基于光谱响应的饮用水处理膜污染形成机制研究

Membrane fouling remains a significant challenge for wider application of ultrafiltration (UF) membranes; and thus it limits the competitiveness and subsequent acceptance of UF membrane water treatment processes. A key to breakthroughs in understanding of fouling phenomena is the development of novel, non-invasive, in situ quantification of physical-chemical processes occurring during membrane filtration. The focus of this proposal is to investigate the evolution and mechanism of membrane fouling utilizing a novel and comprehensive spectroscopic analytical method on the basis of spectroscopy, chemometrics and thermodynamics. The main aspects of the proposal include: the establishment of mechanistic correlation between the optical absorption features and the organic foulants; the design of an integrated, online monitoring technique that provides dynamic and real-time information of fouling phenomena; a study on quantitative and qualitative analysis of species composition of fouling organisms based on the dynamics of optical response of foulants; the development of a dynamic model from a mesoscopic perspective to reveal interactions between different foulants and a systematic analysis of the flow field characteristics in membrane filtration processes. We anticipate that the research outlined in this proposal will have an impact on fundamental understanding of membrane fouling--highlighting mechanisms, dynamics of interfacial adsorption of foulants and clarifying the ‘competitive adsorption’ involved in membrane fouling phenomena--and will prove to be a disruptive technology to provide theoretical support for effective control of membrane fouling.

膜污染是制约膜分离技术在水处理中应用的瓶颈问题，科学认识膜污染形成机制是实现膜污染控制的有效途径，开发科学适用的膜污染在线监测技术是有效破解膜污染问题的关键。本项目着眼于科学监测分析膜污染形成过程和作用机制这一难题，立足于红外光谱对大多数有机物官能团均有较好的特征吸收光谱特性，采用红外光谱技术与膜分离技术的有机结合，借助光谱学、化学计量学和热力学的理论和分析方法，开发建立基于光谱响应的膜污染原位监测方法，探索研究光谱特征与强致膜污染中典型污染物的“指纹”谱关系，建立利用光谱特征参数确定典型污染物的定性和定量方法，从介观理论的角度研究污染物界面性质及相互作用机制，阐明深刻影响膜污染行为的“竞争吸附”现象，破解复合污染条件下污染物的沉积进程诱因，分析膜过滤流场热力学与动力学特征对膜污染发展的影响机制，为有效控制膜污染提供理论支撑。

膜法水处理过程中膜污染构成了制约膜技术发展和应用的瓶颈，准确解析膜污染形成机制是实现膜污染控制的有效途径，开发科学适用的膜污染在线监测技术是有效破解膜污染问题的关键。本项目以强化污染物的光物理响应效应提升膜法水处理过程膜界面原位探测能力为目标，膜界面光场调控为核心，提出激光腔光场调控提升光脉冲稳定性和波长调谐性作用机制，构建了满足水处理过程膜污染原位在线监测需求的高稳定性、波长宽波段连续可调光源系统，解决了现有光源系统性能与水处理功能需求不匹配的技术难题；创新融合光纤感知、环境光谱、光片显微成像和膜过滤技术，提出了水环境下光场调控强化污染物光响应特征作用机制，阐明了水处理过程膜污染高灵敏原位光学感知机理，构建了“膜-水”界面污染物高灵敏原位感知和膜污染形成过程时空分辨原位可视化监测平台，实现膜污染形成机制解析方法的重要突破。基于建立的膜法水处理过程非侵入式动态感知平台探明了污染层化学构成的量化识别关系，监测了饮用水处理过程中不同污染物在膜表面和内部的吸附、沉积、积累动态过程，解析了全膜尺度污染物构成和三维物理形貌的时序发展进程，揭示了膜污染时空分布、膜污染行为与界面相互作用的关联机制，立体解析了膜污染形成过程和作用机制，为有效控制膜污染提供了理论和技术支撑。研究成果在Water Research、Journal of Membrane Science等国际SCI收录期刊共发表论文20篇（其中中科院一区论文7篇、JCR Q1区18篇），1篇入选ESI高被引论文，1篇入选Photonics Research Most Cited Articles，1篇入选Journal of Materials Chemistry C Hot Papers，光纤微结构光场调控强化光-物质相互作用实现探测增敏的研究成果被Advanced Optical Materials以第一作者邀请撰写综述论文，并被编辑推荐为正封面论文；申请国家发明专利3项；已培养2名博士和4名硕士毕业生。