Effects of n-Butanol Blending with Jatropha Methyl Esters on Compression Ignition Engine

摘要

The diminishing oil reserves, environmental degradation and increasing prices of petroleum-derived fuels have necessitated the search for cleaner and renewable alternative fuels, such as biodiesel. In this context, the objective of this research is to evaluate the suitability of n-butanol as a blending stock in jatropha methyl ester (JME) for use in a C.I. engine as substitute of diesel and to evaluate the performance and emission characteristics of an unmodified diesel engine. Three blends of n-butanol-JME (5, 10 and 20% n-butanol with JME on volumetric basis) were prepared. Fuel properties including calorific value, kinematic viscosity and density of blends were found to decrease with increasing percentage of n-butanol in JME. The brake thermal efficiency of the engine was higher for blends and was found to increase by increasing the percentage of nbutanol in the blends. Carbon monoxide (CO), the oxides of nitrogen (NO_X ) and smoke opacity of blends were found lower than JME during the whole experimental range. However, unburnt hydrocarbon (HC) emission was found to have slightly increased. The experimental results suggested that the engine performance had improved and emissions have significantly reduced (except HC) with blends of nbutanol and JME in comparison with neat JME. Therefore, it could be concluded that n-butanol is a potential alternative fuel to be blended with JME for diesel engine application.