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可地浸砂岩型铀矿床中铀赋存状态及铀矿物空间嵌布特征会影响地浸时浸出工艺的选择及溶浸液的优化,研究矿石中铀赋存状态及铀矿物工艺参数对于提高矿床的铀浸出效率具有重要意义。本研究采集了二连盆地乔尔古铀矿区矿石样品,通过扫描电镜、电子探针及综合矿物分析仪(TIMA)等方法,分析铀赋存状态及铀矿物粒度、解离度、连生矿物等工艺矿物学参数。结果表明:(1)乔尔古铀矿区矿石中铀的存在形式主要为铀矿物、含铀矿物和吸附态铀。铀矿物主要为沥青铀矿和少量的铀石。(2)铀矿物粒度较小且变化范围较大,铀石粒径最大可达30~35μm,沥青铀矿粒径最大可达60~65μm;多数铀矿物的粒径小于20μm,其中铀矿物粒径在5~10μm的数量是占比最多(铀石和沥青铀矿分别占总颗粒数量的37.88%和27.78%)。(3)铀矿物解离度较低,解离度小于10%的铀石和沥青铀矿的占比分别为99.72%和91.84%。铀的赋存状态表明乔尔古铀矿区适宜地浸,但实际浸出时铀浸出率可能会受到铀矿物粒度及解离度特征的严重制约,使得经济效益受到较大影响。本研究有效查明了乔尔古铀矿区铀赋存状态以及铀矿物工艺参数,有助于研究制定适合该矿区的地浸采铀... 相似文献
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可地浸砂岩型铀矿床铀赋存状态及铀矿物的工艺矿物学特征会直接影响地浸过程中浸出工艺的选择及铀浸出效率,而地浸工艺的合理选择对铀矿床开采效率和经济效益的提高具有重要意义。本研究采集了二连盆地艾勒格庙铀矿区矿石样品,通过扫描电镜及综合矿物分析仪(TIMA)等方法,分析铀的赋存状态以及铀矿物粒度、解离度、连生矿物等工艺矿物学参数。结果表明:(1)艾勒格庙铀矿区矿石中铀的存在形式主要为铀矿物、含铀矿物和吸附态铀。铀矿物主要为铀石及少量沥青铀矿。(2)铀石粒径最大可达350~400μm,沥青铀矿粒径最大为20~30μm;大多数铀石和全部的沥青铀矿的粒径都小于30μm(分别占总颗粒数量的48.42%和100%)。(3)铀矿物的解离度较低,解离度小于10%的铀石和沥青铀矿的占比分别达到了47.26%和97.08%。与铀矿物连生关系最密切的矿物为黄铁矿、正长石等。铀矿物类型主要为铀石,矿石中碳酸盐矿物含量较低且矿体埋深较浅等特征都表明艾勒格庙铀矿区适宜采用酸法浸出。实际地浸中可通过调控不同溶浸过程溶浸液硫酸浓度,降低非铀矿物对硫酸试剂的消耗。本研究有效查明了艾勒格庙铀矿区铀赋存状态,为制定适合该矿区的地... 相似文献
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可地浸砂岩型铀矿中铀矿物的空间嵌布特征直接影响其与溶浸剂的接触反应程度,厘清铀矿物浸出过程中的嵌布变化规律对于综合提高铀的浸出率至关重要。基于此,本研究采集了钱家店砂岩型铀矿床Ⅳ号矿段样品,进行了室内浸出实验并对中性浸出反应前后矿样进行了SEM-EDS镜下观察、以及TESCAN综合矿物分析等表征手段,定量分析了浸出前后铀矿物嵌布、解离度、连生矿物和粒度变化特征。结果表明:(1)钱家店砂岩型铀矿床独立铀矿物主要以沥青铀矿为主,以及少量铀石,完全被包裹的沥青铀矿和铀石解离度分别由61.06%~68.17%增加至83.45%、由46.88%~58.27%增加至65.22%,指示沥青铀矿的解离度参数变化程度明显大于铀石,说明沥青铀矿更易发生氧化溶解。(2)沥青铀矿和铀石多呈现6~12μm、4~10μm粒径范围与长石、石英、黄铁矿、云母、黏土矿物连生,而这些连生的矿物多呈现包裹铀矿物的状态使铀矿物难以与溶浸液接触反应。(3)浸出之后,可见石英长石碎屑颗粒内部还残留有大量铀矿物,并且其边缘发现有小颗粒(5μm)铀石残余,指示CO2+O2浸出条件下完全被包... 相似文献
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浓酸熟化——一种有效的硬岩铀矿浸出方法 总被引:2,自引:1,他引:1
本文通过对某中生代火山岩型铀矿床矿石进行铀浸出试验研究,认为浓酸熟化浸出法是处理硬岩铀矿石、提高其铀浸出率的一种有效方法。本文所研究的铀矿石,在浸出条件相同的情况下,浓酸熟化法的铀浸出率比常规酸浸法高20%左右。 相似文献
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铀矿堆浸,溶浸液在铀矿堆中的渗流对浸出效果有非常重要的影响,研究堆浸铀矿堆的渗透特性,对改善铀矿堆浸效果具有重要的意义。采用取自我国南方某铀矿山的堆浸铀矿石,配制10组不同粒径分维数的试样,利用自制的饱和渗流试验装置,对其液体饱和渗流的规律进行试验研究,获得相应的渗透率和流态指数。利用试验结果,分析粒径分维数对渗透率的影响。采用支持向量机(SVM)模型,以粒径分维数和孔隙率作为输入量,建立渗透率和流态指数预测模型。结果表明,(1)在文中试验条件下,堆浸铀矿堆的液体饱和渗流遵循非Darcy指数定律,流态指数在1.1~1.5之间,且渗透率随着粒径分维数的增加而逐渐减小;(2)渗透率的SVM预测模型和流态指数的SVM 预测模型给出预测值的相对误差分别低于8%和7%,可以满足工程应用的要求。 相似文献
