浓盐水超声减压膜蒸馏参数优化及污染控制实验研究

EXPERIMENTAL STUDY OF PARAMETER OPTIMIZATION AND POLLUTION CONTROL IN ULTRASOUND VACUUM MEMBRANE DISTILLATION FOR BRINE

采用聚丙烯(PP)和聚四氟乙烯(PTFE)中空纤维疏水膜材料制成的膜组件,对浓盐水超声减压膜蒸馏过程进行研究。以膜蒸馏通量为评价参数,研究了温度、真空度、流速、超声频率和超声功率5个影响因子,实验表明膜蒸馏通量随温度和真空度的增大而增大;膜蒸馏通量随流速和超声频率的增加而增大,但增加到一定值后膜蒸馏通量随着流速和超声频率的增大趋势减弱。膜污染的主要成分以Ca CO3和Na Cl为主,采用5%的盐酸溶液对膜的外层清洗30 min,然后用蒸馏水冲洗30 min可使膜通量恢复到95%。研究表明超声减压膜蒸馏,不仅能提高膜蒸馏通量,还能提高出水水质。

Using the hollow fiber hydrophobic membrane from polypropylene( PP) membrane material and polytetrafluoroethylene( PTFE) membrane material,the paper studied on ultrasonic vacuum membrane distillation process for concentrated brine. With membrane distillation flux as evaluation parameters,the five influence factors of temperature,vacuum,flow velocity,ultrasonic frequency and ultrasonic power were studied. Experiments showed that membrane distillation flux increased with temperature and the degree of vacuum; the membrane distillation flux in creased with the increase of the flow rate and ultrasonic frequency,but to a certain value that the trend of membrane distillation flux would weaken with increasing flow rate and ultrasonic frequency. The main component of membrane pollution was Ca CO3 and Na Cl,using 5% hydrochloric acid solution cleaning the outer membrane for 30 min,then distilled water for 30 min,the membrane flux can be restored to 95%. Experiment results demonstrated the ultrasonic vacuum membrane distillation system can improve membrane flux and water quality.