Heavy metals and PAHs in sewage sludge from twelve wastewater treatment plants in China
Heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs) in sludges of twelve wastewater treatment plants (WWTPs) in Zhejiang province, China, were investigated in this research. The main objectives of the survey were to obtain basic data on the concentrations of HMs and PAHs in the sewage sludge and to assess their potential for land application. Concentrations of HMs in most of sludges were below the regulatory limits for the sludge to be used in agriculture in China (GB18918-2002) with the exception of Zn in two sludges and Cd in one sludge. All 16 PAHs, targeted by the USEPA agency, were found in most of the twelve sludges with total concentration ranging from 33.73mg kg<-1> to 82.58mg kg<-1> (d. w.). The levels of Σ9 PAHs varied from 13.87 to 61.86mg kg<-1> (d. w.) in these sludges and had far exceeded the limitation value recommended by the Europe Union. PAHs concentration and composition in sewage sludges varied and depended mainly on the quantity and type of industrial wastewater accepted by the WWTPs. A significant relationship, between the proportion of industrial wastewater received by WWTPs and the total content of 16 PAHs in sludge was observed. Results of this research indicated that PAHs have become one of the primary pollutants in sludges of Zhejiang WWTPs instead of HMs. It is, therefore, essential to reduce PAHs contents before the sludges could be permitted for agricultural use through proper treatment.
sludge heavy metal chemical fractions PAHs contribution
Li Hua Weixiang Wu Yuxue Liu Yingxu Chen
College of Environmental and Resource Science, Zhejiang University, HangZhou 310029, China
国际会议
北京
英文
226-241
2007-08-20（万方平台首次上网日期，不代表论文的发表时间）