Three-Dimensional Model for Subsurface Transport and Biodegradation
Three-Dimensional Model for Subsurface Transport and Biodegradation
复制标题
地下传输和生物降解的三维模型
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
Mark A. Widdowson
中科院分区：
文献类型：
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作者：
D. Waddill;Mark A. Widdowson
本文描述并论证了一个具有好氧和顺序厌氧生物降解的地下溶质运输的数值模型。该模型可以在三维、各向异性、非均质域内描述多个组分。烃类污染物被模拟为微生物生长的电子供体，可用的电子受体（EAs）可以同时或按以下顺序利用：O{sub 2}、NO{sub 3}{sup{负}}、Mn（IV）、Fe（III）、SO{sub 4}{sup 2{负}}和CO{sub 2}。该模型可以将Mn（II）、Fe（II）、H{sub w}S、CH{sub 4}和用户定义的氮化合物作为生物降解的产物。每个碳氢化合物底物的生物降解遵循Monod动力学，修改包括EA和养分有效性的影响。抑制功能允许任何EA抑制所有其他为微生物提供较少能量的EA的利用。微生物生物量被定义为附着在多孔介质上的分散的微菌落。该模型假设相间扩散对微生物生长的限制可以忽略不计，并且没有分配给菌落的几何参数。模型的行为使用简单的、假设的测试用例来演示。将生物可降解碳氢化合物的运输与非生物可降解示踪剂在三维假想区域进行比较。厌氧生物降解显著降低了预测的污染物浓度和传播距离。总的污染物质量的生物降解取决于EA的有效性，不遵循一级动力学。«少
This paper describes and demonstrates a numerical model for subsurface solute transport with aerobic and sequential anaerobic biodegradation. The model can depict multiple constituents in a three-dimensional (3D), anisotropic, heterogeneous domain. Hydrocarbon contaminants are simulated as electron donors for microbial growth, and available electron acceptors (EAs) may be utilized simultaneously or in the following sequence: O{sub 2}, NO{sub 3}{sup {minus}}, Mn(IV), Fe(III), SO{sub 4}{sup 2{minus}}, and CO{sub 2}. The model can account for Mn(II), Fe(II), H{sub w}S, CH{sub 4}, and a user-defined nitrogenous compound as products of biodegradation. Biodegradation of each hydrocarbon substrate follows Monod kinetics, modified to include the effects of EA and nutrient availability. Inhibition functions allow any EA to inhibit the utilization of all other EAs that provide less energy to the microbes. Microbial biomass is conceptualized as scattered microcolonies attached to the porous medium. The model assumes that interphase diffusion limitations to microbial growth are negligible and no geometrical parameters are assigned to the colonies. The behavior of the model was demonstrated using simple, hypothetical test cases. Transport of a biodegradable hydrocarbon was compared to a nonbiodegradable tracer in a 3D, hypothetical domain. Anaerobic biodecay significantly reduced predicted contaminant concentrations and travel distance. Biodegradation of themore » total contaminant mass depends on EA availability and did not follow first-order kinetics.« less