铀矿地表堆浸对环境的影响

文章以国内2座开采历史较长的铀矿山为例,研究了铀矿地表堆浸生产对环境的影响。按照核工业辐射环境评价的基本要求,主要从矿山废物等的表面氡析出率、废水的放射性核素质量浓度、废渣的γ辐射水平及其放射性核素质量浓度等几个方面进行调查,并与2座矿山生产前期（以常规水冶生产为主）对环境所产生的影响进行比较,评价地表堆浸的优劣;结合地表堆浸的特点提出了改进的措施和建议。     

Fluid inclusion studies on the Koraput Alkaline Complex,Eastern Ghats Province,India: Implications for mid-Neoproterozoic granulite facies metamorphism and exhumation

Following ultrahigh temperature granulite metamorphism at ∼1 Ga, the Eastern Ghats Province of India was intruded by the Koraput Alkaline Complex, and was subsequently re-metamorphosed in the granulite facies in the mid-Neoproterozoic time. Fluid inclusion studies were conducted on silica undersaturated alkali gabbro and syenites in the complex, and a pre-metamorphic pegmatitic granite dyke that intrudes it. High density (1.02–1.05 g/cc), pseudo-secondary pure CO₂ inclusions are restricted to metamorphic garnets within the gabbro and quartz within the granite, whereas moderate (∼0.92–0.95 g/cc) and low density (∼0.75 g/cc) secondary inclusions occur in garnet, magmatic clinopyroxene, plagioclase, hornblende and quartz. The isochores calculated for high density pseudo-secondary inclusions pass very close to the peak metamorphic window (∼8 kbar, 750 °C), and are interpreted to represent the fluid present during peak metamorphism that was entrapped by the growing garnet. Microscopic round inclusions of undigested, relict calcite in garnet suggest that the CO₂ present during metamorphism of the complex was internally derived through carbonate breakdown. Pure to low salinity (0.00–10.1 wt% NaCl equivalent) aqueous intra-/intergranular inclusions showing unimodal normal distribution of final ice-melting temperature (T_m) and temperature of homogenization (T_h) are present only in quartz within the granite. These represent re-equilibrated inclusions within the quartz host that were entrapped at the metamorphic peak. Rare, chemically precipitated graphite along the walls of carbonic inclusions is interpreted as a post-entrapment reaction product formed during decompression. The fluid inclusion evidence is consistent with rapid exhumation of a thickened lower crust following the mid-Neoproterozoic granulite facies metamorphic event. The study suggests that mantle CO₂, transported by alkaline magma into the crust, was locked up within carbonates and released during granulite metamorphism.     

云南澜沧银铅锌多金属矿床含矿岩系地球化学

矿床含矿岩系下石炭统依柳组(C1y)火山岩系形成于陆内裂谷构造环境,具有大陆碱性玄武岩特征。岩系中成矿元素铅、锌(特别是铅)背景值较高,为区内银铅锌多金属矿重要矿源层;岩系因子分析表征:Cu、Pb、Zn、As、Sb、Sn、Ag、Au等元素与Cu、Bi、Sn、Mo、Se、W等元素均代表不同期次成矿作用和主要成矿元素组合,对指导区带成矿环境与成矿作用具有一定理论意义。     

北安地区可地浸砂岩型铀矿成矿地质条件分析

松辽盆地北部北安地区跨盆地内北部倾没区和东北隆起区两个Ⅲ级构造单元。本文对松辽盆地北安地区可地浸砂岩型铀矿成矿条件分析后认为,该区具有丰富的铀源和良好的可地浸砂岩型铀矿成矿条件。具体表现在区内富含有机质,有利沉积相带发育,泥岩—砂岩—泥岩结构层发育良好,有含水透水层和隔水层,补—径—排机制较完善,水动力条件较好,具有渗入型自流水盆地特征,具备了可地浸砂岩型铀矿成矿地质条件,具有良好的勘探前景。     

堆浸铀矿堆液体饱和渗流规律的研究

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。     

溶蚀岩体的溶渗作用及岩溶坝区的渗透性研究

溶蚀岩体的溶蚀作用漫长而不均,处于岩溶坝区其溶渗作用会显著加剧,机理更为复杂。坝区的渗透特性受高应力场的作用,其固有的非均质各向异性更趋复杂,采用确定性的方法不能准确的描述其本质特性。在分析溶蚀岩体溶渗作用的基础上,对K.G.Magomedov预测模型进行了讨论,提出了岩溶管道渗透特性的处理方法。对岩溶坝区透水性随机场进行分析,考察岩溶坝区主要的两场作用,即渗流与应力场的耦合,基于Taylor随机有限元建立了渗流应力耦合的随机微分方程格式,并对耦合随机模型反演求解渗透参数提出了思路。     

322矿田铀矿床原地破碎浸出地质技术评估

本文从原地破碎浸出法采矿要求出发，对322铀矿田碎裂蚀变花岗岩型铀矿床（点）的地质构造、岩／矿石物质成分、矿石结构、铀的赋存形式、岩／矿石物理力学参数、矿体形态、产状、规模及矿床水文地质条件进行了研究；通过原地爆破筑堆试验及一系列铀矿的柱浸工艺试验，获得了大量原地破碎浸出参数；运用原地破碎浸出法适用性评价模型对其进行了评价，认为该矿田碎裂蚀变花岗岩型铀矿床适宜采用原地破碎浸出法开采。     

砂岩型铀矿铀源岩中活性铀浸出方法研究

通过对砂岩型铀矿铀源岩样品中活性铀的浸出试验，选择了相对合理的浸取剂，讨论了样品粒度、固液比、称样量、温度、时间等因素对铀浸出率的影响，拟定了一个适用性广，操作条件较宽松、质量稳定的浸取体系和分析方案。该分析方案对不同类型铀源岩中活性铀的浸出率测量相对标准差小10％（n=11）。     

山东淄博煤矿区环境中多环芳烃的初步研究

对山东淄博煤矿区的煤、煤矸石、矿坑排水、煤矸石淋滤水以及煤矿地下水中多环芳烃的含量进行了测试研究。结果表明,该煤矿区的煤及煤矸石中含有多环芳烃;矿坑排水、煤矸石淋滤水及地下水中的多环芳烃与煤层及煤矸石的淋滤有关,煤矿开采引起的多环芳烃污染应引起重视。      

加蓬某地锰矿的降磷工艺研究

通过加蓬某地锰矿物质成分研究查明其中磷的赋存状态,结果未见磷的独立矿物,却发现磷与铁的关系非常密切.采用溶出铁并保留锰相的方法无法彻底除磷,研究发现其主要原因是锰相为基质,铁受其包裹,在不破坏基质锰相的情况下,不可能将铁除去.采用了物理选矿和化学选矿2种方法进行降磷试验,结果表明,采用焙烧-酸浸的工艺可有效降低该锰矿中...