考虑降解时双层介质中有机污染物的一维扩散解析解  

Analytical solutions for contaminant diffusion in two-layered porous media considering degradation

作　　者：谢海建[1,2] 蒋元生[1] 杨文参[1] 陈云敏[2] 

机构地区：[1]浙江大学水文与水资源工程研究所,浙江杭州310058 [2]浙江大学软弱土与环境土工教育部重点实验室,浙江杭州310058

出　　处：《岩土工程学报》2013年第S1期190-196,共7页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(51278452;51008274;51010008);973计划项目(2012CB719806);浙江省公益性技术研究项目(2011C21061);浙江省自然科学基金项目(LYBD060003)

摘　　要：有机污染物往往比无机物离子对环境有更大的危害。为了研究填埋场有机污染物在衬垫系统的运移规律,建立了有机污染物在双层多孔介质中的一维扩散模型,同时考虑有机污染物在介质中的降解作用。针对零浓度和零通量两种下边界条件,推导出模型的解析解。与数值模型POLLUTE v7的比较说明了本文模型的合理性和有效性。基于得到的解析解,分析了降解作用对有机污染物在成层介质中的运移影响与相关参数的敏感性。结果表明有机污染物的降解作用能有效地减少有机污染物在土壤衬垫系统中的浓度分布和底部通量。当土层降解半衰期为5～10 a时,底部污染物通量可比不考虑降解时减少4～8倍。相对于下层土,上层土降解作用对提高整体的防污性能更有效,能更显著地降低污染物的浓度。The organic contaminants are always more harmful to the environment than the inorganic ions.One-dimensional mathematical model for organic contaminant diffusion through two-layered porous media is developed to investigate the behavior of organic transport in the landfill liner system.Degradation of the organic contaminants in the porous media is considered.The bottom boundary conditions are assumed to be zero concentration or zero flux.The analytical solutions for the mathematical model are obtained by means of the method of separation of variables.The results obtained by the proposed analytical solution agree well with those obtained by the commercial software POLLUTE v7.The effect of degradation on organic contaminant diffusion through the layered media is investigated on the basis of the proposed solutions.The bottom concentration and flux of the soil liners can be greatly reduced when the degradation effect is considered.The bottom flux for the liner system with the half-lives of 5-10 years can be 4-8 times less than those assuming no degradation.Compared to that of the lower layer,the effect of the degradation of the upper layer is more important on reducing the organic concentration in the underlying environment.

关 键 词：有机污染物 双层多孔介质 解析解 扩散 降解 填埋场 

分 类 号：X13[环境科学与工程—环境科学]