Feasibility of Recycling Bayer Process Red Mud for the Safety Backfill Mining of Layered Soft Bauxite under Coal Seams

The mining of layered soft bauxite under coal seams (BCS) will cause serious underground goaf disasters and surface Bayer process red mud (BRM) pollution. In order to realize the safe efficient BCS, feasibility recycling BRM as a backfilling aggregate was explored. A series tests were conducted prevent pollution diversion from storage goafs, numerical simulation analysis carried out based on FLAC3D protect overlying seam. results show that: action encapsulation, solidification inhibiting precipitation cementitious materials, leaching concentration harmful substances in mud-based cemented backfill (RCB) can be reduced 70% more than fresh BRM. Mining disturbance redistributes in-situ stress field strata; normal not only reduce pressure pillars, but also release tensile roof floor +0.4956 MPa ?0.1992 MPa, effectively preventing subsidence. Since creep damage past absorb dissipate lots energy, range caused by is controlled within 3 m, which 10% open-stope method.