A control method, apparatus, equipment, and storage medium for a plasma arc melting furnace.

Abstract

This application relates to a control method, apparatus, equipment, and storage medium for a plasma arc melting furnace. The melting furnace is used to treat secondary hazardous waste. The furnace includes a constant current source, a first electrode, and a second electrode. The constant current source is connected to both the first and second electrodes, and its output current is introduced into the furnace through the electrodes. The method includes: adjusting the height of the first and second electrodes until they contact the secondary hazardous waste inside the furnace; wherein the surface of the secondary hazardous waste is covered with an arc-initiating agent; after successful arc ignition, adjusting the output current of the constant current source based on the arc voltage and furnace temperature; if the furnace temperature meets a second preset condition, adjusting the output current based on a preset increment; and after the arc power reaches a target power, adjusting the height of the first and second electrodes based on the difference between the arc power and the target power. This solves the problems of difficult arc ignition and inconsistent output power when the melting furnace treats secondary hazardous waste.

Description

Technical Field

[0001] This invention relates to the field of furnace control technology, and in particular to a control method, apparatus, equipment and storage medium for a plasma arc melting furnace. Background Technology

[0002] Secondary hazardous waste refers to new hazardous waste generated after primary hazardous waste has been reprocessed, such as slag and fly ash produced after incineration. These secondary hazardous wastes typically contain harmful chemicals or radioactive elements and require special treatment to ensure safety; otherwise, they will increase the risks to the environment and human health.

[0003] Melt solidification technology is an effective method for treating secondary hazardous waste. It primarily involves mixing hazardous waste with fine glassy particles, then melting the mixture at high temperatures. The resulting vitrified solid ensures the permanent stability of the waste. One of the key steps in this process is melting the secondary hazardous waste.

[0004] Plasma arc melting furnaces are a common type of melting equipment. Their principle involves applying sufficient voltage or current between two electrodes inside the furnace. The current flows through the air gap between the electrodes, forming an electric arc. The high temperature of the arc converts electrical energy into heat energy, causing the material to reach its melting point and melt. However, electrode discharge requires a specific distance, such as 3-5 mm, otherwise discharge is impossible. Therefore, plasma arc melting furnaces are often used for metallic materials because metallic materials are conductive and can act as part of the electrodes during operation. However, secondary hazardous waste is usually insulated, making it difficult to meet the required discharge distance between electrodes. Current technologies address this issue by using other heat sources, such as burners or plasma cabinets, to partially melt the material before use. This method not only increases operational complexity but also raises equipment costs and operating expenses.

[0005] Secondly, plasma arc melting furnaces typically use a constant voltage source, which presents a challenge in maintaining a constant arc power when melting secondary hazardous waste. This is because secondary hazardous waste has a complex composition, and its resistance fluctuates significantly during heating, leading to substantial changes in current and making arc power difficult to control. Excessive power fluctuations can result in uneven melting of the material, affecting processing efficiency. Therefore, an effective control method is urgently needed to address these issues. Summary of the Invention

[0006] According to a first aspect of this disclosure, a control method for a plasma arc melting furnace is provided. The melting furnace is used to treat secondary hazardous waste. The melting furnace includes a constant current source, a first electrode, and a second electrode. The constant current source is connected to the first electrode and the second electrode, respectively. The output current of the constant current source is introduced into the furnace through the electrodes. The method includes:

[0007] The heights of the first electrode and the second electrode are adjusted until they come into contact with the secondary hazardous waste inside the melting furnace; wherein the surface of the secondary hazardous waste is covered with an arc-initiating agent.

[0008] After successful arc ignition, the output current of the constant current source is adjusted based on the arc voltage and furnace temperature.

[0009] If the furnace temperature meets the second preset condition, the output current is adjusted based on the preset increment.

[0010] After the arc power is increased to the target power, the height of the first electrode and the second electrode is adjusted based on the difference between the arc power and the target power.

[0011] According to a second aspect of this disclosure, a control device for a plasma arc melting furnace is provided. The melting furnace is used to treat secondary hazardous waste. The melting furnace includes a constant current source, a first electrode, and a second electrode. The constant current source is connected to the first electrode and the second electrode, respectively. The output current of the constant current source is introduced into the furnace through the electrodes. The device includes:

[0012] An electrode control module is used to adjust the height of the first electrode and the second electrode until they come into contact with the secondary hazardous waste in the melting furnace; wherein the surface of the secondary hazardous waste is covered with an arc-initiating agent.

[0013] The temperature control module is used to adjust the output current of the constant current source based on the arc voltage and the furnace temperature after successful arc ignition.

[0014] The power control module is used to adjust the output current based on a preset increment if the furnace temperature meets the second preset condition.

[0015] A power stabilization module is used to adjust the height of the first electrode and the second electrode based on the difference between the arc power and the target power after the arc power has been increased to the target power.

[0016] According to a third aspect of this disclosure, an electronic device is provided, comprising: at least one processor; and a memory for storing processor-executable instructions; wherein the at least one processor is configured to execute the instructions to implement the method described in the first aspect of this disclosure.

[0017] According to a fourth aspect of this disclosure, a computer-readable storage medium is provided having a computer program stored thereon, characterized in that, when the computer program is executed by a processor, it implements the method described in the first aspect of this disclosure.

[0018] This disclosure provides a control method, apparatus, equipment, and storage medium for a plasma arc melting furnace. On one hand, by covering the surface of secondary hazardous waste with an arc-initiating agent, the discharge distance between electrodes is prevented from failing to meet requirements due to the insulating properties of the hazardous waste, thus improving the arc ignition success rate. Compared to existing methods using other heat sources, this reduces operational difficulty and lowers equipment and operating costs. On the other hand, a constant current source replaces the constant voltage source commonly used in existing plasma arc melting furnaces. The current is controlled by adjusting the output current of the constant current source, and the contact area between the electrodes and the furnace material is changed by adjusting the height of the first and second electrodes, thereby indirectly controlling the arc voltage. Selective control of both at different stages maintains a constant output power. On the other hand, adjusting the output current of the constant current source indirectly controls the furnace temperature. During the heating phase after successful arc ignition, the output current is adjusted based on the arc voltage and furnace temperature, preventing arc interruption caused by abnormal arc voltage while simultaneously increasing the temperature. Attached Figure Description

[0019] Further details, features, and advantages of this disclosure are disclosed in the following description of exemplary embodiments in conjunction with the accompanying drawings, in which:

[0020] Figure 1 A flowchart of a control method for a plasma arc melting furnace provided as an exemplary embodiment of this disclosure;

[0021] Figure 2 A flowchart of a method for adjusting the output current of a constant current source based on arc voltage and furnace temperature, provided as an exemplary embodiment of this disclosure;

[0022] Figure 3 A flowchart illustrating a method for adjusting output current based on furnace temperature, provided as an exemplary embodiment of this disclosure;

[0023] Figure 4 A flowchart of a method for adjusting output current based on furnace temperature and a preset temperature change curve, provided as an exemplary embodiment of this disclosure;

[0024] Figure 5 A flowchart illustrating a method for adjusting the output current based on a preset increment, as provided in an exemplary embodiment of this disclosure;

[0025] Figure 6 A schematic block diagram of a control device for a plasma arc melting furnace provided as an exemplary embodiment of the present disclosure;

[0026] Figure 7 A schematic block diagram of an electronic device provided as an exemplary embodiment of this disclosure;

[0027] Figure 8 A block diagram of a computer system provided for an exemplary embodiment of this disclosure. Detailed Implementation

[0028] Embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings. While some embodiments of this disclosure are shown in the drawings, it should be understood that this disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this disclosure. It should be understood that the accompanying drawings and embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure.

