给水厂污泥脱水技术改造设计方案研究

针对以黄河水为原水的给水厂污泥进行了混凝及优选比阻调理试验,结果表明:当进行给水厂污泥脱水技术改造方案设计时,可以不经过混凝处理,直接利用电厂粉煤灰作为比阻调理剂。细粉煤灰的最佳投加率为20%,粗粉煤灰的最佳投加率为30%,使污泥比阻由1013数量级降至1010数量级,改善了污泥脱水性能,所得滤饼含水率仅为40%~50%,易于剥离,能耗低,所得滤液的色度、浊度、CODMn均达到可直接回用标准。当进行技改工程设计时,建议选用带式压滤机或板框压滤机,既适应粉煤灰调理剂,又可节约投资。

Research and design on waterworks sludge dewatering for reconstruction

The character of waterworks sludge is different from municipal wastewater sludge. Experiments of coagulation and optimal specific resistance conditioning processes were conducted on dewatering of waterworks sludge from raw water taken from Yellow River. The results showed that at the design stage it can be ignored the coagulation process and utilize fly ash of power plant directly as the conditioner. The optimum dosage of fine ash is 20%, and that of coarse ash is 30%. In that case, the orders of magnitude of sludge specific resistance can drop from 10~13 to 10~10 and the dewatering effect is improved. The water content of filter cake just ranges from 40% to 50%. The filter cake can be striped from filter media easily with low energy consumption. The color index, turbidity and COD_Mn of filtrate liquor can meet the direct reuse standard. It is better to choose belt press filter or plate-and-frame type press filter at design of a project of technical modification, this method not only fits the conditioner of fly ash, but also saves the investment.