Decarburization Kinetics of Fe-C-S Droplets with H2O

Abstract

Decarburization of liquid Fe-C-S droplets with H2O vapour was investigated using the electromagnetic levitation technique. The results indicated that the decarburization of liquid iron droplets by H2O vapour can be adequately described by the mixed control of the gas phase mass transport and the dissociative chemisorption of H2O at the melt surface. The Steinberger-Treybal correlation equation was found to correctly represent the gas phase mass transfer in the present system geometry and experimental conditions. The rate of decarburization decreased significantly with increase in sulphur content in the melt, and this effect was quantitatively represented by the mixed control model. There exists a residual rate of decarburization at high sulphur contents in the melt. The extent of the residual rate observed can be interpreted as implying that, even at the melt surface of apparent saturation with sulphur, 8-9% of the surface sites are still available for H2O molecules to react with carbon. The activation energy of dissociative chemisorption of H2O was 95 kJ mol-1. © 1998, The Iron and Steel Institute of Japan. All rights reserved.