[0029] It should be understood that the steps described in the method embodiments of this disclosure may be performed in different orders and / or in parallel. Furthermore, the method embodiments may include additional steps and / or omit the steps shown. The scope of this disclosure is not limited in this respect.

[0030] The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Definitions of other terms will be given in the description below. It should be noted that the concepts of "first", "second", etc., used in this disclosure are only used to distinguish different devices, modules, or units, and are not intended to limit the order of functions performed by these devices, modules, or units or their interdependencies.

[0031] It should be noted that the terms "a" and "a plurality of" used in this disclosure are illustrative rather than restrictive, and those skilled in the art should understand that, unless otherwise expressly indicated in the context, they should be understood as "one or more".

[0032] The names of messages or information exchanged between multiple devices in the embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of such messages or information.

[0033] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0034] In this embodiment of the present disclosure, the plasma arc melting furnace is used to treat secondary hazardous waste. The melting furnace includes a constant current source, a first electrode, and a second electrode. The constant current source is connected to the first electrode and the second electrode, respectively. The output current of the constant current source is introduced into the furnace through the electrodes. Figure 1 A flowchart illustrating a control method for a plasma arc melting furnace provided as an exemplary embodiment of this disclosure. Figure 1 As shown, the above control method includes the following steps:

[0035] Step S102: Adjust the height of the first electrode and the second electrode until they come into contact with the secondary hazardous waste in the melting furnace; wherein the surface of the secondary hazardous waste is covered with an arc-initiating agent.

[0036] This disclosure does not limit the initial positions of the first electrode and the second electrode. Optionally, the first electrode and the second electrode may be located above the melting furnace. Optionally, the first electrode and the second electrode may also be located inside the melting furnace.

[0037] This disclosure does not limit the types of the first electrode and the second electrode described above. Optionally, the electrode can be a carbon electrode, a graphite electrode, or a metal electrode. In one optional embodiment, the first electrode and the second electrode are graphite electrodes, which have high heat resistance and high electrical conductivity, and can better achieve the purpose of arc heating and melting materials.

[0038] This disclosure does not limit the relative positions of the first and second electrodes. Optionally, the first and second electrodes are arranged in parallel. Optionally, the first and second electrodes may have the same or different heights.

[0039] This disclosure does not limit the specific type of the arc-initiating agent, as long as it helps to form an arc between the first and second electrodes. In an optional embodiment, the arc-initiating agent is a conductive solid. Optionally, the arc-initiating agent may include one or more of metallic conductor materials, semiconductor materials, and conductive polymers. Preferably, the arc-initiating agent is coke or graphite.

[0040] This disclosure does not limit the coverage area of ​​the arc-initiating agent; it can cover the entire secondary hazardous waste inside the melting furnace, or it can partially cover the secondary hazardous waste inside the melting furnace. Preferably, the surface of the secondary hazardous waste is covered with the arc-initiating agent along the line connecting the first electrode and the second electrode, which can increase the probability of arc formation.

[0041] This disclosure does not limit the specific manner in which the heights of the first electrode and the second electrode are adjusted. In one optional embodiment, adjusting the heights of the first electrode and the second electrode until they contact the secondary hazardous waste in the melting furnace includes: adjusting the heights of the first electrode and the second electrode until they contact the arc-initiating agent covering the secondary hazardous waste in the melting furnace.

[0042] In another optional embodiment, the melting furnace further includes a first electrode clamping part and a second electrode clamping part, wherein the first electrode clamping part is used to clamp the first electrode and the second electrode clamping part is used to clamp the second electrode.

[0043] The aforementioned adjustment of the heights of the first electrode and the second electrode until they come into contact with the secondary hazardous waste inside the melting furnace includes:

[0044] Obtain the torque values ​​of the first electrode clamping part and the second electrode clamping part;

[0045] When the torque value of the first electrode clamping part or the second electrode clamping part is less than the preset torque value, the height of the first electrode and the second electrode is lowered.

[0046] When the torque value of the first electrode clamping part or the second electrode clamping part is equal to the preset torque value, the adjustment of the height of the first electrode and the second electrode is stopped.

[0047] When the torque value of the first electrode clamping part or the second electrode clamping part is greater than the preset torque value, the height of the first electrode and the second electrode is raised.

[0048] In this embodiment, the preset torque value is the upper limit of the torque value that the first electrode clamping part and the second electrode clamping part can withstand. When the torque value of the first electrode clamping part or the second electrode clamping part is greater than or equal to the preset torque value, it indicates that the height of the first electrode or the second electrode cannot be lowered further. In other words, the first electrode or the second electrode has already made sufficiently close contact with the secondary hazardous waste in the melting furnace.

[0049] In an optional embodiment, after adjusting the heights of the first electrode and the second electrode until they contact the secondary hazardous waste inside the melting furnace, the method further includes:

[0050] Set the initial output current of the constant current source;

[0051] Start the constant current source mentioned above to attempt to ignite an arc.

[0052] This embodiment does not limit the specific value of the initial output current of the constant current source. Optionally, the initial output current of the constant current source can be a value greater than the minimum allowable current of the constant current source, as long as the current value is low. Preferably, the initial output current of the constant current source can be the minimum allowable current of the constant current source. Since secondary hazardous waste is non-conductive when cold and has a complex composition resulting in high resistance, choosing a low current to attempt arc ignition can minimize the risk of the instantaneous voltage exceeding the maximum voltage that the constant current source can withstand during arc formation, thus preventing arc ignition failure. Optionally, the initial output current of the constant current source can be any value between 10A and 20A. Preferably, the initial output current is 10A.

[0053] This implementation does not limit the specific method for determining whether arc ignition was successful or failed. Optionally, after starting the constant current source, the following may also be included:

[0054] Monitor arc voltage;

[0055] If the arc voltage is greater than the upper limit of the safe voltage or less than the lower limit of the safe voltage, the arc ignition is considered to have failed.

[0056] If the arc voltage is not greater than the upper limit of the safe voltage and not less than the lower limit of the safe voltage, the arc is considered to have been successfully ignited.

