Manganese loss during the oxygen refining of high-carbon ferromanganese melts

Decarburization tests of high-carbon ferromanganese melts by oxygen refining were successfully carried out in a model converter with 2-ton production capacity. During the oxygen refining, the manganese loss was inherently accompanied by oxidation and evaporation. The oxidation loss of manganese into slag was affected by slag composition, melt temperature and slag weight. The oxidation loss of manganese into slag was minimum at a slag basicity of about 1.5 and it increased with temperature and slag weight. The amount of manganese evaporation loss was comparable to that of oxidation loss. An empirical equation for the evaporation loss of manganese was derived as a function of process variables. The apparent vaporization coefficient, β, was significantly affected by the oxygen mixing ratio in bottom blowing gas and the fraction of top blown oxygen.