【摘 要】
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Under the specific geological condition,uranium and other metal elements are absorbed in coal,or even mineralized to form coal-uranium-polymetallic deposits.The coal-uranium-polymetallic ores are gene
【机 构】
：
Dept. of Engineering Physics of Tsinghua Univ,Beijing 100084,China
论文部分内容阅读
Under the specific geological condition,uranium and other metal elements are absorbed in coal,or even mineralized to form coal-uranium-polymetallic deposits.The coal-uranium-polymetallic ores are generally burnt in blast furnaces for metal concentrated before smelted or extracted.6 This research case was carried out in Yunnan Province,China.The coal enriches uranium and rare metal elements.Rare metals in dust or fly ash removed from bag filter is 2.32% comparing to 0.053% in original coal after combustion in the temperature over 1000 ℃.The fly ash is the product of concentrated metal.Meanwhile,the concentrations of the radionuclides in ashes increase.A fraction of them remain in bottom ash,some enrich in fly ash,and the rest is released to atmosphere from bag filter,as a result,the level of environmental radiation enhanced.
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