HETEROTROPHIC DENITRIFICATION USING FLUIDIZED-BED REACTOR

Groundwater denitrification was carried out in a fluidized bed reactor. This type of reactor is suited well to conditions of low substrate concentrations and high flow rates which are typical in groundwater denitrification processes. The reactor is characterized by the efficient contact between biomass and substrate, a high biomass concentration, and the absence of clogging or channeling. These characteristics provide for high treatment capacities (10.8 g/(L.d) NO3--N) and short retention times (less than 3 minutes) resulting in small reactor volume. Start-up procedure, biomass and nitrate profiles, and biofilm characteristics are presented in this article.