Formation of PCDDs and PCDFs in municipal waste incineration and its inhibition mechanisms: A review
Formation of PCDDs and PCDFs in municipal waste incineration and its inhibition mechanisms: A review
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DOI：
10.1016/s0045-6535(97)10048-0
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发表时间：
1998-03
期刊：
影响因子：
8.8
通讯作者：
K. Tuppurainen;I. Halonen;P. Ruokojärvi;J. Tarhanen;J. Ruuskanen
中科院分区：
文献类型：
--
作者：
K. Tuppurainen;I. Halonen;P. Ruokojärvi;J. Tarhanen;J. Ruuskanen
综述了多氯二苯并对二恶英（pcdd）和二苯并呋喃（pcdf）在城市生活垃圾（MSW）焚烧中形成的反应机理。详细探讨了一些可能的反应途径：例如高温热解，由大分子碳和存在于粉煤灰基质中的有机或无机氯低温重新生成，以及由不同的有机前体如氯酚生成。虽然所有这些机制都已经知道了很多年，但很少有详细的反应机制可以提供从大分子碳甚至结构密切相关的前体形成PCDD/F。相应的反应往往只是小的副反应，产率低。这主要是由于粉煤灰基质的极端复杂性，它有效地模糊了活性催化位点和整个过程的身份。本文讨论了PCDD/F的产生以及过渡金属和芳香前体之间的相互作用与城市生活垃圾焚烧中PCDD/F排放量的关系。然后讨论了过渡金属与城市垃圾焚化炉中PCDD/F排放之间的关系。通过文献调查和一些热力学考虑，可以得出关于烟气和颗粒中过渡金属负荷、PCDD/F浓度和操作温度之间关系的结论。并简要讨论了几种可能的缓蚀机理及其热力学。
The reaction mechanisms by which polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) form in municipal solid waste (MSW) incineration are reviewed. Some of the possible reaction pathways are explored in detail: e.g. high-temperature pyrosynthesis, low-temperature de novo formation from macromolecular carbon and organic or inorganic chlorine present in the fly ash matrix, and formation from different organic precursors such as chlorophenols. Although all these mechanisms have been known for a number of years, few detailed reaction mechanisms can yet be offered for PCDD/F formation from macromolecular carbon or even structurally closely related precursors. The corresponding reactions are always only minor side-reactions with low yields. This is due in particular to the extreme complexity of the fly ash matrix, which effectively obscures the identity of the active catalytic sites and the overall processes. This work discusses the production of PCDD/Fs and the interactions between transition metals and aromatic precursors in relation to the amount of PCDD/F emitted in MSW incineration. It then goes on to discuss the correlation between transition metals and PCDD/F emissions in MSW incinerators. A literature survey and some thermodynamic considerations allow conclusions to be drawn on the relations between the loading of transition metals in flue gases and particles, PCDD/F concentrations, and operating temperature. Some possible inhibition mechanisms and their thermodynamics are also discussed briefly.