Publication
The removal efficiency for 220 micropollutants was studied at the scale of a municipal wastewater treatment plant (WWTP) upgraded with post-ozonation followed by sand filtration. During post-ozonation, compounds with activated aromatic moieties, amino functions, or double bonds such as sulfamethoxazole, diclofenac, or carbamazepine with second-order rate constants for the reaction with ozone >10(4) M-1 s(-1) at pH 7 (fastreacting) were eliminated to concentrations below the detection limit for an ozone dose of 0.47 g O-3 g(-1) dissolved organic carbon (DOC). Compounds more resistant to oxidation by ozone such as atenolol and benzotriazole were increasingly eliminated with increasing ozone doses, resulting in >85% removal for a medium ozone dose (similar to 0.6 g O-3 g(-1) DOC). Only a few micropollutants such as some X-ray contrast media and triazine herbicides with second-order rate constants 100 ng L-1. The combination of reaction kinetics and reactor hydraulics, based on laboratory and full-scale date, enabled a quantification of the results by model calculations. This conceptual approach allows a direct upscaling from laboratory- to full-scale systems and can be applied to other similar systems. The carcinogenic by-products N-nitrosodimethylamine (NOMA),(