DYNAMICAL MODELING OF AN ANAEROBIC-DIGESTION FLUIDIZED-BED REACTOR

One of the main difficulties in modelling a Fluidized Bed Biofilm Reac tor (FBBR) is to take into account hydraulic phenomena (such as bed ex pansion) and its interactions with the biological variables. In this p aper, we shall present a dynamical model of the process, analyse the s tability of the hydrodynamics and illustrate its performances in simul ation, A key feature of the model is that it combines mass balance of the process components with momentum balance equations in order to emp hasise the different hydrodynamics of the liquid phase and of the soli d phase, and the interactions between both phases, The model derivatio n finally leads to a set of partial differential equations (PDE), This model is intended to be used as a basis for the derivation of control lers and for dynamical simulation. (C) 1997 IAWQ. Published by Elsevie r Science Ltd.