Mourad, benneouala le Jeudi 4 mai 2016 à 14h30 En Salle des thèses (insa)

ECOLE DOCTORALE

« Mécanique, Energétique, Génie Civil, Procédés »

ED 468

Vous êtes cordialement invités à la soutenance de la thèse de
Mourad, BENNEOUALA
Le Jeudi 4 mai 2016 à 14h30
En Salle des thèses (INSA)
Titre:
Biodegradation of slowly biodegradable organic matter in wastewater treatment plant (WWTP): In depth analysis of physical and biological factors affecting hydrolysis of large particles

Résumé
In this work, the fate and biodegradation of slowly biodegradable organic matter contained in wastewaters were investigated. The hydrolysis process was particularly targeted as many sources proved that it controls the fate of the considered substrate. First, a synopsis of the literature results related to this topic as well as internal results were investigated especially in terms of respirometric aspects (OUR measurement) in order to identify differences and/or similarities between the experiments and, thus, address gaps in knowledge of the mechanisms that are involved in the hydrolysis of this matter. Then, in the second part of this thesis, experimental data from batch respirometric tests (performed in our laboratory), involving typical slowly biodegradable matter that are found in wastewaters (e.g. Particulate settleable solids, toilet paper…), were confronted to conventional (IAWQ models) and non-conventional (but existing) models to evaluate the efficiencies of those models to describe the hydrolysis step. In the third part of this thesis, based on hypotheses (e.g. microscopic observations), a novel conceptual framework was developed in order to enhance the description of the hydrolysis process. The physical properties (density, size, shape) of the components (bacteria and substrate) were taken into account in this model. Finally, in the fourth and last chapter of this work, the specific role of each bacterial population (hydrolytic, active but not hydrolytic, passive, initially adsorbed to the substrate…) involved in the biodegradation of slowly biodegradable organic matter was assessed. It was here clearly evidenced that the hydrolysis of PSS in activated sludge processes appears more influenced by the initially adsorbed bacteria onto the sewage than by the added AS-inoculum concentration.
Mots-Clés :
Wastewater treatment, particulate settleable solids, slowly biodegradable organic matter, hydrolysis, respirometry, modeling
Etablissement d’inscription :
INSA de Toulouse


Composition du Jury :
Yolaine Bessiere, Maître de conférences (co-directrice de thèse)

Etienne Paul, professeur (directeur de thèse)

Mathieu Spérandio, professeur (examinateur)

Yoan Pechaud, maître de conférences, Université Paris-Est (examinateur)

Elisabeth Girbal-Neuhauser, professeur, LBAE Auch (examinateur)

Nicolas Derlon, directeur de recherche EAWAG Zurich (examinateur)

Sylvie Gillot, directeur de recherche IRSTEA Lyon (rapporteur)

Nicolas Bernet, directeur de recherche INRA-LBE Narbonne (rapporteur)