欢迎访问过程工程学报, 今天是

›› 2008, Vol. 8 ›› Issue (5): 887-891.

• 反应与分离 • 上一篇    下一篇

结垢对电吸附除盐的影响及其控制

赵雪娜 倪文 陈兆林   

  1. 北京科技大学金属矿山高效开采与安全教育部重点实验室 北京科技大学金属矿山高效开采与安全教育部重点实验室 北京科技大学金属矿山高效开采与安全教育部重点实验室
  • 收稿日期:2008-05-16 修回日期:2008-06-16 出版日期:2008-10-20 发布日期:2008-10-20
  • 通讯作者: 赵雪娜

Effect of Scaling on Electrosorption Desalination and Its Control

ZHAO Xue-na NI Wen CHEN Zhao-lin   

  1. State key laboratory of High-Efficient Mining and Safety of Metal Mines, Ministry of Education University of Science and Technology Beijing State key laboratory of High-Efficient Mining and Safety of Metal Mines, Ministry of Education University of Science and Technology Beijing State key laboratory of High-Efficient Mining and Safety of Metal Mines, Ministry of Education University of Science and Technology Beijing
  • Received:2008-05-16 Revised:2008-06-16 Online:2008-10-20 Published:2008-10-20
  • Contact: ZHAO Xue-na

摘要: 利用电吸附技术对含有高重碳酸盐(HCO3-)和不同浓度Ca2+的原水进行除盐处理,研究了结垢对电吸附除盐的影响. 实验分别在Ca2+浓度为40, 144和350 mg/L三种工况下进行,结果表明,当Ca2+浓度较高时,除盐率明显下降. 对离子去除率、离子脱附率和起始工作电流的变化进行了分析,认为Ca2+与HCO3-相互作用在电吸附模块内部形成碳酸钙垢体,导致电极的双电层电容量降低,从而影响电吸附的除盐效果. 利用酸化吹脱预处理将原水中HCO3-浓度控制在100 mg/L,可使碳酸钙垢体溶解,改善模块的除盐性能. 根据HCO3-积存和工作出水pH值的变化,探讨了碳酸钙在模块内部的结晶与溶解机理.

关键词: 电吸附, 结垢, 酸化吹脱, 除盐

Abstract: The effect of scaling on electrosorption desalination was studied by using electrosorption technology to desalt feed water containing different concentrations of Ca2+ and high concentration bicarbonate (HCO3-). The experiments were carried out at three Ca2+ concentrations of 40, 144 and 350 mg/L, respectively. The results show that the desalination efficiency drops remarkably at higher Ca2+ concentrations. Analysis of changes of ion removal rate, ion desorption rate and initial working current reveals that the calcium carbonate scale formed in the electrosorption module is a result of the interaction between Ca2+ and HCO3-, which causes the decrease of electrical double layer capacitance of electrode material, and therefore affects the desalination effect. Calcium carbonate can be dissolved after using acidification-stripping as pretreatment to obtain HCO3- concentration of 100 mg/L, which results in the improvement of desalination of the module. The crystallization and dissolution mechanism of calcium carbonate in the module are also discussed based on HCO3- ion residue and pH change in the working effluent.

Key words: electrosorption, scaling, acidification-stripping, desalination

中图分类号: