An Investigation of Moving Bed Biofilm Reactor Nit

An Investigation of Moving Bed Biofilm Reactor Nitrification during Long-Term Exposure to Cold TemperaturesAnInvestigationofMovingBedBiofilmReactorNitrificationduringLong-TermExposuretoColdTemperaturesValerieHoang1,RobertDelatolla1*,EdithLaflamme2,AlainGadbois2ABSTRACT:Biologicaltreatmentisthemostcommonandeconomicalmeansofammoniaremovalinwastewater;however,nitrificationratescanbecomecompletelyimpededatcoldtemperatures.Attachedgrowthprocessesand,specifically,movingbedbiofilmreactors(MBBRs)haveshownpromisewithrespecttolow-temperaturenitrification.Inthisstudy,twolaboratoryMBBRswereusedtoinvestigateMBBRnitrificationratesat20,5,and18C.Furthermore,thesolidsdetachedbytheMBBRreactorswereinvestigatedandArrheniustemperaturecorrectionmodelsusedtopredictnitrificationratesafterlong-termlow-temperatureexposurewasevaluated.Thenitrificationrateat58Cwas6663.9%and6463.7%comparedtotheratemeasuredat208Cforreactors1and2,respectively.Thenitrificationratesat18Covera4-monthexposureperiodcomparedtotherateat208