A Mathematical Model for the Reduction Stage of the AOD Process. Part I: Derivation of the Model

A process model was proposed by Jarvinen and co-authors for modelling the side-blowing decarburisation stage of the Argon-Oxygen Decarburisation (AOD) process. Here, a new model for the reduction stage has been derived and coupled with the earlier-developed model. The model considers mass-transfer controlled reversible reactions between the steel bath and the top slag. The effect of emulsification phenomena on the total reaction area and on the mass and heat transfer characteristics have been taken into account. The effects of various additions on the mass and heat balance have also been considered. The paper is divided into two parts: Part I presents the derivation of the model, while Part II considers validation of the model with full-scale production data from a 150 t AOD converter at Outokumpu Stainless Oy, Tornio Works, Finland.