Investigations on Dual Fuel Reactivity Controlled Compression Ignition Engine using Alternative Fuels Produced from Waste Resources 2022-01-1095

Currently, alternative fuels produced from waste resources are gaining much attention to replace depleting fossil fuels. The disposal of waste plastic poses severe environmental problems across the globe. The energy embodied in waste plastics can be converted into liquid fuel by pyrolysis. The present work explores the possibility of utilizing waste plastic oil (WPO) produced from municipal plastic wastes and waste cooking oil (WCO) biodiesel produced from used cooking oil in a dual fuel reactivity-controlled compression ignition (RCCI) mode. A single-cylinder light-duty diesel engine used for agricultural water pumping applications is modified to run in RCCI through suitable intake and fuel injection systems modifications. Alternative fuel blends, viz. WPO and WCO biodiesel with 20 vol. % in gasoline and diesel is used as a port and direct-injected fuels in RCCI. The premixed ratio and direct-injected fuel timings are optimized to achieve maximum thermal efficiency. The engine combustion, performance, and exhaust emissions with waste fuel blends are compared with gasoline and diesel (G/D) as a port and direct-injected reference fuels. The results show that compared to G/D RCCI, the unburned hydrocarbon (HC) and carbon monoxide (CO) emissions are reduced by up to 50% and 56%, respectively, with waste fuel blends. Further, the brake thermal efficiency increases by ~20%, and the brake specific fuel consumption is reduced by ~13% with waste fuel blends. The oxides of nitrogen (NO_x) emissions are increased with waste fuel blends. However, there were no significant changes in soot emission values. In conclusion, the present work shows that waste fuel blends can be used in RCCI mode with improved engine performance and reduced emissions, except NO_x. Thus, the present study provides a sustainable global waste management solution through effective utilization in high efficiency, clean combustion diesel engine operation.