Using mining waste for CO2 sequestration: exploring opportunities through mineral carbonation, nature-based solutions, and CCUS.

Using mining waste for CO₂ sequestration presents a promising solution for managing waste and reducing greenhouse gas emissions. This article provides a comprehensive overview of established CO₂ sequestration methods that can be applied to mining waste eligible for such application. Three techniques were considered: 1) passive mineral carbonation; 2) a nature-based solution (NBS); and 3) carbon capture, utilisation, and storage (CCUS). Passive mineral carbonation involves exposing mining waste rich in Ca and Mg silicates to atmospheric CO₂. NBS explores the reclamation of disposal areas, estimating the carbon sequestration by topsoil, organic amendments, and revegetation. CCUS presents some storage possibilities with CO₂ injection into waste piles and utilisation by incorporating waste and CO₂ into cement products. Furthermore, an innovative proposal for injecting CO₂ into surface and underground coal mining waste disposal areas was described as a potential action. The strategies presented in this article can be considered to offset CO₂ emissions from mining projects while also contributing to waste management and more sustainable production. [ABSTRACT FROM AUTHOR]