Microbial dynamics and performance in a microbial electrolysis cell-anaerobic membrane bioreactor

Membrane fouling restricts the wide application of anaerobic membrane bio-reactors (AnMBRs). In this study, a microbial electrolytic cell (MEC)-AnMBR biosystem was constructed to relieve membrane fouling. Total chemical oxygen demand (COD) removal efficiency and methane production in MEC-AnMBR were increased to 6.7% and 77.1%, respectively, in comparison to AnMBR. The membrane fouling of MEC-AnMBR was greatly lessened by the slower growth of extracellular polymeric substances (EPS) and soluble microbial products (SMP). High-throughput sequencing analysis showed that Synergistaceae-uncultured and Thermovirga were enriched in MEC-AnMBR, and Thermovirga was found as the key functional microorganism. These results indicated that MEC-AnMBR could simultaneously enhance the reactor efficiency and mitigate membrane fouling.