Influence of Coconut Biodiesel and Waste Cooking Oil Blended Fuels on Engine Performance and Emission Characteristics

Abstract

Due to diminishing petroleum reserves and the environmental consequences of exhaust gases from petroleum fuelled engines, alternative fuels are becoming increasingly important for diesel engines. The processed form of vegetable oil (Biodiesel) and waste products (waste cooking oil) offer attractive alternative fuels for compression ignition engines. In this study experimental work has been carried out to investigate engine performance parameters and emissions characteristics for direct injection diesel engine using coconut biodiesel and waste cooking oil blends without any engine modifications. A total of three fuel samples, such as DF (100% low-sulfur diesel fuel), CB10 (10% coconut biodiesel and 90% DF), and C5W5 (5% CB + 5% waste cooking oil and 90% DF) respectively are used. Engine performance test was performed at 100% load keeping throttle 100% wide open with variable speeds of 1500 to 2400 rpm at an interval of 100 rpm. Whereas, emission tests were carried out at 2300 rpm at 100% and 80% throttle position. As the results of investigations, there has been a decrease in torque and brake power, where increase in specific fuel consumption has been observed for blend fuels over the entire speed range as compared to diesel fuel. In case of engine exhaust gas emissions, lower HC, CO, CO2 emissions and higher NOx emissions, were found for fuel blends compared to diesel fuel. However, sound level for both blend fuels was lower as compared to diesel fuel. It can be concluded that CB10 and C5W5 can be used in diesel engines without any engine modifications and have beneficial effects both in terms of emission reductions and alternative petroleum diesel fuel. However, C5W5 produced better results compared to CB10.