Emissions of volatile organic compounds from Chinese coal-fired power plants: Characteristics, source profile, inventories, and impacts

Abstract

Volatile organic compounds (VOCs) are key precursors for secondary organic aerosols (SOA) and ozone, imposing severe impacts on human health and environment. Considering the massive coal consumption, coal fired power plants (CFPPs) in China are non-negligible VOCs contributors, whose emission characteristics remain inadequately understood. Here, we investigated emission characteristics of 117 VOCs by field tests in four typical CFPPs, and a latest localized CFPPs source profile was compiled by integrating literature reviews. Then speciated-VOCs emission inventories for 2018–2022 were established based on dynamic emission factors and unit-level activity data. The results suggested that oxygenated VOCs (OVOCs) constituted the dominant group (76.5 %), with propionaldehyde (32.0 %) and formaldehyde (24.5 %) being the predominant species. OVOCs (93.2 %) and aromatics (77.4 %) were identified as the primary contributors to ozone and SOA, respectively. Driven by both the rise in coal consumption and technological advancements, nationwide VOCs emissions decreased from 83,393 t in 2018 to 53,251 t in 2022. Regional disparities and varying rates of decline in provincial emissions were evident, with VOCs emissions predominantly concentrated in northern and eastern provinces. Neimenggu, Shandong, Shanxi, Jiangsu, and Guangdong were identified as the top five provinces with the highest emissions. We believe this study would be conducive to a more comprehensive understanding and effective control of VOCs emissions from CFPPs in China.