中文摘要：

目的研究中药水提液真空膜蒸馏过程中的膜通量衰减和清洗方法。方法选择代表性中药（黄芩、白芍、二丁颗粒）水提液,通过恒浓、浓缩实验分析膜通量衰减。以通量恢复率和膜表面结构变化为指标,考察不同清洗方法对聚偏氟乙烯疏水膜的效果。结果与吸附污染相比,浓度变化对膜通量的影响更大。酸碱液结合的清洗效果最好,通量恢复率可达97.98%;超声波清洗会破坏膜的表面结构,使通量恢复率大于100%。结论酸碱液（0.3%氢氧化钠＋0.3%柠檬酸）结合更适合用于清洗聚偏氟乙烯疏水膜。

英文摘要：

AIM To study the membrane flux attenuation and cleaning methods during vacuum membrane dis- tillation for Chinese herbs water extraction. METHODS During the water extraction of Chinese herbs （Scutellaria baicalensis Georgi, Paeonia lactiflora Pall. ） and formulated medicine （Erding Granules）, the membrane flux at- tenuation was analyzed by constant concentration and concentration experiments. As revealed by the indices of re- covery rate of flux and change of membrane surface structure, the effects of different cleaning methods on polyvinyl- idene fluoride hydrophobic membrane were investigated. RESULTS Compared with fouling adsorption, concen- tration changes contributed more on membrane flux. The combination of acid and alkali solutions were found to have the best cleaning effect with a flux recovery rate of 97.98% , while ultrasonic cleaning damaging the membrane sur- face structure had a flux recovery rate of more than 100%. CONCLUSION The combination of acid and alkali solutions （0.3% sodium hydrate ＋ 0.3% citric acid） takes priority in cleaning polyvinylidene fluoride hydrophobic membrane.