北京市污水处理厂中邻苯二甲酸酯污染水平及其归趋

Occurrence and Fate of Phthalates in Wastewater Treatment Plants in Beijing,China

选取北京市3个污水处理厂为研究对象,采集进厂水、二沉出水和出厂污泥并分析其中的邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸丁基苄基酯(BBP)、邻苯二甲酸二正辛酯(DOP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)浓度.进厂水水相中DMP、DEP、DBP和DEHP的平均浓度分别为0.98、0.21×102、0.27×102和0.15×102μg.L-1,而BBP和DOP均未检出.脱水污泥中检出了DBP和DEHP,平均质量浓度(以干重计)分别为0.37μg.kg-1和0.31×103μg.kg-1.DMP、DEP、DBP和DEHP的去除效率分别为68.3%～82.6%、94.5%～98.2%、74.7%～95.0%和90.5%～90.7%,主要的去除机制可能是生物降解和向空气挥发.而二沉池出水和脱水污泥中高浓度的DBP和DEHP值得关注.

Three waste water treatment plants（WWTPs） in Beijing were selected as cases to study the occurrence and fate of phthalates.Contents of di-methyl phthalate（DMP）,di-ethyl phthalate（DEP）,di-butyl phthalate（DBP）,butyl-benzyl phthalate（BBP）,di-octyl phthalate（DOP） and di-（2-ehtylhexyl） phthalate（DEHP） in influent,effluent of secondary setting tank and excess sludge in those WWTPs were determined.The mean concentration of DMP,DEP,DBP and DEHP are 0.98,0.21×102,0.27×102 and 0.15×102 μg·L-1 respectively.BBP and DOP were not found in those WWTPs.Only DBP and DEHP were detected in dewatered sludge with mean concentration of 0.37 μg·kg-1 and 0.31×103 μg·kg-1 DW.The removal efficiency of DMP,DEP,DBP and DEHP varied from 68.3%-82.6%,94.5%-98.2%,74.7%-95.0% and 90.5%-90.7% respectively.The main removal mechanism should be biodegradation and volatilization to the air.Higher concentration of DBP and DEHP in effluent and dewatered sludge should be concerned.