Critical Evaluation of Prediction Models for Phosphorus Partition between CaO-based Slags and Iron-based Melts during Dephosphorization Processes

According to the experimental results of hot metal dephosphorization by CaO-based slags at a commercial-scale hot metal pretreatment station, the collected 16 models of equilibrium quotient or phosphorus partition between CaO-based slags and iron-based melts from the literature have been evaluated. The collected 16 models for predicting equilibrium quotient can be transferred to predict phosphorus partition . The predicted results by the collected 16 models cannot be applied to be criteria for evaluating or due to various forms or definitions of or . Thus, the measured phosphorus content [pct P] in a hot metal bath at the end point of the dephosphorization pretreatment process is applied to be the fixed criteria for evaluating the collected 16 models. The collected 16 models can be described in the form of linear functions as , in which independent variable represents the chemical composition of slags, intercept including the constant term depicts the temperature effect and other unmentioned or acquiescent thermodynamic factors, and slope is regressed by the experimental results of or . Thus, a general approach to developing the thermodynamic model for predicting equilibrium quotient or phosphorus partition L (P) or [pct P] in iron-based melts during the dephosphorization process is proposed by revising the constant term in intercept for the summarized 15 models except for Suito's model (M3). The better models with an ideal revising possibility or flexibility among the collected 16 models have been selected and recommended. Compared with the predicted result by the revised 15 models and Suito's model (M3), the developed IMCT- model coupled with the proposed dephosphorization mechanism by the present authors can be applied to accurately predict phosphorus partition with the lowest mean deviation of as 2.33, as well as to predict [pct P] in a hot metal bath with the smallest mean deviation of [pct P] as 12.31.