An internal heating type electromagnetic induction heating reinforced methane dry reforming fluidized bed reaction system

Abstract

The present application belongs to the technical field of methane dry reforming, and particularly relates to an internal heating type electromagnetic induction heating reinforced methane dry reforming fluidized bed reaction system. The system comprises a gas feeding unit, a reaction unit, an electromagnetic induction heating unit, a gas-liquid separation unit and a control unit. The gas source of methane and carbon dioxide is preheated by the gas feeding unit and then enters the reaction unit. The fluidized bed of the reaction unit is heated by the electromagnetic induction heating unit. The parameters of the electromagnetic induction heating unit are adjusted by the control unit during the reaction process. The reaction products are separated by the gas-liquid separation unit to obtain gas products and liquid products respectively. The internal heating type electromagnetic induction heating technology is used to replace the traditional external heating mode, and the fluidized bed is used to replace the fixed bed. The two modes are organically combined to solve the key problems of rapid heat transfer and carbon deposition suppression in the methane dry reforming process.

Description

Technical Field

[0001] This invention belongs to the field of methane dry reforming technology, specifically relating to an internally heated electromagnetic induction heating enhanced fluidized bed reaction system for methane dry reforming. Background Technology

[0002] Hydrogen energy, hailed as the energy of the "21st century," plays an increasingly important role on the world energy stage due to its high calorific value, excellent combustion performance, and pollution-free reaction products. With the exploitation and utilization of unconventional natural gas resources such as coalbed methane, shale gas, and methane hydrate, methane-to-hydrogen production will become an increasingly important method in my country. Among these methods, dry methane reforming is a highly promising thermochemical hydrogen production method. Its advantage lies in its ability to simultaneously utilize both CH4 and CO2, two major greenhouse gases, making it both environmentally friendly and economically valuable.

[0003] The dry reforming of methane for hydrogen production is characterized by high temperature and high energy consumption. Rapid heat transfer and precise control are often limiting factors for its reaction rate. To address this, patent specification CN111718737B discloses a reaction apparatus for the catalytic reforming of methane and carbon dioxide to produce syngas. The shell-side cavity of this apparatus houses multiple hexagonally arranged gas reaction tubes, each filled with a catalyst. A flame burner is connected to the outer surface of the shell-side cavity for heating. This traditional external heating method requires heat transfer from the reactor wall to the catalyst bed, resulting in low heat transfer efficiency, uneven heating distribution, complex equipment structure, and difficulty in precise temperature control of the reaction zone. More importantly, it easily creates a large temperature gradient between the reactor wall and the catalyst bed, leading to carbon buildup and deactivation on the catalyst surface, potentially causing blockage of the reaction tubes. Catalyst carbon buildup and deactivation have become a technical bottleneck restricting the industrial application of dry methane reforming. In contrast, electromagnetic induction heating technology can avoid the intermediate heat transfer medium in traditional heating, directly providing the required heat to the reaction zone, improving thermal efficiency, reducing the temperature gradient inside the reactor, and helping to suppress catalyst deactivation by carbon buildup.

[0004] The patent specification with publication number CN114558525B discloses a reaction apparatus for the catalytic synthesis of syngas from methane and carbon dioxide. It employs an electromagnetic induction heating coil to heat the reaction tube, and an inner liner is installed inside the gas reaction tube. The catalyst is stored within the jacket of the liner, increasing the contact area between the mixed gas and the catalyst, thereby improving the catalytic synthesis efficiency. However, this patent uses a fixed-bed reactor and simple heating of the reaction tube wall. The single heating surface often leads to poor heat and mass transfer, low gas-solid contact rate, large bed temperature gradient, low energy utilization, and catalyst carbon buildup clogging the channels, severely impacting the catalytic reforming efficiency. In contrast, fluidized beds offer advantages such as uniform particle mixing, high heat and mass transfer efficiency, and sufficient gas-solid contact. Their excellent heat transfer characteristics and intense particle collisions effectively suppress carbon buildup on the catalyst surface, thereby enhancing operational stability and effectively reducing catalyst regeneration difficulty. However, fluidization is susceptible to various factors, potentially leading to non-fluidization and weakened gas-solid contact. Introducing a magnetic field to suppress backmixing and bubble formation further improves gas-solid contact efficiency and reduces catalyst carbon buildup. Therefore, electromagnetic induction heating fluidized bed reaction systems are expected to become an important technical means to solve the heat transfer limitations and carbon deposition in methane dry reforming and realize its industrial application. Summary of the Invention

[0005] To address the technical problems of uneven heating, difficulty in temperature control, and catalyst deactivation due to coking in existing methane dry reforming reaction systems, this invention adopts internal heating electromagnetic induction heating technology to replace the traditional external heating method and uses a magnetic fluidized bed to replace the fixed bed. The two methods are organically combined to solve the key problems of rapid heat transfer and inhibition of coking in the methane dry reforming process.

