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.

 
  • 針對無(wú)底柱采礦存在的問(wèn)題,闡述了大間距與低貧化工藝的形成及原理,采用該結構及工藝是降低產(chǎn)品成本的有效方法。
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