Screening and enrichment of denitrifying phosphorus accumulating bacteria using nitrite as electronic acceptor
利用亚硝酸盐为电子受体反硝化聚磷菌的筛选与富集

In this paper,according as the denitrifying phosphorus bacteria(DPB) principle,dynamic SBR reactor and static releasing/accumulating phosphorus installation were investigated.The anoxic sludge of A2/O technology was used as inoculum.The screening and enrichment of denitrifying phosphorus accumulating bacteria(DPB) using nitrite as electronic acceptor and its characteristics were studied.The result shows: the DPB using nitrite as electronic acceptor indeed lies in the anoxic sludge of A2/O technology.After anaerobic/aerobic and anaerobic/anoxic stages,the amount of PAO increases from 1400 to 32 000.The ratio of DPB to PAO improves from 14.5% to 81%.The removal rates of phosphate and nitrite rise from 8.65% and 7.55% to 91% and 95.62% respectively;when the DPB using nitrite as electronic acceptor is screened and enriched,the COD concentration of influent in the anoxic stage must be controlled below 10 mg/L.The existence of DPB is not restrained and the system is not disturbed when the system is stable and the nitrite concentration reaches as high as 30 mg/L.At the same time the concentration of phosphate in the effluent is below 1.06 mg/L.