Exhaust Emissions Characterization of a Single Cylinder Diesel Engine Fueled with Biodiesel-Ethanol-Diesel Blends

Energy is one of the most important resources to mankind for his sustainable development. The decline of available oil reserves and more stringent environmental regulations have motivated the global interest in renewable energy sources. Due to exponential growth in industrialization, the demand for conventional automotive fuels is also increased sharply which adversely affects not only the economy but also the environment. This makes the search for an alternative fuel more important today. In this research, the blends of ethanol and biodiesel with diesel in varying proportions were used to access the emission levels of the blends. The emission levels were investigated under various operating conditions of the engine. Emission levels of carbon dioxide (CO2), carbon monoxide (CO), hydrocarbon (HC), oxides of nitrogen (NOx), oxides of sulfur (SOx) emissions and exhaust gas temperature were investigated. The results showed that the BED30 fuel gave the best exhaust emission. The tests were carried out on a horizontal single-cylinder, 4-stroke, air-cooled, 3.68 kW engine, TecQuipment TD115 MK-II model. The engine was coupled to a manometer (model: Z30EBIX25) and DG eddy current dynamometer (model: WB2.7 PB43) with rated power of 3.68 kW at 2600 rpm and was operated at a constant load of 1000 g. The test results showed that, there was a considerable increase in exhaust temperature with the blends compared to the diesel. The exhaust gas temperature of BED30 appeared to be similar to that of the diesel at all speed conditions. The results also showed that the blends gave less CO compared to diesel. The minimum and maximum reduction of CO was 9.5 and 49.1% respectively of the blends, as compared to diesel. The emissions of NOx, SOx and CO2 increased with increase in ethanol in the blends. All the findings compared favorably with the results of other researchers.