Emerging contaminants removal by full-scale ozonation tertiary treatment
Elimination des micropolluants par ozonation (station des bouillides)
Résumé
Dissemination of chemical substances in the environment is becoming a major issue and wastewater effluents are one the main point sources. The goal of the present work was to determine the performances on micropollutants removal of a recently developed process consisting in ozone contactor followed by a post-denitrification submerged biofilter. A full-scale tertiary treatment line (600 m3/h) built at Sophia-Antipolis wastewater treatment plant (WWTP) was studied under various operating conditions (ozone and methanol dosage). The groups of micropollutants monitored include pharmaceuticals, hormones pesticides (domestic uses) and also compounds listed in the European Union Water Framework Directive such as metals, phthalates (DEHP) and alkylphenols. Preliminary results show that with an ozone dosage of 5 g/m3, the tertiary treatment line achieved high removal rate of pharmaceutical compounds (higher than 70%). Diuron removal was also mainly due to the tertiary treatment (50% elimination). Environmental performance of this tertiary treatment was assessed thanks to a life cycle analysis.