Synergistic effect of biogas and waste Annona seed biodiesel on dual fuel engine performance and emissions

This study investigates the use of raw biogas as an alternative fuel in combination with waste Annona seed-driven biodiesel and a diesel blend in a dual-fuel mode diesel engine. The Annona seed oil is first transesterified into biodiesel and then blended with conventional diesel fuel at a 20% (B20) ratio. The biogas flow rate is adjusted to 1, 2, and 4 L/min while the engine runs on the B20 test fuel. A Venturi gas mixer is utilized to ensure a uniform mixture within the combustion chamber. The engine operates at a constant speed of 1500 rpm across various load conditions (25%, 50%, 75%, and 100%). The findings depict that biogas introduced at a flow rate of 1 L/min shows the best performance, yielding the lowest emissions among the tested flow rates. In dual-fuel operation with a BD10 BG at a 1 L/min biogas flow rate, the brake thermal efficiency (BTE) drops by 9.94% and the brake specific fuel consumption (BSFC) increases by 8.82% compared to diesel. CO and HC emissions rise by 5.18% and 3.01%, respectively, but NOx emissions decrease by an average of 14.91%. This study of dual-fuel CI engines running on biogas and biodiesel demonstrates a viable pathway to cleaner, more efficient dual-fuel CI engine operation, advancing sustainable energy solutions in alignment with SDGs 7, 12, and 13.