利用含锌硫酸废水制备聚硅酸铁锌及处理含肼废水

Using sulfuric acid wastewater containing zinc for the preparation of polysilicate-ferric-zinc and the treatment of hydrazine-containing wastewater

以含锌硫酸废水、铁屑、硅酸钠为原料制备聚硅酸铁锌絮凝剂。对制备条件的优化结果表明，当SiO2质量分数为0.020～0.025，n（Fe＋Zn）/n（Si）为1.5～2.0，硅酸活化的pH为1.56～2.12，活化时间为12～16 h时，制备的聚硅酸铁锌絮凝剂的絮凝性能优良。用制备的聚硅酸铁锌絮凝剂二段处理含肼废水，结果表明，经该絮凝剂处理后，废水COD从7065 mg/L降低到1235 mg/L，COD去除率达到了82.5%，pH从13～14降低到9～10，降低了含肼废水后续生物处理的负荷和冲击。

Poly-silicate-ferric-zinc flocculant has been made from sulfuric acid wastewater containing Zn2＋,iron scraps and sodium silicate. The results show that when the mass refraction of SiO2 is 0.020-0.025,n（Fe＋Zn）/n（Si） is 1.5-2.0,silicic acid activated pH is1.56-2.12 and activation time is 12-16 h. The flocculation capacity of the pre-pared poly-silicate-ferric-zinc flocculant is excellent. The prepared poly-silicate-ferric-zinc flocculant has been used for two-stage treating the hydrazine-containing wastewater. The results show that after being treated by this floccu-lant,the wastewater COD can be decreased from 7 065 mg/L to 1 235 mg/L,COD removing rate reaches 82%,and pH is decreased from 13-14 to 9-10. The load and attack of subsequent biochemical treatment of wastewater con-taining hydrazine has been decreased.