内回流混合液DO对缺氧池脱氮的影响及控制方法  

Impact of Dissolved Oxygen in Internal Reflux Mixture on Nitrogen Removal in Anoxic Tank and Its Control Measures

作　　者：孙永利[1,2] 李鹏峰[2] 隋克俭[2] 范波[2] 周蕾[2] 郭亚琼[2] 刘俊新[1] 

机构地区：[1]中国科学院生态环境研究中心,北京100085 [2]中国市政工程华北设计研究总院有限公司,天津300074

出　　处：《中国给水排水》2015年第21期81-84,共4页China Water & Wastewater

基　　金：国家水体污染控制与治理科技重大专项(2012ZX07313-001)

摘　　要：城镇污水厂内回流混合液携带有2mg／L以上的溶解氧，将与缺氧池内的NO3^--N竞争碳源，直接影响污水处理厂的脱氮效果。根据反硝化脱氮理论及模拟试验，每1mg的DO值意味着不低于0．35mg的NO^--N去除损失量，而所携带DO总量与内回流混合液中DO浓度及回流比直接相关。据此提出了内回流混合液DO对反硝化脱氮影响预测模型，并对部分工程进行了预测。结果表明，内回流混合液DO导致形成2—5mg／L甚至更高的TN去除量损失，对污水处理厂出水TN稳定达标具有重要影响。据此提出在不改变总池容的情况下，分割形成独立消氧区的建议。The internal reflux mixture with high concentration （ ≥ 2 mg/L） of dissolved oxygen may compete with NO3- -N in anoxie tank for carbon source, which can directly affect the nitrogen removal efficiency in WWTP. According to the dcnitrification theory and simulation tests, each 1 mg of dissolved oxygen could cause 0.35 mg of nitrate removal loss in general, and the total amount of dissolved oxygen in internal reflux mixture was related to the concentration of dissolved oxygen and the reflux ratio. Accordingly, a mathematical model used for predicting the impact of dissolved oxygen in internal reflux mixture on nitrogen removal was developed, and was applied to a real project. The results showed that the nitrogen removal efficiency decreased by 2 to 5 mg/L or more due to the dissolved oxygen in internal reflux mixture, which had an important influence on meeting the discharge limit of TN for wastewater treatment plant. Finally, an independent oxygen consumption zone was suggested to be established with- out changing the existing tank volume.

关 键 词：内回流混合液 溶解氧 脱氮影响预测模型 消氧区 

分 类 号：X703[环境科学与工程—环境工程]