假设填埋场下部为三层结构体系,且渗流场稳态,建立了污染物二维运移控制方程。在控制方程中分别考虑垃圾降解效应、压实黏土衬里的非线性吸附特性、滞水层与含水层的线性吸附特性及各向异性。采用数值分析方法对某一假想填埋场进行具体计算。通过变动参数计算与分析,计算结果表明:压实黏土衬里和滞水层的垂直弥散系数为污染物二维运移的敏感因素。仅考虑压实黏土衬里的非线性吸附特性下,复合参数S1,m为污染物运移的敏感因素,当S1,m取值较大时,污染物的水平向运移能力增强,而对吸附强度K1,1不敏感。滞水层线性吸附对污染物运移影响显著而含水层吸附性影响较弱。
A two-dimensional contaminant migration governing equation was established considering the waste degeneration,the non-linear adsorption characteristics of the compacted clay liners(CCL),the linear adsorption characteristics and the anisotropy of the aquitards and the aquifers and assuming that the lower part of the landfill should have three layers of soil,and the seepage field should be steady.The numerical analysis was carried out as regards some imaginary landfills.Through the computation and the analysis of change parameters,the contaminant concentration contours were obtained.The results indicate that the vertical hydrodynamic dispersion coefficient of CCL and the aquitards is the sensitive factor for the contaminant migration process.Only considering the non-linear adsorption characteristics of CCL,the combined parameter Sl,m is the sensitive factor for the contaminant migration.When the value of Sl,m is larger,the lateral migration ability of the contaminant increases,bu is not sensitive to adsorption intensity Kl,l.The effect of the linear adsorption of the aquitards on the contaminant migration is remarkable,that of the aquifes is weaker.