The Importance of De-Watering Before Storing Carbon Dioxide in Saline Aquifer

Abstract This paper discusses the important need for creating voidage before carbon dioxide storage in saline aquifers. We show how creating voidage within the aquifer has the potential to significantly increase the overall capacity for CO2 storage. We demonstrate how the voidage can help in accommodating larger volumes of CO2, making the storage process more efficient and effective. The paper includes the results of computations to ensure the storage sites do not add an environmental concern from high-pressure gradients that can be generated without dewatering. In the computational and modeling work, we considered various aquifer sizes and different depths for a saline aquifer that could be considered for permanent carbon dioxide storage. In our detailed modeling, we also considered the case of no voidage generation. Furthermore, we addressed various desalination options for handling produced brine. By creating voidage, or lowering pressure, within the aquifer, there is potential to increase the overall capacity for CO2 storage. This can help in accommodating larger volumes of CO2, making the storage process more efficient and effective. Introducing CO2 into a saline aquifer increases the pressure within that geological formation. We show how creating voidage can help alleviate the net pressure increases, reducing the risk of leakage or other structural failures in subsurface geological containment. The results show voidage creation can facilitate the movement and distribution of CO2 throughout the saline aquifer. CO2 can more easily infiltrate porous rock formations by creating pathways, ensuring more uniform and effective storage. Furthermore, voidage can also make it easier to monitor CO2 storage sites. We examined noted more effective tracking of CO2 movement that ensures secure storage in the intended geological formations without migrating to unintended areas. By managing the voidage and internal pressure, we show how to mitigate the risk of caprock failure, thus enhancing both the safety and permanence of the CO2 storage solution. Our results show how creating voidage must be performed carefully to ensure maintain the geological integrity of the aquifer. The paper demonstrates how creating voidage before CO2 storage in saline aquifers is essential for maximizing capacity, ensuring safety, maintaining pressure, enhancing fluid dynamics, and preserving geological integrity.