市政污泥处理过程中全氟化合物浓度的变化趋势研究

Study on the changing trend of the concentration of perfluorinated compounds in the process of municipal sludge treatment

全氟化合物(PFCs)是具有毒性、持久性和累积性等性质的新型有机物,其广泛应用在多种产品的生产中,并且已经成为一种无处不在的全球性污染物。本文重点研究了在不同污水处理厂的剩余污泥高温好氧发酵过程中,全氟化合物(PFCs)的污染分布特征。采用高效液相色谱串联质谱联用技术,分析了沈阳市两个污水处理厂污泥中的PFCs的浓度、污染特征和污泥处理过程中PFCs的浓度变化趋势。结果表明,PFCs在污泥中被广泛检出。甲乙三个污水处理厂的污泥,在各个处理阶段中PFCs的总浓度范围分别为73.6~102ng·(g·dw)-1、11.2~39.7ng·(g·dw)-1。其中PFOS为两个污水处理厂的污泥中主要的PFCs污染物,其次是PFOA及其替代品PFBA。两个污水处理厂的污泥中PFCs的总浓度呈现增长趋势,这表明PFCs污染在污泥处理的各个阶段中累积增长,可能源于前驱物的转化。

Perfluorinated compounds(PFCs)are new organic compounds with the properties of toxicity,persistence and accumulation.They are widely used in modern production and have been a ubiquitous global pollutant.In this paper,the pollution distribution characteristics of perfluorinated compounds(PFCs)and their substitutes during high-temperature aerobic fermentation of residual sludge in different sewage treatment plants were studied.The concentration and pollution characteristics of PFCs and its substitutes in sludge of two sewage treatment plants in a city were analyzed by HPLC/tandem mass spectrometry.The results showed that PFCs and its substitutes were widely detected in sludge.The total concentration ranges of PFCs in the two sewage treatment plants are 73.63~102.98 ng/g dw,11.21~39.70 ng/g dw,respectively.PFOS is the main PFCs pollutant in the sludge of two sewage treatment plants,followed by PFOA and its substitute PFBA.The total concentration of PFCs and their substitutes in the sludge of the two sewage treatment plants showed an increasing trend,which indicated that PFCs accumulated and increased in each stage of sludge treatment,possibly due to the conversion of PFOS and other precursors.