污水污泥及其浸出液重金属污染的化学分析与评价  

Chemical analysis and assessment of the heavy metal pollution in the sewage sludge and leaching solution

作　　者：李娟英[1] 陈洁芸[1] 沈燕萍 石恺柘[1] 郑健[1] 柯友章[1] 何培民[1] 

机构地区：[1]上海海洋大学水产与生命学院,上海201306 [2]上海市浦东新区河道管理署,上海201323

出　　处：《安全与环境学报》2013年第3期115-121,共7页Journal of Safety and Environment

基　　金：国家海洋局公益项目子课题(201105010-10);上海海洋生物重点学科项目(J50701)

摘　　要：对上海8个污水处理厂脱水后的污水污泥进行污泥常规指标、重金属总量与形态分析,并采用HJ 557—2010水平振荡法、NEN7341：1994法、USTCLP法和EN 12457-3：2002法对上述污泥湿样进行重金属浸出试验。重金属总量与形态分析结果表明：Zn和Cu在所有污泥样品中的总量都比较高,之后依次是Pb、As、Cd和Hg;Cd的4种不稳定形态的质量分数占70%以上,迁移性最强;Zn的不稳定形态占20%-50%;Cu主要以硫化物及有机结合态存在;Pb、Hg和As主要存在于残渣态中,最不易在环境中迁移。浸出试验结果表明：Zn的浸出量是6种重金属中最高的,其次是Cu和Pb,As、Hg和Cd的浸出量最低;在不同浸出方法中,NEN 7341：1994法对重金属的浸出量最多,US EPA的TCLP法和欧盟EN 12457-3：2002法大致相当,TCLP法对重金属的浸出量略多,而我国现行的水平振荡法对重金属的浸出量最少。在我国现行评价标准下,所有污泥样品均不属于具有浸出毒性特征的危险废物;但由于其浸出液中较高的DOC质量比,根据欧盟标准,其均属于具有浸出毒性特征的危险废物。The present article is engaged in a chemical analysis and assessment of the heavy metal pollution in the sewage sludge and leaching solution. For this purpose, we have analyzed in this paper the general characteristics aswell as the actual content and speciation of heavy metals in the dehydrated sludge samples from eight sewage processing plants in Shanghai with our leaching tests including HJ 557—2010, NEN7341： 1994, USTCLP and EN12457-3： 2002. The results of our analysis indicate that the total content of Zn and Cu in all the sludge samples are rather high, followed by Pb, As, Cdand Hg. Among the heavymetal contents, Cd reveals the highest degree of mobility from what is extracted in the water soluble. Cd also proves exchangeable, carbonate-precipitated and oxidation-bounded. It tends to be highly mobile and potentially bio-available, which therefore accounts for a high percentage （70%）. Of all the above four unstable fractions, Zn accounted for 20%-50%, which means that the considerable amount of Zn could be released to the liquid phase. Cu proves to be mainly present in the organic compoundswith sulfide and therefore poor in mobility. The results from our leaching tests also indicate that the leaching amount of Znwas the greatest and followed by Cu and Pb, with As, Hg and Cd being the least. It is more worthwhile commenting that the leaching test of NEN 7341： 1994 is the most attractive for its greatest leaching amount of heavy metals, followed by the other two roughly the same tests, that is, US TCLP and EN 12457-3： 2002, though HJ 557-2010 proposed by China proves to be the most gentle one. The difference among the above leachingtests is related tothe parameters of leachants, ratios of liquid to solid, oscillation modes and so on commonly adopted in the different tests. Though all the sludge samples were excluded from the hazardous wastes according to the current standard implemented in China, it remains logic and reasonable to categorize all the above samples into hazardous wastes for the ver

关 键 词：环境工程学 污水污泥 浸出液 重金属污染 评价 

分 类 号：X55[环境科学与工程—环境工程]