Observation on Reaction Mechanism of Lime Powder as Desulfurization Agent for Molten Cast Iron

This study investigates the reaction mechanism between lime powder and molten cast iron as a sustainable alternative desulfurization agent for the cast iron industry. The approach involved metallography and chemical analysis of the slag that emerged from a laboratory‐scale lime‐based desulfurization process conducted in inert and open‐atmospheric treatments. The observation results indicate that the applicability of the lime‐based desulfurization process in cast iron depends mainly on the existence of liquid phases composed of a specific liquid slag configuration. This slag facilitates the interaction between lime and sulfur, thus sustaining desulfurization. This study also elucidates that distinguishable structures construct the reaction layer formed by a particular proportion of slag systems comprising specific compositions of calcium, silicon, aluminum, iron, and sulfur. This study establishes a foundation for advancing sustainable practices within the cast iron and steel industries by promoting an understanding of these fundamental mechanisms.