Mechanisms of synergistic membrane fouling control and pollutants removal in a Plasma-Assisted membrane bioreactor for antibiotic wastewater treatment.

This study developed an integrated process coupling dielectric barrier discharge (DBD) pretreatment with a membrane bioreactor (MBR) for treating tetracycline (TC)-containing wastewater. The results demonstrated that DBD pretreatment effectively degraded more than half of TC, reduced transmembrane pressure, and decreased the average membrane fouling rate by 16%. Systematic analysis revealed that the sludge in the DBD-MBR system maintained stable mixed liquor suspended solids and sludge volume index, while the contents of extracellular polymeric substances and quorum-sensing signal molecules (C6-HSL and C8-HSL) were significantly reduced, which contributed to the mitigation of membrane fouling. Furthermore, DBD pretreatment markedly alleviated the oxidative stress induced by TC, as evidenced by the decreased reactive oxygen species generation, lactate dehydrogenase and superoxide dismutase activities. Microbial community analysis indicated that the DBD-MBR system maintained a more stable and diverse microbial structure compared to the conventional MBR. These findings confirm that the integration of DBD with MBR provides a sustainable and efficient strategy for the treatment of antibiotic wastewater by simultaneously enhancing biodegradation and controlling membrane fouling.