Real-time tracing VOCs, O3 and PM2.5 emission sources with vehicle-mounted proton transfer reaction mass spectrometry combined differential absorption lidar

Abstract

Owing to rapid economic development and urbanization, environmental problems caused by PM2.5 and O3 have been occurring frequently. Volatile organic compounds (VOCs) are significant precursors of O3 and secondary organic aerosols that contribute to PM2.5. The study of VOC pollution characteristics is of great significance for providing a reference to guide its reduction policy formulation. Proton transfer reaction mass spectrometry has been widely used to study the emissions, distributions, and chemical evolution of VOCs in the atmosphere. A differential absorption lidar is often used to detect O3 concentration profiles and aerosol extinction coefficient profiles in low troposphere. In this study, a novel vehicle-mounted differential absorption lidar combined with a PTR-MS system is used to track environmental VOCs, particulate matter and O3 emission sources in real time. Plane scanning results can determine the contaminated areas on a large scale. The results of particulate matter navigation and fixed vertical detection both showed that local pollution and high-altitude input pollution together lead to poor air quality. Navigation experimental results show that the pollution sources are mainly concentrated in the vicinity of traffic intersections, polluting enterprises and residential areas. O3, particulate matter and VOCs have the same high value region.