磁场在自来水纳滤过程中的影响机理初探

Tentative mechanism of magnetic field effect on the tap water NF softening

针对磁场应用于自来水纳滤软化过程的初步研究表明:与同样条件下的对照实验相比,磁场的存在可以减缓纳滤膜通量衰减的速度.对膜面结垢的电镜分析发现,磁场引入纳滤膜过程可导致膜面结晶形态的改变.不加磁场的纳滤过程中,膜面上主要生成颗粒状的方解石;加磁场的纳滤过程中,膜面上针形文石的含量增高,且大多形成团簇结构.纳滤膜面上针形文石晶体含量增多的原因可能是由于水合离子在磁场中受洛仑兹力作用做旋转运动,形成诱导磁极后在膜面上以S-N的结合次序形成链状结晶.

A tentative experiment was conducted on the tap water softening with nanofiltration(NF)membrane combined with a magnet.The experimental results indicated that magnet could deter the flux decline of NF membrane,with reference to a control system operating under the same conditions.The Scan Electronic Microˉscope(SEM)analysis on the scale formed on NF membranes revealed that magnetization changed the structure of scale formed on membrane surface.Granular calcite mainly formed on membrane surface in the NF process without magnet,while in the NF process with a magnet,needle aragonite scale formed on membrane surface inˉcreased,and most of such sale was coalescent.The increment of needle aragonite crystal may be due to hydrated ions rotate under the Lorentz force and form some deduced magnetic domains,and then such deduced magnetic domains form chain crystals on membrane surface in the order of S-N.