污染物在粗粒度多孔介质中的传输:采用多模型方法,使用先进的光谱分析
Jafar Chabokpour1, Hossein Hamidifar2
1Civil Engineering Department, University of Maragheh, Maragheh, Iran. j.chabokpour@maragheh.ac.ir.
Environmental geochemistry and health
|June 29, 2025
概括
在石床中污染物运输是复杂的,其中偏向占主导地位. 分数向导分散模型 (FADE) 最好预测溶液的运动,突出显示在粗介质中需要非Fickian模型.
科学领域:
- 环境科学 环境科学
- 水文地质学 水文地质学
- 地质化学 地质化学
背景情况:
- 了解粗粒多孔介质中的污染物运输对于管理环境风险至关重要.
- 传统模型往往难以捕捉河床等异质系统中溶液运动的复杂性.
研究的目的:
- 通过实验和计算来研究一维石床中的污染物运输.
- 为了比较三种不同的运输模型的性能:移动不移模型 (MIM),双孔模型 (DPM) 和分数向分散模型 (FADE).
- 确定关键的运输参数,并评估流量和度对污染物移动的影响.
主要方法:
- 进行了实验室实验,使用带有电导传感器的1D石床来监测突破曲线.
- 注射的化 (NaCl) 溶液在不同的度和流速.
- 应用MIM,DPM和FADE模型来分析实验数据并估计移动水分和质量转移系数等运输参数.
主要成果:
- 观察到偏向主导的传输 (高Péclet数),中介吸附以延迟因子表示.
- 分数向导分散模型 (FADE) 与MIM和DPM相比显示出更高的性能.
- 确定了流速加速和优选路径,分散系数通常随着深度的增加而下降.
结论:
- 粗粒度介质中的污染物运输是复杂的,并且经常表现出非Fickian行为.
- 准确的建模需要考虑非Fickian过程,而FADE显示出显著的前景.
- 结果为预测和管理自然和工程粗粒系统中的污染物运输提供了宝贵的见解.
相关概念视频
Porosity and Absorption of Aggregate
417
Aggregates contain pores of varying sizes; while some are completely enclosed within the particles, others open onto the surface, allowing water to penetrate. The porosity of aggregates is a major factor contributing to the overall porosity of concrete, given that aggregates constitute about three-quarters of concrete's volume.
When all pores in an aggregate are filled with water, the aggregate is considered saturated and surface-dry. If left in dry air, water will evaporate until the...
When all pores in an aggregate are filled with water, the aggregate is considered saturated and surface-dry. If left in dry air, water will evaporate until the...
417
Mechanistic Models: Compartment Models in Individual and Population Analysis
89
Mechanistic models are utilized in individual analysis using single-source data, but imperfections arise due to data collection errors, preventing perfect prediction of observed data. The mathematical equation involves known values (Xi), observed concentrations (Ci), measurement errors (εi), model parameters (ϕj), and the related function (ƒi) for i number of values. Different least-squares metrics quantify differences between predicted and observed values. The ordinary least...
89
Permeability of Concrete
221
Permeability in the context of concrete refers to how easily liquids or gases can pass through the material. This quality is crucial for assessing the water-tightness and durability of concrete structures and their resistance to chemical attacks. Concrete permeability can be determined through comparative laboratory tests. These tests typically involve sealing a concrete specimen from the sides, applying water pressure to the top surface with pressure, and measuring the amount of water passing...
221
Design Example: Analyzing Capacity Contours for Flood Risk Assessment
106
Flood risk assessment involves careful planning and analysis to ensure the safety of communities near water retention structures. Capacity contours are a vital tool in this process, as they illustrate the potential spread of water at specific levels in a given area. In the context of building a bund across a small valley, these contours play a critical role in evaluating the safety of nearby residential areas.In this example, the bund is intended to store stormwater in the valley. The engineers...
106
Porosity in Cement Paste
233
The porosity of concrete is a measure of the void spaces within its structure. These spaces impact its strength and durability significantly. When water and cement interact, a chemical reaction called hydration creates a semi-solid paste. This paste includes combined water, making up approximately 23% of the cement's dry mass, and gel water, which fills minuscule voids known as gel pores, accounting for about 28% of the cement gel volume.
The balance of water to cement in the mix is...
The balance of water to cement in the mix is...
233
Multicompartment Models: Overview
260
Multicompartment models are mathematical constructs that depict how drugs are distributed and eliminated within the body. They segment the body into several compartments, symbolizing various physiological or anatomical areas connected through drug transfer processes such as absorption, metabolism, distribution, and elimination.
These models offer a more comprehensive representation of drug behavior in the body than one-compartment models. They accommodate the complexity of drug distribution,...
These models offer a more comprehensive representation of drug behavior in the body than one-compartment models. They accommodate the complexity of drug distribution,...
260


