Study on Treatment of Saline Wastewater by DC Corona Discharge in Cooperation with Membrane Distillation
Membrane distillation technology is particularly suitable for the treatment of treating high salinity waters due to independent of energy requirement from salinity.However,the low membrane flux is the technical bottleneck that limits its wide application.In this paper,the influence of corona discharge on membrane distillation process of polyvinylidene fluoride(PVDF)hydrophobic membrane is studied by means of corona discharge coupled with mem-brane distillation under different electrode structures,voltage polarity and discharge intensity.It is found by experi-ment that the membrane flux promotion effect is related to the electrode structure and the polarity effect is existed.In case of single and multiple needle corona discharge,the membrane flux can be increased from 0.108 g/(cm2·h)to 0.146 g/(cm2·h).After the stop of the corona discharge the membrane flux is recovered to is initial level.The study in this paper shows that the combination of corona discharge and membrane distillation can improve membrane flux and that the corona discharge does not damage PVDF hydrophobic membranes.During corona-assisted membrane distil-lation,the directional electrophoresis of charged droplets above the film plays a certain degree of inhibition on the membrane flux,while the formation and development of ionic wind play a facilitating role.
万方数据
维普
