三峡库区泥沙对磷的吸附试验研究

采用三峡库区长寿段、忠县段、奉节段泥沙为研究对象，通过室内试验，研究了泥沙对磷的吸附动力学及等温吸附过程。结果表明，泥沙对磷的吸附存在一个先快后慢的过程，快速反应基本都在前5h，随后水中磷酸盐浓度下降速度逐渐变缓，12h后基本可达平衡，准二级动力学方程能很好地拟合泥沙对磷的吸附动力学过程；单位质量泥沙对磷的平衡吸附量与液相磷平衡质量浓度成正比，且在液相磷平衡质量浓度较低时上升较快，Langmuir及Tempkin模型对等温吸附过程的拟合优于Freundlich模型，等温模型参数随着泥沙浓度的变化表现出一定的规律性；随着泥沙浓度的增大，三地区泥沙对磷的吸附速率增大，但单位质量泥沙对磷的平衡吸附量减少；长寿、忠县、奉节三个地区的泥沙在相同实验条件下表现出不同的吸附特性，考虑是由于其理化特性的差异而引起。

Study on Phosphorus Adsorption of Sediment in the Three Gorges Reservoir Area

Using the sediments from the Changshou Section, Zhongxian Section and Fengjie Section of the Three Gorges Reservoir Area as the research object, the adsorption kinetics and isothermal adsorption processes of phosphorus on sediments were studied through laboratory tests. The results showed that there was a rapid and slow process of phosphorus adsorption on sediment, and the rapid reaction was basically in the first 5 hours. The subsequent decrease in phosphate concentration in the water gradually slowed down and reached equilibrium after 12 hours, Pseudo-second-order kinetic equation can well fit the adsorption kinetics of phosphorus on sediment; The equilibrium adsorption of phosphorus per unit mass of sediment is proportional to the equilibrium concentration of liquid phosphorus, and it rises quickly when the liquid phosphorus balance mass concentration is low, and Langmuir and Tempkin Models Better Than Freundlich Models for Isotherm Adsorption, the isothermal model parameters show some regularity with the change of sediment concentration; With the increase of sediment concentration, the adsorption rate of phosphorus in sediments in the three regions increased, but the equilibrium adsorption capacity of phosphorus per unit mass of sediment decreased; The sediments in the three regions of Changshou, Zhongxian, and Fengjie exhibited different adsorption characteristics under the same experimental conditions, the consideration was due to differences in physical and chemical properties.