[0057] The aforementioned upper limit of the safe voltage is the maximum allowable voltage value of the constant current source, and also the maximum voltage value for maintaining the arc. The aforementioned lower limit of the safe voltage is the minimum allowable voltage value of the constant current source, and also the minimum voltage value for maintaining the arc. The applicant discovered that during the arc ignition stage, if the arc voltage exceeds the upper limit of the safe voltage after the constant current source is turned on, it will cause an open circuit, preventing the formation of an arc, meaning arc ignition failure. If the arc voltage is less than the lower limit of the safe voltage, a short circuit will occur, also preventing the formation of an arc, meaning arc ignition failure. Therefore, by understanding the relationship between the arc voltage and the two values ​​of "upper limit of safe voltage" and "lower limit of safe voltage," the success or failure of arc ignition can be effectively determined.

[0058] This embodiment does not limit the specific values ​​of the upper and lower safety voltage limits. It is understood that the upper and lower safety voltage limits will differ for different specifications of constant current sources. Preferably, the upper safety voltage limit is 350V and the lower safety voltage limit is 30V.

[0059] Optionally, if the arc voltage is greater than the upper limit of the safe voltage or less than the lower limit of the safe voltage, the arc ignition is considered to have failed, including: if the arc voltage at a certain moment is greater than the upper limit of the safe voltage or less than the lower limit of the safe voltage, the arc ignition is considered to have failed.

[0060] Optionally, the statement that arc ignition is considered successful if the arc voltage is not greater than the upper limit of the safe voltage and not less than the lower limit of the safe voltage includes: if the arc voltage is not greater than the upper limit of the safe voltage and is greater than or less than the lower limit of the safe voltage within a preset time, arc ignition is considered successful. Setting a preset time helps determine whether the arc voltage can be stably maintained within the safe voltage range, rather than judging solely by the instantaneous arc voltage, thus improving the accuracy of arc ignition judgment. Optionally, the preset time is any value between 10 and 30 seconds.

[0061] This disclosure does not limit the specific control method after arc ignition failure. In an optional implementation, the above method further includes:

[0062] If arc ignition fails, obtain the furnace temperature;

[0063] Based on the furnace temperature, adjust the output current of the constant current source or add an arc-initiating agent to the surface of the secondary hazardous waste;

[0064] Restart the constant current source to attempt to ignite an arc.

[0065] Optionally, adjusting the output current of the constant current source or adding an arc-initiating agent to the surface of the secondary hazardous waste based on the furnace temperature may include:

[0066] If the furnace temperature is higher than or equal to the first preset temperature, adjust the output current of the constant current source mentioned above.

[0067] If the furnace temperature is lower than the first preset temperature, an arc-initiating agent is added to the surface of the aforementioned secondary hazardous waste.

[0068] The control method proposed in this disclosure includes at least three stages: arc ignition stage, arc stabilization stage, and normal operation stage. The arc ignition stage has two application scenarios: cold arc ignition and hot arc ignition. The cold arc ignition stage typically occurs when the plasma arc melting furnace is first started or restarted after a long period of shutdown. Shutdowns can include fault-related shutdowns or scheduled shutdowns. The hot arc ignition stage typically occurs after temporarily shutting down the constant current source and then restarting it, for example, after the plasma arc melting furnace completes slag removal and restarts, or after a short-term normal maintenance. In this embodiment, a first preset temperature is used to identify the critical point between the cold and hot states. A furnace temperature below the first preset temperature indicates that the melting furnace is in a cold state, and a furnace temperature above or equal to the first preset temperature indicates that the melting furnace is in a hot state. Different methods are used to address the two scenarios of cold arc ignition failure and hot arc ignition failure.

[0069] The reason for the failure to ignite the arc in the cold state is that the arc voltage exceeds the upper limit of the safe voltage, causing an open circuit and preventing the formation of an arc. The applicant's analysis revealed that the deeper reason is that the secondary hazardous waste is a solid insulator in the cold state and has a complex composition, resulting in a high resistance value. Even if the initial output current of the constant current source is set to a low current, the arc voltage may still be too high during the arc ignition attempt, leading to the failure of arc ignition.

[0070] To address the issue of arc ignition failure in a cold state, this application proposes adding an arc igniter to the surface of the aforementioned secondary hazardous waste. Since the arc igniter is a conductive solid, its addition increases the conductivity of the secondary hazardous waste, thereby reducing the resistance between the first and second electrodes and ultimately decreasing the arc voltage.

[0071] The reason for arc ignition failure under hot conditions is that the arc voltage is lower than the lower limit of the safe voltage, resulting in a short circuit and preventing the formation of an arc. The melting furnace used in this application employs a constant current source. In an optional embodiment, to solve the problem of arc ignition failure under hot conditions, the output current of the constant current source can be adjusted. That is, under the premise of a constant resistance, the output current is increased to increase the arc voltage, thereby avoiding short circuits and preventing arc ignition failure.

[0072] Optionally, the first preset temperature can be any value between 700 and 900°C. Preferably, the first preset temperature can be 800°C. In this embodiment, adjusting the output current of the constant current source or adding an arc-initiating agent to the surface of the secondary hazardous waste based on the furnace temperature includes: adjusting the output current of the constant current source if the furnace temperature is higher than or equal to 800°C; and adding an arc-initiating agent to the surface of the secondary hazardous waste if the furnace temperature is lower than 800°C.

[0073] Step S104: After successful arc ignition, adjust the output current of the constant current source based on the arc voltage and furnace temperature.

[0074] After successful arc ignition, the control method enters the arc stabilization stage, which requires a rapid increase in furnace temperature. Since the plasma arc melting furnace uses a constant current source, the furnace temperature can be indirectly controlled by adjusting the output current of the constant current source. However, secondary hazardous waste has a complex composition, high resistivity, and high melting point. After successful arc ignition, the secondary hazardous waste remains essentially solid, with minimal change in resistivity. Therefore, the arc voltage changes significantly with the adjustment of the output current. Excessive or insufficient arc voltage can lead to arc interruption. Therefore, in this embodiment, after successful arc ignition, the output current is adjusted based on the arc voltage and furnace temperature to raise the temperature while avoiding arc interruption caused by abnormal arc voltage.

[0075] This disclosure does not limit the specific method of adjusting the output current of the constant current source described above, such as... Figure 2As shown, in an optional embodiment, after successful arc ignition, adjusting the output current of the constant current source based on the arc voltage and furnace temperature may include:

[0076] Step S202: After successful arc ignition, maintain the above output current unchanged and monitor the arc voltage;

[0077] Step S204: If the arc voltage drops to the lower limit of the safe voltage, or if the arc voltage no longer drops within the first time interval and is less than the upper limit of the safe voltage, adjust the output current based on the furnace temperature; wherein, the lower limit of the safe voltage is the minimum voltage to maintain the arc, and the upper limit of the safe voltage is the maximum voltage to maintain the arc.

