Plasma high-temperature melting device and automatic discharging method

Abstract

The application discloses a kind of plasma high temperature melting device and automatic discharging method, including plasma high temperature pyrolysis melting furnace, plasma torch is arranged on plasma high temperature pyrolysis melting furnace, infrared temperature monitoring device, molybdenum electrode auxiliary heating device, discharging mechanism device and control transmission device;Infrared temperature monitoring device is used to carry out real-time monitoring to the temperature of molten glass in plasma high temperature pyrolysis melting furnace;Molybdenum electrode auxiliary heating device is used to assist heating to molten glass;Control transmission device is used to carry out motion control to molybdenum electrode auxiliary heating device and discharging mechanism device.The plasma high temperature melting device and automatic discharging method provided in the application can effectively solve the problem of large temperature gradient of molten pool, improve the uniformity of molten pool temperature, and then improve the fluidity of glass body, promote the discharging process, and prevent the blockage accident caused by glass condensation at the discharging port.

Description

Technical Field

[0001] This application belongs to the field of radioactive waste treatment technology, and more specifically, relates to a plasma high-temperature melting device and an automatic discharge method. Background Technology

[0002] With the rapid development of the nuclear industry, nuclear power plants generate a large amount of radioactive waste that needs to be properly disposed of to ensure environmental safety. How to economically and effectively treat radioactive waste is a pressing issue worldwide. In my country, the common solid radioactive waste treatment process is cement solidification technology, which has the disadvantage of excessively high volume expansion ratios and a severe shortage of low-level waste disposal sites and temporary storage facilities. High-temperature plasma melting technology provides a new approach to radioactive waste disposal—minimization, stabilization, and inorganicization. High-temperature plasma melting generally includes two main processes: pyrolysis of organic matter and melting of inorganic matter. Waste enters the high-temperature zone generated by plasma and undergoes pyrolysis, generating combustible small molecules that then react with oxygen. Inorganic matter is melted to form stable vitreous material, and the vitreous residue is collected into specific containers through a preparation system.

[0003] In existing technologies, because plasma high-temperature melting furnaces use plasma torches as the heat source, a temperature gradient exists within the molten glass pool, resulting in uneven overall temperature distribution. The molten glass exhibits high viscosity and poor fluidity during discharge, making it highly susceptible to blockage at the discharge port due to glass condensation. This prevents the smooth discharge of glass residue from the furnace, ultimately leading to furnace shutdown for maintenance. Successful discharge of the glass signifies successful waste volume reduction. Therefore, ensuring the smooth discharge of glass residue from the plasma melting furnace is one of the key aspects of plasma high-temperature melting technology. Summary of the Invention

[0004] To achieve the above objectives, the technical solution adopted in this application is as follows: a plasma high-temperature melting device is provided, comprising: a plasma high-temperature pyrolysis melting furnace, wherein the plasma high-temperature pyrolysis melting furnace is equipped with a plasma torch, an infrared temperature monitoring device, a molybdenum electrode auxiliary heating device, a discharge mechanism device, and a control and transmission device; the infrared temperature monitoring device is used to monitor the temperature of the molten glass in the plasma high-temperature pyrolysis melting furnace in real time; the molybdenum electrode auxiliary heating device is used to provide auxiliary heating for the molten glass; and the control and transmission device is used to control the motion of the molybdenum electrode auxiliary heating device and the discharge mechanism device.

[0005] Optionally, the plasma high-temperature pyrolysis melting furnace is L-shaped, including a vertically arranged vertical furnace section chamber and a horizontally arranged melting section chamber. The vertical furnace section chamber includes a waste preheating and drying section, a waste pyrolysis gasification section, and an oxidation section connected sequentially from top to bottom. The melting section chamber is located below the oxidation section.

[0006] Optionally, the sidewalls of the vertical furnace section chamber and the melting section chamber include, from the inside out, a high-chromium electromolten material, a crack-resistant sealing material, a mullite lightweight insulating brick, a zirconium-containing aluminum silicate fiber board, a nano-insulation board, and a metal shell.

[0007] Optionally, the plasma torch is installed at the top of the melting section chamber with a horizontal tilt angle of 45° downwards; and / or, the plasma torch is a non-transfer DC plasma torch, the gas medium is nitrogen, and the plasma torch is connected to a plasma torch power supply; and / or, the infrared temperature monitoring device includes multiple infrared temperature monitors, which are grouped in pairs, with two infrared temperature monitors in each group symmetrically arranged on the side of the melting section chamber; and / or, the infrared temperature monitoring device is installed with a vertical tilt angle of 45° downwards.

[0008] Optionally, the molybdenum electrode auxiliary heating device includes multiple molybdenum electrode groups, each of which includes two molybdenum electrodes symmetrically arranged on the side of the molten section chamber. The molybdenum electrodes can be inserted into the molten pool to heat the glass melt, and each molybdenum electrode group is powered by an independent DC power supply.

