Performance Evaluation and Emissions Characteristics of a Compression Ignition Engine Using Castor oil based Biodiesel

Abstract

As world is confronted with twin crisis of fossil fuel depletion and environmental degradation, greater use of fossil fuels, high import cost of diesel & petrol, growing pollution has make biodiesel an attractive alternative fuel to meet the future energy demand. Biodiesel is an alternative, clean, environmental friendly and biodegradable fuel. As nation is facing a shortage of edible oil, it would not be feasible to produce biodiesel by edible oils. Castor oil is non-edible oil thus it opened a good opportunity to study its suitability to produce castor biodiesel. The major issue with castor oil was its viscosity which creates poor fuel atomization, carbon deposits formation problems in the conventional diesel engine. A well known base transesterification method was used for castor biodiesel production using methanol and NaOH. The fuel properties of castor biodiesel blend B100 were studied and compared with petrodiesel. Blending of biodiesel with diesel in different proportions such as B20, B40, B50 were tested in diesel engine. In this present work, an experimental investigation has been carried out in a single cylinder diesel engine at a constant speed of 1500 rpm from no load to 60% of full power to evaluate the performance and emission characteristics of castor biodiesel blends such as B20, B40 and B50. The fuel properties such as calorific value, kinematic viscosity, flash and fire point, cloud and pour point of castor biodiesel have been determined as per ASTM standards. The performance parameters include brake power, brake specific fuel consumption, brake thermal efficiency. The measurement of exhaust emissions includes hydrocarbon, carbon dioxide and carbon monoxide has been carried out at different loads with different blends of biodiesel. Test results indicate that at full load, the brake power produced by castor biodiesel blend B20 is 3.125% less than that of diesel and brake specific fuel consumption of castor biodiesel blend B20 and diesel is almost same. At all loads, brake thermal efficiency of castor biodiesel blend B20 is higher than that of diesel and other blends B40, B50. The castor biodiesel blends emits carbon dioxide, hydrocarbon and carbon monoxide slightly lower than that of diesel at all loads. It is concluded that castor biodiesel blend B20 is a best candidate of alternative fuel among all tested fuel at full load conditions.