the gasifying agent from eroding the magnetically conductive lining 8. The insulation layer 5 reduces heat loss from the bed. The air film layer 7 provides a protective channel for the subsequent high-temperature alloy shell 6. This design clarifies the hierarchical relationship of the cylindrical wall from the inside out, enabling the cylindrical wall to have a multi-layered synergistic capability of "high-temperature corrosion resistance - high-efficiency heat conduction - thermal insulation protection - pressure stability". Through hierarchical design, stable operation under high temperature and high pressure environment is achieved, which not only extends the overall service life of the device (the corrosion-resistant coating reduces losses) but also reduces heat waste (the insulation layer improves thermal efficiency). At the same time, the non-magnetically conductive insulation layer avoids interference with the magnetic field of the electromagnetic induction heating coil 4, ensuring heating efficiency. The corrosion-resistant high-temperature coating 9 is a high-temperature anti-corrosion, heat-conducting, and energy-saving nano-coating that can withstand temperatures above 1300℃ for a long time. The insulation layer 5 is a non-magnetically conductive material.

[0028] Please see Figure 1 The magnetic liner 8 is selected from one or more of high-purity graphite, silicon carbide, graphite-silicon carbide composite material, and silicon carbide-molybdenum dioxide composite material; the magnetic element 3 is a spherical, rod-shaped or other shaped magnetic heating metal material, which is mixed with molten salt 2 in a preset volume ratio and filled in the bed.

[0029] Please see Figure 1 Molten salt 2 is a binary carbonate molten salt. Binary carbonate molten salt has the characteristics of good thermal stability, low viscosity, high heat capacity and high thermal conductivity at high temperature. It also has a catalytic effect on gasification reaction. Compared with traditional bed materials (such as coke in fixed bed), the thermal stability of binary carbonate molten salt avoids decomposition at high temperature, the low viscosity reduces flow resistance, the high thermal conductivity ensures temperature uniformity, and the catalytic effect can improve the syngas yield, reduce tar content and reduce the cost of subsequent syngas purification, thus achieving the triple function of "heat storage-heat transfer-catalysis".

[0030] Please see Figure 1The feeding mechanism 10 includes a screw feeder 15, an air inlet pipe 13, and a conveying pipe 16. The air inlet pipe 13 and the conveying pipe 16 adopt a sleeve structure. The conveying pipe 16 is located in the inner layer and has an opening on the bottom side wall. The air inlet pipe 13 is located in the outer layer and has a trumpet-shaped bottom. The screw feeder 15 adjusts its speed through a stepper motor controller, thereby controlling the coal powder addition flow rate to accurately match the gasification load and avoid excessive or insufficient raw materials. The carrier gas is introduced through the air inlet pipe 13 and uses the trumpet-shaped structure at the bottom to purge and disperse the coal powder, so that the coal powder is evenly sprayed onto the surface of the high-temperature molten bed through multiple openings in the conveying pipe 16. The feeding mechanism 10 can achieve "precise quantity control - uniform dispersion - stable conveying" of coal powder: the screw feeder 15 controls the feeding amount to match the gasification load, the trumpet-shaped bottom of the air inlet pipe 13 forms a uniform purging force on the coal powder, and the multiple openings in the conveying pipe 16 make the coal powder evenly sprayed onto the surface of the molten salt 2. This solves the problem of "coal powder agglomeration and uneven feeding" in traditional feeding methods.

[0031] Please see Figure 1 The gas film layer 7 can introduce cooling gas, which can reduce the temperature of the high-temperature alloy shell 6 to below 600℃ without affecting the temperature stability of the high-temperature molten bed. The high-temperature alloy shell 6 is made of a metal material with general magnetic permeability, which can meet the high-temperature and high-pressure experimental requirements at 1000℃ and 2MPa. The gas film layer 7 isolates the high temperature of the magnetically conductive liner 8 through the cooling gas, protecting the structural strength of the high-temperature alloy shell 6 under high pressure and preventing the shell strength from decreasing due to high temperature. The high-temperature alloy shell 6 provides a high-pressure sealing environment of 2MPa for the device, which is suitable for high-temperature and high-pressure gasification requirements. It achieves the synergy of "high-temperature reaction environment" and "low-temperature shell protection" - the cooling gas only acts on the shell and does not affect the temperature stability of the molten bed. It ensures the high-temperature requirements of the core reaction and avoids the shell from being damaged by high temperature. At the same time, the material with general magnetic permeability reduces the shell's own eddy current heating, reduces additional energy loss, and broadens the experimental and application range of the device.

