Bifurcation and stability analysis of a two step model for monitoring anaerobic digestion processes

Brahim Benyahia (1, 2) , T. Sari (2, 3) , B. Cherki (1) , Jérôme Harmand (2, 4)

1 LSDA - Laboratoire Systèmes Dynamiques et Applications
2 MODEMIC - Modelling and Optimisation of the Dynamics of Ecosystems with MICro-organisme
3 UMR ITAP - Information – Technologies – Analyse Environnementale – Procédés Agricoles
4 LBE - Laboratoire de Biotechnologie de l'Environnement [Narbonne]

This paper deals with the equilibria and stability analysis of the two step anaerobic model initially proposed by [12] to describe the dynamical behavior of an anaerobic fixed-bed wastewater treatment process. In a first part, the model is analyzed: its equilibria and their stability are established considering qualitative properties of the kinetics. In a second part, it is shown that the overloading tolerance (denoted herein OT), a parameter proposed in [9] to monitor anaerobic processes on-line, may not be suitable for monitoring the system and even causes serious problems under certain functioning conditions. Based on the analysis results established in the first part, a modified OT is proposed and evaluated in simulation.

Mots clés: BIOTECHNOLOGIE; DIGESTION ANAEROBIE; EQUILIBRE; THEORIE DE L'APPROXIMATION; EVALUATION DES RISQUES; STEADY STATE ANALYSIS

Domaines: Sciences de l'environnement

Brahim Benyahia, T. Sari, B. Cherki, Jérôme Harmand. Bifurcation and stability analysis of a two step model for monitoring anaerobic digestion processes. Journal of Process Control, 2012, 22 (6), p. 1008 - p. 1019. ⟨10.1016/j.jprocont.2012.04.012⟩. ⟨hal-00777051⟩