Reclaimed water is a critical source of water in Singapore and globally. Common practical limit of existing technology based on microfiltration/ultrafiltration-membrane bioreactor (MF/UF-MBR) and reverse osmosis (RO) for water reclamation has 75-85% recovery due to RO membrane fouling.This technology presents a hybrid system consisting of a high retention nanofiltration-membrane bioreactor (NF-MBR) and RO developed to achieve ≥90% of water recovery. NF-MBR produces superior quality effluent because the NF membrane can retain low molecular weight organics and scale forming divalent ions. Thus, membrane fouling in downstream RO process can be alleviated significantly, which allows higher recovery.
This technology could be applied in the following areas for significant improvement of micropollutant removal, especially recalcitrant trace organics: Wastewater reclamation Industrial water recycling
This hybrid system with lower fouling potential of RO feed water offers the following advantages: High recovery water reclamation Lower chemical use, less energy consumption associated with RO membrane fouling Longer RO membrane lifespan Less sludge production Reduced water production cost