Energy Technology Data Exchange (ETDEWEB)
Silva, Luciana S. [State University of Bahia (UNEB), Campus Caetite, BA (Brazil); Pecequilo, Brigitte R.S.; Sarkis, Jorge; Nisti, Marcelo B., E-mail: brigitte@ipen.br, E-mail: jesarkis@ipen.br, E-mail: mbnisti@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)
2011-07-01
The Lagoa Real Uranium Province, situated in South Central Bahia in the region of Caetite and Lagoa Real, is considered the most important monomineralic province of Brazil. The urban population who lives in the proximities of this uranium province in the cities of Caetite, Lagoa Real and Livramento uses public supply water, while the inhabitants of the rural area due to long terms of dry weather use water from wells, cisterns, small dams, reservoirs and dikes which are supplied with the rains. In this work it was determined the concentration of uranium in the water consumed by the rural and urban population living in the proximities of the Lagoa Real Uranium Province. The study comprehends 32 sampling spots spread throughout the region of interest. Samples were collected in January and July 2010, covering superficial, underground and public supply water from the region. The uranium concentrations were determined by an inductively coupled plasma mass spectrometer (ICP-MS). Preliminary results showed that the uranium concentrations in the water from the Lagoa Real Uranium Province varied from 0.064 {+-} 0.005 {mu}g.L{sup -1} to 90 {+-} 1,5 {+-}g.L{sup -1}. It was observed that only two of them obtained values higher than the World Health Organization's recommended limit (2011) of 30 {mu}g.L{sup -1} for maximum uranium concentration in the water for human consumption. For a conclusive evaluation, the uranium concentrations results will be analyzed together with total alpha and beta concentrations determined elsewhere for the same samples. (author)
International Nuclear Information System (INIS)
Silva, Luciana S.; Pecequilo, Brigitte R.S.; Sarkis, Jorge; Nisti, Marcelo B.
2011-01-01
The Lagoa Real Uranium Province, situated in South Central Bahia in the region of Caetite and Lagoa Real, is considered the most important monomineralic province of Brazil. The urban population who lives in the proximities of this uranium province in the cities of Caetite, Lagoa Real and Livramento uses public supply water, while the inhabitants of the rural area due to long terms of dry weather use water from wells, cisterns, small dams, reservoirs and dikes which are supplied with the rains. In this work it was determined the concentration of uranium in the water consumed by the rural and urban population living in the proximities of the Lagoa Real Uranium Province. The study comprehends 32 sampling spots spread throughout the region of interest. Samples were collected in January and July 2010, covering superficial, underground and public supply water from the region. The uranium concentrations were determined by an inductively coupled plasma mass spectrometer (ICP-MS). Preliminary results showed that the uranium concentrations in the water from the Lagoa Real Uranium Province varied from 0.064 ± 0.005 μg.L -1 to 90 ± 1,5 ±g.L -1 . It was observed that only two of them obtained values higher than the World Health Organization's recommended limit (2011) of 30 μg.L -1 for maximum uranium concentration in the water for human consumption. For a conclusive evaluation, the uranium concentrations results will be analyzed together with total alpha and beta concentrations determined elsewhere for the same samples. (author)
Uranium deposits of Lagoa Real uranium Province, state of Bahia, Brazil
International Nuclear Information System (INIS)
Ribeiro, C.I.; Carvalho Filho, C.A. de; Hashizume, B.K.
1984-01-01
The Uranium Province of Lagoa Real is situated in the south-central part of the state of Bahia and constitutes, at the present moment, one of the most promising uranium districts of Brazil. The first anomaly was recorded in 1977 and, since then intense exploration and evaluation has been carried out in the area, resulting in the characterization of six ore deposits until now. Simultaneously, NUCLEBRAS has performed tests to establish the beneficiation characteristics of the ore, and developed preliminary mining plans. The host rock for the ore mineralization is related to sodic metasomatism and controlled by lithology and structure. The ore exhibits granoblastic texture, fine to coarse grain size, and the principal uranium minerals are uraninite, and, in minor quantities, pitchblende and uranophane. The solubility is over 90% of the U 3 O 8 contained, with an average acid consumption of 35 Kg per ton of ore treated. This paper presents a brief description of the main ore deposits and touches on their general characterisitcs. As an example, the deposit 'Jazida Cachoeira' is dealt with in greater detail, since this deposit is considered in the present context to be the most important one in the province. (Author) [pt
Calc-sodic zoning in rocks from Lagoa Real uranium Province, state of Bahia, Brazil
International Nuclear Information System (INIS)
Raposo, C.; Matos, E.C. de; Brito, W. de
1984-01-01
Preliminary studies of the lithogeochemistry, carried out on various deposits from the Uranium Province of Lagoa Real, show that in relation to the complex and multiphased processes of metasomatism, the sodic metasomatites are younger and were superposed on the potassic metasomatites. Such metasomatites developed in zones of extended and rejuvenated faults, after the transformation of the gnaisses, granitic rocks, amphibolites and ferruginous quartzites into various tectonites (mylonites, blastomylonites and protomylonites). The calcic metasomatism, subsequent to those phases, took place during the course of tectonothermal reactivations marking the termination of the principal metasomatic processes which aftected the rocks of Lagoa Real. The uranium deposit 'Jazida Laranjeiras', centrally situated in the Uranium Province of Lagoa Real is the only deposit in which the uranium mineralization is not intimately associated with the calcic metasomatism. Here, the ratio Na 2 O/CaO in the albitites is in the vicinity of 7,5 whereas in the other deposits this ratio decreases to values of about 1,5. The authors suggest calcic zoning (in the post-albitite phase) along the sigmoidal structure which localizes the uranium deposits, with an increase of the CaO content in the extreme parts of the structure - deposit 'Jazida Cachoeira' in the north and anomaly No. 02/12 in the south. Also suggested is the vertical zoning of calcium, whereby the intensity of the metasomatic phenomenon is increased towards the hanging wall side of the mieral parcel. (Author) [pt
Radon measurements in soils of Lagoa Real Uranium Province, BA: preliminary results
International Nuclear Information System (INIS)
Alves, James V.; Rocha, Zildete; Fuzikawa, Kazuo; Neves, J.M. Correia; Matos, Evando C. de
2007-01-01
The Cachoeira U mine in the Lagoa Real Uranium Province is the sole uranium producing mine in Brazil today. The necessity to increase ore reserves in the area is a reality, making any exploration efforts worthwhile to reach this objective. An exploration method based on radon detection in soil gas using the AlphaGUARD PQ2000PRO equipment was tested on two radiometric anomalies (no. 31 and no. 35) in the neighborhood of the mine. The results obtained indicated the technique as a helpful method for exploration of buried radioactive deposits. The method can not only discriminate thoron from radon but as a consequence indicate the original emanation source as well, making the method still more valuable in the search for uranium deposits. (author)
The uranium provinces of the Lagoa Real District-Bahia (Brazil)
International Nuclear Information System (INIS)
Geisel Sobrinho, E.; Raposo, C.; Alves, J.V.; Brito, W. de; Vasconcelos, T.G.
1980-01-01
The Lagoa Real Project from NUCLEBRAS represents one of the most important uranium provinces in Brazil today. The project is limited by the 42 0 00' - 42 0 30'W and 13 0 30' - 14 0 15'S geographic coordinates, covering an area of 4,540 square kilometres in the South-Central part of Bahia State. Since 1977, 13 radiometric anomalies have been detected. As part of the Archean basement, metasomatized and cataclastic metamorphic rocks outcrop in the area. The uranium mineralization occurs in albitite bodies parallel to its foliation and is represented by fine grained uraninite. Lying roughly in N-S direction the albitite bodies are tabular and elongated. Each albitite body may reach over 1 Km of extensoin, 100m of width, and 350m of depth. 207 Pb/ 206 Pb age determination indicated 820 my as the age of uraninite crystallization. An ore reserve of 27,000 ton of U 3 O 8 at an average grade of 0.15% U 3 O 8 has been determined following geologic, topographic, and radiometric survey over an area of 700 hectares and the completion of 160 drill-holes totalizing 23,000 metres. The potential uranium reserve of the Lagoa Real District has not as yet been properly evaluated because from the known orebodies only six have been sistematically investigated to date. (Author) [pt
Uraniferous albitites from the Lagoa Real Uranium Province, state of Bahia, Brazil
International Nuclear Information System (INIS)
Brito, W. de; Raposo, C.; Matos, E.C. de
1984-01-01
The Uranium Province of Lagoa Real is located in the region of Caetite, throughout the south-central portion of the state of Bahia. The basic chronostratigraphic units are the metamorphic rocks - granitic rocks and gneisses of the Archean basement - and cataclastic metasomatic rocks - albitites and quartzo-feldspathic lithologies of the lower Proterozoic. The albitites, host rocks for the uranium mineralization, occur regionally as numerous lenticular and discontinuos bodies arranged submeridionally according to two main alignments forming an arc, and are therefore called linear albities in allusion to similar features in Kasachstan, Russia, where they were first given this designation. The name albitite was employed to designate the metasomatites in which albitite dominates over the other minerals. The uranium mineralization consists of uraninite and pitchblende and is confined to the ore zones of those albitites containing aegirine, alkali-amphiboles, andradite, biotite and carbonates Furthermore, it displays lithologic-structural control, the morphology being controlled by the location of shear zones. This mineralization usually takes the shape of ore shoots which pitch in the direction and dip of the lineation. The authors describe the various types of albitites (mineralized or unmineralized) and their structural and petrographic characteristics, mode of occurence, geometry, metasomatic alterations, chemistry, uranium mineralization, as well as their genetic aspects. (Author) [pt
Uranium provinces and the exploration industry
International Nuclear Information System (INIS)
Hunter, J.; Michie, U.McL.
1988-01-01
There is little doubt that exploration by mining companies in established districts or 'provinces' has led to the discovery of substantial additional ore reserves. However, the competition for, and expenses of, land acquisitions in these known districts often prompts companies to search further afield. In some cases, new discoveries can merely be regarded as extensions of known provinces while others are located in completely new areas. Whether the explorers utilized concepts of metallogenic provinces in the course of such discoveries is questionable; rather, they would have sought the particular combinations of geological circumstances required by the model. Once a new deposit is found, however, the concept of a province, whether correct in that situation or not, is usually responsible for stimulating further activity. Recent examples of such behaviour are the Arizona Strip and NE Nebraska (USA) in provincial extensions and Roxby Downs, Lone Gull (NW Territories, Australia) and Lagoa Real (Brazil) in new areas. More routine and scientific application of metallogenic province theory by the uranium exploration industry would require evidence that not only the bulk of the world's uranium reserves but also the majority of the individual world-class deposits fall into geologically definable provinces. Such evidence should include the demonstration that particular areas of the Earth's crust had been enriched in uranium (with or without related elements) and that this enrichment had persisted through periods of crustal reworking and been responsible for concentrations of the metal ore deposits. The evidence described in the volume is critically reviewed in this context. (author). Refs, 4 figs
International Nuclear Information System (INIS)
Fuzikawa, K.; Alves, J.V.; Cuney, M.; Kostolanyl, C.; Poti, B.
1988-01-01
The Lagoa Real Uranium Province in the central-southern Bahia State, consisting of six deposits and several prospects, has a reserve of near one hundred tons of U 3 O 8 . The main lithological unit in the area is the Lagoa Real Complex which is formed by granites and gneisses derived from them. The unit overthrusts the Espinhaco metasediments the west. The Complex is the host of albities which may contain uraninite. The mineralization is manly associated with pyroxene and garnet. Petrographic and field relations indicate the overthrusting as the latest event, having left implants in the orebodies and their hosts. Fluid inclusion studies indicated fluids of different characteristics in the Espinhaco and the Lagoa Real Complex although they were similar in composition (carbonic and aqueous). The types inclusions detected are in agreement with the geologic processes suggested for the area: emplacement of the Sao Timoteo granite at 1.72 Ga; albitization and uranium mineralization at ∼ 1.4 Ga; and metamorphism at ∼ 0.49 Ga. The study is an example of fluid inclusion behaviour in a metamorphic process with very limited amount of fluids. (author) [pt
Potential uranium provinces in some arabian countries
Energy Technology Data Exchange (ETDEWEB)
Salman, A A [Nuclear materials authority, El Maadi, Cairo, (Egypt)
1995-10-01
This work represents an attempt to delineate potential uranium provinces in some Arabian countries using various related recognition criteria. Definition of these provinces is based on the available geologic and tectonic setting beside geochronological sequence and some geochemical characteristics. This trial would be of a great help for interchanging the ideas and necessary data for the development in the fields of uranium exploration and production. As a result of this study, a number of promising potential uranium provinces are recommended in some arabian countries. 5 figs.
Potential uranium provinces in some arabian countries
International Nuclear Information System (INIS)
Salman, A.A.
1995-01-01
This work represents an attempt to delineate potential uranium provinces in some Arabian countries using various related recognition criteria. Definition of these provinces is based on the available geologic and tectonic setting beside geochronological sequence and some geochemical characteristics. This trial would be of a great help for interchanging the ideas and necessary data for the development in the fields of uranium exploration and production. As a result of this study, a number of promising potential uranium provinces are recommended in some arabian countries. 5 figs
Lagoa Real uranium province - The History of an example
International Nuclear Information System (INIS)
Raposo, C.; Matos, E.C. de
1982-01-01
It is narrated a historic about the anomalies descovered in Lagoa Real province (BA), focusing the aspects related to geology, mineralization, drillings data and reserves evaluation. Geologic and radiometric maps of the anomalies are shown. (A.B.) [pt
International Nuclear Information System (INIS)
Goncalves, Rhaine Matos
2005-01-01
This work has as objective to contribute for the knowledge about the genesis of the Cachoeira uranium deposit (Lagoa Real Uranium Province, Bahia State, Brazil), characterizing pyroxenes (with emphasis in those associated with the uranium mineralization and those hosting inclusions) of the deposit and their associated inclusions. In function of the accomplished analyses, steps that should be followed to obtain and interpret data from fluid inclusions (FI), in the D09B XRF X-Ray Fluorescence Beam Line of the National Synchrotron Light Laboratory, Campinas, Brazil, have been described. The analyzed pyroxenes are augites, diopsides and aegirine-augites, and intermediate terms, for example between augite and diopside, were detected. They presented two and three phases fluid inclusions being some, possible, primary ones. The three phases FI could present a birefringent solid phase. The pyroxenes presented, also, solid inclusions. The analysis of some solid inclusions revealed that they were albites. These albites are, probably, previous to the pyroxene host mineral. The obtained results indicated that the studied pyroxenes are associated to an important phase of caleic metasomatism. These pyroxenes are not totally associated to the precipitation of the uranium. In the petrographic study of the samples, two types of plagioclase were identified, one very altered and other less altered. Synchrotron light is a powerful tool for analyze FI. It was verified that care in the preparation of the sample, such as the selection of near-surface FI, are very important to obtain reliable data. In the studies with synchrotron light only the vanadium was detected in larger amount in the area that contained FI (in pyroxene), in relation to the control area, due, mainly, to experimental factors. The presence of this element it is not easy to interpret. Additional studies, on solid and fluid inclusion in pyroxene, and in other minerals, will be important to understand the Cachoeira uranium
Sedimentary rocks Uranium in Cerro Largo Province
International Nuclear Information System (INIS)
Scaron, P.; Garau Tous, M.
1976-01-01
With the aim of the uranium minerals exploration has been carried out several studies by UTE technicians in Cerro Largo Province from 1968 to 1969. In uranium concentration has been found pyrite, phosphate, iron oxides and manganese in uranium. Furthermore in La Divisa Ore were studied concentration Uranium enrichment has been studied in La Divisa ore
International Nuclear Information System (INIS)
Souza, Aurelio da Silva de
2009-01-01
The Engenho deposit (anomaly 09) is south-eastern from Cachoeira Mine (anomaly 13), in the northern part of the Province. The uranium mineralization is associated to 'albitites' (over 70% of albite/oligoclase). Epidosites with uranium may also occur. The 'albitite' main minerals are pyroxene, gamet, albite/oligoclase feldspar, amphibole and biotite. Pyroxene, gamet, plagioclase, titanite and epidote are the minerals associated to the uranium mineralization. The fluids related to pyroxene, gamet and epidote are aqueous-saline, primary and with no carbonic phases and are constant, with small variations. They all present medium to high salinity (14 to 18wt% NaCl eq.), the higher values being related to pyroxene and the lower ones related to gamet and epidote. The fluids associated to albite/oligoclase, although aqua-saline and with no carbonic phases, show salinities much lower than in pyroxene, gamet and epidote, suggesting a intense dilution process indicating dilution toward the later minerals phases. The data suggest the pyroxene formation process occurring under a 3,5 kbar pressure condition which corresponds to approximately 10km depth. The dispersion on Th in albites, due probably to the overheating and non elastic increase in volume, precluded a reliable pressure calculation. The IF's microscopy m plagioclase gneiss (albitites host-rocks) suggests the probability of primary carbonic fluids associated to these minerals. The fluids with CO 2 showed in the gneiss maybe also be present in the albitites, probably as late or intergranular fluids. This assumption is based on the fact that signs of carbonic gases were shown during crushing tests. These tendencies suggest the occurrence of two albitization phases in this Lagoa Real area: one associated to a fluid composed by H 2 O + CO 2 + salts (in the gneiss host) and another (in the albitite) formed by an aqueous-saline phase. The data indicate the Brasiliano event as a thermal event without a predominant fluid
Mortimer Hills pegmatite uranium prospect: a Rossing-type uranium deposit in the Gascoyne Province
International Nuclear Information System (INIS)
Carter, J.D.
1984-01-01
A uraninite-bearing pegmatite of large dimensions in the Gascoyne Province is described. The pegmatite is compared with the Rossing uranium ore body of South West Africa and the two are shown to have common characteristics. Exploration recommendations for Rossing-type uranium mineralization in the Gascoyne Province are made
International Nuclear Information System (INIS)
Matos, Evandro Carele de; Franco, Jamyle Praxedes
2008-01-01
This work focus at the Uranium Province of Lagoa Real, notably considering the geological reserves of uranium already defined (100,000 tones of U 3 O 8 ) and the respective autonomy in providing raw material needed for making fuel elements. The province, based on geo economical parameters, supported by three main vectors (geological model/grade, mining/process route, investment/finance) has been elected to supply the required brazilian demand. Supplying of uranium for the brazilian power plants is in charge of Industrias Nucleares do Brasil - INB and is based on national production. Thus the Industrial Complex of Caetite has been implemented in the state of Bahia, aiming primarily to supply the needs of Angra 1 and Angra 2 power plants. This new production center has the capacity of producing up to 400 tones/yr. of U 3 O 8 . (author)
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Forman J. M. A.
2006-11-01
Full Text Available The search for uranium hos been going on in South America for the last 30 years and has led to discoveries of deposits in the following countries: Brazil, Argentine, Venezuela, Peru, Chile, Colombia and Ecuador. - In addition to the already known deposits in Brazil at Pocas de Caldas (Minas Gerais, Figueira (Parana and Quadrilatère Ferrifère (Minas Gerais, other deposits have been discovered at Itatiaia where the uranium is associated with phosphates, in the Lagoa Real region where the uranium is in microclinal gneiss, and in the Rio Preto region. Nearly 100 ore shows have been found in Lower Precarnbrian shales covered by Middle Precambrion quartzose sandstore. The industrial complexes of Pocas de Caldas and Fiqueira will start production respectively in 1980 and 1983. - In Argentina the mains deposits are in the Serra Pintada (Mendoza Province, at Los Adobes and Cerro Condor (Chubut Province and at Don Otto in the northern part of the country. Reserves now known and those being developed are very promising for the future. Pendant les 30 dernières années la recherche de l'uranium s'est poursuivie en Amérique du Sud et a abouti à la découverte de gisements dans les pays suivants : Brésil, Argentine, Venezuela, Pérou, Chili, Colombie et Équateur. . - Au Brésil, outre les gisements déjà connus de Poças de Caldas (Minas Gerais de Figueira (Parana et du Quadrilatère Ferrifère des Minas Gerais, d'autres gisements ont été découverts à Itatiaia où l'uranium est associé à des phosphates, dans la zone de Lagoa Real où l'uranium se trouve dans des gneiss à microcline et dans la région de Rio Preto. Près de 100 indices minéralisés sont reconnus dans les schistes du Précambrien inférieur recouverts par des grès quartzeux d'âge précambrien moyen. Les complexes industriels de Pocas de Caldas et de Figueira entreront en production respectivement en 1980 et 1983. - En Argentine, les principaux gisements se trouvent dans la
Uranium mineralization at Lagoa Real, BA, Brazil: the role of fluids in its genesis
International Nuclear Information System (INIS)
Prates, Sonia Pinto; Neves, Jose Marques Correia; Fuzikawa, Kazuo
2009-01-01
The Lagoa Real uranium province is situated in the central-south of Bahia state . Brazil and it is presently by far the most important and best known uranium occurrence in Brazil. Nowadays 34 anomalies are known in a 30 Km long and 5 km wide area. An open pit mine was open in Cachoeira Mine, in the north portion of the area, and it is the only uranium mine in operation in Brazil and even in South America as well. The uranium mineralization in the Lagoa Real uranium province occurs in metamorphic rocks named albitites, due to their albite content (over 70%). Uraninite is the main uranium mineral, followed by pechblende, uranophane, torbernite and other uranyl minerals. Uraninite occurs as tiny round and irregular crystals (20 a 30 μm) included or associated to mafic minerals, mainly pyroxene and garnet, and also to amphibole and biotite and sometimes to albite. Some secondary minerals such as, for instance, uranophane, torbernite and tyuyamunite are also found. The main albitites minerals from the Cachoeira mine (plagioclase, garnet, biotite, pyroxene, amphibole and titanite) were studied by means of Infrared Spectroscopy Techniques. Good results were obtained from small quantities of material (around 2 mg) and allowed the minerals identification, and also to know their composition (from the peak position) and to detect the presence of water molecules, which indicates an aqueous phase during the uranium formation, probably rich in Fluorine. (author)
International Nuclear Information System (INIS)
Santos, Camila M. dos; Rios, Francisco Javier; Amorim, Lucas E.D.; Palmieri, Helena E.
2017-01-01
The Lagoa Real Uranium Province (LRUP) is located in northwest of Bahia state and is the major uranium deposit of Brazil. Titanite is a common accessory mineral in rocks of LRUP and usually is part of uranium ore assemblage. Thirty three polished thin sections of F10 drill-hole located in Gameleira I deposit (anomaly 35) were petrographically studied and used for mineral chemistry study. Petrographically, titanite can be differentiated according to texture between granular and prismatic. Granular titanite is generally associated with magmatic assemblage (alkali feldspar hypersolvus granite) and it is present in some albitites (barren magnetite albitite). Prismatic titanite is restricted to albitite (garnet and mineralized magnetite albitite) and is associated with metamorphic assemblage. Microprobe analyses shows a trend from granites to mineralized albitites and do not cluster titanite by its texture, but by its host rocks. On the other hand, trace elements can distinguish titanite generation according to texture. Granular titanite is characterized by some highest high field strength elements (HFSE) values, like Hf, Pb, Th, U and HREE+Y, and the lowest V content. Vanadium has positive correlation with Zr/Hf ratio and inverse with U. Vanadium versus U relationship is inverse to the previously found by literature in LRUP what indicates that titanite was submitted to complexes processes of uranium loss after its crystallization. In addition, hafnium loss can be related to precipitation of hydrothermal zircon as it is strongly partitioned to this mineral. (author)
Energy Technology Data Exchange (ETDEWEB)
Santos, Camila M. dos; Rios, Francisco Javier; Amorim, Lucas E.D.; Palmieri, Helena E., E-mail: cms@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)
2017-11-01
The Lagoa Real Uranium Province (LRUP) is located in northwest of Bahia state and is the major uranium deposit of Brazil. Titanite is a common accessory mineral in rocks of LRUP and usually is part of uranium ore assemblage. Thirty three polished thin sections of F10 drill-hole located in Gameleira I deposit (anomaly 35) were petrographically studied and used for mineral chemistry study. Petrographically, titanite can be differentiated according to texture between granular and prismatic. Granular titanite is generally associated with magmatic assemblage (alkali feldspar hypersolvus granite) and it is present in some albitites (barren magnetite albitite). Prismatic titanite is restricted to albitite (garnet and mineralized magnetite albitite) and is associated with metamorphic assemblage. Microprobe analyses shows a trend from granites to mineralized albitites and do not cluster titanite by its texture, but by its host rocks. On the other hand, trace elements can distinguish titanite generation according to texture. Granular titanite is characterized by some highest high field strength elements (HFSE) values, like Hf, Pb, Th, U and HREE+Y, and the lowest V content. Vanadium has positive correlation with Zr/Hf ratio and inverse with U. Vanadium versus U relationship is inverse to the previously found by literature in LRUP what indicates that titanite was submitted to complexes processes of uranium loss after its crystallization. In addition, hafnium loss can be related to precipitation of hydrothermal zircon as it is strongly partitioned to this mineral. (author)
Application of NURE data to the study of crystalline rocks in the Wyoming uranium province
International Nuclear Information System (INIS)
Rush, S.M.; Anderson, J.R.; Bennett, J.E.
1983-03-01
The Wyoming uranium province study is a part of the National Uranium Resource Evaluation (NURE) program conducted by Bendix Field Engineering Corporation for the US Department of Energy. The ultimate objective of the entire project is the integration of NURE and other data sources to develop a model for a uranium province centered in Wyoming. This paper presents results of the first phase of the Wyoming uranium province study, which comprises characterization of the crystalline rocks of the study area using NURE hydrogeochemical and stream-sediment data, aerial radiometric and magnetic data, and new data generated for zircons from intrusive rocks in the study area. The results of this study indicate that the stream-sediment, aerial radiometric, aerial magnetic, and zircon data are useful in characterization of the crystalline rocks of the uranium province. The methods used in this project can be applied in two ways toward the recognition of a uranium province: (1) to locate major uranium deposits and occurrences, and (2) to generally identify different crystalline rock types, particularly those that could represent significant uranium source rocks. 14 figures, 8 tables
International Nuclear Information System (INIS)
Negrao, F.I.; Oliveira, G.G. de; Zanetti, J.C.; Cunha, R.P.P. da.
1990-01-01
The Uranium Province of Lagoa Real is situated in the central south of the State of Bahia and constitutes at the moment the second uranium resource of Brazil, containing, in several anomalies, as available resource, 93.850 ton. of U sub(3) O sub(8). The Uranio do Brasil S.A. develops a mine-industrial complex in this Province with the aim to extract and benefit uranium and intending to improve in 1992. The project is considered with high hazard, because involves te management of radioactive material, and becomes necessary an available of environmental impact, in accordance with CONAMA 001/86 and an active participation of the society. This paper aims to indentify the social and environmental impacts of this process, as a contribution of this important discussion. (author)
Uranium distribution in Brazilian granitic rocks. Identification of uranium provinces
International Nuclear Information System (INIS)
Tassinari, C.G.G.
1993-01-01
The research characterized and described uranium enriched granitoids in Brazil. They occur in a variety of tectonic environments and are represented by a variety granite types of distinct ages. It may be deduced that in general they have been generated by partial melting process of continental crust. However, some of them, those with tonality composition, indicate a contribution from mantle derived materials, thus suggesting primary uranium enrichment from the upper mantle. Through this study, the identification and characterization of uranium enriched granite or uranium provinces in Brazil can be made. This may also help identify areas with potential for uranium mineralization although it has been note that uranium mineralization in Brazil are not related to the uranium enrichment process. In general the U-anomalous granitoids are composed of granites with alkaline composition and granite ''sensu strictu'' which comprise mainly of syenites, quartz-syenites and biotite-hornblende granites, with ages between 1,800 - 1,300 M.a. The U-anomalous belongings to this period present high Sr initial ratios values, above 0.706, and high Rb contents. Most of the U-enriched granitoids occur within ancient cratonic areas, or within Early to Mid-Proterozoic mobile belts, but after their cratonization. Generally, these granitoids are related to the border zones of the mobile belts or deep crustal discontinuity. Refs, 12 figs, 3 tabs
International Nuclear Information System (INIS)
Wang, J.; Liu, J.; Zhu, L.; Qi, J. Y.; Chen, Y. H.; Xiao, T. F.; Fu, S. M.; Wang, C. L.; Li, J. W.
