Practical Application And Studies Of Orbal Oxidation Ditch In The Municipal Wastewater Treatment Plant

The determination of the influent wastewater quantity is one of the most important Parameters of the Wastewater Treatment Plants in design,generally speaking,it is difficult for the designed influent wastewater quantity to be the same with the actual, because there are many influences on influent wastewater quantity.As a result,the actual influent wastewater quantity can not reach the designed scale or the structure in design is too small to meet the actual quantity.Through the investigation and analysis of actual influent quantity in the No.3 Wastewater Treatment Plant of Xi'an City for about one year,this paper proposed the way how to determine designed influent quantity by changeable coefficient;and analysed physical handling capacity of grid and Aeration tank.And thus to determine the garbage quantity in each cubic meter wastewater.Through an investigation of water quality parameters at the main tanks in the No.3 Wastewater Treatment Plant of Xi'an City,the results indicate that the fast absorption and degradation of pollutants in the selector,and the efficiency of COD,TN and NH₃-N removal is 78.95%,54.65%and 45.73%;This progress has strong anti-impact load ability,so water quality is more stable.The total efficiency of COD,TN,NH₃-N and TP removal can reach 94.03%,68.20%,91.06%and 96.18%.In addition,batch experiments are also conducted to determine the oxygen uptake rate,the ammonium uptake rate,and the denitrification rate.It shows that a larger open degree of the Aerational Switch plate results in the high dissolved oxygen of the outside ditch,so the denitrification rate is very low.Although the total efficiency of TN is not high,the effect of NH₃-N still keeps good.Through statistics and analysis about the measured results in the running process of the No.3 Wastewater Treatment Plant of Xi'an City,it is believed that SVI suitably stays between 100 and 150 in design or running Wastewater Treatment Plants,and this paper advances that process operators may use SVI to guide the running,besides,it generalizes the relationship of SVI between N_S and SS in outfluent wastewater.