Practical application of circularity micro-indicators to automotive plastic parts in an industrial context

The increasing amount of plastics in new vehicles, and the consequent growth of plastics in the automotive shredder residue, makes it imperative and urgent to improve reuse and/or recovery of plastics at the vehicle’s end-of-life. Circularity micro-indicators can identify improvement guidelines and monitor the transition to a more circular economic model; however, the complexity, variety of scope and approach, and scarcity of information on most of the circularity micro-indicators hamper their practical adoption by companies. In this paper, we identify relevant micro-indicators for the automotive sector, focusing on key aspects for automotive plastic parts. Further, to showcase the application of these micro-indicators in a real industrial context, a case-study plastic automotive component was identified in collaboration with a tier II supplier and five complementary circularity micro-indicators were evaluated. We found 23 circularity micro-indicators (at the product level) that are highly relevant for automotive parts and we discuss individually how each can provide useful information. Results indicate an enormous improvement opportunity to improve circularity of plastic automotive parts, namely in the use of more sustainable material sources (recycled, bio-based, or compostable materials) and promotion of end-of-life recovery approaches (reuse or refurbish, and take-back systems). We concluded that practices adopted by industry to optimize production, in terms of design for manufacturing and design for assembly, as well as in the composition of plastic automotive parts, namely integral design, multi- material parts, or welding components made from different materials, severely limit the implementation of circular economy approaches, a situation that needs to be reverted by legislators and companies.FCT -Fundação para a Ciência e a Tecnologia(UI/BD/150827/2021