Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Atmos. Chem. Phys., 16, 3449-3462, 2016
https://doi.org/10.5194/acp-16-3449-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
16 Mar 2016
Charging and coagulation of radioactive and nonradioactive particles in the atmosphere
Yong-ha Kim1, Sotira Yiacoumi1, Athanasios Nenes2,3, and Costas Tsouris1,4 1School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0373, USA
2School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332-0340, USA
3School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0100, USA
4Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6181, USA
Abstract. Charging and coagulation influence one another and impact the particle charge and size distributions in the atmosphere. However, few investigations to date have focused on the coagulation kinetics of atmospheric particles accumulating charge. This study presents three approaches to include mutual effects of charging and coagulation on the microphysical evolution of atmospheric particles such as radioactive particles. The first approach employs ion balance, charge balance, and a bivariate population balance model (PBM) to comprehensively calculate both charge accumulation and coagulation rates of particles. The second approach involves a much simpler description of charging, and uses a monovariate PBM and subsequent effects of charge on particle coagulation. The third approach is further simplified assuming that particles instantaneously reach their steady-state charge distributions. It is found that compared to the other two approaches, the first approach can accurately predict time-dependent changes in the size and charge distributions of particles over a wide size range covering from the free molecule to continuum regimes. The other two approaches can reliably predict both charge accumulation and coagulation rates for particles larger than about 0.04 micrometers and atmospherically relevant conditions. These approaches are applied to investigate coagulation kinetics of particles accumulating charge in a radioactive neutralizer, the urban atmosphere, and an atmospheric system containing radioactive particles. Limitations of the approaches are discussed.

Citation: Kim, Y.-H., Yiacoumi, S., Nenes, A., and Tsouris, C.: Charging and coagulation of radioactive and nonradioactive particles in the atmosphere, Atmos. Chem. Phys., 16, 3449-3462, https://doi.org/10.5194/acp-16-3449-2016, 2016.
Publications Copernicus
Download
Short summary
Three microphysical approaches are proposed to incorporate mutual effects of particle charging and coagulation in predictions of transient charge and size distributions of atmospheric particles, including radioactive aerosols. The three approaches have different levels of complexities and are applicable to various laboratory and field atmospheric studies. Also, these approaches can be easily incorporated into aerosol transport models at different scales to account for particle charging effects.
Three microphysical approaches are proposed to incorporate mutual effects of particle charging...
Share