Abstract
A biofilm model was presented to investigate the design and operation factors of the bio-electro reactor on nitrification. The biofilm model consists of molecular diffusion, substrate utilization and electrochemical reaction. The concept of an effectiveness factor (Ef) was introduced to estimate the effects of applying electric current. The mathematical model showed that the effect of applying electric current was large when bulk DO concentration is low and biofilm is thick. Both the calculated and observed results also showed the possibility of a simultaneous nitrification-denitrification treatment in a single bio-electro reactor. The electrochemically enhanced nitrification rate calculated using the biofilm model was comparable to the experimental result.
