Enhancing National GHG Inventories: A Computational Model for CO2 Sequestration in Russia's Ultramafic Mine Tailings

This study develops a computational model to quantify CO₂ sequestration in ultramafic mine tailings, a significant yet underreported carbon sink in Russia's national greenhouse gas (GHG) inventories. Focusing on the natural process of mineral carbonation within ultrabasic rock formations—a prevalent byproduct of the diamond mining industry—our model integrates detailed chemical reactions between key components such as Mg₃(OH)₄Si₂O₅, Mg_3​(OH)₄​Si₂​O₅​, CaCO3​, CO₂, and H₂O, which lead to the formation of stable carbonate minerals capable of long-term CO2 storage.

Utilizing differential equations to simulate the dynamics of CO₂ sequestration, our approach provides insights into the temporal evolution of reactants and products, highlighting the potential of mine tailings as effective carbon sinks. The model addresses the critical need for refining estimates of sequestered CO₂, which has been historically overlooked in the compilation of Russia's national GHG inventories. Given the abundance of ultramafic mine tailings across the country, our findings emphasize the significance of incorporating these natural carbonation processes into national carbon accounting frameworks.

Preliminary results from our model demonstrate the substantial capacity of ultramafic tailings to capture atmospheric CO₂, suggesting that optimizing environmental conditions for carbonation could further enhance sequestration rates. This research not only contributes to the advancement of carbon capture and storage (CCS) technologies in the mining sector but also offers a robust methodology for updating and improving national GHG inventories.

By bridging environmental science with practical policy applications, our study supports the strategic development of sustainable mining practices and underscores the importance of comprehensive GHG accounting in mitigating climate change impacts. This work represents a crucial step towards achieving more accurate and inclusive national carbon inventories, aligning with global efforts to reduce anthropogenic emissions and combat climate change.