Characterization of the Particle Emissions from Diesel Transit Bus Equipping Diesel Particulate Filter with Fuel Burner

Abstract

On-road particle emissions were tested in urban areas of Shanghai from a diesel bus equipping diesel particulate filter with fuel burner. EEPS 3090 particle analyzer was used for analyzing concentrations of particles in different diameters. In this paper, characterization of particles in soot loading and regeneration processes were identified, and particle reduction ability of DPF bus was analyzed. Result shows that, the averaged particle emission rate from DPF bus was degraded by 1 to 2 orders of magnitude during soot loading. Particle concentration distribution was transformed from nuclei-accumulated bi-modal pattern to uniformly multi-peaks patterns. In DPF regeneration process, particles of accumulated mode sized between 60.4nm and 107.5nm were decomposed and oxidized into fine nuclei particles of 29.4nm to 60.4nm, which increases total particle concentration. Reduction percentage of particle number per kilometer of DPF bus for soot loading and regeneration process reaches respectively 97% and 83.2% compared with normal diesel bus.