石灰石在转炉中与铁水相互作用研究

根据热力学基础理论研究了CO2-CO气体与Fe—C—Si—Mn体系之间反应以及铁水中C]对Ca-CO3分解温度的影响．结果表明，在气氛组成变化很宽的范围内，CO2与C]、Si]、Mn]、Fe（1）反应的AG小于零，石灰石分解产生的部分CO：可以替代氧气参与熔池的氧化．气氛组成影响CO：对铁水中元素的氧化顺序．CO：浓度高CO浓度低时，CO2优先氧化C]；CO2浓度低CO浓度高时，CO2优先氧化Si]．在wC]=2％～4．5％的范围内，石灰石分解温度T与wC]％的关系为T=2．40wC]2%-35．91wC]%＋1129．1．将石灰石煅烧过程从传统石灰窑中转移到转炉可显著降低石灰石分解温度．CaCO3的分解反应和CO2对熔池的氧化反应互相促进，有利于石灰石的分解和铁水中杂质元素的氧化去除．

Interaction between limestone and hot metal in the early stage of BOF steelmaking

Reactions between CO2 - CO gas and Fe - C - Si - Mn melt as well as influence of C] on decomposition temperature of limestone were studied by thermodynamic analysis. The results showed that AG of reactions among CO2 and C ], Si], Mn], Fe （1） are less than zero when gas composition varies in a wide range, indicating part of CO2 from limestone is able to replace oxygen for bath oxidation. The oxidation order of elements in hot metal by CO2 varies with gas composition. Si ] oxidation is prior when CO2 concentration is low while C] oxidation is prior when CO2 concentration is high. kelation between hmestone decomposition temperature and w C] % can be represented as T = 2. 40 w C ] 2% - 35.91w C ] % ＋ 1129. 1 when w C ] = 2% - 4. 5%. If the decomposition process of limestone is transferred from the limekiln to BOF, the decomposition temperature of limestone will drop notably. Interaction between CaCO3 decomposition and bath oxidation by CO2 promotes each other and is beneficial to both decomposition of CaCO3 and removal of impurities from the bath.