Numerical simulation of fluid flow, transport, and trapping mechanisms have been used to optimize CO₂ storage in geologic formations by improving trapping efficiency through injection strategies. Flow models, however, do not capture the geomechanical deformation that can occur during CO₂ injection, including reservoir expansion, ground surface uplift, and induced seismicity. The geomechanical risks of CO₂ injection have drawn more attention in recent years and coupled flow and geomechanical simulation models are increasingly used to study the geomechanical effects during CO₂ injection, to ensure environmentally sound and safe operations. We present an optimization framework for geologic CO₂ storage under geomechanical risks, where coupled flow-geomechanics simulations are used to quantify the risks of injection-induced ground surface deformation and rock failure in reservoir and caprock layers. A multi-objective optimization problem is formulated and solved to maximize CO₂ storage while minimizing the two forms of geomechanical risks. The optimization decision variables include the locations of injection wells. Multiple numerical experiments with increasing complexity are presented to demonstrate the performance of the proposed framework. The results reveal optimal decisions that are different from those obtained from flow-only simulation that disregard the geomechanical risks associated with CO₂ injection. When geomechanical risks are considered, the wells may not necessarily be concentrated in areas with the highest storage capacity because that may lead to rock failure and/or unacceptable levels of ground surface uplift. Overall, the observations from this study reveal important differences in optimization results and conclusions when geomechanical risks of geologic CO₂ storage are considered.

流体流动、传输和捕集机制的数值模拟已被用于通过注入策略提高捕集效率来优化地质地层中的CO ₂储存。然而，流动模型没有捕捉到 CO ₂注入过程中可能发生的地质力学变形，包括储层膨胀、地表隆起和诱发地震活动。近年来，CO ₂注入的地质力学风险越来越受到关注，耦合流和地质力学模拟模型越来越多地用于研究CO ₂注入过程中的地质力学效应，以确保环境无害化和安全运营。我们提出了地质 CO ₂的优化框架地质力学风险下的储存，其中耦合流动地质力学模拟用于量化注入引起的地表变形和储层和盖层中岩石破坏的风险。制定并解决了多目标优化问题，以最大限度地提高 CO ₂储存量，同时最大限度地减少两种形式的地质力学风险。优化决策变量包括注入井的位置。提出了复杂性不断增加的多个数值实验，以证明所提出框架的性能。结果揭示了与从仅流动模拟中获得的决策不同的最佳决策，后者忽略了与 CO ₂相关的地质力学风险注射。当考虑地质力学风险时，井可能不一定集中在具有最高存储容量的区域，因为这可能导致岩石破裂和/或不可接受的地表隆起水平。总的来说，当考虑地质 CO ₂封存的地质力学风险时，本研究的观察结果揭示了优化结果和结论的重要差异。