BIOFILM KINETICS AND THE PERFORMANCE OF A SINGLE SUBMERGED ATTACHED GROWTH BIOREACTOR FOR SIMULTANEOUS REMOVAL OF ORGANICS AND NITROGEN

The use of a single-unit, single-zone submerged attached growth bioreactor (SAGB) for the combined removal of carbonaceous organics and nitrogen from a municipal wastewater was demonstrated. A nitrification efficiency of 97% was achieved at a total organic loading of 3.47 kg-bCOD/m3–day. The total nitrogen loading varied from 0.2 kg-N/m3–day to 0.3 kg-N/m3–day, and resulted in effluent total nitrogen concentrations ranging from 4.2 mg/L to 8.5 mg/L. Concurrent denitrification was achieved at rates ranging from 0.077 kg-N/m3–day to 0.29 kg-N/m3–day. This single-unit SAGB, by providing dual treatment capacities, represents a cost-effective option that is particularly attractive for facilities with limited space and budget for system upgrade.