End-of-Life Tyres: Comparative Life Cycle Assessment of Treatment Scenarios

Waste tyres and their accumulation is a global environmental concern; they are not biodegradable, and, globally, an estimated 1.5 billion are generated annually. Every year around 350,000 tons of end-of-life tyres (ELT) are managed in Italy, collected from cars, two-wheeled vehicles, trucks, up to large quarry vehicles and agricultural vehicles. ELTs are collected and sent for material or energy recovery, in line with the circular economy principles. This paper investigates the environmental impacts of two common scenarios of ELT treatments. Specifically, it is analysed the recycling of crumb rubber (CR, deriving from the tyre shredding) for the composition of bituminous mixtures for the wearing course of roads. This scenario is compared with the energy recovery route in a dedicated incinerator. To this aim the standardised methodology of Life Cycle Assessment (ISO 14040-44) is employed. Results shows that for most part of the impact categories analysed, the material recovery presents higher environmental benefits if compared with energy recovery.