INVESTIGATION ON A POSSIBLE REVIEW ON THE THERMODYNAMIC PREDICTIONS ON THE CARBON SOLUBILITY IN Mn-Fe MELT DURING CARBOTHERMIC REDUCTION USING NCHWANENG MANGANESE ORES

The high carbon ferromanganese process produces an alloy saturated with carbon. The alloy contains Mn metal, Fe and C. Carbon dissolves into the alloy, and therefore it is important to calculate the activity of manganese in the alloy. Data dealing with the solubility of carbon in liquid ferroalloy are available but only applied to specific melts. Because the dissolution of carbon into the manganese alloy was not as obvious as in steel production, the behaviour of carbon in steel production was considered the archetype and became the accepted tradition in the manganese alloy production. The assumption was considered because of the solubility of carbon in liquid. Mn, Fe and Mn-Fe present similarities in their interaction parameters. In this investigation, two different equations linear regression that are used in the steel production were tested to establish their validity when using a basic manganese ore. The deviations of the experimental carbon solubility values obtained in this study are narrow such that the fitting of the model albeit revisited but strongly reconducted and cautiously adopted, therefore not reviewed. Therefore, Turkdogan's (1956) and Tuset and Sandvik's (1970) thermodynamic predictions on the carbon solubility in Mn-Fe melt remain valid and reliable for the production of high carbon ferromanganese using basic manganese ores.