AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
Evaluating Elemental and Organic Carbon composition of Size-Segregated Combustion Particles Using the Electrical Low Pressure Impactor
PATRICIA FRITZ, Shida Tang, David Guerrieri, Brian P. Frank, Marilyn Wurth, Daniel Hershey, New York State Dept. of Environmental Conservation
Abstract Number: 86 Working Group: Instrumentation and Methods
Abstract The composition and morphology of aerosol particles continue to be poorly characterized with respect to their health impacts and their potential impact on atmospheric processes and climate forcing. Previously, we reported using a Combustion Aerosol Standard (CAST, Jing, Ltd.) system to generate emissions targeted to specific impactor stages of the Electrical Low Pressure Impactor (ELPI, Dekati, Ltd.) to describe particle size distributions in real time and to collect samples for development of post-sampling methodologies for morphological and chemical analysis. Manipulation of combustion parameters allowed precise control of both particle size (median particle diameters of 30, 109, or 267 nanometers) and loading on the stages.
In the current set of experiments we used the ELPI to measure particle concentrations and to collect particles on a series of stages to characterize elemental carbon (EC) and organic carbon (OC) content of emissions from different combustion aerosol sources (e.g. CAST and a Tier IV-compliant 14 kW diesel generator (Mitsubishi Corporation /Marathon Electric) and with different particle loadings. In addition to real-time data on particle size distributions, this method provides corresponding measurements of EC/OC ratios on a size-resolved basis. Evaluating the EC/OC ratio of emissions has been suggested as a tool for particulate source attribution and to estimate their potential influence on radiative forcing. Atmospheric EC and OC inputs are of interest to climate science due to their ability to absorb or reflect sunlight. These inputs are likely to increase with continued reliance on generators during storm and disaster recovery efforts, and with conversion of existing appliances and vehicles from petroleum and gas to biomass fuels.