铀矿堆浸分形动力学模型

本文采用堆浸铀矿石粒径分布分维数代替其平均粒径,对Mellado等提出的矿石堆浸动力学模型进行了改进。同时采用铀矿柱浸试验确定了铀矿堆浸分形动力学模型参数与堆浸铀矿石粒径分布分维数的关系,建立了铀矿堆浸分形动力学模型,并进一步采用柱浸试验对模型进行了验证。结果表明,所建立的铀矿堆浸分形动力学模型能很好地反映铀矿堆浸铀金属浸出的规律。     

低品位金矿石的堆浸技术

本文主要介绍国外某些低品位金矿石的堆浸技术,即原矿浸出和破碎后矿石的浸出方法。文中着重描述矿石破碎后堆浸方法的全过程以及操作过程中应注意的事项。     

丹尼森公司发现伊里奥特湖铀矿石可用堆浸法处理

【美国《核燃料》1987年2月23日刊第5页报道】丹尼森矿业公司发现,它的伊里奥特湖矿床的铀矿石,用细菌堆浸法处理在商业上是可行的。所谓细菌堆浸,主要是指利用矿水中的细菌将一些铁盐分解,以得到的硫酸来浸出矿石中的铀。去年,这个矿生产了520万磅U_3O_8,其中堆浸法的产量占     

铀矿石细菌堆浸新工艺及其在赣州铀矿的工业化应用

在对铀矿石细菌浸出机理进行探讨的同时,主要介绍了驯化筛选新菌株,新型细菌培养及贫铀浸出剂氧化再生设备———生物接触氧化槽的研制及铀矿石细菌堆浸新工艺工业试验结果,以及工业化生产情况。与常规堆浸工艺相比较,细菌堆浸新工艺具有浸出周期短,酸用量低,节省氧化剂,降低浸出剂用量,浸出液平均铀浓度高等优点。采用新型填料的新型生物接触槽的成功研制,为铀矿石细菌堆浸工业化应用奠定了基础。铀矿石细菌堆浸新工艺的成功研发,填补了我国湿法冶金领域的一项空白。为我国堆浸铀矿山进行技术改造,以及我国大量低品位铀矿石的处理提供了一条经济的技术可行的工艺路线。     

从矿石和其他原料中堆浸提取贵金属的硫酸-氯化物方法

使用氰化物堆浸金对环境污染较大且在寒冷地区效果不佳。使用硫酸-氯化物作浸出剂,在二氧化锰水合物的参与下,改堆浸为沟槽喷淋,不仅减少了对生态环境的危害,使浸出作用的强度增大、速度加快,并且贵金属的回收率高,同时还可以直接从难选冶的,包括高硫高砷的矿石中提取金。     

堆浸铀矿堆氡析出规律的实验研究

堆浸铀矿堆是铀矿山大气氡的主要来源之一。为了揭示堆浸过程中矿堆表面的氡析出规律,以我国南方某铀矿山新上堆的矿石为实验对象,利用自主设计并制造的改进型一维堆浸实验装置,采用局部静态法测定了不同喷淋状态下和排水过程中矿堆表面的氡析出率。结果表明:在布液和改变喷淋强度的瞬间,矿堆表面的氡析出率突然增大,之后随着喷淋的进行而逐渐减小并趋于稳定,且喷淋强度越大,稳定期间的氡析出率反而越小;在排水过程中,氡析出率先迅速减小,而后逐渐增大趋于稳定。     

一些国家和地区的铀矿石加工厂

【英国《核工程师》1993年第34卷第1期第8页报道】一些国家和地区的1992年运行中的铀矿石加工厂如下。阿根廷现有一座运行中的铀矿石加工厂,即圣拉斐尔工厂。采矿方法是露天开采。其运营者为阿根廷国家原子能委员会。它的生产能力为120吨铀/年。1992年的产量为18吨铀。矿石加工工艺为堆浸加离子交换。澳大利亚现有运行中的铀矿石加工厂     

