Technology of Fully Mechanized High Efficient Backfill Coal Mining with Annual Production of One Million Tons

In order to realize the safety and high eficient mining of the coal resources under the surface buildings, railway and water body in Fengfeng Mining Are a, the fully mechanized coal mining technology, backfill system, equipment selection, surface ground deformation control and others of the coal mining face with annual coal production of one million tons were conducted.The backfill mining effect showed that the deformation of the surface ground subsidence area above the backfill coal mining face was controlled within 88 mm and the damage of the surface buildings caused by the mining subsidence could be controlled within I grade mining influence「 ange.The annual coal production of the backfill mining face was realized over one milion tons .There were coal rejects with 600 000 t and fly ash with 300 000 t annuall y applied to backill operation of the coal mining face.The service life of the mining area was extended by 20 years.