厦门市污水处理厂污泥重金属含量分析

Analysis on the Content of Heavy Metals in Sludges of Municipal Sewage Treatment Plants in Xiamen City

为解决污泥的出路问题,对厦门市6座城市污水处理厂污泥中的重金属种类和数量进行了连续4年的监测和分析。结果表明,厦门本岛污水处理厂污泥的成分比岛外的简单;污泥中主要含有重金属Ni、Cr、Zn、Cd、Cu,毒性较大的元素Hg、As和Pb的含量较低;本岛和岛外各厂污泥中Ni、Zn和Cd的含量普遍较高,均超出《城镇污水处理厂污染物排放标准》(GB18918—2002)中污泥农用标准限值(土壤pH<6.5),岛外污泥中的Cr和Cu也超出农用标准;除岛外部分污泥中Cu和Ni的含量有增加外,其它重金属元素的含量均呈下降趋势。

To resolve the outlet problem of sludges, lots of experiments were carried out to measure the categories and amounts of heaw metals in sludges of six municipal sewage treatment plants in Xiamen City for four years. The result showed that sludges composition of the cent island was simpler than that outside of the island. Sludges in Xiamen City mainly contained Ni, Cr, Zn, Cd, Cu, while concentrations of high toxic metals, Hg, As and Pb, were lower. The contents of Ni, Zn and Cd were all high in sludges, and all exceeded the limit values of the national control standard for agriculture reuse, China Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant （GB18918-2002, soil pH〈 6.5）. The contents of Cr and Cu were also high in sludges outside of the island, and exceeded the national control standard too. There was a decreasing trend for heavy metals in sludges in Xiamen City except some of contents of Cu and Ni increased outside of the island.