藻类有机物对纳滤膜去除萘普生效果影响研究

研究了2种藻类(鱼腥藻/小环藻)有机物(AOM)对纳滤膜去除萘普生(NPX)的影响效果.结果表明,在藻类AOM存在的情况下HL纳滤膜对NPX的去除率由63%增加至64.7%(小环藻)和72.7%(鱼腥藻);但同时造成了严重的膜污染,比通量由99.7%下降至89.6%(小环藻)和86.3%(鱼腥藻).研究发现,藻类AOM的中等分子量(1.5~5kDa)发挥了重要的作用,它们主要由疏水性有机物构成,紧密地黏附在膜表面形成滤饼层,使膜表面的疏水性增强.滤饼层的疏水性造成膜通量衰减并提高NPX去除率.研究还表明,鱼腥藻AOM在中等分子的疏水性明显比小环藻的强,造成的膜污染更严重以及更高的NPX去除效果.

Effects of algogenic organic matter on naproxen removal by NF membrane

Eeffects of two kinds algae (Anabaena, Cyclotella) AOM on naproxen (NPX) removal by HL nanofiltration membrane were investigated. In the presence of AOM, NPX removal by NF increased from 63% with only NPX to 64.7% with Cyclotella and 72.7% with Anabaena, and severe fouling occurred with flux decreasing from 99.7% with only NPX to 89.6% with Cyclotella and 86.3% with Anabaena. It was found that medium molecular weight (MW) 1.5~5kDa with two AOM play a significant role in enhancing NPX removal and resulting fouling.They composed mainly of hydrophobic organics, and could adhere closely to NF membrane, forming cake layeron the surface of NF membrane, thus enhanced hydrophobicity of membrane. The hydrophobicity of cake layer was responsible for flux decline and increased NPX removal. The experiment exhibited also that AOM of Anabaena containedmore hydrophobity in 1.5~5.0k Da of MW than that of Cyclotella, thus resulted more severe fouling and higher NPX removal.