CO₂ mineral storage capacity in the Medellín Metaharzburgite based on thermodynamic modeling

Abstract

The atmospheric carbon dioxide (CO₂) content recorded for 2024 was 37.8 Gt, exceeding pre-industrial levels by more than 50% and accelerating the global climate crisis. CO₂ storage in mineral phases is one of the alternatives to counteract the impact of anthropogenic CO₂ emissions. This study estimates the potential for CO2 storage in carbonates in the Metaharzburgite of Medellín, Colombia, in the range 50-300 bar and 30-100 °C by estimating the storage capacity through phase equilibrium (thermodynamic modeling). Our results demonstrate that up to ~10.5 vol.% carbonates could theoretically equilibrate, storing between 0.1251 and 0.1655 tCO₂/m³, with a theoretical maximum of 5.3-9.6 GtCO₂. By adopting a more conservative approach (maximum of 10% of the unit's storage volume), a total storage of 533-840 MtCO₂ is suggested. This means that a volume of 0,121% would suffice to compensate the annual emissions of the Aburrá Valley, demonstrating that the Metaharzburgite of Medellín is a reservoir with CO2 storage potential for Colombia.