The thermodynamics for reduction of iron-chromium ore by carbon is discussed. The thermodynamic properties of iron-chromium ore were evaluated from our previous work on the activities of constituents in the FeO · Cr2O3-MgO · Cr2O3-MgO · Al2O3 iron-chromite spinel-structure solid solution saturated with (Cr, Al)2O3, and those of the Fe-Cr-C alloy were estimated by a sublattice model. The stability diagrams were drawn for carbon reduction of pure FeO · Cr2O3, (Fe0.5Mg0.5)O · (Cr0.8Al0.2)2O3 iron-chromite solid solution, and South African iron-chromium ore. The evaluated stability diagrams agreed well with the literature data. It was concluded that the lowest temperature for reduction of FeO · Cr2O3 in the iron-chromium ore was 1390 K and a temperature higher than 1470 K would be necessary to reduce Cr2O3 in MgO · (Cr,Al)2O3 in the prereduction process of iron-chromium ore. The composition of liquid Fe-Cr-C alloy in equilibrium with iron-chromium ore was also estimated under 1 atm of CO at steelmaking temperature. The predicted metal composition showed reasonable agreement with the literature values.
|Number of pages||10|
|Journal||Metallurgical and Materials Transactions B: Process Metallurgy and Materials Processing Science|
|Publication status||Published - 1998|