Thermochemical recycling of polystyrene waste by pyrolysis using a pilot-scale auger reactor: Process demonstration in a relevant environment

Abstract

This study presents the pyrolysis of polystyrene waste using a single-auger pyrolysis reactor at an industrially relevant scale, i.e. within the fifth technology readiness level (TRL-5). In order to gain a better understanding of the influence of the main variables involved in this technology, a thorough experimental campaign was performed with PS feed rates of 6 and 9 kg/h, covering a temperature range of 450–600 °C. These variables influence not only the distribution of the products, but also the presence of compounds that may affect the suitability of the pyro-oil for re-polymerisation processes. In this sense, gas chromatography (GC), gas chromatography coupled to mass spectrometry (GC/MS) and simulated distillation (SimDist) of the resulting pyro-oils provided valuable insights into styrene purification. The data collected confirms the strength of the auger reactor for thermochemical recycling of polystyrene waste, and contributes to the future development of the plastics circularity on an industrial scale.