Study Of The Transformation Law Of Nitrogen During The Treatment Of Anaerobic Effluent Of Fresh Leachate From MSW Incineration Plant By A/OMBBR

The concentrations of NH4+-N in fresh leachate from municipal solid waste(MSW)incineration plant increased after the treatment of EGSB,it is necessary to have a deep denitrification treatment.In this thesis,an A/OMBBR reactor was used to study the influence of influent concentration of NH4+-N,COD/N,pH,temperature and reflux ratio on the transformation law of nitrogen during the treatment.We also determined the nitrification rate constant and denitrification rate constant through the dynamic experiment and analyzed the microbial community structure under the optimal operating condition.A lab-scale A/OMBBR was designed and built to study the transformation law of nitrogen during fresh leachate treatment under the condition of different combination.The results showed that under the optimal operating condition with the influent concentration of NH4+-N at 300 mg/L,COD/N at 4.2,pH at 8.5,temperature at 25?32? and reflux ratio at 300%,above 99%of NH4+-N and 80%of TN can be removed by the A/OMBBR system with the lowest N2O emission and NO2--N concentration during fresh leachate treatment.The transformation law of nitrogen in OMBBR were significantly effected by the influent concentration of NH4+-N,COD/N and pH;the transformation law of nitrogen in AMBBR were significantly effected by COD/N,pH and reflux ratio;the denitrification rate were significantly effected by the influent concentration of NH4+-N,COD/N,pH and reflux ratio during the treatment of anaerobic effluent of fresh leachate from MSW incineration plant by A/OMBBR.We determined the nitrification rate constant was 0.05257 mg/L/min and the denitrification rate constant was 0.2074 mg/L/min through the dynamic experiment.We found that the limited process of A/OMBBR was nitrifying process.And we can shorten the hydraulic retention time(HRT)of A/OMBBR system appropriately to improve the processing efficiency,because time needed to complete nitrification is far less than HRT of the system.The microbial community structure of packing biofilms samples in reactor was analyzed by high-throughput sequencing technologies.The results showed that the dominant bacteria were Thauera?Anaerolineaceae?Nitrospira and Nitrosomonas,and Thauera?Nitrospira and Nitrosomonas were the key species in the process of denitrification.The experimental results showed that the species which contribute to denitrification can be enriched on packing and can get good denitrification effect by using A/OMBBR during fresh leachate treatment.