In the light of the problems in the nonpillar mining, the formation and principles of the wide spacing and the low lean ore drawing process are presented.

 
  • 针对无底柱采矿存在的问题,阐述了大间距与低贫化工艺的形成及原理,采用该结构及工艺是降低产品成本的有效方法。
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