PREDICTION OF AVERAGE BIOFILM DENSITY AND PERFORMANCE OF A SPHERICAL BIOPARTICLE UNDER SUBSTRATE-INHIBITION

In this article, a model was proposed to predict the average performan ce and biofilm density of a spherical bioparticle under substrate inhi bition in a fluidized bed system. The average biofilm density and subs trate consumption rates were predicted for a definite biofilm thicknes s and limiting substrate concentrations. A diffusion and reaction mode l was developed over the bioparticle with biofilm-density dependent ef fective diffusion coefficients for maximum substrate consumption theor y. This theory predicts the optimum density of a biofilm to yield a ma ximum substrate consumption rate within the biofilm, developed for the first time with this study and experimentally verified. A good correl ation was observed between the model prediction and experimental resul ts for biofilm density and substrate consumption rates. (C) 1997 John Wiley & Sons, Inc.