高含水率淤泥絮凝脱水影响因素试验研究

Experimental Study of the Factors Influencing Flocculation and Dehydration of High Moisture Content Sludge

为解决高含水率淤泥因孔隙小、渗透性差等导致脱水困难的问题,并为絮凝剂在高含水率淤泥脱水中的实际应用提供参考,通过单元抽滤试验,根据淤泥的比阻(specific resistance to filtration,SRF)、抽滤时间(time to filtration,TTF)、泥饼含水率(ω)、絮凝剂成本,通过模糊评价法确定适合淤泥脱水的絮凝剂种类,研究絮凝泥浆脱水效果的影响因素。试验结果表明,淤泥脱水的最佳絮凝剂为PAC(聚合氯化铝),相比未掺加絮凝剂的淤泥,掺加PAC后淤泥的最终排水量增加了75%,淤泥的泥浆平均比阻降低了72.9%,淤泥的泥饼含水率由75.7%降至52.9%,可见PAC具有显著的絮凝脱水效果。

In order to solve the problem of difficult dehydration of high water content sludge due to small pores and poor per-meability,and to provide reference for the practical application of flocculants in the dehydration of high water content sludge,unit filtration test was adopted,and based on factors such as specific resistance to filtration of sludge,time to filtration(TTF),water content of sludge cake and cost of flocculants,the fuzzy evaluation method was adopted to determine the types of flocculants suitable for sludge dehydration,and the influencing factors of the dehydration effect of flocculated mud were studied.The test results showed that the best flocculant for sludge dehydration was PAC(polyaluminum chloride).Com-pared with the sludge without flocculant,the final discharge volume of sludge with PAC increased by 75%,the specific resist-ance to filtration of sludge decreased by 72.9%,and the water content of sludge cake decreased from 75.7%to 52.9%.It can be seen that PAC has a significant flocculation and dehydration effect.