THERMODYNAMIC ANALYSIS OF EAFD GENERATION USING THE Fe-O-Zn SYSTEM1

摘要

The steel production in semi-integrated mills generates several types of residues -among them, the electric arc furnace dust (EAFD). In addition to Fe and oxygen, the EAFD contains the element zinc which bears economic interests, capable to motivate its extraction. Aided by a 'computational thermodynamics' tool, theoretical considerations are made for the system Fe-O-Zn (most important elements in EADF) using the variables temperature, oxygen partial pressure and composition (Fe/(Fe+Zn) mass ratio) in order to determine which phases are stable in the conditions existing inside the electric arc furnace (EAF) during the production of steel. As a result, new phase diagrams for the systems Fe-0 and Fe-O-Zn were drawn; they point to spinel as the most probable solid phase present in EAFD. Moreover, the possibility to transform franklinite into another oxide has also been addressed - this can be helpful in the hydrometallurgical processing of this waste.