Recycling waste plastics in roads: A life-cycle assessment study using primary data

The present study investigates – from an environmental perspective – the processes that lead to the conversion of
waste plastics into recycled plastic pellets to be used either as an additive (wet method) or as a replacement of
natural aggregate (dry method) in the production of asphalt mixes. Data from recycling facilities in Victoria,
Australia, were collected and used as the basis for a comparative life cycle assessment (LCA) study. Analyses
were conducted by considering several replacement ratios of virgin material by its recycled counterpart in the
so-called wet and dry method. A case study considering the production of recycled-plastic asphalt to be applied
in the construction of a typical surface layer of a road in Victoria was evaluated. In general, the results show that
recycling plastics as a polymer for bitumen modification and as a synthetic aggregate replacement in asphalt
mixes has the potential to be environmentally advantageous compared to their virgin counterpart (i.e. virgin
polymers and natural quarry aggregates).