Bacterial transport in porous media: Evaluation of a model using laboratory observations
Bacterial transport in porous media: Evaluation of a model using laboratory observations
复制标题
多孔介质中的细菌传输：使用实验室观察评估模型
DOI：
10.1029/91wr02980
复制
发表时间：
1992
影响因子：
5.4
通讯作者：
J. Herman
中科院分区：
文献类型：
--
作者：
G. Hornberger;A. Mills;J. Herman
控制细菌通过多孔介质的运输的因素尚不清楚。分散过程的相对重要性，细菌细胞通过各种机制的固定（沉积），以及随后释放这些被困细胞（夹带）在描述运输中尚未得到实验的阐明。此外，用于模拟这些过程的现象学系数的可变性是未知的，因为这些主要因素如颗粒大小、生物体和水的离子强度发生了变化。我们报告了用两种尺寸的沙子、两种离子强度的载体溶液和两种不同尺寸的生物，将平流-弥散方程的解拟合到填充砂柱的突破曲线的结果，该方程经过修改以考虑沉积和夹带。平流-色散方程的解包括三个过程，即弥散、沉积和夹带，它提供的数据匹配优于忽略其中一个过程的解。描述沉积的系数的拟合值与控制变量（生物体、晶粒尺寸和离子强度）的变化一致，并且通常在理论预测的一个数量级内。
The factors that control the transport of bacteria through porous media are not well understood. The relative importance of the processes of dispersion, of immobilization of bacterial cells by various mechanisms (deposition), and of subsequent release of these trapped cells (entrainment) in describing transport has not been elucidated experimentally. Moreover, the variability of the phenomenological coefficients used to model these processes, given changes in such primary factors as grain size, organism, and ionic strength of the water, is unknown. We report results of fitting solutions of an advection-dispersion equation, modified to account for deposition and entrainment, to breakthrough curves from packed sand columns using two sizes of sand, two ionic strengths of the carrier solution, and two organisms with different sizes. A solution to the advection-dispersion equation including three processes, that is, dispersion, deposition, and entrainment, provides a match to the data that is superior to that achieved by solutions ignoring one of the processes. Fitted values of the coefficient describing deposition vary in a consistent manner with the control variables (organism, grain size, and ionic strength) and are generally within one order of magnitude of those predicted on the basis of theory.