日本人形(山上下)事业所的铀精制和转换

【《日本矿业会志》1981年第8期第860页报道】一、堆浸、精制和转换中间厂的概要 1.综合处理系统和主要装置目前,日本的方针是保存人形(?)大部分铀矿,只开采少量矿石供堆浸和试验用(每年约5,000—10,000吨,品位万分之八)。转换工厂所需的大部分铀(每年约100—200吨)由国外进口的黄饼提供,溶解后在流程的中间并入。     

铀矿堆浸生产对环境影响的初步调查

本文概括了堆浸生产对环境影响的特点和主要问题，选择了３个典型堆浸生产工程，主要从堆表面氡析出率、堆浸废水的放射性核素浓度及非放有害元素浓度３个方面初步调查了堆浸生产的环境影响问题，并与常规矿冶所致环境影响进行了比较。最后结合堆浸生产特点提出了一些环保改进措施及建议。     

B&B公司拟开采南加利福尼亚新的金矿山

加拿大B&B采矿公司拟在美国加利福尼亚州南部的Castler山以堆浸法开采一新的露天金矿区,该矿区位于圣贝纳迪诺县Castler山的东Mojave National Scenic地区。该矿区包括5个金矿床,有4个露天金矿可供开采,因为矿区南端的Lesley Ann和Jumbo South矿床可合并为一个矿。据公司代理人、加州矿业和开发顾问Marion Ely II透露,计划在5个金矿开采2600万t矿石。矿石几乎都埋藏在Castler山的3个矿床内:Jumbo     

Scientific Principles, Technology, and Equipment for Hydrometallurgical Processing of Uranium and Complex Ores

The development, over the last 50 years, of a technology for leaching various types of monouranium and complex ores, processed at hydrometallurgical plants, is examined. Leaching processes and the equipment required for them (including autoclave processes) for silicate, aluminosilicate, iron-bearing, carbonate uranium ores and complex uranium-phosphorus-bearing, uranium-vanadium, and uranium-molybdenum ores are described.     

Industrial methods of processing poor uranium ores

In recent years great progress has been achieved in the technology of processing uranium ores. A method of extracting uranium from solutions by means of absorption on resins, developed comparatively recently, now makes it possible to obtain more than 70% of the total extractable uranium. The extraction of uranium with liquid extractants also finds wide application, especially in plants using acid leaching of uranium.The normal methods of mechanical enrichment (gravitation, flotation, etc.) play a comparatively small part. However, with complex and poor ores being used, mechanical enrichment in the processing of uranium ores assumes greater importance. Radiometric enrichment is particularly progressive and this makes use of the radioactivity of uranium minerals for separating them from barren rock.     

Oxidation of pyrite by oxygen and concurrent leaching of uranium from ore under the conditions of an autogenous autoclave process

The technology of autogenous autoclave leaching of uranium from refractory titanate ores (brannerites) which is under development at the All-Russia Research Institute of Chemical Technology is based on the use of low-grade pyrites as the raw material, having no commercial value, to obtain sulfuric acid (dissolving agent) and trivalent-iron sulfate (oxidizer) by using the oxygen in air to oxidize the pyrite present in the ores directly in the process of autoclave leaching of the ore. Studies of the effect of the sulfuric acid concentration and consumption of the pyrite concentrate on the degree of uranium extraction from refractory titanate (brannerite) aluminosilicate ores in the process of autogenous autoclave leaching of uranium have confirmed that low-grade pyrite (pyrite concentrate) oxidized in an autoclave at 160°C can completely replace sulfuric acid and pyrolusite. They have also confirmed a high degree of uranium extraction from the ore into solution (>90%) to residual content in leach cakes at the level 0.005–0.007% with 20–30% consumption of the pyrite concentrate (∼51% pyrite). Ways to decrease the pyrite consumption are indicated. __________ Translated from Atomnaya énergiya, Vol. 102, No. 2, pp. 120–124, February, 2007.     

