Assessing the potential for CO2 storage in saline aquifers in Brazil: Challenges and Opportunities

This study underscores the critical role of carbon capture and storage (CCS) in mitigating greenhouse gas emissions and addresses the potential for CCS projects in saline aquifers in Brazil, one of the world's largest carbon emitters. The country's ability to adopt CCS is significantly influenced by the availability of data related to regional CO2 storage potential and identifying suitable geological framework for CO2 injection. While oil and gas reservoirs have traditionally been prioritized, saline aquifers represent an underexplored and potentially higher capacity storage option. Despite Brazil's 31 sedimentary basins, the data quantity and availability for these contexts remain insufficient for advanced studies on the geological storage of CO2 considering saline aquifers. An initial study was conducted indicating five potential targets in the Paraná and Potiguar Basins for geological storage in saline aquifers based on available public data, mainly drilling data. This review reveals substantial challenges related to the evaluation of Brazil's CO2 storage capacity, such as the lack of modern seismic studies, the absence of a regulatory framework for CO2 storage, and insufficient investment in new well exploration. These challenges necessitate multistakeholder collaboration, the development of a supportive regulatory environment, and investment in extensive site characterization campaigns. Addressing these barriers is fundamental to realizing the country's CCS potential and contributing to global decarbonization efforts. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd.