纳滤膜脱盐及其在海水软化中的应用

采用卷式纳滤膜进行了MgSO4、K2SO4、MgCl2等5种物质的脱盐性能研究,考察了进料操作压力和浓度对表现截留率和膜通量的影响,在此基础上研究了操作压力对海水脱盐性能的影响.实验表明,纳滤膜性能稳定,能除去海水中90％以上的SO42-以及50％以上的Mg2+和Ca2+,大幅度降低了海水的硬度,可解决传统上海水淡化过程中易结垢离子对膜的污染问题；纳滤膜软化海水可以降低海水淡化后期处理的成本和能耗；采用纳滤膜软化海水在技术上是可行的.

Desalination of Nanofiltration Membranes and its Application in Seawater Softening

Desalination experiments of five inorganic salt solutions(MgSO4,K2SO4,MgCl2,etc)have been carried out by spiral-wound nanofiltration membrane.The effects of the species and the concentration of salt as well as the operation pressure on the the apparent rejection and the flux of penetrating fluid.Studies on desalination performance of artificial seawater are also introduced.Results from the studies of desalination show that nanofiltration membrane is stable during the experiment.For SO42-in seawater nanofiltration membrane could achieved salt rejection up to 90%,and Mg2+,Ca2+ up to 50%,It could solve the problems of nanofiltration membranes pollution that existed on the traditional desalination process.Compared with distillation,nanofiltration reduce the cost of seawater desalination and energy consumption.Therefore,nanofiltration technology could be used to pretreat seawater.