The high intrinsic value of aluminium building scrap has always been the main impetus for recycling, independent of any legislative or political initiatives. A Delft University study showed that the end-of-life collection rates for aluminium in the building sector were found to vary between 92% and 98%, demonstrating aluminium’s pivotal role in the pursuit of sustainability in construction. The old Wembley stadium was one of the projects monitored by the Delft team and it attained a 96% recovery rate. Typically the 4% loss was due to handles, hinges and similar small items being lost in the deconstruction process. As more sophisticated recovery procedures are introduced even these items are now being captured. “96% aluminium recovery from the old Wembley” Aluminium scrap has high value due to the high embodied energy stored within it, resulting in a 95% saving on energy costs over those incurred in primary metal production.
Furthermore, since its atomic structure is unaltered during the refining process, aluminium can be recycled again and again without loss of physical properties or value. Aluminium enjoys a ‘cyclic’ economy as most aluminium products are not consumed, merely used. Hence it is renowned for its ‘cradle-to-cradle’ life cycle where, for instance, the material from an aluminium can could end up in a curtain walling extrusion or vice versa. Neither does the age of the material have any adverse effect on its recyclability and, equally important, new and recycled aluminium have virtually the same value. As aluminium is such a recyclable material we are beginning to build up a ‘bank’ of aluminium in use and the aluminium industry has set up an initiative to help communicate this in the industrial sector.
The Aluminium for Future Generations programme monitors this bank of aluminium, looking at the inputs, the bank in use, and any losses. By analysing this data we can maximise our use of the material in all walks of life. Of products in use, building takes the largest share at 31% of the total. Primary aluminium entering the ‘bank’ will be recycled many times over in the coming centuries at only 5% of the initial energy used to produce the aluminium from bauxite.
The Life Cycle Circle – European Aluminium Association ©