高含沙浑水在絮凝剂作用下的絮凝沉降试验研究

电厂净化站排出的泥水加入高分子聚丙烯酰胺(PAM)絮凝剂后,改变了泥沙颗粒的自然沉速。通过试验找到净化站排向沉淀浓缩池的浑水含沙量、加药量、加药泥沙沉淀的时间及絮凝沉速之间的关系,从而为净化站的泥沙沉淀浓缩池运行提供最优的排泥方案。泥沙混凝静沉试验研究结果表明:不同含沙量的泥沙沉速并不是与加药量成正比,而是存在一个使泥沙沉降最快的最佳加药量;这一最佳加药量随着泥水含沙量的增加而增加;并且每增加单位含沙量所对应的加药量相对有所减少。模型中的高含沙浑水动沉絮凝沉降试验结果表明,其最佳加药量与室内絮凝静沉试验的加药量相一致。

Experimental research on flocculated sediment settling in high sediment-contents under flocculating admixture

In order to increase the falling velocity of sediment particles in the muddy water discharged from a clarification station of a coal-fired power station,polyacrylamide(PAM) was added into the muddy water.The main objective of the experiment was to find the relationship among sediment concentration,amount of PAM,sediment settling time and sediment flocculated falling velocity.Through experiments,an optimum operation scheme for discharging sediment to the clarification station has been achieved.The experimental results showed that falling velocities of sediment particles at different sediment concentrations are not in direct proportion to the amount of PAM.In other words,there is an optimum value of PAM,at which the settling velocity is the largest.The optimum value increases with the increasing of sediment concentration,but the unit increase in PAM with the unit increase in sediment concentration decreases.