Energy, exergy, emission, exergoeconomic, enviroeconomic, and sustainability analysis of diesel engine, fueled by waste cooking oil and waste polyethylene co-pyrolysis oil-diesel blends

Abstract

This study aims to evaluate the energy, exergy, emission, exergoeconomic, enviroeconomic, and sustainability aspects of a diesel engine utilizing blends of Diesel and co-pyrolysis oil. In this study, oil derived from co-pyrolysis of waste cooking oil and waste polyethylene was blended with Diesel up to 30% proportion. These blends exhibited similar physiochemical properties as regular diesel fuel. Among the blends, D90P10 (90% diesel and 10% co-pyrolysis oil by vol%) showed exceptional performance in terms of sustainability, with a sustainability index value of 1.43. Furthermore, the D90P10 blend achieved the highest energy efficiency at 33.6% and exergy efficiency at 30.3% compared to regular diesel fuel. However, it was noted that D90P10 also exhibited a maximum increase of 25.6% in NOX emissions at fuel injection timing of 25° bTDC. Overall, all the blends displayed improved efficiencies, higher sustainability index values, and lower relative costs compared to using neat diesel fuel with a penalty of higher cost of CO2. Among the tested blends, the D70P30 blend had the minimum cost of CO2, making it a promising and viable alternative to blend. In conclusion, the research suggests that the D70P30 (70% diesel and 30% co-pyrolysis oil by vol%) blend offers a compelling option to be utilized as a blended fuel with diesel, considering its favorable efficiency, sustainability, and cost factors.