Effect of electrocatalytic ozone coupled with bioactived carbon process on removal of carbamazepine and microbial community in wastewater

This study focused on the effluent from the secondary sedimentation tank of a municipal wastewater treatment plant in a southern city of China. The degradation effect of the advanced oxidation section and the bioactive carbon section of the system on the epileptic drug carbamazepine was evaluated by constructing an integrated pilot system with electrocatalytic ozonation+bioactivated carbon(E-H2O2/O3-BAC) as the core process. The bacterial community compositions of effluent from the different sections of the process were further analyzed. The results showed that the removal efficiencies of carbamazepine by the individual O3 process and the E-H2O2/O3 process were 95% and 90%, respectively. After passing through the BAC stage, the removal efficiency of carbamazepine exceeded 99% for both processes. The predominant potentially pathogenic bacterial genera detected in the sand-filtered effluent included Arcobacter, Pseudarcobacter, Bacteroides, Legionella, and Flavobacterium. The relative abundances of these genera exhibited significant changes (p<0.05) after different treatment processes. Although the E-H2O2/O3-BAC process was less effective in disinfecting pathogenic bacteria compared to the O3-BAC process, it did not lead to a significant increase in the relative abundance of Flavobacterium. Therefore, the E-H2O2/O3-BAC advanced treatment process could serve as an effective technique for the removal of emerging contaminants and microbial safety assurance in wastewater treatment plants. It showed great potential in the field of wastewater advanced treatment.