水体溶解性有机物正渗透膜污染特性及机理研究

Forward osmosis (FO) is an emerging osmotically-driven membrane separation process with the advantages of the very low hydraulic pressure required, lower energy consumption，higher rejection efficiency, low fouling tendency and higher water recovery. The application of the forward osmosis technology for the removal of aquatic dissolved organic matter (DOM) has a potential in the drinking water production by membrane processes with benefits of low energy consumption, high permeate quality and low concentrated water discharge. However, the systematical researches of fouling mechanisms of the FO membrane by DOM have not been studied yet. This research systematically investigated the fouling mechanism of FO membrane by DOM, such as factors influencing the fouling, quantitative evaluation of the fouling, morphological structure of the fouling layer, and interactions between foulants and the membrane. The effect and mechanism of organic fouling on mass transfer of the FO was explored according to the results of the flux and foulant deposition affected by the factors. Based on the studies for the quantitative methods of the flux and internal concentration polarization (ICP) of the FO membrane, this project was to quantitatively evaluate the characteristic and extent of organic fouling in FO. The characteristics of the morphological structure of the organic fouling layer on/within the FO membrane will be analyzed according to the results of the components，deposition behavior and structure of the fouling layer. The mutual adhesive force between the DOM and the FO membrane were mainly analyzed for interpretation of the mechanism of the DOM-membrane interactions. This research has very important academic value and realistic significance for the development of the theory of FO membrane and the promotion of the advanced drinking water treatment technology development.

正渗透无需外加压力、能耗低、分离率高、不易发生膜污染、回收率高，是一种新型渗透压驱动膜技术。采用正渗透技术处理水体溶解性有机物，可实现膜工艺在饮用水生产中的“低能耗、高水质、低排放”，但目前国内外尚无溶解性有机物形成正渗透膜污染机理的系统研究。本课题对溶解性有机物形成正渗透膜污染的影响因素、量化评价、污染层形态结构及污染界面相互作用等膜污染机理进行深入研究。通过对各影响因素下正渗透有机污染通量及沉积量的变化规律研究，明确有机污染对正渗透传质过程的影响规律及主要影响机理；通过对膜通量及内部浓差极化的量化方法研究，实现正渗透膜有机污染特征及程度的量化评价；通过研究污染层组分、沉积形态及结构等，明确正渗透膜有机污染层形态和结构特征；通过分析有机物及其与正渗透膜面间的粘附力等，阐释溶解性有机物-正渗透膜的相互作用机理。课题对丰富正渗透理论、促进饮用水深度处理技术发展等具有重要的学术和应用价值。

正渗透技术无需外加压力、能耗低、分离率及回收率高，是一种具有应用前景的新型饮用水深度处理技术。正渗透有机膜污染的影响因素及溶解性有机物的膜污染机理是正渗透处理饮用水水源研究的关键问题。本项目对溶解性有机物形成正渗透膜污染的影响因素、量化评价、污染层形态结构及污染界面相互作用等膜污染机理进行深入研究。正渗透膜在两种膜朝向下均可有效去除溶解性有机物；渗透曳力和化学相互作用对较小分子溶解性有机物在膜多孔支撑层内的堵塞污染起到重要作用，而减弱的内部浓差极化对正渗透膜污染具有一定的补偿作用；溶解性有机物与膜支撑层表面的相互作用（粘附作用力）对正渗透的初期污染影响较大，而有机物之间的相互作用（聚合作用力）可能控制着正渗透膜的后期污染。本研究发表研究论文2篇，其中SCI收录1篇，授权中国发明专利1项。