Summary: | Filtration backwashing is necessary for the effective operation of membrane modules, and intermittent aeration helps to remove nutrients, which can save energy and effectively control the occurrence of membrane contamination. In this study, membrane contamination was controlled using an MBR in intermittent aeration operation mode and a filtration backwash cycle; difficult organic matter and nitrogen (COD and NH<sub>4</sub><sup>+</sup>-N) were used as the main contamination indicators for this study; and the main membrane contamination components, extracellular polymers (EPs), and soluble microbial products (SMPs) were detected. The results show that the average removal of COD and NH<sub>4</sub><sup>+</sup>-N could reach 86.45% and 92.47%, respectively, with a 2.0 day intermittent aeration time and 9/1 min filtration backwash cycle mode, and it also helped to reduce the membrane contamination, as shown by a decrease of 11.87% in bound EPs (EPS<sub>Bound</sub>) and an increase of only 5.32% in SMPs. Microbiological analyses revealed that Proteobacteria and Acinetobacter, as dominant bacteria (50.90%), were the main causes of membrane contamination.
|