减压膜蒸馏浓缩硫酸钠溶液的实验研究

Concentration of sodium sulfate from its aqueous solution by vacuum membrane distillation

采用减压膜蒸馏技术在较低真空度下浓缩Na2 SO4 水溶液 ,研究了真空度、料液温度、料液流速以及料液浓度对膜通量与截留率的影响。结果表明 ,随着膜下游真空度增加 ,膜通量增大 ;料液温度显著影响膜通量 ;随着料液浓度增加 ,膜通量严重衰减 ;实验条件下聚丙烯中空纤维膜表现出很好的疏水性 ,Na2 SO4 的截留率接近10 0 %。

The experimental study on concentration of sodium sulfate from its aqueous solution by vacuum membrane distillation(VMD)at lower vacuum degree was carried out.The influences of vacuum degree,temperature,concentration and flow rate of the liquid feed on the process were investigated.Experimental results had showed that with the increase of the degree of vacuum of the cold side,the permeation flux increased.When the temperature increased,the flux increased sharply.The flux was enhanced with the increase of the flow rate.But when the concentration of sodium sulfate increased,the flux decreased.It was found that the polypropylene hollow fiber membrane possessed perfect hydrophobic property,the separation efficiency was closed to 100%.