Approaches for Conversion of High Phosphorus Hot Metal to Steel for Flat Products

Consistent production of low phosphorus steel (≤0.015%) from high hot metal phosphorus (~0.230%) in BOF steelmaking is a technologically challenging task. The problem gets compounded if steel is to be tapped at high temperature (≥1700°C).This paper deals with the continuing efforts and experiences of producing low phosphorus steel at steel melting shop no. 2. Two approaches are mentioned. First approach being optimization of slag chilling process near the blow end which has enabled better control of steel phosphorus in high temperature heats. Other approach delves into an extensive data mining study to understand dephosphorization behaviour in BOF. Data mining throws few interesting findings based on which underlying mechanism of BOF dephosphorization has been proposed.