煤层地下气化腔粉煤灰矿化封存CO2研究OA

To address the dual challenges of global carbon emissions and industrial solid waste disposal,this study proposes an integrated"carbon sequestration-solid waste disposal-abandoned cavity utilization"three-in-one engineering scheme.This scheme combines abandoned cavities from Underground Coal Gasification(UCG)with fly ash mineralization for CO2 sequestration.Using CMG-STARS software,a 3D,three-phase,five-component coupled model was developed to simulate the thermodynamic and mineralization behaviors during the injection of fly ash slurry and CO2.The study focused on the effects of different CO2 injection rates on temperature field evolution and sequestration efficiency.The results indicate that increasing the CO2 injection rate significantly enhances the intensity and spatial uniformity of the mineralization reaction.For the same total injection volume,increasing the rate from 20000 m3/d to 60000 m3/d improves the sequestration efficiency by approximately 15％.While the injection of low-temperature CO2 initially causes a cooling effect,the exothermic nature of the mineralization reaction gradually reverses this trend,stabilizing the temperature at approximately 250℃.This study provides a theoretical basis and parameter optimization strategies for the development of this integrated engineering technology.