Characterization and Exhaust Emission Analysis of Biodiesel at Different Temperatures and Pressures: Laboratory Study

Abstract

Soybean biodiesel with blends of B05 [5% biodiesel, 95% ultra-low-sulfur diesel (ULSD) or B00] and B20 (20% biodiesel and 80% ULSD) and ULSD were combusted in a closed chamber at 260 and 290°C (500 and 550°F) and 2.0 and 2.4 MPa (300 and 350 psi). B05 and B20 were selected because they are the most common biodiesel blends and very little has been reported on the emission compositions of these blends under various combustion conditions. CO, CO2, and CH4 emissions and elements of particulate matter (PM) were analyzed. CO2 emissions from B20 were more sensitive to temperature changes at low pressure. For both B00 and B20, decreases in the CO concentration were observed when combusted at high temperature and pressure. An increase in biodiesel blends appeared to reduce CO and increase CO2 emissions. For all the samples tested, the concentrations of Al, Ca, Cr, Na, S, and Si were higher than those of other elements in PM. The PM element concentrations founds in both B00 and B20 emissions were almost the same, except for Cu, Ga, and K, which were observed in high concentrations in B20 combustion.