Induction heating pyrolysis of landfilled plastic waste into valuable hydrocarbon fuels

This research investigated the pyrolysis process for plastic waste treatment using induction heating. The induction system involved a coil wrapped around insulated material to generate heat. The plastic waste was sourced from the Refuse-Derived Fuel (RDF) sorting process from a 15- year-old landfill in the province of Nonthaburi, Thailand. The pyrolysis was performed at temperatures ranging from 400 to 600 degrees C with a batch reactor. The highest yield of pyrolysis oil was 27.6% wt. at 600 degrees C. Energy consumption for converting plastic waste into oil ranged between 9.50 and 13.36 kWh, with the highest consumption at 600 degrees C. The produced pyrolysis oil at 600 degrees C achieved the highest HHV of 41.33 MJ/kg. The GC/MS analysis of the pyrolysis oil revealed an increase in aromatic and hydrocarbons (C5-C11 and C12-C20) with rising temperature. These carbon fractions are suitable replacements for heavy oil or diesel fuel, as low-oxygenated compounds, and hydrocarbon content in pyrolysis oil are desirable. The amount of char produced at 400 degrees C was the highest, with a yield that ranged from 45.2% wt. to 67.0% wt. Moreover, the pyrolysis process has a significant advantage in lowering greenhouse gas emissions (0.21-0.25% vol.), which releases less CO2 than the combustion of plastic waste. The findings therefore suggest that pyrolysis oil, which is produced under optimum conditions, can be used as a substitute liquid fuel in the industrial sector, and is consistent with the circular economy's concepts, promoting sustainability and utilizing resource efficiency.