Co-wetting behavior of molten slag and iron on carbon materials in blast furnace

Abstract

The interaction between molten slag, liquid iron, and carbon is one of the most typical and complex multiphase flow behaviors in the high-temperature zone of blast furnace. The wetting behavior among these phases is the most fundamental characteristic that determines their interactions. This research focuses on the co-wetting behavior of molten slag and iron on graphite, using high-temperature experiments and atomistic simulations. The results revealed that the multiphase cooperative reaction wetting process is influenced by multiple factors. The wettability of molten iron is mainly affected by its initial carbon content, while the wettability of slag is influenced by both the initial carbon content of the molten iron and its own compositional changes. The initial carbon content in molten iron affects the carburizing reaction, which in turn influences the wetting mechanism between molten iron and graphite. Additionally, it alters the reaction of FeO in the slag, thereby modifying the properties of the slag-carbon interface and affecting the overall co-wetting process. Meta-dynamic calculations showed that the reduction of molten iron oxide by dissolved carbon is significantly more effective than that by solid graphite carbon, demonstrating that the behavior of carbon between iron and slag is a key factor in the multiphase cooperative reaction process.