Research On The Temporal And Spatial Distribution Of Nitrogen Forms And Nitrogen Removal Of Low C/N Ratio Sewage In The CIBR

In recent years,with the aggravation of the water eutrophication, the discharge standard of nitrogen has been more and more stringent. However, a higher requirement has been raised due to the lack of carbon source while the nitrogen source is excess generally. The traditional process in dealing with wastewater of low C/N ratio is inefficient owing to shortage of the carbon source. What is worse,the new technique is immature. So there are many problems in engineering application, and it has been a conundrum if you want to denitride the low C/N ratio sewage efficiently.In order to denitrify the low C/N ratio sewage efficiently, the nitrogen removal effect of the CIBR(Continuous flow Integrated Biological Reactor) and the temporal and spatial distribution discipline of the nitrogen is aquired by monitoring the nitrogen concentration in the reactor and effluent at intervals of some hours,and obtaining the mechanism of nitrogen removal based on the temporal and spatial distribution of the nitrogen forms: (1) In the 2+2 model, the COD,TN,NH4+-N in the effluent of the CIBR can achieve stability at the national level A discharge standard when the C/N ratio of the influent is 3.4,5.2. (2) The unhomogeneous C/N ratio in the CIBR and the point aeration at the bottom makes CIBR to achieve high efficient biological nitrogen removal facing the influent of low C/N ratio. (3) Simultaneous Nitrification Denitrification was found in the the reactor during the aeration stage based on the analysis of the theory about micro-environment and macroeconomic environment. (4) Nitrification and denitrification dynamic model are attained by the analysis of kinetics about nutrient removal. Ammonia-N degradation rate constant K, nitrate nitrogen degradation rate constant KN in aeration stage and denitrification rate constant KD in agitation stage are calculated to be 1.152h-1, 0.101h-1 and 0.368h-1 respectively based on the data of the pilot scale.These rate constants prove that the Simultaneous Nitrification Denitrification exists in the CIBR.This paper confirms the predominance of CIBR in sewage of low C/N ratio treatment. Therefore, the CIBR in the treatment sewage of low C/N ratio should have a very good prospect.