High sulphur deposits with spontaneous firing tendency and under river deposits are restricted to develop due to its technical conditions,especially for the small deposits.

　
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  • 有自燃趨勢的高硫礦床與賦存于河谷下的礦床,由于開(kāi)采技術(shù)條件復雜,限制了該類(lèi)資源的及時(shí)開(kāi)發(fā)利用,尤其是一些小型礦產(chǎn)資源。
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