The French PICOR Project on the Storage of CO₂ in Geological Reservoirs: Experimental Work and Numerical Simulations on Gas-Water-Rock Interaction

 

Brosse, Etienne, Institut Français du Pétrole, Rueil-Malmaison, France

 

The PICOR project (2001 – 2004) addressed the various phenomenological aspects involved by the storage of CO₂ in permeable sediments, either deep saline aquifers or depleted hydrocarbon fields : (1) thermodynamic fluid-phase behaviour and solubility of CO₂ in oil or brine ; (2) polyphasic displacements during injection, close to the injection wells or at the formation scale ; (3) interaction between water acidified by dissolved CO2 and minerals. A combination of experimental work and modelling approaches was used.

Gas-water-rock interaction in the specific context of CO₂ storage was investigated in PICOR by a variety of studies that will be briefly described during the presentation :

the measurement of dissolution rates of mineral carbonates in presence of high partialpressures of CO₂ (pCO₂) values (Pokrovsky and Schott, 2005) ;

plug-flow experiments in carbonate rocks, with a monitoring of the pore-space evolu-tion using synchrotron microtomography (Noiriel et al., 2005) ;

    the measurement of pressure-solution creep rate in limestones, enhanced by highp CO₂ values ;

    the calibration, from plug-flow experiments, of petrophysical parameters included inreaction-transport numerical models (Brosse et al., 2005) ;

    the development of a modelling tool to calculate the effect of pCO₂ on pressure-solu-tion creep rate in limestones (Renard et al., 2005) ;

    evaluation of the impact of a precise calculation of CO₂ solubility in brines on the reac-tivity of a water-rock system at the formation scale, using geochemical models (Kervévan et al., 2005).