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考虑核电厂地基-基础的动力相互作用,应用显式动力有限差分法分析了地震作用下极软岩、较软岩、坚硬岩上核电厂建筑结构基础的地震响应特征,比较了岩石坚硬程度对基础加速度反应谱的影响。研究表明:随着岩石坚硬程度的提高,核电厂建筑物结构基础的地震响应有增加的趋势;在周期轴上,基础处的加速度反应谱曲线会随着岩石坚硬程度的提高逐渐向短周期(高频段)方向移动。在高频段,建造于较坚硬岩石上基础结构的加速度反应谱值偏大;在中等频段,建造于较软岩石上基础结构的加速度反应谱值偏大;在低频段,岩石坚硬程度对加速度反应谱的影响不显著。 相似文献
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Ivan V. BRAGIN Georgy A. CHELNOKOV Oleg V. CHUDAEV Natalia A. KHARITONOVA Sergey V. VYSOTSKIY 《《地质学报》英文版》2016,90(1):276-284
Studied waters belong to warm(T=30-50℃),alkaline(pH=8.9-9.3),low mineralized(TDS235 mg/1)Na-HCO_3 or Na-SO_4-HCO_3 thermal waters with high content of SiO_2(up to 81 mg/l)and F(up to 3.9 mg/1),occur on modern volcano-tectonic rejuvenated areas of Eastern Sikhote-Alin orogenic belt.Low~3He concentration as well as N_2/O_2 and N_2/Ar ratios exclude influence of deep mantle fluid.New rare earth element data constrain our understandmg of water-rock interaction occurring in the water source region.Meteoric origin of waters is proved by stable isotope values varying from-71‰to-136.1‰and from-10.8‰to-18.8‰forδ~2U andδ~(18)O respectively.REE patterns reflect high pH,resultfing from water-rock interaction and oxidative conditions.Calculations of deep aquifer temperature using Na-K and quartz geothermometers show 116.8-131.1°C and 82.2-125.8℃respectively.Presence of deep faults both with abnormal thermal gradient(~45-50 K/km)define unique geochemical shape of thermal waters of Sikhote-Alin,area,where no present volcanic activity is registered. 相似文献
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M. D. Sharma 《Journal of Earth System Science》2004,113(2):247-257
Three dimensional scattering of near-field is studied for dilatation and rotation in the time domain. The perturbation method
is applied to solve the equation of motion for the first order scattering from a weak inhomogeneity in an otherwise homogeneous
medium. The inhomogeneity is assumed close enough to the point source so that the near-field intermediate wave is dominating
over the far-field sphericalP andS pulses. The integral expressions are derived to relate dilatation and rotation of scattering to the radial fluctuations of
velocities and density in the inhomogeneity. These integrals are solved to calculate the strains of scattering from (a part
of) an inhomogeneous spherical shell of arbitrary curvature. Variable curvature may allow the shape of inhomogeneity volume
