双极膜电渗析技术在工业高含盐废水中的应用

摘要

双极膜电渗析(BMED)作为新型膜分离技术,可将盐转变为相应的酸和碱,围绕 BMED 技术在工业高含盐废水领域的应用已逐渐成为热点,但在实际应用中还存在一些亟需解决的难点.本文主要介绍了近年来BMED技术在处理工业高含盐废水领域的研究现状,提出和探讨了限制BMED技术在该领域大规模工业化应用的 3 个关键性问题,即与酸碱浓度和纯度有关的技术问题、与过程成本有关的技术经济性问题以及与投资成本有关的经济性问题.针对这3个问题,指出BMED技术未来发展方向应致力于降低双极膜成本,减弱或消除离子交换膜同离子泄漏及水迁移过程.对于现阶段而言,将制备的酸碱回用于系统内部,是解决酸碱品质较低而未能商品化的主要途径,同时该过程可节省酸碱外购费用,弥补BMED技术投资成本过高问题.%Bipolar membrane electrodialysis(BMED)as an advanced separation tool can effectively generate acid and base from its corresponding salts, respectively. Currently, the application of BMED for valorization of industrial high-salinity brine becomes a hot topic due to its technological superiority. However, some difficulties restrict its real practical application. In this paper, we comprehensively reviewed the application status of BMED for industrial high-salinity brine valorization in recent years and systematically discussed three critical barriers including the technical barrier associated to acid-base concentration and purity, techno-economic barrier related to process cost and economic barrier for investment cost, which hindered the large-scale industrial application of BMED technology. In view of these barriers, the further research and development of BMED technology is suggested which should focus on the reduction of bipolar membrane cost and elimination of co-ion leakage and water migration through ion exchange membrane. Presently, the reuse of prepared acid and base solution in the system process is strong recommended due to low acid-base quality as commercial product. Furthermore, this reuse process can decrease the expense of acid-base outsourcing so as to create extra economic benefit to offset the high investment cost of BMED technology.