2012-01-01
The paper focused on the leaching behaviour of uranium (U) and thorium (Th) from uranium mill tailing collected from the Uranium Mill Plant in Northern Guangdong Province (CN)). Distilled water (pH 6) and sulphuric acid solution (pH 4 and 3) were used as solvent for the leaching over 22 weeks. It was found that the cumulative leach fraction from the mill tailing was 0.1, 0.1 and 0.7 % for U release, and overall 0.01 % for Th release, using distilled water, sulphuric acid solution of pH 4 and pH 3 as leaching agents, respectively. The results indicate that (1) the release of U and Th in uranium mill tailing is a slow and long-term process; (2) surface dissolution is the main mechanism for the release of U and Th when sulphuric acid solution of pH 3 is employed as the leaching agent; (3) both U and Th are released by diffusion when using sulphuric acid solution of pH 4 as the leaching agent and (4) U is released by surface dissolution, while Th is released by diffusion when using distilled water as the leaching agent. The implication for radiological risk in the real environment was also discussed. (authors)
International Nuclear Information System (INIS)
Zhao Jianbo; Yao Jian; Li Pilin
2012-01-01
The Presinian migmatitic complexes of Kangding Group distributed along 505 area of Datian, Panzhihua, Sichuan Province. Describing the geological features on 505 Uranium points, summarizing and analyzing the genesis of the migmatite complexes, overall structure, hydrothermal alteration, ore characteristics. It comes to a conclusion that the mineral type is migmatite uranium mineralization which is controlled by the migmatization and east-west structure. (authors)
Major uranium provinces: Yilgarn block and Gascoyne Province, Western Australia
International Nuclear Information System (INIS)
Butt, C.R.M.
1988-01-01
The Archaean Yilgarn Block and the adjacent Proterozoic Gascoyne Province, Western Australia, form the basement and source rocks for numerous occurrences of surficial uranium mineralization, the largest being the Yeelirrie deposit (35 million tonnes at 0.15% U 3 O 8 ). The mineralization, almost exclusively in the form of carnotite, has been deposited in the regolith and appears to be less than 1 Ma old, with some deposits still forming. The nature and distribution of the mineralization are controlled by basement and surface geology, geomorphology, hydrology and climate, being restricted to deeply weathered, semi-arid terrain with granitoid source rocks. A few small occurrences in the Gascoyne Province may be pedogenic in origin but the majority, in the north of Yilgarn Block, occur in unrejuvenated palaeodrainage channels now choked by colluvial, alluvial and chemical sediments. These sediments, which are aquifers for the present, predominantly sub-surface, drainage, can exceed 10-15 m. Uranium released from the weathering granitoids has been transported in groundwaters in uranyl carbonate complexes and precipitated as carnotite where, (i) concentrations of uranium and potassium have been elevated by evaporation and, (ii) dissolved vanadium has been oxidized to the 5-valent state. Precipitation is in calcretes and associated sediments in the drainage axes, in 'chemical deltas' where the drainages enter playas and in the playas themselves. This style of mineralization was first recognized in 1969-1970 as the result of investigations into the source of radiometric anomalies delineated by airborne surveys. The majority of discoveries have similarly been by radiometric surveys but hydrogeochemical surveys have promise and may become important in future search for blind mineralization and/or young deposits not in radioactive equilibrium. (author). 61 refs, 6 figs
Review of the NURE Assessment of the U.S. Gulf Coast Uranium Province
International Nuclear Information System (INIS)
Hall, Susan M.
2013-01-01
Historic exploration and development were used to evaluate the reliability of domestic uranium reserves and potential resources estimated by the U.S. Department of Energy national uranium resource evaluation (NURE) program in the U.S. Gulf Coast Uranium Province. NURE estimated 87 million pounds of reserves in the $30/lb U 3 O 8 cost category in the Coast Plain uranium resource region, most in the Gulf Coast Uranium Province. Since NURE, 40 million pounds of reserves have been mined, and 38 million pounds are estimated to remain in place as of 2012, accounting for all but 9 million pounds of U 3 O 8 in the reserve or production categories in the NURE estimate. Considering the complexities and uncertainties of the analysis, this study indicates that the NURE reserve estimates for the province were accurate. An unconditional potential resource of 1.4 billion pounds of U 3 O 8 , 600 million pounds of U 3 O 8 in the forward cost category of $30/lb U 3 O 8 (1980 prices), was estimated in 106 favorable areas by the NURE program in the province. Removing potential resources from the non-productive Houston embayment, and those reserves estimated below historic and current mining depths reduces the unconditional potential resource 33% to about 930 million pounds of U 3 O 8 , and that in the $30/lb cost category 34% to 399 million pounds of U 3 O 8 . Based on production records and reserve estimates tabulated for the region, most of the production since 1980 is likely from the reserves identified by NURE. The potential resource predicted by NURE has not been developed, likely due to a variety of factors related to the low uranium prices that have prevailed since 1980
Characterisation and genesis of the Singhbhum uranium province, India
International Nuclear Information System (INIS)
Mahadevan, T.M.
1988-01-01
The Singhbhum Uranium province is characterised by the late Archaean predominantly granitic Singhbhum Craton and the associated Proterozoic mobile belts, the boundaries of which are marked by major crustal dislocations. The Singhbhum craton had two-phase evolution during the time range 4000-2900 million years and its stabilisation around 2900 million years was marked by the emplacement of K-rich granitoids and the early crustal enrichment of uranium. Two distinctive types of uranium mineralisation occur in the Province - (i) the early Quartz Pebble Conglomerate (QPC) type and (ii) the later economically most significant shear-controlled hydrothermal type. The QPC type is confined to the cratonic volcano-sedimentary basins, characterised by basal fluvial high-energy deposits, near-continental volcanics and banded iron formations spanning the time band of 2900-2500 million years. The shear controlled hydrothermal mineralisation is predominantly developed in a 200 km-long arcuate zone of intense and deep tectonisation, acid-(?) alkaline-basic magmatism, hydrothermal activity and metallogenesis. This shear zone represents a belt of intense crust-mantle interaction. Uranium mineralisation is polyphasic, polymetallic. The mineralogy is complex and the chemistry of the ores is greatly influenced by the lithology of the host rocks involved in the shear. Part of the shear zone grazing the Dhanjori, predominantly volcanic supra-crustals is richer in U, Cu, Ni, Mo and also contains minor Bi, Au, Ag, Te and Se, while the western trans-Dhanjori sector of the shear zone characterised by schists and quartzites with lesser volcanic component is relatively poorer in these metals. The ore bodies in the trans-Dhanjori sector are more peneconcordant, gradational, stratabound and have spherical variograms, while those in the Dhanjori sector are transgressive, sharp, highly mobilised, vein type with Dewijsian variograms. A synthesis leads to the conclusion that uranium mineralisation is
Potential uses of genetic geological modelling to identify new uranium provinces
International Nuclear Information System (INIS)
Finch, W.I.
1982-01-01
Genetic-geological modelling is the placing of the various processes of the development of a uranium province into distinct stages that are ordered chronologically and made part of a matrix with corresponding geologic evidence. The models can be applied to a given region by using one of several methods to determine a numerical favorability rating. Two of the possible methods, geologic decision analysis and an oil-and-gas type of play analysis, are briefly described. Simplified genetic models are given for environments of the quartz-pebble conglomerate, unconformity-related vein, and sandstone types of deposits. Comparison of the genetic models of these three sedimentary-related environments reveals several common attributes that may define a general uranium province environment
International Nuclear Information System (INIS)
Fuzikawa, K.
1982-01-01
The geochemical conditions of the uraniferous carbonates of Lagoa Real province were studied using the fluid inclusions method and the isotopic determinations of the carbon and oxygen of these carbonates. (A.B.) [pt
Energy Technology Data Exchange (ETDEWEB)
Souza, Aurelio da Silva de
2009-07-01
The Engenho deposit (anomaly 09) is south-eastern from Cachoeira Mine (anomaly 13), in the northern part of the Province. The uranium mineralization is associated to 'albitites' (over 70% of albite/oligoclase). Epidosites with uranium may also occur. The 'albitite' main minerals are pyroxene, gamet, albite/oligoclase feldspar, amphibole and biotite. Pyroxene, gamet, plagioclase, titanite and epidote are the minerals associated to the uranium mineralization. The fluids related to pyroxene, gamet and epidote are aqueous-saline, primary and with no carbonic phases and are constant, with small variations. They all present medium to high salinity (14 to 18wt% NaCl eq.), the higher values being related to pyroxene and the lower ones related to gamet and epidote. The fluids associated to albite/oligoclase, although aqua-saline and with no carbonic phases, show salinities much lower than in pyroxene, gamet and epidote, suggesting a intense dilution process indicating dilution toward the later minerals phases. The data suggest the pyroxene formation process occurring under a 3,5 kbar pressure condition which corresponds to approximately 10km depth. The dispersion on Th in albites, due probably to the overheating and non elastic increase in volume, precluded a reliable pressure calculation. The IF's microscopy m plagioclase gneiss (albitites host-rocks) suggests the probability of primary carbonic fluids associated to these minerals. The fluids with CO{sub 2} showed in the gneiss maybe also be present in the albitites, probably as late or intergranular fluids. This assumption is based on the fact that signs of carbonic gases were shown during crushing tests. These tendencies suggest the occurrence of two albitization phases in this Lagoa Real area: one associated to a fluid composed by H{sub 2}O + CO{sub 2} + salts (in the gneiss host) and another (in the albitite) formed by an aqueous-saline phase. The data indicate the Brasiliano event as a thermal
Energy Technology Data Exchange (ETDEWEB)
Pokryshkin, V I; Bol' shov, V A; Kharitonova, R Sh; Bojko, V S; Berman, I B
1982-01-01
The comprative characteristic of uranium distribution regula-Arities in phosphorites of Arabian-African province and the Middle Asia is given. The data on radioactivity of phosphorites of Arabian-African province are borrowed for the published papers, the laboratory U and Th determinations are partially performed. Radioactivity of the Middle Asia phosphorites is studied by field radiometric and gamma spectrometric methods. Spatial uranium distribution in granular phosphorites has been determined by the f-radiography method. At the presence of general for granular phosphorites of both regions of increased radioactivity, uranium confinement to phosphate matter and identicity of uranium distribution in them, higher uranium content of Arabian-African province is pointed out. By K and Th quatities being due to a radioactivity unit, Arabian-African phosphorites are similar to authigenous phosphorites of the Middle Asia, by uranium content Arabian phosphorites are richer than the Asian ones. Allothigenous phosphorites differ from authigenous and African ones, relative (per radioactivity unit) uranium contents in them are 2.2-1.3 times less, while thorium and potassium 5.2-6.8 times higher. This fact reflects their poverty in phosphate matter and enrichment by terrigenous sandy-argillaceous material.
International Nuclear Information System (INIS)
Santos, Esau Francisco Sena
2006-01-01
In the present study, it was analyzed the surface concentrations of the natural radioelements K, U and Th, as well as the absorbed dose rate in air caused by gamma radiation from the Lagoa Real uranium province, which is located at the center southern portion of Bahia State and comprises an area of approximately 4.600 Km 2 . Data from the airborne gamma ray spectrometric survey of the region (Sao Timoeo Project) carried out in 1979, was used in this study. Besides, recent data of U, Th and absorbed dose rates from the Environmental Monitoring Program of the uranium concentration plant (URA), operated in the region by the Brazilian Nuclear Industries (INB), were used with the aim of inter compare the sampling points in the same geo referenced area. Imaging geo processing software's give support to frame maps of surface concentrations and ternary maps, as well as allow the integration of these with other themes (e.g. hydrology, geology, pedology) favouring the interpretation of geo environmental process from the radioactive cartography. Considering the whole study area, it was obtained the following mean values: absorbed dose rate in air (61,08 nGy.h -1 ), Potassium (1,65 % K) , Uranium (3,02 ppm eU) and thorium (18,26 ppm eTh). The geological unities bounding the uranium anomalies were placed in the areas characterized by the highest values of radioelements and, as expected, the major dose levels. The use of ternary maps coupled with the geology and hydrology allowed distinguishing the relationship between the surface distribution of natural radioelements and the geo environmental aspects, including the influence of the catchment in their transport and migration. (author)
International Nuclear Information System (INIS)
Galloway, W.E.
1985-01-01
Uranium ore bodies of the South Texas Uranium Province occur within the most transmissive sand facies of coastal-plain fluvial and shore-zone depositional systems. Host strata range in age from Eocene through Miocene. Ore bodies formed at the fringes of epigenetic oxidation tongues near intrinsic organic debris or iron-disulfide mineral reductants. Mineralized Eocene units, which include the Carrizo and Whitsett Sandstones, subcropped beneath tuffaceous Oligocene through early Miocene coastal plain sediments. Roll-front mineralization occurred because of this direct hydrologic continuity between an aquifer and a uranium source. Most ore occurs within coarse, sand-rich, arid-region, bed-load fluvial systems of the Oligocene through Miocene Catahoula, Oakville, and Goliad Formations. Host sediments were syndepositionally oxidized and leached. Reductant consists predominantly of epigenetic pyrite precipitated from deep, sulfide-rich thermobaric waters introduced into the shallow aquifers along fault zones. Mineralization fronts are commonly entombed within reduced ground. Modern ground waters are locally oxidizing and redistributing some ore but appear incapable of forming new mineralization fronts. (author)
Estimation grade of uranium from drill hole gamma logs
International Nuclear Information System (INIS)
Juliao, B.
1986-01-01
Radiometric grade of uranium deposits can be determined from drill hole gamma logs. The calculation of uranium oxide content can be obtained with good precision when the uranium ore is in radioactive equilibrium, containing only a small amount of thorium and no interference of potassium. This is the case of uranium ore from the Lagoa Real Uranium Province presented in this paper. The radioactive disequilibrium study in this province were made working over nine hundred samples analised with this special purpose in the CDTN-NUCLEBRAS laboratories. The data obtained indicated that the uranium in the ore is in perfect equilibrium with their daughter gamma emitters. Futhermore, the amount of Th and K is of no significance, so that the gamma counting represents exactly the uranium content of the ore. (author) [pt
Energy Technology Data Exchange (ETDEWEB)
Scaron, P; Garau Tous, M
1976-07-01
With the aim of the uranium minerals exploration has been carried out several studies by UTE technicians in Cerro Largo Province from 1968 to 1969. In uranium concentration has been found pyrite, phosphate, iron oxides and manganese in uranium. Furthermore in La Divisa Ore were studied concentration Uranium enrichment has been studied in La Divisa ore.
Radioactive pollution investigation and disposal of abandoned uranium mines in Jiangsu province
International Nuclear Information System (INIS)
Zhang Qihong; Zhao Fuxiang; Wang Lihua
2008-01-01
The environment influence of five abandoned uranium mines in Jiangsu province from 1950s to 1960s is introduced. By monitoring air absorbed dose rate of external exposure γ radiation, it is found that the pollution scope of No.1 abandoned uranium mine is the biggest in five abandoned uranium mines. The No. 2 and No. 3 mine areas has achieved the limit use after they were desposed. The radioactivity and the gamma nuclein in solid samples(slag, soil, silt) and liquid samples (the surface water, the well water)of No. 1 abandoned uranium mine were further analyzed and measured, the measured values are higher. The pollution of abandoned uranium mines still exists and diffuses after 30 years. According to the monitoring results and the analysis of pollution present situation, suggestions and measures are proposed for the pollution control. (authors)
The Mexican mesozoic uranium province: its distribution and metallogeny
International Nuclear Information System (INIS)
Bazan B, S.
1981-01-01
The distribution of uranium scattered in sedimentary terrains of the continental jurassic such as those found in the Tlaxiaco-Guerrero Basin encourage the outlook for uncovering extensive new deposits of strato-bound uranium belonging to the Mexican mesozoic in other structurally similar intercratonic basins. Stratographic and paleographic structural references define the simultaneous evolution of five sedimentary basins during the Mexican geotechtonic cycle: 1. the Tlaxiaco-Guerrero basin, 2. the Huayacocotla basin, 3. the Gulf of Sabinas basin, 4. the Chihuahua basin and 5. the Sonora basin. From the various lithostratographic formations in them we favourably infer the presence of intermountainous mesozoic concentrations of uranium sediments leached from crystalline precambric packets and from nevadian plutonites and volcanic rocks. During the metallogeny process described under the techtonic evolution of the Mexican structural belt, the presence is established of extensive terciary hydrothermal uranium deposits in the districts of Aldama, Chihuahua; Coneto-El Rodeo, Durango; Vizarron de Montes, Queretaro; Tlaucingo, Puebla; Los Amoles, Sonora; El Picacho, Sonora; Amalia Margarita, Coahuila; etc., scattered in sandstones and sinters of the continental mesozoic and shifted during the postorogenic phase of the Mexican geotectonic cycle. The extensive mesozoic province defined within the Mexican territory favourable to large deposits of uranium, scattered and strato-bound in triassic, jurassic and cretaceous sandstone and sinters, could resolve future demands for energetics within a modified philosophy and resourceful policy of regional mining. (author)
Decommissioning management of pit water at an uranium mine in Hunan Province
International Nuclear Information System (INIS)
Li Renjie
2002-01-01
The author introduces the influence of mining on groundwater at an uranium mine in Hunan Province, emphatically discusses the managing principles, methods and research works of pit water in decommissioning, and summaries sealing technique, construction management and the effect achieved in management of pit water
International Nuclear Information System (INIS)
Bower, M.B.; Needham, R.S.; Page, R.W.; Stuart-Smith, P.G.; Wyborn, L.A.I.
1985-01-01
The objective of this project is to help establish a sound geological framework of the Pine Creek region through regional geological, geochemical and geophysical studies. Uranium ore at the Coronation Hill U-Au mine is confined to a wedge of conglomerate in faulted contact with altered volcanics. The uranium, which is classified as epigenetic sandstone type, is derived from a uranium-enriched felsic volcanic source
International Nuclear Information System (INIS)
Wang Zhengqi; Wu Lieqin; Zhang Guoyu
2007-12-01
The methods following as field geological investigation, trace element geo- chemistry and isotope geochemistry were used in this project. Based on geological and geochemical characteristics of Xiaoshui uranium ore deposits in Zhongdong area, Xiazhuang ore-field, Guangdong province, it could be concluded that: (1) The Provenance of Cretaceous mantle is a enriched mantle; (2) Silicified zone-type and intersection-type uranium ore are distinctness in the metallogenic period and mineralization process, and main metallogenic period of Xiaoshui uranium ore-deposit is 73.5 Ma; (3) The sources of uranium mineralization substance derived from enriched mantle; and (4)The intersection-type high grade uranium deposits were controlled by substances derived from mantle (contain with U, CO 2 , F, et al), tracks of intersection of NWW-across with NNE-trending faults and lithology of diabase. (authors)
Energy Technology Data Exchange (ETDEWEB)
Zhengqi, Wang [East China Inst. of Technology, Fuzhou (China); [Beijing Research Inst. of Uranium Geology, Beijing (China); Lieqin, Wu [Institute No.290, CNNC, Shaoguan (China); Guoyu, Zhang [East China Inst. of Technology, Fuzhou (China)
2007-12-15
The methods following as field geological investigation, trace element geo- chemistry and isotope geochemistry were used in this project. Based on geological and geochemical characteristics of Xiaoshui uranium ore deposits in Zhongdong area, Xiazhuang ore-field, Guangdong province, it could be concluded that: (1) The Provenance of Cretaceous mantle is a enriched mantle; (2) Silicified zone-type and intersection-type uranium ore are distinctness in the metallogenic period and mineralization process, and main metallogenic period of Xiaoshui uranium ore-deposit is 73.5 Ma; (3) The sources of uranium mineralization substance derived from enriched mantle; and (4)The intersection-type high grade uranium deposits were controlled by substances derived from mantle (contain with U, CO{sub 2}, F, et al), tracks of intersection of NWW-across with NNE-trending faults and lithology of diabase. (authors)
International Nuclear Information System (INIS)
Liu Xiangguo
2003-01-01
According to scientific research and technical summing up reports, based on the field investigation, the possible problems of terrestrial heat and moderate-hot water during the exploitation of an uranium deposit in Jiangxi Province are discussed. The preliminary analysis and discussion on the distribution, distribution regularity, causes of formation and correlation of terrestrial heat and moderate-hot water at the uranium deposit are carried out
International Nuclear Information System (INIS)
Brynard, H.J.
1980-02-01
A sample of uranium-bearing phosphatic siltstone from Tsongnapan in the Northwestern Cape Province was investigated mineralogically. The siltstone consists of cyclically alternating apatite- and calcite spherulite-rich layers. The calcite content of the rock is 11,4% and the apatite content is 42,1%. The groundmass shows the presence of the following elements: Si, Ca, P, Fe, Mg, K, Al, Cu and Zn. Detrital quartz, albite and magnetite are mainly confined to calcite spherulitic layers. The uranium content of the siltstone is 1 120 ppm U 3 O 8 and the thorium content 638 ppm ThO 2 . Both uranium and thorium occur mainly in the apatite-rich groundmass and to a minor extent in subsidiary monazite and zircon. Laboratory-scale metallurgical tests showed that the uranium is almost wholly leachable by hydrochloric acid while sulphuric and acetic acid dissolve only a small percentage of the uranium with concomitant formation of calcium sulphate. The rock probably formed in a low-energy regime in a marine environment where apatite and calcite spherulites crystallised from a possibly colloidal state [af
Real-Time Speciation of Uranium During Active Bioremediation and U(IV) Reoxidation
International Nuclear Information System (INIS)
Komlos, J.; Mishra, B.; Lanzirotti, A.; Myneni, S.; Jaffe, P.
2008-01-01
The biological reduction of uranium from soluble U(VI) to insoluble U(IV) has shown potential to prevent uranium migration in groundwater. To gain insight into the extent of uranium reduction that can occur during biostimulation and to what degree U(IV) reoxidation will occur under field relevant conditions after biostimulation is terminated, X-ray absorption near edge structure (XANES) spectroscopy was used to monitor: (1) uranium speciation in situ in a flowing column while active reduction was occurring; and (2) in situ postbiostimulation uranium stability and speciation when exposed to incoming oxic water. Results show that after 70 days of bioreduction in a high (30 mM) bicarbonate solution, the majority (>90%) of the uranium in the column was immobilized as U(IV). After acetate addition was terminated and oxic water entered the column, in situ real-time XANES analysis showed that U(IV) reoxidation to U(VI) (and subsequent remobilization) occurred rapidly (on the order of minutes) within the reach of the oxygen front and the spatial and temporal XANES spectra captured during reoxidation allowed for real-time uranium reoxidation rates to be calculated.
Energy Technology Data Exchange (ETDEWEB)
Santos, Esau Francisco Sena
2006-07-01
In the present study, it was analyzed the surface concentrations of the natural radioelements K, U and Th, as well as the absorbed dose rate in air caused by gamma radiation from the Lagoa Real uranium province, which is located at the center southern portion of Bahia State and comprises an area of approximately 4.600 Km{sup 2}. Data from the airborne gamma ray spectrometric survey of the region (Sao Timoeo Project) carried out in 1979, was used in this study. Besides, recent data of U, Th and absorbed dose rates from the Environmental Monitoring Program of the uranium concentration plant (URA), operated in the region by the Brazilian Nuclear Industries (INB), were used with the aim of inter compare the sampling points in the same geo referenced area. Imaging geo processing software's give support to frame maps of surface concentrations and ternary maps, as well as allow the integration of these with other themes (e.g. hydrology, geology, pedology) favouring the interpretation of geo environmental process from the radioactive cartography. Considering the whole study area, it was obtained the following mean values: absorbed dose rate in air (61,08 nGy.h{sup -1}), Potassium (1,65 % K) , Uranium (3,02 ppm eU) and thorium (18,26 ppm eTh). The geological unities bounding the uranium anomalies were placed in the areas characterized by the highest values of radioelements and, as expected, the major dose levels. The use of ternary maps coupled with the geology and hydrology allowed distinguishing the relationship between the surface distribution of natural radioelements and the geo environmental aspects, including the influence of the catchment in their transport and migration. (author)
A review of Spanish uranium resources and recent developments in the province of Salamanca
International Nuclear Information System (INIS)
Gonzalez Granda, J.A.; Ruiz Sanchez-Porro, J.; Aranaiz Guezala, J. De
1997-01-01
Uranium exploration activities in Spain carried out during the 1950-1992 period, led to the discovery of a number of deposits in different geological environments. Presently there is only activity at the FE area in Salamanca province, where the only remaining mining centre is located. A new dynamic leaching processing plant with a capacity of up to 950 t U 3 O 8 t/year began operation in 1993, at FE mine. The development and planning of the mining in the open pits of ENUSA (province of Salamanca, Spain) under the present low market prices, has led to the implementation of a working scheme, based on the following concepts: Detailed knowledge of the distribution and quality of the mineralization by sufficiently close spaced drilling, with 3D positioning and grade estimation by deviation and gamma ray probing. Use of either geostatistical or arithmetical grade interpolation techniques, properly validated with production, adapted to the density of the information available. Economic optimization of the open pit, by means of the 3D Lerchs-Grossmann technique, as a guide for the final pit design. Calculation of the optimal pit shapes and recoverable resources under different price conditions. These techniques implemented by means of computerized data acquisition and processing systems, are used to face with versatility, the present economic conditions. A full review of the uranium deposits in the province of Salamanca is being carried out with these means. (author). 18 figs
International Nuclear Information System (INIS)
Peng Zhidong; Zhang Shuyi
2003-01-01
In Mesozoic-Cenozoic era, many medium-small-sized sedimentary basins had been formed in Yanbian draped-faulted region of Jilin Province. The basement of these basins is constituted of U-riched granite body produced during late Hercynian-early Yanshan period. Uranium-mineralization has been found in coal-bearing formation, oil-bearing formation and in tint layer of red formation. On the bases of analyzing of uranium source, geologic tectonic, paleoclimatology, paleogeography, hydrogeology and reconstruction, it is concluded that there is a prominent prospect to discover large in-situ sandstone-type uranium deposits in Yanji basins. (authors)
Energy Technology Data Exchange (ETDEWEB)
Santos, Esau Francisco Sena
2006-07-01
In the present study, it was analyzed the surface concentrations of the natural radioelements K, U and Th, as well as the absorbed dose rate in air caused by gamma radiation from the Lagoa Real uranium province, which is located at the center southern portion of Bahia State and comprises an area of approximately 4.600 Km{sup 2}. Data from the airborne gamma ray spectrometric survey of the region (Sao Timoeo Project) carried out in 1979, was used in this study. Besides, recent data of U, Th and absorbed dose rates from the Environmental Monitoring Program of the uranium concentration plant (URA), operated in the region by the Brazilian Nuclear Industries (INB), were used with the aim of inter compare the sampling points in the same geo referenced area. Imaging geo processing software's give support to frame maps of surface concentrations and ternary maps, as well as allow the integration of these with other themes (e.g. hydrology, geology, pedology) favouring the interpretation of geo environmental process from the radioactive cartography. Considering the whole study area, it was obtained the following mean values: absorbed dose rate in air (61,08 nGy.h{sup -1}), Potassium (1,65 % K) , Uranium (3,02 ppm eU) and thorium (18,26 ppm eTh). The geological unities bounding the uranium anomalies were placed in the areas characterized by the highest values of radioelements and, as expected, the major dose levels. The use of ternary maps coupled with the geology and hydrology allowed distinguishing the relationship between the surface distribution of natural radioelements and the geo environmental aspects, including the influence of the catchment in their transport and migration. (author)
International Nuclear Information System (INIS)
Galloway, W.E.
1982-01-01
The Oligocene-Miocene fluvial uranium host aquifers of the South Texas uranium province were deposited principally as syndepositionally oxidized sands and muds. Early intrusion of reactive sulfide-enriched waters produced large intrastratal islands of epigenetic sulfidic alteration, which contain isotopically heavy pyrite exhibiting unique replacement textures. The only known reservoir containing such sulfidic waters is the deeply buried Mesozoic carbonate section beneath the thick, geopressured Tertiary basin fill. Thermobaric waters were expulsed upward along major fault zones into shallow aquifers in response to a pressure head generated by compaction and dehydration in the abyssal ground-water regime. Vertical migration of gaseous hydrogen sulfide was less important. Repeated flushing of the shallow aquifers by oxidizing meteoric waters containing anomalous amounts of uranium, selenium, and molybdenum alternating with sulfidic thermobaric waters caused cyclic precipitation and oxidation of iron disulfide. Uranium deposits formed along hydrologically active oxidation interfaces separating epigenetic sulfidic and epigenetic oxidation zones. Multiple epigenetic events are recorded in imperfectly superimposed, multiple mineralization fronts, in regional and local geometric relations between different alteration zones, and in the bulk matrix geochemistry and mineralogy of alteration zones. The dynamic mineralization model described in this report may reflect processes active in many large, depositionally active basins
International Nuclear Information System (INIS)
Cupp, G.M.; Leedom, S.H.; Mitchell, T.P.; Kiloh, K.D.; Horton, R.C.
