Numerical Simulation Study on Underground Gas Storage with Cushion Gas Partially Replaced with Carbon Dioxide

Carbon dioxide capture, use, and storage (CCUS) issues are currently gaining more attention due to climate change. One of the CCUS methods may be use CO2 as cushion gas in underground (UGS). Typically, high-permeability structures preferable for purposes. High permeability ensures good flow reservoirs well bottom-hole pressure maintenance. However, case a part gas, it mixes with natural within reservoir pore space, high permeability, resulting “ease flow”, can accelerate migration near-well zone. For this reason, analysis effect on content withdrawal overall performance UGS seems importance. In study, we used compositional numerical simulator evaluate effects not only but also structure type. The simulations covered depletion 10 cycles operation. Our results show that (and thus permeability) has great influence reservoir, mixing zone, gas.