TEMPERATURE-DEPENDENCE OF PHOSPHORUS DISTRIBUTION RATIO BETWEEN CAO-SIO2-CAF2 SLAGS AND FE-CR-C ALLOYS

In viewing the removal of phosphorus from chromium-containing hot metals produced by smelting reduction processes, the temperature dependence of phosphorus distribution ratio between Fe-11.5mass% Cr-C-satd alloy and the CaO-SiO2-CaF2 slag saturated with CaO, 3CaO . SiO2 and CaO . Cr2O3 has been investigated from 1517 to 1673 K. In contrary to general trend of dephosphorization, phosphorus distribution ratio was found to increase with increasing temperature, showing good agreement with thermodynamical evaluation with the assumption that the oxygen partial pressure is controlled by chromium is the metal phase and CaO . Cr2O3 formed in the slag, This study indicated that high-temperature treatment would be favorable for effective dephosphorization of chromium-containing hot metals.