利用成组生物测试评估不同深度处理工艺出水的安全性

Assessing the Ecological Risk of Effluents from Different Advanced Treatment Units by Using a Battery of Bioassay

针对北京北小河污水处理厂出水经深度处理后回用于奥运公园的生态安全性 ,用成组生物毒性测试方法比较了不同深度处理工艺对导致急性毒性的物质、内分泌干扰物质和Ah受体效应物质的去除效果 .结果表明 :城市污水厂出水中含有急性毒性、内分泌干扰和Ah受体效应毒性特征的污染物 ,超滤和活性炭对不同类型物质均有较好的去除效果 .活性炭吸附能基本有效去除具有急性毒性污染物 ,对Ah受体特征物质的去除率达到了 98% ;超滤对非极性、具有急性毒性特征的物质和极性的类雌激素物质去除效果最好 ,经超滤处理后的出水非极性组分细胞存活率达 10 0 % ,极性组分雌激素当量由 0 13pmol·L-1下降到 0 0 4 pmol·L-1.微滤和反渗透工艺不能有效去除有毒有机污染物 .进行生物毒性测试时 ,不同组分之间可能存在相互作用 ,需要采用样品分级方法 .

In this paper, effluents from different advanced treatment units, which were reclaimed for Olympic Park, were assessed regarding to the removal efficiencies of the technologies on acute toxicants, Ah-acceptor chemicals and estrogenic substances by using a battery of bioassays. The results showed that advanced treatments using ultra-filtration and activated carbon absorption were suitable for removal of toxic organic substances from STP effluent. Activated carbon absorption was the most effective technology to remove acute toxicants and Ah-acceptor chemicals, and the removal efficiency of Ah-acceptor chemicals reached 98%. Ultra-filtration was suitable for removing nonpolar acute toxicants and polar estrogenic chemicals. Nonpolar fraction extracted from water after ultra-filtration treatment showed 100% percentage survival of cell in the acute toxic assay. E2-TEQ was reduced from 0.13 pmol·L -1 to 0.04 pmol·L -1 in the polar fraction extracted from water after ultra-filtration. Treatments with micro-filtration and osmosis did not manifest sufficient efficiencies for removal of toxic organic substances. In complex matrix, interactions may occur among different toxic components to interfere the bioassay results. Therefore fractionation of organic concentrate before bioassay is necessary.