[0006] This invention directly provides the required heat to the reaction zone through electromagnetic induction heating, which not only greatly improves heat transfer efficiency but also reduces the temperature gradient distribution inside the reactor, thereby effectively suppressing the formation of carbon deposits on the catalyst surface. Secondly, the use of a magnetic-catalytic bifunctional porous particulate catalyst (such as the magnesium-iron spinel magnetic catalyst for coal catalytic pyrolysis disclosed in CN 113559876 B) enables precise temperature control of the reaction zone, avoiding hot spots and local overheating, and ensuring the high efficiency and stability of the catalyst. The application of a fluidized bed reactor under the action of a magnetic field also ensures sufficient contact between the reactant gas and the catalyst. Finally, a heat recovery device is installed at the reactor outlet and the induction coil section to recover the heat from the separation of condensed gas-liquid reactants and the cooling of the coil, thereby improving energy utilization efficiency. The organic combination of the above technologies realizes a complete internally heated electromagnetic induction-enhanced methane dry reforming fluidized bed reaction system, which can operate sustainably and stably, breaking through the industrialization technology bottleneck in this field.

[0007] This invention provides an internally heated electromagnetic induction heating enhanced methane dry reforming fluidized bed reaction system, comprising a gas feeding unit, a reaction unit, an electromagnetic induction heating unit, a gas-liquid separation unit, and a control unit.

[0008] The gas feeding unit includes a preheater. The reaction unit includes a fluidized bed reactor and a magnetic-catalytic bifunctional catalyst. The electromagnetic induction heating unit includes a high-frequency induction heater and an induction coil. The gas-liquid separation unit includes a chiller, a condenser, and a separator. The control unit includes a temperature sensor, a pressure sensor, and a flow sensor; Methane and carbon dioxide gas sources are preheated by the gas feed unit before entering the reaction unit. The fluidized bed reactor in the reaction unit is heated and reacted by an electromagnetic induction heating unit. During the reaction, the parameters of the electromagnetic induction heating unit are adjusted by a control unit. The reaction products are separated into gaseous and liquid products by a gas-liquid separation unit. The cooperation of the above units realizes an internally heated electromagnetic induction heating enhanced fluidized bed reaction system for methane dry reforming.

[0009] Furthermore, the gas sources of methane and carbon dioxide are connected to the gas inlet end of the preheater, the gas outlet end of the preheater is connected to the inlet end of the fluidized bed reactor, the outlet end of the fluidized bed reactor is connected to the inlet end of the condenser, the outlet end of the condenser is connected to the inlet end of the separator, and the upper part of the separator is provided with a gas outlet and the lower part with a liquid outlet.

[0010] Furthermore, the fluidized bed reactor is also filled with a magnetic-catalytic bifunctional catalyst, which has the ability to catalyze the dry reforming reaction of methane and the ability to respond to electromagnetic induction heating, and can regulate particle movement under the action of the magnetic field of a high-frequency induction coil.

[0011] Furthermore, the fluidized bed reactor is surrounded by an electromagnetic induction coil, which is connected to a high-frequency induction heater. The outlet of the high-frequency induction heater is connected to the condensate inlet of the condenser. The inlet of the high-frequency induction heater is connected to the liquid outlet of the preheater via a chiller, and the condensate outlet of the condenser is connected to the liquid inlet of the preheater.

[0012] Furthermore, a temperature sensor is installed in the lower middle part of the fluidized bed reactor, a pressure sensor is installed in the upper part of the fluidized bed reactor, and a flow sensor is installed on the circulating water pipe between the high-frequency induction heater and the condenser.

[0013] In this invention, The preheater is used to mix and preheat the methane and carbon dioxide feedstock gases to the required reaction temperature.

