Two chamber stack melters and dry hearth furnaces are commonly used in the aluminium industry for melting and holding aluminium. The two chamber stack melter is a furnace consisting of two chambers stacked on top of each other, with the upper chamber used for melting and the lower chamber used for holding molten aluminium. The furnace operates on a batch process, with aluminium scrap loaded into the upper chamber and heated by natural gas burners until it melts and flows into the lower chamber.

Dry hearth furnaces, on the other hand, are designed for continuous melting of aluminium. The furnace is lined with refractory material and is heated by a combustion system, typically fueled by natural gas, propane, or electricity etc. The aluminium is melted in a shallow bath on the furnace hearth and continuously tapped from the furnace as needed.