1 Sedimentary-type and Sandstone-type Uranium Resources Over the past three decades,with the success in in-situ leach(ISL)mining of sandstone-type uranium deposits(SUD),the quantity,resources and production of
The uranium deposits in the Tuanyushan area of northern Qaidam Basin commonly occur in coal-bearing series. To decipher the U-enrichment mechanism and controlling factors in this area, a database of 72 drill cores, in...The uranium deposits in the Tuanyushan area of northern Qaidam Basin commonly occur in coal-bearing series. To decipher the U-enrichment mechanism and controlling factors in this area, a database of 72 drill cores, including 56 well-logs and 3 sampling wells, was examined for sedimentology and geochemistry in relation to uranium concentrations. The results show that coal-bearing series can influence uranium mineralization from two aspects, i.e., spatial distribution and dynamic control. Five types of uranium-bearing rocks are recognized, mainly occurring in the braided river and braided delta sedimentary facies, among which sandstones near the coals are the most important. The lithological associations of sandstone-type uranium deposits can be classified into three subtypes, termed as U-coal type, coal-U-coal type, and coal-U type, respectively. The coal and fine siliciclastic rocks in the coal- bearing series confined the U-rich fluid flow and uranium accumulation in the sandstone near them. Thus, the coal-bearing series can provide good accommodations for uranium mineralization. Coals and organic matters in the coal-bearing series may have served as reducing agents and absorbing barriers. Methane is deemed to be the main acidolysis hydrocarbon in the U-bearing beds, which shows a positive correlation with U-content in the sandstones in the coal-bearing series. Additionally, the 613C in the carbonate cements of the U-bearing sandstones indicates that the organic matters, associated with the coal around the sandstones, were involved in the carbonation, one important component of alteration in the Tuanyushan area. Recognition of the dual control of coal-bearing series on the uranium mineralization is significant for the development of coal circular economy, environmental protection during coal utilization and the security of national rare metal resources.展开更多
Uranium is an environmentally hazardous element,and is commonly present at trace levels(2.4 μg/g for world coals)in coal deposits.However,selected coal deposits could be highly enriched in uranium.In this study,15 co...Uranium is an environmentally hazardous element,and is commonly present at trace levels(2.4 μg/g for world coals)in coal deposits.However,selected coal deposits could be highly enriched in uranium.In this study,15 coal samples were collected from Eastern Yunnan coal deposits,China,aiming to characterize the distribution and the occurrence of uranium in those coals.In studied samples,uranium content varied from 0.36 to 8.28 μg/g,with an average value of 3.76 lg/g.Generally,uranium content in coals from northern coal mines(3.02±2.44 μg/g,n=5)were lower than it in southern coal mines(4.13±2.30 μg/g,n=10).Uranium in coal samples showed no obvious correlation with total sulfur,whereas was positively correlated with ash yield.The results of sequential chemical extraction procedure confirm that organic-bound is the dominant occurrence of uranium.The slight enrichment of uranium in studied coals was probably attributed to sedimentation processes,hydrological conditions and tectonic structure of the coal deposits.展开更多
Between the alternative sources available for the electricity production, still lacks reliability for the production in base units. For the electricity production from 500 MW to 1,000 MW or more, the coal-fired therma...Between the alternative sources available for the electricity production, still lacks reliability for the production in base units. For the electricity production from 500 MW to 1,000 MW or more, the coal-fired thermal and nuclear power plants with uranium have proved competitive and with a high level of reliability and maturation, besides presenting the fuel supply security. This paper presents an analysis of technical feasibility for the choice of the best technology for generating electricity on a large scale, based on coal-fired thermal or nuclear power plant using uranium. This paper takes in account the availability of fuel sources, investments costs, thermal power generation systems, pollutants emission and mitigation technologies, global efficiency, fuel consumption, costs of electricity, construction time and an average lifespan of the installation. Thus the analysis allows the most rational choice of technology for the production of electricity with lower electricity costs and lower COz emissions.展开更多
基金financially supported by China Geological Survey Special Project (No. 12120114009201)Independent Innovation Program for Graduate Students of Northwestern University (YZZ14019)