[0014] Fluidized bed reactors are used for methane dry reforming to produce hydrogen. The outer walls are covered with insulating material to reduce heat loss.

[0015] A high-frequency induction heater is used to convert 50Hz low-frequency electricity into 20kHz high-frequency alternating current, which is then output to the induction coil to enhance eddy currents and the skin effect, thereby improving heating intensity and efficiency. The induction coil is a multi-turn spiral coil wound around the outside of the fluidized bed reactor, forming an alternating magnetic field inside the reactor. Under the induction effect of the alternating magnetic field, electrical energy is converted into magnetic energy using the principle of electromagnetic induction, and then transferred to the magnetic-catalyst bifunctional catalyst inside the fluidized bed reactor, thus achieving direct internal heating of the magnetic-catalyst bifunctional catalyst.

[0016] The condensate in the condenser comes from a chiller shared with the electromagnetic induction heating unit, and is used to cool the liquid and recover heat.

[0017] The separator is used to separate the gas-liquid mixture from the condenser into gas and water. A valve is located below the separator to remove water during the reaction process.

[0018] Temperature, pressure, and flow sensors are used to monitor and collect temperature, pressure, and flow parameters during the reaction process, respectively. Based on the set reaction conditions and parameter signals, they are used to adjust and control the high-frequency induction heater to ensure that the reaction temperature and reaction conditions are maintained.

[0019] In this invention, the preheater, the high-frequency induction heater, and the condenser also constitute a heat recovery unit. The preheater is set after the high-frequency induction heater and the condenser to recover the waste heat generated by the high-frequency induction heater and transport it to the preheater for preheating the raw material gas, thereby realizing heat recovery and improving energy utilization efficiency.

[0020] The beneficial effects of this invention are: (1) The heat transfer efficiency is significantly improved, the temperature distribution inside the fluidized bed reactor is uniform, and the carbon buildup on the catalyst surface is effectively suppressed, solving the problems of low efficiency and carbon buildup in traditional external heating. Compared with traditional external heating, electromagnetic induction heating efficiency can be improved by more than 10%.

[0021] (2) The interaction between the fluidized bed reactor and the magnetic-catalytic bifunctional catalyst particles significantly improves the gas-solid contact efficiency and enhances the gas-solid mass transfer conditions. Introducing a magnetic field can reduce the minimum fluidization velocity, decrease the bubble content, and suppress backmixing.

[0022] (3) The present invention provides the required heat to the reaction zone directly through electromagnetic induction heating, which not only greatly improves the heat transfer efficiency, but also reduces the temperature gradient distribution inside the reactor, thereby effectively suppressing the generation of carbon deposits on the catalyst surface.

[0023] (4) The use of magnetic-catalytic dual-function porous particles makes the temperature of the reaction zone precisely controllable, and the temperature fluctuation is controlled within ±5°C to avoid local overheating.

[0024] (5) The reaction stability and continuous running time are significantly improved.

[0025] (6) The heat recovery process improves the system's energy efficiency by about 10%.

[0026] (7) This technical route has successfully overcome the industrialization technical difficulties of the dry reforming process of methane, and realized a continuous hydrogen production process with high thermal efficiency, less coking, and stable reaction, which has important engineering application prospects. Attached Figure Description

[0027] Figure 1 Schematic diagram of a fluidized bed reaction system for enhanced methane dry reforming using internal heating electromagnetic induction heating. Explanation of reference numerals in the attached figures: 1-Preheater; 2-Chiller; 3-High-frequency induction heater; 4-Induction coil; 5-Magnetic-catalytic bifunctional catalyst; 6-Fluidized bed reactor; 7-Condenser; 8-Separator; 9-Temperature sensor; 10-Pressure sensor; 11-Flow sensor. Detailed Implementation

[0028] The present invention discloses an internally heated electromagnetic induction heating enhanced fluidized bed reaction system for methane dry reforming, the structure of which is as follows: Figure 1 As shown.

[0029] The system includes a gas feeding unit, a reaction unit, an electromagnetic induction heating unit, a gas-liquid separation unit, and a control unit; the cooperation of these units realizes an internally heated electromagnetic induction heating enhanced methane dry reforming fluidized bed reaction system.

