Abstract: Carbon Dioxide Geological Utilization and Storage (CGUS) constitutes a pivotal technological pathway, instrumental to the advancement of global carbon mitigation efforts and the realization of China's Dual Carbon Objectives. The conventional pathway of CCUS is plagued by limitations such as low storage capacity and high costs. Sole reliance on depleted oil and gas fields or deep saline aquifers to achieve climate goals is projected to necessitate nearly US1.3 trillion in capital expenditures. This daunting requirement not only underscores the challenges in sourcing low-cost, scalable storage sites, but also presents strategic opportunities for technological innovation and cross-sector collaboration. In recent years, basalt carbonation technology has gradually emerged as a research hotspot within CGUS. Furthermore, long-term, large-scale, and intensive mining activities have formed vast underground cavity groups within igneous formations, which show potential as strategic sites for CO2 storage. However, research on CO2 storage methods utilizing goafs in igneous rock strata remains notably scarce, significantly impeding the development of CGUS technologies and the advancement of low-carbon to carbon-negative green mining practices in metal mines. Through a systematic review and analytical assessment of the interaction mechanisms between different types of igneous rocks and CO2, the methods and functions of CO2 storage in ultramafic-mafic rocks and intermediate-felsic rocks have been clarified. Building on this foundation and based on the functional backfill technology in metal mining, guided by the integrated concept of “enhancing resource recovery, preventing goaf hazards and utilizing goaf spaces, treating solid waste, and ensuring safe storage of CO2”, an innovative perspective has been proposed: the realization of a “Three-Step Synergistic Method for Pillar Recovery and Backfill-Carbon Sequestration” in igneous rock goafs by constructing sealed backfill chambers. The key technical steps are as follows: (a) preparation of two types of pre-carbonated backfill materials using either direct aqueous mineralization or indirect mineralization, where the material for artificial pillars undergoes moderate carbonation, while the solid waste backfill material is completely carbonated; (b) construction of an artificial support array to actively and controllably replace and recover the original mine pillars, thereby increasing the resource recovery rate; (c) Simultaneous construction of a sealed backfill chamber to provide an engineered trap for subsequent free-phase CO? storage; (d) backfilling of the fully carbonated solid waste material into the chamber, which, after hardening, integrates with the artificial pillars to form a composite backfill structure; (e) sealing the backfill chamber and injecting CO2 to achieve synergistic CO2 storage via mineralization, free-phase trapping, and adsorption.