Assessing the economic and ecological viability of generating electricity from oil derived from pyrolysis of plastic waste in China

The increased plastic waste generation worldwide poses ponderous issues for public health and the environment. China is the highest generator of plastic waste around the world. The current treatment process (incineration) of the increased plastic waste causes dangerous environmental consequences. Pyrolysis has recently surfaced as an ecologically friendly technique for energy and material recovery from plastic waste. The present study assesses the financial and ecological viability of power production from oil derived from the pyrolysis of mixed plastic wastes in China from 2009 to 2028. The prominent findings show that the amount of plastic waste collected in 2020 (24.16 Mt) increased by 53.19% in 2028.The pyrolysis of mixed plastic wastes during the project period yielded 359.29 Mt oil, which has a power potential of 1,060.86 GWh. The economic analysis indicated the project is viable and profitable with a positive net present value (US$8.80 million) and profitability index (1.26) greater than 1. The project has 10.6 y payback period, US$0.0752/kWh levelized cost of energy, 22.5% return on investment, and 13.0% internal rate of return. The life cycle assessment results show that conversion of mixed plastic waste to pyrolysis oil for electricity generation during the project period has a total global warming potential (GWP) of 1,311.4 kt CO2eq. The GWP is mainly from conversion of pyrolysis oil to electricity (73.42%), pyrolysis oil production (15.01%) and upgrading of pyrolysis oil (11.38%). The consumption of power from the project could avoid the combustion of 2,659.0 t coal, minimizing global warming by 11,278.8 kt CO2eq. Sensitivity analysis, which examines the influence of variation in sensitive factors on the success of the project, is presented. This paper provides scientific strategies for optimal investment and decision-making on the environmental sustainability of plastic waste-to-energy pyrolysis projects.

Automated summary

The increasing generation of plastic waste globally is causing major concerns for public health and the environment, with China being the largest contributor. The current method of incineration for treating the increased plastic waste has negative environmental consequences. Pyrolysis has emerged as an environmentally friendly technique for energy and material recovery from plastic waste. This study evaluates the financial and ecological feasibility of power production from oil derived from pyrolysis of mixed plastic wastes in China from 2009 to 2028. The findings show a significant increase in plastic waste collected by 2028, with the potential to generate a substantial amount of oil for power production. The project is economically viable and profitable, with positive indicators such as net present value, profitability index, and return on investment. The life cycle assessment results reveal the project's positive impact on reducing global warming through the avoidance of coal combustion.