常見例句雙語例句So pillar extraction is a problem to be solved presently.因此煤柱的回收是目前急需解決的問題。In order to solve the technical problems of mining strip extraction coal-pillar and waste disposal, the waste substitution extraction is proposed.針對建下條采煤柱回收和井下矸石處理的重大技術(shù)難題，提出矸石置換開采。A long-term practice has proved that the pillar extraction method is suitable not only for the recovery of orebody no. 8 in this mine but also achieves better economic effects.經(jīng)過多年的生產(chǎn)實踐證明，此種礦柱回采方案對東桐峪金礦8號脈礦柱的回采是適宜的，并且收到了較好的經(jīng)濟效益。 返回 pillar extraction