Yan Zhu, Ziteng Cui, Kun Li, Chaoqi Wang, Zhao Li, Xueyi Zhang, Zhi Dou
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引用次数: 0
Abstract
Adsorption reaction in unsaturated porous media is of great importance for soil and groundwater remediation. In this study, the influence of the Peclet number (Pe) and water saturation on adsorption behavior at liquid-liquid interfaces was quantitatively investigated. The pore-scale reactive transport in unsaturated porous media was directly simulated. The Navier-Stokes equations, the surface transfer and adsorption reaction equations, and the advection-diffusion equation (ADE) were coupled to obtain the flow and concentration fields. The results showed that water saturation had a significant influence on the complexity of the flow field. A nonmonotonic relationship was found between water saturation and the uniformity of the flow field. Peclet number had little influence on the maximum adsorption. On the other hand, the adsorption time showed a nearly linear relationship with the Peclet number and increased with increasing Peclet number. Additionally, a nonlinear relationship was found between water saturation and the maximum adsorption. As water saturation increased, the maximum adsorption tended to increase to a peak and then decrease. The peak of the maximum adsorption occurred at , , and the shortest adsorption time was observed at . However, the difference in adsorption times for saturations of 0.458 and 0.698 was not significant and was only about 20 PV difference.
非饱和多孔介质中的吸附反应对土壤和地下水的修复具有重要意义。在本研究中,定量研究了Peclet数(Pe)和水饱和度对液-液界面吸附行为的影响。直接模拟了非饱和多孔介质中孔隙尺度的反应输运过程。将Navier-Stokes方程、表面转移和吸附反应方程、平流扩散方程(ADE)耦合得到了流动场和浓度场。结果表明,含水饱和度对流场的复杂程度有显著影响。发现含水饱和度与流场均匀性之间存在非单调关系。Peclet数对最大吸附量影响不大。另一方面,吸附时间与Peclet数呈近似线性关系,并随着Peclet数的增加而增加。此外,含水饱和度与最大吸附量之间存在非线性关系。随着含水饱和度的增加,最大吸附量呈先增大后减小的趋势。最大吸附峰出现在Pe = 5, S w = 0.458, S w = 0.902时吸附时间最短。而饱和度0.458和0.698的吸附次数差异不显著,仅相差约20 PV。
期刊介绍:
Geofluids is a peer-reviewed, Open Access journal that provides a forum for original research and reviews relating to the role of fluids in mineralogical, chemical, and structural evolution of the Earth’s crust. Its explicit aim is to disseminate ideas across the range of sub-disciplines in which Geofluids research is carried out. To this end, authors are encouraged to stress the transdisciplinary relevance and international ramifications of their research. Authors are also encouraged to make their work as accessible as possible to readers from other sub-disciplines.
Geofluids emphasizes chemical, microbial, and physical aspects of subsurface fluids throughout the Earth’s crust. Geofluids spans studies of groundwater, terrestrial or submarine geothermal fluids, basinal brines, petroleum, metamorphic waters or magmatic fluids.