BAF去除氨氮关键影响因素研究

Factors Affecting Ammonia Nitrogen Removal in BAF

为探讨曝气生物滤池去除氨氮的关键因素,选取沈阳仙女河污水处理厂（40万t/d）现场进行实地研究。通过测定不同条件下（pH、进水COD浓度、溶解氧、温度、水力负荷）的氨氮去除率,并进行主成分分析结果显示,影响BAF工艺脱氮的关键因素是温度、溶解氧和水力负荷。当温度在14~30℃之间时,氨氮的去除率一直维持较高,当温度低于14℃时,氨氮的去除率较低;随着溶解氧浓度的增大,氨氮的去除率也随之升高,当溶解氧增加到5.6 mg/L时,氨氮的去除率达到80%~90%,接近饱和状态;在水力负荷为3.08~4.15 m3/（m.2h）之间时,氨氮的去除率上升,超过该值,则氨氮去除率下降。

BAF（biological aerated filter） system at Xiannvhe WWTP in Shenyang City was investigated about the factors affecting its efficiency of NH4＋-N removal,which included pH,COD of influent,DO and temperature of the wastewater,as well as hydraulic load of the ABF.Using method of PCA（principal components analysis） to analyze the experimental data measured,results indicated that the main factors were DO and temperature of the wastewater and hydraulic load;meanwhile ranges of these affecting factors were presented,e.g.,NH4＋-N removal maintained high when the temperature ranged between 14 ℃ and 30 ℃,but dropped when temperature was below 14 ℃,in addition,hydraulic load exceeding 4.15 m3/（m2·h） would lead to decreases of removal rate of NH4＋-N.