Zhang Yu-Jun, Li Dong, Wang Xin-Xin, Zhang Jie
Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Faculty of Architecture, Civil and Transportation Engineering, Beijing University of Technology, Beijing 100124, China.
State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
Huan Jing Ke Xue. 2021 Sep 8;42(9):4383-4389. doi: 10.13227/j.hjkx.202101190.
This study explored the effect of sludge retention time (SRT) on ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) under intermittent gradient aeration, as well as the effect of the short-range nitrification endogenous denitrification phosphorus removal system on the treatment of low C/N ratio domestic sewage. In this study, an SBR reactor was used to cultivate aerobic granular sludge, using actual domestic sewage as the influent substrate. As the SRT decreased from 50 d to 30 d, the specific ammonia oxidation rate increased from 3.16 mg·(g·h)to 4.38 mg·(g·h), and the specific nitrite oxidation rate decreased from 3.4 mg·(g·h)to 1.8 mg·(g·h). The activity of NOB decreased by about 44%, resulting in short-range nitrification within the system. With an SRT of 30 d, the maximum nitrite accumulation was 6.93 mg·L. Because the reduced SRT led to a slight decrease in sludge concentration within the system, an aeration reduction strategy was adopted after 40 d, according to the DO curve. When the final SRT was 30 d, the effluent COD concentration was 40.76 mg·L, the TN concentration was 12.4 mg·L, the TP concentration was 0.31 mg·L, and the simultaneous removal of C, N and P was realized. Thus, a stable short-range nitrification endogenous denitrification phosphorus removal system was finally obtained. At the same time, the EPS content of aerobic granular sludge was negatively correlated with SRT, the protein content increased from 66.7 mg·g to 95.1 mg·g, and the polysaccharide content remained in the range of 12.1-17.2 mg·g, indicating that the decreased SRT had a great effect on the protein content. With an SRT of 30 d, the PN/PS value was maintained at approximately 6.2, and the structural stability of aerobic granular sludge can be maintained under such conditions.
本研究探讨了间歇梯度曝气条件下污泥停留时间（SRT）对氨氧化细菌（AOB）和亚硝酸盐氧化细菌（NOB）的影响，以及短程硝化内源反硝化除磷系统对低C/N比生活污水的处理效果。本研究采用SBR反应器培养好氧颗粒污泥，以实际生活污水作为进水底物。随着SRT从50 d降至30 d，氨氧化比速率从3.16 mg·(g·h)增至4.38 mg·(g·h)，亚硝酸盐氧化比速率从3.4 mg·(g·h)降至1.8 mg·(g·h)。NOB活性下降约44%，导致系统内实现短程硝化。SRT为30 d时，最大亚硝酸盐积累量为6.93 mg·L。由于SRT降低导致系统内污泥浓度略有下降，根据溶解氧曲线，在40 d后采用了曝气减量策略。当最终SRT为30 d时，出水COD浓度为40.76 mg·L，TN浓度为12.4 mg·L，TP浓度为0.31 mg·L，实现了C、N和P的同步去除。最终获得了稳定的短程硝化内源反硝化除磷系统。同时，好氧颗粒污泥的胞外聚合物（EPS）含量与SRT呈负相关，蛋白质含量从66.7 mg·g增至95.1 mg·g，多糖含量保持在12.1 - 17.2 mg·g范围内，表明SRT降低对蛋白质含量影响较大。SRT为30 d时，PN/PS值维持在约6.2，在此条件下可维持好氧颗粒污泥的结构稳定性。
