Study on the universal scaling behavior of residual gas phases using micro-computed tomography

CO2气体的毛细捕集和随后的溶解是CCS(Carbon Capture Storage)技术的两个重要的存储过程，将在应用项目的框架内进行研究，中心目标是通过渗流理论预测的普遍标度定律来提升捕获气体团簇的孔尺度性质。首次用解析近似方法计算了有效溶出度，并用比较宏观模型(MIN3P和TOUGH2)进行了验证。最重要的问题是，在什么条件下，项目中研究的多孔介质属于同一普适性类别，以及孔结构、固体表面的微观结构和非均质润湿性对捕获过程的影响。基于团簇分析，我们将研究捕获气体团簇的几何形状和静态分布。捕获行为的动力学将通过玻璃球单分子膜内的光学可视化实验来研究。这些流体的选择是为了将其作为二氧化碳注入深层含水层的替代物。预期结果既具有基础性意义，又具有很大的实用意义，因为它们改进了CCS技术和地下水修复(溶解残留的NAPL(非水相液体)或混合气相)的预测模型。

The capillary trapping of CO2-gas and its subsequent dissolution are two important storage processes of CCS (Carbon Capture Storage) technology, which will be studied in the framework of the applied project.The central objective is an upscaling of pore-scale properties of trapped gas clusters by universal scaling laws predicted by percolation theory. For the first time, an analytical approximation method is used to calculate the effective dissolution rate and tested by comparative macroscale modeling (MIN3P and TOUGH2). Of fundamental interest is the question under which conditions the porous media studied within the project belong to the same universality class, and what is the influence of pore structure, microstructure of the solid surface and heterogeneous wettability on the trapping process.Methodically, the pore structure and the pore space topology will be analyzed and quantified using micro-computed tomography. Based on cluster analysis the geometry and the static distribution of trapped gas clusters will be studied. The dynamics of the trapping behavior will be investigated by optical visualization experiments within glass sphere monolayers. The fluids are selected so that they are proxies for CO2-injection into deep aquifers.The expected results are both of fundamental interest and of great practical relevance, as they improve predictive modeling for CCS-technology and for groundwater remediation (dissolution of residual NAPL (non aqueous phase liquid) or mixed gas phases).