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The end of China's urban sewage treatment plants, water with a low C / N, N, and P content is high, and its depth of nitrogen and phosphorus removal has a certain degree of difficulty. In this paper, the process of the new simultaneous nitrification and denitrification, partial nitrification and denitrification denitrification technology-based biological activated carbon filter (BACF), to strengthen the the BACF process denitrification effect. In contrast the different particle size of the filler the BACF process decontamination effect test obtained under the same experimental conditions, the small particle size filler (having a diameter of (φ1.5mm, a length of 2 ~ 4mm columnar granular activated carbon) BACF and large particle size filler (diameter φ4mm, columnar granular activated carbon for 4 ~ 10mm in length) BACF hanging membrane start-up and stable operation of pre efficient the removal COD.NH4-N, but the small particle size filler BACF more advantages, but in the long-term stability running, large particle size filler the BACF decontamination effect is more stable. stable running late, small particle size filler the BACF appears filter compaction phenomenon, and water quality deterioration. ensure the stable operation of the process system, reducing backwash cycle and backwash power, reduce energy consumption, the follow-up test using large particle size of activated carbon filler. using simultaneous nitrification and denitrification process simulation of urban wastewater treatment plant tailrace test BACF draw system for optimum operating conditions: T: 25 ± 1 ° C; gas water ratio of 4; DO: 2.5 to 3.5mg / L; hydraulic loading: 9m3 / (m2.d); pH value: 7.5 to 8.0, packing height of 70cm, this time the effluent COD. NH4-N TN concentrations were 10.3mg / L, 1.0mg / L, 16.6mg / L, the removal rate were 86.7%, 92.9%, 36.2%. effluent COD, NH4-N concentration meet design effluent quality standards, but TN does not meet the design water quality requirements. BACF simultaneous nitrification and denitrification denitrification capacity is limited. based on the tailrace test shortcut nitrification and denitrification theory of pre-denitrification the BACF Process simulation of urban wastewater treatment plant, through the analysis of the processes influencing factors to determine the system dealing with the simulation of urban sewage treatment plant tailrace best operating conditions: air-water ratio: 2; pH: 7.5 ± 0.2; temperature: 25 ± 1 ° C; reflux ratio: 200%; hydraulic loading: 11.3m3 / (m2. d), under these conditions, processes an average of COD, NH4-N and TN concentrations were: 10.7 mg / L, 1.2mg / L, 10.6 mg / L, the average removal rates were: 88.2%, 92.5%, 71.2% The process effluent of COD, NH4-N, TN meet the design water quality standards, but under these conditions the process average effluent TP concentration of 1.3 mg / L, the removal rate of 45.6%, can not meet the design water quality standards should be consider the effect of subsequent coagulation and sedimentation the phosphorus removal strengthen the system phosphorus removal.
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