浊度和腐植酸对超滤膜污染过程的研究

Characteristics of membrane fouling by turbid and humic substances

对超滤膜污染的两种数学模型——滤饼层过滤模型和膜孔窄化模型进行了理论分析,结合用国产中空纤维超滤膜对浊度和腐植酸混合液进行直接过滤试验的结果,证明两种模型均可描述超滤膜污染过程,并说明腐植酸是造成膜污染的主要物质,但膜孔污染主要发生在膜过滤的初期,而膜表面沉积污染发生在膜过滤的中期．

Theoretical analysis was conducted on two typical models of membrane fouling——cake filtrationmodel and pore narrowing model. The applicability of the two models on practical processes was verified by a series of experiments of direct filtration of turbid and/or humic suspensions using hollow - fiber ultrafiltration membrane. Humic substances were found to be the main pollutants attributing to membrane fouling, whereas fouling was alleviated as tubid was added to humic raw water. It is also evident that pore narrowing mainly happens in the initial period of a filtration circle,but cake filtration becomes dominant after the initial period.