Table 3 Comparative performance analysis of two Al purification processes.
From: Innovative vacuum distillation technology for preparing refined Al from Al–Mg alloy
Economic & technical indicators |
VD process |
|
|---|---|---|
Al content in refined Al | 99.9989% | Less than 99.996% |
Al direct recovery efficiency | 97.98% | 95–98% |
Behavior of Al and Mg | Al-Mg alloy → Refined Al + Elemental Mg | Al-Mg alloy → Refined Al + Mg2 + salts |
Proportioning | Without additives | Electrolyte (Na3AlF6, NaCl, KCl, Na2CO3, K2CO3), graphite electrode |
Energy consumption | Electricity < 4.60 kW·h/kg | Electricity > 16 kW·h/kg |
Processing conditions | 1373 K | 993 K to 1073 K |
Waste discharge | No discharge | Dust (fluorides), gas pollutants (SO2, CO2), smelting slag |
Primary equipments | Vacuum resistance furnace | Al electrolytic cell + cathode + anode + vacuum ladle + dust collection equipments |
Technological steps | VD | Proportioning + melting + slag discharging + electrolyte replenishment + cathode replacement + Al discharging |
