中空纤维真空膜蒸馏处理硫酸废液试验研究

Experimental study on the treatment of sulfuric acid waste by hollow fiber vacuum membrane distillation

为了解决工业硫酸废液处理过程中分离效率低、运行稳定性差的问题,设计搭建了一种基于聚四氟乙烯中空纤维的真空膜蒸馏浓缩回收系统,并开展了不同工况下蒸发浓缩硫酸溶液试验,研究了操作参数对系统产水特性的影响。结果表明:随着进料溶液硫酸质量分数和真空侧压力增加,膜通量减小;而随着进料温度和进料流量增加,膜通量增加;另外,在进料溶液硫酸质量分数2%,进料温度80℃,进料流速1.0 m/s的工况下连续运行10 d,膜通量略有减小,冷凝水电导率波动范围为11~13μS/cm,远低于自来水电导率(200μS/cm),系统的分离效率为99.9%。中空纤维真空膜蒸馏浓缩回收系统具有良好的运行稳定性,能够实现对硫酸废液的高纯分离,应用前景非常广阔。

In order to solve the problems of low separation efficiency and poor operation stability in the process of industrial sulfuric acid waste treatment,a concentration and recovery system of hollow fiber vacuum membrane distillation based on polytetrafluoroethylene(PTFE)was proposed.Experiments on concentration of sulfuric acid waste by vacuum membrane distillation under different working conditions were carried out to study the influence of operation parameters on the water production characteristic of the system.The results showed that the membrane flux decreased with the increase of feed concentration and vacuum side pressure,while increased with the increase of feed temperature and feed velocity.In addition,the system operated continuously for 10 days under the conditions of feed concentration of 2%,feed temperature of 80℃and feed velocity of 1.0 m/s,the membrane flux of the system decreased slightly,and the fluctuation range of condensed water conductivity was 11-13μS/cm,which was much lower than that of tap water(200μS/cm),and the separation efficiency was as high as 99.9%.The system had excellent operation stability and could achieve high purity separation of sulfuric acid waste,which had a broad application prospect.