水处理中膜-污染层分形界面效应与PVDF/丝瓜络亲水化分形膜抗污性能研究

Based on the fractal interface effect analysis between membrane and fouling layer in the process of water and wastewater treatment, membrane hydrophilicity and fractal structure design will be investigated to improve membrane antifouling property through experiments and theoretical analysis. By introducing the fractal dimension theory to describe the microstructure and morphology of membrane surface and sublayer, the relationship between the membrane microstructure fractal dimensions and the conventional structure parameters as well as the membrane separation performance will be verified. On the basis of this, characterization of membrane fouling by the foulant with different structures and properties will be discussed to reveal the effect of fractal interface between membrane and the fouling layer. Furthermore, the membrane microstructure fractal dimension permeability model will be derivated to clarify the dependence of membrane antifouling performance on the character of membrane microstructure fractal dimensions. Eventually, the fabrication of PVDF/luffa fiber hydrophilic UF membrane with fractal microstructure will be screened out as well as the antifouling performance will be conducted accordingly. The results would provide a new idea to solve the membrane fouling problem, and thus provide some theoretical and practical significance in the area of membrane modification, fouling assessment and specific membrane cleaning program.

基于水处理过程中膜-污染层分形界面效应的研究，开展膜亲水化和分形结构设计两方面的试验和理论研究，从而提高膜抗污染性能。引入分形理论，明确膜表层及亚层微形貌结构定量表征的方法，探明分形维数与宏观膜结构参数及膜性能的关系；探讨不同结构和性质的模型物质对不同物化特性膜的污染特征，揭示膜-污染层之间的分形界面规律；建立膜分形结构渗透模型评价膜污染机制，阐明膜分形结构设计与抗污染性能之间的关联特征；优化PVDF/丝瓜络亲水化分形膜的制备条件，探明成膜机理和实际水样的抗污染性能。项目研究成果将为解决膜污染问题提供新思路，对膜的改性和使用过程中性能的评价、针对性清洗对策具有重要的理论价值与实用意义。

本项目通过开展膜亲水化和形貌结构设计两方面试验及理论研究，从而提高膜抗污染性能。引入分形理论，明确了膜表层及亚层微形貌结构定量表征的方法，建立了膜分形结构渗透模型；探讨了不同结构和性质的模型物质对不同物化特性膜的污染特征，应用XDLVO 理论定量解析了水处理中模型污染物海藻酸钠、牛血清蛋白、腐殖酸与不同MWCO超滤膜污染中界面微距作用力，对膜污染现象及膜污染机理进行了分析，揭示了膜-污染层之间的界面污染规律；探明了丝瓜络纤维的最佳溶解方法，优化了PVDF/丝瓜络亲水化分形膜的制备条件，分析了制膜条件对膜微形貌结构的控制方法，探明了膜表层结构与亚层结构的对应规律及成膜机理；揭示了对实际水样的抗污染性能，筛选了抗污染性能优异的膜微形貌结构。项目研究成果为解决膜污染问题提供了新思路，对膜的改性和使用过程中性能的评价具有重要的理论价值与实用意义。