[0009] Optionally, the molybdenum electrode auxiliary heating device further includes a first cooling water jacket, a first fixed flange, and a first protective gas inlet pipe. The molybdenum electrode is threadedly connected to the first cooling water jacket. The first cooling water jacket is installed on the side of the melting section chamber through the first fixed flange. The molybdenum electrode is installed at a horizontal angle of 45° downwards. The first protective gas inlet pipe is fixed on both sides of the first cooling water jacket and is used to introduce nitrogen gas to protect the molybdenum electrode.

[0010] Optionally, the discharge mechanism includes a tungsten rod, a second cooling water jacket, a second fixed flange, a second protective gas inlet pipe, and an induction heating coil; the tungsten rod is threadedly connected to the second cooling water jacket, the second cooling water jacket is fixed to the side of the melting section chamber through the second fixed flange, the second protective gas inlet pipe is provided on both sides of the second cooling water jacket for introducing nitrogen gas to protect the tungsten rod, the induction heating coil is sleeved on the tungsten rod for induction heating of the tungsten rod, and the induction heating coil is connected to a high-frequency induction heating power supply.

[0011] Optionally, the longitudinal distance between the tungsten rod and the bottom of the molten section chamber is not less than 50 mm; and / or, the distance between the end of the molybdenum electrode and the bottom of the molten section chamber is greater than the distance between the tungsten rod and the bottom of the molten section chamber.

[0012] Optionally, the number of control transmission devices is multiple, and each control transmission device includes a motor, a reducer, a driving gear and a driven gear connected in sequence. The rotation center of the driven gear is threadedly connected to the water jacket of the corresponding molybdenum electrode or tungsten rod; and / or, the speed at which the tungsten rod moves into or out of the furnace is 100 mm / min; and / or, the speed at which the molybdenum electrode moves into or out of the furnace is 200 mm / min.

[0013] On the other hand, this application also provides an automatic discharge method for a plasma high-temperature melting device, employing the apparatus provided in the first aspect, comprising:

[0014] S1: Initialize the discharge system; ensure that the molybdenum electrodes are all in the deactivated state, the tungsten rod is in the off state, and the plasma torch is in the running state;

[0015] S2: Determine whether the plasma torch is turned on; if not, return to step S1; if yes, proceed to step S3.

[0016] S3: Determine whether the temperatures monitored by a group of infrared temperature monitors near the discharge mechanism are all greater than 800℃; if not, perform a no-load operation; if yes, proceed to step S4.

[0017] S4: Drive the molybdenum electrode assembly near the discharge mechanism to move into the furnace at a speed of 200 mm / min, and stop after reaching the limit.

[0018] S5: Set the heating power of the molybdenum electrode group near the discharge mechanism to 3-5kW;

[0019] S6: Shut down the plasma torch;

[0020] S7: Determine whether the temperatures monitored by the group of infrared temperature monitors located in the middle are all greater than 800℃; if not, perform a no-operation; if yes, proceed to step S8;

[0021] S8: Drives the molybdenum electrode group located in the middle to move into the furnace at a speed of 200 mm / min, and stops after reaching the limit.

[0022] S9: Set the heating power of the molybdenum electrode group located in the middle to 5-7kW;

[0023] S10: Determine whether the temperatures monitored by a group of infrared temperature monitors located away from the discharge mechanism are all greater than 800°C; if not, perform a no-load operation; if yes, proceed to step S11.

[0024] S11: Drive the molybdenum electrode assembly, which is away from the discharge mechanism, into the furnace at a speed of 200 mm / min, and stop after reaching the limit.

[0025] S12: Set the heating power of the molybdenum electrode group located away from the discharge mechanism to 7-9 kW;

[0026] S13: Determine if all infrared temperature monitors are above 1100℃; if not, perform a no-operation; if yes, proceed to step S14.

[0027] S14: Start the induction heating coil, the power of which is 15-25kW;

[0028] S15: Start the control motor of the tungsten rod, causing it to move out of the furnace at a speed of 100 mm / min and stop after reaching the limit.

[0029] S16: Determine whether the material discharge is complete; if the power output of all molybdenum electrodes is not 0, perform a no-operation and proceed to step S16; if all are 0, proceed to step S17.

[0030] S17: Start the control motor of the tungsten rod, so that it moves into the furnace at a speed of 100 mm / min and stops after reaching the limit.

[0031] S18: Turn off the power to the induction heating coil;

[0032] S19: Drive all molybdenum electrodes to move outward from the furnace at a speed of 200 mm / min. Stop when they reach the limit, turn off the power supply to all molybdenum electrodes, and complete the discharge.

[0033] The beneficial effects of the plasma high-temperature melting device provided in this application are as follows: Compared with the prior art, the plasma high-temperature melting device provided in this application solves the problem of large temperature gradient in the molten pool by using molybdenum electrode heating, improves the temperature uniformity of the molten pool, thereby improving the fluidity of the glass, promoting the discharge process, and preventing accidents caused by glass condensation at the discharge port; the temperature of the molten glass is monitored in real time by an infrared temperature monitoring device and fed back to the control and transmission device, which controls the movement of the discharge mechanism and the molybdenum electrode auxiliary heating device, realizing fully automated control of the discharge process, which can significantly improve the overall stability and safety of the plasma melting furnace system, and greatly improve the service life of the system and waste treatment efficiency.

