(2024) Energy Conversion and Management_Production of aviation fuel via thermal cracking of plastic waste

Lee T.; Jung S.; Lee S.; Tsang Y.F.; Lee K.H.; Kwon E.E.

(Elsevier Ltd) Energy Conversion and Management ISSN: 1968904 Vol.315 Issue. Article No.118827 DOI: 10.1016/j.enconman.2024.118827

Despite the calorific value of plastic waste being comparable to that of fossil fuels, its direct utilisation in the internal combustion engine is not a viable option due to a technical difficulty in optimising the equivalence ratio. To address this issue, this study proposes a pyrolysis system for the conversion of plastic waste, especially high density polyethylene (HDPE), into liquid fuels compatible with aircraft turbojet engines. Given a broad spectrum of pyrogenic hydrocarbons (HCs) derived from HDPE, it is important to shorten the chain length to produce aviation fuel-like products with carbon numbers ranging from 8 to 16. To this end, this study modified the typical pyrolysis setup by additionally adopting a heating element, isothermally operated at 500–800 °C. Also, the condensation system for collecting the pyrogenic HCs was designed using two consecutive units (set as 20 and −40 °C) for the selective recovery of jet-fuel-range HCs. The reaction temperature of 600 °C exhibited the similar composition of HDPE-derived fuel with commercial aviation fuels (Jet-A, JP-8, and JP-5). Subsequently, thermodynamic calculations of HCs collected in the second trap were performed in an ideal turbojet engine cycle. It was confirmed that the fuel performances of HDPE-derived fuel (produced at 600 °C) were comparable to commercial ones. Therefore, this study proposed that modification of pyrolysis and condensation system facilitated the production of jet-fuel-range HCs derived from HDPE. © 2024

This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean Government (MSIT) (Grant No. NRF-2023R1A2C3003011).