钱塘江水经臭氧化后过超滤膜,考察臭氧对超滤膜过滤地表水中有机物的作用,进而考察其对膜过滤特性的影响。结果表明,钱塘江水中的有机物以小分子、亲水组分为主;臭氧接触时间为20.0min时,膜出水中DOC和UV254的总去除率分别达到39.3%、73.1%;随着臭氧接触时间的增加,膜出水DOC中分子量〈3ku的有机物所占比例下降,分子量〉3ku的有机物所占比例几乎不变或稍有升高,膜出水UV(254)中不同分子量有机物的比例变化与DOC相反;总体看来,投加臭氧使膜出水中强疏水组分的比例下降,弱疏水及亲水组分的比例则有增加趋势。臭氧化可有效缓解膜污染,臭氧接触时间为5.0min时膜污染下降率最大,为75.4%。
In order to investigate the effect of ozone on organic matter in surface source water during ultrafiltration and characteristic of membrane filtration,Qiantang River water oxidized by ozone was filtrated treated by UF membrane.The results showed that organic matter mostly focused on low molecular weight and hydrophilic fraction in Qiantang River water.The total rejection efficiencies of DOC and UV254 in permeate water were 39.3% and 73.1%respectively with ozonization time of 20.0min.With the increase of ozonization time,the proportion of DOC with molecular weight of smaller than 3ku was decreased,while that of molecular weight larger than 3ku changed slightly or increased in permeate water.However,UV(254) in permeate got a contrary results to DOC.The proportion of strongly hydrophobic organic matter decreased and that of weakly hydrophobic or hydrophilic organic matter increased in permeate by ozone oxidation.Ozonation could alleviate the membrane fouling effectively,membrane fouling declining rate reached the maximum value of 75.4% when ozone contact time was 5.0min.