Treatment of urban highly polluted water by composite biofilter
复合生物滤池处理城市高污染水体

A pilot-scale composite biofilter was developed to treat the urban highly polluted water. The study was conducted to investigate the optimal operation parameters of biofilter and the removal efficiency of nitrogen and organic matter. The results show that the volume loading, hydraulic loading and ventilation ratio should be controlled at 0.3 to 0.5 kg COD/(m3·d), 4.5 to 5 m3/(m2·d) and 9%, respectively. With the C/N ratio of 5 to 8,the average removal rates of COD, NH4+-N and TN were 80%, 87% and 63%, respectively, which achieved the efficient state of simultaneous nitrification and denitrification.