添加剂对脱水污泥中重金属形态的影响

Effect of Additive on Heavy Metal Speciation in Dewatered Sludge

采用不同添加剂与污水处理厂的脱水污泥进行混合填埋,考察了填埋初期和后期污泥中重金属形态的变化。结果表明,添加生石灰、粉煤灰和粘土均有利于Cr和Cd向稳定形态转化;添加生石灰有利于Pb和Zn向稳定形态转化,而添加粉煤灰和粘土则有相反作用;添加生石灰、粉煤灰和粘土均会促使Cu向不稳定形态转化;添加粉煤灰有利于N i向稳定形态转化,而添加生石灰和粘土则起到了相反的作用。

The dewatered sludge was added with various additives to be landfilled, and the variation of heavy metal speciation in sludge during initial and final landfill stages was investigated. The results show that the additions of quicklime, coal ash and clay favor the stabilization of Cr and Cd. The addition of quicklime favors the stabilization of Pb and Zn. However, the additions of coal ash and clay have a reverse effect on Pb and Zn stabilization. The additions of quicklime, coal ash and clay accelerate the instabilization of Cu. The addition of coal ash favors the stabilization of Ni. However, the additions of quicklime and clay have a reverse effect on Ni stabilization.