CO2 sequestration and EOR cooptimization in a mature field: Teapot Dome, Wyoming.

摘要

CO2 Enhanced Oil Recovery (CO2-EOR) has been a mature technology for more than 40 years. This EOR process offers opportunities to mitigate CO2 emissions through co-optimization of CO2 sequestration and EOR. In this thesis, we focus on the Tensleep Sandstone to simulate CO2-EOR and sequestration, and analyzed the effect of different injection scenarios.;Research has been conducted to study mechanisms in CO2-EOR and CO2-sequestration, respectively. CO2-EOR mechanisms in the simulation included CO2 dissolution in crude oil to decrease viscosity and swelling crude oil. For CO2 sequestration, CO 2 was allowed to get trapped in the pore space by hysteresis effects and dissolved in formation water through solubility. Based on a geostatistical model with detailed information on the reservoir geology, a dynamic model was built using the compositional simulator CMG-GEM. Simulation results for CO2-EOR and sequestration in Tensleep B sandstone will serve future economic evaluations and reservoir development design. The sequence of injection influences oil recovery; the best timing for CO2 injection to obtain a maximum oil recovery is the beginning of reservoir exploitation. When it comes to CO2 sequestration, the best timing of CO2 injection leading to the maximum storage volume is after continuous water injection. For water-alternating-gas scenarios, six month cycles are recommend, based on the high oil recovery observed and perceived lower operating cost.