聚硅酸铁镁水处理剂的制备及应用研究

Preparation and coagulation behavior of a ferric polysilicate coagulant modified with magnesium

利用复合共聚法制备了聚硅酸铁镁(PSiFM)絮凝剂,采用IR、SEM等手段对PSiFM进行了表征,并研究了该絮凝剂pH、电导率、化学需氧量等随保存时间的变化规律。结果显示PSiFM形成了有利于发挥电中和、吸附网捕等絮凝作用的结构,比未加Mg的聚合硫酸铁(PSiF)絮凝剂有更好的效果。最后采用模拟水样和实际水样分别进行了PSiFM的应用性能研究,结果表明与市售聚合硫酸铁(PFS)絮凝剂相比,PSiFM具有较好的絮凝效果,CODCr去除率可达80%左右,固体悬浮物去除率可达90%左右。

A ferric polysilicate coagulant modified with magnesium （PSiFM） has been prepared by a composite-pol- ymerization method. The coagulant prepared under the optimized conditions was characterized by infrared spectroscopy and scanning electron microscopy. It was found that the structure of PSiFM favored its flocculation. Further- more, by measuring the changes in pH, conductivity, and chemical oxygen demand CODcr it was found that PSiFM had a superior effect to the parent flocculant before modification by magnesium （ ferric polysilicate, （PSiF） ）. Fi- nally, the coagulation behavior of PSiFM was assessed by studying the reduction of CODcr and suspended solids （SS） in diatomite model suspensions and an actual water sample. The results suggested that the coagulation per- formance of PFSiM was superior to other iron-based coagulants, the CODcr removal ratio was up to 80% , and the SS removal ratio was up to 90%.