MAP沉淀法同步脱除水中氮磷的影响因素

采用磷酸铵镁沉淀法(MAP法),以MgCl2.6H2O为沉淀剂同步脱除水中氮磷。结果表明pH对氮磷的去除效果影响较大,当pH为10.5时,氮磷的去除效果达到最佳;致浊物质的存在对氨氮的去除有促进作用,低浊条件有利于磷的去除,而高浊条件对磷的去除无明显影响;较低浓度的HCO3-促进氮磷的去除,而浓度较高时抑制氮磷的去除;SO42-的存在不利于氨氮的去除,而对磷的去除略有促进作用;钙离子对氮磷的去除影响较大,当钙离子和镁离子的浓度相当时,会抑制MAP沉淀的生成。

Influencing Factors of Simultaneous Removal of Nitrogen and Phosphorus by MAP Precipitation Process

The removal of nitrogen and phosphorus by using the method of magnesium ammonium phosphate precipitation(MAP precipitation) was studied.The results show that pH value has the large effects on the removal rate of nitrogen and phosphorus,and there is the best removal effect of nitrogen and phosphorus when pH is 10.5.When turbidity exists in nitrogen and phosphorus containing water,the removal rate of ammonia nitrogen increases,low turbidity is helpful for removal of phosphorus,but high turbidity has not an evident effect on the removal of phosphorus.When HCO3-concentration is low,the removal rate of nitrogen phosphorus increases,but the high concentration of HCO3-in the water impedes the removal of nitrogen and phosphorus.The presence of SO42-is not conducive to the removal of ammonia nitrogen,but SO42-is helpful for phosphorus removal.Ca2+ has a good effect on the removal of nitrogen and phosphorus,when concentration of calcium equals to concentration of magnesium ion,it will impede MAP precipitate formation.