AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Primary and Secondary Aerosols from a Non-road Diesel Engine and the Role of Alternative Fuels and After Treatment
SHANTANU JATHAR, Abril Galang, Patrick Brophy, Beth Friedman, Gregory Schill, Paul DeMott, Delphine Farmer, Sonia Kreidenweis, Anthony Marchese, Daniel Olsen, John Volckens, Colorado State University
Abstract Number: 583 Working Group: Primary and Secondary Aerosols from Agricultural Operations
Abstract Non-road diesels, as used on agricultural and construction vehicles amongst many other, account for about a quarter of the nitrogen oxides and primary aerosol emissions from mobile sources in the United States. While a lot is understood about primary emissions, very little work has been done to characterize the atmospheric formation and evolution of secondary aerosols from non-road diesel engines. Further, little is understood about how secondary aerosols respond to the use of alternative fuels and after treatment devices. To address this gap, we will perform experiments on diluted emissions from a Tier 3 4.5 L John Deere tractor diesel engine and simulate atmospheric photochemistry on those emissions using a potential aerosol mass (PAM) reactor. The PAM reactor will be used to simulate photochemical ages between three hours and seven days. Aerosol size, mass and composition will be collectively measured using a scanning mobility particle sizer, photoacoustic extinctiometer, single particle soot photometer and high resolution aerosol mass spectrometer. The ice-nucleating capability of the aerosols will be measured using a continuous flow diffusion chamber. The potential of the aerosols to form reactive oxygen species (a proxy for the toxicity of aerosols) will be measured by collecting aerosols on filters and performing a dithiothreitol chemical assay offline. In this talk, we will communicate our findings on primary aerosol emissions and secondary aerosol formation and discuss the findings in light of their climate- and health-relevant implications. Furthermore, we will also describe how the aerosol system responded to the use of soy-based biodiesel (B100) and the inclusion of a diesel particulate filter, diesel oxidation catalyst and selective catalytic reduction unit.