Eliminación de nitrógeno de aguas residuales y agua para el consumo en un biorreactor de lecho fluidizado

is replaced by a new concept in which the two processes are performed together in a single high-performance fluidized-bed. Based on the former nitrifying reactor, new equipment was designed. This reactor contained a fluidized bed with separated aerobic and anoxic sections for nitrification and denitrification respectively. This was accomplished by the use of different-diameter sand as carrier material and appropriate reactor shape, recirculation, feed and aeration conditions. The reactor (20 L fluidized-bed volume) was operated for 3 months. It was fed with synthetic waste water (50 L/h) containing 25-40 mg NHPropionic acid and ethanol in a 1:4 ratio were used as the carbon source (2.3 g C/L) for denitrification, fed in at different points of the reactor. Ammonium removal reached 50%, while denitrification was 75%. The total nitrogen removal rate was 0.8-1.2 kg N/mA new simple hydrostatic pressure method was used to monitor biofilm thickness in the fluidized bed. During the experiments the oxidation-reduction potential (ORP) was tested as a tool to monitor reactor performance; its use for the control of the process was found to be limited.