Effect of Temperature on Biofilm Growth Dynamics a

Effect of Temperature on Biofilm Growth Dynamics and Nitrification Kinetics in a Full-Scale MBBR System1EffectofTemperatureonBiofilmGrowthDynamicsandNitrificationKineticsinaFull-ScaleMBBRSystemCoreyBjornberg1*,Dr.WeiLin2,Dr.RobertZimmerman31HazenandSawyer,Cincinnati,OH45242USA2NorthDakotaStateUniversity,Fargo,ND58105USA.3CityofMoorhead,MN56561USA.*cbjornberg@hazenandsawyer.comABSTRACTTheMoorhead,MinnesotaWastewaterTreatmentFacility(WWTF)operatesamovingbedbiofilmreactor(MBBR)tocomplywithseasonalammoniadischargelimitations.Sincebecomingoperationalin2003ithasshowntheabilitytoreachhighammoniaremovalefficiencyyearroundeventhoughitissubjecttotheextremetemperaturevariationsfoundintheupperMidwest.Monitoringdataforattachedbiomassrevealeddramaticchangesfromwintertosummermonthswithlargequantitiesofattachedbiomassinthecoldermonthsandsignificantlylessinthewarmermonths.Monitoringresultsindicatedthatattachedbiomass,biofilmthickness,andbiofilmmorphologychangesignificantlyfromwarmtocoldweathermonths.At