Experimental investigation of the suitability of 1-butanol blended with biodiesel as an alternative biofuel in diesel engines

Vegetable oils, biodiesels, bio-alcohols and bio-gas are some of the popular biofuels evaluated for their suitability in compression-ignition (CI) engines. Among these, bio-alcohols can be produced from any kinds of biomass through fermentation and biosynthesis and they do not require extra land for cultivation. Therefore, bio-alcohols can be considered as the next generation alternative fuels for automobiles. Investigations have been already initiated to determine the effects of bioalcohols, such as methanol and ethanol, in automobiles as fuel. However, they pose some problems like miscibility, phase separation, low cetane number and low calorific value. On the other side, the effects of higher alcohols, such as butanol, pentanol, octanol, are investigated very rarely. In this work, the effects of higher alcohol addition on the engine performance and emissions characteristics are investigated on a single cylinder diesel engine. Conventional diesel and biodiesel are taken as the reference fuels. 1-Butanol of blends (10%, 20%, 30%, 40%, and 50%) was mixed with the remaining biodiesel as the testing fuel blends. Experiments were conducted on a single cylinder compression ignition diesel engine for four load conditions (5 kg, 10 kg, 15 kg and 20 kg) at a constant speed of 1500 rpm. Brake thermal efficiency and emissions of CO, NOx and HC were recorded and discussed. From the experimental results, it is evident that the addition of butanol with biodiesel seems to an alternative fuel that can replace conventional diesel fuel in terms of both engine emissions and performance.