Assessment of second-generation biodiesel using computational and experimental methods for the reduction of emissions and promoting environmental sustainability

The fast depletion of fossil reserves coupled with uncertainty in petroleum prices and environmental degradation has paved the way for alternative and sustainable energy resources. This study investigates the possibility of using biodiesel as a potential alternative for conventional mineral diesel. Waste cooking oil (WCO) was utilized as a feedstock for biodiesel production where pre-treatment of WCO was done via mineral acids for acid value reduction. Physio-chemical properties including calorific value, density, viscosity, cloud point, and a flashpoint of biodiesel blends were examined according to ASTM standards. Biodiesel blends B10, B20, B30, B40, and B50 were tested using a compression ignition engine. Emissions of carbon monoxide (CO), unburned hydrocarbon (UBHC), and oxides of nitrogen (NOx) were experimentally determined for biodiesel blends and were compared with high-speed diesel (HSD) as a baseline. Experimental results were used to validate various combustion and emissions parameters for diesel and biodiesel. Numerical combustion analysis of biodiesel blends and diesel were performed and compared with experimental results. The combustion temperature was taken from 300 K to 2038 K, 1431 K, 1486 K for B100, diesel, and B50 blends respectively. CFD analyses have obtained the products produced by the combustion of fuels like CO2, H2O, N2, O2, and mass fraction of C17H34O2 in both B100 and diesel. The maximum deviation between experimental and numerical results of diesel and B100 were found to be 5.06% and 5% for NOx, 6% and 5.11% for UBHC, 5.26% and 7.94% for CO.