中文摘要：

以乙酸钠和丙酸钠1：2混合作为碳源，进水COD浓度分别为200，400，600，800mg／L，研究混合碳源浓度对单级好氧生物脱氮除磷的影响，并通过比较微生物体内储能物质的变化，探讨混合碳源浓度对生物脱氮除磷性能影响的机理.结果表明，当进水磷和氨氮浓度分别为12，30mg／L时，随着进水COD由200增加至800mg／L，磷去除率由39.9％提升至86.4％（氮去除率从13.5％提升至96.4％）.进水COD为400mg／L时单位挥发性悬浮固体（Vss）的磷和氮去除量达到最高[分别为（4.31±0.08）和（6.15±0.22）mg／g].当进水COD由200增加至400mg／L时生物除磷活性增强，而COD继续增加会使污泥沉降性能变差，脱氮除磷生物活性降低好氧吸磷和同步硝化反硝化主要由微生物体内储能物质多B羟基烷酸盐（PHA）驱动，当进水COD为400mg／L时单位VSS消耗的PHA最多.混合碳源浓度通过影响碳源的好氧代谢，使微生物体内储能物质的积累，转化量不同，进而影响系统的脱氮除磷性能.

英文摘要：

To study the effect of mixed carbon source concentration on nitrogen （N） and phosphorus （P） removal in the oxic/extended-idle process, four sequencing batch reactors were operated using sodium acetate and sodium propionate with 1：2 hybrid configured influent COD concentrations of 200, 400, 600 and 800mg/L respectively. The variations of intracellular polymers and the metabolic mechanism were investigated. The experimental results showed that with influent P and N concentrations of 12 and 30mg/L respectively, P and total nitrogen （TN） removal efficiencies were respectively promoted from 39.9% and 54.5% to 86.4% and 98.0% with the increase of influent COD from 200 to 800mg/L. The highest N, P removal per unit VSS [（4.314-0.08） and （6.15~-0.22）mg/g] were both detected under influent COD of 400mg/L. P accumulating activity was enhanced when COD rose from 200 to 400mg/L, but the further increase of influent COD would result in deterioration of sludge settling, leading to a compromised biological N and P removal activity. Both aerobic phosphorus uptake and simultaneous nitrification and denitrification were driven by poly-β-hydoxyalkanoate （PHA）, and the largest amount of PHA consumption per unit VSS was observed under influent COD of 400mg/L. The mixed carbon source concentration influenced microbial aerobic metabolism, which resulted in the difference of the accumulation/conversion of intracellular polymers, and thus influenced N and P removal performance.