1977-10-01
Six uranium areas in Nevada were examined in a reconnaissance fashion to determine their favorability for uranium deposits. The favorable areas are: Virgin Valley, Humboldt County; northern Reese River Valley, Lander County; East Walker River, Lyon County; and Coaldale, Esmeralda County. Areas judged to be unfavorable are: Carol ''R'' prospect, Garfield Hills, Mineral County; and Meadow Valley (Panaca), Lincoln County. In the Virgin Valley area, the Canyon Rhyolite Formation contains as much as 27 ppM U 3 O 8 and is an excellent source rock. Uranium deposits in the underlying Virgin Valley Formation are small, but larger deposits may exist. The northern portion of the Reese River Valley contains several small uranium deposits but none of mineable grade or size. Rhyolitic volcanic rocks in the area contain above-average amounts of uranium, and larger deposits may lie beneath these potential source rocks. The East Walker River area may be part of a larger uranium province. Intrusive and extrusive rocks in the area contain above-average amounts of uranium, and low-grade supergene deposits were found. Large areas of potential source rocks and host rocks, and two small uranium deposits, were found in the Coaldale area. Many rhyolite plugs were also found. The Carol ''R'' prospect is an isolated uranium occurrence in Tertiary lacustrine rocks. Uranium deposits in Meadow Valley are in the Panaca Formation, a Pliocene lacustrine formation of varied lithology. The uranium deposits are small and low grade. It is unlikely that large-grade deposits will be found in this area
Study On The Choice Of Leaching System For Thanh My, Quang Nam Province Uranium Ores Treatment
International Nuclear Information System (INIS)
Than Van Lien; Nguyen Dinh Van; Tran The Dinh
2011-01-01
In order to implement the plan of peaceful uses of atomic energy, the Radioactive and Rare Earth Geology Division have been carried out the uranium ores exploitation project in Thanh My area of Quang Nam province since 2010. The treatment uranium ores samples is one of works of this project. In order to preparing for uranium ores samples treatment, the Institute for Technology of Radioactive and Rare Elements have been studied and have chosen the heap leaching method for Thanh My uranium ore treatment. The ore, which contained less than 0.07% U, was crushed to -1 cm before being placed in the heap. The acid consumption for this heap leach operation was approximately ranged 40 kg - 45 kg of H 2 SO 4 per tonne of ore, and oxidant 4 kg of MnO 2 per tonne of ore. The entire treatment cycle required 20-25 days, the recovery exceeded 80%, the leached tails contained less than 0.01% U. The experimental results were comparable with those obtained in the field scale heap leaching in the world. (author)
Uranium rich granite and uranium productive granite in south China
Energy Technology Data Exchange (ETDEWEB)
Mingyue, Feng; Debao, He [CNNC Key Laboratory of Uranium Resource Exploration and Evaluation Technology, Beijing Research Institute of Uranium Geology (China)
2012-07-15
The paper briefly introduces the differences between uranium rich granite and uranium productive granite in the 5 provinces of South China, and discusses their main characteristics in 4 aspects, the uranium productive granite is highly developed in fracture, very strong in alteration, often occurred as two-mica granite and regularly developed with intermediate-basic and acid dikes. The above characteristics distinguish the uranium productive granite from the uranium rich granite. (authors)
Uranium rich granite and uranium productive granite in south China
International Nuclear Information System (INIS)
Feng Mingyue; He Debao
2012-01-01
The paper briefly introduces the differences between uranium rich granite and uranium productive granite in the 5 provinces of South China, and discusses their main characteristics in 4 aspects, the uranium productive granite is highly developed in fracture, very strong in alteration, often occurred as two-mica granite and regularly developed with intermediate-basic and acid dikes. The above characteristics distinguish the uranium productive granite from the uranium rich granite. (authors)
International Nuclear Information System (INIS)
Dong Yongjie
1996-01-01
The author determines the content of uranium and organic carbon of part specimen of surrounding rocks and ores, which sampled from carbonate and black shale type uranium deposits in Xiushui, Jiangxi Province, and Tongcheng, Hubei Province. According to the analytical operation regulations of organic materials, extraction and separation of chloroform pitch is carried out. Internal relationships between uranium and organic derivative is discussed. The conclusion shows that: (1) certain co-relationship between U and organic carbon and chloroform extract is detected; (2) evolutionary processes of organic materials in the exogenetic uranium deposits are not all the same; (3) non-hydrocarbon is closely related to uranium, so it can be regarded as indicator of uranium gathering in exogenetic uranium deposits
International Nuclear Information System (INIS)
Guo Hua; Zhao Fengmin; Hu Shaokang; Chen Zuyi
2002-01-01
On the base of the study in the working area, a conclusion is made that there are 36 combined types of tectonic-material and 6 basic tectonic units. According to radioactive geochemical quantitative and qualitative factors, which are relevant to rock composition and geological formation, 5 radioactive geochemical provinces and 8 radioactive geochemical differentiation regions could be marked out. The working area contains three hydrogeological fold belts and two hydrogeological artesian basins. It could also be divided into 9 metallogenetic provinces or 30 metallogenetic regions, or 206 ore districts. On the other hand, the area could be divided into 2 uranium metallogenetic provinces, 2 potential uranium metallogenetic provinces and 3 uraniferous provinces, which contain uranium properties or potential uranium properties or uraniferous properties. The authors systematically summary the geological environment and indicators of prospecting and predicting of fluorine-molybdenum-uranium formation, hydromorphic uranium deposit formation and poly-genetic uranium deposit formation which contains uranium-coal model, uranium-asphalt model, uranium-sulfuret model, etc. The metallogenetic potential among Aerdan uranium province, Aoliaokema uranium province, Bulieya-Jiamusi-Xingkai potential uranium province and Xihuote-Alin uranium province are assessed. On this base, the authors delineate 23 uranium metallogenetic prospective areas needing further exploration efforts. 8 uranium metallogenetic prospective areas in China are marked out, which are areas of interest for searching for exogenetic and epigenetic sandstone uranium deposits
International Nuclear Information System (INIS)
Wilpolt, R.H.; Simov, S.D.
1979-01-01
Africa is not only known for its spectacular diamond, gold, copper, chromium, platinum and phosphorus deposits but also for its uranium deposits. At least two uranium provinces can be distinguished - the southern, with the equatorial sub-province; and the south Saharan province. Uranium deposits are distributed either in cratons or in mobile belts, the first of sandstone and quartz-pebble conglomerate type, while those located in mobile belts are predominantly of vein and similar (disseminated) type. Uranium deposits occur within Precambrian rocks or in younger platform sediments, but close to the exposed Precambrian basement. The Proterozoic host rocks consist of sediments, metamorphics or granitoids. In contrast to Phanerozoic continental uranium-bearing sediments, those in the Precambrian are in marginal marine facies but they do contain organic material. The geology of Africa is briefly reviewed with the emphasis on those features which might control the distribution of uranium. The evolution of the African Platform is considered as a progressive reduction of its craton area which has been affected by three major Precambrian tectonic events. A short survey on the geology of known uranium deposits is made. However, some deposits and occurrences for which little published material is available are treated in more detail. (author)
International Nuclear Information System (INIS)
Zhao Fengmin
2005-01-01
Chulute uranium metallogenetic region is situated in the northern part of North Hanggay Province in Mongolia. Geotectonically, it is located at the very western end of Mongolia-Transbaikal fold system. The granite with elevated uranium content is widely developed in this region, where the uranium content in the granite aged from Later Triassic to Early Jurassic ranges from 5 x 10 -6 to 6 x 10 -6 . Due to the neotectonic activation, quaternary palaeo-valleys that incised the basement were formed on the basement granite and were filled with organic matter-rich clastic sediments and basalt crusts. The palaeo-valley type uranium mineralization (Dajinhe, Bayaer and Shuer uranium occurrences) is discovered in the two palaeo-valleys which incised the granitoids. Of them, Shuer uranium occurrence has been studied more in detail. An ore-body with the thickness from 9.1 m to 19.75 m has been found in an area with the width of 500 m, and the uranium grade ranging from 0.01% to 0.05%. The uranium mineralization occurs in the bleached and limonitized grey loam and clayey soil and sand which bear rich calliferous plant debris and lamella of black mudstones. Coffinite is the uranium mineral. The uranium resources in Shuer deposit has been proven as 2500 t. The total predictive resources in above mentioned two palaeo-valleys reach as much as 15000-16000 t (P 2 ). The uranium mineralization in this region is characterized by young mineralization age and adjacent sources. The ore formation is possibly related to the surface thermal field which is originated from the eruption of the basaltic magmas. (authors)
International Nuclear Information System (INIS)
Amorim, Lucas Eustaquio Dias
2016-01-01
The Lagoa Real Uranium Province (PULR) is located in the center-south of the Bahia State, in the central part of Sao Francisco Craton and consists of an association of Paleoproterozoic meta-granites, alkali-gneiss, albitites, meta-leucodiorite and charnockites. This work has as objective the studies of the magmatic association, trying to understand its petrological and evolutionary meaning. For this purpose, representative bodies were sampled in order to develop unpublished studies of litogeochemistry, isotopes, geochronology and mineral chemistry. These analyzes were performed in: different preserved granitoid facies (Lagoa do Barro, Sao Timoteo, Juazeirinho and late pegmatitic phases), the meta-leucodiorites and charnockite. The data obtained using several modern methodologies, such as geochronology and mineral chemistry by LA-ICP-MS, provided results that allowed the characterization of two magmatic lithologies not described in the literature (Juazeirinho granite e late pegmatitic phases), and also a lithology preliminarily described (Lagoa do Barro granite). Moreover, these data contributed to elucidate the origin and meaning of the leucodiorite and charnoquito varieties, and made it possible to verify new compositional and mineral chemistry tendencies of Sao Timoteo granite. The data presented show that the studied granites were affected by albititization events (tardi or post-magmatic), which have different micro-chemical characteristics from the processes of albite formation related to the non-mineralized albitites bodies. Three albititization events were identified: a) An event that affected the granites characterized by the formation of albite with Rb and U, (b) Another event related to fluids associated with late pegmatitic bodies that formed albite with high levels of U, Rb and Ba, and partially affected the granites of the next pegmatoids portions; and (c) a final albititization event that caused the formation of the albite gneiss bodies, with albite
Uranium in Nova Scotia: a background summary for the uranium inquiry, Nova Scotia
International Nuclear Information System (INIS)
1982-01-01
Since the mid 1970's Nova Scotia has experienced increased exploration for a number of commodities including uranium. The exploration activity for uranium has resulted in discovery of significant occurrences of the element. It became obvious to the Government of Nova Scotia that a segment of the population of the Province is concerned about the potential hazards associated with the exploration, mining and milling stages of the uranium industry. Public concern has resulted in the appointment of a Commissioner under the Public Inquiries Act of Nova Scotia to inquire and make recommendations to the Governor-in-Council on all aspects of exploration, development, mining, processing, storage, waste management and transportation of uranium in any form. The regulation of mineral exploration and mining activities is carried out by the Nova Scotia Department of Mines and Energy through the Mineral Resources Act of the Province of Nova Scotia. The regulation of the special radioactive aspects involved in the mining and processing of uranium ore is the responsibility of the federal Atomic Energy Control Board. The purposes of this report is to: outline the history of uranium exploration in Nova Scotia; summarize the results of geological surveys by provincial and federal government agencies, universities and exploration companies which document the natural levels of radioactivity in the Province; briefly outline the physical and chemical characteristics of uranium and thorium which make these elements unique and a potential environmental and health concern; outline chronologically the steps taken by the Nova Scotia Department of Mines and Energy to monitor and regulate uranium exploration activities; classify the types of uranium deposits known to occur in Nova Scotia and describe their main geological features; outline the role of the Nova Scotia Department of Mines and Energy in the regulation of mining activities in the Province. The report is written for the interested
International Nuclear Information System (INIS)
Harding, J.; Forgay, B.; Gianoli, M.
1988-01-01
In recent years Saskatchewan, Canada has become the major site for the expansion of the world-wide uranium industry. Largely due to the higher concentration of ore in the province and reduced exploitation elsewhere, by 1984 Canada had become the world's leading non-communist producer of uranium. This expansion has remained one of the most controversial political and ecological issues in Saskatchewan for nearly a decade. What follows is a comprehensive bibliography on the Saskatchewan uranium mining inquiries that paralleled the growth of this industry in the province and on the northern and global impact of the uranium industry. It is the culmination of more than three years of research including in-depth content analysis of transcripts of uranium mining inquiries held in Saskatchewan between 1977-1980
Uranium mill tailings remedial action project real estate management plan
International Nuclear Information System (INIS)
1994-09-01
This plan summarizes the real estate requirements of the US Department of Energy's (DOE) Uranium Mill Tailings Action (UMTRA) Project, identifies the roles and responsibilities of project participants involved in real estate activities, and describes the approaches used for completing these requirements. This document is intended to serve as a practical guide for all project participants. It is intended to be consistent with all formal agreements, but if a conflict is identified, the formal agreements will take precedence
Uranium mill tailings remedial action project real estate management plan
Energy Technology Data Exchange (ETDEWEB)
1994-09-01
This plan summarizes the real estate requirements of the US Department of Energy`s (DOE) Uranium Mill Tailings Action (UMTRA) Project, identifies the roles and responsibilities of project participants involved in real estate activities, and describes the approaches used for completing these requirements. This document is intended to serve as a practical guide for all project participants. It is intended to be consistent with all formal agreements, but if a conflict is identified, the formal agreements will take precedence.
Production from new uranium mines a Cogema resources Saskatchewan perspective
International Nuclear Information System (INIS)
Pollock, B.
2001-01-01
The province of Saskatchewan is best known for the large flat tracts of land in the south that are primarily used for agricultural purposes. Less well known is the fact that the northern part of the province hosts the richest uranium mines in the world. In fact, to use a petroleum analogy, Saskatchewan has been referred to as the 'Saudi Arabia' of the uranium producing countries. The mining industry in Saskatchewan is a flourishing, high technology industry and supplies approximately one-third of the annual world primary production of uranium. The purpose of this paper is to examine the uranium mining industry in Saskatchewan and why this province stands alone as the dominant uranium producer in the world and will maintain that position into the foreseeable future. As well, an overview of the significant role played by COGEMA Resources in developing the Saskatchewan uranium industry will be undertaken. This company whose roots date back almost 40 years in the province, now holds significant interests in all four of the mines currently producing uranium. With investments of over one billion dollars (U.S.) in this province, COGEMA has established itself as a long-term player in the Saskatchewan Uranium Industry. (author)
International Nuclear Information System (INIS)
Oliveira, Lucilia A. Ramos de; Rios, Francisco Javier; Amorim, Lucas Eustaquio Dias; Souza, Aurelio da Silva; Prates, Sonia Pinto; Yardley, Bruce; Matos, Evando Carele
2009-01-01
The LA-ICP-MS technique is a good tool for mineral geochemical characterization. The technique has high spatial resolution, elevated sensibility, low detection limits and multi-elementary analysis possibility. Almost all chemistry elements can be analyzed by this methodology. Briefly, this methodology consists in vaporize the sample by Laser Ablation, which is dragged by argon into the Plasma where are created and accelerated the ions. They are separated by their mass/charge ratio into the Mass Spectrometer, being conveyed to a detector that convert the signals in specters. In this work LA-ICP-MS analyses were performed in two albitites thin sections, a mineralized and a non mineralized sample. Both samples are from the Lagoa da Rabicha Deposit, Uranium Lagoa Real Province, BA. From these analysis it was possible to chemically characterize the minerals present in the samples and better understand the trace elements on them. The results for plagioclase in both samples show that it is albite (NaAlSi 3 O 8 ). The albite from sample 200907-20 shows traces of strontium, lanthanum, cerium, neodymium, samarium and thorium in one crystal. The albite from sample 200907-23 has strontium with uranium, yttrium and lead in smaller quantities. The results obtained in this work are very important and contribute to a better understanding of the uranium origin in Lagoa Real deposits. (author)
Uranium deposit types and resources of Argentina
International Nuclear Information System (INIS)
Lopez, L.; Cuney, M.
2014-01-01
The uranium-related activities in Argentina begun in the 1950s and, as a result of the systematic exploration, several types of deposits have been discovered since then: volcanic and caldera-related, sandstone-hosted, vein spatially related to granite (intragranitic and perigranitic) and surficial. The deposits that have been the focus of the most important uranium exploitations are the ones that belong to the volcaniclastic type. These are localized in Permian formations associated with synsedimentary acid volcanism in the Sierra Pintada district (Mendoza province). The volcanic and caldera related type is also present in the Laguna Colorada deposit (Chubut province) located in the San Jorge basin (Cretaceous). Several important uranium mineralisations have been identified in Cretaceous fluvial sandstones and conglomerates, among which the most relevant is the Cerro Solo deposit (Chubut province) that corresponds to the paleochannel structure subtype. Other subtypes of sandstone model have been studied. For instance, the Don Otto deposit (Salta province), located in the Salta Group Basin (Cretaceous - Tertiary), belongs to the tabular U-V subtype. The roll front subtype can be also found in the Los Mogotes Colorados deposit (La Rioja province) which is hosted by Carboniferous continental sandstones. The uranium mineralisations in veins and disseminated episyenites within peraluminous leucogranites of the Sierras Pampeanas (Cordoba and San Luis provinces) represent other types of existing deposits. These granites are Devonian – Carboniferous and the related deposits are comparable to those from the Middle European Variscan. There are also other vein-type uranium deposits located in metamorphic basement in the periphery of high potassium calcalkaline granites (Sierras Pampeanas of Catamarca and La Rioja provinces), where the mineralisation control is mainly structural. The current uranium identified resources of the country are approximately 24,000 tU in the
Metamorphic history at Lagoa Real: implications for uranium mineralization
International Nuclear Information System (INIS)
Lobato, L.M.
1987-01-01
Metasomatism and attendant mineralization associated with shear zones have beem recently studied in detail by several investigators. It has emerged from these studies that whereas ground preparation by shearing is essential to the percolation of mineralizing solutions, the ultimate Loci of mineralization reflect chemical controls via fluid/rock interactions. Uranium mineralization at Lagoa Real can be conveniently understood through this perspective. (E.G.) [pt
Characteristics of uranium geological anomaly in Northern Guangdong province
International Nuclear Information System (INIS)
Wang Xinwu; Cheng Danping
2001-01-01
The geological anomaly characteristics of uranium deposit region in northern Guangdong are discussed on the aspects of uranium source, structure and thermal activity. Uranium deposits usually occur in the uranium-rich background field. Structure activity provides favourable places for the transportation and precipitation of uranium. Uranium deposits are formed in the central and edge of frequent thermal activity. The assembled entropy anomaly field is the synthetical display for above three anomaly. The biggest assembled entropy anomaly is the most favourable space field for forming uranium deposit
International Nuclear Information System (INIS)
Santos, Camila Marques dos
2016-01-01
In the northwestern portion of the Lagoa Real Uranium Province (LRUP), located in south-central Bahia, it is located one of the most promising uranium anomalies Brazil (an35, Gameleira I deposit), the reserves and proximity to the Cachoeira mine. Other anomalies of this sector (eg. 31 AN and AN34), are also considered strategic for the content of radioactive minerals and REE. The objective was to develop a study of a representative drill core of an35, where the main rocks PULR are present. The research focused on the mineralogical and chemical changes observed in the passages of a lithology to another, from the rock to the meta granitic albitites, through gneiss and transitional rocks, and making comparisons with similar lithologies sampled on testimonies of AN31 and 34. The granites are classified as hypersolvus coarse alkali-feldspar granite and are variably deformed. The main mineral assemblage in granites are perthitic orthoclase+hedenbergite+ quartz +hastingsite + biotite, and zircon, apatite, ilmenite and titanite are accessories. The reddening of these rocks are characterized by feldspars sericitization and hematitization and the presence of 'vazios'. The gneisses are mainly gray and reach milonitic to protomilonitics terms. These rocks have characteristics of subsolidus changes as swapped rims and metasomatic perthites. The tardi-magmatic association (amphibole+biotite) indicates final crystallization or late influx by superficial fluids resulting in an increase in water and volatiles, such as F and Cl in the system, which must also have carried rare-earth elementsGranites have geochemical affinity with A-type ferroan granite, A2, reduced and are post-collisional. Their patterns of incompatible elements and rare earths are comparable to Sao Timoteo Granite, but their petrographic features indicate that it is a less common granite facies. Albitites were classified as garnet albitites, magnetite albitites and biotite albitites. Contacts between
Doering, Che; Bollhöfer, Andreas
2016-10-01
This paper presents a database of radionuclide activity and metal concentrations for the Alligator Rivers Region (ARR) uranium province in the Australian wet-dry tropics. The database contains 5060 sample records and 57,473 concentration values. The data are for animal, plant, soil, sediment and water samples collected by the Environmental Research Institute of the Supervising Scientist (ERISS) as part of its statutory role to undertake research and monitoring into the impacts of uranium mining on the environment of the ARR. Concentration values are provided in the database for 11 radionuclides ( 227 Ac, 40 K, 210 Pb, 210 Po, 226 Ra, 228 Ra, 228 Th, 230 Th, 232 Th, 234 U, 238 U) and 26 metals (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, Rb, S, Sb, Se, Sr, Th, U, V, Zn). Potential uses of the database are discussed. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.
International Nuclear Information System (INIS)
Stear, W.M.
1980-12-01
Most of the Beaufort Group uranium deposits in the southwestern Karoo are located near the contact of the Abrahamskraal Formation and the Teekloof Formation within a stratigraphic interval of about 500 meters. Rocks of the Lower Beaufort uranium province in the Beaufort West study area occur in thick, fining upwards megacyclic sequences, each of which consists of an arenaceous zone overlain by an argillaceous zone. The morphology and internal geometry of selected channel sandstone bodies are described in plan and cross-section. Lateral and vertical profile diagrams are used to illustrate the salient features of fluvial style in the Abrahamskraal Formation and to compare these characteristics with recognised fluvial facies models. The Abrahamskraal Formation provides a local facies model of an ancient, interior drainage system characterised by a continuously shifting, ephemeral fluvio-lacustrine complex. Semi-arid climatic conditions in the depositional environment promoted the formation of uranium mineralization. The geologic structure and stratigraphy of the area, the facies and their distribution, the channel facies association as well as the geometry of the channel sandstone bodies and the interchannel facies association are discussed
International Nuclear Information System (INIS)
Nicolli, H.B.; Gamba, M.A.
1979-01-01
Geochemical characteristics of ground waters related with lixiviation, transport and precipitation of uranium in the Conlara river valley (provinces of San Luis and Cordoba (Argentina)) are studied. Anions and cations' distributions, together with hardness, specific conductivity, pH, Eh, and uranium and vanadium contents, have been studied. Those parameters characterize four hidrogeochemical facies along an E-W profile: a calcic strong bicarbonate facies, an alkaline-calcic bicarbonate facies, an alkaline sulfate facies, and a strong alkaline sulfate facies. An ''Interphase zone'' (transition from bicarbonate water to sulfate water), where changes in composition may define a geochemical environment capable of UO2 precipitation, has been determined. The chemical-Thermodynamic studies give a dominance of UDC and UTC complexs ions (even in sulfate waters), so they represent the 99% of present ions. Besides, the calculated values required for equilibrium with uraninite or carnotite resulted much greater than those obtained in the performed experiments. It means that the precipitation of those minerals requires either the presence of greate amounts of uranium or vanadium, or a reducing environment with Eh values smaller than the observed ones. Finally, the steps to be taken in future investigations are suggested in view to a drilling plan where: 1) Priority to the ''Interphase zone'' areas is given. 2) The deepest aquifers in Tertiary sediments of the basin have to be reached in order to get the convenient environmental conditions (i.e. smallest Eh values) for uranium or uranium-vanadium precipitation. (author) [es
Geology and structure of major uranium-bearing zones in India and their exploration
International Nuclear Information System (INIS)
Nagabhushana, J.C.; Vasudeva Rao, M.; Sahasrabudhe, G.H.; Krishnamoorthy, B.; Suryanarayana Rao, C.; Rama Rao, Y.N.
1976-01-01
Radiogeologic, lithostratigraphic, tectonic, and crustal evolutionary considerations have enabled the recognition of three major uranium provinces in India: the Singhbhum Province in the north-east; the Rajasthan Province in the north-west; and the Madhya Pradesh Province in central India. The paper describes the salient features of the three uranium provinces, with particular emphasis on their structural set-up, magmatectonics, and the controls of uranium mineralization, and presents a few recent case histories of individual deposits (Bagjata and Turamdih in Singhbhum, and Dhabi-Dumhat in Madhya Pradesh) discovered by integrated exploration techniques. The three uranium provinces are related to major deep-seated faults: the Singhbhum Province lies at the arcuate north-east end of the deep fault of the Eastern Ghats; the Rajasthan Province parallels the great boundary fault; and the Madhya Pradesh Province aligns with the Mahanadi-Son rift system. Some of the plausible explanations for these remarkable features are: localization of uranium ore during episodes of crustal fracturing in Precambrian times; reactivation and rejuvenation of favourable basement structures; and the role of local 'hot spots' (aided by compressional and vertical tectonics) in crustal zones anomalously enriched in the heat-producing elements. Uranium exploration strategy in India during the last three decades reveals two significant trends - the application of conventional radiometric techniques during the period 1950-65; and introduction of sophisticated methodology comprising non-radiometric geophysical techniques, emanometry, aerial and car-borne gamma-ray spectrometry, geochemical surveys, and photogeological techniques as supplements to conventional radiometry, during the period 1965-75. It is concluded that extension of such integrated exploration techniques to favourable virgin terrains in India would lead to newer and richer uranium ore discoveries. (author)
Uranium geochemistry, mineralogy, geology, exploration and resources
International Nuclear Information System (INIS)
De Vivo, B.
