Life cycle assessment of material recovery from pyrolysis process of end-of-life tires in thailand

Abstract

© 2020 by the authors. It is estimated that around 600,000 tons of end-of-life tires are generated annually in Thailand. These waste tires will cause danger to the environment and human health if handled improperly. On the other hand, if managed with the proper technology, it will be transformed into valuable products. This research aims to evaluate the potential environmental impacts of a waste tire pyrolysis plant in Thailand by using the Life Cycle Assessment (LCA) method. The functional unit is defined as 1 ton of products from the pyrolysis process of waste tires. The system boundary consists of a pre-treatment and pyrolysis process (gate-to-gate). The LCA calculations were carried out using licensed SimaPro 9.0 software. At the impact assessment step, the ReCiPe2016 method both Midpoint (problem-oriented) and Endpoint (damage-oriented) were applied, and 7 impact categories were selected (global warming, fine particulate matter formation, terrestrial acidification, freshwater eutrophication, terrestrial ecotoxicity, freshwater ecotoxicity, and fossil resource scarcity). If the avoided products from the pyrolysis process, including pyrolysis oil, steel wire, and carbon black were taken into account, the characterization results show that 3 impacts: Global warming, terrestrial ecotoxicity, and fossil resource scarcity have a negative value. While the other impacts still have a positive value resulted mainly from electricity consumption. When considering weighting end-point results, it found that human health impact was a major contribution with a totally negative value of -0.947 Pt. As a summary, the outcomes confirm that the utilization of pyrolysis avoided products and the optimization of electricity consumption in the process has the potential to drives pyrolysis to become an environmentally effective technology for end-of-tires management.