Investigation of Fe–Mn particle aggregation and growth processes in molten slag

Abstract

ABSTRACTThe aggregation and growth behaviours of Fe–Mn particles in the direct alloying process were investigated using the high-temperature experiment. The manganese-rich slag was used as a source of manganese to make into the briquette for the alloying process, and the quaternary slag was prepared using an analytical reagent. To monitor the aggregation and growth process of metal particles and its chemical reactions, some test methods, such as XRD, TDA SEM and EDS, were applied. The results showed that after the briquette is added into the melted slag, because the heat is transferred from the outer layer of the briquette to its interior, the growth process of metal particles can be divided into three stages: nucleation period, aggregation period and growth period. In the first two stages, the Fe particles are first reduced as the nucleation for the alloying process, while the Mn particles are nucleated by Fe particles and formed Fe–Mn particles. Finally, the Fe–Mn particles gradually grow up. In addition, the statistical model was developed for describing the growth process of Fe–Mn particle, and it shows a good relationship with the measured value.