| Short nitrification-denitrification is that as soon as NH4+is oxidized to NO2-, NO2- is reduced to N2,without the reaction process of NO2- to NO3- and NO3- to NO2-. It has the following superiority compared with conventional technology from theory calculation.(1)In the process of nitrification,it can save oxygen demand by 25% and reduce energy consumption. (2)In the process of denitrification it can reduce organic carbon sources by about 40% and cut down the operating cost. (3)The reaction speed of NO2--N is usually higher than NO3--N by about 63%.(4)It can reduce sluge output by about 50%.(5)The reactor containers can be reduced by about 30%～40%.(6)It can reduce the requirement of alkalinity and external carbon source.The paper studied on influencing factors of short nitrification and operation paraters regulation and Nitrogen removal effect of three different short nitrification- denitrification technology and the kinetic model of short nitrification- denitrification was built up.The experimental results show that:1)In the SBR,when DO concentration was 2.0mg/L and 50 to 450mg /L of ammonia nitrogen were filled step by step,the nitrite could be reached stably in 39 days,99%of ammonium was removed at 25℃, the value of pH 7.5~8.6.2)The Short-cut nitrification process of high ammonia wastewater(concerntration of ammonia is 450mg/L) in SBR was stable when low DO(0.3～1.0mg/L) was obtained.In this condition, both nitrite accumulation rates and ammonia removal efficiencies were higher than 80%.3)The effect of alkali was studied. When the concentration of ammonia was 450mg/L, and the dosage of CaCO3 was 23.81g, shortcut-nitrification is quickly attained. Ammonia removal efficiencies wase higher than 98% and nitrite accumulation rates were steadily higher than 85%.4)After the conventional denitrification got into a stable state, the short-cut denitrification was realized successfully in SBR by changing pH and DO. e.And compared with SHAPON technics, which was opened out by the University of Netherlands Delft, the system is more pratical.5)When studing the effect of reflux ratio (50%and80%) on TN removal in the A/O, A/O/A (endogenous)/O and A/O/A (exogenous)/O systems. The experiment indicated that: A/O achieved TN removal rate of 40% , A/O/A (endogenous)/O achieved TN removal rate of 45% and A/O/A (exogenous)/O achieved TN removal rate of 60%. 6) Analyzing the short-cut nitrification pocess, we built up the kineticmodel of short-cut nitrification.The parameters of the kinetic model was compulated base on the data of experiment.The result as follow:7)Analyzing the shortcut denitrification pocess, we built up the kinetic equation of shortcut denitrication.The parameters of the kinetic model was computed base on the data of experiment.The result as follow:The result showed that in this test the concentration of COD and NO2- -N were higher than their saturation constants respectively.Therefore,the shortcut denitrification in this paper was zero-order kinetic reaction.The denitrification rate was the function of temperature and PH.
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