[0034] The beneficial effects of the automatic material discharge method provided in this application are as follows: compared with the prior art, its superiority lies in the fact that the movement of the actuator can be driven in real time through the feedback of the infrared temperature sensor, which can accurately locate the initial conditions for material discharge and execute the material discharge process, and greatly improve the reliability of the system in the material discharge process. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the structure of the plasma high-temperature melting device provided in the embodiments of this application;

[0037] Figure 2 A schematic diagram of the structure of the molybdenum electrode auxiliary heating device in the plasma high-temperature melting apparatus provided in this application embodiment;

[0038] Figure 3 This is a schematic diagram of the discharge mechanism of the plasma high-temperature melting device provided in the embodiments of this application;

[0039] Figure 4 A schematic diagram of the control and transmission device of the plasma high-temperature melting apparatus provided in the embodiments of this application;

[0040] Figure 5 A flowchart of the discharge method provided in the embodiments of this application;

[0041] Figure 6 This is a cross-sectional view of the sidewalls of the vertical furnace section chamber and the melting section chamber in an embodiment of this application.

[0042] The following are the labeling elements in the figure:

[0043] 1-Plasma high-temperature pyrolysis melting furnace; 11-Vertical furnace section chamber; 12-Melting section chamber; 2-Plasma torch; 3-Infrared temperature monitoring device; 31-First temperature monitoring group; 32-Second temperature monitoring group; 33-Third temperature monitoring group; 4-Molybdenum electrode auxiliary heating device; 401-First fixed flange; 402-First cooling water jacket; 403-First protective gas inlet pipe; 404-Molybdenum electrode; 5-Discharge mechanism device; 51-Tungsten rod; 52-Second cooling water jacket; 53-Second fixed flange; 54-Second protective gas inlet pipe; 55-Induction heating coil; 6-Control and transmission device; 61-Driven gear; 62-Drive gear; 63-Reducer; 64-Motor. Detailed Implementation

[0044] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0045] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0046] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0047] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0048] Please refer to the following: Figure 1 and Figure 2 The plasma high-temperature melting apparatus provided in this application embodiment will now be described. The plasma high-temperature melting apparatus includes: a plasma high-temperature pyrolysis melting furnace 1, on which a plasma torch 2, an infrared temperature monitoring device 3, a molybdenum electrode auxiliary heating device 4, a discharge mechanism device 5, and a control and transmission device 6 are installed; the infrared temperature monitoring device 3 is used to monitor the temperature of the molten glass inside the plasma high-temperature pyrolysis melting furnace 1 in real time; the molybdenum electrode auxiliary heating device 4 is used to provide auxiliary heating for the molten glass; the infrared temperature monitoring device 3 is electrically connected to the control and transmission device 6 and is used to control the movement of the molybdenum electrode auxiliary heating device 4 and the discharge mechanism device 5.

[0049] The plasma high-temperature melting device provided in this application solves the problem of large temperature gradient in the molten pool by using molybdenum electrode heating, thereby improving the temperature uniformity of the molten pool, enhancing the fluidity of the glass, promoting the discharge process, and preventing blockages at the discharge port due to glass condensation. The plasma torch possesses characteristics of high temperature, high enthalpy, and high energy density, making it suitable for treating difficult-to-treat or specially treated pollutants, such as radioactive waste, and offering rapid processing. Compared to traditional incineration methods, it has lower exhaust emissions, making it more environmentally friendly and energy-efficient. Real-time monitoring of the molten glass temperature using an infrared temperature monitoring device and feedback to the control and transmission device enables motion control of the discharge mechanism and molybdenum electrode auxiliary heating device, achieving fully automated control of the discharge process. This significantly improves the overall stability and safety of the plasma melting furnace system, greatly extending its service life and waste treatment efficiency.

[0050] Please see Figure 1 In some embodiments of this application, the plasma high-temperature pyrolysis melting furnace 1 is L-shaped, including a vertically arranged vertical furnace section chamber 11 and a horizontally arranged melting section chamber 12. The vertical furnace section chamber 11 includes a waste preheating and drying section, a waste pyrolysis and gasification section, and an oxidation section connected sequentially from top to bottom. The melting section chamber 12 is located below the oxidation section. After the waste bag falls into the molten pool, the organic matter is decomposed to form combustible small molecules, and the inorganic matter descends to the bottom of the melting furnace and enters the molten pool together with the glass forming agent. After high-temperature melting, it forms a glassy slag.

