State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, Beijing 100085, China.
Environ Sci Technol. 2009 Dec 15;43(24):9196-201. doi: 10.1021/es902429m.
The coking process is considered to be a potential source of unintentionally produced persistent organic pollutants (UP-POPs). However, intensive studies on the emission of UP-POPs from the coking industry are still very scarce. Emission of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (dl-PCBs), hexachlorobenzene (HxCBz), and pentachlorobenzene (PeCBz) covered under the Stockholm Convention were investigated for the coking process in this study. Stack gases from some typical coke plants in China were collected and analyzed to estimate the emission of UP-POPs from the coking industry. Emission factors of 28.9 ng WHO-TEQ tonne(-1) for PCDD/Fs, 1.7 ng WHO-TEQ tonne(-1) for dl-PCBs, 596 ng tonne(-1) for HxCBz, and 680 ng tonne(-1) for PeCBz were derived based on the investigated data. The annual emissions from the global coking industry were estimated to be 15.8 g WHO-TEQ for PCDD/Fs, 0.93 g WHO-TEQ for dl-PCBs, 333 g for HxCBz, and 379 g for PeCBz, respectively (reference year 2007). According to the distribution of PCDD/Fs, we argued for the de novo synthesis to be the major pathway of PCDD/F formation. With regard to the characteristics of dl-PCBs, the most abundant congener was CB-118, and the most dominant contributor to the total WHO-TEQ of dl-PCBs was CB-126.
炼焦过程被认为是无意产生持久性有机污染物（UP-POPs）的潜在来源。然而，针对炼焦行业 UP-POPs 排放的深入研究仍然非常匮乏。本研究对《斯德哥尔摩公约》涵盖的多氯二苯并对二恶英/二苯并呋喃（PCDD/Fs）、类二噁英多氯联苯（dl-PCBs）、六氯苯（HxCBz）和五氯苯（PeCBz）等 UP-POPs 的排放情况进行了研究。本研究采集了中国一些典型炼焦厂的烟道气进行分析，以评估炼焦行业 UP-POPs 的排放情况。根据调查数据，计算出 PCDD/Fs 的排放因子为 28.9 ng 世卫组织-TEQ 吨(-1)，dl-PCBs 为 1.7 ng 世卫组织-TEQ 吨(-1)，HxCBz 为 596 ng 吨(-1)，PeCBz 为 680 ng 吨(-1)。据估计，全球炼焦行业每年排放 PCDD/Fs 为 15.8 g 世卫组织-TEQ，dl-PCBs 为 0.93 g 世卫组织-TEQ，HxCBz 为 333 g，PeCBz 为 379 g（参考年为 2007 年）。根据 PCDD/Fs 的分布情况，我们认为新合成是 PCDD/F 形成的主要途径。就 dl-PCBs 的特征而言，最丰富的同系物是 CB-118，对 dl-PCBs 总世卫组织-TEQ 贡献最大的是 CB-126。
