1983 Volume 69 Issue 15 Pages 1825-1831
Dephosphorization and desulfurization of hot metal with lime based fluxes were studied. The experiment was carried out by the flux injection-oxygen top blowing method. By this method the dephosphorization rate was excellently improved and the high phosphorus distribution ratio, (%P2O5)/[%1p]=5001500, was constantly attained when CaO/SiO2 in slag was more than 3.0. And by mixing fluxes with soda ash, the dephosphorization rate was kept at higher level and the desulfurization rate was remarkably improved.
In this method, many reactions concurrently proceed at various sites. A large portion of dephosphorization occurred at the oxygen fire spot. The desulfurization reaction mainly proceeded during the flotation of injected flux. At the oxygen fire spot, however, resulfurization and gaseous desulfurization reactions also occurred. The contribution of top slag which is called "permanent reactor reaction" was little. Effects of (%Na2O) on the phosphorus distribution and the sulfur distribution were 1.75 and 5.62 times as much as those of (%CaO), respectively.