[0051] In some embodiments of this application, the glass forming agent may be borosilicate glass with the following composition: SiO2 (50-60 wt.%), B2O3 (10-50 wt.%), CaO (10-15 wt.%), Al2O3 (5-10 wt.%), TiO2 (2-5 wt.%), and Na2O (10-15 wt.%). In other embodiments of this application, other commercially available glass forming agents may also be used, and this application does not limit the choice.

[0052] The advantage of using an L-shaped plasma high-temperature pyrolysis melting furnace lies in the bottom melting section chamber 12, where high-temperature gas and waste undergo a counter-current heat transfer process, providing heat to the waste for pyrolysis and drying. The partially gasified waste and inorganic ash descend to the oxidation section, where residual carbon reacts with the supplied air in an oxygen-deficient combustion process. The resulting combustible material is then introduced into the secondary combustion chamber for complete combustion.

[0053] In some embodiments of this application, the sidewalls of the vertical shaft furnace chamber 11 and the melting chamber 12 include, from the inside out (fire surface to outer shell), a high-chromium electrofused material (thickness 200-250 mm), a crack-resistant sealing material (thickness 40-80 mm), a mullite lightweight insulating brick (thickness 85-115 mm), a zirconium-containing aluminosilicate fiberboard (thickness 100-120 mm), and a nano-insulation board (thickness 30-50 mm). Figure 6 As shown in the diagram. This structural design effectively ensures that the temperature of the fire surface (1400℃) is reduced to 50℃ when transferred to the metal casing, thus lowering the risk of burns to operators. The fire surface uses a high-chromium electrofused material, which effectively prevents glass corrosion.

[0054] In other embodiments of this application, the sidewalls of the vertical furnace section chamber 11 and the melting section chamber 12 may also adopt other forms of refractory structure, which are not limited in this application.

[0055] Please see Figure 1 In some embodiments of this application, the plasma torch 2 is installed on top of the melting section chamber 12 with an installation tilt angle of 45° downwards.

[0056] Installing the plasma torch 2 at a 45° downward tilt angle increases the contact area between the flame of the plasma torch 2 and the waste pack, thereby improving the waste pyrolysis efficiency.

[0057] In some embodiments of this application, the plasma torch 2 is a non-transfer DC plasma torch, the gas medium is nitrogen, and the plasma torch 2 is connected to a plasma torch power supply.

[0058] In some embodiments of this application, the plasma torch 2 may be a non-transfer DC plasma torch, model WPT-150, manufactured by CNNC Tongchuang (Chengdu) Technology Co., Ltd. The plasma torch power supply may be an AT-150 medium-frequency inverter switching power supply manufactured by CNNC Tongchuang (Chengdu) Technology Co., Ltd., with RS485 communication control.

[0059] In some embodiments of this application, the infrared temperature monitoring device 3 includes multiple infrared temperature monitors, which are arranged in pairs, and the two infrared temperature monitors in each pair are symmetrically arranged on the side of the melting section chamber 12.

[0060] Please see Figure 1 In some embodiments of this application, the infrared temperature monitoring device 3 includes three temperature monitoring groups, which are sequentially the first temperature monitoring group 31, the second temperature monitoring group 32 and the third temperature monitoring group 33 in the direction away from the discharge mechanism device 5. Each temperature monitoring group includes two infrared temperature monitors.

[0061] Using six infrared temperature monitors installed on the side of the molten section chamber, the temperature of the molten pool can be directly monitored in real time, providing a basis for judgment in the subsequent discharge process. The six temperature measuring points are equivalent to six points evenly distributed on the surface of the molten pool, which can better judge the overall temperature uniformity of the molten pool.

[0062] In some other embodiments of this application, the number of temperature monitoring groups can also be set to multiple, such as 4 groups, 5 groups, etc., and this application does not limit it.

[0063] In some embodiments of this application, the infrared temperature monitor may be an Endurance infrared thermometer provided by Fluke Process Instruments, with a maximum range of 2000°C and RS485 communication control.

[0064] In some embodiments of this application, the infrared temperature monitor is mounted at a vertical tilt angle of 45° downwards.

[0065] In some embodiments of this application, the molybdenum electrode auxiliary heating device 4 includes multiple molybdenum electrode groups, each molybdenum electrode group including two molybdenum electrodes 404 symmetrically arranged on the side of the molten section chamber 12. The molybdenum electrodes 404 can be inserted into the molten pool to heat the glass melt, and each molybdenum electrode group is powered by an independent DC power supply.

[0066] In some embodiments of this application, the DC power supply is adjustable, and the maximum power of each group of molybdenum electrodes is 10kW.

[0067] In some embodiments of this application, the DC power supply for heating the molybdenum electrode can be a commercially available DC power source with a maximum output current of 150A and RS485 communication control.

[0068] The multiple 404 molybdenum electrodes are paired to form multiple heating circuits, which can significantly improve the uniformity of the temperature distribution in the molten pool. Each set of molybdenum electrodes uses an independent DC power supply unit, enabling rapid heat transfer using the Joule heat generated by the molten glass itself. This ensures a uniform temperature distribution in the molten pool and prevents the formation of "cold zones" in the molten glass far from the plasma torch area, thus avoiding obstacles in the discharge process.

