Research On Nitrogen Removal Performance And Microbial Community Of Nitrosation-Anammox Process Treating Domestic Sewage

The discovery of Nitrosation and Anammox(Anaerobic ammonia oxidation)combinedprocess made it possible to achieve efficient and low consumption nitrogen removal.Because anammox bacteria was Autotrophic denitrifier,which could use the ammonium as electron donor and the nitrite as electron acceptor,directly convert ammonium and nitrite to nitrogen gas without origanic carbon source.The most existing studies about Nitrosation and Anammox were focused on ammonium rich—wastewater,and the reports on treatment of domestic sewage via nitrosation and Anammox were relatively few.In order to promote the application of the Nitrosation-Anammox combined process in the domestic sewage treatment,SBR and ASBBR of Non-woven fabric membrane module were proposed in this study.The appropriate strategy to start the nitrification SBR and anaerobic ammonia oxidation ASBBR reactor were investigated.The changeof micorobial community structure and functional microbes in the reactor were analyzed.Then,the technical feasibility of Nitrosation SBR-Anaerobic Ammonia Oxidation ASBBR from the sewage was investigated.The denitrification performance and micorobial community were studied whenadded flocculant were discussed.The major conclusions were as follows:Conventional activated sludge taken from the second pond sludge of ShenYang northern sewage treatment plant activated sludge system.Keeped the pH in 7.6-8.3,temperature at 30-33 ?,DO ? 0.5mg/L,partial nitrifyingexperiments were carried outbasing on sequencing batch reactor(SBR),after 33days,and then nitrate nitrogen accumulation rate was gained 91.32%.High-throughput sequencing results suggested theAmmonia oxidizing bacteria(AOB)weredomesticated in SBR.The relative proportions of Nirosomonaswere accounted for14.61%.Experiments of ANAMMOX were seeded with UASB Anammox which stored at low temperature,Keeped the pH in 7.5?7.8,temperature at 30?,DO concentration?0.3?0.5mg/L and 60rmp.Used improve the ammonia nitrogen load way of enrich Anammox,Anammox process were successfully started after 91 days,HRT=6,the nitrogen removal rates of NH4+-N and NO2--N were reached 90%,and the removal rates of TN were reached 84.35%.Then the Anammox were plam red granular.High-throughput sequencing results suggestedAnammoxweredomesticated in ASBBR.The relative proportions ofCandidatus—Kuenenia,Candidatus_Jettenia,CandidatusBrocadiadengwereaccountedfor 19.46%.Based on previous independent SBR and ASBBR,through the way of gradually improved the proportion of real sewage.Keepedtemperature 33?,pH 7.8,DO?0.5 mg/L of SBR and temperature33?,pH7.5,DO ? 0.5mg/L of ASBBR.Nitrosation-Anammox experiments were developed for real sweage treatment.After 160days,SBR HRT=6h,ASBBR HRT=3,When theeffluent NH4+-N and N02--N of SBR were stable,The averageconcentration of NH4+-N in the inlet to SBR were 48.68mg/L,and the averageconcentration of NH4+-N in the outlet from ASBBR were 1.95mg/L,(averageNO2--N,NO3--N were 1.59mg/L,4.24mg/L).Average TN was7.78mg/L.The maximum removal efficiency of nitrogen was 84.59%.Based on the lost of effluent,experiments were carried out inbatch reactor.Two different kinds of flocculant were added to anammox.After MBFA9 was added,the average removal efficiency of ammonia and nitrate were 8maximum 8.13%and 85.4%.However,whenPolyaluminiumchloride was added,the removal efficiencyof Ammonia and nitrogen were just39.64%and 32.89%.Settleability of anaerobic ammonia oxidation sludgewhich added flocculants were higher than the control group,the flocculation effect in clumps.High-throughput sequencing results suggested that,compared withcontrol group,impact of adding MBFA9 to sludge was unobvious,but the impact of addingPolyaluminium chlorideto sludge was huge:Planctomycetescompletely disappeared.Adding Biological flocculating agent MBFA9 could enhance the precipitation effect of sludgeand denitrification.