On the possibility of improving the energy balance of melting in electric arc furnaces

Abstract

This paper is devoted to analyzing the possibility of recovering a portion of the electrical energy consumed during metal melting in electric furnaces, specifically, in electric arc furnaces. It is known that metal melting in electric furnaces (especially in electric arc furnaces) produces a significant amount of dust and gases with high temperatures. The output of gases and their composition depends on the composition of the charge, the melting rate of the technological and temperature modes of melting, the oxygen purge mode, etc. Electric arc furnace production is characterized by the content of fine dust in the furnace exhaust gases, which is released most of all during oxygen purging. The other side of the matter is heat emissions into the environment. Global warming requires a quick and effective solution to this problem. The use of heat from the melting space of electric furnaces can, firstly, save energy resources for in-situ technological purposes, and, secondly, provide hot water, steam, and electricity to both external industrial and domestic consumers. One of the most promising methods of utilizing this heat is the use of thermoelectric phenomena, in particular, the Seebeck effect. Equipment based on this effect allows converting thermal energy into electrical energy, and this can be used to improve the energy efficiency of production. This paper analyzes the theoretical basis for the use of thermoelectric converters in general and for the utilization of heat from waste gases from melting furnaces in particular. Based on the best practices, the electrical power of the converter unit is calculated, and a schematic view of the connection of thermoelectric converters to the power grid and their wiring scheme is presented