Recycling vehicles and their components is a serious concern to manufacturers. (More information on the European End-of-Life Vehicle Directive.) The core materials used in most vehicles today are quite straight-forward to recycle. This page takes a look at recycling considerations within the automotive industry.
Steel is the most common material in vehicle production. It is relatively easy to reclaim and recycle. Two-thirds of steel used in US car manufacturing is recycled (source: Steel Recycling Institute); the remainder is new. Aside from environmental considerations, it is economically preferable to recycle due the large costs in obtaining steel from ore. New steel is generally used when recycled supply cannot meet demand.
Aluminium is still a small material by volume in car production. Obtaining Aluminium from Bauxite (ore) is an expensive process that requires considerable electric current; it is for this reason that Aluminium was once a semi-precious metal and has only (relatively) recently entered mainstream use. Recycling is quite straightforward with aluminium and, like steel, is economically preferable.
Plastics come in two types – Thermosets and Thermoplastics.
Thermosets are made up of strong bonds that are created with heat and subsequently do not melt with heat. This means that they cannot be reused and are either scrapped when finished with or ground down to make a filler material for something else. Thermosets are being phased out from car production as and when possible.
Thermoplastics, on the other hand, become fluid (plastic) with heat. This means they can be melted down and remoulded or added to new material. This characteristic makes them ideal for recycling on cars; it is necessary however, to match the properties of Thermoplastics carefully to their role on a vehicle; polypropylene and nylon are often used for the demanding conditions of the engine bay.
Electronic components and circuitry are often made up of thousands of complex elements which are almost impossible to seprate and recycle. Within this componentry there is a variety of toxic metals such as lead and cadmium in circuit boards, mercury in switches and flat screens and brominated flame retardants on printed circuit boards, cables and plastic casing.
When dumped, these metals contribute to a range of types of pollution with serious consequences to human health and the environment. As increasing amounts of electronics feature in cars, this will become of greater concern.