Abstract View
The Role of Oxidizer Concentration, Fuel Consumption Rate, and Dilution Conditions on Near-source Aerosol Emissions from Lignocellulosic Biomass and Constituent Burning
LUKE MCLAUGHLIN, Erica Belmont, University of Wyoming
Abstract Number: 546
Working Group: Combustion
Abstract
The majority of global primary organic aerosol (POA) emissions are produced from biomass burning (BB), and POA are understood to have negative impacts on humans and the environment. POA emissions have a broad range of physical properties, such as particle size, quantity, and volatility, and these properties are closely related to near-source burning conditions. The properties of POA are difficult to predict due to the natural complexities of BB, including variability in near-source burning conditions such as oxygen availability, fuel consumption rate, and dilution gas temperature. In this work, aerosol emissions were measured in a controlled laboratory setting from burning of lignocellulosic biomass and major lignocellulosic biomass constituents in inert and oxidative environments to better understand the influence of fuel composition, dilution conditions, and oxygen availability on the number and size of aerosols formed during BB. Fuel mass and fuel consumption rate were also investigated for their influence on aerosol emissions, and an aerosol volatility assessment was performed. A summative model for aerosol emissions prediction from BB was developed and tested, and results were compared to experimental measurements from woody and herbaceous biomass samples. Results showed significant influences of fuel type, oxygen availability during burning, and dilution conditions on the number and size of aerosols formed, and nucleation mode particles dominated the emissions in all of the conditions investigated here. Absolute fuel consumption rate increased with increased reaction environment oxygen level and fuel mass, and aerosol size positively correlated with fuel consumption rate. The summative model predicted number emissions for biomass pyrolysis and combustion and mass emission factors for biomass combustion well. However, the model less successfully captured the measured mass emission factors for biomass pyrolysis. The applicability of the proposed model and reasons for the discrepancies between the model and experiments were investigated in this work.