植被过滤带中胶体颗粒物沉积过程的多尺度研究

项目名称： 植被过滤带中胶体颗粒物沉积过程的多尺度研究

项目编号： No.51509069

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 其他

项目作者： 庾从蓉

作者单位： 河海大学

项目金额： 20万元

中文摘要： 面源污染是我国水体环境恶化的主要原因之一，其中胶体颗粒物是面源污染物的重要组成部分。他们有些自身是污染物质，其他由于其比表面积大，可携带其他污染物质运移。植被过滤带是解决农业面源污染中溶质与泥沙问题的有效技术手段。胶体颗粒物在植被过滤带中的去除及运移机理研究对于面源污染控制意义重大。本项目拟以多孔介质的经典胶体过滤理论为基础,通过室内实验以及数值模拟技术，研究胶体颗粒物在植被过滤带上受水动力、水化学环境的影响作用，进而探讨沉积发生机理，建立沉积系数的表达式。同时，针对野外尺度下物理化学条件的不均一性，通过野外实验以及数值模拟，建立沉积表达式从实验室到野外的尺度效应关系。研究结果对理解植被过滤带的污染净化有理论指导意义，可以为其物理模型参数选取提供理论依据，为高效利用植被过滤带减轻面源污染提供技术支持。

中文关键词： 沉积过程；尺度效应；迁移过程；胶体颗粒物；浓密植被

英文摘要： Non-point source pollution is one of the key reason that the water quality deteriorate in China. Colloid particles, one kind of suspended particle whose diameter is less than 10 um, are important components of the non-point source pollutants. They can be contaminants themselves, or become contaminants due to the large surface area ratio when they facilitate the transport of the contaminants. Vegetative filter strips (VFS) are commonly used techniques to remove the solute and sediment from the non-point source pollution, but the removal efficiency and the transport mechanism of colloid particles in VFS are poorly understood. This proposed study will focus on the deposition mechanism of the colloid particle transport process, which is different mechanism from solutes and sediments in the VFS. Laboratory experiments will be employed to investigate the flow dynamics and water chemistry impact on the deposition of colloid particles, and further derive the mathematics expression for the deposition process. Considering the physical-chemical heterogeneity between the lab and field condition, field experiment and mathematical model are employed to investigate the scaling effect. The research output can provide technical support for the design of the VFS, and also provide the theoretical references for the parameter selection of future physical models for wetland and VFS design, which both are important measurements for non-point source pollution control.

英文关键词： deposition ;scaling effect;fate and transport;colloidal particles;dense vegetation