Comparative analysis of waste tyre treatment technologies: Environmental and economic perspectives
Dileep Kumar, Pei Yang, Bing Han, Suiyang Khoo, Michael Norton, Scott Adams, Abbas Z. Kouzani
Abstract
Around 75 % of waste tyres are disposed of in landfills annually worldwide, posing significant environmental and resource management challenges. Several waste tyre treatment (WTT) technologies have been developed to overcome the environmental impacts of used tyres worldwide. This study aims to identify the most eco-friendly and cost-effective technology by comparing the environmental and economic performance of different WTT technologies. It first conducts a systematic literature survey to identify and select the most relevant scientific studies published in the last two decades. It discusses the technical attributes of different WTT technologies. Then, the life cycle assessment (LCA) methodology determines the selected impact categories for comparative analysis. The WTT technologies are compared against each other using selected impact categories by harmonising their characterisation factor at 1 ton of waste tyre. Afterwards, it identifies the most eco-friendly WTT technology irrespective of technical and geographical boundary conditions, comparing the minimum and maximum characterisation values of each WTT technology. The comparative analysis reveals that pyrolysis is the most efficient WTT technology, exhibiting the lowest global warming potential (−1298 kgCO 2 -eq/t), the highest resource recovery (−60 eco-points/t), and the best economic performance ($133/t profit). Pyrolysis facilitates the recovery of steel wires (150–263 kg/t), carbon black (330–380 kg/t), diesel (167 kg/t), and petrol (72 kg/t), contributing to sustainable waste management . Finally, this study proposes a carbon credit trading mechanism to ensure transparency in emissions trading and incentivise waste tyre recycling.