高炉炉缸区域Ti(C,N)形成条件的热力学分析

为了解含钛铁矿高炉冶炼中Ti(C,N)随物化条件变化的生成规律与分布趋势,引入Ti(C,N)的非理想状态,应用Wagner公式和改进的MIVM(M-MIVM)计算了Ti在碳饱和的Fe-C-Ti熔体中的溶解度。研究了Ti(C,N)从Al_2O_3-CaO-SiO_2-TiO_2熔渣中形成的临界条件及其影响因素。结果显示,在引入Ti(C,N)的非理想状态后,Ti在碳饱和Fe-C-Ti熔体中的溶解度、从熔渣中生成Ti(C,N)固溶体TiO_2平衡含量的计算值均与实验数据吻合良好,计算效果均优于前期的研究;在高炉冶炼过程中,适当降低炉缸区域的温度、提高炉渣碱度、降低渣中Al_2O_3含量、提高炉气总压、降低氮气分压均可抑制碳氮化物的生成;所设计的相平衡研究方法合理可行。研究可为含钛物料高炉冶炼的基础理论研究提供一定的参考。

Thermodynamic analysis of Ti(C,N) formation conditions in blast furnace hearth

In order to understand the formation rule and distribution trend of Ti(C,N) with the change of physicochemical conditions in the smelting of ilmenite in blast furnace, and then considering the fact that titanium carbonitride is a non-ideal solid solution, the solubility of Ti in carbon saturated Fe-C-Ti melt was calculated by Wagner formula and modified MIVM (M-MIVM), and the critical conditions and influencing factors for the formation of Ti(C,N) from Al2O3-CaO-SiO2-TiO2 slag were studied. The results show that the solubility of Ti in carbon saturated Fe-C-Ti melt and the equilibrium content of TiO2 which forms Ti(C,N) solid solution from slag are in good agreement with the experimental data, and the calculation results are better than the previous research. In the process of blast furnace smelting, the formation of carbonitrides can be inhibited by appropriately reducing the temperature of hearth area, increasing the basicity of slag, reducing the content of Al2O3 in slag, increasing the total pressure of furnace gas and reducing the partial pressure of nitrogen. The results show that the method is reasonable and feasible. This study can provide some reference for the basic theoretical research of titanium bearing material smelting in blast furnace.