摘要
膜的污染和劣化始终是制约膜技术发展的瓶颈之一.在液体分离膜过程中,浓差极化是产生膜污染的主要原因,因此减小浓差极化即可减轻膜污染.本文首先介绍了浓差极化现象和模型以及传质系数的求算,并且提出一种简单的实验方法测定膜过程的浓差极化程度,然后针对不同分子量的溶质体系对影响浓差极化程度的操作条件进行定量分析,包括操作压力和原料液循环流量,最后对如何减轻液体分离膜过程由浓差极化导致的膜污染给出几点建议.
Membrane fouling and degradation always restrict the development of membrane technology. In any membrane processes of liquid separated, concentration polarization is a primary reason that results in membrane fouling. Therefore, reducing concentration polarization amounts to relieving membrane fouling. In this article, firstly the phenomenon of concentration polarization on membrane surface, the concentration polarization model and the calculation of mass transfer coefficient are introduced, anf furthermore one ordinary experimentation is provided for predicting the degree of concentration polarization on membrane surface. Then the effects of operational condition on the membrane surface＇s concentration polarization are analyzed quantitatively, including applied pressure and solution circular flow. Lastly, a little advice on how to reduce membrane fouling that is brought about by concentration polorization is given.
出处
《膜科学与技术》
CAS
CSCD
北大核心
2005年第6期64-68,79,共6页
Membrane Science and Technology
基金
国家973计划(2003CB615701)
关键词
浓差极化
膜分离
循环流量
膜污染
concentration polarization
membrane separation
circular flow
membrane fouling
