污泥焚烧无须顾虑尾气污染物

Unnecessary Worry about Pollutants in Off-gases of Sludge Incineration

剩余污泥处理/处置目前在我国似乎已成为比污水处理本身更为棘手的问题。为此,有关污泥处理/处置技术路线选择近年来成为热点话题。“扔”与“烧”两种极端处置方式因投资悬殊争议最大,但在“扔”已几近无路可走的情况下,污泥干化后焚烧不论是在能量平衡、基建投资还是运行费用等方面较其他选项已被确认为是一种终极选择。然而,国人“谈烧色变”,普遍认为除投资外,焚烧过程产生的二噁英、重金属以及NO”等尾气污染物可能危及环境与健康。对此,从二噁英等污染物在污泥焚烧过程产生原理出发,阐述它们的生成过程及其含量,论述对它们的控制与处理技术,并结合国内外排放标准审视国内污泥焚烧实例中尾气污染物排放浓度'最后,得出在焚烧过程中产生的二噁英等尾气污染物含量本来就不高,若辅以成熟的控制与处理技术,完全可以消除尾气泄漏以及健康威胁问题,并以发达国家相应技术报告作为佐证。

Disposal of excess sludge seems to has become a tougher problem than treating wastewater itself in China. For this reason, selecting routes of disposing sludge has been a hot topic in recent years. There are intense controversies in two extreme disposal measures of "throwing” and “burning” due to a big difference in investment. Under the condition where "throwing" approaches to a dead end, however, sludge incineration after drying have been identified as an ultimate option in terms of consideration of energy, investment and operation, compared to any other handling routes. Whatever, Chinese people are still terrified by such pollutants as dioxins, heavy metals and N0x in off-gases generated from incineration, which might endanger the environment and human health. Based on the generating principles of these pollutants, their formed processes and generated contents were elucidated;corresponding control/treatment techniques were reviewed;emission concentrations of the pollutants in off-gases were revealed, associated to the emission standards at home and abroad. After the review and discussion, the pollutants in off-gases could be thought to be small in their contents and could easily be controlled and/or removed by applied techniques, which should completely eliminate the excessively worry about leakage of off-gases and their threats on health , which was also proved by the developed countries corresponding technical reports about dioxins.