Mitigated membrane fouling of anammox membrane bioreactor by microbiological immobilization

In this study, membrane fouling behavior of anammox MBR with or without carriers made by magnetic porous carbon microspheres was investigated. The results show that Trans Membrane Pressure was an order of magnitude lower after 50days due to use of carriers, which did not directly contact with membrane surface. Scanning Electron Microscope analysis indicates that abundance of anammox bacteria formed biofilm on membrane surface. Fourier transform infrared spectroscopy combined with amino acids contents analysis for membrane surface deposition show that metabolite released by anammox bacteria contains more hydrophobic groups than hydrophilic, which was considered as important reason for its abundant existence on hydrophobic membrane surface. Microbiological immobilization not only reduces biological membrane fouling, but also mitigates organic fouling including organic matter containing COO, hydrophobic groups (CH3, CH2 and CH etc), as well as inorganic deposition. Our finding provides an effective method for mitigating MBR membrane fouling in anammox process.