STEEL-MAKING METHOD IN ARC-FURNACE Russian patent published in 2008 - IPC C21C5/52 

FIELD: metallurgy.

SUBSTANCE: invitation concerns ferrous metallurgy. Particularly it concerns steel-making method in arc-furnace. Method includes feeding in furnace scrap metal in amount 30-85% and hot metal in amount 15-70% of charge mass, melting, oxidative period. Melt is discharged into casting ladle with leaving of slag and metal portion in furnace. During melt discharging it is implemented feeding into casting ladle of solid slag-forming compound, deoxidising and alloying agent. Into left in furnace slag and metal portion it is added silicon-containing materials at a rate of 0.32-1.63 kg or aluminum-bearing materials at a rate of 0.42-2.15 kg of aluminum or its mixture at a rate of 1:1.32 at a rate of 0.37-1.89 kg silicium and aluminum per tonne of metal rest in furnace. It is implemented burning by oxygen gas with consumption 80-120 m³/h per tonne of metal charge till carbon content not less 0.10% and temperature not more than 1700°C. Into casting ladle while discharging it is added manganiferous alloys at a rate of manganese conduction to the lower limit in finished steel content and lime at a rate of 3-12 kg/t of liquid steel. Steel dressing is implemented on aggregate ladle-furnace.

EFFECT: reducing of steel melting duration.