Investigation of sulfate nanoparticulate formation for a catalyzed diesel particulate filter on an engine fueled with ultre low sulfur diesel and a biodiesel blend

An off-road direct injection diesel engine equipped with a continuous-regeneration diesel particulate filter (DPF) was subject to two sets of experiments in which two fuels, ultra low sulfur diesel (ULSD) and 20 vol. % biodiesel blend (B20) were compared. In the first set of experiments lubricant oil consumption was measured by sulfur tracing. Results revealed a suggestive trend but not statistical confirmation of greater lubricant oil consumption with B20 fuel blend. In the second set of experiments nanoparticle formation downstream of the DPF was assessed. It was found that number concentration of nanoparticles released from the catalyzed DPF depends on fuel type and on engine operating condition and hence the onset of filter regeneration. For low soot loading times B20 fueling produces lower number concentrations, whereas longer soot loading times produce lower number concentrations with ULSD fueling.