[0030] The gas feeding unit includes a preheater 1. The reaction unit includes a fluidized bed reactor 6 and a magnetic-catalytic bifunctional catalyst 5. The electromagnetic induction heating unit includes a high-frequency induction heater 3 and an induction coil 4. The gas-liquid separation unit includes a chiller 2, a condenser 7, and a separator 8. The control unit includes a temperature sensor 9, a pressure sensor 10, and a flow sensor 11; The gas sources for methane and carbon dioxide are connected to the gas inlet of the preheater 1 in the feeding unit. The gas outlet of the preheater 1 is connected to the inlet of the fluidized bed reactor 6. The outlet of the fluidized bed reactor 6 is connected to the inlet of the condenser 7. The outlet of the condenser 7 is connected to the inlet of the separator 8. The separator 8 has a gas outlet at the top and a liquid outlet at the bottom. The fluidized bed reactor 6 is also filled with a magnetic-catalytic bifunctional catalyst 5. The magnetic-catalytic bifunctional catalyst 5 has both the ability to catalyze the dry reforming reaction of methane and the ability to respond to electromagnetic induction heating. It also regulates particle movement under the magnetic field of the high-frequency induction coil. The fluidized bed reactor 6 is surrounded by an electromagnetic induction coil 4. The induction coil 4 is connected to a high-frequency induction heater 3. The outlet of the high-frequency induction heater 3 is connected to the condensate inlet of the condenser 7. The inlet of the high-frequency induction heater 3 is connected to the liquid outlet of the preheater 1 through a chiller 2. The condensate outlet of the condenser 7 is connected to the liquid inlet of the preheater 1.

[0031] A temperature sensor 9 is installed in the lower middle part of the fluidized bed reactor 6, a pressure sensor 10 is installed in the upper part of the fluidized bed reactor 6, and a flow sensor 11 is installed on the circulating water pipe between the high-frequency induction heater 3 and the condenser 7. Temperature, pressure, and flow parameters during the reaction process are monitored and collected, and the high-frequency induction heater 3 and other components are adjusted and controlled according to the set reaction conditions and parameter signals to ensure that the reaction temperature and reaction conditions are maintained.

[0032] Fluidized bed reactor 6 is used for methane dry reforming to produce hydrogen. Its outer wall is covered with heat insulation material to reduce heat loss.

[0033] The condensate in condenser 7 comes from chiller 2, which is shared with the electromagnetic induction heating unit, and is used to cool the liquid and recover heat.

[0034] Separator 8 is used to separate the gas-liquid mixture from condenser 7 into gas and water. A valve is provided below separator 8 to remove water during the reaction process.

[0035] The high-frequency induction heater 3 is used to convert 50Hz low-frequency electricity into 20KHz high-frequency alternating current and output it to the induction coil 4. The induction coil 4 is a multi-turn spiral coil that is wrapped around the outside of the fluidized bed reactor 6. Using the principle of electromagnetic induction, it converts magnetic energy into heat energy and transfers it to the magnetic-catalytic bifunctional catalyst 5 inside the fluidized bed reactor 6, thereby achieving direct internal heating of the catalyst 5.

[0036] In this invention, the preheater 1, the high-frequency induction heater 3, and the condenser 7 also constitute a heat recovery unit. The preheater 1 is set after the high-frequency induction heater 3 and the condenser 7 to recover the waste heat generated by the high-frequency induction heater 3 and transport it to the preheater 1 for preheating the raw material gas, thereby realizing heat recovery and improving energy utilization efficiency.

[0037] This invention discloses an internally heated electromagnetic induction heating enhanced fluidized bed reaction system for methane dry reforming. By employing a magnetic-catalytic bifunctional catalyst and electromagnetic induction heating technology, it achieves internal heating of the fluidized bed reactor, increasing the reaction temperature and rate while reducing the energy consumption and equipment complexity of external heating. The system also incorporates a heat recovery unit to recover heat generated during the reaction, further improving energy utilization efficiency. This system features simple structure, convenient operation, high reaction efficiency, and low energy consumption, making it suitable for the industrial production of hydrogen from methane dry reforming.

