双极膜电渗析技术处理稀土钠皂化废水回收液

采用双极膜电渗析（BMED）技术处理稀土钠皂化废水回收液，使回收液中的氯化钠转化为氢氧化钠溶液（简称碱）和盐酸（简称酸）而回用。考察了电流和初始酸碱浓度对膜对电压、回收的酸和碱的浓度、电流效率和能耗的影响。实验结果表明，随电流的增大，膜对电压升高，回收的酸和碱的浓度也明显增加，电流效率和能耗均提高;随初始酸碱浓度的增加，膜对电压、电流效率和能耗均下降，回收的酸和碱的浓度逐渐增加;综合考虑各方面因素并侧重考虑回收的酸和碱的浓度，本实验适宜的工艺条件为：电流25 A、初始酸碱浓度0.3 mol/L。在此条件下反应150 min，回收酸的浓度为1.24 mol/L，回收碱的浓度为1.55 mol/L。

Treatment of Recovered Solution from Rare Earth Sodium Saponification Wastewater by Bipolar Membrane Electrodialysis Technology

The recovered solution of rare earth sodium saponification wastewater was treated by bipolar membranes electrodialysis （BMED） technology to convert sodium chloride into sodium hydroxide （alkali） and hydrochloric acid （acid） for reuse. The effects of current and initial alkali and acid concentrations were studied. The experimental results show that：With the increasing of current density，the membrane voltage，concentrations of the recovered alkali and acid，current efficiency and energy consumption are all increased；With the increasing of initial alkali and acid concentrations，the membrane voltage，current efficiency and energy consumption are decreased but the concentrations of the recovered alkali and acid are increased gradually；In consideration of all factors and particularly the concentrations of recovered alkali and acid，the process conditions are determined as followed：current density 25 A，initial alkali and acid concentration 0.3 mol/L；When the wastewater is treated under these conditions for 150 min，the concentrations of the recovered alkali and acid are 1.24 mol/L and 1.55 mol/L respectively.