膜蒸馏淡化处理油田高含盐废水的实验研究

采用减压膜蒸馏技术处理油田高含盐废水，研究了真空度、废水温度、流量以及废水含盐量对膜通量与截留率的影响。实验结果表明：随着膜下游真空度增加，膜通量先缓慢增大，当真空度超过某一临界值后，膜通量急剧增加；废水温度增加，膜通量增大，且真空度越高，膜通量随温度变化的曲线越陡；提高废水流量可增大膜通量；随着废水含盐量增加，膜通量减小，当废水含盐量大于220g／L时，馏出液电导率明显增加，但各次实验的截留率仍然接近100％，表明实验用聚丙烯中空纤维膜具有很好的疏水性。

Desalination of oil-field wastewater via vacuum membrane distillation

The desalination of oil-field wastewater via vacuum membrane distillation (VMD) was studied. The polypropylene hollow fiber membrane (PPHM) was used for the process. The influences of vacuum, wastewater temperature, salt concentration, flow rate of the feed on the process were investigated. Experimental results showed that with the increasing of the vacuum in the cold side, the permeation flux increased very slowly at lower vacuum, but when the vacuum was larger than a critical value, the flux increased sharply. When the feed temperature increased, the flux increased more rapidly at higher vacuum. The flux was enhanced with the increase of the flow rate,and decreased with the increase of salts concentration. It was found that the PPHM possessed perfect hydrophobicity, the salt rejections were closed to 100%.