硅橡胶膜渗透蒸发去除水中VOC性能的研究

Study on the removal capacity of VOC from water by pervaporation process through a silicone rubber membrane

研究了硅橡胶膜渗透蒸发去除水中挥发性有机化合物(VOC)的性能。考察了水的进料流量、温度、进料液中溶解气体和水蒸气的存在对VOC去除率的影响。结果表明,溶液中VOC气体的进料质量分数为2.0×10-4、进料流量为70cm3/min时,苯的去除率达到了90%,而进料流量为50cm3/min时,甲苯的去除率仅达72%,且随进料温度的增加而增加。空气溶解气体的存在增加了膜去除效率,但水蒸气的存在降低了VOC气体的透过系数。基于Henry系数的计算模型对实验结果进行了较好的预测。

The removal capacity of VOC from water by pervaporation process through a silicone rubber membrane has been studied. The effects of water feeding volumn, feeding temperature, the existence of dissolved gas and water vapor in feeding liquid on the removal efficiency of VOC are investigated. The experimental results show that the re-moval efficiency of benzene could reach 90%, when the feeding concentration of VOC gas in the solution is 2.0×10^-4, and feeding volumn of flow is 70 cm^3/min. But the removal efficiency of toluene is only 72% when feeding volumn of flow is 50 cm^3/min. And, the removal efficiency of VOC increases with the increases of feeding temperature. The existence of dissolved gas enhances the removal efficiency of the membrane, but the existence of water vapor decreases the permeation coefficient of VOC gas. Based on the calculation model of Henry coefficient, a pretty good prediction on the experimental results has been carried through.