Study On Pollutant Removal Effect Of Sidestream SBR Biological Phosphorus Removal Process

With the acceleration of urbanization,the discharge of urban domestic sewage has increased year by year,and the pollution of surface water environment has become increasingly serious.Among them,phosphorus in sewage is one of the main culprits of eutrophication of surface water bodies.Therefore,improving the phosphorus removal effect of sewage plants is the key to controlling surface water pollution.However,with the reformation of the sewage treatment plant,the original sewage treatment process has poor phosphorus removal effect and large economic cost.At present,a high-efficiency and low-energy enhanced biological phosphorus removal process is urgently needed to meet the discharge requirements of the effluent phosphorus.Based on this,this study takes the SBR sirestream enhanced biological phosphorus removal process(means adding a sidestream anaerobic fermentation tank for the SBR reactor)as the research object,and explores the hydrolysis acid production rule of the anaerobic fermentation tank sludge,and optimizes the effect of pollutant removal process.,clarifies the biological characteristics of phosphorus removal in the reactor,and providing technical and theoretical support for the efficient removal and resource utilization of phosphorus.The study draws the following conclusions:(1)After the start-up phase,the reactor is operated stably,and the removal efficiency of COD,NH4+-N,and TP is 90%,68%,and 72%by SBR process.When the sidestream ratio is 20%,HRT(Hydraulic Retention Time)is 6h,and aeration 4 precipitation 2(h),the maximum SCOD,TOC and volatile organic acids(VFAs)are 280mg/L,70 mg/L and 160mg/L;the best hydrolysis and acidification effect,the highest acid production efficiency,the accumulation of carbon source;acetic acid in the VFAs accounted for 35%,propionic acid accounted for about 10%,butyric acid(isobutyric acid and N-butyric acid)and valeric acid(isovalerate and N-valeric acid)is about 35%and 20%,respectively;the concentration of branched isobutyric acid and isovaleric acid is lower than that of unbranched N-butyric acid.and N-valeric acid;(2)Using the VFAs produced in the anaerobic fermentation tank,the SBR process has improved the pollutant removal.When the sidestream ratio is 20%,HRT is 6h,and e aeration 4 precipitation 2(h),COD,NH4+-N,TN,and TP have the best removal rates of 93%,85%,73%,and 90.5%.Concentrations of 24mg/L,4.53 mg/L,6.35mg/L,0.4 mg/L;(3)The amount of anaerobic phosphorus released increased with the increase of sidestream ratio,HRT and aeration mode.When the sidestream ratio was 20%,HRT was 8h,and aeration 5 precipitation 1(h),the amount of phosphorus released reached The maximum,respectively,reached 20mg/L,26mg/L,30mg/L.When the amount of phosphorus released was the largest,the total phosphorus content in the discharge system(125.5mg)was basically equal to the total phosphorus in the system(127.4mg),indicating the amount of phosphorus achieve dynamic conservation in the system.;(4)Using SEM technology to observe the biological phase of activated sludge,it is found that the bacteria in activated sludge are mainly cockroaches,worms,cockroaches,worms and actinomycetes,microbial diversity and flora.The quantity is obviously higher than that of the original sludge,and the effect of nitrogen and phosphorus removal is good.The characteristics of EPS distribution in activated sludge are found to be the main components of tryptophan(C1),humus(C2)and protein(C3).The maximum peak fluorescence intensity of C1,C2,and C3 is the largest when the sidestream ratio is 20%,HRT is 6h,and aeration 4 precipitation 2(h)the maximum peak fluorescence intensity of C1,C2 and C3 is the highest.The maximum peak fluorescence intensity of C1 and C3 is TB-EPS>LB-EPS>SMP,and the largest peak fluorescence intensity of C2 is TB-EPS<LB-EPS<SMP,the maximum peak fluorescence intensity of C1 and C3 is higher than C2.(5)Using SEM technology,it was observed that the microbial phase on the surface of the sludge was diversified,and the species were abundant,mainly cocci and bacillus,and a small amount of bacillus and filamentous bacteria were grown.Using high-throughput sequencing,it was found that the microbial microbial flora in the sidestream SBR process were mainly Proteobacteria,Actinobacteria,Alphaproteobacteria,Betaproteobacteriales,Gammaproteobacteria and RHodocyclaceae,and Proteobacteria accounted for 52.6%,belonging to the dominant polyphosphate flora;Gammaproteobacteria The proportion is 41.9%-50.20%,which is also the dominant flora;RHodocyclaceae belongs to polyphosphate bacteria,accounting for 21.8%-28.6%;and HRT is the best ratio at aeration 4 precipitation 2(h),and the number of polyphosphate microbial flora is the highest.