[0032] Please see Figure 1 It also includes a temperature closed-loop control system installed on the molten bed reactor 1 and electrically connected to the electromagnetic induction heating coil 4. The temperature closed-loop control system includes a contact thermocouple probe and a PLC control system. The contact thermocouple probe extends into the high-temperature molten bed to accurately measure the bed temperature and transmit the data to the PLC control system. The PLC control system compares the actual temperature with the preset target value and achieves dynamic and precise adjustment of the bed temperature by adjusting the output power of the electromagnetic induction heating coil 4. The temperature control accuracy is ±1%.

[0033] Please see Figure 1A portion of the carrier gas can be replaced by a gasifying agent, which reacts with the pulverized coal on the surface of the high-temperature molten bed. The first ash overflow port 11 and the second ash overflow port 12 are discharged online continuously. The discharge is achieved by stopping the feeding, closing the valve of the gas outlet pipe 14, and opening the valves of the first ash overflow port 11 and the second ash overflow port 12. During the discharge process, the temperature closed-loop control system adaptively adjusts the current of the electromagnetic induction heating coil 4 according to the bed temperature change to maintain the bed temperature stability.

[0034] The method of using a molten bed coal gasification reactor based on induction heating includes the following steps: S1. Start the electromagnetic induction heating system and use low-quality green electricity to drive the electromagnetic induction heating coil 4 to generate a high-frequency alternating magnetic field, which causes the magnetic liner 8 and the magnetic element 3 to heat up in the eddy current, heating and melting the molten salt 2 to form a high-temperature molten bed of 800℃-1000℃. S2. The bed temperature is stabilized at the preset target value through the temperature closed-loop control system, and cooling gas is introduced through the gas film layer 7 to keep the temperature of the high-temperature alloy shell 6 below 600℃ and adjust the pressure inside the reactor to 2MPa. S3. Start the feeding mechanism 10, and adjust the coal powder feeding amount through the screw feeder 15. Under the action of the carrier gas, the coal powder is evenly sprayed onto the surface of the high-temperature molten bed. The coal powder and the gasifying agent react chemically to generate syngas, and the syngas is discharged through the gas outlet pipe 14. S4. During the reaction, when the ash and slag accumulate to the preset amount, online slag discharge operation is performed; after the slag discharge is completed, the valves of the first ash and slag overflow port 11 and the second ash and slag overflow port 12 are closed, the valve of the synthesis gas outlet 14 is opened, the feeding is resumed, and the device is put into continuous operation.

[0035] Specifically, in S1, the electromagnetic induction heating system controls the heating energy input by adjusting the current of the electromagnetic induction heating coil 4. When the bed temperature is lower than the preset value, the current is increased, and when it is higher than the preset value, the current is decreased. In S3, the substitution ratio of carrier gas and gasifying agent can be flexibly adjusted according to the gasification reaction requirements to optimize the syngas yield and gas composition.

