Kinetic Study of Dephosphorization of Liquid Iron with Oxidizing Slag

Abstract

A kinetic study is made of dephosphorization reaction of liquid iron-phosphorus alloy with steelmaking slag in laboratory scale. Iron-phosphorus alloys and CaO-FeO-Si0₂ system slags are melted in fused MgO crucible at 1550°C and 1600°C in resistance furnace.
The results presented here are summarized as follows.
1) The dephosphorization reaction is first order reaction with chemical reaction controll.
2) The dephosphorization rate constants are variable with slag composition and it is considered that the optimum slag composition for dephosphorization is the “nose” composition of liquidus line of 2CaOSiO₂in the phase diagram of CaO-FeO-SiO₂ system.