| A method for obtaining the real retention of nanofiltration membrane |
| Authors： Zhang Xianqiu ,Du Mingxia,Wang Zhiliang, Zhang Yong，Jia Guozheng |
| Units： 1, School of Environment Science & Engineering, Nanjing Normal Universty Nanjing 210042, China) |
| KeyWords： nanofiltration membrane; real retention; concentration polarization |
| ClassificationCode：TQ028.8 |
| year,volume(issue):pagination： 2010,30(6):0-0 |
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Abstract： |
| Abstract: The real retention of membrane is usually used when performances of nanofiltration membrane are characterized . But the real retention is only obtained from mass transfer coefficient at present because it can not be directly measured. It is difficult for correctly calculation the real retention of spiral-wound modules because there are large difference among mass transfer coefficient equations published in literatures. In this paper, based on concentration polarization theoretic model and the flow structure of spiral-wound modules，and combined permeation experiments results with NF90-2540 spiral-wound modules, a equation for calculation the real retention of nanofiltration membrane was established. Meanwhile, the experimental and calculation results showed concentration polarization was mainly controlled by permeation flux and solution velocity in membrane: concentration polarization notably increased at low velocity, and the difference between observed retention and real retention was notable; concentration polarization notably lowered as velocity increasing, and when velocity was higher than 0.2m/s, the difference between observed retention and real retention was small. |
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Funds： |
| 江苏省环保厅基金资助项目(200802)；江苏省环境工程重点实验室开放课题（KF2009006） |
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AuthorIntro： |
| 张显球（1971—），男，安徽太湖人，博士，副教授，从事水污染控制与膜分离技术研究。 |
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Reference： |
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