摘要
A system consisting of a two-stage up-flow anaerobic sludge blanket （UASB）, an anoxic/aerobic （A/O） reactor and a sequencing batch reactor （SBR）, was used to treat landfill leachate. During operation, denitrification and methanogenesis took place simultaneously in the first stage UASB, and the effluent chemical oxygen demand （COD） was further removed in the second stage UASB. Then the denitrification of nitrite and nitrate in the returned sludge by using the residual COD was accomplished in the A/O reactor, and ammonia was removed via nitrite in it. Last but not least, the residual ammonia was removed in SBR as well as nitrite and nitrate which were produced by nitrification. The results over 120 d （60 d for phase I and 60 d for phase II） were as follows： when the total nitrogen （TN） concentration of influent leachate was about 2500 mg/L and the ammonia nitrogen concentration was about 2000 mg/L, the shortcut nitrification with 85%-90% nitrite accumulation was achieved stably in the A/O reactor. The TN and ammonia nitrogen removal efficiencies of the system were 98% and 97%, respectively. The residual ammonia, nitrite and nitrate produced during nitrification in the A/O reactor could be washed out almost completely in SBR. The TN and ammonia nitrogen concentrations of final effluent were about 39 mg/L and 12 mg/L, respectively.
A system consisting of a two-stage up-flow anaerobic sludge blanket （UASB）, an anoxic/aerobic （A/O） reactor and a sequencing batch reactor （SBR）, was used to treat landfill leachate. During operation, denitrification and methanogenesis took place simultaneously in the first stage UASB, and the effluent chemical oxygen demand （COD） was further removed in the second stage UASB. Then the denitrification of nitrite and nitrate in the returned sludge by using the residual COD was accomplished in the A/O reactor, and ammonia was removed via nitrite in it. Last but not least, the residual ammonia was removed in SBR as well as nitrite and nitrate which were produced by nitrification. The results over 120 d （60 d for phase I and 60 d for phase II） were as follows： when the total nitrogen （TN） concentration of influent leachate was about 2500 mg/L and the ammonia nitrogen concentration was about 2000 mg/L, the shortcut nitrification with 85%-90% nitrite accumulation was achieved stably in the A/O reactor. The TN and ammonia nitrogen removal efficiencies of the system were 98% and 97%, respectively. The residual ammonia, nitrite and nitrate produced during nitrification in the A/O reactor could be washed out almost completely in SBR. The TN and ammonia nitrogen concentrations of final effluent were about 39 mg/L and 12 mg/L, respectively.
基金
supported by the Project of Beijing Natural Science Foundation (No. 8091001)
the National Natural Science Foundation of China (No. 50978003)
the Higher Learning under the Jurisdiction of Beijing Municipality (No. PHR20090502)
the State Key Laboratory of Urban Water Resource and Environment (HIT) (No.QAK200802)
