Removal of Synthetic Estrogens in Attached Growth System

Abstract

Effective treatment of wastewater is crucial to reduce the impact of industry and human activities on the environment. Thus, a more efficient water treatment is needed to remove the components of waste, or the pollutants, faster. Hence in the case of this study, the aim was to investigate the use of bio-filters to remove ammonia-nitrogen and endocrine disrupters (17α-ethynylestradiol, the EE2, and mestranol, the MeEE2) in a batch culture experiment. The initial concentrations of 100 µg/L of EE2 and 100 µg/L of MeEE2 were prepared and added to the batch reactor with bio-filters. The bio-filters contained four concentrations of ammonia-nitrogen which were 35 mg/L, 65 mg/L, 85 mg/L and 100 mg/L. The results showed that with 35 mg/L of ammonia-nitrogen, the concentration of the EE2 and the MeEE2 was reduced to 30 µg/L showing 70% of them removed over the incubation period. Whereas with 65 mg/L of ammonia-nitrogen, the EE2 and MeEE2 were reduced to 27 µg/L and 22 µg/L, of which 73% of the EE2 was removed while the MeEE2, 78%. Thirdly, with 85 mg/L ammonia-nitrogen, the concentration of both oestrogens was reduced nearly the same, which was the EE2 16 µg/L and the MeEE2 14 µg/L. Here, 84% of the EE2 was removed and the MeEE2, 86%. Lastly, using 100 mg/L of ammonia-nitrogen, the concentrations of the EE2 and the MeEE2 were reduced to 11 µg/L and 14 µg/L, thus removing 89% of the former and 86% the later. These results displayed the highest removal of oestrogens in comparison with other experiments at different initial concentrations of ammonia-nitrogen in the attached growth system of bio-filters. Â