Compositional Analysis of Biodiesel Particulate Matter (BPM) from a Non-Road Diesel Generator

There have been multiple studies of biodiesel particulate matter (BPM) emissions over the years, but few are on non-road diesel engines despite their higher emissions and less regulation. The goal of this paper is to further investigate the impacts of biodiesel fuel on particulate matter emissions. Compositional analysis of BPM was performed on a non-road diesel generator under various loads using different diesel and biodiesel blends. In order to account for organic compositions from both petroleum diesel and biodiesel, two types of analytical columns were used, one for polar compounds such as fatty acid methyl esters (FAME) and another non-polar column for hydrocarbons and PAHs (polycyclic aromatic hydrocarbons). In the BPM emitted, FAME constituted 6% to 11% of the total mass at different loads, which is the highest among the soluble organic fractions. This is an indication that biodiesel fuel might not be completely combusted in this diesel engine. The PAH fraction of the B50 (50% biodiesel) is much less than that found in petroleum diesel PM (B0). The elemental carbon fraction of the B50 particulate matter is less than that from B0. The lower PAH and soot from biodiesel blends may correspond to lower toxicity.