果实类中药水提液在反渗透过程中的临界渗透压及膜污染状况

Critical Osmosis Pressure of Decotions of Fructification Herbs in Reverse Osmosis Process and the Situation of Membrane Fouling

将临界渗透压(COP)引入果实类中药水提液反渗透过程的研究。以蒺藜、牛蒡子、山楂的水提液为研究对象,分析了渗透压与膜通量衰减率的关系。结果表明,反渗透过程中膜通量衰减率与渗透压呈正相关;不同体系的COP不同。选择药液渗透压小于、等于及高于COP的试验点,绘制反渗透过程中的阻力分布图。结果显示,浓差极化现象是造成膜污染的主要原因。根据4种堵塞模型的拟合结果,3种水提液的反渗透过程中膜污染特性均符合完全堵塞模型。

The application of critical osmosis pressure （COP） to the research of decotions of fructification herbs in reverse osmosis process was investigated, The relationship between the decline rate of flux and osmosis pressure of decotion was analyzed with the decofions of Tribulus terrestris L., Arctium lappa L. and Crataegus pinnatifida Bge.. The results showed that there was a positive correlation between the above two factors and the value of COP was changed according to the kinds of the herbal decotion. The contributions of membrane resistance at the point at which the osmotic pressure of the decotion was lower than, equal to or higher than COP were drawn. The results showed that the concentra- tion polarization was the main cause of membrane fouling. Based on the filling results of four different blocking models, the characteristics of membrane fouling in the reverse osmosis process of the three decotions were all consistent with the complete blocking model.