Hysteresis effects in geological CO2 sequestration processes： A case study on Aneth demonstration site, Utah, USA

摘要

Realistic models for saturation, capillary pressure and relative permeability s-p_c-kr relations are essential for accurate predictions in multiphase flow simulations. The primary object of this work is to investigate their influence on geological CO_2 sequestration processes. In this work, the hysteresis effects on simulation results predicting geological CO_2 storage are investigated on a synthetic 2D model and a geological setting built according to Aneth demonstration site. Simulation results showed that hysteretic relative permeability model should be included while the residual trapping mechanism is under investigation. The effects of hysteresis and WAG schemes were studied with a series of numerical simulations on a geological setting based on Aneth site. Our simulations demonstrate that the hysteresis effect is strong on residual trapping mechanisms and there is no significant effects of alternative WAG schemes for long term residual trapping in our conceptual model. The effects of WAG schemes and hysteresis are weak on dissolution trapping mechanisms.