METHOD OF REFINING VANADIUM CAST IRONS IN STEELMAKING UNITS Russian patent published in 1998 - IPC

FIELD: ferrous metallurgy, more specifically, refining of vanadium cast iron in steelmaking units. SUBSTANCE: method includes charging the open-hearth furnace, at the first stage of the process, with steel scrap in the amount of 10-18% of weight of liquid vanadium cast iron and heating up to 1300-1350 C. Vanadium cast iron is poured and blown with oxidizing gas through roof lances with flow rate of 1200-1300 cu.m/h for every lance. Upon attainment of melt temperature of 1400 C, coolant-oxidizer is added. Weight of coolant-oxidizer to weight of steel scrap ratio is maintained within (0.08-0.20):1. To improve coming off of vanadium slag, it is heated by means of gas-flame burners. Cooling of melt is discontinued at attainment of vanadium content in metal of not more than 0.03%. Coolant-oxidizer is used in the form of roll scale and/or light scrap. Vanadium slag is flushed. A part of high-temperature slag is left in furnace for heating of steel scrap of ensuing heat. EFFECT: mastered technology of refining vanadium cast irons in open-hearth furnace with production of conditioned vanadium slag. 2 cl