Study On The Control Factors Of Short-cut Nitrification Under The High Ammonia Concentration Wastewater

Recently the nitrogen pollution in water bodies was becoming increasingly serious, and the ammonia nitrogen effluent standard was more and more strict, which would be regulated. So it was essential to research and develop more economic and effective wastewater treatment technologies.Among a variety of new nitrogen removal processes studied at home and abroad, short-cut nitrification-denitrification water treatment technology was focused on its advantages, such as saving energy, carbon resources and shortening hydraulic residence time, and reducing the amount of sludge-discharging.In this study, the low C/N synthetic high ammonia nitrogen wastewater was treated in Sequencing Batch Reactor (SBR). The startup and running control of short-cut nitrification was studied systematically; and the running effect of SBR short-cut nitrification was observed and studied under different temperatures and ammonia nitrogen concentrations, and the kinetic equation of the short-cut nitrification was established finally. The main conclusions are as follows:(1) The temperature in the SBR was 30-25℃,the aeration is controlled in 180L/h, SRT is 12d and a low influent C/N. The nitrosation reaction with ammonia removal efficiency was 90% and the accumulation of nitrite nitrogen was more than 80%, and completed the startup of SBR short-cut nitrification successfully. The higher stability, shock resistance was achieved in this systerm,which appeared a good startup effect.(2) At the end of short-cut nitrification, the"ammonia valley" of pH value and "jump point" of DO was observed.The SBR short-cut nitrification can be controlled at the end of nitrosation reaction by the changes of the pH,DO online, to achieve short-cut nitrification.(3)The temperature has a greater impact on the short-cut nitrification.Compared to 20℃ -25℃,the ammonia removal and nitrite accumulation rates at 30℃-35℃were relatively high, and the reaction time was significantly shortened. But when the temperature reaches 35℃,the effluent was poor and the systerm stability was disincreased. When it is 30℃,the ammonia removal rate and nitrite production rate got a high level, so as the 35℃.The sludge had well-settling and effluent quality was well and stability; 30℃was the suitable temperature of SBR reactor short-cut nitrification.(4) With the increasing of ammonia nitrogen concentration, the reaction time would lengthen, and ammonia nitrogen removal rate can be maintained at a higher level,but there was a descent of the ammonia nitrogen removal rate. Increasing synthetic ammonia nitrogen wastewater oppropriately could enhance the biomass of AOB in system, and enchanced the production of nitrite nitrogen and the rate of nitrite accumulation. However, high influent ammonia concentration will lead to FA on the inhibition of nitrification bacteria and reduce the reaction efficiency.(5) By analyzing the kinetic of short-cut nitrification in Ammonia degradation of short-cut nitrification stage, the kinetic equation is derived correspondingly, and the dynamic equation and parameters can be derived through the analysis and verification of experimental data, and the simplified equation of Arrhenius law by the influence of temperature on reaction rate:vmax(T)=0.0174x1.062(T-0)...