Influencing Factors And Model Prediction Of DO In The Process Of Sanitary Sewage

Starting from the current situation of our country’s sewage processing, this paperbriefly introduces A2/O biological denitrification and phosphorus removalprocess.When regard the third sewage treatment plant in Xining as a research object,which use the A2/O biological denitrification and phosphorus removal technology,then combine with the pilot test in wastewater treatment plant in Yushu, to have along-term analysis and monitor to those parameters in the process of A2/O sewagetreatment, they are: chemical oxygen demand(CODcr) and biochemical oxygendemand(BOD5) as well as temperature in the Aeration reaction pool(T)、PH value、sludge index(SVI)、30minsettlingratio(SV30)、sludge concentration(MLSS)、suspendedsolid(SS) and Dissolved Oxygen(DO); Analysize inflow COD and BOD as well aseach parameter in the aeration tank on the influence of DO with the method of unarylinear regression. The result shows that all parameters have less effect on the DO,Linear correlation is poor; when study the each parameter in the Aeration reactionpool on the influence of DO in a short time by means of multiple linear regressionanalysis method, and establish mathematical model to predict and analysize, we canhave a correlation of the measured values.At the same time, using BP neural network to choose inflow CODcr、BOD5andT、SV30、SVI、pH、MLSS、SS、DO (in the aeration tank) as BP’s learning set trainingmodel. Thereinto,choosing T、SV30、SVI、pH、MLSS、SS、DO as input layer, whileDO as output to have a BP neutral network analysis, we can get a good predictiondata,which is related to DO measured value.The result shows: Within a certain range of the response to the sewagetreatment plant aeration pool DO multiple linear regression analysis and neuralnetwork simulation study has found: Multiple linear regression forecast MLRcompared to DO the correlation of the measured values, R=0.808; Simulation resultsof BP network is better,R=0.9978. This study shows that the BP neural network tothe DO of aeration reaction pond forecast is better.