Process design and techno-economic analysis of the coproduction of oil, electricity, and protein from plastics and biomass using an integrated system

To synergistically exploit plastic and biomass, a hybrid system combining pyrolysis and gasification has been proposed, which has been dedicated towards the conversion of non-recycled plastic and biomass to the coproduction of oil, electricity, and protein. Non-recycled plastic is transformed into high-value pyrolysis oil, char, and gas through pyrolysis. Simultaneously, biomass undergoes gasification to produce high-quality syngas. Part of this syngas is utilized in a gas-steam combined cycle to produce electricity, while another portion is mixed with pyrolysis gas to produce protein. This innovative hybrid system reduces greenhouse gas emissions and environmental pollution compared to traditional methods. Additionally, the diversification of energy outputs enhances the system’s overall efficiency and its ability to meet varying energy demands. The proposed system achieves a total energy efficiency of 55.33 % and an exergy efficiency of 52.83 %. Furthermore, it boasts a short dynamic payback period of 3.36 years and a high net present value of 144,603.61 k$.