The production of aluminium is an energy intensive process—so much so it is sometimes referred to as ‘solidified energy’. Carbon emissions are produced in aluminium smelting from the required electricity generation, along with the direct emissions from the reduction of alumina with a carbon anode.
Consumers are increasingly looking at the full value chain of materials with an ESG lens and governments are looking broadly across industries to meet global commitments. The reduction of emissions in alumina refining will be expected, with failure to act potentially penalised. While smelting produces a large proportion of carbon emissions and is often the focus of decarbonisation efforts, alumina refining is still an energy intensive process. It uses high pressure steam to produce the heat input required to process bauxite into alumina. It also uses fossil fuels in its calcination processes. Alumina is then converted to aluminium in a smelting process, which releases a large amount of carbon.