Sub-critical filtration conditions of commercial hollow-fibre membranes in a submerged anaerobic MBR (HF-SAnMBR) system: The effect of gas sparging intensity

► A SAnMBR demonstration plant was operated with urban wastewater at high MLTS. ► A modified flux-step method was conducted under different gas sparging intensities. ► The JC ranged from 12 to 19 LMH for SGDm values between 0.17 and 0.5 Nm3 h−1 m−2. ► A stable operation of the membranes was observed at fluxes close to the obtained JC. ► No irreversible fouling problems were detected, even for high MLTS concentrations.