[0069] In some embodiments of this application, the diameter of the molybdenum electrode can be selected as 40-50 mm. In other embodiments of this application, the diameter of the molybdenum electrode can also be other specifications, and this application does not limit it.

[0070] See Figure 1 In some embodiments of this application, the molybdenum electrode auxiliary heating device 4 includes three molybdenum electrode groups, which are sequentially the first molybdenum electrode group 41, the second molybdenum electrode group 42, and the third molybdenum electrode group 43 in the direction away from the discharge mechanism device 5. In other embodiments of this application, the number of molybdenum electrode groups may also be 5, 7, etc., and this application does not limit it.

[0071] Please see Figure 2 In some embodiments of this application, the molybdenum electrode auxiliary heating device 4 further includes a first cooling water jacket 402, a first fixed flange 401, and a first protective gas inlet pipe 403. The molybdenum electrode 404 is threadedly connected to the first cooling water jacket 402. The first cooling water jacket 402 is installed on the side of the melting section chamber 12 through the first fixed flange 401. The installation angle of the molybdenum electrode 404 is horizontal at 45° downward. The first protective gas inlet pipe 403 is fixed on both sides of the first cooling water jacket 402 and is used to introduce nitrogen gas to protect the molybdenum electrode 404.

[0072] The molybdenum electrode 404 can be cooled by the first cooling water jacket 402, and nitrogen gas can be introduced through the first protective gas inlet pipe 403 to protect the molybdenum electrode 404. Since the molybdenum electrode 404 is threadedly connected to the first cooling water jacket 402, the molybdenum electrode 404 can be moved into or out of the furnace by rotating the molybdenum electrode 404.

[0073] In some embodiments of this application, the discharge mechanism device 5 includes a tungsten rod 51, a second cooling water jacket 52, a second fixed flange 53, a second protective gas inlet pipe 54, and an induction heating coil 55. The tungsten rod 51 is threadedly connected to the second cooling water jacket 52, and the second cooling water jacket 52 is fixed to the side of the melting section chamber 12 through the second fixed flange 53. The second protective gas inlet pipe 54 is disposed on both sides of the second cooling water jacket 52 for introducing nitrogen gas to protect the tungsten rod 51. The induction heating coil 55 is sleeved on the tungsten rod 51 for induction heating of the tungsten rod 51. The induction heating coil 55 is connected to a high-frequency induction heating power supply.

[0074] In some embodiments of this application, the power of the high-frequency induction heating power supply is adjustable, with a maximum power of 30kW.

[0075] The tungsten rod 51 can be induction heated to prevent the molten glass from condensing and causing blockages during overflow. The induction heating coil 55 can raise the temperature of the tungsten rod to 1000°C in a short time, which helps to promote the discharge process and balance the temperature distribution of the discharged molten glass. Since the tungsten rod 51 is threadedly connected to the second cooling water jacket 52, the tungsten rod 51 can be moved into or out of the furnace by rotating it.

[0076] In some embodiments of this application, the induction heating coil 55 and the high-frequency induction heating power supply can be the SWP-65MT type induction heating equipment manufactured by Chengdu Jinkezhi Electronics Co., Ltd., with RS485 communication control.

[0077] In some embodiments of this application, the longitudinal distance between the tungsten rod 51 and the bottom of the molten section chamber 12 is not less than 50 mm.

[0078] The longitudinal distance between the tungsten rod 51 and the bottom of the melting chamber 12 is not less than 50 mm. Its advantage lies in that, under the condition that the initial thickness of the bottom glass layer on the horizontal side of the tungsten rod in the furnace is greater than 50 mm, it can effectively protect the bottom refractory material from the erosion by the plasma torch flame. When the amount of waste and glass added into the furnace increases, the liquid level of the molten glass in the furnace rises. When the tungsten rod 51 moves outward and is pulled out, the molten glass above the 50 mm level can be discharged from the overflow port.

[0079] In some embodiments of this application, the distance between the end of the molybdenum electrode 404 and the bottom of the molten section chamber 12 is greater than the distance between the tungsten rod 51 and the bottom of the molten section chamber 12.

[0080] The longitudinal distance between the end of the molybdenum electrode and the bottom of the melting chamber 12 is greater than the longitudinal distance between the tungsten rod 51 and the bottom of the melting chamber 12. Its advantage is that after the material is discharged (i.e., only the bottom glass below the overflow port remains in the furnace), there is no glass liquid load between the positive and negative molybdenum electrodes, and a current path cannot be formed. This can be used as a basis for judging whether the glass liquid in the furnace has been completely discharged.

[0081] In some embodiments of this application, there are multiple control transmission devices 6, which correspond to the number of discharge mechanism devices 5 and molybdenum electrode auxiliary heating devices 4. Each control transmission device 6 includes a motor 64, a reducer 63, a drive gear 62 and a driven gear 61 connected in sequence. The rotation center of the driven gear 61 is fixedly connected to the corresponding molybdenum electrode 404 or tungsten rod 51, and is used to drive the tungsten rod 51 or molybdenum electrode 404 to move into or out of the furnace.

