Study of Calcium Ferrite as an Alternate Source of Iron in BOF

Abstract

In conventional process of steelmaking, limestone and scrap are generally used in BOF for slagging and to act as a source of iron respectively. Apart from being an iron source, scrap also functions as a coolant. However, the formation of 2CaO.SiO2 on the surface of lime during the dissolution process results in slower slagging speeds. In the present work, calcium ferrite has been studied as a source of iron which can simultaneously replace the scrap and lime addition. The reduction of FeOx in CF by carbon in Fe-C-Si melt can not only give iron content but also the coolant effect due to the endothermic nature of reaction. Further, presence of CaO in dissolved form would also eliminate the problem of slow lime dissolution. Thermodynamic calculations using FactSage program have been done to find the optimum composition, pre-reduction and also heat balance with the conventional process. Experiments have been performed to study the reduction of calcium ferrites using various reducing agents to analyze the reduction behavior and generation of iron.