Cyclic activated sludge technology-recent operatin

Cyclic activated sludge technology-recent operating experienceCYCLICACTIVATEDSLUDGETECHNOLOGY-RECENTOPERATINGEXPERIENCEWITHA90.000PEPLANTINGERMANYGunnarDemoulin*,AndreasRüdiger**,MervynC.Goronszy****SFCUmwelttechnik,JuliusWelserStr.15,A-5020Salzburg**AQUABIOTECGmbH,Maria-Goeppert-Straße1,D-23562Lübeck***TriTechInc.,P.O.Box189,LakeForest,CA92630,USAABSTRACTCyclicactivatedsludgetechnologywasselectedforthePotsdamWastewaterTreatmentPlant(90,000p.e.).Thecyclicactivatedsludgefacilitycomprisesfourmodulesintegratedintotwocircularbasins.ConstructionwascommencedinFebruary1998withseedingoftheplantforstartuptakingplaceinOctober1998.ProcessperformancehasbeenmetsinceSpring1999at80-90percentofdesignload.Inordertooptimizestart-upprocedures,respirationrateswereusedasaguidanceforprocessstabilizationandonlineprocessoptimizationduringnormaloperation.Operationforco-currentnitrificationdenitirificationprovidedanammoniaremovalof1.1mgNH4-N/gMLSS.h(150C)andacorrespondingnitraterespirationrateof0.85mgNO3-N/gMLS