Underground Disposal of Coal Gangue Backfill in China MDPI
China's total coal production in 2021 exceeded billion tons, 52% of the world's total. Coal gangue, a solid waste of coal mining accounts for 1520% of coal production, when directly discharged on the ground surface as waste heaps, it occupies large areas of land and cause environmental pollution. This paper summarizes the existing gangue backfilling methods, their working ...