[0078] If the arc voltage exceeds the upper limit of the safe voltage, it will cause a circuit break, leading to arc interruption. If the arc voltage is lower than the lower limit of the safe voltage, a short circuit will occur, also leading to arc interruption. Therefore, in this embodiment, after successful arc ignition, the output current is maintained constant while monitoring the arc voltage. As the arc continues to heat the secondary hazardous waste, the resistance value gradually decreases, and the arc voltage also decreases accordingly. If the arc voltage drops to the lower limit of the safe voltage, or if the arc voltage no longer decreases within the first time interval and is lower than the upper limit of the safe voltage, it means that the arc voltage is not only within the safe voltage range but also some distance from the upper limit of the safe voltage, making it a suitable time to increase the output current. Adjusting the output current based on the furnace temperature can prevent arc interruption caused by abnormal arc voltage.

[0079] This embodiment does not limit the specific method of adjusting the output current based on the furnace temperature, such as... Figure 3 As shown, in an optional embodiment, the above-mentioned adjustment of the output current based on the furnace temperature may include:

[0080] Step S302: Obtain a preset temperature change curve; wherein, the preset temperature change curve is related to the characteristics of the refractory material in the plasma arc melting furnace.

[0081] Step S304: Adjust the output current based on the furnace temperature and the preset temperature change curve.

[0082] The goal of the arc stabilization stage is to rapidly increase the furnace temperature. However, during the manufacturing of the molten furnace, refractory materials are typically added, such as magnesia-chrome spinel bricks, high-alumina bricks, and prebaked carbon bricks. These refractory materials play a crucial role in the electric arc furnace, protecting the furnace body and preventing further corrosion and heat loss. However, the refractory materials have certain requirements regarding the rate of temperature change. For example, the temperature increase rate cannot be too rapid to avoid thermal stress or cracking of the refractory material during the temperature rise. Optionally, the rate of temperature change needs to be controlled within the range of a few degrees to tens of degrees per minute. Furthermore, the rate of temperature increase needs to be stable to prevent cracking or deformation of the refractory material due to excessive temperature fluctuations.

[0083] In this embodiment, to solve the above problems, a preset temperature change curve is first obtained. This preset temperature change curve is obtained through analysis and experimentation based on the characteristics of the refractory material. Different refractory materials used in the melting furnace will result in different preset temperature change curves. Then, based on the furnace temperature and the preset temperature change curve, the output current is adjusted to make the furnace temperature change as close as possible to the preset temperature change curve, thus preventing the refractory material from cracking or deforming during the heating process.

[0084] This embodiment does not limit the specific method of adjusting the output current based on the furnace temperature, such as... Figure 4 As shown, in an optional embodiment, adjusting the output current based on the furnace temperature and the preset temperature change curve may include:

[0085] Step S401: Obtain the furnace temperature at the current time point;

[0086] Step S402: Based on the furnace temperature at the current time point, determine whether there is a corresponding point on the preset temperature change curve; wherein, the temperature value of the preset temperature change curve at the corresponding point is equal to the furnace temperature at the current time point.

[0087] Step S403: If the preset temperature change curve has a corresponding point, the corresponding point is taken as the first reference point.

[0088] Step S404: Based on the current time point mentioned above, obtain the furnace temperature after a preset second time interval and determine it as the first actual temperature;

[0089] Step S405: Based on the preset temperature change curve, the first reference point, and the preset second time interval, determine the second reference point.

[0090] Step S406: Determine the temperature corresponding to the second reference point as the first target temperature;

[0091] Step S407: Adjust the output current based on the first actual temperature and the first target temperature.

[0092] This embodiment does not limit the specific value of the preset second time interval. Optionally, the preset second time interval can be any value between 5 and 15 seconds. Preferably, the preset second time interval is 10 seconds.

[0093] In this embodiment, at preset second time intervals, the output current is adjusted based on the furnace temperature value and the ideal temperature value corresponding to the preset temperature change curve. This makes the furnace temperature change closer to the preset temperature change curve, which not only allows the furnace temperature to reach the preset temperature as quickly as possible and improves heating efficiency, but also avoids thermal stress or cracking of the heat-resistant material of the melting furnace.

[0094] In an optional implementation, adjusting the output current based on the first actual temperature and the first target temperature may include:

[0095] The first actual temperature and the first target temperature are input into the PID proportional-integral-derivative module to obtain the output result;

[0096] Based on the above output results, determine the adjusted output current.

[0097] Optionally, the output of the PID controller can be the output current value or a parameter related to the output current. Therefore, the adjusted output current can be determined based on the relationship between the above parameters and the output current, thereby controlling the arc power.

[0098] In another alternative implementation, adjusting the output current based on the first actual temperature and the first target temperature may further include:

[0099] Determine the difference between the first actual temperature and the first target temperature mentioned above;

[0100] Based on the difference between the first actual temperature and the first target temperature, the adjusted output current is determined.

[0101] The applicant discovered that during the arc stabilization phase, as the electric arc heats up, the furnace temperature increases, and the hazardous waste in contact with the first and second electrodes gradually changes from a solid to a liquid state. The further the electrodes extend into the furnace, the larger the contact area with the hazardous waste, and the higher the heating efficiency of the electric arc. Therefore, by judging the degree of melting of the secondary hazardous waste, the height of the first and second electrodes can be adjusted at the appropriate time to improve heating efficiency.

[0102] In an optional embodiment, the melting furnace further includes a first electrode clamping part and a second electrode clamping part, wherein the first electrode clamping part is used to clamp the first electrode, and the second electrode clamping part is used to clamp the second electrode. After adjusting the output current of the constant current source based on the arc voltage and the furnace temperature, the furnace further includes:

[0103] A first image is obtained, wherein the first image is an image of the surface of the secondary hazardous waste inside the melting furnace;

[0104] Based on the first image above, determine the intensity or reflectivity of the reflected light from the secondary hazardous waste.

[0105] When the intensity of the reflected light is greater than a predetermined light intensity value or the reflectivity is greater than a predetermined reflectivity, the height of the first electrode and the second electrode is reduced.

[0106] If the torque value of the first electrode clamping part or the second electrode clamping part is greater than or equal to the preset torque value, the adjustment of the height of the first electrode and the second electrode is stopped.

[0107] In this embodiment, the applicant discovered that when hazardous waste is solid, its surface roughness and unevenness result in weak light reflection. As the hazardous waste gradually melts into a liquid, its light reflection becomes stronger. Therefore, based on image analysis, the intensity or reflectivity of the reflected light from the hazardous waste is determined, and the approximate ratio of liquid to solid is judged accordingly, thereby determining the melting ratio. When the reflected light intensity is greater than a predetermined light intensity value or the reflectivity is greater than a predetermined reflectivity, it indicates that a portion of the hazardous waste has melted into a liquid. This allows the height of the first and second electrodes to be lowered, increasing the contact area between the electrodes and the hazardous waste, ultimately improving heating efficiency. Furthermore, by comparing the torque values ​​of the first and second electrode clamping parts with a preset torque value, it can be determined whether the electrodes have descended to the bottom of the melting furnace or cannot descend further.