[0082] Motor 64 drives reducer 63 to rotate, reducer 63 drives drive gear 62 to rotate, drive gear 62 drives driven gear 61 to rotate, driven gear 61 drives tungsten rod 51 or molybdenum electrode 404 coaxial with it to rotate, and tungsten rod 51 or molybdenum electrode 404 moves into or out of the furnace under the action of the thread. It should be noted that since driven gear 61 is fixedly connected to tungsten rod 51 or molybdenum electrode 404, driven gear 61 will move together with tungsten rod 51 or molybdenum electrode 404. Therefore, drive gear 62 or driven gear 61 should have a certain height, or drive gear 62 can also move synchronously with driven gear 61 through a moving mechanism.

[0083] In some embodiments of this application, the motor 64 may be a three-phase permanent magnet synchronous motor with a torque of 6.0 Nm and a speed of 60 r / min. In other embodiments of this application, the motor 64 may also be other types of motors, and this application does not limit the types of motors used.

[0084] In some embodiments of this application, the speed ratio of the reducer controlling the tungsten rod can be 1:100, and the speed ratio of the reducer controlling the molybdenum electrode can be 1:50.

[0085] In this embodiment, the number of control transmission devices 6 is 7, of which 6 are used to control 6 molybdenum electrodes and 1 is used to control a tungsten rod. In other embodiments of this application, the number of control transmission devices 6 may be other numbers, such as 16 or 20, etc., and this application does not limit the number.

[0086] In some embodiments of this application, the tungsten rod 51 moves into or out of the furnace at a speed of 100 mm / min. This speed prevents the tungsten rod from exiting too quickly, thus avoiding the impact of the overflowing molten glass on the refractory material due to inertial force, and also prevents excessive temperature fluctuations in the furnace caused by the rapid outflow of molten glass at the moment of discharge.

[0087] In some embodiments of this application, the speed at which the molybdenum electrode 404 moves into or out of the furnace is 200 mm / min. This speed can effectively ensure that the molybdenum electrode 404 is inserted into the molten pool within a certain time. During the insertion process, the molybdenum electrode 404 is slowly preheated to avoid the service life of the molybdenum electrode 404 itself being affected by thermal shock.

[0088] The control transmission device 6 can drive the molybdenum electrode 404 to enter and exit at a speed of 200 mm / min. Its advantage is that the molybdenum electrode 404 is only put into use quickly during the discharge stage. During the use of the molybdenum electrode 404, the plasma torch 2 is turned off, which can effectively avoid the oxidation and corrosion of the molybdenum electrode 404 in the high-temperature environment. During the non-use stage, the molybdenum electrode 404 is in the withdrawn state. Under the conditions of cooling water jacket and nitrogen protective gas, it can be prevented from being oxidized by high temperature and its service life is extended.

[0089] Secondly, this application also provides an automatic discharge method for a plasma high-temperature melting device, comprising:

[0090] S1: Initialize the discharge system; ensure that the molybdenum electrode 404 is in the withdrawn state, the tungsten rod 51 is in the closed state (in position), and the plasma torch 2 is in the running state;

[0091] S2: Determine whether the plasma torch is turned on; if not, return to step S1; if yes, proceed to step S3.

[0092] S3: Determine whether the temperatures monitored by the first temperature monitoring group 31 are all greater than 800℃; if not, perform a no-operation; if yes, proceed to step S4.

[0093] S4: Drive the first molybdenum electrode group 41 to move into the furnace at a speed of 200 mm / min, that is, simultaneously start the two motors 64 corresponding to the first molybdenum electrode group 41, and turn off the motors after reaching the limit.

[0094] S5: Set the heating power of the first molybdenum electrode group 41; that is, turn on the two DC power supplies corresponding to the first molybdenum electrode group 41 and set the power to 3kW.

[0095] S6: Turn off plasma torch 2, that is, set the operating current of plasma torch 2 to 0 and disconnect the circuit power supply contactor;

[0096] S7: Determine whether the temperatures monitored by the second temperature monitoring group 32 are all greater than 800℃; if not, perform a no-operation and return to step S7; if yes, proceed to step S8.

[0097] S8: Drive the second molybdenum electrode group 42 to move into the furnace, that is, simultaneously start the two motors 64 corresponding to the second molybdenum electrode group 42, so that they both move into the furnace at a speed of 200 mm / min, and stop after reaching the limit.

[0098] S9: Set the heating power of the second molybdenum electrode group 42, that is, turn on the DC power supply corresponding to the second molybdenum electrode group 42 and set the power to 5kW;

[0099] S10: Determine whether the temperatures monitored by the third temperature monitoring group 33 are all greater than 800℃; if not, perform a no-operation and return to step S10; if yes, proceed to step S11.

