Study On The Simulated NH₄⁺-N Wastewater Treatment With Short-cut Nitrification-denitrification In SBR

Short cut nitrification denitrification technology is a new nitrogen removal process developped recent years.Compared with the traditional biological nitrogen removal process,this process has the advantages of save aeration,save denitrification carbon source,short hydraulic retention time and reduce the amount of excess sludge,thus attractted more and more attentions.This paper used SBR reator, through real time control technology,simulated NH4+-N wastewater as object, studied the feasibility of pH as the direct parameter in nitrification and denitrification, completed nitrification and denitrification of sludge acclimation, in the course of the study by changing the experimental conditions, the stability of short range nitrification was investigated.At last, dicussed the kinetic about short cut nitrification,and the kinetic model of short cut nitrification denitrification was proposed.The experimental results showed that:(1) Use SBR treated the simulated NH4+-N wastewater,the change of pH has a certain regularity in the oxidation of organic matter, nitrification and denitrification process, the curve of pH value change process has three distinct feature points, respectively corresponds to the end of the oxidation of organic matter, nitrification, denitrification reaction.Changed the organic loading,pH,NH4+-N concentration of the influent and change the amount of aeration at the Nitrification stage,the change regulation of pH was not chang.So it can use thoses characteristic points to judge the short cut nitrification denitrification.(2) On the basis of full nitrification denitrification sludge,through control the aeration rate in the nitrification stage and the higher pH of influent water, achieved short cut nitrification denitrification sludge acclimation in low DO and high pH. After acclimation,the nitrite nitrogen accumulation rate keep above 90%.(3) After the success of short range sludge acclimation, in order to investigate the stability of short range nitrification, lower the reacter temperature,increase the aeration rate and lower the influent pH, short cut nitrification was not destroyed, the nitrite nitrogen accumulation rate could still above 90%. (4) It was found that the over aeration could change the short cut nitrification to full nitrification.Changed real time control to fixed time control.On the 6th day after overaertion,accumulation of nitrite fell to 43.7%,the style of nitrification from short cut nitrification changed to full nitrification.(5)At last,this paper dicussed the kinetic about short cut nitrification denitr-ification,got the kinetic model in short cut nitrification.