本文利用电渗析技术对山东魏桥某电厂脱硫废水进行处理，分别对脱硫废水进行一级一段以及多级电渗析和多段电渗析浓缩规律进行研究，测定了其极限电流，考察了膜对电压和膜面流速对电渗析浓缩过程中Cl-浓度、SO42-浓度、电流、能耗、浓缩倍率以及电流效率的影响。结果表明：膜对电压对电渗析浓缩过程影响显著，随着膜对电压的增大，电流和能耗增大，当膜对电压达到1 V时，电流效率均能达到70%以上；膜面流速对电渗析浓缩过程影响不明显，当膜面流速为2.05 cm/s时，离子迁移速率达到最高，确定最佳膜对电压为1 V，最佳膜面流速为2.05 cm/s。七段电渗析和四级电渗析浓缩均能得到含盐量15%的浓缩液，其中，Cl-浓度为50 g/L，SO42-浓度为40 g/L，但四级电渗析能耗相对较高，为150 kW·h/m3，且有强烈的水迁移现象，倒换电极法能有效降低膜污染。

In this paper, the electrodialysis technology is used to treat the desulfurization wastewater of a power plant in Weiqiao, Shandong Province. The first-stage electrodialysis, the multi-step electrodialysis and the multi-stage electrodialysis were studied respectively. The limiting current was measured. The factors of concentration of Cl-, SO42-, current, current efficiency, relative concentration ratio and energy consumption on electrodialysis were studied. The results showed that the effect of the cell-pair voltage on the concentration of electrodialysis is significant. With the increase of the voltage per cell pair, the current and energy consumption increase. When the cell-pair voltage reaches 1 V, the current efficiency can reach more than 70 %. The flow rate has little effect on the concentration of electrodialysis. When the flow rate reaches 2.05 cm/s, the ion migration rate reaches the highest. The seven-step and four-stage electrodialysis can achieve an electrodialysis concentration effect with a salt content of 15%. At this time, the concentration of Cl- was 50 g/L, and the concentration of SO42- was 40 g/L. However, the four-stage electrodialysis was relatively simple, and the energy consumption was high(150 kW·h/m3), and the water migration phenomenon was obvious. Seven-step electrodialysis can produce more fresh water. However, the energy consumption of complicated process was low(140 kW·h/m3). Therefore, energy consumption can be reduced by multi-stage electrodialysis. The membrane pollution can be reduced effectively by reverse electrodialysis.

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