粉煤灰改性及钝化污泥实验研究

Modification and Application of Fly Ash for the Stabilization of Sludge

以粉煤灰和石灰石为原料,加入一定量矿化剂,在微波辐照下进行改性,得到吸附材料粉煤灰沸石(FZ),通过X射线衍射和电镜扫描等方式对粉煤灰辐照改性原理及产物结构等进行了分析,通过添加不同比例的粉煤灰对城市污泥进行了钝化实验研究,并对钝化作用机理进行了分析,对钝化污泥中重金属含量变化及养分含量进行了测试,实验结果表明,改性粉煤灰对污泥中含重金属Zn、Cu、Mn具有明显钝化作用,对污泥中养分具有良好的滞留效果,经钝化处理后,污泥中重金属Zn、Cu、Mn含量都显著低于国家农用标准,污泥渗滤液中全氮含量低于中国地面水环境质量标准(10 mg.L-1),全磷含量低于污水排入城市下水道水质标准(1 mg.L-1)。

Under the microwave irradiation, a highly effective adsorptive material- zeolitized fly ash （FZ） was made by adding a certain amount of mineralizer in the raw material of the limestone and fly ash. The structure of zeolite and the mechanism of modification were investigated by the analysis of XRD and SEM. The stabilization mechanism was analyzed and the variation of heavy metals and nutrient contents in sewage sludge were investigated through the sludge stabilization experiment by mixing zeolitized fly ash in the municipal sewage sludge. It was indicated that the zeolitized fly ash had obvious stabilization effect to heavy metals （Zn,Cu,Mn） and had apparent retention ability to the nutrients contents of N,P of the municipal sewage sludge. The heavy metals contents of Zn, Cu and Mn were all significant lower than those in the national control standards for pollutants in sludges from Agricultural. After the stabilization treatment of the municipal sewage sludge, the total content of N was lower than that in the national surface water environmental quality standards （10 mg/L）, the total content of P was lower than that in Quality Standard of the Sewage discharged into the city sewer system（1 mg/L）.