The capabilities of reactive transport modeling codes for geological carbon sequestration have improved significantly in the past decade. Comparing different geochemical modeling codes is crucial to identify modeling discrepancies, especially when experimental validation is not feasible. However, it is challenging to consistently get comparable results, as shown in previous studies where batch reaction of CO₂ storage using different simulators sometimes resulted in significant discrepancies in their outputs. In this study, we introduce and demonstrate an approach to consistently produce comparable batch-reaction modeling of kinetically controlled CO₂-water-rock interactions in PHREEQC, TOUGHREACT, and GEM, which are amongst the most widely used simulators for CO₂ sequestration studies. The primary step is to assemble a thermodynamic database in PHREEQC format, with representative fluid properties for CO₂-water interaction, and carefully convert it to the format of the other simulators. We use two case studies from the literature to demonstrate our method where good matches between the outputs of all three simulators were achieved, which was not previously attained. Furthermore, limiting the discrepancies in batch-reaction models provides a consistent baseline to study the coupled mechanisms of transport and chemical reaction, which was also successfully demonstrated with a one-dimensional reactive transport model in PHREEQC, GEM and TOUGHREACT.

在过去十年中，用于地质碳封存的反应输运建模代码的能力得到了显着提高。比较不同的地球化学建模代码对于识别建模差异至关重要，尤其是在实验验证不可行的情况下。然而，始终获得可比较的结果是具有挑战性的，如先前的研究所示，其中使用不同模拟器的 CO ₂储存的批量反应有时会导致其输出的显着差异。在本研究中，我们介绍并演示了一种方法，该方法可在 PHREEQC、TOUGHREACT 和 GEM 中持续生成动力学控制的 CO _{2 -}水-岩石相互作用的可比批反应建模，这些都是最广泛使用的 CO ₂模拟器封存研究。首要步骤是组装一个 PHREEQC 格式的热力学数据库，具有 CO _{2 -}水相互作用的代表性流体特性，并小心地将其转换为其他模拟器的格式。我们使用文献中的两个案例研究来演示我们的方法，其中实现了所有三个模拟器的输出之间的良好匹配，这是以前没有实现的。此外，限制批量反应模型中的差异为研究传输和化学反应的耦合机制提供了一致的基线，这也在 PHREEQC、GEM 和 TOUGHREACT 中的一维反应传输模型中得到了成功证明。