Study On Simultaneous Nitrification And Denitrification And Phosphorus Removal In Single Tank Of Newly Oxidation Ditch System

The problem of environment is a focus in the modern society ,it impacts people's social life comprehensive and profound . Environmental deterioration is now the key factor lead to disease and death, among the environmental problems water body pollution and water resources will be the most serious problems for a long time. Water body eutrophication is one of the aftermath of water pollution,so under the condition of China,it's necessary to search a simple but high efficiency waste water treatment craft Researches indicated that simultaneous nitrification and denitrification (SND) occur in the outside ditch of Orbal oxidation ditch , SND can can reduce the number and size of the reaction equipments, decrease the oxygen supply amount then save energy, and save expenditures for dosages, etc,but there are some shortcomings. On the base of tradition Orbal oxidation ditch, the model of this experiment is a new single oxidation ditch through the modify of ditch type,solid-liquid separator and backflow ways, etc. To remove COD,SS,N and P(simultaneous biological nutrition removal ,shorted as SBNR) simultaneity by rationally allotment of time and space in this system.In the experiments of new single oxidation ditch model, main research has been emphasized on the effects of some operational parameters, such as DO(average dissolved oxygen of out side ditch),SRT,HRT,r, F/M, C/N, HRT and SRT, on its operational performance.Choose three level of each parameter, to make 9 work conditions by orthorhombic method, among them the best work condition is condition 4, when: SRT=15d,HRT=12h,DO=0.4mg/L , r=0.1and each of the removal ratio under the condition are: ECODcr=87.6% ,ENH4+-N=89.7%,ETN=82.1%,ETP=76.3%.。The main parameters may provide reference for the design and operation of the similar oxidation ditch.This paper made comprehensive analysis on the nutrition removal(include COD,NH4+-N,TN,TP) and each parameter's affection (HRT,SRT,DO,r), the maximal parameter to denitrification is SRT and to SND in outside ditch is DO. Then the bio-dynamical analysis has been made with the experimental results in the new single oxidation ditch system, the maximum specific velocity of substrate removal Vmax = 4.75d-1, and the organic contaminant degradation coefficient Ks = 75.81mgCOD/d; the reaction order in of NH4+-N degradation n=0, and the reaction velocity constant k=2.07. Finally, energy save analysis has been done to the model, the new ditch save 30%...