用生产活性白土的废水合成聚合硫酸铝铁

SYNTHESIS OF POLYMERIC ALUMINUM FERRIC SULFATE BY USING WASTE WATER IN THE ACTIVATED CLAY PRODUCTION

采用活性白土废酸循环活化工艺中排出的高、低含量2种废水为原料合成了液体聚合硫酸铝铁(PAFS)絮凝剂,研究确定了其优化工艺条件。用合成的PAFS对鱼塘污水进行除浊和脱除COD实验,并与硫酸铝(AS)絮凝剂使用效果进行比较。结果表明,当碱化剂碳酸钠用量为5g、反应温度为80℃、反应时间为2h时,产品盐基度达到51.0%;PAFS对污水浊度去除率可达88.7%,混凝除浊性能与市售AS絮凝剂相当,且其污水COD去除率为79.3%,优于AS絮凝剂。

A new kind of composite flocculant, polymeric aluminum ferric sulfate （PAFS）, was synthesized by using the two kinds of waste water with different concentrations ofAl3＋, Fe3＋ and sulfitric acid as raw materials. The synthetic process conditions were investigated, and the coagulation-floceulation performance （turbidity and COD removal performance） of the PAFS was also studied and compared with that of aluminum sulfate （AS）. The results showed that the optimum synthetic conditions of alkalizer dosage, reaction temperature and time for PAFS production were of 5 g, 80 ℃ and 2 h, respectively while the basicity of the PAFS reached 51.0% and the highest turbidity and COD removal efficiency were 88.7% and 79.3%, respectively. The turbidity removal efficiency of PAFS was as good as that of AS, while the COD removal efficiency was better than that of AS.