Development of a model for calculating additions in the Slag Splashing and Slag Coating process of a Basic Oxygen Furnace (BOF)

Nowadays, most of steelworks based on BOF (Basic Oxygen Furnace) use the slag splashing technique to increase the availability of their assets (BOF) due to an increase at refractory lining campaign. Although slag splashing technique has more than 30 years and slag coating technique has more than 60 years, it is possible to improve the results if actions are correctly applied to adjust the slag to the boundary conditions of each steelmaking plant. This work is aimed at evaluating the influence of slag properties (viscosity and phase distribution) on the slag splashing and slag coating practices. In this way, one can optimize operational conditions, so that these techniques can be applied more efficiently, ensuring the best practice regarding the formation of a protective coating that helps to decrease wear of refractory lining. Initially, slag samples have been characterized through XRD (X-ray diffraction) analysis, and thermodynamic simulations were carried out, considering slag compositions before and after the slag splashing practice. A model has been built in order to indicate the correct action to be adopted that allows, as a function of operational conditions, to reduce the wear rate of refractory BOF lining. The results obtained with the model applied lead to the reduction of the wear rate of BOF refractory lining, as well as the needs to apply ramming material for repair. (author)