The kinetics of reoxidation of Al killed steel with slag and air were investigated in laboratory experiments using tammann furnace and in plant experiments using commercial 85×103 kg tundish. Experimental results were discussed by the coupled reaction model.
Observed apparent rate constants of [sol.Al] decreased with increasing (CaO)/(SiO2) ratio in laboratory experiments and showed a good agreement with calculated ones.
Flow rate of air leak at steady state was evaluated to be 3.0×10-5 and 4.0×10-4 m3/s inside and outside of immersion tube in commercial tundish, respectively and was estimated to have little influence on reoxidation.
Mass transfer coefficient in metal was estimated to be 6.0×10-5 m/s based on the tundish mixing model and the coupled reaction model.
Observed [sol.Al] in tundish decreased with increasing (%FeO)+(%MnO) value in ladle slag and showed a good agreement with calculated one by considering reoxidation in ladle and air leak at unsteady state.
