Behaviour of High-density Aluminium Briquette During Melting in Laboratory Conditions

The aluminium industry is one of the most energy-intensive industrial fields and is associated with severe environmental impact mainly due to GHG emissions. Aluminium recycling is one of the best ways to eliminate this impact and to achieve better economic viability of aluminium production. Piece size and contamination of aluminium scrap are two of the most important factors that affect recyclability of aluminium and its alloys. Scrap with large piece size is relatively easy to recycle because it is associated with lower metal loss and fewer undesired inclusions introduced into the molten metal during remelting. Unfortunately, a large portion of scrap generated by industrial sector and by end-users is of small piece size. Despite its high importance, recycling of these types of scrap is often overlooked by contemporary literature. The aim of this work is to describe melting behaviour of high-density aluminium briquette prepared from thin aluminium foils and to provide metallographic observation of inclusions introduced into the molten metal during melting of the briquette. Melting is performed in laboratory conditions. The inclusions are analysed using optical microscopy in combination with SEM and EDX analysis. The results indicates that despite fast immersion of aluminium briquette, high portion of oxide films were introduced into the melt. Carbide like particles were also observed in microstructure, probably as a result of burning of organic contamination of the briquette. However, melting process in real industrial conditions differs from laboratory experiment which is a topic for further study.