Optical Emission Analysis of Slag Surface Conditions and Furnace Atmosphere during Different Process Stages in Electric Arc Furnace (EAF)

In electric arc furnace (EAF) steelmaking, the process control has traditionally been managed by operators, with current automation levels preventing full dynamic control. This study aimed to enhance process understanding by utilizing an innovative method of on-line in situ optical emission spectroscopy. Optical emission spectra were measured at Outokumpu Stainless Oy's Tornio works over the span of one month, focusing on the analysis of slag surface conditions and alkali emission lines during various process stages. The findings indicate that the optical emission method can provide valuable insights into scrap melting and other critical parameters, thus addressing the limitations of existing measurement techniques. This research contributes to the ongoing efforts to improve automation and dynamic control within EAF systems by facilitating better real-time data on process conditions. The results not only shed light on the slag chemistry and its implications for EAF performance but also suggest pathways for future investigations into advanced monitoring techniques. Overall, this study emphasizes the significance of optimizing the control of EAF operations for enhanced efficiency and quality in steel production.