College of Environmental Science and Engineering, Laboratory of Compound Air Pollutions Identification and Control, Taiyuan University of Technology,Taiyuan, 030024, China; Institute of Nuclear Environmental Science, China Institute for Radiation Protection, Taiyuan, 030006, China.
College of Environmental Science and Engineering, Laboratory of Compound Air Pollutions Identification and Control, Taiyuan University of Technology,Taiyuan, 030024, China.
Environ Pollut. 2023 Oct 15;335:122373. doi: 10.1016/j.envpol.2023.122373. Epub 2023 Aug 12.
Coking plants in China generate a substantial amount of volatile organic compounds (VOCs). The emission factors (EFs) of VOCs from coking plants are not well known, and thus, this study characterized the VOCs in the emissions from four coking plants in Shanxi, China. The EFs of VOCs from different stages of the coking process were calculated, and coal charging exhibited the highest EFs of VOCs, followed by the flue gases from combustion of coke oven gas, wastewater treatment, coke pushing and chemical byproduct recycling. The VOCs in emissions differed by coking process. Alkanes, aromatics and alkenes were the main VOCs emitted during the coking, wastewater treatment and chemical byproduct recycling processes, respectively. To effectively control the contribution of VOCs from coking processes to secondary organic aerosols and ozone formation, attention should be given to wastewater treatment and coal loading processes. The mean annual weight of VOCs emitted from coking plants in China from 2019 to 2021 was estimated to be 32.91 Gg with coking, chemical byproduct recycling, and wastewater treatment processes accounting for 91.34%, 7.85%, and 0.80% of total VOCs, respectively. An uneven spatial distribution of VOCs emissions in China was identified, with Shanxi, Shaanxi, Hebei, Inner Mongolia and Shandong being the largest contributors.
中国的焦化厂会产生大量挥发性有机化合物（VOCs）。焦化厂 VOCs 的排放因子（EFs）并不为人所知，因此，本研究对中国山西的四家焦化厂排放的 VOCs 进行了特征描述。计算了焦化过程不同阶段 VOCs 的排放因子，装煤阶段的 VOCs 排放因子最高，其次是焦炉煤气燃烧产生的烟道气、废水处理、推焦和化学副产物回收。排放的 VOCs 因焦化工艺而异。在炼焦、废水处理和化学副产物回收过程中，分别排放出主要的 VOCs，分别为烷烃、芳烃和烯烃。为了有效控制焦化过程 VOCs 对二次有机气溶胶和臭氧形成的贡献，应注意废水处理和装煤过程。据估计，2019 年至 2021 年中国焦化厂每年排放的 VOCs 平均重量为 32.91 Gg，其中炼焦、化学副产物回收和废水处理过程分别占总 VOCs 的 91.34%、7.85%和 0.80%。确定了中国 VOCs 排放的空间分布不均匀，山西、陕西、河北、内蒙古和山东是最大的排放源。
