General mass balance for oxygen steelmaking

Mass balances provide a fundamental approach for analysing the oxygen steelmaking process. Steelmaking plants commonly have in-house mass balance models for controlling process parameters. However, there exist only a few details in the literature pertaining to the formulation of such models. Recent research published by Urban et al. [1] surveyed more than 30 BOF around the world and found that the phosphorus partitioning ratio has a strong dependence on oxygen blowing technologies and tapping temperature. The current work develops a general mass balance model using semi-empirical relations that can be used to compute the amount of flux based on the tapping temperature and the desired phosphorus concentration in the steel, applicable for different steelmaking technologies. The static model predictions are presented using a nomogram that illustrates the variation of mass of slag as a function of tapping temperature, silicon content in hot metal and final phosphorus content in the steel.