Carbon dioxide (CO₂) sequestration in deep shale reservoirs with enhanced shale gas methane (CH₄) recovery contributes to both CH₄ recovery and CO₂ emission mitigation. In this work, the adsorption behaviors of pure CH₄ and CO₂ on shales, and the displacement behaviors of CH₄ adsorbed on shales by CO₂ injection were investigated. The single component adsorption indicates that the simplified Ono-Kondo lattice model can well describe both CH₄ and CO₂ adsorption on shales. The maximum adsorption capacity of CH₄ obtained from the simplified Ono-Kondo lattice model shows significant linear correlation with the micropore parameters of shales, while this linear correlation is weak for CO₂. The investigation on the displacement behaviors based on the improved experimental procedure and data processing method raised in this work confirms that CH₄ adsorbed on shales can be displaced by CO₂, which provides the experimental evidence for the feasibility of CO₂ sequestration in shale reservoirs with enhanced CH₄ recovery. The amounts of recovered CH₄ and stored CO₂ increase with CO₂ injection pressure. The recovery yield of CH₄ due to CO₂ injection is higher for shales with smaller micropore parameters or lower adsorption performance. The microscopic mechanism of the displacement process is strongly related to the injection pressure of CO₂. Based on the conceptual model established for the process of CH₄ adsorbed on shales displaced by CO₂ injection, it is recommended to inject CO₂ after partial desorption of CH₄, which can improve CH₄ recovery and CO₂ sequestration of the target shale reservoirs.

页岩气中甲烷（CH ₄）回收率提高的深层页岩储层中的二氧化碳（CO ₂）螯合有助于CH ₄回收率和CO ₂排放缓解。在这项工作中，研究了纯CH ₄和CO ₂在页岩上的吸附行为，以及通过注入CO ₂吸附在页岩上的CH ₄的置换行为。单组分吸附表明简化的Ono-Kondo晶格模型可以很好地描述页岩上的CH ₄和CO ₂吸附。CH ₄的最大吸附量从简化的Ono-Kondo晶格模型获得的结果显示与页岩的微孔参数具有显着的线性相关性，而对于CO ₂，这种线性相关性较弱。通过改进的实验程序和数据处理方法对驱替行为的研究证实了页岩中吸附的CH ₄可以被CO ₂驱替，这为CO ₂螯合在页岩油藏中的可行性提供了实验证据。增强了CH _4的回收率。CH ₄的回收量和CO _2的储存量随着CO ₂注入压力而增加。CH ₄的回收率对于细孔参数较小或吸附性能较低的页岩，由于注入CO ₂的影响较高。驱替过程的微观机理与CO ₂的注入压力密切相关。基于用于CH的过程中建立的概念模型₄吸附在由CO移位页岩₂喷射，建议注入CO ₂ CH的局部解吸后₄，这样可以提高CH ₄回收和CO ₂的目标页岩储层的隔离。