A three-phase alternating current transferred arc plasma heating and melting method and system

Abstract

The invention discloses a three-phase alternating current transfer arc plasma heating and melting method and system. The method comprises the following steps: arcing is started between three alternating current arc electrodes and corresponding nozzles, and the gas introduced into the arc chamber is ionized and sprayed to form plasma The flame flow then heats and melts the surface of the material. This step is the pre-melting stage of the non-transfer arc material. After the material surface is pre-melted into a liquid state, the arc root on the nozzle extends to the surface of the pre-melted material, and the arc is converted into a transfer arc form. The three arcs form a closed loop through the material. At this time, under the combined action of plasma flame heat transfer and Joule heat, the material is melted layer by layer from top to bottom. This step is the stage of full melting of the material. The system includes: three AC arc plasma generators with the same structure and a heating and melting furnace. The invention has the advantages of simple power supply system, smaller electrode than ablation, wide application range of materials and high heat transfer efficiency.

Description

technical field [0001] The invention relates to the field of arc plasma heating and melting, in particular to a three-phase alternating current transfer arc plasma heating and melting method and system. Background technique [0002] Arc plasma has the advantages of high temperature, high activity, stable working state, and controllable environment and atmosphere, and has a wide range of applications in the fields of heat treatment or metallurgy. In terms of metallurgy, the temperature of arc plasma can be as high as several thousand or even tens of thousands of degrees Celsius, which can be used for smelting, remelting and recycling or tundish heating of high temperature insoluble metals. This not only improves the chemical reaction rate and shortens the smelting time, but also enables the reaction that is difficult to carry out at room temperature to be realized. In terms of heat treatment, the waste (solid waste, incineration fly ash or furnace ash, medical waste, nuclear...

AI Technical Summary

Problems solved by technology

[0003] At present, in the application process of arc plasma in waste treatment, DC non-transferred arc plasma generators are mostly used to generate high-temperature plasma flames, and the waste and other materials are heated through the plasma flames. Independent, stable operation, but the heat transfer efficiency is relatively low, and the utilization of energy is insufficient; arc plasma is used in metallurgical applications, both transferred arc and non-transferred arc are used, but most of them are DC arcs, which require a configuration structure A complex and costly DC power supply system. In addition, the transferred arc plasma gun is also known as the molten pool heater, which is suitable for melting and heating liquid metal. If the material particle size and bulk density are difficult to meet the requirements, the liquidization of the metal other means of heating are required

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