YU Hui,ZHANG Meng,SONG Jie,et al.Effects of Biological Fouling on Microstructure and Macroscopic Properties of Reverse Osmosis Membrane[J].China Water & Wastewater,2021,37(11 11):46-51.
Effects of Biological Fouling on Microstructure and Macroscopic Properties of Reverse Osmosis Membrane
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第37卷
Number:
11 11
Page:
46-51
Column:
Date of publication:
2021-06-01
- Keywords:
- reverse osmosis membrane; biological fouling; micro-morphology; permeability; desalination rate; water yield
- Abstract:
- As the problem of biological fouling of reverse osmosis (RO) membrane becomes more and more serious, the development and application of anti-biological fouling membrane become the focus of attention. At present, evaluation methods of membrane antibacterial property are static evaluating the antibacterial properties of membrane surface, while the dynamic test method is closer to the actual conditions of membrane operation. The characterization of the microstructure of a reverse osmosis membrane before and after fouling can further understand the membrane fouling mechanism of biological fouling. Using E. coli as a biological fouling model, the attenuation of membrane permeability and variations in microstructure caused by biological fouling were explored by dynamic experiments. The biofilm formed on the surface of the reverse osmosis membrane led to a rapid decrease of membrane water flux by more than 50%. Scanning electron microscopy (SEM) showed that the membrane surface was completely covered by biofilm. Fluorescence microscope showed that there were both live and dead bacteria in the biofilm. Biological fouling of the membrane resulted in decrease of hydrophilicity and increase of potential and roughness of the membrane surface. A new absorption peak at 1 734.68 cm-1 detected by infrared spectra indicated that proteins and esters existed on the surface of the RO membrane. Biofilm covered the separation layer, which thus affected the membrane surface performance and permeability. Biological fouling is a type of fouling which has a great impact on overall performances of membrane, so it is particularly important to prevent biological fouling.
Last Update:
2021-06-01