1984-01-01
This book comprises papers on the following topics: history of radioactivity; uranium in mantle processes; transport and deposition of uranium in hydrothermal systems at temperatures up to 300 0 C: Geological implications; geochemical behaviour of uranium in the supergene environment; uranium exploration techniques; uranium mineralogy; time, crustal evolution and generation of uranium deposits; uranium exploration; geochemistry of uranium in the hydrographic network; uranium deposits of the world, excluding Europe; uranium deposits in Europe; uranium in the economics of energy; role of high heat production granites in uranium province formation; and uranium deposits
International Uranium Resources Evaluation Project (IUREP) national favourability studies: India
International Nuclear Information System (INIS)
1977-08-01
Physiographically India has a total area of 3,268,010 km 2 in three distinct regions. 1. The Peninsular shield in the south with an area of 823,310 km 2 . 2. The Himalayan mountain system with an area of 1,797,200 km 2 . 3. The Indo-Gangetic alluvial plain with an area of 647,500 km 2 . The three presently recognised major uranium provinces in India are: 1. The Singhbhum uranium province; 2. The Rajasthan uranium province, 3. The Madhya Pradesh uranium province. The Atomic Minerals Division of the Department of Atomic Energy has carried out a vigorous exploration programme since 1949 but despite their efforts a great deal of ground has still to be explored. At present, structurally controlled deposits account for most of the uranium resources of India. Uranium occurrences and deposits have been outlined in (1) Vein type deposits (the Singhbhum belt), (2) Conglomerate (Karnataka and Udaipur area, Raiasthan), (3) Sandstones (Madhra Pradesh and Swaliks, Himachal Pradesh, (4) Others such as carbonatites, marine phosphates, etc, (Mussorrie - Sahasradhara In Uttar Pradesh and Chatterpur-Saucur in Madhya Pradesh), (5) By-product Uranium in copper tailings and beach sands. India's total resources are listed as 52,538 tonnes uranium (68,300 short tons U 3 O 8 ) with additional resources from monazite of 12700 tonnes uranium. In view of the wide geological favourability, the many types of occurrences already known and the vast areas of unexplored ground it is estimated that the Speculative Potential may be between 150,000 and 250,000 tonnes uranium which is Category 5. (author)
An Overview of Uranium Exploration Strategy in India
Energy Technology Data Exchange (ETDEWEB)
Chaki, A., E-mail: director.amd@gov.in [Atomic Minerals Directorate for Exploration and Research, Hyderabad (India)
2014-05-15
Uranium exploration in India dates back from 1949 and the first mineralized area was located in the early 1950s in Singhbhum Shear Zone (SSZ), eastern India. Since then, a number of potential and promising uranium provinces have been established in India. The potential uranium provinces include SSZ, Dongargarh, Aravalli, Siwalik belt, Mahadek basin, south-western and northern parts of Cuddapah basin, North Delhi Fold Belt, Bhima and Kaladgi basins. The promising uranium provinces are Proterozoic Chhattisgarh, Indravati, Gwalior, Vindhyan, Shillong basins, Gondwana basins of Central India and semi-arid regions of western Rajasthan. With the establishment of large tonnage-high grade Lower-middle Proterozoic unconformity deposits in Canada and Australia, there was a paradigm shift in the exploration strategy towards the Proterozoic basins of India. The discovery of unconformity related uranium mineralisation in the northern part of Proterozoic Cuddapah basin in southern India in 1991 and discovery of few deposits in the province has opened the avenues for finding of similar deposits in Cuddapah and other 13 Proterozoic basins in India. As a sequel, Proterozoic Bhima basin in southern India has been recognized as a potential target for uranium mineralization, where a low tonnage medium grade deposit has been established and mine development works are in progress. Sustained exploration efforts in other Proterozoic basins have yielded success in a few basins such as Deshnur area in Kaladgi Basin of southern India. Considerable uranium resources have been established in Proterozoic Cuddapah and Bhima basins. Apart from northern parts of Cuddapah and Bhima basins, areas in the southwestern part of Cuddapah basin for stratabound type, where a mine is under construction; Proterozoic Kaladgi basin for vein type; Cretaceous Mahadek basin for sandstone type and the North Delhi Fold belt for vein type of mineralization have been prioritized as potential areas for exploration
Initial results of uranium prospecting in Baluchistan, Iran
International Nuclear Information System (INIS)
Hemmer, C.
1980-01-01
Uranium prospecting in Baluchistan, SE-Iran, led to the discovery of uranium occurrences at the northern rim of the undrained Jaz Murian Depression. All known uranium occurrences are epigenetic local enrichments of no economic significance which originate from mobilization of uranium from Tertiary acidic magmatic rocks. The great extent of both the uranium source and the host areas indicate significant uranium mobilization and a possible economic potential for the area as a uranium province in the future. (orig.) [de
Cachoeira Uranium Deposit, Lagoa Real, Bahia, Brazil – Kinematic, compositional and fluid evolution
International Nuclear Information System (INIS)
Pires, F.; Miano, S.
2014-01-01
The Cachoeira uranium albitite-type deposit occurs in a steep dip shear zone aligned with several other similar uranium deposits in the Lagoa Real Province. Uranium resources are estimated as about 90,000 t U_3O_8 [~76,000 t U] grading 2500 ppm U_3O_8 [~2100 ppm U]. Uraniferous albitite occupies a 15 m-thick strongly mylonitized shear zone structurally enclosed within “zebra” biotite gneiss. Uranium albitite mineralization forms cigar-shaped (prolate) and secondarily pancake-shaped (oblate) bodies composed of albite-hornblende-garnet-uraninite-magnetite ore grading to quartz-free skarntype rock with fluorite-kyanite-calcite-quartz concordant veins and pockets formed by late hydrothermal process. Brown chalcedony was the latest mineral to form. Fine-grained, disseminated uraninite is distributed and concentrated in the mafic portions of the gneiss consisting of hornblende andradite- sphene-apatite-epidote forming 30% and albite portions consisting of 70% of the albitite, which allows its gravitational treatment, thus decreasing acid leaching. While the host rock was severely affected by K-metasomatism the uraninite zone was deposited together with hornblende by Na- and Ca-metasomatism. Another reaction involves garnet crystallization exclusively together with uraninite, which liberates sílica and oxygen, differently from previous reaction which consumes silica and oxygen. Both reactions involve magnetite. The destabilization of biotite at the ore zone implies in the formation of GSPO-biotite overgrowing the LPO-biotite previously formed at host rock, due to the excess of K in the system. Magnetite is absent. The reaction represents the K-metasomatism at the host zebra gneiss: biotite + plagioclase + pyroxene + UO_2Cl"+ + Ca_2"+ = hornblende + uraninite + kyanite + quartz. The excess of Ca is allocated in the sphene, apatite and epidote structures. Consumption of Ca results in rutile deposition. As fluid composition was complex F and CO_2 were enriched in the
Energy Technology Data Exchange (ETDEWEB)
Williams, R M
1976-01-01
Evidence of expanding markets, improved prices and the short supply of uranium became abundantly clear in 1975, providing the much needed impetus for widespread activity in all phases of uranium operations. Exploration activity that had been at low levels in recent years in Canada was evident in most provinces as well as the Northwest Territories. All producers were in the process of expanding their uranium-producing facilities. Canada's Atomic Energy Control Board (AECB) by year-end had authorized the export of over 73,000 tons of U/sub 3/0/sub 8/ all since September 1974, when the federal government announced its new uranium export guidelines. World production, which had been in the order of 25,000 tons of U/sub 3/0/sub 8/ annually, was expected to reach about 28,000 tons in 1975, principally from increased output in the United States.
Evaluation of environmental impacts arising from uranium extraction in Lagoa Real Bahia
Energy Technology Data Exchange (ETDEWEB)
Oliveira, Suzicleide L.; Thibes, Ronaldo; Campos, Simara S., E-mail: suzilopes@ig.com.br, E-mail: thibes@uesb.edu.br, E-mail: simaracampos@gmail.com [Universidade Estadual do Sudoeste da Bahia (UESB), Itapetinga, BA (Brazil)
2013-07-01
Since the beginnings of the industrial era, there has been an increasing use of fossil fuels, causing a rising of about 30% in the level of carbon dioxide concentrations and, consequently, elevating the global temperature. In the present days, we witness a huge worldwide concern about the generation of energy without emitting polluting gases responsible for the global warming, the so called clean energy. In this way, nuclear energy has reemerged as an important efficient means for generating domestic and industrial energy without producing the toxic greenhouse effect gases. Brazil is one of the current highest economic developing countries, with various internal sectors demanding more and more new technologies and energy consumption. Although traditionally Brazil has lain mainly on hydric resources, nuclear energy appears as real option in the current scenario. In the present work we analyse uranium extraction and processing in the Brazilian Region of Lagoa Real Bahia. In the recent literature, there has appeared some localized works, analyzing environmental impacts arising from the uranium extraction in that region. Based on data collection and analysis of soil, water and teeth, these works represent a first effort in the environmental impacts issue. Building upon published technical results we aim at a global understanding of the problem. Considering such different data sets, we look for global answers relating general aspects of the uranium extraction in the region. We present a comparative study, stressing connections and pointing ou different aspects of the common environmental issue. (author)
Evaluation of environmental impacts arising from uranium extraction in Lagoa Real Bahia
International Nuclear Information System (INIS)
Oliveira, Suzicleide L.; Thibes, Ronaldo; Campos, Simara S.
2013-01-01
Since the beginnings of the industrial era, there has been an increasing use of fossil fuels, causing a rising of about 30% in the level of carbon dioxide concentrations and, consequently, elevating the global temperature. In the present days, we witness a huge worldwide concern about the generation of energy without emitting polluting gases responsible for the global warming, the so called clean energy. In this way, nuclear energy has reemerged as an important efficient means for generating domestic and industrial energy without producing the toxic greenhouse effect gases. Brazil is one of the current highest economic developing countries, with various internal sectors demanding more and more new technologies and energy consumption. Although traditionally Brazil has lain mainly on hydric resources, nuclear energy appears as real option in the current scenario. In the present work we analyse uranium extraction and processing in the Brazilian Region of Lagoa Real Bahia. In the recent literature, there has appeared some localized works, analyzing environmental impacts arising from the uranium extraction in that region. Based on data collection and analysis of soil, water and teeth, these works represent a first effort in the environmental impacts issue. Building upon published technical results we aim at a global understanding of the problem. Considering such different data sets, we look for global answers relating general aspects of the uranium extraction in the region. We present a comparative study, stressing connections and pointing ou different aspects of the common environmental issue. (author)
International Nuclear Information System (INIS)
Xia Yuliang; Rong Jiashu; Lin Jinrong; Zheng Maogong; Wen Xiyuan
1993-05-01
Based on the systematic studies of petrology, geochemistry and isotope geochronology, the Early Precambrian metamorphic complex in Northern Hebei province of China can be divided into three different series, i.e. granulite series, khondalite series and amphibolitic-felsic rock series. The so called 'magmatic granitoids' in that area are actually some magmagranites with different ages and different geneses, and they are not formed by migmatization. Up to now, the discovered Huaian complex which was formed in 3.5 Ga ago is the oldest nuclear area in the northern margin of North-China Platform. The granulite series, khondalite series and amphibolitic-felsic rock series belong to Early Archaean (>3.0 +- 0.1 Ga), Middle Archaean (>2.7 +- 0.1 Ga) and Later Archaean (>2.4 +- 0.1 Ga) respectively. The geological time scale of the Early Precambrian for Northern Hebei Province has been built. According to the synthetic analyses of various factors there is no prospect of uranium mineralization in the ancient terrain. However, the Mesozoic volcanic basins covering over the Hercynian Period granites would be main goal for looking for large uranium deposits in north part in that area
International Nuclear Information System (INIS)
Zhou Yulong; Yang Song
2012-01-01
Started with the spatial distribution of nappe structure, the geologic features are discussed and its effect on uranium mineralization in systematically summarized for Xiangshan ore-field in the middle of Jiangxi Province. The nappe structure not only formed a 'cross-over' lithologic combination which creates a network system which can connect, transport, migrate the mineralized matter, but also formed some close or semi-close geologic setting beneath the nappe which can act as the store ore shield space for the mineralized liquid to form uranium deposit. The mineralization is concentrated at the varied place of occurrences or shape of sub-volcanic rocks and the intersection of concealed overthrust and NE strike basic fractures. (authors)
International Nuclear Information System (INIS)
Wang Wenguang; Tao Quan; Zhang Shouben
1997-10-01
Regional geologic characteristics, metallogenetic conditions and prospects of uranium ores in the central part of the Eastern Liaoning Province of North China is studied systematically. It demonstrates that the Archaean basement of the study area consists of a special type of granite-greenstone belts in China. It is called the granite-greenstone belts of the Liaoning-model, in which the granitic rocks are mainly migmatitic granite and granite-gneiss of migmatitic genesis. The greenstone belts in this area have undergone strong metamorphism. Large amounts of Precambrian geochronological studies have been made with U-Pb isotopic method on zircon; and a new Precambrian geologic time scale has been established. It is also proved that multistage activation of the Early Precambrian basement and the proto-platform took place in Early Proterozoic. Emphases are laid on uranium and thorium abundances and their variations as well as primary uranium contents of rocks in the granite-greenstone terrain and those of the Lower Proterozoic. At the same time, uraninite as accessory mineral in granitic rocks is found to exist more or less. Early Precambrian strata and many kinds of mineral deposits occurring in the strata are in origin chiefly of syngenetic hot brine sedimentation and of submarine extrusive gas-hydrothermal sedimentation superimposed by metamorphism. Metallogenetic features and models of various types of uranium deposits are studied emphatically and compared with similar large deposits abroad. In addition, overall synthetical appraisals are made for this area; and on this basis, prospecting directions and favourable sections of uranium metallization are suggested. (4 refs., 4 tabs.)
International Uranium Resources Evaluation Project (IUREP) national favourability studies: Sweden
International Nuclear Information System (INIS)
1977-11-01
Sweden, covers an area of approx. 450 000 square kilometers. It has a population of 8 millions. With few exceptions in the northern part the access can be regarded as good. A dense network of motorroads and railroad exists. The results obtained by the exploration works combined with other available geo-information permit a separation of two principal uranium provinces in Sweden. The first one is confined to sediments of Upper Cambrian and Lower Ordovician which appears in Southern Sweden and along the border of the Caledonian mountain range in Central Sweden. The uranium occurrence are stratiform, of blackshale type which occurs in the Peltura zone of Upper Cambrian or they are associated to a phosphatite-bearing unit of Lower Ordovician overlying the Cambrian shale formation. The distribution of uranium in Upper Cambrian rocks is in general dependant on their lithology which itself is related to the paleography. This conditions explain relatively higher uranium content of the shale from Billigen.The potential resources of the province are estimated at about 1 million tonnes uranium. The second uranium province, called Arjeplog-Arvidsjaur, situated immediately south of the Arctic circle, comprises one deposit - Pleutajokk - and a group of more than twenty occurrences of similar characteristics and age (1 700 - 1 800 my.). The results of the past exploration have shown that uranium is present in different types of rocks. Because of the presence of uranium in many of the pegmatites the possibility of the formation of large low grade deposits should be tested. Favourable areas are those regions where the geological conditions are similar to the geology of the Grenville province in Canada or the Damara belt of SW-Africa. Special studies are recommended on this subject
Canada's deadly secret : Saskatchewan uranium and the global nuclear system
Energy Technology Data Exchange (ETDEWEB)
Harding, J.
2007-07-01
Although Canada has a reputation for its support of multilateralism and international peacekeeping, it has provided fuel for American and British nuclear weapons, and continues to provide uranium fuel for nuclear reactors and power plants throughout the world. This book provided a detailed outline of Canada's involvement in uranium mining in Saskatchewan, the largest uranium-producing region in the world. The ways in which Canada has been complicit in the expansion of the global nuclear system were examined. A history of the province's role in the first nuclear arms race between the Soviet Union and the United States was provided, and details of provincial public inquiries conducted to legitimize the expansion of uranium mining were revealed. Issues related to the exploitation of ancestral lands belonging to Aboriginal peoples were discussed along with the impact of uranium mining on communities in the province. It was concluded that the province is now being targeted as a storage site for nuclear waste. refs.
A critique of the Saskatchewan uranium royalty
International Nuclear Information System (INIS)
Kwon, O.Y.
1982-01-01
The Saskatchewan uranium royalty system has been in operation since 1976. The objectives of the system are: 1) to ensure a minimum return to the province from extraction of uranium; 2) to capture a fair share of the 'excess' profits; 3) to provide the producers with an adequate rate of return on investment; and 4) to leave marginal production decisions unaffected. The last three objectives are intended to capture pure profits or economic rents without distorting uranium developments. Taxation as an instrument for effecting such an objective is referred to as neutral taxation. This paper evaluates the Saskatchewan system first in the light of neutral taxation, and second in light of the objective of ensuring a minimum return to the province
Uranium mining environmental restoration project (PRAMU)
International Nuclear Information System (INIS)
Asenjo, A.
2002-01-01
The National Atomic Energy Commission (CNEA) started its activities 50 years ago and obtained significant results. At the present time, the CNEA is defined as an Institution of research and development in the nuclear field. It is also responsible for the management of radioactive wastes and the dismantling of nuclear and radioactive facilities. Mining and milling activities have been carried out during the past 40 years and at present the CNEA is undertaking the Uranium Mining Environmental Restoration Project (PRAMU). The aim of this project is to restore the environment as much as is possible in all places where uranium mining and milling activities were developed when taking into consideration both economic and technical reality. First, the characteristics of the problems in each site are determined through appropriate studies which identify the existing or potential impacts, the possible pathways of contamination, etc. The sites being studied are: MALARGUE (Mendoza Province), CORDOBA (Cordoba Province), LOS GIGANTES (Cordoba Province), HUEMUL (Mendoza Province), PICHINAN (Chubut Province), TONCO (Salta Province), LA ESTELA (San Luis Province), LOS COLORADOS (La Rioja Province). PRAMU seeks to improve the current conditions of the tailings deposits and mines and to ensure the long term protection of people and the environment. The CNEA is required to comply with all legislation that is in force and is under the control of various national, provincial and local State institutions. The main objectives of the project for the various sites are: (a) Malargue site: to implement the actions necessary for environmental restoration and management of the tailings derived from the uranium ores processed in the industrial plant; (b) Cordoba and Los Gigantes sites: to design, engineer and execute the activities required for closure of the sites; (c) Other sites (Huemul, Pichinan, Tonco, La Estela, Los Colorados): to develop an environmental evaluation and, on the basis of
A new edition global map - Uranium deposits of the world
International Nuclear Information System (INIS)
Fairclough, M.
2014-01-01
In 1995 The International Atomic Energy Agency published a hard copy map entitled “World Distribution of Uranium Deposits” at a scale of 1:30 000 000. The map displayed data from agency information that was to become UDEPO database of uranium deposits, overlaid on a generalised geological map supplied by the Geological Survey of Canada. At that time, the database contained 582 deposits with a cut-off of 500 t U at an average grade of 0.03% U, and was generated over a period of half a decade by small group external experts. The experts developed a revised deposit classification scheme displayed on the map and in the accompanying guidebook in 1996. A revised and expanded UDEPO database was made widely available on the internet from 2004, and contained additional deposit information and a constantly increasing number of deposits (874 by the end of 2008 coinciding with a new UDEPO guidebook in 2009). Enhanced efforts by the IAEA and consultants of the UDEPO Working Group have now generated a database that has 1526 deposits with a more detailed classification subdivision utilised in a forthcoming IAEA UDEPO publication. The establishment of this classification scheme and the completion of a major phase of updating UDEPO has created an opportunity for creating a completely new edition of the Uranium Deposits Of The World Map using modern GIS techniques. Cartographic tools within GIS software have become very sophisticated, allowing better display of variably dense data through real-time manipulation of layers and symbology with the GIS dataset. Moreover, some of the results of this functionality can then be transferred to the data display aspects the online version of UDEPO as well as distributed as scale-independent digital version of the map. In parallel, a planned IAEA publication regarding global uranium provinces allows a more rigorous clustering of deposits for the purposes of showing particular metallogenic aspects in more detail. This also has an important
Uranium occurrences and exploration experience in India
International Nuclear Information System (INIS)
Chaki, A.
2010-01-01
As per the Indian Government laws, minerals containing uranium are classified as strategic and uranium exploration and mining is an exclusive subject of the Central Government. Exploration for atomic minerals began in India in the year 1949 and, over a period of sixty years, India has created a large pool of uranium scientists and, at present, more than 500 scientists are employed by the Government of India for exploration of atomic minerals in India. In line with other countries, India's efforts in the 1960s, 1970s and 1980s were focused in the exploration for vein-type mineralization and succeeded in the discovery in three provinces, viz. Singhbhum Shear Zone (SSZ), Jharkhand; Umra, Rajasthan and Lesser Himalayas of Uttarakhand and Himachal Pradesh. Of these, the SSZ has emerged as a major uranium province with 17 low-grade, low- to medium-tonnage deposits. Presently, the only uranium producing mines are situated in this province. Simultaneously, many uranium occurrences and deposits of QPC, vein and metasomatite types, essentially of low grade, low tonnage, were located all over the country. In the early eighties, the Cretaceous Mahadek basin in the northeastern state of Meghalaya was recognized as a potential province for sandstone-type uranium mineralization and, within a span of fifteen years, five low- to medium-grade, low-tonnage deposits were established. The 180-km long belt of Cretaceous fluviatile felspathic sandstones along the southern fringe of Shillong plateau below a moderate cover of tertiary sediments holds potential for more resources. Ground and airborne geophysical techniques are being looked at to provide vital clues on depositional controls for future sub-surface exploration. In the mean time, a major uranium province in the southern part of Proterozoic Cuddapah basin was discovered, where uranium mineralization is hosted in dolomitic limestone. The mineralization is stratabound and occurs intermittently over a strike length of nearly 160 km
Uranium mining operations in Spain
International Nuclear Information System (INIS)
Rios, J.-M.; Arnaiz, J.; Criado, M.; Lopez, A.
1995-01-01
The Empresa Nacional del Uranio, SA (ENUSA) was founded in 1972 to undertake and develop the industrial and procurement activities of the nuclear fuel cycle in Spain. Within the organisation of ENUSA, the Uranium Division is directly responsible for the uranium mining and production operations that have been carried out since 1973 in the area of Ciudad Rodrigo in the province of Salamanca. These activities are based on open pit mining, heap leaching and a hydrometallurgical plant (Elefante) for extracting uranium concentrates from the ore. This plant was shut down in 1993 and a new plant was started up on the same site (Quercus) with a dynamic leaching process. The nominal capacity of the new plant is 950 t U 3 O 8 per year. Because of the historically low uranium prices which have recently prevailed, the plant is currently running at a strategic production rate of 300 t U 3 O 8 per year. From 1981 to 1990, in the area of La Haba (Badajoz province), ENUSA also operated a uranium production site, based on open pit mining, and an experimental extraction plant (Lobo-G). ENUSA is currently decommissioning these installations. This paper describes innovations and improvements that ENUSA has recently introduced in the field of uranium concentrates production with a view to cutting production costs, and to improving the decommissioning and site restoration processes in those sites where production is being shut down or resources have been worked out. (author)
Development of simulator for the uranium enrichment plant using a real-time expert system
International Nuclear Information System (INIS)
Kodama, Shinichi; Kondo, Kazuhiro.
1996-01-01
The uranium enrichment plant simulator of the new material centrifuge cascade for intelligent process monitoring and alarm generation has been developed by applying an artificial intelligence technology. The real time expert shell, G2 has been used for the system development. The UF6 supply system and cascade equipment was modeled using G2. For a detailed calculation of the cascade, the cascade static characteristic FORTRAN program has been used. These calculation results have been used for the diagnosis of a suspicious behavior in measurement data. Especially, when the deviation of the product uranium concentration was detected, the cause of the deviation was inferred from the knowledge base. (author)
International Nuclear Information System (INIS)
Sun Yue; Li Juchu; Ding Jun; Yao Yifeng; Xiang Jie; Wang Zhanyong
2014-01-01
Moyite body of middle and late period is filled with normal lamprophyre and lamprophyre of uranium mineralization along cracks of Yan Mountain at the west of Mianning country, Sichuan Province. There are significant differences between the two types of lamprophyre, such as petrological characteristics, output location and scale, radioactive anomalies and geochemical characteristics. The main types of rocks are camptonite, mica-plagioclase lamprophyre and minette. Mineralized lamprophyre belongs to potassic-ultrapotassic lamprophyre according to macro-element analysis, while normal lamprophyre belongs to lamprophyre of calc-alkaline type. The transition elements allocation model are both mantle 'W' type with LILE (K, Rb, Ba) and HFSE (Nb, Ta, Zr, Hf). The rare earth elements allocation model of normal lamprophyre is Rightist LREE with δEu value of 0.73∼0.87. The rare earth elements allocation model of mineralized lamprophyre is 'M' type with δEu value of 0.28∼0.48. It indicates that lamprophyre is the result of partial melting of enriched mantle, and mineralized lamprophyre can be changed obviously by fluid flow. In the area, the type of uranium mineralization is that of vein rock, which is strictly controlled by mineralization lamprophyre, that is a new type of uranium mineralization in China. (authors)
Uranium exploration in Australia
International Nuclear Information System (INIS)
Battey, G.C.; Hawkins, B.W.
1977-01-01
As a result of exploration which recommenced in 1966 Australia's uranium reserves increased from 6,200 tonnes in 1967 to 227,000 tonnes uranium by June 1976. Most discoveries in the early 1950's were made by prospectors. The increase in reserves during the past decade is the result of exploration by companies utilising improved technology in areas selected as geologically favourable. These reserves were established at relatively low cost. In the Alligator Rivers Uranium Province the ''vein'' type deposits at Jabiluka, Ranger, Koongarra and Nabarlek contain 17% of the world's reserves. Most of these discoveries resulted from the investigation of airborne radiometric anomalies but cover over the prospective host rocks will necessitate the future use of costlier and more indirect exploration techniques. There was exploration for sandstone type uranium deposits in most of Australia's sedimentary basins. The greatest success was achieved in the Lake Frome Basin in South Australia. Other deposits were found in the Ngalia and Amadeus Basins in Central Australia and in the Westmoreland area, N.W. Queensland. A major uranium deposit was found in an unusual environment at Yeelirrie, Western Australia where carnotite occurs in a caliche and clay host which fills a shallow, ancient drainage channel. Although caliche occurrences are relatively widespread on the Precambrian shield no other economic deposit has been found. Recent discoveries in the Georgetown area of Queensland indicate the presence of another uranium province but it is too early to assess its potential. The ore occurs in clastic sediments at the base of a volcanic sequence overlying a Precambrian basement. Several companies which have established large uranium reserves have a number of additional attractive prospects. Exploration activity in Australia in 1975 was at a lower level than in previous years, but the potential for discovering further deposits is considered to be high
Uranium deposit research, 1983
International Nuclear Information System (INIS)
Ruzicka, V.; LeCheminant, G.M.
1984-01-01
Research on uranium deposits in Canada, conducted as a prerequisite for assessment of the Estimated Additional Resources of uranium, revealed that (a) the uranium-gold association in rudites of the Huronian Supergroup preferably occurs in the carbon layers; (b) chloritized ore at the Panel mine, Elliot Lake, Ontario, occurs locally in tectonically disturbed areas in the vicinity of diabase dykes; (c) mineralization in the Black Sturgeon Lake area, Ontario, formed from solutions in structural and lithological traps; (d) the Cigar Lake deposit, Saskatchewan, has two phases of mineralization: monomineralic and polymetallic; (e) mineralization of the JEB (Canoxy Ltd.) deposit is similar to that at McClean Lake; (f) the uranium-carbon assemblage was identified in the Claude deposit, Carswell Structure; and (g) the Otish Mountains area, Quebec, should be considered as a significant uranium-polymetallic metallogenic province
Regional metallogenic essential factor of granite-type uranium deposits in Guangdong province
International Nuclear Information System (INIS)
Pan Yongzheng
1987-12-01
The uranium origin, activation region, red basin, and fault depressed zone constitute the regional metallogenic essential factor of the four united like one granite-type uranium deposits in the post-Caledonian rise area in China. In the development of sub-geosyncline in the Caledonian, the clastic formation with widely deposited carbon, silicon, mud rich bearing organic matter, which drow a great amount of uranium formed the uranium-bearing system in the Sinian-Cambrian period. The magmagranite activation in a large scale in the Indosinian-Yenshanian period caused the continental crust to be suffered strong reformation and the uranium-bearing basement system to be eroded and remelted, and formed the rich uranium granite body. The multiple structure-magmatic movement further made the uranium in the rock body suffered the endogenic, structure, supergene active reformation, and produced mobile uranium concentrated area. Under the dry and hot paleoclimate condition in the Cretaceous-Tertiary period, strong weathering and hot water leaching forced uranium to be concentrated into the 'rock origin activation' type uranium deposits in the fault depressed zone
International Nuclear Information System (INIS)
Anon.