[0108] In another optional embodiment, the melting furnace further includes a first electrode clamping part and a second electrode clamping part, wherein the first electrode clamping part is used to clamp the first electrode and the second electrode clamping part is used to clamp the second electrode. After adjusting the output current of the constant current source based on the arc voltage and the furnace temperature, the furnace further includes:

[0109] Acquire a second image; wherein the second image includes a first electrode, a second electrode, and at least a portion of secondary hazardous waste;

[0110] Based on the second image described above, the first electrode and the second electrode are identified;

[0111] Determine the texture features of the adjacent regions of the first and second electrodes mentioned above;

[0112] Based on the above texture features, the texture uniformity of the adjacent regions is determined;

[0113] When the texture uniformity of the adjacent regions is greater than a predetermined value, the height of the first and second electrodes is reduced.

[0114] If the torque value of the first electrode clamping part or the second electrode clamping part is greater than or equal to the preset torque value, the adjustment of the height of the first electrode and the second electrode is stopped.

[0115] In this embodiment, the applicant discovered that when hazardous waste is solid, its surface is rough and its texture is uneven; when it melts into a liquid, its surface is smooth and its texture is uniform. Therefore, based on image analysis, the texture uniformity of adjacent areas where the first and second electrodes are located can be determined, and the melting ratio of hazardous waste around the first and second electrodes can be judged. When the texture uniformity of the adjacent areas is greater than a predetermined value, it indicates that the hazardous waste around the first and second electrodes has melted into a liquid, i.e., it is in a molten state. This allows the height of the first and second electrodes to be reduced, increasing the contact area between the electrodes and the hazardous waste, ultimately improving heating efficiency. Furthermore, by comparing the torque values ​​of the first and second electrode clamping parts with a preset torque value, it can be determined whether the electrodes have descended to the bottom of the melting furnace or cannot descend further.

[0116] Step S106: If the furnace temperature meets the second preset condition, adjust the output current based on the preset increment.

[0117] This disclosure does not limit the specific content of the furnace temperature meeting the second preset condition. In an optional embodiment, meeting the second preset condition means that the furnace temperature is greater than the second preset temperature, which is greater than or equal to the melting point of the secondary hazardous waste. Optionally, the second preset temperature can be any value between 800-1100°C. Preferably, the second preset temperature can be 800°C.

[0118] In this embodiment, the purpose of the arc stabilization stage is to raise the furnace temperature above the melting point of the secondary hazardous waste. After the arc stabilization stage, the normal operation stage begins. The normal operation stage includes two sub-stages: the arc power enhancement stage and the arc power stabilization stage. Since the arc power has not yet reached the ideal output power at the end of the arc stabilization stage, the goal of the power enhancement stage is to increase the arc power to the target power.

[0119] In one alternative implementation, such as Figure 5 As shown, if the furnace temperature meets the second preset condition, the output current is adjusted based on a preset increment, including:

[0120] Step S502: If the furnace temperature is greater than the second preset temperature, adjust the output current based on the preset increment; wherein the second preset temperature is greater than or equal to the melting point of the secondary hazardous waste.

[0121] This embodiment does not limit the specific value of the preset increment. The preset increment depends on the maximum value of the output current of the constant current source. Optionally, the maximum value of the output current of the constant current source is any value between 2500A and 4000A. Preferably, the preset increment is 100A.

[0122] Step S504: If the arc voltage is greater than or equal to the upper limit of the safe voltage, reduce the height of the first electrode and the second electrode.

[0123] In this embodiment, the applicant discovered that after adjusting the output current based on a preset increment, the resistance changes very little within a short period of time, and the arc voltage increases accordingly. However, if the arc voltage changes too much, it can cause arc interruption. Therefore, the arc voltage is monitored, and when the arc voltage is greater than or equal to the upper limit of the safe voltage, the height of the first and second electrodes is reduced to increase the contact area between the electrodes and the material, thereby reducing the resistance between the electrodes and indirectly controlling the arc voltage to avoid arc interruption.

[0124] In another optional embodiment, if the furnace temperature meets the second preset condition, adjusting the output current may further include:

[0125] If the furnace temperature is higher than the second preset temperature, the output current is adjusted based on the preset increment.

[0126] After the third time interval, determine whether the arc power is greater than or equal to the target power;

[0127] If the arc power is less than the target power, the output current will be adjusted again based on the preset increment.

[0128] This embodiment does not limit the specific value of the target power, which depends on the performance indicators of the plasma arc melting furnace and the specific composition of the secondary hazardous waste. Preferably, the target power is 500KW.

[0129] This embodiment does not limit the specific value of the third time interval. It is understood that when the output current of the constant current source is changed, it is difficult to immediately and accurately determine the change in arc voltage. Therefore, a third time interval is set to allow time for acquiring the arc voltage, thereby accurately determining the current arc power. Optionally, the aforementioned third time interval can be any value between 1 and 10 seconds. Preferably, the aforementioned third time interval is 5 seconds.

[0130] Step S108: After the arc power is raised to the target power, the height of the first electrode and the second electrode is adjusted based on the difference between the arc power and the target power.

[0131] After the arc power increase stage, the control method enters the power stabilization stage. The goal of the power stabilization stage is to maintain a constant output power (i.e., arc power). In this embodiment, the contact area between the electrodes and the material inside the furnace is changed by adjusting the height of the first and second electrodes, thereby controlling the arc voltage to maintain a constant arc power.

[0132] In an optional implementation, adjusting the height of the first and second electrodes based on the difference between the arc power and the target power includes:

[0133] If the difference between the arc power and the target power is greater than 0, reduce the height of the first electrode and the second electrode.

[0134] If the difference between the arc power and the target power is less than 0, the height of the first electrode and the second electrode is increased.

[0135] Optionally, if the difference between the arc power and the target power is greater than 0, reducing the height of the first electrode and the second electrode may further include:

[0136] When the difference between the above-mentioned arc power and the above-mentioned target power is greater than 0, it is determined whether the torque value of the above-mentioned first electrode clamping part or the above-mentioned second electrode clamping part is greater than or equal to the preset torque value.

[0137] When the torque value of the first electrode clamping part or the second electrode clamping part is greater than or equal to the preset torque value, the output current is reduced.

[0138] When adjusting the electrode height, it may be impossible to lower the height due to reasons such as the electrode already touching the bottom of the melting furnace. Therefore, when the torque value of the first electrode clamping part or the second electrode clamping part is greater than or equal to the preset torque value, it is considered that the first electrode or the second electrode can no longer be lowered, and the output power is kept constant by reducing the output current.

