New information about secondary particle formation from natural gas engine exhaust

Natural gas usage in the traffic and energy production sectors is a growing trend worldwide; thus, an assess ment of its effects on air quality, human health and climate

is required. Engine exhaust is a source of primary particulate emissions and secondary aerosol precursors, which both contribute to air quality and can cause adverse health effects.

The total mass of particles measured downstream of the PAM chamber was 6–268 times larger than the mass of the emitted primary particles. The aged particles consisted mainly of organic material, nitrate, sulfate and ammonium, their mass contributions depending on exhaust after-treatment and engine parameters. Engine operating mode, catalyst temperature and type also have impact on volatility and concentration of the total aged particles. The volatility of the total aged particles was lower than that of primary particles, suggesting that they were more stable in the atmosphere.

More information:

Researcher Sanna Saarikoski, sanna.saarikoski@fmi.fi

Alanen, J., Simonen, P., Saarikoski, S., Timonen, H., Kangasniemi, O., Saukko, E., Hillamo, R., Lehtoranta, K., Murtonen, T., Vesala, H., Keskinen, J., Rönkkö, T. Comparison of primary and secondary particle formation from natural gas engine exhaust and of their volatility characteristics. Atmos. Chem. Phys., 17, 8739–8755, 2017

https://www.atmos-chem-phys.net/17/8739/2017/acp-17-8739-2017.pdf