Aluminum, primary/virgin

This dataset is based, at a gate-to-gate unit process level, to the corresponding global average dataset for ingot casting. It has been created to account for regional differences in the sources of electricity used to produce primary aluminium. A series of electricity markets specific to the aluminium-industry are present in the database. Regional primary aluminium production datasets, such as this one and the electrolysis datasets this one is supplied from, will link with the corresponding aluminium-industry specific electricity markets during linking. This procedure is used because (1) primary aluminium production is very electricity intensive, and hence the location of production plants is often determined by access to large amounts of cheap electricity, which often results in an electricity mix that is different from the general grid mix of the countries where the production plants are located and (2) often the grid mixes are very different from region to region.The dataset represents the production of 1kg of primary aluminium ingot. Molten aluminium produced from the electrolytic process is tapped from reduction cells, weighed, sampled and analysed before it is poured into a holding furnace and heated to approximately 750°C using natural gas as a fuel. Alloying elements, such as magnesium, silicon and manganese, for additional strength, corrosion resistance and other properties, are added to the aluminium. It is typically at this point in the process that clean, sorted scrap can also be added but for the purposes of this dataset, scrap remelting is excluded. During furnace charging and preparation, aluminium dross (a thick liquid or solid phase) forms at the surface of molten aluminium. This mixture of aluminium oxides is remelted to recover the aluminium that would otherwise be lost. Metallurgical analysis verifies that the metal meets customer specifications before the molten, alloyed (or pure, unalloyed) aluminium is cast into products of specific dimensions, before being weighed, bundled and strapped ready for transport.