Abstract: The solid waste (coal-based solid waste), liquid waste (mine water), and gaseous waste (power plant flue gas) generated during coal mining and utilization pose significant ecological challenges. The low-carbon disposal and utilization of these three types of waste (hereafter referred to as the “three wastes”) are essential for achieving sustainable development goals. Focused on the strategic objectives of near-zero ecological damage and water-conservative mining, a water-conservative coal mining technology system is proposed. It proposes a water-conservative coal mining technology system based on aquifer structure-controlled, utilizing the coordinated mineralization of solid, liquid, and gaseous wastes in coal mining areas. The system employs multi-source coal-based solid waste, high-salinity mine water, and power plant flue gas to synergistically prepare CO₂-mineralized filling materials. These materials are engineered to form high-porosity injection fillers that effectively support mining-disturbed rock masses while enabling stable CO₂ sequestration, meeting the critical requirements for strength, fluidity, and stability. The technology has been successfully applied in various water-conservative coal mining scenarios, including grouting of water-resisting layers, simultaneous extraction and injection operations, and delayed backfilling of goaf areas. A scientific framework is defined for coordinated mineralization-based injection and backfilling in water-conservative mining, establishing a theoretical system for the mineralization mechanisms and strength of filling materials derived from coal-based solid waste, high-salinity mine water, and CO₂. It elucidates the development mechanisms of mineralized filling materials from solid, liquid, and gaseous waste sources, reveals the carbon sequestration and stability mechanisms of synergistically mineralized materials, and clarifies the hydrophobic and anti-permeability mechanisms of mineralized backfill materials. Building on this foundation, key technologies were developed, including the preparation of three-waste synergistic mineralized filling materials under ambient conditions, CO₂ foaming mineralization technology for three-waste injection and backfill materials, and hydrophobic modification techniques to enhance the impermeability of three-waste synergistic mineralized filling materials. This integrated technical system provides a clear pathway for water-conservative coal mining through the synergistic utilization of solid, liquid, and gaseous wastes, based on the combination of multi-source coal-based solid waste, high-salinity mine water, and power plant flue gas. It offers a comprehensive solution for transforming coal resource development from the traditional emission-intensive model toward a model of near-zero ecological damage and negative carbon emissions. The realization of the “dual carbon” goals is supported, and the green, low-carbon transformation of the coal industry is promoted.