Removal of organic matter and nutrients from wastewater by the combined submerged biofilter and activated sludge processes

Abstract

An activated sludge reactor was integrated into an anoxic-aerobic submerged biotilter process to improve its performance. The reactor integrated was divided into a small sedimentation and activated sludge compartments. To enhance settling characteristics of the sedimentation basin, an inclination plate was set. From the laboratory experiment, angle of the inclination plate and distance between the divider and inclination plate were approximately 70° and 2 cm, respectively. It was also concluded from the laboratory experiment that performance of activated sludge process was higher than that of submerged biofilter process on COD removal and nitrification. After completing the laboratory experiments, the pilot-scale experiment was carried out using a plant based on the principle of the anoxic-aerobic submerged biofilter process. Primary aerobic compartment of the pilot-scale plant was used as submerged biofilter or activated sludge tanks. As the results obtained in the laboratory experiments, nitrification performance of the plant was increased by using the primary aerobic compartment as the activated sludge tank.