泥沙颗粒生长生物膜后沉降的实验研究Ⅰ：实验设计及粒径变化

Experiment on the biofilm effects on sediment settling Ⅰ.Experimental design and grading variation

天然河道与湖泊的水污染问题日益受到广泛的重视,对泥沙颗粒的基本特性的研究也开始与水体污染物质的吸附解析、微生物的吸附成膜等水环境生态方面结合起来。本文通过对官厅水库的泥沙分组进行培养,并采用先进的图像采集观测系统,对泥沙生长生物膜后的絮体在沉降时进行拍摄采集,探讨了颗粒级配的变化情况。同时利用得到的颗粒特征值,推导了水体不同营养条件下的粒径变化公式。数据表明泥沙在生物膜的作用下形成新的泥沙生物絮体颗粒,能够在水沙交界面上形成粒径范围很宽的颗粒组使得级配变化显著。

The pollution phenomena in rivers and lakes have attracted increasing attention on the combination of changes of sediment characteristics,processes of substance absorption-extraction,and also the microorganism colonization.A laboratory sediment settling experiment is set up to study the variations of bio-sediment particle distribution and settling movement.Experiments were performed on sediment particles obtained from the Guanting Reservoir by cultivating in certain groups,and the grading curves are presented from the experiments by particle image acquisition and image analyses.Data show significant changes of the particle distribution and sizes after the biofilm colonizing on sediment.A characteristic particle size formula is derived,in which the nutritional conditions are considered.