Driving competition in a complex ecosystem: application to anaerobic digestion

Pierre Masci (1) , Olivier Bernard (1) , Frédéric Grognard (1) , Eric Latrille (2) , Jean-Baptiste Sorba (2) , Jean-Philippe Steyer (2)

1 COMORE - Modeling and control of renewable resources
2 LBE - Laboratoire de Biotechnologie de l'Environnement [Narbonne]

—Anaerobic digestion is a wastewater treatment process where bacteria degrade an organic substrate and produce methane, which can be used as a biofuel. The first task when starting up an anaerobic digester is the increase of its microbial population. It is a delicate phase, which is still not well understood, and its influence on the digester's future performance is not well known. During this phase, we show that a competition between the various species occurs and finally some species become dominant. In this paper, extending the competitive exclusion principle, we propose to drive the competition during this start-up phase, by regulating the volatile fatty acids concentration, with the aim of selecting species with good performance in the standard operating mode of the process. This new "selective" start-up strategy should lead to more efficient ecosystems.

Mots clés: Anaerobic digestion; Bioreactors; Biological systems; Competition; Selection; Directed Evolution

Domaines: Optimisation et contrôle [math.OC]; Automatique

Pierre Masci, Olivier Bernard, Frédéric Grognard, Eric Latrille, Jean-Baptiste Sorba, et al.. Driving competition in a complex ecosystem: application to anaerobic digestion. European Control Conference, Aug 2009, Budapest, Hungary. ⟨hal-01091826⟩