海水MAP法去除N、P废水实验研究

海水中富含大量的镁盐,利用镁盐和废水中的氮、磷生成白色的磷酸铵镁沉淀,可以实现废水中氮磷的脱除。本研究首先测出海水中镁的含量,然后根据镁含量设计正交试验开展研究。实验结果表明,对于废水中氮元素的去除,时间因素的影响程度较大,对于废水中磷元素的去除,pH值的影响程度较大;当pH=9.5,n(Mg2+):n(NH4+):n(PO34-)=1.3∶1∶1.08,反应时间为60 min时,氮磷的去除率可以达到63.01%和95.39%。因此,利用海水中的镁盐,去除废水中的氮磷元素,可以实现海水资源的有效利用,同时,可以提高去除氮磷的效率,降低废水处理的费用。本研究可实现氮磷废水处理的同时,实现海水资源化利用。

Removal of Nitrogen and Phosphorus in Wastewater by Magnesium Ammonium Phosphate Process with Seawater

Seawater contains large amounts of magnesium.Using the magnesium salt in seawater as precipitant can remove the phosphate and ammonium in wastewater and leads to formation of magnesium ammonium phosphate.The content of magnesium in seawater was determined by complexometric titration,then orthogonal design for treating nitrogen and phosphorus wastewater was studied.The results show that time has great impact for treating nitrogen and the impact of pH value on phosphorus is greater.When pH value is 9.5,mol ratio of magnesium,ammonia-nitrogen and phosphorus is 1.3 ∶ 1 ∶ 1.08,reaction time is 60 min,the removal rate of ammonia-nitrogen and phosphorus are 63.01% and 95.39%,respectively.This study not only removes nitrogen and phosphorus in wastewater,but also realizes source utilization of seawater.