[0139] This disclosure proposes a control method for a plasma arc melting furnace. On one hand, by covering the surface of secondary hazardous waste with an arc-initiating agent, the discharge distance between electrodes is prevented from failing to meet requirements due to the insulating properties of the hazardous waste, thus improving the arc ignition success rate. Compared with existing technologies that rely on other heat sources, this method reduces operational difficulty and lowers equipment and operating costs. On the other hand, a constant current source is used instead of the constant voltage source commonly used in existing arc melting furnaces. The current is controlled by adjusting the output current of the constant current source, and the contact area between the electrodes and the material inside the furnace is changed by adjusting the height of the first and second electrodes, thereby indirectly controlling the arc voltage. Selective control of both at different stages maintains a constant output power. On the other hand, adjusting the output current of the constant current source can indirectly control the furnace temperature. During the heating stage after successful arc ignition, the output current is adjusted based on the arc voltage and the furnace temperature, preventing arc interruption caused by abnormal arc voltage while simultaneously increasing the temperature.

[0140] This disclosure also provides a control device 600 for a plasma arc melting furnace, which is used to treat secondary hazardous waste. The furnace includes a constant current source, a first electrode, and a second electrode. The constant current source is connected to the first electrode and the second electrode, respectively. The output current of the constant current source is introduced into the furnace through the electrodes. Figure 6 As shown, the above-mentioned device includes:

[0141] Electrode control module 601 is used to adjust the height of the first electrode and the second electrode until they come into contact with the secondary hazardous waste in the melting furnace; wherein the surface of the secondary hazardous waste is covered with an arc-initiating agent.

[0142] The temperature control module 602 is used to adjust the output current of the constant current source based on the arc voltage and the furnace temperature after successful arc ignition.

[0143] The power control module 603 is used to adjust the output current based on a preset increment if the furnace temperature meets the second preset condition.

[0144] The power stabilization module 604 is used to adjust the height of the first electrode and the second electrode based on the difference between the arc power and the target power after the arc power has been increased to the target power.

[0145] Optionally, based on the above technical solution, the electrode control module 601 is also used to: adjust the height of the first electrode and the second electrode until they come into contact with the arc-initiating agent covering the secondary hazardous waste in the melting furnace.

[0146] Optionally, based on the above technical solution, the electrode control module 601 includes:

[0147] Torque acquisition unit, used to acquire the torque values ​​of the first electrode clamping part and the second electrode clamping part;

[0148] An electrode control unit is configured to lower the height of the first electrode and the second electrode when the torque value of the first electrode clamping part or the second electrode clamping part is less than a preset torque value.

[0149] When the torque value of the first electrode clamping part or the second electrode clamping part is equal to the preset torque value, the adjustment of the height of the first electrode and the second electrode is stopped.

[0150] When the torque value of the first electrode clamping part or the second electrode clamping part is greater than the preset torque value, the height of the first electrode and the second electrode is raised.

[0151] Optionally, based on the above technical solution, the control device 600 further includes:

[0152] Voltage detection module, used to monitor arc voltage;

[0153] The arc ignition judgment module is used to determine that arc ignition has failed if the arc voltage is greater than the upper limit of the safe voltage or less than the lower limit of the safe voltage; and to determine that arc ignition has succeeded if the arc voltage is neither greater than the upper limit of the safe voltage nor less than the lower limit of the safe voltage.

[0154] Optionally, based on the above technical solution, the arc ignition judgment module is also used to: if the arc voltage at a certain moment is greater than the upper limit of the safe voltage or less than the lower limit of the safe voltage, it is considered that the arc ignition has failed.

[0155] Optionally, based on the above technical solution, the arc ignition judgment module is also used to: if the arc voltage is not greater than the upper limit of the safe voltage and the arc voltage is greater than or less than the lower limit of the safe voltage within a preset time, the arc ignition is considered successful.

[0156] Optionally, based on the above technical solution, the control device 600 further includes:

[0157] The temperature acquisition unit is used to acquire the furnace temperature if arc ignition fails.

[0158] The adjustment unit is used to adjust the output current of the constant current source or to add an arc-initiating agent to the surface of the secondary hazardous waste based on the furnace temperature.

[0159] The arc-starting unit is used to restart the constant current source mentioned above in an attempt to start an arc.

[0160] Optionally, based on the above technical solution, the adjustment unit further includes:

[0161] The first current adjustment unit is used to adjust the output current of the constant current source if the furnace temperature is higher than or equal to the first preset temperature.

[0162] An arc-initiating agent adjustment unit is used to add arc-initiating agent to the surface of the aforementioned secondary hazardous waste if the furnace temperature is lower than the first preset temperature.

[0163] Optionally, based on the above technical solution, the temperature control module 602 further includes:

[0164] The voltage monitoring unit is used to maintain the above output current unchanged and monitor the arc voltage after successful arc ignition;

[0165] The first temperature control unit adjusts the output current based on the furnace temperature if the arc voltage drops to the lower limit of the safe voltage, or if the arc voltage no longer drops within the first time interval and is less than the upper limit of the safe voltage; wherein the lower limit of the safe voltage is the minimum voltage to maintain the arc, and the upper limit of the safe voltage is the maximum voltage to maintain the arc.

[0166] Optionally, based on the above technical solution, the first temperature control unit further includes:

[0167] The temperature change curve acquisition unit is used to acquire a preset temperature change curve; wherein, the preset temperature change curve is related to the characteristics of the refractory material in the electric arc melting furnace.

[0168] The second temperature control unit is used to adjust the output current based on the furnace temperature and the preset temperature change curve.

[0169] Optionally, based on the above technical solution, the second temperature control unit is further used for:

[0170] Get the furnace temperature at the current time point;

[0171] Based on the furnace temperature at the current time point, determine whether there is a corresponding point on the preset temperature change curve; wherein, the temperature value of the preset temperature change curve at the corresponding point is equal to the furnace temperature at the current time point.

[0172] If the above-mentioned preset temperature change curve has a corresponding point, the above-mentioned corresponding point shall be used as the first reference point;

[0173] Based on the current time point mentioned above, the furnace temperature after a preset second time interval is obtained and determined as the first actual temperature;

[0174] Based on the aforementioned preset temperature change curve, the aforementioned first reference point, and the aforementioned preset second time interval, the aforementioned second reference point is determined;

[0175] The temperature corresponding to the second reference point mentioned above is determined as the first target temperature;

[0176] Based on the aforementioned first actual temperature and the aforementioned first target temperature, adjust the output current.

[0177] Optionally, based on the above technical solution, the second temperature control unit is further used for:

[0178] The first actual temperature and the first target temperature are input into the PID proportional-integral-derivative module to obtain the output result;

[0179] Based on the above output results, determine the adjusted output current.

[0180] Optionally, based on the above technical solution, the second temperature control unit is further configured to: determine the difference between the first actual temperature and the first target temperature;

[0181] Based on the difference between the first actual temperature and the first target temperature, the adjusted output current is determined.

