硫铁矿烧渣制备聚硅酸铁及其絮凝效果研究

Study on flocculation of poly ferrotremolite prepared with pyrite cinders

以硫铁矿烧渣为原料酸浸制取硫酸亚铁,并与硅酸钠制备高效絮凝剂聚硅酸铁(PSF)。研究了硫铁矿烧渣的酸浸条件,当质量分数40%的硫酸用量为理论值的1.2倍,质量液固比为5∶1,浸出温度为100℃,搅拌速度为400r/min时,浸取3h,硫铁矿烧渣中全铁的浸出率可达95%。探讨了影响PSF絮凝性能的主要因素,如铁硅摩尔比、硅酸活化时间、PSF的用量、熟化时间、污水的初始pH值等。结果表明PSF处理低温低浊水效果较好,pH适应范围宽。在n(铁)∶n(硅)=1∶1、硅酸活化40min、25℃时熟化3d的条件下,PSF对东湖污水的最大絮凝率可达86%。

High efficient flocculant of polysilicate ferrite （PSF） was prepared by sodium silicate and ferrous sulphate by acid leaching pyrite cinders. The acid leaching conditions of pyrite cinders were studied. When the mass fraction of sulfuric acid is 40%, its dosage is 1.2 times the theoretical value, the liquid solid mass ra tio of sulfuric acid to cinder is 5 ： 1, reaction temperature 100 ℃, stirring speed 400 r/min, and acid leaching time 3 hrs, the leac hing rate of all iron can reach 95%. The main factors which affect the performance of poly silicate ferric were also investigated, such as iron silicon tool ratio, activation time of silicic acid, dosage and ageing of PSF, initial pH value of wastewater and so on. The re sults show that PSF has good elfect on treating water with low temperature and turbidity and wide adaptability of pH ranges. Whenn （Fe） n （Si）：1： 1, activation time of silicic acid is 40 min, ageing time of PSF at 25℃ 3 days, the largest flocculation rate of PSF to East Lake wastewater can reach up to 86%.