Abstract
Qualitative effects of morphology of surface on behavior of biofilm were investigated by two-dimensional biofilm model with ideal rough surface which was numerically analyzed by finite element method. This model is presented by diffusion and double Monod-type microbial reactions in the biofilm and the diffusion layer can be included in the model. The biofilm was formed by acidophilic iron-oxidizing bacteria.
Effect of the roughness of surface on the increase rate of flux, which is the rate of substrate removal flux of biofilm with rough surface to that of plane biofilm, is significant when surface roughness is large. This effect is changed by substrate and dissolved oxygen concentration in bulk liquid and the influence of the concentration in bulk liquid is small when the surface roughness is large. The maximum rate of increase of flux approaches to the rate of increase of surface area of biofilm. Morphology and area of biofilm domain (IMFD) which has 99% of substrate removal flux is changed by the surface roughness and the concentration in bulk liquid. The rate of increase of flux becomes large when IMFD changes around the shape of rough surface.
