Aluminium
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Background
Aluminium has been recycled since it was first produced and today recycled aluminium accounts for 33% of global aluminium use world-wide. Recycling is an essential part of the aluminium industry and makes sense economically, technically and ecologically. At the end of their useful life, all aluminium products retain some worth which guarantees that it is possible to create value by recycling them into new products. Efficiency of aluminium recycling thus translates into high recycling rates for the various applications.
Aluminium that is used for recycling can be described with two categories: new and old scrap.
New Scrap
New scrap is the surplus material that is discarded during the manufacturing of aluminium alloys (e.g. the trimmings).
Most new scrap reaching the secondary industry comes directly from the manufacturing industry. It is usually of known quality and composition and often uncoated. It can therefore be melted down with little preparation. 100 % of the arising fabrication scrap is remelted by the aluminium industry.
Old Scrap
Old scrap is aluminium material that is recovered when an aluminium article has been produced, used and finally discarded at the end of its useful life. Such scrap could be e.g. used beverage cans, car cylinder heads, window frames from a demolished building or old electrical conductors.
Old scrap comes to the recyclers via a very efficient network of metal merchants who have the technology to recover aluminium from motor vehicles, household appliances, etc. This is often done using heavy equipment such as shredders, normally together with magnetic separators to remove iron, and sink-and-float installations to separate the aluminium from other materials.
Processing of Scrap
Both types of scrap are processed prior to melting to get rid off any contamination that may be present. They are centrifuged and dried to remove the oil and water that may be present and then magnetically separated from any present iron. Used beverage cans are processed to remove the interior lacquer coating and the outside product display printing inks.
The Products
The recycling of old scrap is normally carried out by secondary aluminium refiners, whereas new scrap is predominantly recycled through aluminium remelters.
Secondary