1981-01-01
In 1980 the government of British Columbia called off the Bates Commission inquiry into uranium mining and declared a seven-year moratorium on uranium exploration in the province. Since then the commission has issued its final report, which included the recommendation that exploration could proceed safely. The provincial government, however, has refused to lift the ban. In its other recommendations the Bates Commission stated that future energy needs may require the development of all known uranium resources; that advances in miner protection and tailings disposal could soon make uranium mining acceptably safe; and that uranium mining is morally and ethically acceptable. Specific recommendations on research needs that should be met before uranium mining is allowed in British Columbia were made. (LL)
International Nuclear Information System (INIS)
Tjokrokardono, Soeprapto
2002-01-01
Uranium exploration activities done by CEA-BATAN had discovered uranium occurrences as the radiometric and uranium content anomalies at metamorphic and granite rocks of Schwaner Mountains, Kalimantan. A part of the occurrences on metamorphic rocks at Kalan basin has been evaluated and be developed onto follow-up step of prospecting by construction of some drilling holes and an exploration adit. In order to increase the national uranium resources, it is necessarily to extent the exploration activity to out side or nearby of Kalan basin. The goal of this assessment is to understand the uranium accumulation mechanism at Pinoh metamorphic rocks of Kalan Kalimantan and to delineate areas that uranium may exist. The assessment was based on the aspect of geology, anomaly of radioactivity and uranium contents, tectonics and alterations. Pinoh metamorphic rocks which is influenced by Sukadana granite intrusion are the high potential rocks for the uranium accumulation, because the intrusion contains a relatively high of U, Th, Cu, Zn, Nb, Mn, and W. The potential rock distributions are in between G. Ransa granite intrusion at the east and Kotabaru granite intrusions at the west. The mineralizations are categorized as vein type deposits of granitic association
Uranium production, exploration and mine development in Canada
International Nuclear Information System (INIS)
Vance, R. E
2006-01-01
Full text: Full text: Canada has been the world leader in uranium production since the early 1990's and production in 2005 was 11,629 te U. The Elliott Lake region of Ontario was once the centre of production, but after the last facilities closed in 1996, all production now comes from the Athabasca Basin in northern Saskatchewan. Average grades of the world's two largest high grade deposits at McArthur River and Cigar Lake are 10 to 100 times the grade of deposits mined elsewhere. McArthur River has been in production since late 1999 and first production from Cigar Lake is expected in 2007. If all expansion and probable mine openings come to fruition, annual Canadian production could amount to 16,000 te U by 2011. All currently operating uranium mines have been the subject of a comprehensive environmental assessment and review process. Uranium mining brings significant benefits to local area residents in northern Saskatchewan. Residents of northern Saskatchewan are active participants in Environmental Quality Committees. Recent survey results show the majority of Saskatchewan residents support the continuation of uranium mining in the province. The closed uranium mines in Canada have been successfully decommissioned and rehabilitated in particular in the Elliott Lake region of Ontario. The principle exploration target in Canada remains the Athabasca Basin, but activity has also been reported in several of the other territories and provinces. Natural Resources Canada estimates that some $CAN81M was spent on exploration in Canada in 2005. Under the Canadian Constitution, natural resources are owned by the provinces or by the federal government if they are on federal lands north of 60 0 C latitude. The provinces have jurisdiction over exploration activities within their borders and for most commodities have jurisdiction over mine development and production, operations, health and safety and environmental matters. Once a company starts to develop a deposit into a mine
International Nuclear Information System (INIS)
Solis, R.J.; Navarra, P.R.; Benitez, A.F.; Gallucci, A.R.
1993-01-01
The Cerro Solo ore deposit was selected by the CNEA to invest in an assessment project because of their promising grade and amount of known and potential resources, significant to Argentina's uranium requirements. The deposit, which is located in the central region of the Chubut Province, belongs to the sandstone type and is hosted by the cretaceous Chubut Group. Technical studies carried out forecast an important growth of nuclear capacity to meet Argentina's energy requirements in the first two decades of of the the next century. To be in position to confront the challenge presented by increasing uranium resources to fuel the nuclear powers plants it is very important, as a first step, to improve the geological knowledge of uranium favorability in the country. The preliminary results of the Cerro Solo project indicate that the eastern slope of the Pichinan hills is a promising area for development of uranium resources, increasing the favorability of the San Jorge Basin in order to allow contributing to meet future uranium requirements. The Cerro Solo Project was planned in a sequential manner, as a multidisciplinary effort which includes studies on: geologic setting of mineralization, resource estimates, costs of mining and milling methods, economic analysis and environmental impact research. Among the mining methods, studies include the alternative of the in-situ leaching technology, which is becoming a low producing cost interesting possibility. (Author)
Surficial uranium deposits in Somalia
International Nuclear Information System (INIS)
Briot, P.
1984-01-01
Surficial uranium deposits in Somalia are of the valley-fill calcrete type and occur in the arid Mudugh Province of the Dusa Mareb-El Bur region. They are located in a belt about 240 km in length which is orientated parallel to the north-south regional tectonic framework. The uranium resources of the region amount to about 5,000 t U 3 O 8 at an average grade of 0.1% U 3 O 8 . Basement rocks constitute a 7,000 m thick succession of Jurassic to Quaternary sediments of the Somalian Basin. Uranium mineralization in the form of carnotite occurs in the uppermost Mercia Series. The origin of the uranium and vanadium is unclear due to a shortage of the favourable source rocks. (author)
International Nuclear Information System (INIS)
Santos, L.C.S. dos.
1985-01-01
Estimatives of uranium reserves carried out in Figueira, Itataia, Lagoa Real and Espinharas, in Brazil are presented. The samples testing allowed to know geological structures, and the characteristics of uranium mineralization. (M.C.F.) [pt
Energy Technology Data Exchange (ETDEWEB)
Wang, Jin; Song, Gang; Chen, Yongheng; Zhu, Li [Key Laboratory of Waters Safety and Protection in the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou (China); Liu, Juan [Key Laboratory of Waters Safety and Protection in the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou (China); Department of Geosciences, National Taiwan University, Taipei (China); Li, Hongchun [Department of Geosciences, National Taiwan University, Taipei (China); Xiao, Tangfu [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang (China); Qi, Jianying [South China Institute of Environmental Science, Ministry of Environmental Protection, Guangzhou (China)
2012-12-15
The northern region of Guangdong Province, China, has suffered from the extensive mining/milling of uranium for several decades. In this study, surface waters in the region were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES) for the concentrations of uranium (U), thorium (Th), and non-radioactive metals (Fe, Mn, Mg, Li, Co, Cu, Ni, and Zn). Results showed highly elevated concentrations of the studied radionuclides and metals in the discharged effluents and the tailing seepage of the U mining/milling sites. Radionuclide and heavy metal concentrations were also observed to be overall enhanced in the recipient stream that collected the discharged effluents from the industrial site, compared to the control streams, and rivers with no impacts from the U mining/milling sites. They displayed significant spatial variations and a general decrease downstream away from upper point-source discharges of the industrial site. In addition, obvious positive correlations were found between U and Th, Fe, Zn, Li, and Co (R{sup 2} > 0.93, n = 28) in the studied water samples, which suggest for an identical source and transport pathway of these elements. In combination with present surface water chemistry and chemical compositions of uraniferous minerals, the elevation of the analyzed elements in the recipient stream most likely arose from the liquid effluents, processing water, and acid drainage from the U mining/milling facilities. The dispersion of radionuclides and hazardous metals is actually limited to a small area at present, but some potential risk should not be negligible for local ecosystem. The results indicate that environmental remediation work is required to implement and future cleaner production technology should be oriented to avoid wide dispersion of radioactivity and non-radioactive hazards in U mining/milling sites. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
International Nuclear Information System (INIS)
Tsalyuk, Yu.; Gurevich, D.
2000-01-01
Over 25 % of the world's uranium reserves are concentrated in Kazakhstan. So, the world's largest Shu-Sarysu uranium province is situated on southern Kazakhstan, with resources exceeding 1 billion tonnes of uranium. No less, than 3 unique deposits with resources exceeding 100,000 tonnes are situated here. From the economic point of view the most important thing is that these deposits are suitable for in-situ leaching, which is the cheapest, environmentally friendly and most efficient method available for uranium extracting. In 1997 the Kazatomprom National Joint-Stock Company united all Kazakhstan's uranium enterprises (3 mine and concentrating plants, Volkovgeologiya Joint-Stock Company and the Ulbinskij Metallurgical plant). In 1998 uranium production came to 1,500 tonnes (860 kg in 1997). In 1999 investment to the industry were about $ 30 million. Plans for development of Kazakhstan's uranium industry provide a significant role for foreign partners. At present, 2 large companies (Comeco (Canada), Cogema (France) working in Kazakhstan. Kazakatomprom continues to attract foreign investors. The company's administration announced that in that in next year they have plan to make a radical step: to sell 67 % of stocks to strategic investors (at present 100 % of stocks belongs to state). Authors of the article regard, that the Kazakhstan's uranium industry still has significant reserves to develop. Even if the scenario for the uranium industry could be unfavorable, uranium production in Kazakhstan may triple within the next three to four years. The processing of uranium by the Ulbinskij Metallurgical Plant and the production of some by-products, such as rhenium, vanadium and rare-earth elements, may provide more profits. Obviously, the sale of uranium (as well as of any other reserves) cannot make Kazakhstan a prosperous country. However, country's uranium industry has a god chance to become one of the most important and advanced sectors of national economy
NURE uranium deposit model studies
International Nuclear Information System (INIS)
Crew, M.E.
1981-01-01
The National Uranium Resource Evaluation (NURE) Program has sponsored uranium deposit model studies by Bendix Field Engineering Corporation (Bendix), the US Geological Survey (USGS), and numerous subcontractors. This paper deals only with models from the following six reports prepared by Samuel S. Adams and Associates: GJBX-1(81) - Geology and Recognition Criteria for Roll-Type Uranium Deposits in Continental Sandstones; GJBX-2(81) - Geology and Recognition Criteria for Uraniferous Humate Deposits, Grants Uranium Region, New Mexico; GJBX-3(81) - Geology and Recognition Criteria for Uranium Deposits of the Quartz-Pebble Conglomerate Type; GJBX-4(81) - Geology and Recognition Criteria for Sandstone Uranium Deposits in Mixed Fluvial-Shallow Marine Sedimentary Sequences, South Texas; GJBX-5(81) - Geology and Recognition Criteria for Veinlike Uranium Deposits of the Lower to Middle Proterozoic Unconformity and Strata-Related Types; GJBX-6(81) - Geology and Recognition Criteria for Sandstone Uranium Deposits of the Salt Wash Type, Colorado Plateau Province. A unique feature of these models is the development of recognition criteria in a systematic fashion, with a method for quantifying the various items. The recognition-criteria networks are used in this paper to illustrate the various types of deposits
International Nuclear Information System (INIS)
Angelelli, Victorio.
1984-01-01
The main uranium deposits and occurrences in the Argentine Republic are described, considering, in principle, their geologic setting, the kind of 'model' of the mineralization and its possible origin, and describing the ore species present in each case. The main uraniferous accumulations of the country include the models of 'sandstong type', veintype and impregnation type. There are also other kinds of accumulations, as in calcrete, etc. The main uranium production has been registered in the provinces of Mendoza, Salta, La Rioja, Chubut, Cordoba and San Luis. In each case, the minerals present are mentioned, having been recognized 37 different species all over the country (M.E.L.) [es
Radiation monitoring of soil cover of natural uranium in the Issyk-Kul province
International Nuclear Information System (INIS)
Djenbaev, B.M.; Toktoeva, T.E.; Kaldibaev, B.K.; Zholbolduev, B.T.
2015-01-01
This article presents the current state in the radioecological soil Issyk-Kul province of natural uranium. Found that the background radiation - exposure dose and artificial radionuclides in the soil of the coastal zone of the lake as a whole at the level of the background and the acceptance of lower standards except for natural technogenic and some natural areas. Radioecological this province is mild natural and industrial uranium province.We have previously established 10 experimental plots around Issyk-Kul and the measurement showed that the power of natural background radiation in the gamma radiation of the coastal lake zone is an average of 17 to 25 mR/h in some areas up to 40 mR/h. As the distance from the lake to the side slopes of its level in some places rises to 40 mR/h, especially in some mountainous areas, canyons, which are based on the rocks, granites and their fragments are small, red sand, with a slightly increased radioactivity. For small areas with high natural background radiation can be attributed to the beaches of the coastal zone v. Jenish, v. Ak-Terek, located on the southern shore of Issyk-Kul Lake. The radioactivity of 30 - 60 mR/h, and in areas with a high content of iron in the sand inclusions level exposure dose increases up to 400 mR/h. Small areas of the coastal zone of Issyk-Kul Lake, mostly mud deposits with characteristic brilliance giving high radiation background. These areas include: the beach v.Tosor - 40-50 mR/h, 10 km west of the coast v.Kaji-Sai - 32-40 mR/h, the shore around with. Toru-Aigyr - 30 mR/h, the coast around v.Tamchi - 40-50 mR/h. In general, cities in the Issyk-Kul basin Kara-Kol, Cholpon-Ata and Balykchy radiation situation quite well, the average exposure dose of gamma radiation does not exceed 20 - 22 mR/h, but in some places the use of crushed granite, as filler and construction material, the level of background radiation increases to 40-50 mR/h This indicates that these natural resources, without first
International Nuclear Information System (INIS)
Aniel, Mlle B.; Hetland, Donald L.; Glassom, Pierre J.
1983-07-01
The results of the study carried out during the IUREP Orientation Phase in Morocco permit to think that the possible reserves of uranium in this country range between 33,500 t and 89,500 t U 3 O 8 for what concerns the known traces and the already prospected zones in the Northern provinces. If we consider the favourability criteria of certain geological contexts that have not been researched yet in the same provinces and the speculative potential of the Southern provinces that have not been prospected at all, we can reasonably estimate reserves to double. In this case, the potential in uranium for the whole Morocco could range between 70,000 and 180,000 tons. The uranium phosphate constitutes by far the most important reserves of Morocco and the Moroccan government has decided to recuperate this uranium as sub-product from phosphoric acid. The consultants of the IUREP mission have estimated that the 'geological reserves' were ranging at about 12,3 million tons of U 3 O 8 and that the recoverable reserves could be between 7 and 10 million tons of U 3 O 8
Fluid inclusion study of the Cachoeira uranium deposit, Caetite, state of Bahia, Brazil
International Nuclear Information System (INIS)
Alves, J.V.; Fuzikawa, K.
1984-01-01
The Cachoeira uranium deposit is presently the richest deposit among those in the Lagoa Real Uranium Province. The mineralization is associated to the albitites formed during the onset of strong sodium metasomatism on the granite-gnaissic rocks of the area. Fluid inclusion study of several uraniferous albitites indicated the presence of strong brines (approx. 20 weight percent NaCl equivalent) and the dominance of hydrocarbons over CO 2 in the gas phase. In country rocks, which host the albitites, as well as in unmineralized albities the salinity of aqueous solution is variable and light hydrocarbons are the predominant gas phase. These data were obtained by microthermometry and crushing tests from a larger set of samples than that used in previous studies. However, the results do not differ significantly from the data of these earlier works and reinforce the hypothesis of the importance of CH 4 in Uo 2 precipitation. (Author) [pt
Environmental control and radioprotection in Itataia and Lagoa Real uranium mines
International Nuclear Information System (INIS)
Cenachi, N.C.
1988-01-01
Monitoring Programs in Itataia and Lagoa Real uranium mines were initiated in 1982. In the actual pre-operational phase of this Programs, are being collected samples of air, surface and underground waters, stream sediments, soil, field products, and milk. Environmental contamination of air is controlled by thermoluminescent dosimeters, distributed around the mines. Instantaneous radiation measures in this stations are made with scintillometer calibrated in Radioprotection Laboratory Department-CDTN. Photographic dosimeters are used for monitoring external radiation exposures in workers. Radiation levels evaluation, air and surface contamination measures, were effectuated in installations, trenches, and research galleries. Another factors which are now being studied: climate, meteorology, and hidrology. (author) [pt
The Streltsovskoye uranium district
International Nuclear Information System (INIS)
Ischukova, L.P.
1997-01-01
This paper describes the geology of the Streltsovskoye uranium district located in south-eastern Zabaikalie region, Chita Province, Siberia, Russia. This district hosts Russia's only currently active uranium production centre. The uranium ore was discovered from 1963 to 1967 by drilling below fluorite veins which had minor associated uranium mineralization and radioactive anomalies. The uranium occurs as large scale vein stockwork deposits of hydrothermal origin within a volcano-tectonic caldera formed by continental volcanism of Late Mesozoic age. Rocks occurring in the caldera include basalt and trachydacite, overlain by rhyolite, and with associated interbedded sediments. The ore bodies occur in steeply dipping faults, with the greatest concentrations located where faults along the margins of the caldera intersect steeply dipping, cross cutting, northeasterly and northwesterly striking faults. The Streltsovskoye caldera extends over an area of 150 km 2 and is underlain by a large batholith. The 19 identified uranium deposits occurred in structural features that cut through the caldera sequence and extend into the basement rocks. The caldera has a maximum thickness of 1400 metres. Details of several deposits are given, including descriptions of mineralization and associated alteration. (author). 10 figs
International Nuclear Information System (INIS)
Batbold, T.
2001-01-01
Uranium exploration in Mongolia covered a period of over 5 decades. The main results of these activities were the discoveries of 6 uranium deposits and about 100 occurrences as well as numerous favourable indications. Sizable resources are found mainly in deposits of the sandstone, volcanic and alkaline intrusive types. Of these, the first two are considered to be of economic importance. Uranium production in Mongolia started in 1989 with the exploitation of volcanic type uranium deposits of the Mongol-Priargun metallogenic province, known as the Dornot Mine. Due to political and economic changes in the country and neighbouring areas of the Russian Federation, this uranium production was terminated in 1995. A new plan to restart production at the Mardai-gol deposits as a joint venture between Mongolia, the Russian Federation and a US company is being considered. (author)
International Nuclear Information System (INIS)
1985-01-01
A report has recently been published on the findings of the mission to Morocco under the International Uranium Resources Evaluation Project (IUREP) Orientation Phase. The IUREP Orientation Phase Mission estimates that the speculative resources of Morocco range from 70 000 to 180 000 tonnes of uranium, half of which could be expected to occur in the Northern Provinces, which are relatively well explored, and the other half in the little explored Southern Provinces. In the north, speculative resources are fairly evenly distributed among the various types of deposit, in particular vein deposits (intragranitic and contact) linked with Hercynian and Precambrian blocks, the sandstone type deposits linked with Mesozoic strata and the volcanogenic deposits, especially of Precambrian age. The potential for large high-grade deposits, especially for those linked with unconformities and linear albitites, has been little investigated in Morocco and is chiefly thought to lie in the Precambrian in the Anti-Atlas and Southern Provinces. Here, the presence of acid volcanic rock reinforces the uranium potential, and there is also some potential for calcrete-related deposits. Phosphate-related uranium, to be recovered shortly, constitutes by far the largest reserves in Morocco, estimated at about 7 million tonnes of recoverable uranium. Recommendations have been made for further study of known occurrences and identification of new ones, such as unconformity and albitite-related deposits. (author) [fr
International Nuclear Information System (INIS)
1985-01-01
A report has recently been published on the findings of the mission to Morocco under the International Uranium Resources Evaluation Project (IUREP) Orientation Phase. The IUREP Orientation Phase Mission estimates that the speculative resources of Morocco range from 70 000 to 180 000 tonnes of uranium, half of which could be expected to occur in the Northern Provinces, which are relatively well explored, and the other half in the little explored Southern Provinces. In the north, speculative resources are fairly evenly distributed among the various types of deposit, in particular vein deposits (intragranitic and contact) linked with Hercynian and Precambrian blocks, the sandstone type deposits linked with Mesozoic strata and the volcanogenic deposits, especially of Precambrian age. The potential for large high-grade deposits, especially for those linked with unconformities and linear albitites, has been little investigated in Morocco and is chiefly thought to lie in the Precambrian in the Anti-Atlas and Southern Provinces. Here, the presence of acid volcanic rock reinforces the uranium potential, and there is also some potential for calcrete-related deposits. Phosphate-related uranium, to be recovered shortly, constitutes by far the largest reserves in Morocco, estimated at about 7 million tonnes of recoverable uranium. Recommendations have been made for further study of known occurrences and identification of new ones, such as unconformity and albitite-related deposits. (author)
International Nuclear Information System (INIS)
Zhou Yulong; Liu Yunlang; Gao Yan
2013-01-01
According to the basic conditions of 'source, guide, transportation, storage' for uranium mineralization in strata and different types of geological structure, departure from the condition, the coupling effect of stratigraphy, lithology and structure are studied in the process of uranium mineralization in northern Xiangshan volcanic basin. Studies show that the northern ore field are of good metallogenic geological conditions and the uranium rich ancient land mass and uranium rich magma generated by the melting of deep metamorphic rocks. The main geologic events are volcanic eruptions, accompanied by repeated subvolcanic magma intrusion and strong faults and nappe tectonics which result in volcanic collapse and volcanic ring structures. These ore-forming geological condition control the structural frame for the formation of main uranium deposit type-subvolcanic rocks in northern Xiangshan ore field. (authors)
A short history of nuclear activities in Mendoza province
International Nuclear Information System (INIS)
Lardone, Leo E.
2005-01-01
Uranium was found in Mendoza in 1946 in 'Soberania' and 'Independencia' mines. After its creation in 1950 CNEA, together with Cuyo National University (UNC), developed the mining industry starting with the 'Papagayos' mine. It can be considered the beginning of the systematic exploitation of uranium in the country. In course of time the province of Mendoza passed to get one of the most uraniferous reserve of Argentina and it has accumulated the major production till now. However, in the last years there has been opposition to resume the production in the Sierra Pintada Uranium Manufacturing Complex. There was also a powerful land continuous progress in the field of no energetic applications of nuclear techniques in the province. The most outstanding example is the 'School of Nuclear Medicine Foundation', with installations in Mendoza city and in San Rafael. Besides, there is a research and development group in Cuyo National University devoted to the Nuclear Safety. Finally, we can not fail to mention the Auger Pierre Project, which is building in Malargue an observatory for the study of the cosmic rays. (author) [es
Sustainability of new uranium mining projects in Argentina
International Nuclear Information System (INIS)
Navarra, P.R.
2002-01-01
The regulatory framework issued in the 1994-1995 period, connected mining activities in Argentina with international good environmental practices. Agreements between National Government and Provinces allow the application of the regulations, while Act No 24.585, the milestone about the matter, establishes the steps for the approval of the Report of Environmental Impact, on successive stages of the project. Specifically for uranium mining and milling, the assessment of the radiological protection aspects of the planned activities is assigned to the Nuclear Regulatory Authority. The National Atomic Energy Commission is at present carrying out two uranium mining projects, that involve the Sierra Pintada and Cerro Solo deposits. The goal of them is restart uranium production in the country in the medium term, by lowing the gap between indigenous and market uranium prices. The first one consists in updating the feasibility study of the, at present inactive, Sierra Pintada Production Center (Mendoza Province). Studies for improving the mining and treatment methods are performed in the project, co-ordinately with the investigation and forecast of mining waste and processing tailings management. Besides, the procedures will be determined taking into account the methodology to be applied when getting the closure stage, about the existing waste and tailings. Development of the Sierra de Pichinan District, Chubut Province (U-Mo), is the objective of the second project. It is remarkable that about Cerro Solo, the main ore deposit belonging to this area, at the prefeasibility stage, CNEA is currently encouraging private investment through a bidding process. Environmental studies are an important aspect of the activities carried out and planned in the area. As a conclusion, with regard uranium mining and milling activities in Argentina, the regulations and environmental technical-scientific knowledge are becoming friendly with the sustainable practice. (author)
International Nuclear Information System (INIS)
Oliveira, Lucilia Aparecida Ramos de
2010-01-01
Brazil has now the seventh largest uranium reserve in the world. The Lagoa Real Uranium Province (PULR) is located in central-south region of Bahia State. Along a helical structure, north-south oriented, with approximately 33 km long, there are 34 known uranium mineralized areas. In its central-south portion is located anomaly 03 (AN03), named Lagoa da Rabicha, discovered and mapped by NUCLEBRAS (Brazilian Nuclear Enterprises), in the 80s. The Cachoeira Mine (AN13), located in northern PULR, is currently the only uranium mine in production in Brazil and even in South America. Nowadays it is observed a growth in energy demand in Brazil and also worldwide and studies and research applied to the petrogenetic uranium deposits are relevant both to be able to increase their potential for exploration and to assist in the possible future occurrences discovery. In recent years, fluid inclusions analysis (FI) have been widely used to study the genesis of uranium deposits in PULR and even thought there are still doubts about the uranium mineralization metallogenesis at Lagoa Real. Therefore, this work aimed to study the minerals and fluids associated with Lagoa da Rabicha albitites uraniferous and gneissic host rocks. In this way it was prepared an overview of the fluids found in this sector, establishing a comparison with several authors' studies in this and others Lagoa Real anomalies, trying to show the solutions evolution, at the same time that happened the uraninite precipitation. Petrography, electronic microprobe, laser ablation (LA-ICP-MS) and fluid inclusion studies were the applied methodologies. The fluids inclusions assemblages present in pyroxene, garnet and plagioclase, the main mineralogical constituents, were studied. The older fluid was found in aegirine-augite pyroxene and had aquo-saline composition (without carbonic phases) with Ca, Fe and Mg, 9-13 wt% NaCl salinities and homogenization temperatures between 220 and 290 deg C. Concomitantly, occurred a
Uranium mineralization in the Rum Jungle-Alligator Rivers Province, Northern Territory, Australia
International Nuclear Information System (INIS)
Dodson, R.G.; Needham, R.S.; Wilkes, P.G.; Page, R.W.; Smart, P.G.; Watchman, A.L.
1974-01-01
Renewed interest in uranium exploration in northern Australia in the late 1960s led to the discovery of one of the most important uranium fields in the world. To obtain an understanding of the geological setting of the uranium deposits, and to provide guidelines for future exploration, the Bureau of Mineral Resources (BMR) undertook an investigation which included semi-detailed mapping, aided by geophysical surveys, isotopic dating, and stratigraphic drilling. From the results so far obtained and from the important data made available by mining companies engaged in exploration in the region, a pattern of uranium mineralization can be recognized, particularly in relation to the Lower Proterozoic sedimentation of the region. (author)
Uranium in tertiary stream channels, Lake Frome area, South Australia
International Nuclear Information System (INIS)
Brunt, D.A.
1978-01-01
Uranium exploration over a wide area of the Southern Frome Embayment, South Australia, has defined a number of Lower Tertiary fluvial palacochannels incised in older rocks. The buried channels contain similar stratigraphic sequences of interbedded sand, silt, and clay, probably derived from the adjacent uranium-rich Olary Province. Uranium mineralization is pervasive within two major palacochannels, and four small uranium deposits have been found in the basal sands of these channel sequences, at the margins of extensive tongues of limonitic sand. A genetic model is proposed suggesting formation by a uraniferous geochemical cell which migrated down the stream gradient and concentrated uranium on its lateral margins adjacent to the channel bank
The Brazil-Angola alkaline - carbonatite province and its main economic aspects
International Nuclear Information System (INIS)
Loureiro, F.E.V.L.; Di Valderano, M.H.W.
1982-01-01
The principal characteristics of the Brazil-Angola Alkaline Carbonatite Province are defined and described with specific reference to tectonic setting and economic aspects. The economic aspects of the Brazilian uranium deposits are emphasised. The Brazil-Angola Alkaline-Carbonatite Province can be divided into six Brazilian sub-provinces and two Angolan sub-provinces. Correlation between the sub-provinces of Brazil and Angola remains speculative due to the lack of detailed information, especially age determinations on the Angolan rocks. However, an analysis of the tectonic and petrochemical aspects suggests that the two Brazilian sub-provinces situated along the littoral of Rio de Janeiro/ Sao Paulo and around the periphery of the Parana Basin may be more easily comparable to the two Angolan sub-provinces than the remaining four. (Author) [pt
International Nuclear Information System (INIS)
Stein, J.H.; Netto, A.M.; Drummond, D.; Angeiras, A.G.
1980-10-01
A brief description and interpretation of the development of the processes of albitization in Russia, Sweden and Brazil, is presented. Based on the comparison of similar characteristics, interpreted and suggested, in the light of present knowledge, it is proposed to set a place in time and space for the uranium mineralization at Lagoa Real. A zoning of the Sn, Cu, Ba, Pb and Zn with respect to the uranium mineralization is suggested. (Author) [pt
International Nuclear Information System (INIS)
Li Yaosong; Zhu Jiechen; Xia Yuliang
1992-02-01
Zircon characteristic and its relation to uranium metallogenetic process have been studied on the basis of physics properties and chemical compositions. It is indicated that the colour of zircon crystal is related to uranium concentration; on the basis of method of zircon population type of Pupin J.P., the sectional plan of zircon population type has been designed, from which result that zircon population type of uranium-producing rock body is distributed mainly in second section, secondly in fourth section; U in zircon presents synchronous increase trend with Th, Hf and Ta; the uranium concentration in zircon from uranium-producing geologic body increases obviously and its rate of increase is more than that of the uranium concentration in rock; the period, in which uranium concentration in zircon is increased, is often related to better uranium-producing condition in that period of this area. 1785 data of the average uranium concentration in zircon have been counted and clear regularity has been obtained, namely the average uranium concentrations in zircon in rich uranium-producing area, rock, geologic body and metallogenetic zone are all higher than that in poor or no uranium-producing area, rock, geologic body and metallogenetic zone. This shows that the average uranium concentration in zircon within the region in fact reflects the primary uranium-bearing background in region and restricts directly follow-up possibility of uranium mineralization. On the basis of this, the uranium source conditions of known uranium metallogenetic zones and prospective provinces have been discussed, and the average uranium concentrations in zircon from magmatic rocks for 81 districts have been contrasted and graded, and some districts in which exploration will be worth doing further are put forward
Khan, Naeemullah; Tuzen, Mustafa; Kazi, Tasneem Gul
2017-11-01
An innovative, rapid, and simple dual-dispersive liquid-liquid microextraction (DDLL-ME) approach was used to extract uranium from real samples for the first time. The main objective of this study was to disperse extraction solvent by using an air-agitated syringe system to overcome matrix effects and avoid dispersion of hazardous dispersive organic solvents by using heat. The DDLL-ME method consisted of two dispersive liquid-liquid extraction steps with chloroform as the extracting solvent. Uranium formed complexes with 4-(2-thiazolylazo) resorcinol in the aqueous phase and was extracted in extracting solvent (chloroform) after the first dispersive liquid-liquid process. Uranium was then back-extracted in the acidic aqueous phase in a second dispersive liquid-liquid process. Finally, uranium was determined by a spectrophotometric detection technique. The variables that played a key role in the proposed method were studied and optimized. The LOD and sensitivity enhancement factor for uranium were found to be 0.60 µg/L and 45, respectively, under optimized conditions. Calibration graphs were found to be linear in the range of 5.0-600 µg/L. The RSD was 2.5%. Reliability of the proposed method was verified by analyzing certified reference material TM-28.3.
