Continuous Extraction and Continuous Backfill Mining Method Using Carbon Dioxide Mineralized Filling Body to Preserve Shallow Water in Northwest China

The exploitation and utilization of coal resources are not only prone to causing water table lowering, but also produce a large amount CO2 coal-based solid waste. A scientific concept that employs the wastes develop filling bodies inject them into mined-out area, sequestrate mitigate overburden migration thus preserve overlying aquifer, is proposed. Continuous extraction continuous backfill (CECB) mining was selected as method meet aforementioned objectives. Additionally, carbon dioxide mineralized body (CMFB) under ambient temperature pressure developed, with fly ash aggregate, gas, silicate additives cement accessories. uniaxial compressive strength (UCS) tensile CMFB various curing times contents were tested indoors. physical analogue simulation FLAC3D numerical calculation then successively implemented on premise determining similar material ratio in calibrating parameters simulation. deformation aquifuge level lowering while using CECB proportion obtained. When 75% content 28 d time, maximum values vertical displacement, horizontal inclination, curvature aquiclude 26 mm, 6.5 0.12 mm/m, 0.08 mm/m 0.0015 mm/m2, respectively, decreased 0.47 m. results show most appropriate realize preservation mining, sequestration harmless treatment wastes, contributing green sustainable development areas.