[0100] S11: Drive the third molybdenum electrode group 43 into the furnace, that is, simultaneously start the motor 64 corresponding to the third molybdenum electrode group 43, so that they all move into the furnace at a speed of 200mm / min, and turn off the motor after reaching the limit.

[0101] S12: Set the heating power of the third molybdenum electrode group 43, that is, turn on the DC power supply corresponding to the third molybdenum electrode group 43 and set the power to 7kW.

[0102] S13: Determine if all infrared temperature monitors are above 1100℃; if not, perform a no-operation and return to step S13; if yes, proceed to step S14.

[0103] S14: Start the induction heating coil 55, that is, turn on the power of the induction heating coil and set the power to 20kW;

[0104] S15: Start the discharge motor (retract); that is, start the motor 64 corresponding to the tungsten rod 51, so that it retracts to the outside of the furnace at a speed of 100mm / min, and shuts off the motor after reaching the limit.

[0105] S16: Determine whether the discharge is complete; if the power output of the three molybdenum electrode groups is not 0, it means that there is still conductive glass liquid load between the molybdenum electrodes and the glass body has not been completely discharged. Perform an empty operation and proceed to step S16; if the power output of the three molybdenum electrode groups is reduced to 0, it means that the glass body in the furnace has completely flowed out; proceed to step S17.

[0106] S17: Start the discharge motor (in); that is, start the motor 64 corresponding to the tungsten rod 51, so that it moves into the furnace at a speed of 100mm / min, and shuts off the motor after reaching the limit.

[0107] S18: Turn off the power supply to the induction heating coil 55; that is, turn off the power supply to the induction heating coil 55 so that its power is 0 and turn off the power supply circuit contactor.

[0108] S19: Drive all molybdenum electrodes 404 to move outward from the furnace, that is, simultaneously start the motor 64 corresponding to the molybdenum electrode 404, so that they all move outward from the furnace at a speed of 200mm / min. After reaching the limit, turn off the motor and shut off the power supply to the three sets of molybdenum electrodes to complete the discharge.

[0109] In summary, by utilizing the plasma high-temperature melting device and automatic discharge method proposed in this invention, the problem of large temperature gradient in the molten pool can be effectively solved, the temperature uniformity of the molten pool can be improved, thereby enhancing the fluidity of the glass, promoting the discharge process, and preventing accidents caused by glass condensation at the discharge port. Through the automatic control of sensors and actuators, the service life and processing efficiency of the system can be effectively improved, and costs can be reduced.

[0110] Unless otherwise specified, the methods, processes, and apparatus involved in this invention are all based on existing technology or commercially available instruments and equipment.

[0111] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A plasma high-temperature melting device, characterized in that, include: A plasma high-temperature pyrolysis melting furnace (1) is provided with a plasma torch (2), an infrared temperature monitoring device (3), a molybdenum electrode auxiliary heating device (4), a discharge mechanism device (5), and a control and transmission device (6); the infrared temperature monitoring device (3) is used to monitor the temperature of the molten glass in the plasma high-temperature pyrolysis melting furnace (1) in real time; the molybdenum electrode auxiliary heating device (4) is used to provide auxiliary heating for the molten glass; the control and transmission device (6) is used to control the motion of the molybdenum electrode auxiliary heating device (4) and the discharge mechanism device (5); The plasma high-temperature pyrolysis melting furnace (1) is L-shaped, including a vertically arranged vertical furnace section chamber (11) and a horizontally arranged melting section chamber (12). The molybdenum electrode auxiliary heating device (4) includes multiple molybdenum electrode groups. Each molybdenum electrode group includes two molybdenum electrodes (404) symmetrically arranged on the side of the molten section chamber (12). The molybdenum electrodes (404) can insert their ends into the molten pool to heat the glass melt. Each molybdenum electrode group is powered by an independent DC power supply. The molybdenum electrode auxiliary heating device (4) further includes a first cooling water jacket (402), a first fixed flange (401), and a first protective gas inlet pipe (403). The molybdenum electrode is threadedly connected to the first cooling water jacket (402). The first cooling water jacket (402) is installed on the side of the melting section chamber (12) through the first fixed flange (401). The installation angle of the molybdenum electrode is horizontal 45° downward. The first protective gas inlet pipe (403) is fixed on both sides of the first cooling water jacket (402) and is used to introduce nitrogen gas to protect the molybdenum electrode. The discharge mechanism (5) includes a tungsten rod (51), a second cooling water jacket (52), a second fixed flange (53), a second protective gas inlet pipe (54), and an induction heating coil (55). The tungsten rod (51) is threadedly connected to the second cooling water jacket (52). The second cooling water jacket (52) is fixed to the side of the melting section chamber (12) through the second fixed flange (53). The second protective gas inlet pipe (54) is located on both sides of the second cooling water jacket (52) and is used to introduce nitrogen gas to protect the tungsten rod (51). The induction heating coil (55) is sleeved on the tungsten rod (51) and is used to induction heat the tungsten rod (51). The induction heating coil (55) is connected to a high-frequency induction heating power supply.