Near real-time inventory and accountability within a uranium enrichment plant
International Nuclear Information System (INIS)
Wheeler, L.E.; Scott, P.H.
1983-01-01
The Oak Ridge Gaseous Diffusion Plant Inventory Control and Accountability System (ORICAS) utilizes state-of-the-art hardware, software, and communication to provide a computerized near real-time inventory of materials within a Uranium Enrichment Plant. Work stations are located in five strategic areas within the plant. Accountability areas include material receipt, enrichment, withdrawal, sampling, intraplant transfer, and shipment. Perpetual current inventory is maintained and is available to authorized users on-line and in printed reports. The system meets DOE material reporting requirements and provides accountability safeguards for early detection of possible loss or diversion. Hardware consists of multiple data input terminals and printers linked to a time-shared computer. Major software includes COBOL and IDMS (an Integrated Data Base Management System)
Geology and uranium occurrences of the Himalaya
International Nuclear Information System (INIS)
Singh, Rajendra
1997-01-01
The Himalayan terrain constitutes one of the important uranium provinces of India. Mineral economics in the conventional sense will always be against any mineral deposit in the Himalaya until a very advanced stage of development in areas of transport and communication is achieved
Uranium occurrences in the pegmatite 'Las Cuevas', province of San Luis, Argentine Republic
International Nuclear Information System (INIS)
Daziano, C.O.; Karlsson, A.C.; Ayala, R.
1993-01-01
Mineral associations found in an uranium deposit of Sierras Pampeanas, San Luis, are considered in these papers. Damourite stands out among the uranium minerals related to uraninite and coffinite. Pyrite, marcasite and other sulphides are found together with apatite and gummite. Autunite is the uranium secondary mineral more abundant. A mineralization with epigenetic contribution by circulating solutions is suggested to the studied area. (Author)
International Nuclear Information System (INIS)
Bertolini, A.; Pretorius, L.; Weideman, M.; Scheepers, T.
1985-09-01
The report is a bibliography of approximately one thousand maps. The maps contain information of ESSO Minerals Company's prospecting activities for mainly uranium in South Africa. ESSO explorated for uranium in the Karoo, Northwestern Cape and the Bushveld. The bibliography contains two indexes. The one is a list of prospects and projects as per geological province and the other is an alphabetic list of projects and prospects. Three geological provinces are distiguished, namely, the Bushveld province, Karoo province and Namaqualand province. The annotations contain information on the location and geographic area of the map, the name of the project or prospect, the title, a statement of resposibility (this includes the compiles i.e. geologists, and/or draftsmen), the statement of scale which is always expressed as a ratio, the date of compilation and/or revision and a few keywords to indicate the topical subject matter
Energy Technology Data Exchange (ETDEWEB)
Pan, Horng-Bin; Kuo, Li-Jung; Wai, Chien M.; Miyamoto, Naomi; Joshi, Ruma; Wood, Jordana R.; Strivens, Jonathan E.; Janke, Christopher J.; Oyola, Yatsandra; Das, Sadananda; Mayes, Richard T.; Gill, Gary A.
2015-11-30
High-surface-area amidoxime and carboxylic acid grafted polymer adsorbents developed at Oak Ridge National Laboratory were tested for sequestering uranium in a flowing seawater flume system at the PNNL-Marine Sciences Laboratory. FTIR spectra indicate that a KOH conditioning process is necessary to remove the proton from the carboxylic acid and make the sorbent effective for sequestering uranium from seawater. The alkaline conditioning process also converts the amidoxime groups to carboxylate groups in the adsorbent. Both Na2CO3-H2O2 and hydrochloric acid elution methods can remove ~95% of the uranium sequestered by the adsorbent after 42 days of exposure in real seawater. The Na2CO3-H2O2 elution method is more selective for uranium than conventional acid elution. Iron and vanadium are the two major transition metals competing with uranium for adsorption to the amidoxime-based adsorbents in real seawater.
Tax neutrality and the Saskatchewan Uranium Royalty
International Nuclear Information System (INIS)
Campbell, H.F.; Wrean, D.L.
1984-01-01
The effect of the Saskatchewan Uranium Royalty (SUR) on the extraction plans of uranium mining companies operating in Saskatchewan are discussed. The SUR consists of a basic royalty on the value of production and a graduated rate of return tax. Companies are also subject to federal and provincial income taxes. A model, based on the Key Lake mine in Australia, is used to determine whether the tax regime operating in Saskatchewan has the property of neutrality and effects the optimal extraction rate. Results show that SUR is a relatively low-cost means of collecting an economic rent from uranium mining and results in a lower extraction rate contributing to environmental protection in the province. (U.K.)
The costs of uncertainty: regulating health and safety in the Canadian uranium industry
International Nuclear Information System (INIS)
Robinson, I.
1982-04-01
Federalism, and particularly federal/provincial jurisdictional relationships, have led to considerable uncertainty in the regulation of occupational health and safety and of environmental protection in the Canadian uranium mining industry. The two principal uranium producing provinces in Canada are Saskatchewan and Ontario. Since 1978, in an attempt to avoid constitutional issues, both these provinces and the federal government as well have proceeded unilaterally with health and safety reforms for the industry. In Saskatchewan this has resulted in areas of overlapping jurisdiction, which have led to uncertainty over the legal enforceability of the provincial regulations. In Ontario, the province has left significant gaps in the protection of both workers and the environment. Little progress can be expected in eliminating these gaps and overlaps until the current administrative and jurisdictional arrangements are understood
Uranium and environment in Kazakstan
International Nuclear Information System (INIS)
Fyodorov, G.; Bayadilov, E.; Zhelnov, V.; Akhmetov, M.; Abakumov, A.
1997-01-01
Kazakstan's data on uranium as a state report has been included for the first time in the Red Book. Therefore the report contains two large themes presented in Suggested Topics for Papers: Country report, based on the 1995 NEA/IAEA Red Book Questionnaire and environmental impact regulations. Kazakstan is considered as one of the world leaders on uranium supply. In Kazakstan there are many well known types of deposits but the main one is the sandstone-rollfront type. That type is represented by the group of deposits of the Syr-Darya uranium ore province. Deposits of that type include that main part of uranium ore of the Republic of Kazakstan and supply almost all of its uranium mining. At the large three enterprises the uranium is extracted by underground leaching. The mining method of uranium extraction is stopped. Because of the poor development of nuclear energy, Kazakstan's need for uranium is not very high. Presence of a large amount of cheap and technological uranium ores allow the Republic to export uranium. There are plans to increase uranium mining and perhaps to establish new mining facilities including joint-ventures. More than 50 uranium deposits are known in Kazakstan. During prospecting and exploitation of these deposits a large amount of rad wastes in the form of ore dumps and tailings were generated. They have a substantial influence on the environment. Moreover, near the sandstone-rollfront type uranium deposits the large amount of underground water has been contaminated by radionuclides. Special investigation of this phenomenon is necessary. In Kazakstan there are the rad waste disposal conception and contaminated earth recultivation regulations. At present ''The Rad Wastes Management Law'' is submitted for approval. (author). 2 figs
International Nuclear Information System (INIS)
Yang Yaxin; Wu Yamei; Wu Xinmin; Chen Yue; Zheng Yongming; Zhang Ye; Wu Lieqin
2007-01-01
This paper briefly introduces the methods and procedures for field and indoor radon survey and themoluminescence (TL) survey. The application of these two methods to Xiazhuang uranium field in Guangdong province shows: (1) the positive anomalies of radon survey coincide well with fractured zone and the positive anomalies of TL survey response to uranium mineralization on granite type uranium deposit of silicated fracture zone, the uranium deposit can be effectively explored when these two kinds of anomalies match together. (2) the positive anomalies of radon survey coincide well with fractured zone and the positive anomalies of TL response to the position that intersection between the fractured zone and diabase dyke is projected on the ground. (authors)
Real-time measurement of electron beam weld penetration in uranium by acoustic emission monitoring
International Nuclear Information System (INIS)
Whittaker, J.W.; Murphy, J.L.
1991-07-01
High quality electron beam (EB) welds are required in uranium test articles. Acoustic emission (AE) techniques are under development with the goal of measuring weld penetration in real-time. One technique, based on Average Signal Level (ASL) measurement was used to record weld AE signatures. Characteristic AE signatures were recorded for bead-on-plate (BOP) and butt joint (BJ) welds made under varied welding conditions. AE waveforms were sampled to determine what microscopic AE behavior led to the observed macroscopic signature features. Deformation twinning and weld expulsion are two of the main sources of emission. AE behavior was correlated with weld penetration as measured by standard metallographic techniques. The ASL value was found to increase approximately linearly with weld penetration in BJ welds. These results form the basis for a real-time monitoring technique for weld penetration. 5 refs
International Nuclear Information System (INIS)
Danchev, V.I.; Komarnitskij, G.M.; Levin, V.N.; Shumlyanskij, V.A.
1985-01-01
Factors, affecting mineralization processes are considered. Characteristic features of uranium-bearing provinces are as follows: the presence of crust of continental type; deep-seated tectonic structures-rises and saggings, roofs, gneiss domes, rift zones and transform fractures; specialization for uranium of sedimentary and magmatic formations; the presence of manifestation regions of deep thermal and gaseous flow, etc. In uranium-bearing provinces territories favourable for the manifestation of different types of uranium mineralization: metamorphogenetic, polygenetic and exogenetic ones, are singled out. Different epochs of uranium ore formation are established. In sedimentary masses tectonic regime and climate are of special importance, and for epigenetic deposits, formed with an aid of underground waters-hydrogeological conditions. In the limits of the main structural elements of the Earth crust and geotectonic structures of higher orders the following types of sedimentary and volcanic formations can be singled out: 1-formations with exogenous uranium mineralization; 2-formations, accumulated in the epochs of epigenous ore formation; 3-formations fav ourable for epigenous uranium deposit formation; 4-formations unfavourable for the formation and localization of uranium mineralization
International Nuclear Information System (INIS)
Sinha-Roy, S.
2004-01-01
Evolution of the Precambrian terrain in Rajasthan has taken place via crustal consolidation of the basement at ca. 2.9 Ga, its cratonisation at ca. 2.5 Ga, through protracted tectonostratigraphic evolution of the Proterozoic cover sequences, following repeated rifting and Wilson cycles in the Aravalli and Delhi foldbelts. Consequently, the Proterozoic rift basins are characterised by growth faults and pull-aparts, and multitier volcanose dimentary sequences that contain a number of unconformities and stratigraphic breaks. The Archaean basement of the Mewar terrain that witnessed end-Archaean K-magmatism and ductile shearing, led to the creation of a possible uranium province, namely uranium enriched basement. This province acted as the source of remobilised uranium and its concentration at suitable multilevel structural and stratigraphic traps within the Proterozoic rift basins to give rise to unconformity-related syngenetic uranium mineralisation. Late Neoproterozoic to Pan-African tectonothermal reworking of the basement rocks produced fracture zones and caused Na-metasomatism giving rise to albitite-related uranium mineralisation. Based on an analysis of Proterozoic rift kinematics and lithofacies characteristics, five possible uranium-enriched stratigraphic horizons have been identified in the Aravalli and its equivalent sequences as well as in the North Delhi foldbelt sequences. From a regional synthesis, ten possible uranium metallogenic events, spanning ca. 2.5-0.5 Ga, are recognised in Rajasthan. These uranium events have predictive value for delineation of target areas for exploration. (author)
Covering soils and vegetations during decommissioning disposal of a uranium mine
International Nuclear Information System (INIS)
Feng Weihua
2010-01-01
The disposals of waste ore dumps and tailings are an important part in the decommissioning disposal of uranium mines. Important indexes of the disposal include stabilization, harmlessness, rehabilitation and improvement of the ecological environment. These are closely related with vegetations. Taking example of decommissioning disposal of a uranium mine in Guizhou province, the selection of grasses and effects after covering soils and planting grasses are introduced. It is pointed out that covering soils and vegetations play an important role in decommissioning disposal of uranium mines. (authors)
Applying reaction condition index to predict sandstone type uranium deposit
International Nuclear Information System (INIS)
Chen Gongxin; Liu Jinhui; Cheng Hai
2002-01-01
On the basic of the explanation of reaction condition index, the deduction of reaction condition index calculation principle, the hydrogeological setting in Gongpoquan basin in Baishan, Gansu province and the study of reaction condition index of its water source point, the north Luotuoquan area in Gongpoquan basin seems to be a favourable place for sandstone type uranium deposit, and the prospect area for sandstone type uranium deposit is delimitated
International Nuclear Information System (INIS)
Hu Zhihua; Lin Jinrong; Pang Yaqing; Gao Fei; Rong Jiashu; Guo Shuying
2013-01-01
Chlorite is genetically related to uranium mineralization in Huangnihu uranium deposit. By means of microscopic and electronic microprobe analysis, the authors investigated chemical composition and texture of the chlorite and found that chlorite in Huangnihu deposit has the following characteristics: 1. they are mainly Fe-rich chlorite composed of chamosite and brunsvigite, of which chemical composition is mainly affected by mud and mafic rock; 2. the Fe-Mg and Al"I"V-Si substitution dominates the octahedral substitution supplemented by Al"V"I-Fe substitution; the oolitic chlorite and biotite feinted chlorite closely associated with uranium were formed at temperatures of 216.23 ∼ 256.73℃ (average 228.6℃). The chemical composition and forming environment of the oolitic chlorite and biotite illusion chlorite suggests that Huangnihu uranium deposit is a low-moderate temperature hydrothermal uranium deposit formed in a reducing environment and iron-rich formation, the ore-forming fluid mainly originated from shale rock, partly from ultramafic or mafic liquid. (authors)
Public communication on times of environmental crisis. The opening of San Rafael 's uranium complex
International Nuclear Information System (INIS)
Calvino, Carlos; Cisneros, Martin
2008-01-01
Full text: Argentina has had a lot of cultural changes in the last few years. An environmental movement has gathered and is trying to stop the opening of the Sierra Pintada uranium complex, near the city of San Rafael, in the south of Mendoza province. Since 2005, several 'groundless information' have been published in the local media about the dangers of this re-opening. These news exaggerate the properties of radon gas, claiming that it will reach San Rafael city (20 miles from the complex), rising radiological risk among the population, etc. This scene shows a 'non-real' picture of the regulatory activities that the Nuclear Regulatory Authority (ARN), a government agency that regulates nuclear facilities in Argentina, is really and systematically accomplishing. In this situation, the board of Directors of ARN decided to entrust a full analysis of the environmental issue in the area. The Office of Press and Communication implemented a local communication plan, using a Strategic and Systemic tool kit. The period to be analyzed is from second semester 2005 to February 2007. A little bit of history: the San Rafael Complex started in September 20 of 1979. It belongs to the National Commission of Atomic Energy (CNEA), a government agency. Until its temporary suspension in 1995 for international market reasons (uranium price was U$S 10 / pound), almost 2 million tons of uranium were processed. Besides its temporary suspension, the ARN has been constantly monitoring this particular former complex. In the year 2001, CNEA notices that the uranium price starts to rise and entrust National Technology University, Avellaneda Branch, to accomplish an Environmental Impact Report, according to the argentine law 25.585. Due especially to the rising of uranium price, (actually, the uranium price is approximately U$S 200) the national government determined to restart the extraction of the mineral again. By the year 2004, with the results of the Environmental Impact report, CNEA
Analysis on uranium metallogenetic conditions of granite pluton in Ulan Uzhur
International Nuclear Information System (INIS)
Lu Yaozu
2014-01-01
Qimantage area in Qinghai province is one of the important exploration areas in the present China, Ulan Uzhur complex pluton, located in the compound tectonic magmatic belt of Qimantage, is the main cluster area with uranium mineralization. This paper describes the petrochemical, geochemical, petrophysical and Heishan uranium deposit mineralization characteristics of rocks formed at the different tectonic-magmatic cycles in Ulan Uzhur complex pluton. Uranium metallogenic conditions in Ulan Uzhur complex pluton were analyzed from uranium source, magmatic activity and structure. The research shew that the Ulan Uzhur complex pluton has the petrochemical characteristics of uranium rock and Cisuralian monzonitic granite has the most significant relationship to uranium mineralization, it has the characteristics of high background radiation, many anomalies and pronounced ore-control structure, Heishan uranium deposit was controlled by factors such as pronounced northeast and the northwest structure and alteration. To conclude, Ulan Uzhur complex pluton possesses good uranium metallogenic prospect. (author)
Investigation on uranium resources of Qinling region
International Nuclear Information System (INIS)
Peng Daming
1999-01-01
The Qinling Mountains straddle China from the west to the east with the length of more than 1300 km covering Anhui, Hubai, Hunan, Shanxi, Guansu, Qinghai and Sichuan provinces. Up to now, 20 uranium deposits have been discovered in the region and all discovered deposits can be classified into 3 type (granite type, sedimentation-reworking type and hydrothermal alteration type) and 9 subtypes including 15 uranium deposits discovered in Qinling geosyncline area. Main uranium deposits are concentrated in Danfeng and Shangnan counties, southern Shanxi, lantian county, central Shanxi and Lixian County, Southern Gansu. Of the above listed uranium deposits, the granite-hosted deposits are most important, and characterized by large resources, high grade of ore and easiness in hydrometallurgy. Sedimentation-reworking type deposits are less important. The main U-metallogenic epoch is the Caledonian and the Yanshanian is the second. A prognosis for uranium deposits in Qinling region is made in the paper which proposes that the belt from Dangchuan in the west, via Jiamusi, Gepai and Fenshuling to Longquanping in the east is a most favorable area for location granite type uranium deposits
Energy Technology Data Exchange (ETDEWEB)
Pan, Horng-Bin [Department of Chemistry, University of Idaho, Moscow, Idaho 83844 USA; Wai, Chien M. [Department of Chemistry, University of Idaho, Moscow, Idaho 83844 USA; Kuo, Li-Jung [Pacific Northwest National Laboratory, Marine Sciences Laboratory, Sequim, Washington 98382 USA; Gill, Gary [Pacific Northwest National Laboratory, Marine Sciences Laboratory, Sequim, Washington 98382 USA; Tian, Guoxin [Lawrence Berkeley National Laboratory, Berkeley, California 94720 USA; Rao, Linfeng [Lawrence Berkeley National Laboratory, Berkeley, California 94720 USA; Das, Sadananda [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 USA; Mayes, Richard T. [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 USA; Janke, Christopher J. [Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 USA
2017-05-02
Uranium adsorbed on amidoxime-based polyethylene fibers in simulated seawater can be quantitatively eluted using 3 M KHCO3 at 40°C. Thermodynamic calculations are in agreement with the experimental observation that at high bicarbonate concentrations (3 M) uranyl ions bound to amidoxime molecules are converted to uranyl tris-carbonato complex in the aqueous solution. The elution process is basically the reverse reaction of the uranium adsorption process which occurs at a very low bicarbonate concentration (~10-3 M) in seawater. In real seawater experiments, the bicarbonate elution is followed by a NaOH treatment to remove natural organic matter adsorbed on the polymer adsorbent. Using the sequential bicarbonate and NaOH elution, the adsorbent is reusable after rinsing with deionized water and the recycled adsorbent shows no loss of uranium loading capacity based on real seawater experiments.
Discovery of the Sierra Pintada uranium district, Mendoza Province, Argentina
International Nuclear Information System (INIS)
Rodrigo, F.; Belluco, A.E.
1981-01-01
Since 1956, uranium-bearing minerals have been known to exist in Sierra Pintada, Mendoza Province, Argentina. Based on paragenetic considerations, a first radiometric prospection was carried out, leading to the discovery of two groups of anomalies (Puesto Agua del Toro and Cuesta de los Terneros), such as vein-type deposits, with uraninite and 'yellow minerals' and one sandstone-type deposit (Puesto La Josefa), related to sediments with carbon trash. Some recent geological research and surveys in the area, and a reduced drilling programme carried out on selected anomalies, led to reinterpretation of the potential of the area. Furthermore, and as a result of an airborne radiometric prospection performed in mid-1968, numerous anomalies have been discovered. The main constellation of anomalies, along the flanks of the El Tigre Brachyanticline, occurs in sandstones of Permian age. Explored by 80 000 m of drilling, they have shown the existence of several peneconcordant lens-shaped ore bodies of economic size, with uranophane on the surface and prevailing uraninite and some brannerite, coffinite and davidite below the water table. Reserves exceed 20 000 tonnes of U 3 O 8 . A new regional programme with a 4-km drill-grid initiated in 1978 led to the discovery of new ore bodies which are at present being evaluated. The alternatives and discontinuities during the development of the district, the prospecting and exploration techniques employed, and the results achieved in the different stages of the operation are discussed in detail. This case history attempts to illustrate the developing philosophy which was successfully applied in Sierra Pintada, with emphasis on the following points: (a) the need for adequate geological knowledge of the area; (b) the advantage of a massive survey (in this case, air survey); (c) the necessity for exploration (drilling) in order to define the anomalies and make their evaluation possible; and (d) the convenience of extending exploration
A coalescence model for uranium exploration
International Nuclear Information System (INIS)
Stuart-Williams, V.; Taylor, C.M.
1983-01-01
Uranium mineralization was found in the Pristerognathus-Diictodon Assemblage Zone of the Teekloof Formation, Beaufort Group, west of Beaufort West, Cape Province, South Africa. All the anomalies can be related to a single mineralization model. Mineralization is found at the termination of a silt parting between two coalescing sandstones and lies in the lower sandstone as an inclined zone dipping downflow from the termination of the silt parting. The existence of primary Eh-pH gradient is indicated by a uranium-molybdenum zonation, the molybdenum lying above the uranium mineralization. The upper sandstone was an oxidizing fluvial channel in an arid environment through which uranyl carbonate was being transported in solution. Carbonaceous material undergoing anaerobic bacterial breakdown generated a weakly reducing fluid in the lower sandstone. Carbonaceous material at the REDOX front developed between the two mixing fluids at the point of sandstone coalescence reduced uranyl carbonates in solution. Once reduced the uranium minerals remained stable because the conditions in the REDOX front were only very weakly oxidizing. As floodplain aggradation continued, the upper sandstone was buried and the entire sandstone couplet became reducing, permanently stabilizing the uranium mineralization
National uranium resource evaluation: Clifton Quadrangle, Arizona and New Mexico
International Nuclear Information System (INIS)
White, D.L.; Foster, M.
1982-05-01
The Clifton Quadrangle, Arizona and New Mexico, was evaluated to identify environments and delineate areas favorable for uranium deposits. The evaluation used criteria formulated for the National Uranium Resource Evaluation program. Evidence for the evaluation was based on surface studies, hydrogeochemical and stream-sediment reconnaissance, and aerial radiometric surveys. The quadrangle encompasses parts of three physiographic provinces: the Colorado Plateau, the transition zone, and the Basin and Range. The one environment determined, during the present study, to be favorable for uranium deposits is the Whitewater Creek member of the Cooney tuff, which is favorable for magmatic-hydrothermal uranium deposits on the west side of the Bursum caldera. No other areas were favorable for uranium deposits in sandstone, limestone, volcanogenic, igneous, or metamorphic environments. The subsurface is unevaluated because of lack of information, as are areas where access is a constraint
Evolution of ore-bearing material sources of endogenous uranium deposits
International Nuclear Information System (INIS)
Kazansk, V.I.; Laverov, N.P.; Tugarinov, A.I.
1976-01-01
Considered are the regularities of changes in types and conditions of uranium deposit formation in connection with the general development of the earth crust tectonic structures. Out of pre-Kembrian uranium deposits considered are Vitwatersrand conglomerates, hydrothermal deposits in pre-Kembrian iron quartzites in the areas of regional fractures in exocontacts of big multiphase granitoid massifs of Proterozoic age and in the fundament folded structures. The hydrothermal-metamorphogen theory is supported of the origin of uranium-bearing sodium metasomatite of Proterozoic, including uranium deposits in the area of the Atabaska lake. Four genetic classes of Palaeozoic deposits are considered. Four periods are singled out in the development of Palaeozoic uranium provinces. Most of the Palaeozoic deposits are shown to be of polygenous origin. Mesozoic deposits are also polygenous, but the combination of ore substance sources in them is more complex
Lagoa Real design. Cachoeira mine. Uranium ratio from gamma profile
International Nuclear Information System (INIS)
Juliao, B.
1984-06-01
This paper presents the satisfactory accuracy of uranium ratio from gamma profile, using an equation from simple regression. The comparative study between radiometric ratios calculated from gamma data in boreholes and uranium ratio determined by Delayed Neutron Analysis shows a good measure of correlation in Cachoeira Mines. (author)
Uranium metallogeny, magmatism and structure in southeast China
International Nuclear Information System (INIS)
Simpson, P.R.
1989-01-01
Granite magmatism and the associated uranium metallogeny in southeast China are considered in relation to a plate tectonic model previously developed for Jiangxi Province which envisages the suturing of three separate continental fault blocks or plates which are thought to have existed as separate continental microplates until the Permian, namely the Sino-Korean, Yangtze and South China Plates. In Jiangxi Province, most of the granitic magmas, including those considered in the paper to be associated with U ore deposits, can be shown to be systematically distributed in relation to the postulated destructive plate margins which are thought to have existed along all the plate boundaries between the continental microplates. The granitic intrusions in Jiangxi range from those more proximal to the inferred location of the subduction zone in a modified Andean type model, such as porphyries of Cu, Cu-Mo and W-Cu type, to more distal granites of U-W-Sn-F-Nb-REE type. They range in age from Indosinian to Yanshanian (but mainly the latter) and are intruded in tensional settings along major lithospheric fracture zones, with sinistral strike slip, many of which continued to move both during and after granite emplacement. These U, W, Sn, F, Nb and REE rich metalliferous granites, which all intruded post-tectonically long after the principal metamorphic events, which are Jinningian (Late Proterozoic on the Yangtze Plate) and Caledonian (South China Plate), and the younger suturing events, are considered in the study to be essentially of juvenile magmatic rather than crustal origin. Such a tectonic model helps to account for the well developed and structurally zoned metallogeny of southeast China and the genesis of the Southeast China Uranium Province. Selected examples of U ore deposits which occur within the Southeast China Uranium Province are considered in order to develop the basis for a genetic model for U which would be more generally applicable to this region and possibly
National Uranium Resource Evaluation: Athens Quadrangle, Georgia and South Carolina
International Nuclear Information System (INIS)
Lee, C.H.
