氧气转炉采用石灰石造渣炼钢铁水中硅挥发的分析

Analysis of Si volatilization during the BOF steelmaking process using limestone for slagging

摘要: 对转炉采用石灰石造渣炼钢引起硅挥发的原因进行了分析，通过热力学计算得到了高碳低温铁水面上SiO稳定存在的温度及气氛条件.分析结果表明，标准状态下，铁水中各元素与CO₂的氧化反应中，SiO生成反应只在火点区附近可以进行；温度为1400~2300 K时，使得SiO稳定存在的p_CO/p_CO₂随温度升高逐渐降低，该气氛条件相当于p_O₂在10^-25~10^-13数量级；在2 min内加入石灰石的条件下，Si挥发时的p_SiO大致在10^-2数量级，与实际生产中大致相同.

Abstract: The reason of Si volatilization during the BOF steelmaking process using limestone for slagging was analyzed. After thermodynamic calculation,the temperature and atmosphere conditions that SiO exists stably near the surface of molten iron with high carbon concentration and low temperature were obtained. Results show that the SiO generation reaction only takes place in the "fire zone" in oxidation reactions between some elements in molten iron and CO₂. At the temperature of 1400 to 2300 K,the value of p_CO/p_CO₂ that makes SiO exist stably decreases gradually with the increase of temperature,which equals to 10^-25~10^-13 magnitude of the partial pressure of oxygen. Under the condition of adding limestone in 2 min,the partial pressure of SiO is about 10^-2 magnitude whenSivolatilizes,which is consistent with the practical production.