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  Metallurgical electric arc furnace is a steelmaking method that uses the heat effect of electric arc to heat the furnace charge for smelting. The alternating current is input into the furnace through three graphite electrodes, and an electric arc is generated between the lower end of the electrode and the metal material. The high temperature of the electric arc is used to directly heat the furnace material, so that the steel-making process can be carried out. The scrap is the main raw material in EAF steelmaking. According to the different lining materials and slagging materials, there are two kinds of methods: basic method and acid method. The most commonly used method is alkaline method. Electric energy is used as heat source in EAF steelmaking to avoid the pollution of sulfur contained in gas heat source to steel; the operation process is flexible, and the slag and furnace gas can be adjusted to oxidizability or reducibility; strong reducibility can make precious elements such as chromium, nickel, tungsten, molybdenum, vanadium and titanium contained in the furnace charge less burned; high furnace temperature, easy to control; high product quality.