1991 Volume 31 Issue 11 Pages 1329-1335
In order to apply a coupled reaction model to the simulation of industrial scale hot metal pretreatment process, a new computer program of MACSIM (Mathematical Analysis Codes for Slag-metal Reaction and Injection Metallurgy) has been developed. In this program, the reactions by injected flux, slag on bath surface and top blown oxygen gas can be calculated and most of the parameters were determined based on the experimental results of the previous paper. The following phenomena were clarified by this program and the control of the hot metal dephosphorization process became possible.
(1) In the case of hot metal pretreatment by torpedo car, about 50% of top blown oxygen gas had the same effectiveness as Fe oxide for dephosphorization reaction. The remaining oxygen contributed to the heat supply through decarburization and post combustion reactions.
(2) When [P] concentration before treatment was high, the efficiency of oxygen and that of lime for dephosphorization were high but a clear dependence on temperature was not found.
(3) The efficiency of oxygen and that of lime for dephosphorization mainly depended on CaO/O and hot metal composition ([P], [Si]) although dephosphorization treatment time and flux supply rate differed widely.