底泥预处理对磷等温吸附特征及磷形态的影响

以校园河流底泥为材料,研究了通过不同预处理对有机质去除后,底泥对磷的等温吸附特征以及底泥中磷的赋存形态的转化.结果表明,对底泥曝气预处理强化了底泥对磷的吸附能力,最大吸附量(S_max)达到714.3mg/kg.不同底泥灼烧后,最大吸附量为天然底泥的1.64～2.25倍,且明显高于未灼烧底泥.对底泥曝气与对水曝气预处理使易被生物利用态磷向难被生物利用态磷转化,易被生物利用态磷较预处理前分别减少了7.02%和0.23%,而空白试验底泥的易被生物利用态磷则增加了4.85%.底泥灼烧后,SMT法不适合分析磷的赋存形态.底泥预处理后,酸性或碱性均促进了磷的释放.底泥灼烧后,在pH5～6条件下,磷的释放量低于未灼烧底泥.

Influence of different sediments pretreatment on phosphorus adsorption characteristics and phosphorus forms

Phosphorus isothermal adsorption characteristics and the transformation of phosphorus forms in sediments after removal of organic matters by different pretreatments were studied, using the sediment of campus river as material. Aerating pretreatment sediment strengthened the adsorption capacity of sediment on phosphorus, the greatest adsorption amount (Smax) reached 714.3mg/kg. After different sediments ignitions, Smax was 1.64~2.25 times of that of raw sediment, higher obviously than the sediments without ignition. The aerating pretreatments of sediment and water caused the transformation of bioavailable form to nonavailable form. The bioavailable phosphorus decreased 7.02% and 0.23% respectively compared with that before pretreatment, but the bioavailable phosphorus of the blank test sediment increased 4.85%. After ignition of sediment, adopting SMT technique to analyze the phosphorus form was not suitable. After sediment pretreatment, acidic and basic all promoted the phosphorus release. After sediment ignition, under the condition of pH 5~6, the phosphorus release amount was lower than that of no ignition.