Abstract:

The principle of water softening by electrodeionization was expounded,and the hardness remove of tap water bythe UF/EDI technologywas studied.Although fromcharacteristic curves ofthe EDI it was indicated that the process condition is similar to that of the traditional electrodialysis,the separation efficiency of the process is greatlyenhanced.With the feed UF water of 627 μS/cm,the whole rejection of 65% of the salt ions was achieved,and the rejection of Ca²⁺and Mg²⁺are 99.7% and 99.97% respectively,the hardnessofthe product water islower than 0.05 mg/L.The EDI process is hopeful tobe a newmembrane process for water softeningwith high efficiency.

Key words: electrodeionization, packed-bedelectrodialysis, water softening

摘要：

阐述了电去离子水软化技术的原理，并对超滤/电去离子(UF/EDI)工艺用于常规自来水脱硬，制备常低压工业锅炉软化水进行了实验研究。EDI水软化过程的特征曲线表明，该过程工况与传统电渗析过程相似，但分离效率显著提高。对于电导率627μS/cm的UF原水，实验条件下EDI软化过程的总脱盐率达到65%，而Ca₂₊、Mg₂₊的去除率则分别达到99.7%和99.97%，产品水硬度>0.05mg/L。研究表明，EDI工艺有望发展成为继纳滤之后的又一高效膜软化水新技术。

关键词: 电去离子, 填充床电渗析, 水软化

CLC Number: 

• TQ085+.411