PilotscaletertiaryMBBRnitrificationat1Ccha

FullTerms&Conditionsofaccessandusecanbefoundat=tent20EnvironmentalTechnologyISSN:0959-3330(Print)1479-487X(Online)Journalhomepage:°C:characterizationofammoniaremovalrate,solidssettleabilityandbiofilmcharacteristicsBradleyYoung,RobertDelatolla,BaishaRen,KevinKennedy,EdithLaflamme&AlainStintziTocitethisarticle:BradleyYoung,RobertDelatolla,BaishaRen,KevinKennedy,EdithLaflamme&AlainStintzi(2016)Pilot-scaletertiaryMBBRnitrificationat1°C:characterizationofammoniaremovalrate,solidssettleabilityandbiofilmcharacteristics,EnvironmentalTechnology,37:16,2124-2132,DOI:10.1080/09593330.2016.1143037Tolinktothisarticle::20Jan2016.Publishedonline:22Feb2016.SubmityourarticletothisjournalArticleviews:197ViewrelatedarticlesViewCrossmarkdataCitingarticles:3ViewcitingarticlesPilot-scaletertiaryMBBRnitrificationat1°C:characterizationofammoniaremovalrate,solidssettleabilityandbiofilmcharacteristicsBradleyYounga,RobertDelatollaa,BaishaRena,KevinKennedya,EdithLaflammebandAlainStintzicaDepartmentofCivilEngineering,UniversityofOttawa,Ottawa,ON,Canada;bVeoliaWaterTechnologiesCanadaInc.,Montreal,QC,Canada;cDepartmentofBiochemistry,MicrobiologyandImmunology,OttawaInstituteofSystemsBiology,FacultyofMedicine,UniversityofOttawa,Ottawa,ON,CanadaABSTRACTPilot-scalemovingbedbiofilmreactor(MBBR)isusedtoinvestigatethekineticsandbiofilmresponseofmunicipal,tertiarynitrificationat1°C.TheresearchdemonstratesthatsignificantratesoftertiaryMBBRnitrificationareattainableandstableforextendedperiodsofoperationat1°C,withamaximumremovalrateof230gN/m3dat1°C.Atconventionalnitrogenloadingrates,lowammoniaeffluentconcentrationsbelow5mg-N/Lwereachievedat1°C.Thebiofilmthicknessanddryweightbiofilmmass(massdw)wereshowntobestable,withthicknessvaluesshowingacorrelationtotheprotein/polysaccharideratioofthebiofilmextracellularpolymericsubstances.Lastly,tertiaryMBBRnitrificationisshowntoincreasetheeffluentsuspendedsolidsconcentrationsbyapproximately3mgtotalsuspendedsolids/L,with19–60%ofeffluentsolidsbeingremovedafter30minofsettling.ThesettleabilityoftheeffluentsolidswasshowntobecorrelatedtothenitrogenloadingoftheMBBRsystem.ARTICLEHISTORYReceived15July2015Accepted12January2016KEYWORDSMBBRtertiarynitrification;coldtemperature;biofilmmorphology;protein/polysaccharideratio;solidsanalysis1.IntroductionPointsourcepolluters,suchaswastewatertreatmentplants,areaddinglargequantitiesofnutrientstosurfacewaters.[1]Increasingthenutrientconcen-trationsinsurfacewaterscancauseeutrophicationandvariousotherundesirableecologicalimpacts.Specifically,unionizedammoniaistoxictofishandotheraquaticorganisms.Inanattempttomitigatepol-lutionfromwastewaters,variouscountriesaredevelop-ingmorestringentwastewatereffluentregulations.[2–4]Currenttreatmenttechnologieshaveshowntobeeffectiveinremovingcarbonaceousbiochemicaloxygendemand(CBOD)andtotalsuspendedsolids(TSS);however,thesetechnologiesareoftenlimitedwithrespecttonitrificationoncetemperaturesdecreasebelow10°C.[5–7]Passivetreatmentsystems,suchasmulti-pondlagoons,arecommoninnorthernclimateswherelandisreadilyavailable.Thesesystemsareabletonitrifyinthesummermonthsduetotheirlongsolidsretentiontime(SRT).Inthewintermonths,wastewatertempera-turescanreachaslowas1°Cforextendedperiodsofoperation.[3]Atthistemperature,passivetreatmentsystemsareincapableofnitrificationandassuchtherehasbeenanincreasedinterestinadd-onnitrifyingbiofilmtechnologies.Biofilmshaveshownthepotentialtodecreasethetemperaturesensitivityoftheembeddednitrifiers.[8]Recently,themovingbedbiofilmreactor(MBBR)hasdemonstratedthepotentialforcoldtemperaturenitrifi-cation.[9–14]TheMBBRsystemhousesbio-carriers,whichremaininconstantmovementintheMBBRduringoperation.Themovementofthecarrierelimin-atestheneedforbackwashingofthesystem.Thecom-binedefficiencyandsimpleoperationoftheMBBRmakeitidealasapotentialupgradetechnologyforpassivetreatmentsystems.[15]ThefirststudieswithrespecttoMBBRnitrificationincoldwastewaterswereperformedonMBBRupgradesystemsinstalledatmulti-pondlagoontreatmentfacili-ties.ThesestudiesinvestigatedupgradeMBBRnitrifica-tionsystemsinstalledafterthefirstormiddlepondofamulti-lagoontreatmentsystemtominimizethetemp-eraturedecreaseofthewastewaterthroughthetreat-mentprocesspriortoenteringthenitrifyingMBBRsystem.[10,13,14]Thewastewatertemperaturesafterthefirstormiddlepondofmulti-lagoonfacilitiesinnorthernclimateswereobservedtoreachtemperaturesaslowas4°Casopposedto1°C,henceprovidinghigherminimumtemperaturestoachievenitrificationintheMBBRsystems.Althoughtheminimumtemperatureofwastewaterfromthefirstormiddlepondofpassive©2016Taylor&[e-mail]Y,2016VOL.37,NO.16,2124–2132five-dayCBOD(CBOD5)tototalKjeldahlnitrogen(TKN)ratio,whicheffectsthecompetitionbetweenfastergrowingheterotrophicands