Definitions of pre- and post-consumer scrap aluminium
Aluminium can be used again and again, without loss in quality. It is one of few materials that keeps its properties after recycling. But aluminium is not just aluminium. The same goes for recycled content.
WICONA uses process scrap aluminium and post-consumer scrap material as sources in secondary metal production. Both are considered recycled content by the aluminium industry. Yet they are quite different.
Process scrap, or pre-consumer scrap, is production waste from manufacturing processes, such as extrusion. Such scrap also comes from handling damages that occur during transport, as well as clippings, stampings and various trims in the production of the final product. It is metal that has not been applied in a consumer product – it has never been used. It is collected from the shop floor, and later melted and used in the production of new billets.
Post-consumer scrap is metal that has been used in a product that has gone through its full lifecycle. The post-consumer stage starts when a used aluminium product is ready for disposal, recycling or reuse. An aluminium window frame in a building is considered post-consumer scrap when the building is demolished and the aluminium is obtained and re-melted, then applied in a new product. Recycling post-consumer scrap reduces the carbon footprint of the new product. Process scrap does not. This is because post-consumer scrap has already been used for a product lifetime.
Of course, the metal is recycled in both cases, and this is positive, considering that when we recycle aluminium, we save about 95% of the energy used in the production of primary aluminium.
Definitions according to ISO 14021
WICONA also endorses the definitions for recycled content according to ISO 14021, which specifies the requirements for self-declared environmental claims regarding products. These definitions are more technical than the industry definitions, but with no meaningful differences.
Advanced technology needed
Another significant difference between the two types of scrap is that it is more difficult to produce high-quality metal that has a high content of post-consumer scrap, than with pre-consumer scrap. The latter is basically virgin metal, while post-consumer scrap is not.
Example: An aluminium window frame is normally anodized and painted. It may contain thermal break. Recycling the aluminium from a window frame is a complex process with many steps, which include inspection, separation, shredding and de-coating. After shredding in small chips, the metal is x-rayed to determine its mass characteristics, then segregated. WICONA’s parent company, Norsk Hydro, has the advanced technology that is needed to carry out these steps, which is important, because this is real recycling. The higher the recycled post-consumer content in aluminium, the lower the carbon footprint. Hydro CIRCAL, which contains a minimum of 75% post-consumer aluminium, delivers the lowest carbon footprint in WICONA’s product offering.