Improvement in combustion and emission characteristics of biodiesel fuel (KOME) by supplementary bio-based fuels

In spite of environmental benefits of biodiesel, it suffers from higher viscosity, cold starting problems and increased nitrogen oxides (NOx) emissions when compared with diesel fuel.In this research work, ethanol (EtOH) and diethyl ether (DEE) were used as the supplementary renewable bio-based fuel to improve combustion, emission characteristics and fuel properties of biodiesel (KOME) through an experimental investigation. Ethanol was added to the pure biodiesel (KOME) and optimized its blending ratio which found to be 15% ethanol. Thereafter various percentage of DEE namely 5, 8, 10, 15 and 20(vol %) was added to the optimum selected ethanol-biodiesel blend (B-E15) and optimized its blending ratio to overcome the poor ignition quality of ethanol when utilized in diesel engine.Some physicochemical properties of test fuels were determined in accordance to the ASTM standards.The results obtained from the engine tests have shown a significant reduction in NOx emissions especially for DEE addition of more than 10% on a volume basis. A global overview of the results has shown that the 15% DEE-KOME blend is the most effective combination based on performance and emission characteristics.

Keywords:

Diesel engine , biodiesel , ethanol , Diethyl ether