金属盐复合混凝剂制备及除磷效果试验

Preparation of Metal Salt Composite Coagulant and its Phosphorus Removal Effect

针对传统混凝剂除磷效果差的问题,以盐酸和硅酸钠为主要原材料,制备一种复合聚硅酸铝锌混凝剂.结合正交试验,得到复合聚硅酸铝锌的最佳制备工艺为:硅酸活化时间:2 h,n(Al+Zn)/n(Si)=1∶1;n(Al)/n(Zn)=2∶1;利用响应曲面法对复合聚硅酸铝锌的最佳除磷工艺进行优化,得到除磷最佳条件为:pH=6,反应时间25 min,沉淀时间30 min,此时复合聚硅酸铝锌混凝剂除磷率高达9.2%,高于常用的混凝剂,表明制备的复合聚硅酸铝锌混凝剂可行.

In view of the poor effect of traditional coagulant in phosphorus removal,a composite polysilicate aluminum zinc coagulant was prepared by hydrochloric acid and sodium silicate as the main raw materials.Combined with orthogonal test,the optimum preparation technology of the composite polysilicate aluminum zinc is:the activation time of silicic acid is 2 h,n(Al+Zn)/n(SI)=1∶1;n(Al)/n(Zn)=2∶1;by response surface method,the best phosphorus removal technology of the composite polysilicate zinc was optimized,of which the best conditions for phosphorus removal were pH=6,reaction time 25 min,precipitation time 30 min,and at this time,the phosphorus removal rate of the composite polysilicate aluminum zinc coagulant was up to 9.2%,which was higher than that of the common coagulant,indicating that the composite polysilicate zinc coagulant prepared in this paper is feasible.