Organic fouling of membrane distillation for shale gas fracturing flowback water desalination: a special interest in the feed properties by pretreatment

摘要: Shale gas fracturing flowback water (SGFFW) contains a high concentration of colloids and organics which can cause severe flux decline for membrane distillation (MD). It is desirable to identify the key foulants MD fouling/wetting real SGFFW treatment. In this study, coagulation filtrations with different molecular weight cut-off (MWCO) were applied try separate fractions pollutants evaluate their contributions decline. The 20 kDa, also belonged humic acid-like components, protein-like components fulvic removed by could effectively mitigate fouling. However, rest kDa low (i.e., 200 Da) UF membrane, had less significant effect on MD. Despite further removal small compounds Ca2+/Mg2+ NF, negligible change be observed, indicating that aromatic protein (21.2%) still wetting membrane. addition, SEM-EDS demonstrated combination organic fouling crystallization Ca Ba contributed These studies Da might vital alleviation or wetting.