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 c oncentrations and high flow rates which are typical in groundwater den itrification processes. The reactor is characterized by the efficient contact between biomass and substrate, a high biomass concentration, a nd the absence of clogging or channeling. These characteristics provid e for high treatment capacities (10.8 g/(L.d) NO3--N) and short retent ion times (less than 3 minutes) resulting in small reactor volume. Sta rt-up procedure, biomass and nitrate profiles, and biofilm characteris tics are presented in this article.