EAF Carbothermic Co-Reduction of Alumina and Silica for the Direct Production of Al-Si Master Alloy

摘要

A key alternative for primary aluminum production could be thecarbothermic reduction of alumina. Developed concepts faceproblems with the high solubility of carbon in liquid aluminum,the presence of the oxycarbide slag and the high volatilization ofaluminum at elevated processing temperatures. In order toovercome some of these obstacles, in the framework of theENEXAL FP7 project, research into the co-reduction of aluminaand silica was made, aiming at the direct production of Al-Simaster alloys. The latter are key commercial products for allcasting applications, accounting for approximately 30% of allaluminum demand. As predicted by the thermodynamic study andverified by lab scale EAF experiments, the presence of silicon inthe system suppresses volatilization phenomena, limits theoxycarbide slag formation and reduces carbon solubility in themetal phase.