Simultaneous reduction of NO–smoke–CO2 emission in a biodiesel engine using low-carbon biofuel and exhaust after-treatment system

Abstract

The present work focuses on the simultaneous reduction of NO–smoke–CO2 emission in a Karanja oil methyl ester (KOME)-fueled single-cylinder compression ignition engine by using low-carbon biofuel with exhaust after-treatment system. Replacement of KOME for diesel reduced smoke emission by 3% but resulted in increase of NO emission and CO2 emission by 13 and 35% at 100% load condition. In order to reduce CO2 emission, tests were conducted with a blend of KOME and orange seed oil (OSO), a low-carbon fuel on equal volume basis (50–50). At the same operating conditions, compared to KOME, 27% reduction in CO2 emission and 5% reduction in smoke emission were observed. However, a slight increase in NO emission was observed. To achieve simultaneous reduction of NO–smoke–CO2 emissions, three catalysts, namely monoethanolamine, zeolite and activated carbon, were selected for exhaust after-treatment system and tested with optimum KOME–OSO blend. KOME–OSO + zeolite showed a great potential in simultaneous reduction of NO–smoke–CO2 emissions. NO, smoke and CO2 emissions were simultaneously reduced by about 15% for each emission compared to diesel at 100% load condition. The effect of exhaust after-treatment system with KOME–OSO blend on combustion, performance and other emission parameters is discussed in detail in this study. Fourier transform infrared spectrometry analysis and testing were done to identify the absorbance characteristics of zeolite material.