Sustainable treatment of dairy industry wastewater using an integrated anaerobic membrane bioreactor-reverse osmosis system for industrial water reuse

The increasing demand for water in industrial processes has prompted the exploration of sustainable water management technologies. This study investigated the integration of an anaerobic membrane bioreactor (AnMBR) with reverse osmosis (RO) for energy recovery and water reuse in the dairy industry. The AnMBR system, fed with dairy industry wastewater, was operated under mesophilic conditions, and its treatment and filtration performances were evaluated. The permeate from the AnMBR system was subsequently treated by the RO system, and the quality of reclaimed water was assessed for potential industrial reuse. The methane yield from anaerobic digestion of dairy industry wastewater was 0.214 ± 0.008 mL CH₄/g COD_fed. The RO permeate quality met EPA standards, and the combined AnMBR + RO system operated at a cost of 0.46 €/m³. The findings of this study demonstrated that the AnMBR + RO system could produce treated water suitable for use as makeup water in cooling towers, offering a sustainable alternative for industrial water reuse and reducing the overall water footprint.