苏州城市河道底泥对磷酸盐的吸附与释放特征  

Characteristics of adsorption and desorption of phosphate by sediments in the Suzhou River,East China.

作　　者：冯海艳[1] 李文霞[1] 杨忠芳[1] 阮晓红[2] 刑雅囡[2] 

机构地区：[1]中国地质大学(北京)地球科学与资源学院,北京100083 [2]河海大学环境科学与工程学院,南京210098

出　　处：《地学前缘》2006年第1期113-118,共6页Earth Science Frontiers

基　　金：国家"863"项目(2003AA601070);"苏州水环境质量改善与综合示范项目子课题:江南城市河网水环境质量评价指标体系建立"

摘　　要：为了探讨苏州古城区河道底泥对磷酸盐的吸附-释放特征,文中分别从改变上覆水的pH值、底泥吸附-释放动力学和等温吸附实验三个方面进行了研究。结果表明:(1)随着上覆水pH值的增大,苏州河道底泥对磷的吸附量逐渐减小;(2)底泥对磷的吸附过程是一个复合动力学过程,通常包括快吸附和慢吸附两个过程。底泥对磷的快速吸附在2h内快速进行,之后为慢吸附过程,到6h左右,基本达到一种动态吸附平衡;底泥对磷释放的动力学过程也包括快释放和慢释放过程。底泥释放磷在1·5h内快速进行,之后进入慢释放过程,磷酸盐含量基本稳定,达到释放平衡;(3)底泥具有较大的吸附磷的能力。随着上覆水的磷酸盐浓度增高,底泥吸附磷酸盐的量也增加。上覆水与底泥的比值越大,底泥对磷的吸附率越小。The characteristics of adsorption and desorption of phosphate by sediments in the Suzhou River, East China are investigated. These include the effect of pH of overlying water on adsorption, adsorption and desorption kinetics, and isothermal adsorption. The results are as follows： （1） With an increase of the pH value of the overlying water, the adsorption capacity of phosphate in sediment decreases. （2） The kinetics of phosphate adsorption and desorption exhibit a complex behaviour, including a fast and a slow adsorption and desorption process. The fast phosphate adsorption process lasts 2 hours, then the slow process lasts about 6 hours before reaching the adsorption equilibrium. The fast phosphate desorption process occurs within 1. 5 hours, then the slow phosphate desorption process takes place, and the desorption equilibrium reaches a relatively stable concentration of PO4-P. （3） The sediment has a strong phosphate adsorption ability. With an increase of PO4-P concentration, the PO4-P adsorption capacity on sediment increases. The higher the proportion of water to sediment, the lower the phosphate absorption capacity on sediment would be.

关 键 词：磷酸盐 底泥 吸附 释放 

分 类 号：P642.132[天文地球—工程地质学] X13[天文地球—地质矿产勘探]