Segments-based Volatile Organic Compounds Emission Characteristics from Different Type Coking Plants in China

ABSTRACT The source profiles, emission factors, and chemical reactivity of volatile organic compounds (VOCs) were determined for different emission segments during regular plant operation of non-recovery and mechanical coking plants in Shanxi province, a typical coking plant centralized area in China. Ethylene, 1-butene, benzene, acetylene, and 2,2-dimethylbutane were the major components emitted from the stack flue gas of non-recovery coking segment, whereas styrene, benzene and ethylene were the most abundant components emitted from stack flue gas of mechanical coking segment. Regarding fugitive emissions, benzene, toluene, ethane, m-xylene, and ethylene were the most abundant species from coke oven leakage, whereas byproduct plant leaks in mechanical coking plant were predominantly benzene, propane, ethane, ethylene, n-pentane, n-butane, isobutene, 1-butene, toluene and propylene. VOCs emission factors of the stack flue gas were 96 g·Mg-1 coke and 0.4 g·Mg-1 coke for non-recovery and mechanical coking plants, respectively; thus, VOCs emissions from non-recovery coking plants are of greater concern. The ozone formation potential of stack flue gas in non-recovery coking plant was the highest (80.26 mg·m-3), followed by that of coke oven fugitive emissions in mechanical coking plants (7.22 mg·m-3); therefore, controlling these emissions would significantly reduce ozone conversion by VOCs from coking plants. In conclusion, replacing non-recovery coking plants with mechanical coking plants will help reduce the VOCs emissions and improve ambient air quality in China.