Hui DENG soutiendra sa thèse en génie des procédés et de l’environnement intitulée : Towards an integrated combination of membrane processes and oxidation for the removal of micropollutants in wastewater and urine.

Jury : Christelle GUIGUI et Jean-Stéphane PIC  (INSA-LISBP encadrants), Annabelle COUVERT (ENS  Chimie Rennes),  Julie MENDRET (Institut Européen des Membranes, Montpellier),  Wolfgang GERNJAK (Catalan Institute for Water Research), Isabelle POLAERT (Lab.  Sécurité des Procédés Chimiques -INSA- Rouen)

RESUME : Advanced technologies, such as reverse osmosis (RO) and ozonation, need to be established to eliminate micropollutants and to produce high-quality water for wastewater reuse. The present thesis aims to assess the potential of RO process and ozonation for the removal of pharmaceutically active compounds (PhACs) from municipal membrane bioreactor (MBR) permeate and urine. RO is used to retain inorganic and organic compounds from wastewater. Ozonation allows to degrade micropollutants present in the wastewater. The results showed that RO membrane in MBR-RO system with RO concentrate recycling maintains a relatively stable and effective retention capacity for the global water quality parameters. However, after RO concentrate recycling, the fouling propensity of RO membrane was enhanced in terms of permeate flux decline, which was mainly due to an increased osmotic pressure of ions at the RO membrane surface. In addition, ozonation was a feasible solution to manage RO concentrate. With respect to urine treatment, struvite precipitation was successful in recovering P nutrients from urine. However, most of target PhACs still remained in the urine effluents after the struvite precipitation and ozonation was applied for their removal. As compared to the ozonation of saline solution with ions and synthetic urine (containing ions and ammonia), a higher ozone dose was required to remove the same quantity of target PhACs from real urine solutions (containing ions, ammonia and organic matters), mainly due to the competitive reactions of salts, ammonia and organic matters with molecular ozone.