AUTHOR=Kelemen Peter , Benson Sally M. , Pilorgé Hélène , Psarras Peter , Wilcox Jennifer TITLE=An Overview of the Status and Challenges of CO2 Storage in Minerals and Geological Formations JOURNAL=Frontiers in Climate VOLUME=1 YEAR=2019 URL=https://www.frontiersin.org/journals/climate/articles/10.3389/fclim.2019.00009 DOI=10.3389/fclim.2019.00009 ISSN=2624-9553 ABSTRACT=

Since the Industrial Revolution, anthropogenic carbon dioxide (CO₂) emissions have grown exponentially, accumulating in the atmosphere and leading to global warming. According to the IPCC (IPCC Special Report, 2018), atmospheric warming should be <2°C to avoid the most serious consequences associated with climate change. This goal may be achieved in part by reducing CO₂ emissions, together with capturing and sequestering CO₂ from point sources. The most mature storage technique is sequestration in deep saline aquifers. In addition, CO₂ can be mineralized and sequestered in solid form by various techniques, i.e., ex-situ, surficial and in situ mineralization. Ex situ and surficial approaches may produce valuable products while mitigating environmental hazards. In-situ mineralization uses ultramafic and mafic geological formations for permanent, solid storage. In addition, the IPCC portfolio that limits warming to <2°C by 2100 includes avoiding CO₂ emissions and removal of CO₂ from air. Regardless of the specific mix of approaches, it will be essential to permanently sequester about 10 billion tons of CO₂ per year by mid-century, and roughly twice that amount each year by 2100. Maximizing the potential of technologies for CO₂ removal from air and CO₂ storage will help to meet global climate goals. The research agenda published by National Academies of Sciences Engineering Medicine (2019) calls for roughly $1 billion over a 10–20 years time period to advance the deployment of CO₂ sequestration in deep sedimentary reservoirs at the GtCO₂/yr scale and develop CO₂ mineralization at the MtCO₂/yr scale. This would lead to a deeper understanding of the reservoir characteristics from the nano- to kilometer scale, some of which may include the distribution of the reaction products, the reaction rate of the minerals, the permeability evolution, the pressure build-up in the reservoir, the large-scale impact of chemicophysical processes leading to clogging or cracking, the effects of potential geochemical contamination, etc. This overview presents the advantages, drawbacks, costs, and CO₂ storage potential of each technique, the current and future projects in this domain, and potential sequestration options in geologic formations around the world.