混凝-气提-超滤膜内多相流耦合作用机制及膜滤效能的研究

项目名称： 混凝-气提-超滤膜内多相流耦合作用机制及膜滤效能的研究

项目编号： No.51278317

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 建筑科学

项目作者： 刘百仓

作者单位： 四川大学

项目金额： 80万元

中文摘要： 采用膜组合处理技术可以不同程度的改善膜的性能。各种组合处理工艺中，混凝-膜滤目前是控制膜污染及提高水质处理效果的有效方法。但该工艺实际运行中存在部分絮体滞留时间过长，有机物从絮体上脱附致使水质变差，滤饼层长期形成后会质密通量减小且难以清洗。因此，本研究采用新型的组合工艺混凝-气提-超滤膜，以该工艺内气泡、絮体、水多相流相互作用机理及膜的效能为研究的核心，以期达到经济节能的运行和高的水质处理效率。通过对气泡上升速度与浓度（间歇或连续）、混凝条件、稳定或脉动流、跨膜压差等参数的控制，实现混凝-气提-超膜滤技术的有机组合。拟采用自动化模型控制系统，通过仪器分析絮体尺寸分布、分形维数，气泡速度、浓度，膜表面污染层的阻力变化，膜表面水力剪切力，水质参数等，将膜性能分析与多相流耦合作用机理分析相结合，进行系统性实验。以提高水质处理效果和控制膜的制水成本为目标，提出优化运行与控制策略。

中文关键词： 多相流；膜性能；气提；膜污染；组合处理工艺

英文摘要： The membrane performance and efficiency can be improved by combined treatment processes. Among these processes, it is widely accepted that the control of membrane fouling and effluent water quality can be efficiently obtained by coagulation-membrane filtration. However, this combined unit process still exist some problems that need to be solved. Some part of flocs stay in the system for long time can lead to poor effluent water quality resulting from organic matter desorption from the floc, low permeation flux from compression of cake layer and the difficulty of cleaning. A new type of combined processes coagulation-air lift-ultrafiltration membrane is employed in this proposal. The mechanism of bubbles, flocs, water multiphase flow and the performance and efficiency of membrane are the key part of this proposal, the purpose is to achieve efficient operation and high water quality. By controlling bubbles velocity and concentration(batch or continous), coagulation conditions, steady or pulsate flow, transmembrane pressure ect, the processes of coagulation-air lift-ultrafiltration could be efficiently combined. A highly automated system would be build in order to test the multiphase flow mechanism and efficient operation strategy. The floc size distribution, fractral dimension, bubbles velocity and concentration,

英文关键词： Multiphase flow；Membrane performance；Air lift；Membrane fouling；Combined treatment processes