In order to find out the technological characteristics of the treatment of high-salinity wastewater by vacuum membrane distillation (VMD) process, a lab-scale VMD setup was used to investigate the treatment effect of stimulated high-salinity wastewater. The effect of operational parameters, including vacuum degree (0. 10 ～0. 98 atm, 1 atm = 101 325 Pa), temperature (30 ～ 70 ℃), feed flow rate (10. 5 ～ 41. 8 L/h) and feed flow salt concentration (30 ～ 200 g/L), on the membrane flux was examined. The results showed that the maximum permeate flux could reach 4. 21 L/ (m2·h) under the most optimized conditions (i. e., vacuum degree was 0. 98 atm, temperature was 70 ℃, feed flow rate was 41. 8 L/h, and feed flow salt concentration was 35 g/L). The analysis result of multiple linear regression indicated that vacuum degree has the most obvious influence on permeate flux, followed by temperature, feed flow rate and salt concentration. In addition, the salt concentration of permeated water was less than 10 μg/L for all experiments in this study, and that meant the permeated water could be reused or discharged directly. It is concluded that VMD process is a promising method for treating high salinity wastewater.%为研究真空膜蒸馏(vacuum membrane distillation,VMD)技术对高盐废水处理的工艺特性,采用VMD小试装置研究了模拟高含盐废水处理效果,分析了真空度(0. 10～0. 98 atm,1 atm=101 325 Pa)、温度(30～70℃)、进水流速(10. 5～41. 8 L/h)和含盐量(30～200 g/L)等条件对膜通量的影响.实验结果表明:当真空度为0. 98 atm、温度为70℃、进水流速为41. 8 L/h、含盐量为35 g/L时,膜通量可达到最大值4. 21 L/(m2·h).多元线性回归拟合结果表明,真空度的改变对膜通量的影响最大,其次为温度,进水流速和含盐量影响较小.另外,真空膜蒸馏工艺的冷凝水含盐量低于10μg/L,能够达到回用或外排标准.可见真空膜蒸馏工艺是一种很有前途的高含盐废水处理技术.
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