定向调控电子受体强化好氧颗粒污泥内源反硝化脱氮除磷

Enhance nitrogen and phosphorus removal via endogenous denitrification of aerobic granular sludge by directional regulation of electron acceptor

为强化内源反硝化作用,加强对有限碳源的高效利用,设置了1组厌氧/好氧/缺氧(A/O/A)和3组不同好氧时间分配的厌氧-两级短时好氧/缺氧(A/(O/A)_(2))序批式反应器,探究定向调控电子受体下污泥的颗粒化及反硝化聚糖菌(DGAOs)的富集情况.结果表明,采用两级短时好氧/缺氧的反应器好氧颗粒污泥结构更加致密、沉淀性能更好,缺氧段及好氧段电子受体更充足,DGAOs储存内碳源的能力得以强化,系统中反硝化聚糖菌和DGAOs对碳源的竞争达到平衡状态,系统有更高的内源反硝化脱氮率,实现了深度脱氮除磷.其中,两级短时好氧时间分配时间为前段60min/后段30min的R2的脱氮除磷效果最好,DGAOs含量最高,且颗粒沉降性能最佳.第45d,R2的COD、TN、TP去除率分别达到90.52%、85.71%、92.73%,内源反硝化效率达到58.59%,具有良好的污染物去除效果.

In order to strengthen endogenous denitrification and enhance the efficient utilization of limited carbon sources,in this study,one anaerobic/aerobic/anoxic(A/O/A)sequencing batch reactor and three groups of anaerobic/two-stage short-time aerobic/anoxic(A/(O/A)_(2))sequencing batch reactors with different aerobic time allocations were implemented to assess sludge granularity and the enrichment of denitrifying glycogen accumulating organisms(DGAOs)across directional regulation of electron acceptor.The findings indicated that the aerobic granular sludge in the two-stage short-time aerobic/anoxic reactor exhibited a more compact structure,superior sedimentation performance,increased availability of electron acceptors in both anoxic and aerobic phases.Furthermore,the capability of DGAOs to accumulate endogenous carbon sources was enhanced.The competition between denitrifying polyphosphate accumulating organisms(DPAOs)and DGAOs for carbon sources reached an equilibrium state within the system.Consequently,the system demonstrated heightened endogenous denitrification and nitrogen removal rates,thereby achieving profound nitrogen and phosphorus removal.Notably,among these reactors,R2,featuring a two-stage short aerobic time allocation of 60minutes in the initial segment and 30minutes in the subsequent segment,exhibited optimal denitrification and phosphorus removal efficacy.This reactor displayed the highest content of DGAOs and superior particle settling performance.During the stable operational phase,R2achieved removal rates of 90.52%,85.71%,and 92.73%for COD,TN,and TP,respectively.Additionally,the endogenous denitrification efficiency reached 58.59%,underscoring its commendable pollutant removal capabilities.