Abstract: | Mineable coal reserves in thick and extra-thick seams account for 44% of the total deposit in China. Fully-mechanized top-coal caving technology is a new mining method of safe and efficient underground operations in extra-thick seams in China. The development of fully-mechanized top-coal caving technology in China, which was successfully applied in Face 8105 in Tashan Coal Mine, Datong, Shanxi, China, is analyzed in this paper. Studies on movement pattern of top-coal and roof from fully-mechanized top caving face in 14–20 m extra-thick seams have been carried out. A series of key technologies were successfully developed, including strata control technology, equipment for high-efficient and high-recovery top caving operations, and safety guarantee technology for low gas occurrence and high gas emission. As a result, the fully-mechanized top-coal caving Face 8105, with large mining height in Tashan Coal Mine, has achieved a recovery rate of 88.9% and an average equipment operation rate of 92.1%. With coal production of 10.84 Mt in 2011, the demonstration project is a technology and equipment breakthrough for fully-mechanized top-coal caving face in extra-thick coal seams with large mining height. |