Abstract: The sequence of factors affecting the removal ratio of NH3-N and PO43—-P is as follows: concentration>pH> Mg∶N >P∶N> reaction time, through orthogonal experiment. The regress equation of the quantity of PO43—-P and NH3-N in the treated water is as follows: y(PO43—-P)=-3 041.57-2.76z1+2 307.2z2+3 075.5z3-2 310z2z3 (z1=pH，z2=Mg∶N，z3=P∶N), y(NH3-N)= 1 104.84-50.76z1-45.5z2-515.5z3, through once regress orthogonal experiment. The regress equation has high notability. When NH3-N is 1400 mg/L, the best treatment condition is as follows: pH=9.5, Mg∶N=1.2，P∶N=1.03, when reaction time is 30min, and stirring speed is 200r/min. On these treatment conditions, the removal ratio of PO43— is 99.73%; the quantity of PO43—-P in the treated water is 8.66 mg/L; the removal ratio of NH3-N is 98.83%; the quantity of NH3-N in the treated water is 16.45 mg/L.

Key words: magnesium ammonium phosphate, removal of nitrogen and phosphorus, effect factors, linear regression orthogonal experiment

摘要： 通过正交实验得出影响氨氮和磷酸盐去除率因素的主次顺序为：浓度>pH> Mg∶N >P∶N>反应时间。通过一次回归正交实验得出残磷量和残氮量的回归方程为：y(残磷量)=-3 041.57-2.76z1+2 307.2z2+3 075.5z3-2 310z2z3（其中z1=pH，z2=Mg∶N，z3=P∶N），y(残氮量)=1 104.84-50.76z1-45.5z2-515.5z3，回归方程高度显著。在氨氮浓度为0.1 mol/L (1 400 mg/L)及磷酸盐为相应浓度时，在兼顾处理出水的含盐量、残磷量和残氮量尽量低的前提下，最佳的实验条件为：pH=9.5，Mg∶N=1.2，P∶N=1.03，反应时间为30 min，搅拌速度为200 r/min。在上述实验条件下PO43--P的去除率为99.73%，处理出水中的PO43--P含量为8.66 mg/L，NH3-N的去除率为98.83%，NH3-N含量为16.45 mg/L。

关键词: 磷酸铵镁, 脱氮除磷, 影响因素, 一次回归正交实验