PARAMETERS AFFECTING NITRIFYING BIOFILM REACTORS

The variables affecting nitrification in biofilms are identified on a theoretical basis. The influence of various design and operational par ameters which affect the resulting substance fluxes into and out of th e biofilm and the biomass activity regarding nitrification are illustr ated with the help of experimental investigations with plastic media t rickling filters, rotating biological contactors and different aerated biofilters. The results of experiments with these systems in tertiary nitrification applications reveal process limitations and technical m easures to enhance nitrification performance in each system. In a case study, a comparison between the different biofilm processes and activ ated sludge alternatives showed that biofilm systems may lead to remar kably smaller reactor volumes, but high energy consumption due to unfa vorable oxygen utilization.