Experimental analysis and optimization of CI engine performance using waste plastic oil and diesel fuel blends

From the perspective of waste plastic utilization, this paper presents an effective diesel replacement by pyrolyzed waste plastic (LDPE: transparent plastic used for packaging) oil (WPO) in CI engine and studies the parametric performance analysis with optimization of operating conditions. The WPO was produced from the 400 degrees C to 500 degrees C pyrolysis temperature and blended with diesel by volume fractions of 10%, 20%, 30%, and 40%. A total of 140 test runs were considered with input variables such as WPO-Diesel blends, Compression ratio (CR), and engine load. Experiment results showed a trade-off nature between input variables and performance. To optimize the operating conditions aiming to maximize engine power and minimize exhaust emission, Response Surface Method (RSM) was applied utilizing ANOVA analysis. The optimized operating variables were predicted to be 0.4 blending ratio (40 BR), 15.39 CR, and 12 kg engine-Load. The corresponding optimized parametric response values were found to be 3.4 kW, 0.414 kg/kWh, 34.06%, 4.153 bar, 0.02V%, 1.8V%, and 309.24 ppm for BP, BSFC, BTE, BMEP and emissions contents of CO, CO2, and NOx, respectively. The coefficient of determination for the model (R2) was found 95%, with a Composite-Desirability of 0.7332. Overall, the WPO has the potential as a fuel for CI engines under optimized operating conditions.