WETTABILITY IMPACT ON CO2 STORAGE IN AQUIFERS: VISUALISATION AND QUANTIFICATION USING MICROMODEL TESTS,PORE NETWORK MODEL AND RESERVOIR SIMULATIONS

摘要

Wettability has been recognized as one of the controlling parameters of the remaining fluid saturations,capillary pressure and relative permeability curves;hence conditioning the performance of any CO2 injection process either for storage or IOR purposes.This paper presents an integrated study based on experimental and theoretical methods (micromodel tests and pore-network model respectively) and numerical simulations to evaluate in a comprehensive and robust manner,the impact of different wettability scenarios,at the core scale for CO2 injection in an aquifer.Some of the results observed in the micromodels were integrated in a pore network model in order to obtain capillary pressure and relative permeability curves,for various CO2/brine wettability conditions. Then,these curves and a compositional simulator dedicated to CO2 injection processes were used to quantify the impact of these different wettability scenarios on injectivity at the core scale and at the near wellbore scale.Using this approach,it is possible to investigate at a larger scale the effects of the wetting phenomena that are observed at the pore scale.Although the work presented in this manuscript does not include the main geological features(heterogeneities),the results obtained so far clearly demonstrate the importance of using reliable wettability data at reservoir conditions for the accuracy of the prediction of CO2 injection models at the reservoir scale.