The bottom-blown furnace uses oxygen lances installed in the furnace bottom to inject oxygen or oxygen-enriched air into the molten bath, agitating the bath and enhancing contact between the gas phase and molten materials. This creates a solid-liquid-gas three-phase reaction system. After oxidation and slag formation, the slag phase separates from the matte, while smelting off-gas is produced.
Refractory lining damage is caused by the combined effects of matte penetration, chemical corrosion from molten slag, and erosion from molten materials and gas flow. Magnesia-chrome bricks with 24%-26% Cr2O3 content are recommended for the oxygen lance area, while magnesia-chrome bricks with 18%-22% Cr2O3 content are used for the remaining furnace body areas.
