VOCs Monitoring System Status and Development Direction in Key Regions of China

Scientific monitoring of volatile organic compounds (VOCs) in the atmosphere is the key basis for the formation mechanism and prevention and control of the combined pollution of O₃ and PM_2.5. It is of great significance to continuously improve the air quality in China. In order to optimize and improve the VOCs monitoring system and efficiency in China and put forward the development direction and path of photochemical monitoring in the future, the key elements of VOCs monitoring system design, monitoring sites, monitoring items and periods, monitoring technology and quality control technology at home and abroad are evaluated through research, data mining and other methods. This research is carried out from the development history, monitoring points, monitoring items and time periods, monitoring technology and quality of VOCs monitoring at home and abroad. The results show that: (1) China has initially established photochemical monitoring network covering key areas, but in the VOCs monitoring network, key points such as regions, transportation and high emission areas are lacking. It is important to optimize and improve the performance of VOCs monitoring network in China. (2) May to September is an important period of O₃ pollution in China. The components involved in Photochemical Assessment Monitoring Stations (PAMS) under the US Environmental Protection Agency (US EPA) aldehydes and ketones are important components affecting O₃, especially ethylene, benzene series, formaldehyde and acetaldehyde. And the impact of some branched chain olefins and natural source olefins such as α-pinene, and β-pinene on O₃ or particulate matters is also noteworthy. Finally, the monitoring project should be optimized according to the localization characteristics. (3) In terms of monitoring technology, manual monitoring and automatic monitoring have their own advantages, showing the development trend of automatic monitoring as the main and manual monitoring as the auxiliary. The monitoring technology system should be developed in the direction of high precision, standardization, miniaturization, modularization, intelligence, high time resolution and low monitoring cost. At the same time, quality system standard research should be continued to fill in the gaps and improve the quality of monitoring data. The research shows the monitoring points of atmospheric VOCs in China should be optimized, the standardization of monitoring technology system and quality system should be strengthened, and the localized monitoring projects in China should be formed focusing on key periods, so as to scientifically optimize and improve the photochemical monitoring program in China.