influence of high organic loading on COD removal a

influence of high organic loading on COD removal and sludge production in moving bed biofilm reactor--------ENVIRONMENTALENGINEERINGSCIENCEVolume25,Number9,2008©MaryAnnLiebert,Inc.DOI:10.1089/ees.2007.0071InfluenceofHighOrganicLoadingRatesonCODRemovalandSludgeProductioninMovingBedBiofilmReactorAhmetAygun,BilgehanNas,AliBerktay*DepartmentofEnvironmentalEngineeringSelcukUniversity,Campus42031Konya,TurkeyReceived:March15,2007Acceptedinrevisedform:June16,2007AbstractAmovingbedbiofilmreactor(MBBR),wherebiomassisattachedtosmallcarrierelementsthatmovefreelyalongwiththewaterinthereactor,hasbeentestedfororganicmatterremovalatfivedifferentorganicload-ingrates.Alab-scalereactorwithavolumeof2Lwasbuiltandfedcontinuouslywithsyntheticwastewater.ThereactorwasfilledwiththeKaldnesbiomediaK1whichisusedinthepatentedKaldnesMovingBedTMbiofilmprocessat50%ofthevolumeofemptyreactor.Hydraulicretentiontimes(HRT)inthereactorandinthesettlerwereadjustedtobetween8and4hours,respectively.Astart-upperiodofabout4weeksfo