多级流化床-曝气生物滤池中试处理高氨氮废水

The combination pilot process of multi-stage fluidized bed-biological aerated filter was used to treat high-strength ammonia-nitrogen industrial wastewater. The start-up method of this pilot system and pollutants removal efficiency during its stable operation stage were studied, and its superiority over traditional activated sludge processes were also determined. The results showed that the start-up of this pilot system could be accomplished within about 50 d through controlling the flow rate and gradually elevating the inflow load. At the start-up stage, the removal efficiencies of COD and NH_4^+-N were 68.74% and 97.92%, respectively. The COD and NH_4^+-N concentrations in effluent were 176.35 mg•L^-1 and 13.52 mg•L^-1, respectively. At the stable stage with the flow rate of 2.0 m³•d^-1, the average removal efficiencies of COD and NH_4^+-N were 92.66% and 99.32%, respectively, and the average COD and NH_4^+-N concentrations in effluent were 152.24 mg•L^-1 and 1.32 mg•L^-1, respectively. Of which the NH_4^+-N concentration in effluent could meet the requirement of class IV water standard for surface water. Compared with the traditional activated sludge process, the pilot system of multi-stage fluidized bed-biological aerated filter could improve the COD and NH_4^+-N removal efficiencies from 85.37% to 92.66% and from 72.53% to 99.32%, respectively.