Process for recovery of free aluminum from aluminum dross or aluminum scrap using plasma energy at high enthalpy

Abstract

A process for recovering free aluminum and aluminum compounds such as aluminum oxide from aluminum dross and aluminum scrap in a furnace heated with a plasma arc torch wherein air at high enthalpy is used as the arc gas. The use of air at high enthalpy as the arc gas provides for more rapid heat output, causing the outer surface or shell of dross to heat rapidly, thereby rupturing the oxide shell releasing free aluminum from within the shell. A higher aluminum recovery is obtained. In a plasma torch high enthalpy is obtained by adding a gas such as CO.sub.2, methane or hydrogen to the air arc gas at a fixed current level or by operating the plasma torch with higher current at a fixed air flow.

Dependencies are inferred from the claim text.