MAP处理苯胺基乙腈生产废水中的氨氮

Study on the treatment of NH_3-N from N-phenylglycinonitrile wastewater by MAP

分析了磷酸氢镁、氧化镁+磷酸氢二钠、氧化镁+磷酸二氢钠、氧化镁+磷酸4种药剂组合对苯胺基乙腈生产废水中氨氮的去除效果,并结合药剂的经济性、投加方便性、配比调整灵活性和工艺衔接可行性选定最佳药剂组合。结果表明,氧化镁+磷酸为MAP处理苯胺基乙腈生产废水中氨氮的较佳药剂组合,其最佳反应条件:pH=9.5,m(Mg)∶m(N)=2.5∶1,m(N)∶m(P)=1∶1.2,废水中的氨氮从2 000 mg/L降到150 mg/L以下,氨氮去除率接近90%。

The effects of the combination of four kinds of chemicals ： MgHPO4, MgO＋Na2HPO4, MgO＋NaH2PO4 and MgO ＋H3PO,, on the removal of ammonia-nitrogen from N-phenylglycinonitrile wastewater has been analyzed. It is selected as the best chemical combination, because of the economical efficiency of the precipitants, the convenience of the dosing process of precipitants, the flexibility of ratio regulation and the feasibility of process linking-up. The optimum reactions conditions have been obtained. The results show that MgO＋H3PO4 is the best precipitant in the treatment of ammonia-nitrogen in N-phhenylglycinonitrile wastewater by MAP. The optimum reaction conditions are as follows ： pH =9.5, m （Mg） ：m （N） =2.5：1, m （N） ：m （P） = 1 ： 1.2. The concentration of ammonia-nitrogen has dropped from 2 000 mg/L to less than 150 mg/L, and the removing rate of ammonia-nitrogen is close to 90%.