1979-09-01
Reconnaissance and detailed geologic and radiometric investigations were conducted throughout the Athens Quadrangle, Georgia and South Carolina, to evaluate the uranium favorability using National Uranium Resource Evaluation criteria. Surface and subsurface studies were augmented by aerial radiometric surveys, emanometry studies and hydrogeochemical and stream-sediment reconnaissance studies. The results of the investigations indicate environments favorable for allogenic deposits in metamorphic rocks adjacent to granite plutons, and Texas roll-type sandstone deposits in the Coastal Plain Province. Environments considered unfavorable for uranium deposits are the placers of the Monazite Belt, pegmatites, and base- and precious-metal veins associated with faults and shear zones in metamorphic rocks
International Nuclear Information System (INIS)
2006-01-01
Industry revenue, which rose very strongly in the mid 2000s on the back of higher prices and higher production, is expected to retreat during the outlook i period. Indications are that a small gain in real industry revenue will be made in 2007-08, reflecting slightly higher output and some- what higher Australian dollar contract prices. However, real industry revenue is then expected to fall over the remaining years of the out- , look period, as output and exports edge lower and prices ease. Production from Ranger is expected to ease as mining winds down and the operation becomes ore processing only, and no new mines or mine expansions will come on stream over this relatively short period. Large increases in spot uranium prices in the mid 2000s were driven by falling uranium stocks, increased concern over future uranium supplies and growing speculative demand for uranium. Despite very large price rises, world uranium production responded only slowly, reflect-ing the long lead-time required to either expand existing operations or bring new developments on stream
International Nuclear Information System (INIS)
Matar, M.; Arroqui, A.; Wetten, A.; Banchig, P.; Iglesias, R.
2010-01-01
Preliminary results of research carried out in the area of Medano Rico, Dto Jachal San Juan Province, under the project Implementation of a model for exploration of uranium in Pre cordillera describes this work. The research tasks are intended to deepen the knowledge of the area to establish a genetic model of uranium anomaly
International Nuclear Information System (INIS)
Warner, R.F.; Pickup, G.
1982-01-01
This paper describes the principal landforms of the Alligator Rivers Region Uranium Province of Northern Australia, reviews work on landforms and processes in this wet and dry tropical environment, and discusses the kinds of geomorphological hazards which might be encountered in disposing of uranium tailings at the Nabarlek, Ranger, Koongarra and Jabiluka Uranium Project Sites
Energy Technology Data Exchange (ETDEWEB)
Santos, Camila Marques dos
2016-07-01
In the northwestern portion of the Lagoa Real Uranium Province (LRUP), located in south-central Bahia, it is located one of the most promising uranium anomalies Brazil (an35, Gameleira I deposit), the reserves and proximity to the Cachoeira mine. Other anomalies of this sector (eg. 31 AN and AN34), are also considered strategic for the content of radioactive minerals and REE. The objective was to develop a study of a representative drill core of an35, where the main rocks PULR are present. The research focused on the mineralogical and chemical changes observed in the passages of a lithology to another, from the rock to the meta granitic albitites, through gneiss and transitional rocks, and making comparisons with similar lithologies sampled on testimonies of AN31 and 34. The granites are classified as hypersolvus coarse alkali-feldspar granite and are variably deformed. The main mineral assemblage in granites are perthitic orthoclase+hedenbergite+ quartz +hastingsite + biotite, and zircon, apatite, ilmenite and titanite are accessories. The reddening of these rocks are characterized by feldspars sericitization and hematitization and the presence of 'vazios'. The gneisses are mainly gray and reach milonitic to protomilonitics terms. These rocks have characteristics of subsolidus changes as swapped rims and metasomatic perthites. The tardi-magmatic association (amphibole+biotite) indicates final crystallization or late influx by superficial fluids resulting in an increase in water and volatiles, such as F and Cl in the system, which must also have carried rare-earth elementsGranites have geochemical affinity with A-type ferroan granite, A2, reduced and are post-collisional. Their patterns of incompatible elements and rare earths are comparable to Sao Timoteo Granite, but their petrographic features indicate that it is a less common granite facies. Albitites were classified as garnet albitites, magnetite albitites and biotite albitites. Contacts between
A mathematical model to forecast uranium production
International Nuclear Information System (INIS)
Camisani-Calzolari, F.A.G.M.
1987-01-01
The uranium production forecasting program described in this paper projects production from reasonably assured, estimated additional and speculative resources in the cost categories of less than $130/kg U. Originally designed to handle South African production, it has been expanded and redimensioned using available published information to forecast production for countries of the Western World. The program forecasts production from up to 400 plants over a period of fifty years and has built-in production models derived from documented historical data of the more important uranium provinces. It is particularly suitable to assess production capabilities on a national and global scale where variations in outputs for the individual plants tend to even out. The program is aimed at putting the uranium potential of any one country into a realistic perspective, and it could thus be useful for planning purposes and marketing strategies
International Nuclear Information System (INIS)
Huang Hongye; Huang Sidong; Cai Songfeng
2008-01-01
Lujing area is an important uranium metallogenic zone in China. Based on summarizing the geological background of Lujing uranium ore-field, it is analyzed that deep origin metallogenesis, deep-seated strike-slip faults, thermal metamorphic belt and granite-porphyry play important roles in uranium mineralizatiom. It is pointed out that the NNE to NE-trending Suichuan-Reshui left-handed strike-slip fault controls directly the sedimentary characteristics, tectonic framework and uranium metallogenesis. For the discovered deposits and occurrences, it needs to study in the view of deep origin metallogenesis and ore-control by deep-seated strike-slip fault, do more further research on their evolutionary features and coupling types. It also needs to explore new types, discover new favorable area, predict and optimize the break-through prospecting target so as to make scientific assesment on the uranium resources potentialities of the ore-field and its peripheral area. (authors)
Uranium determination in water
International Nuclear Information System (INIS)
Prudenzo, E.J.; Puga, Maria J.; Cerchietti, Maria L.R.; Arguelles, Maria G.
2005-01-01
In our laboratory, a procedure has been assessed to determine uranium content of water in normal situations. The method proposed without sample pre-treatment, is simple and rapid. Uranium mass is measured by fluorimetry. For calculation of detection limit (Ld) and quantification level (Lq) we used blank samples and the results were analyzed for different statistical test. The calculation of total propagated uncertainty and sources contribution on real samples are presented. (author)
U-Pb ages related to uranium mineralization of Lagoa Real, Bahia - Brazil: tectonic implications
Energy Technology Data Exchange (ETDEWEB)
Chaves, Alexandre O.; Rios, Francisco J.; Oliveira, Lucilia A.R.; Alves, James V.; Fuzikawa, Kazuo; Neves, Jose M.C.; Chaves, Adriana M.D.V.; Prates, Sonia P. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)]. E-mail: aoc@cdtn.br; Tubrett, Michael [Memorial University of Newfoundland, NL (Canada). Inco Innovation Centre. MicroAnalysis Facility; Matos, Evando C. [Industrias Nucleares do Brasil S.A. (INB), Rio de Janeiro, RJ (Brazil)
2007-07-01
The uranium from Lagoa Real (Bahia/Brazil) is associated with syenitic magmatism (1904 {+-}44 Ma minimum age from upper intercept of zircon U-Pb discordia by LA-ICP-MS) belonging to a mafic/ felsic lithologic association linked to the final stages of 2.05-1.80 Ga Orosirian Orogeny, which acted in the Paramirim Block. These syenitic rocks are rich not only in albite, but also in U-rich titanite (source of uranium). In association with the development of the Orosirian ductile shear zones, the syenites were crystallized and deformed. The metamorphic reactions, which include intense recrystallization of magmatic minerals, led uraninite to precipitate (1868 {+-} 69 Ma; U-Pb by LA-ICP MS) under Redox control. A second population of uraninites was also generated by shear zones reactivation during 0.6-0.5 Ga Brasiliano Orogeny (605 {+-} 170 Ma; U-Pb by LA-ICP-MS). The geotectonic implications are: a) the importance of the Orosirian event in the Paramirim Block during paleoproterozoic Sao Francisco/Congo Craton edification and b) the influence of the Brasiliano event in the Paramirim Block during the West-Gondwana assembly processes, indicated by the 605 {+-} 170 Ma uraninite (second population) age and by the 483 {+-} 100 Ma lower intercept of the metamorphosed syenite U-Pb discordia. (author)
South African gold and uranium ore mining in 1976
International Nuclear Information System (INIS)
Hentrich, W.
1977-01-01
1976 was a difficult year for the South African gold and uranium ore mining industry, the region of Witwatersrand (Transvaal province) producing some 75% of all the gold mined in the western world besides being an important producer of uranium oxide. Despite the gold production, declining since 1971, not showing a downward tendency anymore as far as the quantity was concerned, the economic result, however, deteriorated as a consequence of continuously falling gold prices, but also on account of the inflationary rise in wages and the prices for energy and materials. Much higher prices for uranium oxide, which some mines produce as interim products from the 'degolded' slurries of their gold ore leaching plants, improved the economic overall result only to a small degree. (orig.) [de
Uranium occurrences in the surficial deposits of Southern Africa
International Nuclear Information System (INIS)
Hambleton-Jones, B.B.
1982-01-01
This paper outlines the geology of the Tertiary to Recent(10 to 0,1 Ma) surficial uranium deposits in South West Africa/Namibia and South Africa. They occur mainly in the Namib Desert to the east of Walvis Bay in South West Africa/Namibia and in the north-western Cape Province of South Africa. All the deposits can be classified as fluviatile, lacustrine/pan, or pedogenic types. The economic potential of the surficial uranium deposits in the north-western Cape is insignificant compared with their South West African/Namibian counterparts. Most of the deposits occur in gypsiferous fluviatile gravels and lacustrine/pan sediments. The largest of the deposits is a lacustrinal, peat-rich, diatomaceous earth type. The mechanisms for the precipitation of the uranium are discussed
Uranium mineralization associated with late Palaeozoic acid magmatism in northeast Queensland
International Nuclear Information System (INIS)
Bain, J.H.C.
1977-01-01
The late Palaeozoic acid igneous petrographic province, covering some 120,000 km 2 in the Cairns-Townsville hinterland, has associated uranium mineralization characterized by various combinations of uranium, fluorine, and molybdenum. Mineralization of this type has been described from other parts of the world, but is best known in the USSR. Information about the Australian deposits and occurrences is very limited, but it is apparent that the mineralization is mainly of hydrothermal origin and genetically related to extensive late Palaeozoic magmatism. A detailed description of the mineralization and the prospect of additional discoveries of uranium deposits of similar and related types in other parts of Australia are discussed. (J.R.)
Energy Technology Data Exchange (ETDEWEB)
Pestana, Rafael C.B.; Sarkis, Jorge E.S.; Carvalho, Elita F.U., E-mail: rcbpestana@gmail.com, E-mail: jesarkis@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Abreu Junior, Cassio H. [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil)
2013-07-01
Environmental swipe sampling for safeguards purposes is a powerful tool to detect undeclared materials and activities, and has been used by the International Atomic Energy Agency since 1997. This work describes the utilization of the inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for determining uranium isotopic ratios in a real-life swipe samples collected in a conversion plant at IPEN/CNEN, Brazil. Uncertainties were estimated by following the International Organization for Standardization - Guide to the Expression of Uncertainties in Measurement (ISO GUM), with a confidence level of 95%. The major uncertainties percentage for n({sup 235}U)/n({sup 238}U) ratio for ICP-MS was 3% and for LA-ICP-MS was 30% The values of uranium isotopic ratios obtained for each technique demonstrate the viability of these analytical techniques as an alternative tool for uranium analysis in swipe samples for safeguards purposes. (author)
International Nuclear Information System (INIS)
Pestana, Rafael C.B.; Sarkis, Jorge E.S.; Carvalho, Elita F.U.; Abreu Junior, Cassio H.
2013-01-01
Environmental swipe sampling for safeguards purposes is a powerful tool to detect undeclared materials and activities, and has been used by the International Atomic Energy Agency since 1997. This work describes the utilization of the inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for determining uranium isotopic ratios in a real-life swipe samples collected in a conversion plant at IPEN/CNEN, Brazil. Uncertainties were estimated by following the International Organization for Standardization - Guide to the Expression of Uncertainties in Measurement (ISO GUM), with a confidence level of 95%. The major uncertainties percentage for n( 235 U)/n( 238 U) ratio for ICP-MS was 3% and for LA-ICP-MS was 30% The values of uranium isotopic ratios obtained for each technique demonstrate the viability of these analytical techniques as an alternative tool for uranium analysis in swipe samples for safeguards purposes. (author)
International Nuclear Information System (INIS)
1987-09-01
Canadian uranium exploration and development efforts in 1985 and 1986 resulted in a significant increase in estimates of measured uranium resources. New discoveries have more than made up for production during 1985 and 1986, and for the elimination of some resources from the overall estimates, due to the sustained upward pressure on production costs and the stagnation of uranium prices in real terms. Canada possesses a large portion of the world's uranium resources that are of current economic interest and remains the major focus of inter-national uranium exploration activity. Expenditures for uranium exploration in Canada in 1985 and 1986 were $32 million and $33 million, respectively. Although much lower than the $130 million total reported for 1979, expenditures for 1987 are forecast to increase. Exploration and surface development drilling in 1985 and 1986 were reported to be 183 000 m and 165σ2 000 m, respectively, 85 per cent of which was in Saskatchewan. Canada has maintained its position as the world's leading producer and exporter of uranium. By the year 2000, Canada's annual uranium requirements will be about 2 100 tU. Canada's known uranium resources are more than sufficient to meet the 30-year fuel requirements of those reactors in Canada that are either in operation now or expected to be in service by the late 1990s. A substantial portion of Canada's identified uranium resources is thus surplus to Canadian needs and available for export. Annual sales currently approach $1 billion, of which exports account for 85 per cent. Forward domestic and export contract commitments totalled 73 000 tU and 62 000 tU, respectively, as of early 1987
Central Ukraine Uranium Province: The genetic model
International Nuclear Information System (INIS)
Emetz, A.; Cuney, M.
2014-01-01
Ukraine produces ~1,100 t U per year from the Michurinske, Centralne, Novokostantynivske and Vatutinske U deposits in the Kirovograd U district of the Central Ukraine Uranium Province (CUUP) consisting of about 20 deposits and numerous showings related to ~1.8 Ga sodium metasomatites developed in the Lower Paleoproterozoic granite-gneiss and iron formations of the Ingul Megablock of the Ukrainian Shield. Two deposits (the Zhovta Richka and Pervomayske) were mined out tens kilometers eastward in iron formations of the Kryvy Rig – Kremenchug mining district. Nametasomatite fields with scarce sub-economical U-mineralization were revealed by geophysical (magnetometry and gravimetry) and drilling programs northward in granitised gneisses around the younger Korsun-Novomyrgorod rapakivi pluton consisting of A2-type within plate granitoids which were emplaced during decompression melting at ~1.75 Ga. The present work aims to demonstrate structural and geochemical factors related to Na-metasomatism, and to mark out geochemical and tectonical parameters which were favorable for U-accumulation using data on deep seismic survey, geological structure analysis, and mineralogical and geochemical investigations of metasomatites. In the Ingul Megablock, Na-metasomatites occur along shear fault zones mostly oriented N-S. Metasomatites form complicate systems of plate- and lens-like bodies of aegirine-riebeckite albitites surrounded by dequartzified host rocks. Elemental alteration during Na-metasomatism demonstrates simple exchange of Si, K, Rb, Ba and Cs by Na, Ca, and locally V and U. δ 18 O H 2 O (300-400ºC) for albitizing hydrothermal solutions is near “zero”, typically for surficial water. These data suggest host rock interaction with hot marine waters. Persistent Na-metasomatic alterations extend along major tectonic faults for several kilometres with variable thicknesses reaching some hundreds meters in the zones of intense brecciation developed in the places of fault
International Nuclear Information System (INIS)
Thamm, J.K.; Kovschak, A.A. Jr.; Adams, S.S.
1981-01-01
The uranium-vanadium deposits of the Salt Wash Member of the Morrison Formation in the Colorado Plateau are similar to sandstone uranium deposits elsewhere in the USA. The differences between Salt Wash deposits and other sandstone uranium deposits are also significant. The Salt Wash deposits are unique among sandstone deposits in that they are dominantly vanadium deposits with accessory uranium. The Salt Wash ores generally occur entirely within reduced sandstone, without adjacent tongues of oxidized sandstone. They are more like the deposits of Grants, which similarly occur in reduced sandstones. Recent studies of the Grants deposits have identified alteration assemblages which are asymmetrically distributed about the deposits and provide a basis for a genetic model for those deposits. The alteration types recognized by Shawe in the Slick Rock district may provide similar constraints on ore formation when expanded to broader areas and more complete chemical analyses
International Nuclear Information System (INIS)
Shen Feng
1995-01-01
After over 30 years' development, uranium resources exploration work in China has resulted in the discovery of more than 10 economic types of uranium deposits in 23 provinces (regions) of the whole country and large quantities of uranium reserves have been submitted which guarantee the development of nuclear industry in China. However, characteristics such as smaller size of deposits and ore bodies, and lower ore grade of discovered China's uranium deposits have brought about a series of problems on how to economically exploit and utilize these uranium resources. To prospect for superlarge uranium deposits is a guarantee of making uranium resources essentially meet the demand for the long-term development of nuclear industry in China, and is an important way of improving economic benefits in mining China's uranium resources. It is an important mark for uranium geological exploration work to go up a new step as well. China exhibits the geological environment in which various types of superlarge uranium deposits can be formed. Having the financial support from the state to uranium resources exploration work, having professional uranium exploration teams well-experienced in ore prospecting, having modernized uranium exploration techniques and equipment and also having foreign experience in prospecting for superlarge uranium deposits as reference, it is entirely possible to find out superlarge uranium deposits in China at the end of this century and at the beginning of next century. In order to realize the objective, the most important prerequisite is that research work on metallogenetic geological theory and exploration techniques and prospecting methodology for superlarge uranium deposits must be strengthened, and technical quality of the geological teams must be improved. Within this century, prospect targets should be selected and located accurately to carry out the emphatic breakthrough in exploration strategy
International Nuclear Information System (INIS)
Woods, R.J.
1981-01-01
This report surveys the views of those associated with uranium mining in northern Saskatchewan on the research needs of the industry. Research resources, both human and material, available in the province are outlined. The author makes recommendations that would lead to a viable uranium research program. Appendices list information on current uranium-related research in Saskatchewan and available research resources
An improved FT-TIMS method of measuring uranium isotope ratios in the uranium-bearing particles
International Nuclear Information System (INIS)
Chen, Yan; Wang, Fan; Zhao, Yong-Gang; Li, Li-Li; Zhang, Yan; Shen, Yan; Chang, Zhi-Yuan; Guo, Shi-Lun; Wang, Xiao-Ming; Cui, Jian-Yong; Liu, Yu-Ang
2015-01-01
An improved method of Fission Track technique combined with Thermal Ionization Mass Spectrometry (FT-TIMS) was established in order to determine isotope ratio of uranium-bearing particle. Working standard of uranium oxide particles with a defined diameter and isotopic composition were prepared and used to review the method. Results showed an excellent agreement with certified values. The developed method was used to analyze isotope ratio of single uranium-bearing particle in swipe samples successfully. The analysis results of uranium-bearing particles in swipe samples accorded with the operation history of the origin. - Highlights: • The developed method was successfully applied in the analysis of real swipe sample. • Uranium-bearing particles were confined in the middle of track detector. • The fission tracks of collodion film and PC film could be confirmed each other. • The thickness of collodion film should be no more than about 60 μm. • The method could avoid losing uranium-bearing particles in the etching step.
uranium and thorium exploration by geophysical methods
International Nuclear Information System (INIS)
Yueksel, F.A.; Kanli, A.I.
1997-01-01
Radioactivity is often measured from the ground in mineral exploration. If large areas have to be investigated, it is often unsuitable to carry out the measurements with ground-bound expeditions. A geophysical method of gamma-ray spectrometry is generally applied for uranium exploration. Exploration of uranium surveys were stopped after the year of 1990 in Turkey. Therefore the real potential of uranium in Turkey have to be investigated by using the geophysical techniques
The design on high slope stabilization in waste rock sites of uranium mines
International Nuclear Information System (INIS)
Liu Taoan; Zhou Xinghuo; Liu Jia
2005-01-01
Design methods, reinforcement measures, and flood control measures concerning high slope stabilization in harnessing waste rock site are described in brief according to some examples of two uranium mines in Hunan province. (authors)
International Nuclear Information System (INIS)
Chen Zhuhai; Zheng Mingliang; Song Shizhu; Liang Yewu; Zhao Wei
2008-01-01
Heyuan mineralization belt is a structure-magmatic activities belt which is charcterized by strong plastic deformation and shearing. The squeeze (overthrust) structure is formed early. Later stretch produced slide shovel-shaped normal fault which control the red basin and uranium mineralization. Comprehensive study shows that this area is of favorable uranium metallogenic condition due to the rich uranium source and higher degree of geology work, it is a target for the new round resources exploration. (authors)
Sandstone uranium deposits of Eurasia – from genetic concepts to forecasting and new discoveries
International Nuclear Information System (INIS)
Pechenkin, I.
2014-01-01
Along the Eurasian continent’s southern borders lie uranium ore provinces and regions controlling medium-sized and, on rare occasions, large sandstone deposits. Central French, Eastern Rhodope and other regions are known in the west. Large uranium ore provinces were discovered in the south of the Turan Plate and in the depressions of South Kazakhstan, viz. Central Kyzyl Kum, Syr Darya, Chu Sarysu. A common criterion has been established for all objects of the sandstone type, located in oil and gas, coal etc. sedimentary basins – the zone of interlayer or ground-interlayer oxidation, controlling uranium mineralization. In 2003 we were able to justify the concept that the formation of giant deposits in Chu Sarysu province was caused by the collision between the Indian Plate and the southern part of the Eurasian continent. Within the limits of Pacific ore belt there is a zonal distribution of ore deposits. Ordinary mineralization is drawn towards its eastern fringe: gold, tin, copper, tungsten etc. Volcanic and tectonic structures of central type of Mesozoic age are located further west, from the north to the south, that is large calderas – Streltsovskaya (Russia), Dornot (Mongolia), Sian Shan (China), which control large and unique endogene uranium deposits. In the far west, in the region of subsiding tectonic tensions, there are sandstone deposits of uranium in Transbaikalia, Mongolia and Yunnan, which are specially connected to young basalts. Infiltration deposits of Vitim region are adjacent to endogene deposits of Streltsovsky region in the southern-easterly direction, and to the east of the deposits of Yunnan at the same latitude lay the Sian Shan caldera with geothermal deposits of uranium and other metals. We combined them into the unified submeridional Baikal-Southern China uranium ore belt. After examining the southern extremities of the Eurasian continent, the region of the collision of the Indian Plate, a distinct similarity can be perceived between
Critique of the Saskatchewan Uranium Royalty in the light of neutral taxation
International Nuclear Information System (INIS)
Kwon, O.Y.
1982-01-01
The Saskatchewan Uranium Royalty System, in operation since 1976, is the provincial government's prime policy vehicle towards the uranium industry. The enunciated objectives of the royalty system are (Sask., 1977): (a) to ensure a minimum return to the province from the extraction of uranium; (b) to capture a fair share of the ''excess'' profits; (c) to provide the producers with an adequate rate of return on investment; and (d) to leave marginal production decisions unaffected. The purpose of this paper is to evaluate the royalty system in light of these objectives. This article evaluates neutral taxation and how it effects the Saskatchwan Royalty System
International Uranium Resources Evaluation Project (IUREP) national favourability studies: Malaysia
International Nuclear Information System (INIS)
1977-12-01
Malaysia is a country of 330,000 square kilometers and a population of 11.9 million. The country is divided into two parts 640 kilometers apart. West Malaysia consists of the Malay Peninsula, and East Malaysia of the provinces of Sarawak and Sabah, formerly North Borneo. The country is the world's leading producer of tin and rubber. Geologic descriptions in detail are difficult to find although maps are available. Uranium exploration, chiefly by the Malaysian Geological Survey, has been carried out without discovery of commercial quantities. Based on possible recovery of uranium from deeply weathered granites on the Malay Peninsula, and possible discoveries in East Malaysia, a uranium potential of 1,000 to 10,000 tonnes U (category 2) is assigned. (author)
Low grade uranium ores as potential sources of raw material
International Nuclear Information System (INIS)
Venzlaff, H.
1976-01-01
Reports on the uranium requirement and the uranium reserves show that, even if the demand were to be stretched out slightly, the rate of new discoveries of uranium would have to be doubled or even tripled within a few years in order to ensure supply. Despite some spectacular discoveries of large scale deposits in Australia it must be said that only very few truly new uranium provinces have been discovered over the past twenty years. In this situation more attention is now being devoted to low grade uranium depositis, to findings whose concentration does not exceed 1,000 ppm. These deposits contain quantities of uranium many times larger than the deposits that can now be mined at prices up to 30/lb of U 3 O 8 . Even now low grade uranium ore is being mined as a byproduct, with the actual valuable mineral producing most of the income from mining activities. However, if one strikes a balance in this situation, one finds that only part of the requirement can be met in this way. Hence, all possibilities must be exhausted to mine uranium as a byproduct, new techniques of uranium production from low grade ores must be developed, and also conventional prospection must be intensified, if the continuity of supply of the nuclear power stations in the eighties and nineties is to be guaranteed. (orig.) [de
Uranium distribution and availability
International Nuclear Information System (INIS)
Bowie, S.H.U.
1977-01-01
Uranium deposits are not uniformly distributed in the earth's crust but occur in well-defined provinces, mainly in Precambrian terrain and in association with acid igneous rocks. Deposits can conveniently be classified into four main groups; uranium in sandstones; uranium in conglomerates; vein-and similar-type deposits; and other uranium deposits. Most of the presently known reserves occur in sandstones; vein-type deposits are now second in importance; conglomerates are third and other deposits, excluding shales, fourth. The shales of southern Sweden constitute a special case; although recoverable reserves are large (300 000 t U), annual production from them is not likely to exceed 1000 to 2000 t U. The estimation of reserves has been complicated by rapid price rises since 1973 and by uncertainty as to what cost or price levels should be adopted in distinguishing between reserves and resources. Also there has been a tendency for requirements to be revised downwards, and this, together with the apparent acceptance of cost levels of around $30/lb U 3 O 8 , has relieved the medium-term prospects so far as supply is concerned. In the longer term, however, there is clearly a need for increased prospecting effort on a world scale and for the introduction of new search methods, particularly those aimed at the detection of hidden orebodies. this requirement will be greatly enhanced if there is any retardation in the introduction of fast reactors. (author)
International Uranium Resources Evaluation Project (IUREP) national favourability studies: Sri Lanka
International Nuclear Information System (INIS)
1977-10-01
Sri Lanka is essentially a detached portion of the Deccan Plateau of south India and like it, is underlain almost everywhere by hard old Precambrian rocks. Prior to 1940 there was no systematic organised geological survey work on the island. Between 1957 and 1962 a partial aerial survey and field traverses were conducted in a search for radio- active minerals. Since then a modest programme has continued. Thorianite was first discovered in placer deposits in 1903 and prospecting has found many other refractory radioactive minerals probably derived from the weathering of pegmatites. Monazite is found as an important constituent of beach placer deposits and it is estimated to have an average content of 8-10%ThO 2 and 0.3 - 0.5% U 3 O 8 . Up to 1000 tons monazite per year could be produced from the beach sand industry. Sri Lanka has had very little systematic exploration for uranium and as it is largely composed of Precambrian rocks it deserves closer attention. On the other hand it is part of a thorium rich province and there is a body of technical opinion that believes that thorium rich provinces are unlikely to contain significant uranium deposits. For these reasons it is estimated that the Speculative Potential may be within the range of 1000 to 10,000 tonnes uranium. In addition it maybe possible to produce up to 5 tonnes uranium and 100 tonnes thorium from the beach sand industry on an annual basis. (author)
Uranium concentration monitor manual, secondary intermediate evaporator
International Nuclear Information System (INIS)
Russo, P.A.; Sprinkle, J.K. Jr.; Slice, R.W.; Strittmatter, R.B.
