Carbon capture and storage (CCS) would contribute considerably towards climate change mitigation, if it would be implemented on a very large scale; at many storage sites with substantial injection rates. Achieving high injection rates in deep saline aquifers requires a detailed assessment of injectivity performance and evaluation of the processes that alter the permeability of the near-well region. One of the most common forms of the injectivity loss in the context of CO₂ storage in saline aquifers is salt precipitation driven by the evaporation of brine into the relatively dry injected CO₂ stream. We present a novel compositional transport formulation based on overall-composition variables which models salt as a separate solid phase which could potentially form through two essentially different ways, i.e., kinetic or equilibrium. To model formation drying-out and subsequent halite-precipitation, an accurate and reliable fluid model ePC-SAFT, which can effectively account for ionic effects, is applied. In addition, a volume balance approach (i.e., depending on how far the salt saturation is from the solubility limit) is implemented to estimate solid saturation in a simulation cell. The resulting simulator is benchmarked against several well-known examples, with analytical solutions demonstrating the ability of the code to cover a variety of physical mechanisms. Finally, injection of dry CO₂ into a brine-saturated core-scale domain is simulated and sensitivity analyses over various parameters are performed. We show that the new model is capable to quantitatively represent the physics of salt precipitation (for example salt self-enhancing) under different reservoir conditions.

如果碳捕集与封存（CCS）得以大规模实施，它将为缓解气候变化做出巨大贡献；在许多具有大量注入速率的存储地点。要在深层盐水中获得高注入速率，就需要对注入性能进行详细评估，并对改变近井区渗透率的过程进行评估。在盐水层中CO ₂储存的情况下，注入性损失的最常见形式之一是盐分的沉淀，这是由盐水蒸发成相对干燥的注入的CO _2驱动的流。我们提出了一种基于整体组成变量的新型组成传输公式，该模型将盐建模为单独的固相，可以通过两种基本不同的方式（即动力学或平衡）形成盐。为了模拟地层干燥和随后的岩盐沉淀，应用了可以有效考虑离子效应的准确可靠的流体模型ePC-SAFT。此外，采用数量平衡的方法（即，取决于盐饱和度与溶解度极限的距离）来估算模拟单元中的固体饱和度。生成的模拟器针对多个著名示例进行了基准测试，分析解决方案证明了代码涵盖各种物理机制的能力。最后，模拟了将干燥的CO ₂注入饱和盐水的岩心规模区域，并对各种参数进行了敏感性分析。我们表明，新模型能够定量表示不同储层条件下盐析出的物理现象（例如盐的自我增强）。