Current End-of-Life Vehicle (ELV) recycling processes are mainly based on
mechanical separation techniques. These methods are designed to recycle those
metals with the highest contribution in the vehicle weight such as steel,
aluminum, and copper. However, a conventional vehicle uses around 50 different
types of metals, some of them considered critical by the European Commission.
The lack of specific recycling processes makes that these metals become
downcycled in steel or aluminum or, in the worst case, end in landfills. With
the aim to define several ecodesign recommendations from a raw material point of
view, it is proposed to apply a thermodynamic methodology based on exergy
analysis. This methodology uses an indicator called thermodynamic rarity to
assess metal sustainability. It takes into account the quality of mineral
commodities used in a vehicle as a function of their relative abundance in
Nature and the energy intensity required to extract and process them. This
method is proposed as a tool to identify the most critical components in a
vehicle so as to define specific ecodesign recommendations for them.
The methodology is applied to a SEAT Leon 2.0 Diesel III model (segment C). Main
recommendations are focused on reducing the use of metals with high
thermodynamic rarity values such as Ag, Au, Cu, Ga, In, Pd, Pt, Sn, Ta, and Te.
These metals are mainly used in electrical and electronic equipment. It is also
recommended to reduce the disassembly time of a number of critical components
such as airbag unit, electronic control unit, lighting switcher, antenna
amplifiers, panel instrument, sensors, infotainment unit, light-emitting diodes
(LEDs), and motors. A fast and easy disassembly would allow in subsequent phases
to apply specific recycling processes based on mechanical and hydrometallurgical
hybrid approaches instead of only mechanical separation techniques.