Investigation on removal of Nb from Nb-bearing hot metal with CO₂

Abstract

This paper focuses on removal niobium from Nb-bearing hot metal by bottom blown-CO2 gas at flow rate of 1,0×103 Nm3/h, 1,5×10-3 Nm3/h at 1350 °C and 1 450 °C in a medium induction furnace. The results show that Nb and P are oxidized and the ratio of Nb to P in Nb-bearing slag at blowing termination reaches to 46,66 at 1350 °C and CO2 flow rate of 1,5m3/h, which is more than that in the other condition; it improves to remove more Nb from hot metal with bottom-blown CO2 at 1 350 °C than at 1450 °C; Nb starts to oxidize by CO2 to form slag when Si content in molten iron decreases to low 0,1 wt. %.

Keywords

• hot metal
• removal of Nb
• bottom-CO₂
• time
• temperature