DO和C/N对低温运行A^(2)/O-MBR脱氮除磷效能的影响研究  

Effect of DO and C/N on nitrogen and phosphorus removal efficiency of A^(2)/O-MBR at low temperature

作　　者：郭祥 郭新超 熊家晴 周佳佳 GUO Xiang;GUO Xinchao;XIONG Jiaqing;ZHOU Jiajia(Shaanxi Key Laboratory of Environmental Engineering,Key Laboratory of Northwest Water Resource,Environment and Ecology,MOE,Environmental and Municipal Engineering Department,Xi’an University of Architecture and Technology,Xi’an 710055,China)

机构地区：[1]西安建筑科技大学环境与市政工程学院,陕西省环境工程重点实验室,西北水资源与环境生态教育部重点实验室,西安710055

出　　处：《环境工程》2025年第1期118-124,共7页Environmental Engineering

基　　金：青海省中央引导地方科技发展资金项目(2022ZY039)。

摘　　要：高原污水处理厂受低温、低压影响,微生物活性较低,氮、磷出水指标普遍较高,能耗、药耗运行成本居高不下。选取A2/O-MBR工艺,研究在低温运行时不同DO浓度、C/N对系统脱氮除磷性能的影响。试验结果表明:反应器内水温10℃,HRT为12 h,两段混合液回流比200%时,系统MLSS为7000 mg/L,远超传统活性污泥法,一定程度上弥补了因低温造成的微生物活性不足;DO浓度在1.0~1.5 mg/L时,系统脱氮性能最佳,NH_(4)^(+)-N和TN的平均去除率为99.80%、91.28%,远超一级A标准,当DO过低时主要影响系统硝化能力,从而影响系统脱氮性能;C/N=5时,NH+4-N和TN的平均去除率为99.80%、91.28%,系统具有较好的脱氮效果,当C/N过低时,反硝化受到抑制,从而影响系统脱氮性能;在不同DO浓度、C/N条件下,TP平均去除率均在95%以上,远超一级A标准。据此,建议高原污水处理厂可适当降低曝气,降低运行能耗。该研究结果可为低温条件下的污水处理系统效能提升提供参考。Affected by low temperature and low pressure, the microbial activity of wastewater treatment plants in plateau area is lower, nitrogen and phosphorus concentration in the effluent is generally higher, and the energy consumption and drug consumption usually remain a high level. In this study, an A~2/O-MBR process was selected to study the effects of DO concentration and C/N ratio on nitrogen and phosphorus removal performance of a wastewater treatment system at low temperature. The results showed that when the water temperature in the reactor was 10 ℃, the HRT was 12 h, and the reflux ratio of the two-stage mixture was 200%, the MLSS of the system was 7000 mg/L, far higher than the traditional activated sludge process, and that overcome the lack of microbial activity caused by low temperature to some extent;when DO concentration was 1.0~1.5 mg/L, the denitrification performance of the system was the best, and the average removal rates of NH_(4)^(+)-N and TN were 99.80% and 91.28%, far exceeding the first-class A standard in the Integrated Wastewater Discharge Standard. When DO was too low, it mainly affected the nitrification ability of the system, thus affecting its denitrification performance;when C/N was 5, the average removal rates of NH~+_4-N and TN were 99.80% and 91.28%, respectively, and the system achieved good nitrogen removal performance. When C/N was too low, denitrification was inhibited, which affected the nitrogen removal performance;under different DO concentrations and C/N ratios, the average removal rate of TP could be stabilized at 95% above, complying with the first-class A standard. Based on the results, the aeration of plateau sewage treatment plants in daily operation can be properly reduced, to reduce the total energy consumption. The research results can also provide reference for improving the efficiency of sewage treatment systems under low temperature condition.

关 键 词：A^(2)/O-MBR 低温 溶解氧 碳氮比 脱氮除磷 

分 类 号：X703[环境科学与工程—环境工程]