硫对煤与五氯酚混烧过程二噁英生成影响规律的试验研究

Experimental Study of the Mechanism Regarding the Influence of Sulfur on the Formation of Dioxin during the Mixed Combustion of Coal and Pentachlorophenol (PCP)

二噁英是环境中的痕量剧毒有机污染物,对人类健康极具危害。本文以垃圾中的典型成份五氯酚(PCP)为研究对象,研究了煤和PCP混烧过程中,元素硫及煤中硫对烟气中二噁英生成的影响。煤的加入(特别是高硫煤的加入)可以明显降低二噁英生成。试验结果表明:煤和PCP混烧时,只要燃料中的S/Cl的摩尔比大于0.4时就能实现对燃烧过程中前驱物生成二噁英反应超过80%的抑制效率,当S/Cl比在0.7～1范围内的抑制效果较好。本文的实验结果对于探明实际垃圾焚烧过程中二噁英的生成机理和影响因素具有重要指导意义。

Minute traces of dioxin in the environment are considered a very poisonous organic pollutant and extremely hazardous to human health. With pentachlorophenol (PCP), a typical component in refuse, serving as an object of investigation the authors have studied the influence of element sulfur and sulfur in coal on the formation of dioxin in flue gas during the mixed combustion of coal and PCP. The adding in of coal, especially coal with a high sulfur content, can markedly reduce the generation of dioxin. The results of a test indicate that during the mixed combustion of coal and PCP, if S/Cl ratio in fuel is greater than 0.4, it is possible to achieve a suppression efficiency of over 80% for the precusor considered liable to generate a dioxin reaction. With the S/Cl ratio within the range of 0.7 1 there will be a relatively good suppression effectiveness. The test results are of great significance and can serve as a guide for identifying the dioxin generation mechanism and influencing factors in the process of refuse firing.