Characterization of micro-/nanobubbles and their inhibition in membrane fouling
This study confirmed the stable existence of micro-/nanobubbles(MNBs)in water by characterizing the microscopic morphological of graphite before and after introducing MNBs using atomic force microscopy(AFM)and a microbubble monitoring system.In order to create a testing procedure for MNB inhibition of membrane fouling,this work also integrated the membrane performance testing apparatus with the micro-/nanobubbles generating device.The effects of MNBs on PVDF membranes'anti-fouling,filtration,and permeability characteristics were methodically investigated both before and after MNBs were introduced.According to the intuitive experimental results,the introduction of MNBs might effectively block the direct adherence of pollutants to the membrane,reducing the flux attenuation rate of the PVDF membrane by around 63.4％.Furthermore,scanning electron microscopy(SEM)analysis of the microstructure of the membrane surface before and after contamination indicated that MNBs effectively suppressed the formation of pollutant cake layers and the clogging of membrane pores.While boosting the membrane's anti-fouling ability,MNBs also raised the rejection rate by around 21.3％,which could be attributed to an increase in pollutant particle size generated by MNB adsorption.Finally,nanoparticle tracking analysis(NTA)was used to examine the particle concentration and size distribution before and after the addition of MNBs to various aqueous solutions.The findings revealed that the particle size of contaminants increased after the introduction of MNBs.Based on these experimental findings,this paper suggested a technique for controlling membrane fouling through mutual adsorption of MNBs and pollutant surfaces,as well as isolating the interaction between pollutants and membrane surfaces via gas bridges effect.
万方数据
维普
