厌氧/好氧SNEDPR系统处理低C/N污水的优化运行

为实现同步硝化内源反硝化除磷（SNEDPR）系统的优化运行，以实际生活污水为处理对象，采用厌氧（180min）/好氧运行的SBR反应器，并通过联合调控好氧段溶解氧（DO）浓度（0.3～1.0mg/L）和好氧时间（150～240min），考察了该系统脱氮除磷特性.并结合荧光原位杂交（FISH）技术对系统优化过程中各功能菌群的结构变化情况进行了分析.试验结果表明，当系统好氧段DO浓度由约1.0mg/L逐渐降至0.3mg/L，且好氧时间由150min逐渐延长至240min后，出水PO₄^3--P浓度稳定在0.4mg/L左右，但出水TN浓度由14.3mg/L降至8.7mg/L，TN去除率由75%提高至84%.此外，随着好氧段DO浓度的降低，SNED现象愈加明显，SNED率由34.7%逐渐升高至63.8%.SNED的加强，降低了出水NO₃^--N浓度，并提高了系统的脱氮性能和厌氧段的内碳源储存量.FISH结果表明：经127d的优化运行，系统内PAOs，GAOs和AOB（氨氧化菌）仍保持在较高水平（分别全菌的29%±3%，20%±3%和13%±3%），其保证了系统除磷、硝化和反硝化脱氮性能；但NOB（亚硝酸盐氧化菌）含量减少了50%，为系统内实现短程硝化内源反硝化提供了可能.

Optimization for low C/N sewage treatment in an anaerobic/aerobic simultaneous nitrification-endogenous denitrification and phosphorous removal system

This study focused on the nitrogen (N) and phosphorus (P) removal performance optimization in simultaneous nitrification-endogenous denitrification and phosphorus removal (SNEDPR) systems. An anaerobic (180min)/aerobic sequencing batch reactor (SBR) fed with domestic wastewater was studied for optimization of N and P removal performance of SNEDPR by regulating the aerobic dissolved oxygen (DO) concentration (0.3~1.0mg/L) and aerobic duration time (150~240min). FISH technology was also employed to analyze the population dynamics of functional microorganisms in the SNEDPR system. Results indicated that the effluent PO₄^3--P concentration was below 0.4mg/L, effluent TN concentration decreased from 14.3mg/L to 8.7mg/L, and TN removal efficiency increased from 75% to 84% with aerobic DO concentration decreased from 1.0mg/L to 0.3mg/L and aerobic duration time increased from 150min to 240min. SNED was enhanced by the decreased aerobic DO concentration, with SNED efficiency increased from 34.7% to 63.8%. The enhanced SNED reduced the effluent NO₃^--N concentration, improved the N removal performance, and strengthened the intracellular carbon storage at the following anaerobic stage. FISH results showed that the populations of PAOs, GAO and AOB (ammonia oxidizing bacteria) still maintained at high levels in the 127-day optimized SNEDPR-SBR (accounting for 29%±3%, 20%±3% and 13%±3% of total biomass, respectively), which ensured the P uptake, nitrification and denitrification; however, NOB (nitrite oxidizing bacteria) reduced by 50%, which provided a possibility to achieve N removal through simultaneous partial nitrification-endogenous denitrification in the SNEDPR.