铁尾矿制备聚合硫酸铁实验及造纸污水处理效果初步评价

为了分析外界因素对制备聚合硫酸铁的影响,开展了不同条件下的酸浸还原实验和聚合合成实验,优化了实验条件,进而分析不同pH、不同絮凝剂用量以及不同沉降时间作用下,聚合硫酸铁对污染水的处理效果。结果表明：酸浸实验中尾矿全铁浸出实验的最佳温度为100 ℃,最佳搅拌时间为2 h,最佳搅拌速度为300 r/min;还原试验中硫酸亚铁还原率的最佳还原温度为60 ℃,最佳还原时间为1.5 h,还原铁粉的过量系数为1.10%。聚合合成实验中最佳聚合温度为35 ℃,最佳聚合时间为0.4 h;此条件下,n（双氧水）∶n（Fe²⁺）∶n（磷酸钠）为0.08∶1∶0.07时,聚合效果最优。在pH为7中性环境中,聚合硫酸铁的质量浓度为2.0 g/mL,沉降时间为0.3 h时,污水的余浊值最小,对于污水的处理效果最好。

Preparation of polymeric ferric sulfate from iron tailings and preliminary evaluation of papermaking wastewater treatment

In order to analyze the influence of external factors on the preparation of polyferric sulfate,acid leaching reduction experiments and polymerization synthesis experiments under different conditions were carried out.The experimental condi-tions were optimized,and then the treatment effect of polyferric sulfate on contaminated water was analyzed under different pH,dosage of flocculating agent and settling times.The results showed that the optimal temperature of tailings all iron leaching experiments in acid leaching experiment was 100 ℃,the best stirring time was 2 h,and the best stirring speed was 300 r/min. The optimum reduction temperature of ferrous sulfate reduction rate in the reduction test was 60 °C,the optimal reduction time was 1.5 h,also the excess coefficient of reduced iron powder was 1.10%.The optimum polymerization temperature in the polymerization synthesis experiment was 35 ℃,and the prime polymerization time was 0.4 h.Under these conditions,polymerization effect was best at an n（hydrogen peroxide）∶n（Fe²⁺）∶n（sodium phosphate） ratio of 0.08∶1∶0.07.At neutral environment with pH of 7,the polyferric sulfate mass concentration of 2.0 g/mL and settling time of 0.3 h resulted in the smallest turbidity value and the best treatment effect for wastewater.