Performance of Ozonation Process as Advanced Treatment for Antibiotics Removal in Membrane Permeate

There was an investigation into the removal of 6 types of antibiotics from hospital wastewater through membrane bioreactor (MBR) treatment and ozonation processes. Six types of antibiotics, namely, Sulfamethoxazole (SMZ), Norfloxacin (NOR), Ciprofloxacin (CIP), Ofloxacin (OFL), Erythromycin (ERY), and Vancomycin (VAN) which had high detection frequencies in collected samples from hospital wastewater treatment plant (HWTPs). After MBR treatment, the removal efficiencies of SMZ, NOR, OFL, and ERY were 45%, 25%, 30%, and 16%, respectively. Among of them, almost no elimination was observed for CIP and VAN since their concentrations increased by 0.24 ± 0.18 (μg·l-1) and 0.83 ± 0.20 (μg·l-1), respectively. Then, residues of the antibiotics were removed from the MBR effluent by the ozonation process. The overall removal efficiencies of SMZ, NOR, CIP, OFL, ERY, and VAN were approximately 66 %, 88 %, 83 %, 80 %, 93 %, and 92 %, respectively. The reason might be depended on different ozone consumption of those antibiotics (ABS) in a range of 313 to 1681 μg ABS·gO--1. Consequently, the ozonation process performed better in the antibiotics removal (e.g. CIP and VAN) so ozonation could be considered as important support for the MBR treatment to reduce the risk of antibiotic residues.