METHOD OF LIME PREPARATION FOR STEEL MELTING IN STEELMAKING UNIT Russian patent published in 2020 - IPC C21C5/28 

FIELD: technological processes.

SUBSTANCE: invention relates to a method of preparing lime for steelmaking in a steelmaking unit. Method involves heating and calcination of limestone in a rotating tube furnace, cooling of obtained lime and its supply to steelmaking unit, according to invention for calcination using limestone with total content of manganese of not less than 5 %, which calcination is performed coke oven gas with the heat of combustion of at least 3,000 kcal/m³, a flow rate of 3,500–5,000 m³/hour for at least 1.5 hours, wherein the calcining is carried out at temperatures of 650–700 °C in a hot furnace head and 550–650 °C in cold furnace head, obtained lime is cooled to temperature of not more than 100 °C for not more than 60 minutes. Rotary speed of the tube furnace during lime burning is 1–1.5 rpm. For calcination limestone is used with fractional composition of 40–80 mm.

EFFECT: production of standard high-reaction lime with high content of manganese for further use in out-of-furnace treatment in steel making.

3 cl, 2 tbl