Integrated Fixed Film Activated Sludge (IFAS) membrane BioReactor: The influence of the operational parameters.

• A short-term analysis of a IFAS-MBR system was carried out over a two-year survey. • The system performance was mostly affected by the influent C/N ratio variation. • Biofilm on the carriers was able to sustain nitrification even at low SRTs. • A kinetic specialization of the two biomasses was highlighted by respirometry. • Possible to operate the system at low mixed liquor SRTs enhancing PAO activity. The present paper investigated an Integrated Fixed Film Activated Sludge (IFAS) Membrane BioReactor (MBR) system monitored for 340 days. In particular, the short-term effects of some operational parameters variation was evaluated. Results showed a decrease of the removal rates under low C/N values. Respirometry results highlighted that activated sludge was more active in the organic carbon removal. Conversely, biofilm has a key role during nitrification. The major fouling mechanism was represented by the cake deposition (irreversible). [ABSTRACT FROM AUTHOR]