Abstract CO2 reinjection in petroleum reservoirs brings advantages in oil production but may cause dissolution in carbonate reservoirs. Two-scale continuum models have been successfully used to simulate acidification. However, the use of realistic porosity and permeability fields in mesh simulations is still a challenge, in such a way that uniform and normal distributions have been used to generate these fields in the past. The main objective of this work was to transcript the plugs heterogeneity from the micro-CT images to simulation. The porosity field was calculated directly from micro-CT images, and two methodologies are proposed to calculate the permeability field. A reactive two-scale continuum solver was implemented in OpenFOAM and used to simulate reactive flow in two carbonate samples with different intrinsic reaction rates (calcite and dolomite). The experimental permeability evolution curves, as well as wormholes shapes and paths, are reproduced in the simulations. We observed a critical influence of specific surface area, reaction rate constant, and initial permeability field for the simulations of acidification processes.

中文翻译：

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模拟具有真实孔隙度和渗透率场的碳酸盐岩反应流

摘要 CO2回注油藏具有采油优势，但可能会导致碳酸盐岩油藏溶解。两尺度连续模型已成功用于模拟酸化。然而，在网格模拟中使用真实的孔隙度和渗透率场仍然是一个挑战，过去曾使用均匀和正态分布来生成这些场。这项工作的主要目标是将插头异质性从显微 CT 图像转录到模拟。孔隙度场是直接从显微 CT 图像计算出来的，并提出了两种方法来计算渗透率场。在 OpenFOAM 中实现了反应性双尺度连续求解器，用于模拟具有不同固有反应速率（方解石和白云石）的两个碳酸盐样品中的反应流。模拟中再现了实验渗透率演化曲线以及虫洞形状和路径。我们观察到比表面积、反应速率常数和初始渗透场对酸化过程模拟的关键影响。