element to change uniformly from spherical to rectangular. Rotation of scattering from a spherical shell is independent ofP wave velocity inhomogeneity. Dilatation of scattering does not involveS wave velocity inhomogeneity but its gradient. The back scattering results are obtained as a special case. Strains are computed
numerically, for hypothetical models to study the effects of various parameters viz., velocity inhomogeneity, distance of
source from inhomogeneity and from receiver, and thickness of inhomogeneity. The curvature of the spherical shell is varied
to study the effects of the shape of inhomogeneous volume element on scattering. 相似文献
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地震次生地质灾害风险评估集对态势分析 总被引:2,自引:0,他引:2
5.12四川汶川8级强震引发了大量次生地质灾害,加剧了灾情并严重影响抗震救灾。地震次生地质灾害受多重因素制约,其孕育与致灾过程具有不确定性。利用集对分析原理与方法,对地震次生地质灾害进行同异反态势分析,拟定了风险评估的集对分析同一度、差异度、对立度等指标体系的构建原则与赋值标准,对承灾体系统的不确定性及其作用作了刻画与分析,建立了不同风险分区代表性的集对分析联系度表达式,为地震灾害研究提供了可资借鉴的新思路和技术方法。 相似文献
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下扬子区三叠纪古地理演化 总被引:2,自引:2,他引:0
下扬子区在三叠纪期间接受了早-中三叠世海相碳酸盐沉积、中-晚三叠世海陆交互相和陆相湖沼沉积.沉积相带的空间分布和古地理格局的变迁明显地受到区域构造的控制.区内盆地发育与演化是在华南板块与扬子板块、扬子板块与华北板块相互作用的背景下进行的.早-中三叠世末期的印支运动是下扬子区构造-古地理格局改变的决定性因素,使下扬子海盆闭合,沉积类型由海相沉积变为陆相沉积.下扬子区三叠纪古地理的演化特征也为板块碰撞提供了沉积证据. 相似文献
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Isothermal thermogravimetric experiments have been carried out to determine the reaction kinetics of the dehydration processes
in fuller's earth, a natural Ca-montmorillonite. Dehydration in swelling clays is a complex reaction, and analysis of the
thermogravimetric data using empirical rate equations and time-transformation analysis reveals that the nature of the rate
controlling mechanism is dependent upon both the temperature regime of the sample as well as the extent of reaction. For fuller's
earth, we find that the dehydration kinetics are dominated by a nucleation and growth mechanism at low temperatures and fractions
transformed (stage I), but above 90 °C the last stages of the reaction are diffusion controlled (stage II). The activation
energy for dehydration during stage I is around 35 kJ · mol−1, whereas the removal of water during stage II requires an activation energy of around 50 kJ · mol−1. These two stages of dehydration are associated with primary collapse of the interlayer (stage I) and movement of water that
is hydrated to cations within the interlayer (stage II).
Received: 28 August 1998 / Revised, accepted: 27 January 1999 相似文献