污染物离子在粘土介质中扩散系数和分配系数的测定(英文)

介绍了利用一种自制的特殊装置,测定污染物离子在粘土介质中迁移的扩散参数D和分配系数Kd的方法。通过一系列污染物在上海粘土中的纯扩散迁移试验,系统中污染物的质量不变,源浓度随试验的进行是下降的,运用一个简单的理论模型,通过拉普拉撕(Laplace)变换方法,对一个单独的试验,可同时推断出扩散系数和分配系数。通过拉普拉撕转换程序求出了阴离子(Cl-)和阳离子(K+,Ca2+,Zn2+,Cu2+)的扩散系数D和分配系数Kd。试验结果发现:阴离子在粘性土壤中的显扩散系数比阳离子的大;一价阳离子K+的显扩散系数比二价阳离子的大。

Laboratory determination of diffusion and distribution coefficients of contaminants in clay soil

A technique was described for determining the diffusion coefficients and distribution coefficients of contaminants passing through saturated clay samples.The technique was illustrated with reference to a number of laboratory tests involving diffusion migration of contaminants through a clayey soil of Shanghai,P.R.China.The mass of contaminant in the system was kept constant and so source leachate concentration decreased during each test.A simple theoretical model was used to analyze the test and it was shown that the diffusion coefficient and distribution coefficient from a single test could be deduced by Laplace transform method.Diffusion coefficients and distribution coefficients of Cl-,K+,Ca2+,Zn2+,Cu2+ were calculated by Laplace transform program.If was shown that the apparent diffusion coefficient of anion Cl-through the clay samples was much larger than those of cations,and the apparent diffusion coefficient of cation K+ was smaller than those of divalent cations.