[0182] Optionally, based on the above technical solution, the control device 600 further includes:

[0183] The first image acquisition module is used to acquire a first image, which is an image of the surface of the secondary hazardous waste inside the melting furnace.

[0184] The first determining module is used to determine the reflected light intensity or reflectivity of the secondary hazardous waste based on the first image.

[0185] The first electrode adjustment module is used to lower the height of the first electrode and the second electrode when the intensity of the reflected light is greater than a predetermined light intensity value or the reflectivity is greater than a predetermined reflectivity; and to stop adjusting the height of the first electrode and the second electrode if the torque value of the first electrode clamping part or the second electrode clamping part is greater than or equal to a preset torque value.

[0186] Optionally, based on the above technical solution, the control device 600 further includes:

[0187] The second image acquisition module is used to acquire a second image; wherein the second image includes a first electrode, a second electrode, and at least a portion of secondary hazardous waste;

[0188] The second electrode detection module is used to identify the first electrode and the second electrode based on the second image described above.

[0189] The texture feature determination module is used to determine the texture features of the adjacent regions of the first electrode and the second electrode.

[0190] The texture uniformity determination module is used to determine the texture uniformity of the adjacent regions based on the texture features described above.

[0191] The second electrode adjustment module is used to reduce the height of the first electrode and the second electrode when the texture uniformity of the adjacent areas is greater than a predetermined value; and to stop adjusting the height of the first electrode and the second electrode if the torque value of the first electrode clamping part or the second electrode clamping part is greater than or equal to a preset torque value.

[0192] Optionally, based on the above technical solution, the power control module 603 further includes:

[0193] The second current adjustment unit is used to adjust the output current based on a preset increment if the furnace temperature is greater than the second preset temperature.

[0194] The second electrode adjustment unit is used to reduce the height of the first and second electrodes if the arc voltage is greater than or equal to the upper limit of the safe voltage.

[0195] Optionally, based on the above technical solution, the power control module 603 further includes:

[0196] The third current adjustment unit is used to adjust the output current based on a preset increment if the furnace temperature is greater than the second preset temperature.

[0197] The power determination unit is used to determine whether the arc power is greater than or equal to the target power after the third time interval.

[0198] The third electrode adjustment unit is used to adjust the output current again based on a preset increment if the arc power is less than the target power.

[0199] Optionally, based on the above technical solution, the power stabilization module 604 is used to: if the difference between the arc power and the target power is greater than 0, reduce the height of the first electrode and the second electrode.

[0200] If the difference between the arc power and the target power is less than 0, the height of the first electrode and the second electrode is increased.

[0201] Optionally, based on the above technical solution, the power stabilization module 604 is used to: when the difference between the arc power and the target power is greater than 0, determine whether the torque value of the first electrode clamping part or the second electrode clamping part is greater than or equal to a preset torque value.

[0202] When the torque value of the first electrode clamping part or the second electrode clamping part is greater than or equal to the preset torque value, the output current is reduced.

[0203] This disclosure proposes a control device for a plasma arc melting furnace. On one hand, by covering the surface of secondary hazardous waste with an arc-initiating agent, the discharge distance between electrodes is prevented from failing to meet requirements due to the insulating properties of the hazardous waste, thus improving the arc ignition success rate. Compared with existing technologies that rely on other heat sources, this reduces operational difficulty and lowers equipment and operating costs. On the other hand, a constant current source replaces the constant voltage source commonly used in existing plasma arc melting furnaces. The current is controlled by adjusting the output current of the constant current source, and the contact area between the electrodes and the furnace material is changed by adjusting the height of the first and second electrodes, thereby indirectly controlling the arc voltage. Selective control of both at different stages maintains a constant output power. On the other hand, adjusting the output current of the constant current source can indirectly control the furnace temperature. During the heating stage after successful arc ignition, the output current is adjusted based on the arc voltage and furnace temperature, preventing arc interruption caused by abnormal arc voltage while simultaneously increasing the temperature.

[0204] Figure 7 This is a schematic diagram of the structure of an electronic device provided as an exemplary embodiment of this disclosure. For example... Figure 7 As shown, the electronic device 700 includes at least one processor 701 and a memory 702 coupled to the processor 701. The processor 701 can perform the corresponding steps in the methods disclosed in the embodiments of this disclosure.

[0205] The processor 701 described above can also be called a central processing unit (CPU), which can be an integrated circuit chip with signal processing capabilities. Each step in the method disclosed in this embodiment can be implemented by the integrated logic circuitry in the processor 701 or by software instructions. The processor 701 can be a general-purpose processor, a digital signal processor (DSP), an ASIC, a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this embodiment can be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software modules can be located in the memory 702, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The processor 701 reads information from the memory 702 and, in conjunction with its hardware, completes the steps of the method described above.

[0206] Furthermore, various operations / processes according to this disclosure, implemented via software and / or firmware, can be transmitted from a storage medium or network to a computer system with a dedicated hardware architecture, such as... Figure 8 The computer system 800 shown is equipped with the programs that constitute the software. When various programs are installed, the computer system is able to perform various functions, including those mentioned above. Figure 8 A block diagram of a computer system provided for an exemplary embodiment of this disclosure.

[0207] Computer system 800 is intended to represent various forms of digital electronic computer devices, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. Electronic devices may also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the present disclosure described and / or claimed herein.

[0208] like Figure 8 As shown, the computer system 800 includes a computing unit 801, which can perform various appropriate actions and processes based on a computer program stored in a read-only memory (ROM) 802 or a computer program loaded from a storage unit 808 into a random access memory (RAM) 803. The RAM 803 may also store various programs and data required for the operation of the computer system 800. The computing unit 801, ROM 802, and RAM 803 are interconnected via a bus 804. An input / output (I / O) interface 805 is also connected to the bus 804.

[0209] Multiple components in the computer system 800 are connected to the I / O interface 805, including: an input unit 806, an output unit 807, a storage unit 808, and a communication unit 809. The input unit 806 can be any type of device capable of inputting information into the computer system 800. The input unit 806 can receive input numerical or character information and generate key signal inputs related to user settings and / or function control of the electronic device. The output unit 807 can be any type of device capable of presenting information and may include, but is not limited to, a monitor, speaker, video / audio output terminal, vibrator, and / or printer. The storage unit 808 may include, but is not limited to, a hard disk and an optical disk. The communication unit 809 allows the computer system 800 to exchange information / data with other devices via a network such as the Internet, and may include, but is not limited to, a modem, network card, infrared communication device, wireless communication transceiver, and / or chipset, such as Bluetooth™ device, WiFi device, WiMax device, cellular communication device, and / or the like.

[0210] The computing unit 801 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 801 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The computing unit 801 performs the various methods and processes described above. For example, in some embodiments, the methods disclosed in this disclosure can be implemented as a computer software program tangibly contained in a machine-readable medium, such as storage unit 808. In some embodiments, part or all of the computer program can be loaded and / or installed on the computer system 800 via ROM 802 and / or communication unit 809. In some embodiments, the computing unit 801 can be configured to perform the methods disclosed in this disclosure by any other suitable means (e.g., by means of firmware).

