Regular Article

Study on desulfurization capacity of high alumina blast furnace slag at 1773 K using slag-metal equilibrium technique

Department of Metallurgical and Materials Engineering Rourkela, National Institute of Technology, Rourkela 769008 India

^* e-mail: yedlan@nitrkl.ac.in

Received: 20 April 2017
Accepted: 6 February 2018

Abstract

In the current paper, we have determined the desulfurization ability of a CaO–MgO–SiO₂–Al₂O₃ slag system using slag-metal equilibrium technique. The chemical composition of slag samples consists of Al₂O₃ in the range of 25–30 wt%, CaO/SiO₂ ratio (0.8–1.6) and MgO (8–16 wt%). All the experiments are conducted at a temperature of 1773 K. The sulphur content in the slag as well as in metal after desulfurization reaction is analyzed using XRF (X-ray Fluorescence Spectroscopy) for calculating sulphur partition ratio (L_S) of the slags. The influence of Al₂O₃, CaO/SiO₂ ratio and MgO content on L_S have been studied. It is observed that L_S increase with an increase in CaO/SiO₂ ratio and MgO content, but it reduces as the Al₂O₃ content increase in slag. Also, the amount of bridge oxygen ([BO]) represented by (O⁰) decreases with increase in basicity and MgO content. However, O⁰ increases with increase in Al₂O₃. It is witnessed that the experimental values closely fit with the values obtained from corrected optical basicity model.