Recent developments in CO2 permanent storage using mine waste carbonation

Abstract

Accelerated climate change driven by human activities necessitates urgent measures to mitigate greenhouse gas emissions, particularly CO₂. Mineral carbonation has gained traction due to its potential to sequester CO₂ permanently in stable carbonate minerals. This review comprehensively examines recent advancements in utilising mine wastes for CO₂ mineral carbonation, focusing on their feasibility, efficiency, and economic viability. Various mine wastes, including ultramafic, sedimentary, and iron-rich wastes, offer substantial CO₂ sequestration potential due to their inherent mineral compositions conducive to carbonation reactions. The utilisation of mine wastes for CO₂ mineral carbonation not only addresses the challenge of managing large volumes of mining by-products but also contributes to reducing atmospheric CO₂ levels. Laboratory and field studies have demonstrated the effectiveness of direct and indirect carbonation processes, highlighting factors such as particle size, temperature, pressure, and mineralogy that influence carbonation efficiency. Despite the promising results, significant obstacles remain, including slow reaction kinetics, high energy and economic costs, and the need for scalable and sustainable solutions. This review identifies key research gaps and proposes strategies to enhance the economic feasibility and scalability of mine waste carbonation. Integrating carbonation processes with existing mining operations and waste management practices can provide synergistic benefits, reducing costs and environmental impacts. Future research should focus on optimising process parameters, developing novel catalysts, and exploring the potential of recovering valuable by-products during carbonation. By addressing these challenges, CO₂ mineral carbonation using mine wastes can become a viable strategy for sustainable mine waste management and climate change mitigation.