Influence of geochemical processes on the geomechanical response of the overburden due to CO2 storage in saline aquifers

Abstract

a b s t r a c tThe objective of the study is to investigate the influence of geochemical processes on the geomechanical response of overburden during and after CO 2 injection. In the current study, coupled multiphase fluid flow and geomechanical modeling with geochemical processes were performed to simulate large-scale injection of CO 2 (up to 10 million metric tonnes per year) into a deep saline aquifer over the long-term (up to 1000 years). The geochemical modeling results show that geochemical processes, such as mineral dissolution and precipitation, do not have a significant influence on reservoir rock porosity (about 2% reduction). Modeling results show that the inclusion of geochemical reactions in the coupled fluid flow and geomechanical models do not have any significant influence on the computed pressure and ground displacements due to CO 2 injection for the typical mineralogical composition considered in this study. In other words, a coupled single-phase fluid flow and geomechanical model would give similar results at a significantly lower computational effort.

Impact of geochemical and geomechanical changes on CO2 sequestration potential in sandstone and limestone aquifers

“…Looking at these figures, it was observed that at the end of the injection periods in both aquifers, ground displacement is quantitatively different but very high near the wellbore region due to the pressure buildup as highlighted by Shi et al 12 As time passes and in the postinjection period, there is a continuous decline in the ground displacement, which is more pronounced in limestone. This contradicts the finding presented by Varre et al 2 where it was highlighted that calcite has an insignificant influence on the geochemical activity and vertical ground displacement of limestone. Likewise, another study by Hangx et al 52 showed the complete dissolution of calcite in sandstone upon chemical interaction of CO 2 without any effect on the mechanical properties.…”

“…The magnitude of vertical displacement obtained for the sandstone in this study is aligned with the results presented by Varre et al,2 where a sandstone formation with 76% quartz was simulated for 200 years. For the limestone aquifer, on the other hand, the results obtained were very close to what was reported by Kim et al50 and Masoudi et al, …”

“…1 Deep saline aquifers have been recognized as the most suitable CO 2 storage sites worldwide. 2 These aquifers, which are mainly composed of sandstone or carbonate rocks, can properly entrap CO 2 by favorable chemical interactions. However, these interactions, which often lead to geomechanical changes and in situ stress alterations, pose integrity issues in the CCS sites.…”

Experimental Study of CO2-Water-Mineral Interactions and Their Influence on the Permeability of Coking Coal and Implications for CO2-ECBM

“…HCO 3 -combined with positive ion in water solution as shown in Equations (7) and (8). Subsequently, bicarbonate and carbonate ions collided with divalent cation, they formed carbonate (Equations (9)(10)(11)(12) …”

“…Fluid seepage mainly occurs through natural cleats or fractures, the interaction of minerals with CO 2 and groundwater significantly affects the flow characteristics of coal reservoirs [10]. Various studies on the mechanism of CO 2 -water-rock interactions have been conducted [11][12][13][14], the role of acidification to rock minerals through CO 2 injection, with the huge potential for CO 2 storage, was identified in saline aquifers and depleted oil and gas reservoirs. Considering its successful use in the oil and gas extraction industry, the acidizing approach was utilized for CBM recovery.…”