【摘要】 煤矿采空区空间巨大，且伴随着大量CO₂的排放，导致严重的生态和环境挑战。提出将泡沫混凝土（FC）与CO₂相结合的方案，制备一种新型CO₂原位封存的CO₂发泡充填材料（CFC）。研究了不同CO₂浓度对CFC试样浆液性能、力学性能以及微观结构演化的影响规律。结果表明，CO₂浓度为60%时，干密度、抗压强度最高，3 d抗压强度较对照组增加了26.1%。微观测试结果显示，CO₂引入形成CaCO₃晶体，使CFC孔壁增厚，骨架结构致密，且根据CaCO₃的失重峰面积计算得出60%CO₂浓度的CFC试样固碳量可以达到239 g CO₂/m³。此外，随CO₂浓度升高，对泡沫液膜产生影响，导致CO₂发生逃逸，固碳效果变差。研究为大规模使用CO₂矿化封存充填技术提供见解，也为煤炭绿色利用作出贡献。更多还原

【Abstract】 The coal mines have vast goaf areas and is coupled with substantial CO₂ emissions, which pose significant ecological and environmental challenges. This study was proposed an innovative approach that integrated foam concrete（FC） with CO₂ to develop a novel CO₂ in-situ sequestering foam backfill material（CFC）. This study was systematically investigated the influence of varying CO₂ concentrations on the slurry properties, mechanical performance, and microstructural evolution of CFC specimens. The results demonstrated that at 60% CO₂ concentration, the CFC specimens achieved optimal dry density and compressive strength, with the 3 d strength showing a 26.1% increase compared with the control group. Microstructural analysis revealed that CO₂ incorporation induced CaCO₃ crystallization, leading to pore wall thickening and densified skeletal structure. Furthermore, quantitative thermal analysis based on the mass loss peak area of CaCO₃ indicated that the CFC specimens at 60% CO₂ concentration achieved a CO₂ sequestration capacity of 239 g CO₂/m³. Moreover, elevated CO₂ concentrations was adversely affected foam liquid films, inducing CO₂ escape and consequently diminishing carbon sequestration efficiency. This study provides critical insights for large-scale implementation of CO₂ mineralization filling technology, while contributing to green coal utilization strategies.更多还原