Emission and Performance in a Diesel Engine Operating on Diesel-Biodiesel-Butanol Blends Derived from Waste Cooking Oil

In this investigation, the performance and emission profiles of a diesel engine, fueled by biodiesel derived from waste cooking oil (WCO), were evaluated. The biodiesel was incorporated into diesel fuel in various concentrations, and the potential enhancement of these mixtures with butanol was also explored. Experimental trials were conducted at a consistent engine speed of 2250 rpm across five distinct engine loads (4, 5.5, 7, 8.5, and 10 kW) to scrutinize engine performance and quantify exhaust emissions. An air-cooled, single-cylinder diesel engine served as the experimental apparatus. Pure Iraqi diesel (D) was used as a baseline, prior to the assessment of several fuel blends, including D80B20 (20% biodiesel, 80% diesel), D80B10BU10 (10% biodiesel, 10% butanol, 80% diesel), and D70B15BU15 (15% biodiesel, 15% butanol, 70% diesel). The results indicated a decline in engine performance across all fuel types, with the most pronounced deterioration observed at lower loads. The brake specific fuel consumption escalated by 13.37%, 16.98%, and 3.92% for the tested blends, relative to diesel. Concurrently, exhaust gas temperatures decreased by 12.5%, 23.5%, and 2.9%, respectively. Furthermore, CO emissions diminished by 22.00%, 46.0%, and 14.4%, while CO2 emissions rose by 16.67%, 41.36%, and 11.73%, respectively, when compared to diesel. HC concentrations were curtailed by 42.55%, 69.11%, and 10.64%, respectively. NOx emissions exhibited a reduction of 3.8% and 24.9% for D80B10BU10 and D70B15BU15, while a 3.5% increase was observed with D80B20. The findings suggest that ternary mixtures were associated with less favorable outcomes compared to their binary counterparts.