电解质对细颗粒泥沙絮凝影响的试验研究

Experimental research of electrolytic effect on fine sediment flocculation

在影响泥沙絮凝的因素中,电解质的影响是主要的,也是复杂的。为了研究电解质对泥沙絮凝的影响,取用长江口的细颗粒泥沙置于不同阳离子浓度的天然海水、人工海水、NaCl溶液和MgCl2溶液中,并测量泥沙Zeta电位,分析其沉降速度,研究电解质种类和浓度与细颗粒泥沙絮凝的关系,并利用扫描电子显微镜观察絮凝体,从微观角度进一步验证实验结论。研究发现,电解质种类和浓度均会影响泥沙颗粒的Zeta电位,而且细颗粒泥沙Zeta电位绝对值越小,其絮凝现象越明显。

Among the influential factors to sediment flocculation, electrolyte is a main one and its influence is complicated. To research the influence of electrolyte on sediment flocculation, the fine sediment at the estuary of Yangtze River was sampled and put into natural sea water, artificial sea water, NaC1 solution and MgC12 solution to measure Zeta potential of the sediments and analyze the settlement velocity and the relation between fine sediment flocculation and electrolyte classification and concentration. In the test, scanning electron microscopy was used to observe the flocs and verify the test conclusions from microscopic point. The analysis results show that the classification and concentration of electrolyte can influence the Zeta potential of the sediment; the smaller the absolute value of fine sediment is, the more obvious of the flocculation phenomena.