Modeling semivolatile organic aerosol mass emissions from combustion systems
Manish K Shrivastava1, Eric M Lipsky, Charles O Stanier
1Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
Environmental Science & Technology
|May 11, 2006
Summary
This study models organic aerosol mass in diesel and wood exhaust, finding it
Area of Science:
- Atmospheric Chemistry
- Environmental Science
- Combustion Science
Background:
- Organic aerosols significantly impact air quality and climate.
- Understanding gas-particle partitioning is crucial for accurate emission modeling.
- Diesel and wood combustion are major sources of primary organic aerosols.
Purpose of the Study:
- To interpret experimental measurements of gas-particle partitioning and organic aerosol mass in diluted combustion exhaust.
- To develop and apply a two-component absorptive-partitioning model for emissions.
- To investigate the influence of atmospheric conditions on primary organic aerosol emissions.
Main Methods:
- Experimental measurements of gas-particle partitioning and organic aerosol mass.
- Fitting experimental data to a two-component absorptive-partitioning model.
- Simulating partitioning across a range of atmospheric conditions.
Main Results:
- Partitioning behavior of wood smoke and diesel exhaust can be modeled using two lumped compounds.
- Effective saturation concentrations were determined for these compounds.
- Primary organic aerosol mass shows significant variation with ambient temperature and background aerosol concentration.
Conclusions:
- Primary organic aerosol emissions are semivolatile and highly dependent on atmospheric conditions.
- Air quality models must treat primary organic aerosol as semivolatile.
- Dilution measurements provide insights but require careful interpretation relative to atmospheric conditions.
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