Geological carbon dioxide (CO₂) sequestration has been proposed as a viable technique to decrease effective emissions of CO₂ into the atmosphere. However, the security of this sequestration is tied to our understanding of the long‐term migration of CO₂ in subsurface. The dissolution of CO₂ in the reservoir brine is one of the main long‐term trapping mechanisms. However, the assumptions used in large‐scale reservoir simulations usually lead to an overestimation of the dissolution volume. We propose a modified approach based on the macroscopic invasion‐percolation (MIP) theory that allows the dissolution of CO₂ into brine. We used a high‐resolution geological model to compare the Darcy‐, modified MIP‐, and classic MIP‐based simulation results. We observed a significant shrinkage in the nonaqueous plume volume when dissolution is considered during the MIP simulation. In the case of Darcy‐based simulation, the plume was completely trapped inside the reservoir with limited migration even after a thousand‐year simulation. On the other hand, the majority of the plume migrated out of the simulated reservoir in the case of MIP. Our approach provides more realistic estimation of the dissolution volume and nonaqueous plume extent while leveraging the computational efficiency enjoyed by MIP. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd.

中文翻译：

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使用包括溶蚀作用的入侵渗流方法对二氧化碳羽流迁移进行建模

已经提出了隔离地质二氧化碳（CO ₂）作为减少向大气中有效排放CO ₂的可行技术。但是，这种隔离的安全性取决于我们对地下CO ₂长期迁移的理解。CO ₂在储层盐水中的溶解是主要的长期捕集机制之一。但是，大型储层模拟中使用的假设通常会导致对溶出量的高估。我们基于宏观入侵渗滤（MIP）理论提出了一种改进的方法，该方法可以溶解CO ₂放入盐水。我们使用了高分辨率的地质模型来比较Darcy，修改后的MIP和经典的基于MIP的模拟结果。当在MIP模拟过程中考虑溶解时，我们观察到非水羽流体积明显收缩。在基于Darcy的模拟中，即使经过一千年的模拟，羽流也完全被困在了储层内部，而迁移却受到限制。另一方面，在MIP的情况下，大部分羽流从模拟油藏中迁移出来。我们的方法在利用MIP享有的计算效率的同时，提供了对溶出量和非水羽流程度的更现实的估计。©2020年化学工业协会和John Wiley＆Sons，Ltd.