Determining The Operational Conditions Of Modified SBR For Enhanced Biological Nitrogen And Phosphorus Removal From Campus Sewage

Along with China’s growing water pollution, eutrophication problems have becomeincreasingly prominent, a single purpose of remove organic matter for the traditionalwastewater treatment technology was gradually developed to the advanced treatmenttechnologies which necessary to remove organic matter and nitrogen and phosphorusremoval, in order to control eutrophication enhanced biological nitrogen andphosphorus removal technology has become one of the focus of the field for sewagetreatment.On the basis of analysis of the campus sewage water quality characteristics, thisexperiment researched into the water quality impact on biological nitrogen andphosphorus removal, used two ways (improved step feed UCT-SBR andpre-denitrification AO-SBR) to run the enhanced biological phosphorus and nitrogenremoval SBR Process to treat the campus sewage water, designed to improve thenitrogen and phosphorus removal efficiency of the conventional SBR ProcessTreatment of Low Concentration campus effluent, realize organic matter, nitrogen,phosphorus and other pollutants meeting the discharge standards at the same time, andsimulates the actual treatment to the campus sewage systems, recovery experiment ofthe activated sludge was done to the modified SBR process at the idle after shut down，acomparative study were proposed to the recovery characteristics of the process.Through experiments and theoretical analysis, the following test results were obtained:（1）Throughout monitoring of the whole process of the campus sewage inflow we can see big campus sanitary sewage quality fluctuations, the campus sanitary sewagequality and quantity decreased sharply during the summer; influent COD concentrationand C/N value affected the nitrogen and phosphorus removal effect of the UCT-SBRprocess, with the influent TCOD concentration increased the nitrogen and phosphorusremoval efficiency were increased too, the effect of C/N ratio to the nitrogen andphosphorus removal performance can fully reflect the impact of water quality on thebiological nitrogen and phosphorus removal.（2）According to the four kinds of water proportion setted by Step-FeedUCT-SBR,the test process classified as four conditions, with AO-SBR process alwaysadopt constant operation mode, four kinds of working conditions, two process areshowing high removal rate of COD,the average removal rate is over85%, withsignificantly indifference; the denitrification efficiency using UCT-SBR process isalways superior to the AO-SBR process; with the affect of inlet water quality andoperating conditions, the phosphorus removal rate of UCT and SBR is not stable.（3）In the second operating condition (using UCT-SBR process with water ratio of1:1:2), the denitrification rate of the two process were74.34%and58.27%respectively,both show high phosphorus removal rate, and the former show nearly9%higher thanthe latter, therefore, the second operating condition was the best operatingcondition,without affeceting the COD removal efficiency, UCT and SBR process haveshown a higher removal rate than AO-SBR process in nitrogen and phosphorus.（4） Under the condition of high temperature, after a stage of "hunger",which aslong as42d, the activated sludge in SBR process can restore its ability to removeorganic pollutants, during4-8recovery cycles. Under the same condition of inflowwater quality and operating condition the two process have the similar recoverycharacteristics, the speed of recovery is also similar, but when treating actual campussewage with low concentration under a stable condition,the Step-Feed UCT-SBRprocess have a great advantages over the front-facing anoxic denitrification AO-SBR indenitrification.