Abstract

Silver nanoparticles discharged from wastewater treatment plants pose potential risks to aquatic environments and in long term it may cause serious human health issues, hindering life quality. Limited research has been developed, making it difficult to ensure efficient removal of silver nanoparticles in wastewater treatment plants. This study evaluates silver nanoparticles removal efficiency across different wastewater treatment plant layouts: conventional activated sludge, an anaerobic/oxic process configuration, and a 4-stage Bardenpho process system. Silver nanoparticle removal efficiency was 82% and nitrogen removal efficiency exceeded 95% under steady state conditions; however, under dynamic conditions, a significant reduction was observed in the Bardenpho and anaerobic/oxic configurations. The results also showed variability in organic matter and nitrogen removal due to reduced internal recirculation flowrates. The findings highlight the need to optimize certain configurations to ensure balanced performance across all pollutants.