This coal mine are rare byerlyte with good quality.As shown by complicated study of coal quality,in order to use resource resonably and gain maximum b...

 
  • 煤质的综合研究表明,为达到珍惜和合理利用资源,并使其效益最大化,该煤层应以冶金和铸造用焦为主要加工利用方向。
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