Life Cycle Analysis of CI Engine Using Bio-diesel and Di ethyl Ether (DEE)

Abstract

The gradual reduction of world petroleum reserves, growths in prices of petroleum based fuels and environmental pollution. The exhaust created by engine emissions have heartened studies to search for unconventional fuels. Bio-diesel - derived from vegetable oil - is an unconventional diesel fuel containing alkyl mono-esters of fatty acids. It has remained the focus of extensive amount of recent research since it is renewable and reduces the emission of some pollutants. The appeal of evolving bio-diesel from different tree borne oil seeds and declining the need on petroleum based fuels has been discussed by several over the past few years. Though some of the significant issues like compatibility of bio-diesel with the crankcase lubricating oil, thermal stability of lubricating oil with bio-diesel, changes in physical and chemical properties of lubricating oil with bio-diesel etc. have not been adequately inspected. This requirements to be addressed in order to confirm the long term suitability of bio-diesel in a current family of diesel engines. In the present work these problems have been addressed. With an overall objective of life cycle analysis, a long run endurance test was carried out on CI engine. Two fresh single cylinder four stroke, water-cooled, multi fuel CI engines were run for 512 hours with diesel and optimized blend of bio-diesel fuel (B20A4) respectively. The endurance tests were directed as per ISO 10000 part IX. The performance, emission, oil analysis including atomic absorption spectroscopy (AAS), ferrography were carried out for four intervals of 128 hours for detecting the amount of metal debris in the lubricating oil. Along with this weight and dimension measurements as well as surface roughness analysis were done on engine components to detect amount of wear. The experimental measurements were carried out for the brake thermal efficiency, mass of fuel consumption, brake specific energy consumption, brake specific fuel consumption as per ISO 10000 part IV. Moreover, the exhaust gases ( NOx, CO, CO2, HC and O2 ) are also measured, at 128 hours of interval, for both the engine fuelled with diesel and B20A4. The emissions of exhaust gases were measured and compared with standard limit of Bharti (Trem) stage III norms. At the end of endurance test, the wear measurement test for vital parts of the engine were also carried out. The wear measurement tests were directed as per ISO 10000 part V. The experimental results during long term endurance test shows that, the performance (mass of fuel consumption, brake specific fuel consumption, brake specific energy consumption and thermal efficiency) of engine, fuelled with B20A4 was found to be (6.2, 10.3, 1.2, 7.2%, respectively) higher as compare to diesel. Further, it was observed that the ( NOx, CO, HC CO2, HC ) emission were found 15.6, 14.45, 45, 12.8% lower with B20A4 indicating potential of Bio diesel and DEE as supplementary fuel for diesel engine. Finally it was shown through wear analysis that use of blends of bio diesel and DEE results in no detrimental effect on engine life. Wear analysis shows that the maximum wear was found to be 63% lower in cylinder liner in case of B20A4 and reduction in weight was found to be 54.4% lower for compression ring.