The style of two coal seams being mining at the same time is adopted.Stoping safely is accomplished,the coal yield is improved and rather than notability economy benefit is achieved.

 
  • 葛店煤矿采取了上下两层煤同时开采的方式,实现了安全回采,提高了煤炭回收率,带来显著的经济效益。
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