[0211] This disclosure also provides a computer-readable storage medium, wherein when the instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device is able to perform the methods disclosed in this disclosure.

[0212] The computer-readable storage medium in this disclosure can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. The aforementioned computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specifically, the aforementioned computer-readable storage medium may include electrical connections based on one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0213] The aforementioned computer-readable medium may be included in the aforementioned electronic device; or it may exist independently and not assembled into the electronic device.

[0214] This disclosure also provides a computer program product, including a computer program, wherein when the computer program is executed by a processor, it implements the methods disclosed in this disclosure.

[0215] In embodiments of this disclosure, computer program code for performing the operations of this disclosure can be written in one or more programming languages ​​or a combination thereof. These programming languages ​​include, but are not limited to, object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network (including a local area network (LAN) or a wide area network (WAN)), or it can be connected to an external computer.

[0216] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0217] The modules, components, or units described in the embodiments of this disclosure can be implemented in software or hardware. The names of the modules, components, or units do not necessarily constitute a limitation on the module, component, or unit itself.

[0218] The functions described above in this document can be performed at least in part by one or more hardware logic components. For example, without limitation, exemplary hardware logic components that can be used include: field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), system-on-a-chip (SoCs), complex programmable logic devices (CPLDs), and so on.

[0219] The above description is merely an embodiment of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features disclosed in this disclosure that have similar functions.

[0220] While specific embodiments of this disclosure have been described in detail by way of example, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of this disclosure. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this disclosure. The scope of this disclosure is defined by the appended claims.

Claims

1. A control method for a plasma arc melting furnace, characterized in that: The melting furnace is used to treat secondary hazardous waste. The melting furnace includes a constant current source, a first electrode, and a second electrode. The constant current source is connected to the first electrode and the second electrode, respectively. The output current of the constant current source is introduced into the furnace through the electrodes. The method includes: The heights of the first and second electrodes are adjusted until they come into contact with the secondary hazardous waste inside the melting furnace; wherein the surface of the secondary hazardous waste is covered with an arc-initiating agent; After successful arc ignition, the output current of the constant current source is adjusted based on the arc voltage and furnace temperature. If the furnace temperature is greater than the second preset temperature, the output current is adjusted based on the preset increment to increase the arc power; wherein, the second preset temperature is greater than or equal to the melting point of the secondary hazardous waste, and the preset increment depends on the maximum value of the output current of the constant current source; After the arc power is raised to the target power, the height of the first electrode and the second electrode is adjusted based on the difference between the arc power and the target power to keep the arc power constant. After successful arc ignition, the output current of the constant current source is adjusted based on the arc voltage and furnace temperature, including: After successful arc ignition, maintain the output current constant and monitor the arc voltage; If the arc voltage drops to the lower limit of the safe voltage, or if the arc voltage no longer drops within the first time interval and is less than the upper limit of the safe voltage, the output current is adjusted based on the furnace temperature; wherein, the lower limit of the safe voltage is the minimum voltage required to maintain the arc, and the upper limit of the safe voltage is the maximum voltage required to maintain the arc; The adjustment of the output current based on the furnace temperature includes: Obtain a preset temperature change curve; wherein, the preset temperature change curve is related to the characteristics of the refractory material in the plasma arc melting furnace; The output current is adjusted based on the furnace temperature and the preset temperature change curve.

2. The method according to claim 1, characterized in that, The melting furnace further includes a first electrode clamping part and a second electrode clamping part, wherein the first electrode clamping part is used to clamp the first electrode and the second electrode clamping part is used to clamp the second electrode; Adjusting the height of the first and second electrodes until they contact the secondary hazardous waste inside the melting furnace includes: Obtain the torque values ​​of the first electrode clamping part and the second electrode clamping part; When the torque value of the first electrode clamping part or the second electrode clamping part is less than the preset torque value, the height of the first electrode and the second electrode is reduced. When the torque value of the first electrode clamping part or the second electrode clamping part is equal to the preset torque value, stop adjusting the height of the first electrode and the second electrode; When the torque value of the first electrode clamping part or the second electrode clamping part is greater than the preset torque value, the height of the first electrode and the second electrode is raised.

3. The method according to claim 1, characterized in that, Based on the furnace temperature and the preset temperature change curve, the output current is adjusted, including: Get the furnace temperature at the current time point; Based on the furnace temperature at the current time point, determine whether the preset temperature change curve has a corresponding point; wherein, the temperature value of the preset temperature change curve at the corresponding point is equal to the furnace temperature at the current time point; If the preset temperature change curve has a corresponding point, the corresponding point shall be used as the first reference point; Based on the current time point, the furnace temperature after a preset second time interval is obtained and determined as the first actual temperature; The second reference point is determined based on the preset temperature change curve, the first reference point, and the preset second time interval; The temperature corresponding to the second reference point is determined as the first target temperature; The output current is adjusted based on the first actual temperature and the first target temperature.

4. The method according to claim 1, characterized in that, If the furnace temperature is greater than the second preset temperature, the output current is adjusted based on a preset increment, and then the process further includes: If the arc voltage is greater than or equal to the upper limit of the safe voltage, reduce the height of the first electrode and the second electrode.

5. The method according to claim 1, characterized in that, Adjusting the height of the first and second electrodes based on the difference between the arc power and the target power includes: If the difference between the arc power and the target power is greater than 0, reduce the height of the first electrode and the second electrode; If the difference between the arc power and the target power is less than 0, the height of the first electrode and the second electrode is increased.

6. A control device for a plasma arc melting furnace, characterized in that, The melting furnace is used to treat secondary hazardous waste. The melting furnace includes a constant current source, a first electrode, and a second electrode. The constant current source is connected to the first electrode and the second electrode, respectively. The output current of the constant current source is introduced into the furnace through the electrodes. The control device is used to implement the control method as described in any one of claims 1-5. The device includes: An electrode control module is used to adjust the height of the first electrode and the second electrode until they come into contact with the secondary hazardous waste inside the melting furnace; wherein the surface of the secondary hazardous waste is covered with an arc-initiating agent; The temperature control module is used to adjust the output current of the constant current source based on the arc voltage and the furnace temperature after successful arc ignition. A power control module is used to adjust the output current based on a preset increment to increase the arc power if the furnace temperature is greater than a second preset temperature; wherein the second preset temperature is greater than or equal to the melting point of the secondary hazardous waste. A power stabilization module is used to adjust the height of the first electrode and the second electrode based on the difference between the arc power and the target power after the arc power has risen to the target power, so as to keep the arc power constant.

7. An electronic device, characterized in that, include: At least one processor; Memory for storing the at least one processor-executable instruction; The at least one processor is configured to execute the instructions to implement the method as described in any one of claims 1-5.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method as described in any one of claims 1-5.

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