Effect of different temperatures on performance and membrane fouling in high concentration PAC–MBR system treating micro-polluted surface water

► Low temperature (10°C) delayed the start-up by 9days and the complete nitrification by 10days. ► 50g/L PAC–MBR had high NH3-N removal efficiency (above 90%) at 10 and 20°C. ► 50g/L PAC–MBR got better organic matters removal (10% DOC, 5% UV254 and 4% SUVA) at 10°C. ► Carbohydrate (SMP) was the main matter causing membrane fouling at low temperature (10°C). ► There was no obvious chemical irreversible fouling, even at 10°C. A bench-scale immersed microfiltration coupled with 50g/L PAC was developed to treat micro-polluted surface water (MPSW) under 10 and 20°C and the effects of temperatures on the performance and the membrane fouling were also investigated. The low temperature (10°C) delayed the time for the start-up by 9days and the complete nitrification by 10days. In the stable operation, two systems both had high NH3-N removal efficiency (above 90%) and better removal of organic matters (10% DOC, 5% UV254 and 4% SUVA) at 10°C. Polysaccharides (SMP) were the main membrane fouling matters at low temperature (10°C) and low temperature (10°C) didn’t cause serious chemical irreversible membrane fouling.