强化磷酸铵镁法回收源分离黄水中氮磷的试验研究

Experimental study on recovery of nitrogen and phosphorus from source separated urine enhanced by magnesium ammonium phosphate precipitation process

为强化氮磷的回收与资源化利用,采用磷酸铵镁法处理源分离黄水。分析了pH值、Mg∶N∶P(摩尔比)、搅拌时间、搅拌速度、温度等因素对氮磷回收效果的影响,考察了pH值调节方式对氮磷回收的强化作用。结果表明:pH值调节方式和Mg∶N∶P是影响氮磷回收效果的主要因素;改善pH值的调节方式可以提高氮磷回收率并节省镁源和磷源的投加;在初始pH值为9且首次反应结束后pH值回调至9、Mg∶N∶P=1.1∶1∶1的条件下,氮、磷回收率分别达到82.6%和94.5%,获得的沉淀晶体呈斜方晶型且杂质较少。

Magnesium ammonium phosphate precipitation process was used for source separated urine treatment to improve the recovery and resource utilization of nitrogen and phosphorus.The effects of pH,Mg∶N∶P(molar ratio),stirring time,stirring speed,and temperature on the recovery of nitrogen and phosphorus were analyzed,and the effect of pH adjustment method on enhancing nitrogen and phosphorus recovery was investigated.The results showed that pH adjustment method and Mg∶N∶P(molar ratio)were the main impact factors.Changing the pH adjustment method could improve the recovery of nitrogen and phosphorus and reduce the dosage of magnesium source and phosphorus source.The recovery rates of nitrogen and phosphorus were 82.6%and 94.5%,respectively,when the initial pH was 9,the pH was adjusted back to 9 again after the first reaction,and the Mg∶N∶P(molar ratio)is 1.1∶1∶1.Moreover,the precipitation crystals which obtained in the above process were orthorhombic with less impurities.