Combustion, Performance and Emission Characteristics of Waste Olive Oil Biodiesel in a Direct Injection Diesel Engine

In this study, a single cylinder, direct injection diesel engine was run with biodiesel from waste olive oil and the effects of diesel-biodiesel fuel blends on combustion, engine performance and exhaust emissions were investigated experimentally. The experiments were performed at maximum engine torque speed 2200 rpm, and constant intake air temperature 3.75, 7.5, 11.25, 15 and 18.75 Nm brake torques. In-cylinder pressure and heat release rate increased with the increase of engine load. Maximum in-cylinder pressure increased with the usage of fuel blends at medium and high engine loads. Thermal efficiency decreased with biodiesel fuel blends at all engine loads due to lower heating value of biodiesel than diesel. Maximum thermal efficiency decreased by about 7.1 % ve 11.7% with B10 and B20 according to diesel at full load respectively. CO and soot emissions reduced with the increase of biodiesel fraction in fuel blends. However NOx increased. NOx increased 1.5 % and 7.5% with B10 and B20 compared to diesel at full load respectively. As a result, it was seen that diesel engine can be operated efficiently with diesel-waste cooking oil biodiesel fuel blends without any modification