GEOCHEMICAL INTERACTIONS BETWEEN CO_2, PORE-WATERS AND RESERVOIR ROCKS

摘要

The degree of reactivity between COj, pore-waters and minerals may have significant consequences on CO2 storage capacity, the injection process, and long-term safety and stability. Geochemical reactions are highly site-specific and time-dependent. They need to be assessed on a site-to-site basis according to best practises by combining numerical modelling and observations from laboratory experiments, field monitoring, and natural analogues. A selection of lessons learned from three European projects about the reactivity of CO2 with reservoir rocks and cap rocks is presented here for three sites: Sleipner (Norway) and Weyburn (Canada) where more than 1 Mt of CO2 per year has been injected underground since 1996 and 2000 respectively, and Montmiral, a natural CO2 field in France.