Experiment of Phosphorus and Oxygen Distribution between CaO-SiO₂ MgO-Fe_tO Slag and Liquid Steel and Estimation of Phosphorus Content at End Point of Top and Bottom Blowing Converter

Abstract

The phosphorus and oxygen distribution between CaO-SiO₂-Fe_tO slag and molten steel has been obtained in the temperature range from 1 600 to 1 700°C. They can be expressed by the following equations.
log[(%P₂O₅)/{[%P]²(%Fe_tO)⁵}]=11.20 log {(%CaO)+0.3(%MgO)-0.05(%Fe_tO)} +29 600/T-36.25 (i)
log(γ_FetO) =0.0257(%SiO₂)-0.300 (ii)
It has become clear that phosphorus and oxygen distribution between slag and molten steel at end point of 250t top and bottom blowing converter has attained equilibrium by investigating the data at end point on the basis of equations (i) and (ii). Solving the phosphorus distribution equilibrium and the mass balance equations has made it possible to estimate phosphorus content at end point with high accuracy.