氧氣轉爐采用石灰石造渣煉鋼鐵水中硅揮發的分析

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

摘要: 對轉爐采用石灰石造渣煉鋼引起硅揮發的原因進行了分析，通過熱力學計算得到了高碳低溫鐵水面上SiO穩定存在的溫度及氣氛條件.分析結果表明，標準狀態下，鐵水中各元素與CO₂的氧化反應中，SiO生成反應只在火點區附近可以進行；溫度為1400~2300 K時，使得SiO穩定存在的p_CO/p_CO₂隨溫度升高逐漸降低，該氣氛條件相當于p_O₂在10^-25~10^-13數量級；在2 min內加入石灰石的條件下，Si揮發時的p_SiO大致在10^-2數量級，與實際生產中大致相同.

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.