[0036] The working principle of the molten bed coal gasification reactor based on induction heating in this invention patent is as follows: First, the electromagnetic induction heating system is started, using low-quality green electricity that cannot be connected to the Internet to power the electromagnetic induction heating coil 4. The electromagnetic induction heating coil 4 is wrapped around the outer wall of the molten bed reactor 1. After being energized, it generates a high-frequency alternating magnetic field. The magnetic lining 8 and the magnetic element 3 within the magnetic field range generate eddy currents inside due to the electromagnetic induction effect. The eddy currents are converted into heat energy under the action of the material's own resistance, causing the temperature of the magnetic lining 8 and the magnetic element 3 to rise rapidly to 800℃-1000℃. Subsequently, heat is transferred to the molten binary carbonate 2 in the bed through direct contact. The molten salt 2 absorbs heat and melts to form a high-temperature molten bed. During this process, the insulation layer 5 wraps around the outside of the high-temperature alloy shell 6, effectively reducing the heat loss from the bed and ensuring thermal efficiency. At the same time, the gas film layer 7 introduces cooling gas to reduce the temperature of the high-temperature alloy shell 6 to below 600°C. Combined with the pressure-bearing capacity of the high-temperature alloy shell 6, a high-temperature and high-pressure environment of 1000°C and 2MPa is formed inside the reactor to meet the requirements of the gasification reaction. The temperature closed-loop control system starts synchronously: a contact thermocouple probe is inserted into the high-temperature molten bed to collect the bed temperature in real time and transmit the electrical signal to the PLC control system; the PLC control system compares the actual temperature with the preset target value. If the actual temperature is lower than the preset value, the output signal increases the output power of the electromagnetic induction heating coil 4 to increase the heat input; if the actual temperature is higher than the preset value, the output power is reduced to reduce the heat input. Through closed-loop logic, the bed temperature is precisely controlled within ±1%, ensuring a stable reaction environment. Once the temperature and pressure reach the preset conditions, the feeding mechanism 10 is activated: the screw feeder 15 adjusts the speed through the stepper motor controller to control the coal powder addition flow rate, and the coal powder enters the conveying pipe 16; at the same time, the carrier gas is introduced through the air inlet pipe 13, and the horn-shaped structure at the bottom of the air inlet pipe 13 forms a uniform blowing force on the coal powder in the conveying pipe 16, so that the coal powder is evenly sprayed onto the surface of the high-temperature molten bed through multiple openings at the bottom of the conveying pipe 16. After the pulverized coal comes into contact with the high-temperature molten salt 2, it undergoes a rapid gasification reaction with the gasifying agent under the high-temperature heating and catalytic action of the molten salt 2, generating syngas mainly composed of CO and H2. Due to its low density, the syngas flows upward and is discharged through the syngas outlet 14 on the upper side of the molten bed reactor 1, serving as a raw material for subsequent chemical production, thus realizing the conversion and storage of "green electricity-thermal energy-chemical energy". The ash generated during the reaction gradually accumulates in the bed. When the amount of ash reaches the preset value, an online ash discharge operation is performed: the feeding mechanism 10 is stopped, the valve of the syngas outlet 14 is closed, and the valves of the first ash overflow port 11 and the second ash overflow port 12 are opened. The ash is discharged through the overflow port under the action of gravity. During the ash discharge process, the temperature closed-loop control system monitors the bed temperature in real time and maintains the temperature stability by adjusting the current of the electromagnetic induction heating coil 4 to avoid temperature fluctuations. After the ash discharge is completed, the overflow port valve is closed, the valve of the syngas outlet 14 is opened, the feeding mechanism 10 is restarted to resume feeding, and the device continues to enter the continuous gasification stage.

[0037] The entire process, through the coupling of electromagnetic induction heating and the molten bed, not only absorbs low-quality green electricity but also avoids the carbon emission problems of traditional gasification technology that burns raw materials for energy. At the same time, it achieves efficient and continuous gasification of pulverized coal, thus achieving the technical goal of increasing efficiency and reducing carbon emissions.

[0038] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0039] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A molten bed coal gasification reactor based on induction heating, characterized in that, Including an electromagnetic induction heating system and a molten bed reactor (1); The electromagnetic induction heating system includes an electromagnetic induction heating coil (4), which is wrapped around the outer wall of the reactor cylinder and is used to pass in electrical energy and generate a high-frequency alternating magnetic field. The bed of the molten bed reactor (1) is filled with molten salt (2) and magnetic elements (3) mixed in a preset volume ratio. The inner wall of the molten bed reactor (1) is provided with a magnetic liner (8). The magnetic elements (3) and the magnetic liner (8) generate eddy current heating under the action of a high-frequency alternating magnetic field, heating the molten salt (2) to 800-1000℃ and melting it to form a high-temperature molten bed. The cylindrical wall of the molten bed reactor (1) consists of a corrosion-resistant high-temperature coating (9), a magnetic liner (8), an air film layer (7), a high-temperature alloy shell (6), and a heat insulation layer (5) from the inside out. The electromagnetic induction heating coil (4) is wrapped around the outer wall of the heat insulation layer (5). The upper part of the molten bed reactor (1) is provided with a feeding mechanism (10), and the upper side of the molten bed reactor (1) is provided with an outlet pipe (14). The two sides of the cylinder wall of the molten bed reactor (1) are respectively provided with a first ash overflow port (11) and a second ash overflow port (12). The coal powder is transported to the surface of the high temperature molten bed through the feeding mechanism (10) and reacts with the gasifying agent to generate syngas. The syngas is discharged through the outlet pipe (14), and the ash is discharged through the ash overflow port.

2. The molten bed coal gasification reactor based on induction heating according to claim 1, characterized in that, The corrosion-resistant high-temperature coating (9) is a high-temperature anti-corrosion, heat-conducting and energy-saving nano-coating that can withstand temperatures above 1300℃. The insulation layer (5) is a non-magnetic material.

3. The molten bed coal gasification reactor based on induction heating according to claim 1, characterized in that, The magnetic liner (8) is selected from one or more of high-purity graphite, silicon carbide, and graphite-silicon carbide composite materials; the magnetic element (3) is a spherical or rod-shaped magnetic heating metal material.

