Reduction of Emissions in Diesel Engine Using Blended Diesel with Edible Bran Oil

Compared to other internal combustion engines, the diesel engine contributes a considerable part in air pollution; especially by emission of sulfur oxides (SOx) along with oxides of nitrogen (NOx), carbon monoxide (CO), and hydrocarbon (HC); those have a significant effect on the environment as well as on the human health. In concern to the fact, regulating the emissions of diesel engines to the environment has become mandatory. Blending of biofuel with diesel is found to be one of the sustainable methods of emission reduction from diesel engines. Thus, in this work, rice bran oil (RBO) is blended with pure diesel in different concentrations (0%, 15%, and 30% v/v) to measure the emission and performance of a Kirloskar-made stationary single-cylinder diesel engine having variable compression ratio (VCR) facility. During the experiments, the compression ratio (CR) is varied between 14 and 18, while the engine loading is done in a step manner (no load, half load, and full load). Maximum BTE is noted to be about 25% when the engine runs via 30% RBO blended diesel (B 30) at CR = 18, and the corresponding value of brake power (BP) is 3.5 kW. It is observed that the emission from the engine is decaying with an increase in RBO blending almost at all the compression ratios. Interestingly it is also noted that the change in brake thermal efficiency (BTE) is almost marginal when the engine runs via blended fuel as well as runs via pure diesel. This work recommends blending of the RBO up to a limit of 30% in diesel, and the engine is to be operated near half-load condition.