Recycling of Oxide from Dross into Alumi

Today, aluminium dross is typically recycled through melting in a gas-fired rotary furnace, with salt added for oxidation protection and to aid in the agglomeration of molten aluminium. This paper investigates an alternative method where aluminium metal and oxide are separated in a plasma heated rotary furnace without the use of salt. The innovative approach employs a plasma gas combination of argon and hydrogen to create reducing conditions, which facilitates the separation of the oxide from the dross. The oxides obtained were characterized to assess their chemical purity and physical properties, which were then compared to the required specifications for use in electrolysis. Initial findings indicate that without the salt, the resulting oxide primarily consists of elements already present in the cast houses, suggesting that the separated oxide could be reused in electrolysis cells without adversely impacting performance. Further studies are planned, including dissolution tests, to determine whether additional processing of the oxide is necessary prior to integration into the electrolysis systems.