Sorption-Extraction Processes in Uranium Hydrometallurgy: Processing of Monometallic Uranium Ores

The method used to develop sorption-extraction processes in uranium hydrometallurgy over the last 50 years is examined. The first-generation sorption-extraction processes, ionites, and apparatus are described. Data for the second-generation sorption-extraction technology and improvement of apparatus are generalized.The third generation of these processes is characterized by the adoption of porous anionites AM-p and AMP-p in order to make the kinetic characteristics of the sorption and extraction processes closer to one another, by sorption leaching of uranium ores, and by adoption of double synergetic mixtures of extracting agents at the stage of repurification of the commercial reclaim and by the development of fast sorption processes for extracting uranium from productive solutions used in mound and underground leaching. The fourth-generation processes are characterized by the use of high-volume vinyl pyridine ionites, tertiary synergetic mixtures at the extraction stage, combined extraction-desorption processes, solid-phase regeneration of saturated ionites, and conversion of absorbed anions of uranyl-trisulfate into nitrate and chloride complexes. 1 figure.     

The present level of the technology of uranium ore processing

The raw material basis of the uranium industry is presently formed by poor, often complex ores, which are processed on a very large scale. The net cost of uranium production based on this material has been reduced by employing processes which are more effective and economic and by extensive automation. The article gives a review of the present level and development trends of uranium ore processing (mechanical concentration, preparation, leaching, separation processes, sorption, extraction) and the conditions for the use of these processes for ores of different composition. The basic industrial systems of processing the principal types of ores are described. A detailed analysis is given of the basic technical-economic indices of uranium ore processing factories.     

七四五矿蕉坪1号矿体原地破碎浸出开采深孔筑堆技术研究与实践

745 矿赋存着大量低品位铀矿体及零星分散的残余矿体，用常规采矿法难以经济合理地回收这些矿体。为此在蕉坪 1 号矿体的露天矿场底部采用深孔爆破落矿法筑堆进行了万吨级原地破碎浸出试验。根据试验矿体的浸出开采技术条件,选择了适宜的采场底部集液系统,实现了多点集液,防止了浸出液渗漏;为保证堆形规整和提供合适的补偿空间,对切割槽的布置及施工方法进行了探讨;重点研究了深孔落矿方式和参数对爆破块度和爆堆松散程度的影响。     

The reaction between solid UO2 and MnO2 in a sulfuric acid solution

In connection with the extensive use of pyrolusite in the sulfuric acid leaching of uranium from ores, a study was made of the reaction between UO₂ and MnO₂ in a sulfuric acid solution,and possible mechanisms were discussed. The experimental data show that the reaction apparently occurs at the points of contact of the hydrated surface layers of UO₂ and MnO₂; the rate of the process is limited by steric hindrances. On this basis the role of iron ions was also considered in the reaction between a solid oxidizing agent (pyrolusite) and primary minerals of uranium in the acid leaching of uranium-containing ores.In conclution we would like to thank V. G. Romanova for taking part in the work and L. V. Zverev for his useful comments.     

留矿法采场爆破铀矿堆氡渗流析出规律的理论研究

利用氡渗流-扩散运移理论,建立了爆破铀矿堆内氡运移的一维微分方程,推导出爆破铀矿堆渗流出口表面氡析出率的计算公式,阐述了相关物理参数的确定方法。针对一个具体的留矿法采场,研究了通风量、矿堆高度和矿堆渗透率对氡析出率的影响。结果表明：矿堆的氡析出率随风量的增加而增加,并逐渐接近最大氡析出率,但增长速率随风量的增加逐渐降低;在风量较低且通风量相同的条件下,高度越大的矿堆氡析出率越小,随风量的增加,高度大的矿堆氡析出率逐次超过高度小的矿堆,且差距逐渐增大,高度越大的矿堆达到极限氡析出率的风量越大;矿堆的渗透率越小,氡析出率越低,氡析出率相对风量的增长速率越小,接近极限氡析出率的风量越大。