Nitrogen removal performance in a novel combined biofilm reactor

Experiments have been performed to investigate the nitrogen removal performance in a novel combined biofilm reactor using synthetic wastewater. In the reactor, one cubic box was separated by two baffles into three zones: aerobic zone, buffering zone and anoxic zone. Nitrification and denitrification were supposed to be mainly accomplished in the aerobic and anoxic zones, respectively. When the influent total nitrogen (TN) and organic carbon loadings were averaged at 0.093 and 0.40 kg/m3/d, 84% TN removal efficiency was achieved by adjusting the aeration rate and the configuration of the reactor. Continuous experimental results demonstrated that NH3-N removal efficiency increased by adjusting the clapboards of the reactor at a certain aeration rate. Energy produced by aeration was used for liquid recycle, so TN could be more efficiently removed at lower cost in this reactor.