高铁酸盐溶液的制备与去除氨氮的实验研究

根据现场制备要求,优化传统高铁制备工艺,得出工业化现场制备液体高铁的最佳工艺条件,进而用于水库水氨氮的去除研究。实验结果表明,通过优化工艺所制得高铁浓度为24 g/L左右,铁转化率为80%左右。高铁对氨氮的去除效果随高铁与氨氮的摩尔比增大而增大,当摩尔比为0.45时,高铁对水源水中氨氮的去除率可达75%;在保证高去除率的基础上,通过延长絮凝反应时间,可降低高铁投加量;如果采用高铁预氧化,聚合铝或三氯化铁作絮凝剂,可提高对氨氮的去除率,还能大幅度降低高铁投加量,缩短反应时间。

Preparation of Ferrate Solution for Removing Ammonia-nitrogen from Drinking Water

The in-situ preparation of dissolved ferrate and its application to removing the NH_3-N from drinking water source were investigated.The concentration of dissolved ferrate could reach about 24 g/L and the ratio of trivalent iron transition to ferrate was about 80% under the optimum conditions.The removal efficiency of NH~3-N was enhanced with the increase of the molar ratio of ferrate and NH_3-N.75% removal efficiency could be obtained when the molar ratio between ferrate and NH_3-N reached 0.45.Based on the high removal efficiency of NH_3-N,the consumption of ferrate could be reduced by extending flocculent time.On the other hand,poly-aluminium or ferric chloride used as coagulant could also enhance the removal efficiency of NH_3-N by ferrate pre-oxidation with lower ferrate dosage and shorter reaction time.