Enhancing the Metal Yield of the Rotary Converter Melting of Aluminium Drosses with Simple Sodium-Chloride: Thermodynamic and Kinetic Consideration

The rotary converter melting of Al-containing drosses with and without NaCl addition was examined. It was found that simple NaCl can enhance the recovery by 9% while decreasing the mass of the secondary dross. It implied a significant decrease in the metallic Al concentration, which indicates a superior coalescence of the molten metal drops when NaCl is present. However, the thermodynamic analysis showed that it might also imply the possibility of a certain degree of aluminothermic and magnesiothermic reduction of NaCl. On the other hand, neither the analysis of the flue dust nor that of the tapped metal showed the presence of the reaction products; thus, no melt contamination occurred.