Effect of Sulfamethoxazole and ZnO NPs on Sludge Activity
PPCPs as emerging pollutants that have been widely recognized in recent years,have attracted the attention of all sectors of society.This study used a sequencing batch reactor(SBR)in anoxic/aerobic(AO)operation mode to investigate the effects of coexistence of antibiotics and nanomaterials on activated sludge systems and to provide a theoretical basis for promoting the stable operation of wastewater treatment systems.Results showed that the coexistence of sulfamethoxazole(SMZ)and ZnO nano-particles(NPs)reduced the MLSS and MLVSS/MLSS in the SBR reactor by 17.67%and 9.73%,respectively,and the sludge activity was suppressed.Further studies showed that compared to the blank group,the polysaccharide and protein content of the SMP in coexistence system in the sludge effluent increased by 39.0%and 63.3%and reduced the biological phosphorus removal capacity of the phosphorus-polymerising bacteria,thus affecting the treatment efficiency.Finally,this study investigated the variations in microbial activity through reactive oxygen species(ROS),adenosine triphosphate(ATP)and lactate dehydrogenase(LDH)indices.Results showed that the coexistence of SMZ and ZnO NPs produced significant inhibitory effects on ROS,ATP and LDH.