Abstract: Re-desalting of concentrated seawater produced from seawater desalination process can further improve the recovery rate of freshwater and avoid wasting the high quality mineral resources and eliminate pollution to the marine environment. This paper reviewed the following techniques particularly：multi-effect distillation，eutectic freezing crystallization，electrodialysis，membrane distillation and membrane distillation-crystallization. The principle，applications，advantages and shortcomings of these techniques were analyzed. The development of comprehensive utilization and “zero liquid discharge” of concentrated seawater based on diverse hot-film integration process were discussed. Except for the relatively mature multi-effect distillation and electrodialysis，most of other techniques are still in the laboratory stage. This paper indicated that membrane distillation driven by renewable energy coupled with reverse osmosis developing efficient salt chemical industry would be one of the most promising methods of concentrated seawater desalination.

Key words: concentrated seawater, desalination, zero liquid discharge

摘要： 对海水淡化过程产生的浓海水进行再脱盐，可进一步提高淡水回收率，并有效避免优质化学资源的浪费和对海洋生态环境的污染。本文介绍了多效蒸馏、共晶冷冻结晶、电渗析、膜蒸馏、膜结晶等浓海水再脱盐技术的原理、特点、应用实例和新进展，并对比分析了各种技术的优势和存在的不足，对基于多种热膜集成过程的浓海水“零排放”和综合利用技术进展作了重点讨论。最后指出，除相对成熟的多效蒸馏法和电渗析法外，其他多数浓海水再脱盐技术仍处于实验研究阶段，将反渗透与可再生能源驱动的膜蒸馏技术进行耦合发展高效盐化工将是浓海水处理领域的重要方向。

关键词: 浓海水, 脱盐, 零排放