2. The plasma high-temperature melting device as described in claim 1, characterized in that: The vertical furnace section chamber (11) includes a waste preheating and drying section, a waste pyrolysis and gasification section and an oxidation section connected sequentially from top to bottom, and the melting section chamber (12) is located below the oxidation section.

3. The plasma high-temperature melting device as described in claim 2, characterized in that: The side walls of the vertical furnace section chamber (11) and the melting section chamber (12) include, from the inside out, high-chromium electromolten material, crack-resistant sealing material, mullite lightweight insulating brick, zirconium-containing aluminum silicate fiber board, nano-insulation board and metal shell.

4. The plasma high-temperature melting device as described in claim 1, characterized in that: The plasma torch (2) is installed on top of the molten section chamber (12) with a horizontal tilt angle of 45° downward; and / or, the plasma torch (2) is a non-transfer DC plasma torch with nitrogen as the gas medium and the plasma torch (2) is connected to a plasma torch power supply; and / or, the infrared temperature monitoring device (3) includes multiple infrared temperature monitors, which are arranged in pairs, and the two infrared temperature monitors in each pair are symmetrically arranged on the side of the molten section chamber (12); and / or, the infrared temperature monitoring device (3) is installed with a vertical tilt angle of 45° downward.

5. The plasma high-temperature melting device as described in claim 1, characterized in that: The longitudinal distance between the tungsten rod (51) and the bottom of the molten section chamber (12) is not less than 50 mm; and / or, the distance between the end of the molybdenum electrode and the bottom of the molten section chamber (12) is greater than the distance between the tungsten rod (51) and the bottom of the molten section chamber (12).

6. The plasma high-temperature melting apparatus as described in claim 1, characterized in that: The number of control transmission devices (6) is multiple, and each control transmission device (6) includes a motor (64), a reducer (63), a drive gear (62) and a driven gear (61) connected in sequence. The rotation center of the driven gear (61) is threadedly connected to the water jacket of the corresponding molybdenum electrode (404) or tungsten rod (51) to drive the tungsten rod (51) or molybdenum electrode to move into or out of the furnace; and / or, the speed at which the tungsten rod (51) moves into or out of the furnace is 100 mm / min; and / or, the speed at which the molybdenum electrode moves into or out of the furnace is 200 mm / min.

7. An automatic discharge method for a plasma high-temperature melting device, characterized in that, The apparatus according to any one of claims 1-6 comprises: S1: Initialize the discharge system; ensure that the molybdenum electrode (404) is in the withdrawn state, the tungsten rod (51) is in the closed state, and the plasma torch (2) is in the running state; S2: Determine whether the plasma torch is turned on; if not, return to step S1; if yes, proceed to step S3. S3: Determine whether the temperature monitored by a group of infrared temperature monitors near the discharge mechanism device (5) is greater than 800℃; if not, perform no operation; if yes, proceed to step S4. S4: Drive the molybdenum electrode group close to the discharge mechanism device (5) to move into the furnace at a speed of 200 mm / min, and stop after reaching the limit; S5: Set the heating power of the molybdenum electrode group near the discharge mechanism device (5) to 3~5kW; S6: Turn off the plasma torch (2); S7: Determine whether the temperatures monitored by the group of infrared temperature monitors located in the middle are all greater than 800℃; if not, perform a no-operation; if yes, proceed to step S8; S8: Drives the molybdenum electrode group located in the middle to move into the furnace at a speed of 200 mm / min, and stops after reaching the limit. S9: Set the heating power of the molybdenum electrode group located in the middle to 5~7kW; S10: Determine whether the temperature monitored by a group of infrared temperature monitors far away from the discharge mechanism device (5) is greater than 800℃; if not, perform no operation; if yes, proceed to step S11. S11: Drive the molybdenum electrode group away from the discharge mechanism (5) to move into the furnace at a speed of 200 mm / min, and stop after reaching the limit; S12: Set the heating power of the molybdenum electrode group that is far away from the discharge mechanism device (5) to 7~9kW; S13: Determine if all infrared temperature monitors are above 1100℃; if not, perform a no-operation; if yes, proceed to step S14. S14: Start the induction heating coil (55), the power of which is 15~25kW; S15: Start the control motor of the tungsten rod (51) so that it moves out of the furnace at a speed of 100 mm / min and stops when it reaches the limit. S16: Determine whether the material discharge is complete; if the power output of all molybdenum electrodes is not 0, perform a no-operation and proceed to step S16; if all are 0, proceed to step S17. S17: Start the control motor of the tungsten rod (51) so that it moves into the furnace at a speed of 100 mm / min and stops when it reaches the limit. S18: Turn off the power to the induction heating coil (55); S19: Drive all molybdenum electrodes to move outward from the furnace at a speed of 200 mm / min. Stop when they reach the limit, turn off the power supply to all molybdenum electrodes, and complete the discharge.

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