9周期的光暗下微藻对废水的处理效果

9周期的光暗下微藻对废水的处理效果Biotechnol.BioprocessEng.2001,6:194-199�EffectofLight/darkCyclesonWastewaterTreatmentsbyMicroalgaeKwangyongLeeandChoul-GyunLee*InstituteofIndustrialBiotechnology,DepartmentofBiologicalEngineering,InhaUniversity,Incheon402-751,KoreaAbstractChlorellakessleriwascultivatedinartificialwastewaterusingdiurnalilluminationof12hlight/12hdark(L/D)cycles.Theinoculumdensitywas105cells/mLandtheirradi-anceinlightcyclewas45µmolm2s-1attheculturesurface.Asacontrolculture,anothersetofflaskswascultivatedundercontinuousillumination.Regardlessoftheilluminationscheme,thetotalorganiccarbon(TOC)andchemicaloxygendemand(COD)wasreducedbelow20%oftheinitialconcentrationwithinaday.However,cellconcentrationundertheL/Dlightingschemewaslowerthanthatunderthecontinuousilluminatingscheme.ThusthespecificremovalrateoforganiccarbonunderL/Dcycleswashigherthanthatundercon-tinuousillumination.ThisresultsuggestedthatC.kesslerigrewchemoorganotrophicallyinthedarkperiods.Af-ter3days,nitratewasreducedto136.5and154.1