河道淤泥固化剂研发与机理探究

Research and Development of River Sludge Curing Agent and Its Mechanism

针对河道淤泥高含水率、低强度的问题,通过单掺实验及正交实验,向淤泥中添加硅酸盐水泥、粉煤灰、KPAM(聚丙烯酸钾)、磺化油等4种固化材料,以固化稳定后淤泥的含水率、无侧限抗压强度为评价指标,探讨淤泥固化剂的最优药剂配比。研究表明,单独使用硅酸盐水泥、粉煤灰、KPAM和磺化油对淤泥进行固化处理均有不同效果,但使用单一固化材料存在前期固化效果差、固化体增容大及固化成本高等问题。通过正交实验,得到前期固化减水效果最佳固化剂配比为5%硅酸盐水泥、6%粉煤灰、0.2%KPAM及0.15%磺化油;在养护时间达到55d时,使用该配比固化处理后的淤泥无侧限抗压强度为3.04 MPa,可满足填筑要求。固化处理后的淤泥重金属浸出实验显示,该复合固化剂对淤泥中的重金属有一定的稳定作用。利用SEM、XRD等观测分析淤泥内部结构,发现KPAM与磺化油的长链条作用使淤泥内部结构密实,水泥及粉煤灰与淤泥中水分产生的水化反应提升了固化淤泥的强度。

To solve the problem of high water content and low strength of river sludge, river polluted sludge was taken as the research object. Single mixing experiment and orthogonal experiment were carried out by adding four curing materials （Portland cement, fly ash, KPAM and sulfonated oil） in order to make sludge solidified. The moisture content and unconfined compressive strength of sludge after solidification and stabilization were taken as evaluating indicator to get the optimum composition of the sludge curing a fonated oil on the slu gen dge The study shows that the use of Portland cement, fly ash, KPAM and sul has different degrees of solidification effect, but the use of a single curing material faced with some problems, such as poor early curing effect, solidified body capacity increase, and high curing cost. Through the orthogonal experiment analysis, it is concluded that the best curing material ratio is 5% for Portland cement, 6% for fly ash, 0.2% for KPAM and 0.15% for sulfonated oil. When the curing time reaches 55 d, the unconfined compressive strength of the treated sludge is 3.04 MPa, and the filling requirement can be satisfied. The leaching experiment of heavy metals on the solidified sludge showed that the compound curing agent had a certain sta metals in sludge. By means of SEM and XRD, the internal structure of sludge is ing effect on heavy observed, and it is determined that the long chain effect of KPAM and sulfonated oil is the main cause of the internal structure of the sludge, and the hydration reaction of cement and fly ash and sludge is the main reason to enhance the strength of solidified sludge.