Development and Optimization of Ferrochrome Production Using Pre-Reduced Chromite Pellets

This study investigates the production of high-carbon ferrochrome (HCFeCr) using pre-reduced chromite pellets. Chromite ore from the Kempirsai deposit, semicoke as a reducing agent, and activated bentonite as a binder were used for pellet preparation. Pellets with a size of 12-14 mm were produced and subjected to reduction roasting at 1400 °C for 1-3 h. The results showed that increasing the roasting time promoted chromite reduction and increased the chromium metallization degree. After 3 h of roasting, the chromium metallization degree reached 43.93%. SEM analysis confirmed the formation of metallized chromium-containing phases and a porous structure favorable for subsequent smelting. Smelting experiments were carried out in a 0.1 MVA ore-thermal furnace using pre-reduced pellets. Stable furnace operation, satisfactory slag fluidity, and effective separation of metal and slag were observed. The obtained high-carbon ferrochrome contained 68.92 wt.% Cr, 1.54 wt.% Si, and 7.11 wt.% C. Chromium recovery into the alloy reached 92.17%, while the slag contained 2.14 wt.% Cr₂O₃. The specific electric energy consumption during experimental smelting was 4648.1 kWh/t of ferrochrome. Recalculation to industrial conditions showed an expected energy consumption of 3132.76 kWh/t, confirming the potential of pre-reduced chromite pellets for energy-efficient ferrochrome production.