摘要
铀是重要能源矿产和国家战略资源,煤岩型铀矿对我国核能产业可持续发展和“双碳”目标实现具有重要意义。本文采用X射线荧光光谱(XRF)、电感耦合等离子体质谱(ICP-MS)和X射线光电子能谱(XPS)等手段,研究了伊犁盆地洪海沟矿区煤的元素地球化学、富铀因素以及铀活化迁移过程的价态变化特征。结果表明:①洪海沟煤中U超常富集,平均含量为258.91μg/g。石炭纪—二叠纪中—酸性火成岩和海西期花岗岩是煤中铀的物质来源,稳定的单斜构造,头屯河组砂砾岩和粗砂岩的岩性组合,晚侏罗世以来干旱气候及后生富铀溶液的入渗共同控制煤层中U、Re、Se、Mo等元素共同富集。②煤岩型铀矿的形成与氧化环境中U6+以络合物或酸根形式迁移,氧化—还原过渡环境中富铀含氧流体中U6+被还原成U4+沉淀富集有关。洪海沟矿区弱氧化—还原过渡环境高价态的变价元素被还原,以Se-U-Re-Mo模式共同富集于煤层顶部。③洪海沟矿区“上铀下煤”矿产资源分布和铀矿下部多煤层的发育,需要合理划分煤-铀矿产资源之间保护区距离,上部砂岩型铀矿优先进行地浸开采,下部煤岩型铀矿采用井工开拓方式进行“煤炭地下气化+煤灰原位地浸开采”,将煤灰中铀提取至地表利用,实现煤-铀资源协调开采利用。
Coal-type uranium deposits are critical for the sustainable development of Chinas nuclear energy industry and the achievement of its‘double carbon’goals.This study,using X-ray fluorescence spectroscopy(XRF),inductively coupled plasma-mass spectrometry(ICP-MS),and X-ray photoelectron spectroscopy(XPS),investigates the elemental geochemistry,U-enrichment controlling factors,and valence state characteristics of uranium during activation and migration processes in coals from the Honghaigou mine in the Yili basin.Our results indicated that:①The Honghaigou coal displays abnormally high uranium enrichment,with an average of 258.91μg/g.This enrichment can be attributed to several contributing factors:the presence of U-rich Permian-Carboniferous Hercynian granites with a stable monoclinic structure;the association of sandy conglomerate and coarse sandstone of the Toutunhe Formation;arid climatic conditions following the Late Jurassic;and the infiltration of epigenetic U-rich solutions.These factors collectively controlled the co-enrichment of U,Re,Se,Mo,and other elements in this coal.②In the oxidation zone of the coal-rock-type uranium ore,U6+migrates in the form of complexes or acid radicals.As this migration continues to the oxidation-reduction transition zone,U6+is reduced to U4+and precipitates,leading to enrichment in uranium-rich oxygenated fluids.The uranium content of the original,reduced zone decreases and tends towards a solid state.In contrast,in the weak oxidation-reduction transition zone of the Honghaigou mine,uranium content exhibits a sharp increase,and the high-valence variable elements become co-enriched at the top of the coal seam in the Se-U-Re-Mo combination.③The spatial distribution of mineral resources in Honghaigou mine,characterized by‘upper uranium and lower coal’,alongside the development of multiple coal seams in the lower part of the uranium mine,allows for a strategic and balanced mining approach.The upper sandstone-type uranium mine is preferentially mined by in-situ leaching,while the lower coal-rock-type uranium mine adopts the underground mining method to carry out‘underground coal gasification+coal ash in-situ leaching mining’.This dual mining strategy allows for the extraction of uranium from coal ash and its subsequent utilization on the surface,promoting the coordinated mining and utilization of both coal and uranium resources.
作者
李家新
王文峰
白洪阳
陆青锋
何鑫
王文龙
师志龙
LI Jiaxin;WANG Wenfeng;BAI Hongyang;LU Qingfeng;HE Xin;WANG Wenlong;SHI Zhilong(School of Resources and Geosciences,China University of Mining&Technology,Xuzhou,Jiangsu 221116,China;School of Geology and Mining Engineering,Xinjiang University,Urumqi,Xinjiang 830047,China;School of Civil Engineering,Luoyang Institute of Science and Technology,Luoyang,Henan 471023,China;Nuclear Industry 216 Brigade,Urumqi,Xinjiang 830011,China)
出处
《地质学报》
EI
CAS
CSCD
北大核心
2024年第8期2439-2451,共13页
Acta Geologica Sinica
基金
国家重点研发计划项目(编号2021YFC2902003)
新疆维吾尔自治区重大科技专项(编号2022A03014)
国家自然科学基金项目(编号41972176)
新疆第三次综合科学考察(编号2022xjkk1003)联合资助的成果。
关键词
富铀煤
元素
地球化学
价态
协调开采
uranium-rich coal
element
geochemistry
speciation of uranium
coordinated mining
作者简介
李家新,女,1997年生。硕士,从事煤地球化学研究。E-mail:LJiaxin0306@163.com;通讯作者:王文峰,男,1970年生。教授,博士生导师,长期从事煤地质学研究。E-mail:wenfwang@vip.163.com;通讯作者:白洪阳,男,1989年生。讲师,博士,从事煤地球化学研究。E-mail:bhy1989@163.com。
