磷酸铵镁法循环处理高浓度氨氮废水

Recycle Treatment for Wastewater With High Concentration of Ammonium-nitrogen by MAP

提出了磷酸铵镁(MAP)法循环处理氨氮废水的新方法。在对MAP的热分解进行特性分析的基础上,利用MAP在100℃左右温度下直接进行热解2 h的产物来处理高浓度氨氮废水。研究表明,对于NH4+质量浓度为900 mg/L的废水,虽然随着循环进行氨氮去除率逐渐减少,但第5次循环后氨氮去除率仍然高于70%。此方法的特点是磷酸铵镁(MAP)热分解时,可回收高浓度氨水而不再需要投加大量的镁盐和磷盐,实现氨氮的回收和MAP的循环使用。

MAP method is proposed to dispose the ammonium - nitrogen containing wastewater. Based on some analysis the decomposition of the magnesium amnonium phosphate（MAP）, the residues of magnesium ananonium phosphate deeomposed by heating under 100 ℃ in 2 h are repeatedly used as the sources of phosphate and magnesium for the removal of high ammonium concentration from wastewater. It shows： to wastewater with initial concentration of NH4^＋ 900 mg/L, the ammonium removal decreases gradually following the increase of MAP, but in the 5th cycle, ammonium removal rate is still over 70%. The advantages of this method is that high concentration ammonia solution can be recovered by heat deecomposition of MAP and large amounts of Magmesium and Phosphorus is not needed to be added, so the recovering of ammonia- nitrogen and the recycling use of MAP can he realized.