[Ozone Generation Potential and Highly Contributing Substances of NMOCs from Landfill Working Face]

Non-methane organic compounds (NMOCs) are major ozone precursors in atmospheric photochemical reactions. The working face of a landfill is a significant source of fugitive NMOC emissions. In order to control tropospheric ozone pollution, it is necessary to minimize NMOCs, and this requires identification of contributing substances. In this study, gas samples were collected from the working face of a landfill and analyzed. Their ozone formation potential was calculated using the propylene-equivalent concentration method and the maximum incremental reactivity method. In total, 36 kinds of substances met the standard for detection frequency and concentration. The average annual concentration of NMOCs was about 10000 μg·m^-3, with total concentration greatest in summer. Concentrations of materials were as follows:oxygenated compounds > sulfur compounds > halogenated hydrocarbons > benzene series > hydrocarbons. Based on the results of the two calculation methods, ethanol, m-xylene, propylene, ethyl acetate, and n-pentane were found to be significant ozone formation contributors across the whole year. The pattern for spring was similar. Contributors to high ozone formation were ethanol, 1-butene, toluene, cyclohexane, and styrene in summer and spring, while ethanol contributed very significantly in winter. The propylene-equivalent concentration method was found to be more suitable for estimating ozone formation potential from the working face.