Synergistic approaches for effective estrogen degradation in wastewater treatment: wetland-UV/O3 pilot-scale investigation

The presence of estrogens in wastewater treatment plant effluent is increasingly recognized as a significant concern for environmental health. In this study, we showcase the efficacy of a pilot-scale 5 m³/d artificial wetland-UV/O₃ advanced oxidation treatment system in consistently achieving removal efficiencies exceeding 80 % for two key estrogens: nonylphenol and bisphenol A. Specifically, the system achieved average removal rates of 95.32 % for nonylphenol and 92.66 % for bisphenol An under optimal conditions where the constructed wetlands were combined with O₃ and fully open UV lamps. Additionally, this integrated system effectively reduced other pollutants, such as ammonia nitrogen (<1 mg/L), chemical oxygen demand (<20 mg/L), biochemical oxygen demand (<4 mg/L), total phosphorus (<0.2 mg/L), and color (less than 10° after UV/O₃ treatment). The design and operation of this innovative treatment process offer a promising solution for mitigating estrogen contamination in sewage treatment plant effluent. Furthermore, the experimental data gathered provide valuable insights for potential future scaling of this technology.