Enhancing membrane bioreactors for dairy effluent treatment with a mixed mobile bed application

Abstract

This study examines the impact of incorporating a mobile bed into a membrane bioreactor (MBR) system on the treatment efficiency of dairy industry effluents. Initially, a conventional MBR system was operated for 60 days, followed by a modification that included a support material and ran for another 60 days under identical conditions. Performance was evaluated based on the removal efficiencies for soluble chemical oxygen demand (CODs), phenolic compounds, and oils and greases (OG), alongside measurements of solid content, dissolved oxygen, temperature, mixed liquor pH, and transmembrane pressure (TMP). The introduction of the mobile bed led to an increase in removal efficiencies for COD and phenolic compounds from 94.4 and 92.7% to 98 and 94.4%, respectively, marking statistically significant improvements (p 0.05). Moreover, the modified system showed a more stable TMP profile, reducing the need for cleaning interventions compared to the conventional system, which experienced a notable TMP increase requiring cleaning at a 0.6 bar threshold. The findings suggest that integrating a mobile bed into MBR systems significantly enhances the treatment of dairy effluents, presenting an interesting solution for the upgrade of this type of system. HIGHLIGHTS The integration of a mobile bed into MBR systems significantly increases the removal efficiency of phenolic compounds.; Modified MBR systems with a mobile bed significantly reduce membrane fouling, making MBR operation more stable.; Integrating a mobile bed offers a promising upgrade for dairy effluent treatment.;

Keywords

• biofilm reactors
• membrane fouling
• nutrient removal
• phenolic compounds
• wastewater reclamation