Title : Geochemical analysis for safe implementation of CO2 storage in Lithuanian Reservoirs
Abstract:
Carbon Capture and Storage (CCS), plays a pivotal role in reducing the increasing CO2 emissions and addressing global warming. It achieves this by redirecting captured CO2 into subsurface geological formations for secure, long-term storage. However, the efficacy of this process relies heavily on understanding and managing the complex geochemical interactions that occur within the subsurface environment. These interactions encompass a range of chemical reactions and transformations that influence the behavior and fate of stored CO2, highlighting the need for thorough investigation and comprehension to ensure the effectiveness and safety of CCS initiatives.
Lithuanian reservoirs present great potential for carbon storage due to their considerable depth, petrophysical characteristics and storage capacity as discussed in published literatures. This study presents the importance of understanding the geochemical aspect of carbon storage in the subsurface reservoirs of Lithuania. CO2 injection experiments were conducted on rock samples from formations analogous to Lithuanian reservoirs. The rock samples were initially saturated with brine solutions and brine injection was performed. This was followed by the CO2 injection in liquid state into the rock samples. To understand the immediate impact of the CO2 injection, the brine solution was again injected into the rock samples. The permeability measurements were performed both pre and post CO2 injection resulting in a reduction in permeability post CO2 injection. Considering the dominant quartz mineralogy of Lithuanian reservoirs, which is recognized for its limited reactivity to CO2, this observation implies that mechanisms such as salt precipitation could exert a notable influence on permeability alterations. These findings highlight the intricate nature and the significance of understanding geochemical interactions and their impact on the safe, long-term storage of CO2.
Audience Takeaway Notes:
- Lithuanian reservoirs offer great potential for CO2 storage.
- Successful implementation of CO2 storage in subsurface reservoirs requires an insight into the CO2-brine-rock interaction.
- Salt precipitation could affect the CO2 injection by reducing permeability at the injection site.
- Quartz is predominantly unreactive with CO2.
