自然有机物对地下水混凝除铁的影响试验研究

Research on the impact of natural organic matter on coagulation removal of iron from groundwater

通过模拟试验,考察了自然有机物的浓度、分子质量以及溶液的pH、温度对地下水混凝除铁的影响,并研究了预氧化在混凝除铁中的作用。结果表明,有机物的浓度越高、分子质量越大,有机铁的去除率越高。当Fe2+与分子质量>10 ku的有机物络合时,用混凝除铁能取得良好的效果;当Fe2+与分子质量<4 ku的有机物络合时,采用预氧化混凝工艺能达到较好的除铁效果。在pH6.0～7.5的范围内,降低pH有利于混凝除铁。温度升高对混凝除铁有利。

By simulating experiments,the effects of the molecular weight and the concentration of natural organic matter on coagulation removal of iron from groundwater have been investigated,and some impact factors such as pH, solution temperature on them have been studied. The action of pre-oxidation on coagulation removal of iron has been studied as well. The experiments show that the removal of iron increases with the increasing of the molecular weight and the concentration of organic matter. Alum coagulation is very effective on the removal of iron（ Ⅱ ） complexed by organic matter with molecular weight greater than 10 000 u. Iron （ Ⅱ ） complexed by organics with molecular weight less than 4 000 u is amenable to be removed by pre-oxidation followed by alum coagulation, pH value decreasing is beneficial to coagulation removal of complexed iron over the pH range from 6.0 to 7.5. When solution temperature increases, removal efficiency of complexed iron also increases.