固体钙铁复合絮凝剂的制备及应用研究

以七水硫酸亚铁、氯化钙和浓硫酸为主要原料,采用鼓风氧化工艺制备了固体聚合硫酸铁(SPFS)。在铁钙总物质的量不变、不同铁钙比的条件下合成了固体钙铁复合絮凝剂。对SPFS和钙铁复合絮凝剂进行了红外光谱分析和活性成分的测试,为了测试其性能,分别进行了高岭土模拟浊度废水的去浊度和腐植酸溶液的脱色研究。结果表明,钙铁复合絮凝剂表现出了较SPFS更好的去浊能力,而且随着钙组分的增多,这种趋势越明显;适量钙铁比的复合絮凝剂能提高脱色效果;在去浊度的测试中,各种絮凝剂的最佳投药量(以Fe计)为15 mg.L-1,最佳pH为8～10,去浊率可达98%以上;在脱色的研究中最佳投药量(以Fe计)为20～40 mg.L-1,最佳pH为3～7,脱色率在90%以上。

固体聚合铝铁絮凝剂的制备及应用研究

采用鼓风氧化工艺成功制备了不同n(Fe)∶n(Al)的固体PAFS。测定了其形态分布、红外光谱和XRD。为考察产品的混凝性能,进行了高岭土模拟浊度废水的去浊度实验和酸性大红溶液的脱色研究。结果表明:PAFS较PFS具有更好的去浊能力和脱色效果;在去浊度测试中,絮凝剂的最佳投药量18 mg/L,最佳p H为9,去浊率达98%;在脱色研究中最佳投药量为32 mg/L,最佳p H为9,脱色率达95%,絮凝效果与PAFS的成分具有一定关系。

Removal of Turbidity and COD from a Synthetic Water Sample by Coagulation

The main objective of this research was to study the removal of turbidity and COD （chemical oxygen demand） from a synthetic water sample. The water sample was treated chemically by coagulation. Two inorganic coagulants were used, ferric chloride and the double salt potassium-aluminium sulphate. The optimum coagulant dosage and working pH were examined. The results for ferric chloride as coagulant showed that the maximum removal efficiency （%） of COD was achieved at pH 6 with a dosage of 100 mg-L-1 and the maximum removal efficiency （%） of turbidity at pH 5 with a dosage of 500 mg.L-1. For double salt, as coagulant, the maximum removal efficiencies （%） of COD and turbidity were achieved at pH 6 with a dosage of 3,500 mg.L-1. An extensive comparison with results from previous studies was also described in this research.