直通式浓水分段外排型电渗析分散源海水淡化研究

Study on Seawater Desalination of Dispersive Source with Electrodialysis for Straight-Through and Segmented Concentrate Discharge

为了推广电渗析在分散源海水淡化领域的应用,针对电渗析脱盐过程能耗较高的问题,设计了电渗析浓水分段外排脱盐实验。研究了不同浓水外排段数对电渗析脱盐过程效率、能耗以及水迁移的影响。结果表明,浓水分段外排实验脱盐效率大幅提升,其中四段脱盐效果最优,相对于常规的一段浓水直排脱盐方式将盐含量从35 000 mg/L脱至500 mg/L以下所需时间减少25 min、淡水室至浓水室的水渗透量降低35.4%、吨水能耗降低31.6%、效率提高约26%。浓水分段外排脱盐方式提升了脱盐效果。

In order to promote and industrialize the application of electrodialysis in the field of dispersive source seawater desalination, the experiment was designed to solve the problem of high energy consumption in the process of electrodialysis desalination process. This paper studies the effects of different discharge segments of concentrated brine on the process efficiency, energy consumption and water migration of electrodialysis desahing process. The results show that the efficiency of desalination can be greatly improved. Among them, the desalination effect of four segments is optimal, relative to the conventional way of one segment straight discharge of concentrated water. When desahing from 35 000 mg/L to 500 mg/L, the time needed can be shorten by about 25 min, the water osmotic quantity from the diluted chamber to concentrated chamber can reduce by 35.4%, the specific energy consumption in producing 1 ton of freshwater has reduced by 31.6%, and the efficiency can be enhanced by about 26%. Therefore, the desahing effect has been substantially improved by the desahing method of segmented discharge of concentrate.