基于图像法的多孔介质双分子反应溶质运移模拟

采用图像分析法确定溶质浓度,以硫酸铜和EDTA二钠作为双分子反应物,在多孔介质模型中开展了不同粒径(1.52.0,2.53.0,3.54.0 mm)和流量(1.0,1.5,2.0 mL/s)下反应性溶质运移实验,探讨了应用不完全混合的对流弥散模型(IM-ADRE)对双分子反应溶质运移的模拟和预测,并进行了参数敏感性分析。结果表明:图像分析法可准确获取多孔介质中显色反应性溶质的浓度,灰度值与浓度的决定系数R²大于0.96;用IM-ADRE模型能够准确预测双分子反应性溶质硫酸铜和EDTA二钠在3种不同多孔介质中的运移过程,误差低于3.71%;实验条件的改变对IM-ADRE模型参数D、m和β₀的影响显著,说明模型参数依赖于环境条件,其变化规律需要根据实际环境条件进一步率定,便于IM-ADRE模型的进一步推广应用。

Simulation of bimolecular reactive solute transport in porous media via image analysis

In this study, reactive solute transport experiments in porous media were carried out under different particle sizes (ϕ1.5-2.0, 2.5-3.0, and 3.5-4.0 mm) and flow rates (1.0, 1.5, and 2.0 mL/s). We used copper sulfate and disodium EDTA as bimolecular reactors and simulated their transport via image analysis. The incomplete mixing advection-dispersion reaction equation (IM-ADRE) based simulation and prediction of bimolecular reactive solute transport was investigated, and parameter sensitivity analysis was performed. The results showed that the concentration of color reactive solutes in porous media can be accurately obtained via image analysis. The determination coefficient between the gray value and concentration was greater than 0.96. The IM-ADRE model gave high accuracy predictions for bimolecular reactive solute transport in porous media under different conditions, with less than 3.71% relative errors. The change of experimental conditions had significant effects on parameters D, M and β₀ of IM-ADRE model, indicating that the model parameters are dependent on the environmental conditions, and the dependency rules need to be further calibrated according to actual environmental conditions, which can help promoting IM-ADRE model applications.