Dissection Investigation of Ti(C,N) Behavior in Blast Furnace Hearth during Vanadium Titano-magnetite Smelting

This paper presents a comprehensive study on the behaviors of titanium compounds generated in the blast furnace (BF) hearth during the vanadium titano-magnetite smelting by the dissection method combined with experimental and theoretical analysis. The results show that considerable titanium compounds are formed in the eroded furnace wall below the taphole level. The phases of titanium compounds consist of Ti(C,N) crystals, slag phase and liquid iron. The phase of Ti(C,N) crystals are mainly TiCa3N0.7. The formation mechanism of titanium compounds is revealed. It is found that the Ti(C,N) phase is formed within hot metal, while the slag phase originates from the interaction between the mineral in coke and final slag in the BF hearth. Furthermore, the slag is confirmed present in the low part of the BF hearth. The thermal conductivity of the titanium compounds in the hearth is determined as 11.98 W/m/K by analyzing the thermodynamic and heat transfer characteristics of the compounds. This prediction is in satisfactory agreement with the measurement.