改进MAP沉淀法处理氨氮废水的研究

STUDY OF MAP PRECIPITATION IMPROVEMENT FOR AMMONIACAL NITROGEN WASTEWATER TREATMENT

为了降低磷酸铵镁(MAP)化学沉淀法处理氨氮废水的药剂使用成本,探索了MAP的热分解及热解产物循环用于氨氮废水处理药剂的可行性。结果表明,控制反应体系的pH为9.5时,可得到纯度高的MAP沉淀物;将MAP沉淀物直接热分解,可将氨脱除,热解固体产物能吸附氨氮,循环用于氨氮废水处理药剂是可行的;实际操作时,控制热解温度为130℃、热解产物与氨氮的摩尔比为1:1、氨氮吸附体系的pH为9.5是合适的,对起始浓度为1 000 mg/L的氨氮废水的去除率达80%。

This study works on thermal decomposition of magnesium ammonium phosphate（MAP） and the feasibility of reusing its thermal decomposition product as an agent in ammoniacal nitrogen wastewater treatment in order to reduce the cost of the treatment agent using MAP chemical precipitation. The results show that high-purity MAP can be abstracted by maintaining the pH level at 9.5. Thermal decomposing MAP will eliminate ammonia, and the thermal decomposition product can absorb ammoniacal nitrogen, indicating that it is feasible to reuse the product in the treatment process. In practice, maintain the decomposing temperature at 130 degree Celsius, mole ratio between decomposition product and ammoniacal nitrogen at1：1, and pH level at 9.5 will optimize the adsorption of ammoniacal nitrogen, for ammoniacal nitrogen wastewater with an initial concentration of 1 000mg/L, its removal rate reaches 80%.