Carbon capture and storage (CCS) is essential for mitigation of anthropogenic CO2 emissions. Injection of CO2 into depleted gas reservoirs, and even more so for saline aquifers, initiates a series of interconnected physical and geochemical phenomena. The geochemical process within silicate and carbonate reservoirs offers the potential to enhance storge by creating secure CO2 reactions with rock/brine/additives.
Paper SPE 225534 investigated the efficacy of the additives strontium chloride (SrCl2) and barium hydroxide (Ba(OH)2) in accelerating the CO2-trapping mechanisms dissolution and mineralization, their effect on the dissolution of carbonate-bearing minerals, and the changes in the poroelastic properties of the host rock. The additives promoted the formation of less-dense stable carbonate minerals, potentially ensuring that formation integrity is maintained and providing a solution for long-term CO2 storage in saline carbonate aquifers.
Paper CCUS 4423733 investigates the potential for subsurface CO2 storage within igneous rock basalt, which is exceptionally reactive to CO2 and, as a result, has been evaluated because of rapid mineral/fluid reactions that promote long-term storage security. Dissolution of basaltic minerals and precipitation of secondary phases alter fluid geochemistry and, potentially, pore structure during CO2 injection and storage. In this paper, experiments quantified dissolution of basaltic primary minerals and conditions favorable for secondary phase formation under deep subsurface conditions.
Paper 231806 explores the potential for subsurface microbial activity leading to biomineralization as a novel process for long-term CO2 storage. A key microbial process involved in biomineralization is ureolysis, in which urease enzymes hydrolyze urea into ammonium and carbonate ions, resulting in an increase in pH, which promotes precipitation of carbonate minerals. The effects of subsurface conditions, including the composition of injected CO2, on microbial community composition, proliferation, and biomineralization are discussed.
Several other recent publications provide insight into the advancement in our understanding of CCS processes. The effect of low-concentration impurities (SO2, NO2, H2S) within CO2 injected into saline carbonate aquifers is presented in paper SPE 229122.
Paper SPE 227600 explores the effect of brine/CO2 interaction with clay-rich formations to better understand the interaction that leads changes in cation-exchange capacity and higher swelling potential, particularly in montmorillonite relative to illite clay.
The potential application of chelating agents [ethylenediamine tetra acetic acid (EDTA) and N, N dicarboxymethyl glutamic acid (GLDA)] are evaluated in paper SPE 229153 to allow effective CO2 injection in highly saline carbonate aquifers by preventing premature carbonate precipitation and pore blocking during CO2 injection within the near-wellbore region.
Summarized Papers in This September 2026 Issue
SPE 225534 Alkaline Earth Metals Enhance CO2 Mineralization in Saline Aquifers by Tatenda R. Marapira, SPE, Saad F. Alafnan, SPE, and Arshad Raza, King Fahd University of Petroleum and Minerals, et al.
CCUS 4423733 Secondary Mineral Formation Examined During CO2/Basalt Interaction by Elizabeth Appiah, SPE, Ernest Owusu, SPE, and Jason Simmons, SPE, New Mexico Institute of Mining and Technology, et al.
SPE 231806 Study Explores Potential of Subsurface Biomineralization in CO2 Injection, Storage by Stephen Heath, SPE, Creative Chemical Solutions; Khosro Jarrahian, Petronas and Heriot-Watt University; and Eric MacKay, SPE, Heriot-Watt University
Recommended Additional Reading
SPE 229122 How Do Low-Concentration Reactive Impurities in the CO2 Stream Impact Geochemical Reactions in Chalk Reservoirs? by R. Mokhtari, Technical University of Denmark, et al.
SPE 227600 Capturing Clay/CO2 Interactivity Through Water Analysis for CO2-Storage Applications by Azizah Al Radhwan, SLB, et al.
SPE 229153 Enhancing CO2 Sequestration in Deep and Highly Saline Aquifers Using Chelating Agents by Mohammed Mahtab Ahmed, King Fahd University of Petroleum and Minerals, et al.
Myles Jordan, SPE, is a subject matter expert for inorganic scale management with ChampionX. He has been with the company since 1997. Jordan holds a BS degree in geology/chemistry and PhD degree in geochemistry. His current interests include the development of topside/downhole inorganic scale-management programs within the Americas, North Sea, Middle East, and west Africa, along with the investigation of new scale-inhibitor molecules, novel deployment applications, and monitoring methods for scale control. Jordan has been an author or co-author of over 200 SPE, National Association of Corrosion Engineers, and Royal Society of Chemistry papers on inorganic scale management and associated formation-damage remediation. He has been an honoree professor at the Institute of GeoEnergy Engineering at Heriot-Watt University for the past 12 years.