Effect of retention time in fixed-bed reactors for the treatment of effluents in rainbow trout (Oncorhynchus mykiss) culture

摘要

Themainobjectiveofthisresearchwastoevaluatetheefficiencyofupflowbiofilterswithfixedfilmtotallysubmergedbycomparisonoftwodifferenthydraulicretentiontimesforwastewatertreatmentofrainbowtroutcultureinarecirculatingsystem.Thetreatmentsconsistedinhydraulicretentiontimesof15to20min(T15-20)andnbsp;20to25min(T20-25).Afteraperiodofmaturationofthebiofilters,rainbowtroutnbsp;ataloadof6.4kg/m3wereculturedduringsixweeks.Twiceaweeksamplesweretakenforanalysisofchemicaloxygendemand(COD),totalammonianitrogen(TAN),nitrite(NO2-),nitrate(NO3),phosphate(PO4-3),totalsolids(TS),volatilesolids(VS)andtotalfixedsolids(TFS).Temperature,oxygen,pHandalkalinityweremeasured;fishbiomasswasdeterminedeveryfifteendays.ItwasconcludedthattreatmentT20-25wasmoreefficientforNO3removal.TherewasatendencyforTSandVSremovaltobebetterwithT15-20.Productionparametersweremaintainedwithintherecommendedrangesfortroutculture.Thegrowthrateofthetroutwas1.5g/dandthefeedconversion1.4.