Abstract: Single-stage electrodialysis and multi-stage counter-current electrodialysis were used, respectively, to desalinate ammonium sulfate solution at the concentration of 0.52 mol/L under current-constant condition. The results showed that the phenomena of concentration diffusion and water leakage were obviously alleviated by using a multi-stage counter-current electrodialysis, while they were severe in the end period by using single-stage electrodialysis. Comparing two-stage electrodialysis and three-stage electrodialysis with single-stage one, the removal amount of salt in dilute cell was increased by 7.9% and 22.5%, the concentration of salt in concentrated cell increased by 1.6% and 6.5%, the flux increased by 7.0% and 18.5%, and the energy consumption reduced by 12.0% and 32.0%, respectively.

Key words: electrodialysis, desalination, concentration, multi-stage counter-current, concentration diffusion, water leakage, flux

摘要： 在恒流操作条件下，分别采用单级和多级电渗析对0.52 mol/L硫酸铵水溶液进行脱盐实验. 结果表明，采用多级逆流电渗析操作能明显缓解单级电渗析后期的浓差扩散和水渗漏现象. 与单级电渗析相比，两级和三级电渗析淡室中盐脱除量分别提高了7.9%和22.5%，浓室中盐浓度提高了1.6%和6.5%，膜通量提高了7.0%和18.5%，能耗分别降低12.0%和32.0%.

关键词: 电渗析, 脱盐, 浓缩, 多级逆流, 浓差扩散, 水渗漏, 膜通量