coal face with sublevel caving 基本例句 综放工作面 At the same time, methane effusing from the coal seam being worked increases, and the emphases of methane control could be put on the methane effusing from coal seam being worked.而大采长综放工作面本煤层瓦斯涌出量增大，则需要增加通风量或者采用新的通风方式。