回流量对3AMBR工艺运行效能的影响

摘要

To solve drawbacks with excess aeration and high energy consumption of the 3AMBR process,and to investigate effluent concentration and energy consumption under different recirculation flow rate from MBR,the trend of DO and nitrogen in each processing unit were comprehensive monitored based on a 3AMBR sewage treatment plant. The results show that dissolved oxygen from the MBR by improving recirculation flow rate from membrane tank can be provided to aerobic tank to achieve high ammonia-nitrogen removal rate,which can decrease aeration quantity for saving energy. Besides,anoxic pond in hypoxia environment can be ensured by internal reflux and effluent concentration of total nitrogen can be reduced from 12. 9 mg/ L to 7 mg/ L.%以某3AMBR城市污水处理厂为研究对象，针对现状工艺存在的好氧区过量曝气及能耗过高的问题，对该厂生化单元沿程DO和氮素的变化做全面跟踪监测，以考察不同膜池混合液回流量对出水水质及能耗的影响。试验结果表明：通过将膜池回流比由3．5增加至6．6，将其携带的 DO用于好氧区的生化需求，可部分替代鼓风曝气的氧供应效果，降低能耗，维持好氧区的硝化环境，满足氨氮的去除；并通过内回流改善厌氧、缺氧段的反硝化环境，提高脱氮效率，实现出水TN 平均值由12．9 mg／ L降至9．7 mg／ L。