文摘1 Sedimentary-type and Sandstone-type Uranium Resources Over the past three decades,with the success in in-situ leach(ISL)mining of sandstone-type uranium deposits(SUD),the quantity,resources and production of
基金supported by the Major National Science and Technology Program of China (grants No. 2016ZX05041004)the National Natural Science Foundation of China (grant No. 41572090)High-level Talent Recruitment Project of North China University of Water Resource and Electric (grant No. 40481)
文摘The uranium deposits in the Tuanyushan area of northern Qaidam Basin commonly occur in coal-bearing series. To decipher the U-enrichment mechanism and controlling factors in this area, a database of 72 drill cores, including 56 well-logs and 3 sampling wells, was examined for sedimentology and geochemistry in relation to uranium concentrations. The results show that coal-bearing series can influence uranium mineralization from two aspects, i.e., spatial distribution and dynamic control. Five types of uranium-bearing rocks are recognized, mainly occurring in the braided river and braided delta sedimentary facies, among which sandstones near the coals are the most important. The lithological associations of sandstone-type uranium deposits can be classified into three subtypes, termed as U-coal type, coal-U-coal type, and coal-U type, respectively. The coal and fine siliciclastic rocks in the coal- bearing series confined the U-rich fluid flow and uranium accumulation in the sandstone near them. Thus, the coal-bearing series can provide good accommodations for uranium mineralization. Coals and organic matters in the coal-bearing series may have served as reducing agents and absorbing barriers. Methane is deemed to be the main acidolysis hydrocarbon in the U-bearing beds, which shows a positive correlation with U-content in the sandstones in the coal-bearing series. Additionally, the 613C in the carbonate cements of the U-bearing sandstones indicates that the organic matters, associated with the coal around the sandstones, were involved in the carbonation, one important component of alteration in the Tuanyushan area. Recognition of the dual control of coal-bearing series on the uranium mineralization is significant for the development of coal circular economy, environmental protection during coal utilization and the security of national rare metal resources.
基金This work was supported by the National Basic Research Program of China(2014CB238903)the National Natural Science Foundation of China(41173032,41371444,41373110)+1 种基金the open project of Anhui Key Laboratory(ZYZWSW2014011)Anhui Provincial Department of Education University Scientific Research Project(KJ2020A1204).We acknowledge editors and reviewers for polishing the language of the paper and for in-depth discussion.
文摘Uranium is an environmentally hazardous element,and is commonly present at trace levels(2.4 μg/g for world coals)in coal deposits.However,selected coal deposits could be highly enriched in uranium.In this study,15 coal samples were collected from Eastern Yunnan coal deposits,China,aiming to characterize the distribution and the occurrence of uranium in those coals.In studied samples,uranium content varied from 0.36 to 8.28 μg/g,with an average value of 3.76 lg/g.Generally,uranium content in coals from northern coal mines(3.02±2.44 μg/g,n=5)were lower than it in southern coal mines(4.13±2.30 μg/g,n=10).Uranium in coal samples showed no obvious correlation with total sulfur,whereas was positively correlated with ash yield.The results of sequential chemical extraction procedure confirm that organic-bound is the dominant occurrence of uranium.The slight enrichment of uranium in studied coals was probably attributed to sedimentation processes,hydrological conditions and tectonic structure of the coal deposits.
文摘Between the alternative sources available for the electricity production, still lacks reliability for the production in base units. For the electricity production from 500 MW to 1,000 MW or more, the coal-fired thermal and nuclear power plants with uranium have proved competitive and with a high level of reliability and maturation, besides presenting the fuel supply security. This paper presents an analysis of technical feasibility for the choice of the best technology for generating electricity on a large scale, based on coal-fired thermal or nuclear power plant using uranium. This paper takes in account the availability of fuel sources, investments costs, thermal power generation systems, pollutants emission and mitigation technologies, global efficiency, fuel consumption, costs of electricity, construction time and an average lifespan of the installation. Thus the analysis allows the most rational choice of technology for the production of electricity with lower electricity costs and lower COz emissions.
