ALUMINIUM Extra
‘ The Facts About Aluminium Recycling ’
Aluminium has enjoyed an extensive recycling lifespan since its commercialisation in the 1880s with the advent of the Hall – Héroult process , in fact , 75 % of all the aluminium produced since this time is still in active use today . Aluminium has an enviable scrap value and ‘ clean ’ scrap can cost almost the same as new ‘ prime ’ aluminium . The industry demand for recycled aluminium is driven by the demand for low-carbon aluminium , as recycling aluminium uses just 5 % of the energy needed to produce ‘ prime ’ aluminium from mined bauxite .
BY PHIL SLINGER - CAB CHIEF EXECUTIVE
Low-carbon aluminium produced into billet or logs , the raw material used in the extrusion press , can be produced to less than 3.0 tCO 2
e ( Tonnes of CO 2 equivalent ) when 60 % to 70 % of recycled material is mixed with a low-carbon prime aluminium . As you would expect , there is a high demand for this billet which comes at a premium . In reality all new aluminium used globally , across all industries , on average contains by volume one third recycled aluminium . The difficulty in obtaining scrap is due to the aluminium product , be it in transport or construction , is still in active use due to extensive life expectancy . Some of the oldest installed aluminium windows , installed at the Bodleian Library in Oxford , are over 80 years old and still going strong .
Today we recycle a higher percentage of our scrap aluminium as extraction rates from deconstruction of our structures has increased to almost 100 %, such is the value of the metal . In fact , many aluminium supply chains now see our cities as ‘ urban mines ’ for the future extraction and re-use of aluminium used in both construction and transport infrastructure .
What is new today is the ability to recycle aluminium back into their original
‘ grades ’. Pure aluminium is rarely used as it is normally formed into an aluminium alloy which contains other materials that give the alloy special characteristics . The typical alloying elements are copper , magnesium , manganese , silicon , tin , nickel and zinc . There are many globally recognised grades of aluminium alloy which are placed into a long list or ‘ series ’ of different characteristics which are used in various applications . For wrought aluminium used in the architectural aluminium extrusion process , we generally use an alloy grade 6063 . The ability to recycle in a single grade is helped by using modern , handheld alloy analysers . These XRF ( X-Ray Fluorescence ) analysers perform a quick , non-destructive analysis of scrap so grades can be grouped together for recycling .
Keeping the grades segregated means that the scrap aluminium has a higher value to a reprocessor ensuring that former architectural installations can be collected and made back into windows , doors and curtain walls .
There are two recognised areas of scrap collection , pre-consumer and post-consumer . As its name suggests , pre-consumer scrap is offcuts and damaged material from manufacture , post-consumer scrap is aluminium collected from the building deconstruction process or where an existing building is being refurbished . The
40 NOVEMBER 2022 CLEARVIEW-UK . COM