Claims

1. A fluidized bed reaction system for enhanced methane dry reforming using internally heated electromagnetic induction heating, characterized in that, It includes a gas feeding unit, a reaction unit, an electromagnetic induction heating unit, a gas-liquid separation unit, and a control unit; The gas feeding unit includes a preheater (1). The reaction unit includes a fluidized bed reactor (6) and a magnetic-catalytic bifunctional catalyst (5). The electromagnetic induction heating unit includes a high-frequency induction heater (3) and an induction coil (4). The gas-liquid separation unit includes a chiller (2), a condenser (7), and a separator (8). The control unit includes a temperature sensor (9), a pressure sensor (10), and a flow sensor (11). After the gas sources of methane and carbon dioxide are preheated by the gas feed unit, they enter the reaction unit. The fluidized bed reactor (6) of the reaction unit is heated and reacted by the electromagnetic induction heating unit. During the reaction, the parameters of the electromagnetic induction heating unit are adjusted by the control unit. The reaction products are separated by the gas-liquid separation unit to obtain gaseous products and liquid products respectively.

2. The internally heated electromagnetic induction heating enhanced methane dry reforming fluidized bed reaction system as described in claim 1, characterized in that, The gas sources of methane and carbon dioxide are connected to the gas inlet end of the preheater (1), the gas outlet end of the preheater (1) is connected to the inlet end of the fluidized bed reactor (6), the outlet end of the fluidized bed reactor (6) is connected to the inlet end of the condenser (7), the outlet end of the condenser (7) is connected to the inlet end of the separator (8), and the upper part of the separator (8) is provided with a gas outlet and the lower part is provided with a liquid outlet.

3. The internally heated electromagnetic induction heating enhanced methane dry reforming fluidized bed reaction system as described in claim 1, characterized in that, The fluidized bed reactor (6) is also filled with a magnetic-catalytic bifunctional catalyst (5), which has the ability to catalyze the dry reforming reaction of methane and the ability to respond to electromagnetic induction heating, and implements particle motion regulation under the action of the magnetic field of the high-frequency induction coil.

4. The internally heated electromagnetic induction heating enhanced methane dry reforming fluidized bed reaction system as described in claim 1, characterized in that, The fluidized bed reactor (6) is surrounded by an electromagnetic induction coil (4), which is connected to a high-frequency induction heater (3). At the same time, the outlet of the high-frequency induction heater (3) is connected to the condensate inlet of the condenser (7). The inlet of the high-frequency induction heater (3) is connected to the liquid outlet of the preheater (1) through a chiller (2), and the condensate outlet of the condenser (7) is connected to the liquid inlet of the preheater (1).

5. The internally heated electromagnetic induction heating enhanced methane dry reforming fluidized bed reaction system as described in claim 1, characterized in that, A temperature sensor (9) is installed in the lower middle part of the fluidized bed reactor (6), a pressure sensor (10) is installed in the upper part of the fluidized bed reactor (6), and a flow sensor (11) is installed on the circulating water pipe between the high-frequency induction heater (3) and the condenser (7).

6. The internally heated electromagnetic induction heating enhanced methane dry reforming fluidized bed reaction system as described in claim 1, characterized in that, The outer wall of the fluidized bed reactor (6) is covered with heat insulation material.

7. The internally heated electromagnetic induction heating enhanced methane dry reforming fluidized bed reaction system as described in claim 1, characterized in that, The high-frequency induction heater (3) is used to convert 50Hz low-frequency electricity into 20KHz high-frequency alternating current and output it to the induction coil (4). The induction coil (4) is a multi-turn spiral coil that surrounds the outside of the fluidized bed reactor (6) and forms an alternating magnetic field inside the fluidized bed reactor (6). Under the induction of the alternating magnetic field, the magnetic energy is converted into heat energy and transferred to the magnetic-catalytic bifunctional catalyst (5) inside the fluidized bed reactor (6), thereby realizing direct internal heating of the magnetic-catalytic bifunctional catalyst (5).

8. The internally heated electromagnetic induction heating enhanced methane dry reforming fluidized bed reaction system as described in claim 1, characterized in that, Temperature sensor (9), pressure sensor (10) and flow sensor (11) are used to monitor and collect temperature, pressure and flow parameters during the reaction process, respectively, and adjust and control the high-frequency induction heater (3) according to the set reaction conditions and parameter signals.

9. The internally heated electromagnetic induction heating enhanced methane dry reforming fluidized bed reaction system as described in claim 1, characterized in that, The preheater (1), the high-frequency induction heater (3) and the condenser (7) also constitute a heat recovery unit. The preheater (1) is set after the high-frequency induction heater (3) and the condenser (7) to recover the waste heat generated by the high-frequency induction heater (3) and transport it to the preheater (1).

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