4. The molten bed coal gasification reactor based on induction heating according to claim 1, characterized in that, The molten salt (2) is a binary carbonate molten salt. The binary carbonate molten salt has the characteristics of good thermal stability, low viscosity, high heat capacity and large thermal conductivity at high temperature, and has a catalytic effect on gasification reaction.

5. The molten bed coal gasification reactor based on induction heating according to claim 1, characterized in that, The feeding mechanism (10) includes a screw feeder (15), an air inlet pipe (13), and a conveying pipe (16). The air inlet pipe (13) and the conveying pipe (16) adopt a sleeve structure. The conveying pipe (16) is located in the inner layer and has an opening on the bottom side wall. The air inlet pipe (13) is located in the outer layer and has a trumpet shape at the bottom. The screw feeder (15) adjusts the speed through a stepper motor controller, thereby controlling the coal powder addition flow rate. The carrier gas is introduced through the air inlet pipe (13). The trumpet-shaped structure at the bottom of the air inlet pipe (13) plays a role in blowing and dispersing the coal powder, so that the coal powder is evenly sprayed onto the surface of the high-temperature molten bed through multiple openings of the conveying pipe.

6. The molten bed coal gasification reactor based on induction heating according to claim 2, characterized in that, The gas film layer (7) can introduce cooling gas, which can reduce the temperature of the high-temperature alloy shell (6) to below 600°C without affecting the temperature stability of the high-temperature molten bed; the high-temperature alloy shell (6) can meet the high-temperature and high-pressure gasification requirements at 1000°C and 2MPa pressure.

7. The molten bed coal gasification reactor based on induction heating according to claim 5, characterized in that, It also includes a temperature closed-loop control system installed on the molten bed reactor (1) and electrically connected to the electromagnetic induction heating coil (4). The temperature closed-loop control system includes a contact thermocouple probe and a PLC control system. The contact thermocouple probe extends into the high-temperature molten bed to accurately measure the bed temperature and transmit the data to the PLC control system. The PLC control system compares the actual temperature with the preset target value and achieves dynamic and precise adjustment of the bed temperature by adjusting the output power of the electromagnetic induction heating coil (4).

8. The molten bed coal gasification reactor based on induction heating according to claim 7, characterized in that, A portion of the carrier gas can be replaced by a gasifying agent, and the replaced gasifying agent reacts with the coal powder on the surface of the high-temperature molten bed. The first ash overflow port (11) and the second ash overflow port (12) are discharged online. The discharge is achieved by stopping the feeding, closing the valve of the gas outlet pipe (14), and opening the valves of the first ash overflow port (11) and the second ash overflow port (12). During the discharge process, the temperature closed-loop control system adaptively adjusts the current of the electromagnetic induction heating coil (4) according to the bed temperature change to maintain the bed temperature stability.

9. A method for using molten bed coal gasification based on the apparatus according to any one of claims 1-8, characterized in that, Includes the following steps: S1. Start the electromagnetic induction heating system and use low-quality green electricity to drive the electromagnetic induction heating coil (4) to generate a high-frequency alternating magnetic field, so that the magnetic liner (8) and the magnetic element (3) are heated by eddy currents, and the molten salt (2) is heated and melted to form a high-temperature molten bed of 800℃-1000℃. S2. The bed temperature is stabilized at the preset target value through the temperature closed-loop control system. At the same time, cooling gas is introduced through the gas film layer (7) to keep the temperature of the high-temperature alloy shell (6) below 600°C and adjust the pressure inside the reactor to 2MPa. S3. Start the feeding mechanism (10), adjust the coal powder feeding amount through the screw feeder (15), and spray the coal powder evenly onto the surface of the high temperature molten bed under the action of the carrier gas. The coal powder reacts with the gasifying agent to generate syngas, and the syngas is discharged through the gas outlet pipe (14). S4. During the reaction process, when the ash and slag accumulate to the preset amount, online slag discharge operation is performed; after the slag discharge is completed, the valves of the first ash and slag overflow port (11) and the second ash and slag overflow port (12) are closed, the valve of the gas outlet pipe (14) is opened, the feeding is resumed, and the device is put into continuous operation.

10. The method of use according to claim 9, characterized in that, In S1, the electromagnetic induction heating system controls the heating energy input by adjusting the current of the electromagnetic induction heating coil (4). When the bed temperature is lower than the preset value, the current is increased, and when it is higher than the preset value, the current is decreased. In S3, a portion of the carrier gas can be replaced by a gasifying agent. The replacement ratio can be flexibly adjusted according to the gasification reaction requirements to optimize the synthesis gas yield and gas composition.

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