1985-08-01
This manual describes the design, operation, and measurement control procedures for the automated uranium concentration monitor on the secondary intermediate evaporator at the Oak Ridge Y-12 Plant. The nonintrusive monitor provides a near-real time readout of uranium concentration in the return loop of time recirculating evaporator for purposes of process monitoring and control. A detector installed near the bottom of the return loop is used to acquire spectra of gamma rays from the evaporator solutions during operation. Pulse height analysis of each spectrum gives the information required to deduce the concentration of uranium in the evaporator solution in near-real time. The visual readout of concentration is updated at the end of every assay cycle. The readout includes an alphanumeric display of uranium concentration and an illuminated, colored LED (in an array of colored LEDs) indicating whether the measured concentration is within (or above or below) the desired range. An alphanumeric display of evaporator solution acid molarity is also available to the operator. 9 refs., 16 figs., 4 tabs
International Nuclear Information System (INIS)
Zhu Hongxun; Pan Hongping; Jian Xingxiang
2008-01-01
Prognosis and evaluation of uranium resources in Jiangzha region, Sichuan province are carried out through the multiple correlation analysis method. Through combining the characteristics of the methods and geology circumstance of areas to be predict, the uranium source, rock types, structure, terrain, hot springs and red basin are selected as estimation variable (factor). The original data of reference and predict unit are listed first, then correlation degree is calculated and uranium mineralization prospect areas are discriminated finally. The result shows that the method is credible, and should be applied to the whole Ruoergai uranium metallogenic area. (authors)
Environmental issues related to uranium mining
International Nuclear Information System (INIS)
Gorber, D.M.; Chambers, D.B.
1983-01-01
This paper introduces the environmental issues (both real and perceived) associated with uranium exploration, mining, milling, and tailings management. As well, some of the issues pertaining to the closeout of uranium tailings areas are discussed. These issues have received considerable attention in Canada in public inquiries and hearings that have been held across the country. The major conclusions of some of these hearings are also noted
Geohydrological investigation of an uranium anomaly near Vanzylsrus in the Northern Cape Province
International Nuclear Information System (INIS)
Levin, M.; Talma, A.S.; Vogel, J.C.
1982-01-01
An anomaly, caused by low-grade uranium accumulations in organic-rich diatomaceous earth deposits, was located by an airborne radiometric survey near Vanzylsrus in the Northern Cape. Low-grade uraniferous calcrete also occurs in the vicinity of the anomaly. A significant uranium anomaly was found along the whole course of the palaeodrainage with the highest values occuring behind a dolerite dyke a few kilometres south of the confluence. A multidisciplinary approach in corporating geohydrology, water geochemistry, isotopic data and radiometric borehole logging studies was used to evaluate its potential
Energy Technology Data Exchange (ETDEWEB)
Zakari, A.A.; Mima, S.; Bidaud, A.; Criqui, P.; Menanteau, P.; David, S.; Pagel, M.; Chagnes, A.; Cote, G.; Courtaud, B.; Thiry, J.; Miehe, J.M.; Gilbert, F.; Cuney, M.; Bruneton, P.; Ewington, D.; Vautrin-Ul, C.; Cannizzo, C.; Betelu, S.; Chausse, A.; Ly, J.; Bourgeois, D.; Maynadie, J.; Meyer, D.; Clavier, N.; Costin, D.T.; Cretaz, F.; Szenknect, S.; Ravaux, J.; Poinssot, C.; Dacheux, N.; Durupt, N.; Blanvillain, J.J.; Geffroy, F.; Aparicio, B.; Dubessy, J.; Nguyen-Trung, C.; Robert, P.; Uri, F.; Beaufort, D.; Lescuyer, J.L.; Morichon, E.; Allard, T.; Milesi, J.P.; Richard, A.; Rozsypal, C.; Mercadier, J.; Banks, D.A.; Boiron, M.C.; Cathelineau, M.; Dardel, J.; Billon, S.; Patrier, P.; Wattinne, A.; Vanderhaeghe, O.; Fabre, C.; Castillo, M.; Salvi, S.; Beziat, D.; Williams-Jones, A.E.; Trap, P.; Durand, C.; Goncalves, P.; Marquer, D.; Feybesse, J.L.; Richard, Y.; Orberger, B.; Hofmann, A.; Megneng, M.; Orberger, B.; Bouttemy, M.; Vigneron, J.; Etcheberry, A.; Perdicakis, M.; Prignon, N.; Toe, W.; Andre-Mayer, A.S.; Eglinger, A.; Jordaan, T.; Hocquet, S.; Ledru, P.; Selezneva, V.; Vendryes, G.; Lach, P.; Cuney, M.; Mercadier, J.; Brouand, M.; Duran, C.; Seydoux-Guillaume, A.M.; Bingen, B.; Parseval, P. de; Guillaume, D.; Bosse, V.; Paquette, J.L.; Ingrin, J.; Montel, J.M.; Giot, R.; Maucotel, F.; Hubert, S.; Gautheron, C.; Tassan-Got, L.; Pagel, M.; Barbarand, J.; Cuney, M.; Lach, P.; Bonhoure, J.; Leisen, M.; Kister, P.; Salaun, A.; Villemant, B.; Gerard, M.; Komorowski, J.C.; Michel, A.; Riegler, T.; Tartese, R.; Boulvais, P.; Poujols, M.; Gloaguen, E.; Mazzanti, M.; Mougel, V.; Nocton, G.; Biswas, B.; Pecaut, J.; Othmane, G.; Menguy, N.; Vercouter, T.; Morin, G.; Galoisy, L.; Calas, G.; Fayek, M.
2010-11-15
This document brings together the abstracts of the 39 presentations given at this meeting days on uranium, organized by the French geological society, and dealing with: 1 - Prospective study of the electronuclear technological transition; 2 - The front-end of the nuclear cycle: from the molecule to the process; 3 - Geophysics: recent changes; 4 - Use of well logging in uranium exploration; 5 - Genetical classification of thorium deposits; 6 - Genetical nomenclature of uranium sources; 7 - Uranium deposits linked to a Proterozoic discordance - retrospective; 8 - The use of spectral analysis techniques in uranium exploration: real-time mapping of clay alteration features; 9 - Development of functionalized silk-screened carbon electrodes for the analysis of uranium trace amounts; 10 - Study of the actinides solvation sphere in organic environment; 11 - Thermodynamic of uraniferous phases of interest for the nuclear cycle; 12 - Heap leaching of marginal minerals at Somair: from lab studies to the production of 700 t of uranium/year; 13 - Agglomeration phenomenology and role of iron in uranium heap leaching; 14 - Chloride uranyl complexes up to 300 deg. C along the saturation vapour curve: Raman spectroscopy analysis and metallogenic consequences; 15 - Weathering systems in the Shea Creek deposit (Athabasca, Canada): vertical variability of argillaceous weathering; 16 - Weathering systems in the Shea Creek deposit (Athabasca, Canada): contribution of irradiation defects in clays to the tracing of past uranium migrations; 17 - Uranium concentrations in mineralizing fluids of the Athabasca basin: analytical and experimental approach; 18 - Paleo-surfaces and metallic rooting: the autochthonous uranium of pre-Athabasca paleo-alterites, Canada; 19 - Distribution of argillaceous parageneses in the Imouraren deposit - Niger; 20 - Heat flux and radioelements concentration (U, Th, K) of precambrian basements: implications in terms of crust growth mechanisms, paleo
Corporate citizenship and the Saskatchewan uranium industry
International Nuclear Information System (INIS)
Michel, B.M.
1995-01-01
Saskatchewan has vast and rich uranium deposits which in 1994 contributed almost 30% to world uranium production. There are only two mining operators in the province which is subject to the overlapping jurisdictions of the provincial and federal governments. The sparse population consists of two distinct groups, a minority population of people of native ancestry in the north and people typical of most North American rural communities living in the south. Each has its own concerns and expectations with respect to the mining operations and nuclear power. The comprehensive community relations programme set up by the mining industry against this background is described. It includes trying to address concerns, offering training, employment and business opportunities, and supporting the social and cultural aspects of community life. (UK)
Assessment on ecological environment impact caused by the exploitation of a uranium mine
International Nuclear Information System (INIS)
Zhang Xueli; Xu Lechang; Li Xianjie; Wang Erqi; Wei Guangzhi; Hu Penghua
2008-01-01
On the basis of investigation, the assessment index of ecological environment impact is determined from the aspects of natural eco-environment and social eco-environment. Both qualitative analysis and quantitative assessment are adopted for assessing the ecological environment impact during the exploitation of a uranium mine in Jiangxi province. The results show that some values of the assessment index in natural eco-subsystem decline slightly, while those of the assessment index in social eco-subsystem ascend so that the ecological environment quality around the uranium mine ascend slightly. Moreover, some reasonable advices on eco-environment protection measures are put forward in order to build a ecotype uranium mine. (authors)
Orientation geochemical survey for uranium exploration using 230Th
International Nuclear Information System (INIS)
Xia Dingliang.
1985-01-01
The distribution of 230 Th in soils, rocks and ores and its relationship with respect to uranium ore formation are discussed for its possible use in geochemical exploration for U. 230 Th, U and Ra, being members of the same decay series, are different in their geochemical behavior upon which the study is orientated. Twenty uranium deposits and occurrences located in western and southern Hunan province are tested. Geochemical data obtained are comprehensively correlated. It is suggested that 230 Th is useful not only in U-Ra disequilibrium study but also in understanding the geochemical evolution of U ores. The data aid to interpret the genesis of uranium deposits and to assess the radioactive anomalies and uranium-bearing zones. Therefore, it can be adopted as a tool for searching in deep-buried uranium ores. The field procedure is rather simple and flexible to meet any geological environment. It is easy to read out and is less influnced by any kind of interference. In case of disequilibrium caused by oxidation and reduction during the period of ore formation it still gives good indication compared with that of radiometry, radonmetry and geochemical sampling for U
A new approach for geochemical surveys of large areas for uranium resource potential
International Nuclear Information System (INIS)
Arendt, J.W.; Butz, T.R.; Cagle, G.W.; Kane, V.E.; Nichols, C.E.
1977-01-01
The Grand Junction, Colorado office of the United States Energy Research and Development Administration (ERDA) is conducting the National Uranium Resource Evaluation Program to evaluate the uranium resources in the United States and Alaska. The program is designed to identify favorable areas for uranium exploration, to assess the supply of domestic resources, and to improve exploration technology. The Nuclear Division of the Union Carbide Corporation has been assigned the responsibility of conducting a hydrogeochemical and stream sediment survey of the mid-continental states in the United States. This survey covers approximately 2,500,000 km 2 (1,000,000 mi 2 ) and includes the states of Texas, Oklahoma, Kansas, Nebraska, South Dakota, North Dakota, Minnesota, Wisconsin, Michigan, Indiana, Illinois, and Iowa. The uranium potential of sandstones, Precambrian conglomerates, veins, granites, and phosphorites is being assessed utliizing a three-part program consisting of pilot surveys in each geological province and two phases of reconnaissance sampling of drainage basins. Samples of stream sediment, stream water, groundwater, algae, and vegetation are analyzed for uranium and some 20 additional elements. Data resulting from this program is released to private industry by ERDA as it becomes available. Analysis of results from a typical three-part survey are given. For distinctive geological regions, the pilot survey will: (1) define characteristic concentration background levels of the elements of interest, (2) identify potential uranium pathfinder elements, (3) determine relationship between stream, stream sediment and botanical samples, (4) identify any necessary modification to field sampling techniques, and (5) determine necessary sensitivities required for chemical analysis. The first reconnaissance phase average sample spacing of one station per 250 km 2 (100 mi 2 ) drainage basin is shown to delineate general boundaries of uranium provinces, and the second
International Nuclear Information System (INIS)
Gorustovich, S.; Guidi, F.; Bárbaro, N.; Nievas, H.; Tomellini, G.
2013-01-01
Results of geological and environmental observations made by professionals of the Comisión Nacional de Energía Atómica (CNEA) down streams Don Otto uranium mine on the Sunchales creek, from Los Guanacos strait down to the Tonco river mouth, and from river mouth down to narrow pass named Salto Grande, are presented in this report. La Yesera, Las Curtiembres and Los Blanquitos Formations of the Pirgua Subgroup, and Lecho and Yacoraite Formations of the Balbuena Subgroup crops out in that area (Salta Group, Cretaceous- Middle Eocene). Water stream analyses have given uranium contents between 890 μg/L and 1,100 μg/L, and uranium in stream sediments between 4 μg/g and 14 μg/g; radimetric anomalias up to 1,500 c/s in discoloured facies of the Las Curtiembres Formation, and 2,000 c/s in dark pelitic sediments of the Yacoraite Formation. A new zone with uranium traces in Curtiembres Formation belonging to the Pirgua Subgroup has been identified in the Alemanía cretaceous basin, which is stratigraphically similar to Cajoncillo, Las Abritas and El Fraile deposits. Those traces in addition to the other ones localized in the upper third of the Yacoraite Formation would have been originated by the geochemical uranium anomalies in waters and stream sediments by uranium leaching of rocks. The geochemical uranium anomalies in water and sediments are not a consequence of the antropic activity of the uranium mining carried out in Don Otto mine (1961-1982). (authors) [es
A study of radioactive elements of various rocks in Pattani Province with gamma ray spectrometer
Directory of Open Access Journals (Sweden)
Kaewtubtim, P.
2002-01-01
Full Text Available The radioactivity of the three elements, potassium, uranium and thorium, in rocks of various types in Pattani Province was investigated by using a gamma ray spectrometer. It was found that potassium contents in igneous rocks, sedimentary rocks and metamorphic rocks were 6.29 %, 2.21% and 1.54 % respectively. Uranium equivalent contents in igneous rock, sedimentary rocks and metamorphic rocks were found to be 22.51 ppm, 11.25 ppm and 14.13 ppm, while thorium contents in these rocks were 21.78 ppm, 18.88 ppm and 18.15 ppm respectively. The results obtained were similar to those reported by Pungtip Ranglek (1995 for igneous rock at Liwong Pluton site in Thepha, Na Thawi, Chana and Saba Yoi Districts, Songkhla Province, and were about six times higher than those reported by Kittichai Wattananikorn (1994 for igneous rock in the northern part of Thailand.
International Nuclear Information System (INIS)
Cassinis, G.; Dal Piaz, G.V.; Massari, P.F.
1986-01-01
Detailed structural and sedimentological studies have been conducted in two areas near the Val Vedello uranium mine in northern Italy. These studies indicate that both the Variscan basement (locally called the Orobic basement) and the Permian cover rocks were thrust southward during the Alpine orogeny. Variscan mylonitic zones were rejuvenated during the Alpine orogeny and became fault boundaries for the Permo-Triassic basins. Alpine faults also are related to contemporaneous east-west folds and these faults have displaced Permo-Triassic uranium deposits. Uranium mineralisation is attributed to a Late Permian to Triassic geothermal event which leached uranium from Permian ignimbrites and transported it along Permo-Triassic faults. Detailed mapping indicates that the host sediments formed in an arid, closed basin characterised by alluvial fans and perennial saline lakes. (orig.)
International Nuclear Information System (INIS)
Kleinman, L.E.; Maloberti, A.L.; Gayone, M.R.; Kaufmann, C.; Sruoga, P.
2013-01-01
Radiometric surveys are a rapid tool to measure uranium (U), thorium (Th) and potassium (K) concentrations in rocks and are very useful in the exploration for radioactive minerals. The distribution of uranium in Jurassic volcanic rocks of the province of Santa Cruz is evaluated in this work using ground gamma-ray spectrometry and rock geochemistry in order to assess its potential to form uranium deposits. Five areas were selected, which had some previous data of high radiometric values and detailed geological information. Measurements were carried out with a portable gamma-ray spectrometer (Exploranium-GR 320®) in andesites, ignimbrites, rhyolites, silicified areas, ash-fall tuffs and lacustrine sediments corresponding to the Bahía Laura and to El Quemado complexes. The results were similar in the five surveyed areas: radiometric concentrations show good positive correlations with chemical composition of the studied rocks for both K and Th, and a relatively poorer correlation for U. Different processes such as magmatic differentiation, vapor phase crystallization, hydrothermal alteration and supergene alteration are reflected in the distribution of these elements. U concentrations increase in the more glassy rocks, in areas with hydrothermal silicification, and in fracture zones, features that should be considered in future surveys. The calkalkaline composition and arc-signatures of the Jurassic magmatism are not the most favorable for uranium enrichment and for concentration of significant mineralizations. However, the extensional tectonic setting; the occurrence of calderas with facies slightly enriched in U and Th, in addition to hydrothermal activity are positive factors for U exploration. (authors) [es
Low grade uranium deposits of India - a bane or boon
International Nuclear Information System (INIS)
Chaki, Anjan
2010-01-01
Uranium resources of the world is estimated to be 5.5 million tonnes and the proven resources in India forms 3% of the world resources. The biggest uranium deposit is the Olympic dam deposit in Australia, which contains nearly one million tonnes of 0.04% U 3 O 8 , while the highest grade of nearly 20% is established in the McArthur river deposit, Canada. Another very high grade deposit, the Cigar lake deposit, is established in Canada with an average grade of nearly 18%. Most of the uranium deposits established in India so far falls under the category of low grade. These low grade uranium deposits are distributed mainly in Singhbhum Shear Zone, eastern India; in parts of Chhattisgarh; Southern parts of Meghalaya; Cuddapah Basin, Andhra Pradesh; in parts of Karnataka and Aravalli- and Delhi Supergroups, Rajasthan and Haryana. These deposits are mainly hydrothermal vein type, stratabound type and unconformity related. The Singhbhum Shear Zone, Jharkhand hosts a seventeen low grade uranium deposits, aggregating about 30% of Indian uranium resources. The uranium mineralisation hosted by Vempalle dolostone extends over 160 km belt along southwestern margin of Cuddapah Basin in Andhra Pradesh and accounts 23% of the Indian resources. Though the dolostone hosted Tummalapalle uranium deposit was established in the early nineties, because of techno-economic constraints, the deposit remained dormant. As a consequence of the development of an innovative pressure alkali beneficiation process, the deposit became economically viable and a mine and mill are being constructed here. Recent exploration inputs are leading to prove a number of low grade uranium deposits in the extension areas of Tummalapalle. Nearly 10 blocks have been identified within a 30 km belt which are being actively explored and a large uranium deposit has already been proved in this province. The deposit at Tummalapalle and adjoining areas is likely to become the second biggest deposit in the world. The
International Nuclear Information System (INIS)
Butt, C.R.M.; Mann, A.W.; Horwitz, R.C.
1984-01-01
Surficial uranium deposits in Western Australia are largely in the Yilgarn Block in areas of Archean granitoids and greenstones, and in the Gascoyne Province in Proterozoic granites and gneisses. The region has had a long weathering history marked by continuous planation developing a regolith up to 100 metres thick. The distribution of calcrete type uranium deposits is controlled by geologic as well as weathering, erosion and climatic factors. Valley, playa and terrace deposits are recognized. The principal known surficial uranium deposit, Yeelirrie, occurs in the Yilgarn block as a valley deposit. (author)
Features of geology in Anyuan hot spot area of southern Jiangxi Province
International Nuclear Information System (INIS)
Lin Jinrong; Li Ziying; Pang Yaqing; Hu Zhihua; Gao Fei; Wang Yongjian; Zhong Qilong
2013-01-01
Based on the synthetical research on the characteristics of regional geology and structure, magmatic activity and metamorphism, it is considered that Anyuan area in southern Jiangxi Province has features of continent hot spot, and Anyuan hot spot area is an integrated geology body effected by the metamorphism. magmatism, tectonism and hydrothermal metallogenesis originated by the mantle upheaving. Anyuan hot spot area is a mineralization cluster area of uranium and poly-metal, which has the feature of ring structure, negative abnormity of gravity and high field of radioactivity. It is considered that metallogenesis of uranium and poly-metal is close to crust-mantle mixing and fluid of deep source. (authors)
Quantitative determination of uranium by SIMS
International Nuclear Information System (INIS)
Kuruc, J.; Harvan, D.; Galanda, D.; Matel, L.; Aranyosiova, M.; Velic, D.
2008-01-01
The paper presents results of quantitative measurements of uranium-238 by secondary ion mass spectrometry (SIMS) with using alpha spectrometry as well as complementary technique. Samples with specific activity of uranium-238 were prepared by electrodeposition from aqueous solution of UO 2 (NO 3 ) 2 ·6H 2 O. We tried to apply SIMS to quantitative analysis and search for correlation between intensity obtained from SIMS and activity of uranium-238 in dependence on the surface's weight and possibility of using SIMS in quantitative analysis of environmental samples. The obtained results and correlations as well as results of two real samples measurements are presented in this paper. (authors)
Uranium concentration monitor manual: 2300 system
International Nuclear Information System (INIS)
Russo, P.A.; Sprinkle, J.K. Jr.; Stephens, M.M.
1985-04-01
This manual describes the design, operation, and procedures for measurement control for the automated uranium concentration monitor on the 2300 solvent extraction system at the Oak Ridge Y-12 Plant. The nonintrusive monitor provides a near-real time readout of uranium concentration at two locations simultaneously in the solvent extraction system for process monitoring and control. Detectors installed at the top of the extraction column and at the bottom of the backwash column acquire spectra of gamma rays from the solvent extraction solutions in the columns. Pulse-height analysis of these spectra gives the concentration of uranium in the organic product of the extraction column and in the aqueous product of the solvent extraction system. The visual readouts of concentrations for process monitoring are updated every 2 min for both detection systems. Simultaneously, the concentration results are shipped to a remote computer that has been installed by Y-12 to demonstrate automatic control of the solvent extraction system based on input of near-real time process operation information. 8 refs., 13 figs., 4 tabs
International Nuclear Information System (INIS)
Maruejol, P.; Cuney, M.; Poty, B.; Neto, A.M.
1987-01-01
In the central zone of the Sao Francisco Craton (South Bahia), the lower Proterozoic Lagoa Real granites and orthogneisses overthrust to the West the younger Urandi and Espinhaco metamorphic series, probably a late Brazilian event. This thrust is related to the regional metamorphism (amphibolite facies) of the Lagoa Real granites and induces a reverse HP metamorphism in the over thrusted series. Undeformed granites (sao Timoeto type) present two feldspars, perthitic orthoclase largely predominant over plagioclase (oligoclase ≥ albite), blue quartz, Fe-rich amphibole and biotite ± clinopyroxene assemblages, ilmenite ≥ magnetite, zircon, apatite, allanite and Nb ± Ti-REE oxides and silicates. The crystallization of the granites begins at high temperature and under low fO 2 and P H2O conditions. Fractional crystallization of pyroxene and plagioclase leads to silica enrichment during magmatic differentiation. Increasing fO 2 and P H2O are observed during this evolution. Orthogneisses show strongly recrystallized paragenesis: equal abundance of non-perthitic microcline and plagioclase (oligoclase ≤ albite), quartz, more Al-rich amphibole and biotite, magnetite, sphene, zircon, allanite, Nb ± Ti-REE oxides and silicates, and ± apatite. HT Na and Ca metasomatism occurs 330 Ma later than granite emplacement and is synchronous with important uranium mineralizations. Major elements and trace-elements geochemistry of the granites and orthogneisses indicate subalkaline to alkaline typology. Incompatible behaviour of Th, REE, Y, Zr, Nb, and F points out a convergence with alkaline magmatism. CI, F, Th, Y, REE, NB enrichments and Ba, Sr depletions are also related to a late magmatic stage. U-Th-rich and metamict accessory minerals of the granites represent a favorabl source for the Lagoa Real uranium ore-deposits [pt
Uranium deposit of Bauzot (Saone et Loire); Le gisement d'uranium de Bauzot (Saone et Loire)
Energy Technology Data Exchange (ETDEWEB)
Carrat, G H [Commissariat a l' Energie Atomique, Saone et Loire (France). Centre d' Etudes Nucleaires
1956-07-01
The best known of the uranium ore deposits of the Morvan (a province of France) is in the form of a bundle of quartz-fluor lodes with pitchblende and B.P.G.C. ore. The pitchblende seems to have been deposited at different time in respect to the formation of the gangue minerals, but generally it is ore of the first-formed. The main concentrations of ore are always in the vicinity of dykes of basic crystalline rocks. (author) [French] Bauzot, le plus connu des gisements d'uranium du Morvan est constitue d'un faisceau de filons quartzofluores, mineralise en pechblende et sulfures B.P.G.S. La pechblende semble s'etre mide en place a des periodes variables par rapport a la gangue mais en general elle constitue un des premiers mineraux deposes. Les principaux amas se situent toujours a proximite de filons de roches lamprophyriques. (auteur)
National Uranium Resource Evaluation: Marfa Quadrangle, Texas
International Nuclear Information System (INIS)
Henry, C.D.; Duex, T.W.; Wilbert, W.P.
1982-09-01
The uranium favorability of the Marfa 1 0 by 2 0 Quadrangle, Texas, was evaluated in accordance with criteria established for the National Uranium Resource Evaluation. Surface and subsurface studies, to a 1500 m (5000 ft) depth, and chemical, petrologic, hydrogeochemical, and airborne radiometric data were employed. The entire quadrangle is in the Basin and Range Province and is characterized by Tertiary silicic volcanic rocks overlying mainly Cretaceous carbonate rocks and sandstones. Strand-plain sandstones of the Upper Cretaceous San Carlos Formation and El Picacho Formation possess many favorable characteristics and are tentatively judged as favorable for sandstone-type deposits. The Tertiary Buckshot Ignimbrite contains uranium mineralization at the Mammoth Mine. This deposit may be an example of the hydroauthigenic class; alternatively, it may have formed by reduction of uranium-bearing ground water produced during diagenesis of tuffaceous sediments of the Vieja Group. Although the presence of the deposit indicates favorability, the uncertainty in the process that formed the mineralization makes delineation of a favorable environment or area difficult. The Allen intrusions are favorable for authigenic deposits. Basin fill in several bolsons possesses characteristics that suggest favorability but which are classified as unevaluated because of insufficient data. All Precambrian, Paleozoic, other Mesozoic, and other Cenozoic environments are unfavorable
Different periods of uranium and thorium occurrence in Madagascar (1960)
International Nuclear Information System (INIS)
Moreau, M.
1960-01-01
In Madagascar, the first typical occurrences of thorium and uranium are about 500 million years old. Previously thorium and uranium were rather concentrated in the granitic and charnockitic zones, chiefly in minerals such as monazite, apatite and zircon. At the end of the Precambrian period, metasomatic granites occur especially in the anticlinal series (Andriba orthite granite). The granitization is followed by the formation of the main pegmatitic areas in the Island with Th-U niobotantalates, uraninite and beryl. The pegmatites are well developed in the synclinal series with a poor migmatization or no migmatization at all. In the same time a large uranium and thorium province with uranothorianite deposits appears within the calcomagnesian series of the Southern part of Madagascar. Later, large amounts of monazite were carried down to the detritic Karroo sediments during tile erosion of the metamorphic precambrian rocks. Monazite has been concentrated again by frequent marine incursions, till the present time. In the medium Karroo, near Folakara, uranium minerals occur in direct relation with carbonaceous material. Finally we must note the uranium occurrence in the pleistocene carbonaceous shales of Antsirabe basin, in contact with crystalline rocks. (author) [fr
Uranium geology of the eastern Baker Lake basin, District of Keewatin, Northwest Territories
International Nuclear Information System (INIS)
Miller, A.R.
1980-01-01
Proterozoic sequences associated with major unconformities are potential uranium metallogenic provinces. Late Aphebian to Paleohelikian Dubawnt Group contintental clastic sedimentary and subaerial alkaline volcanic rocks and underlying Archean gneisses, District of Keewatin, Northwest Territories, represent one such uraniferous metallogenic province. Three types of uranium mineralization are present in the eastern Baker Lake basin, which extends from Christopher Island at the eastern end of Baker Lake southwestwards to the western limit of Thirty Mile Lake. The three uranium associations are: 1) fracture controlled mineralization in the Dubawnt Group and basement gneisses (U-Cu-Ag-Au-Se or U-Cu-Pb-Mo-Zn), 2)diatreme breccia mineralization in basement gneisses (U-Cu-Zn), and 3) impregnation and microfracture mineralization in altered arkose peripheral to lamprophyre dykes(U-Cu-Ag). Hydrothermal fracture related mineralization is controlled by northwest- and east-northeast-trending fault-fracture zones. Diatreme breccia mineralization results from the channelling of groundwaters through highly permeable brecciated gneiss. Mineralization within the altered Kazan arkose peripheral to alkaline dyke complexes formed by a two stage process. Iron and copper sulphides and silver were deposited within the outer portions of the thermal aureole in response to a temperature and Eh gradient across a convective cell created by the thermal anomaly of the dyke complex. The epigenetic sulphide mineralization subsequently provided the reducing environment for precipitation of uranium from groundwater. All three uranium associations show a close spatial distribution to the basal Dubawnt unconformity. The lithological and structural relationships of the Dubawnt Group rocks, types of mineralization and associated alteration assemblages are strikingly similar to the Beaverlodge district, Saskatchewan. (author)
International Nuclear Information System (INIS)
Yang Shanghai
2011-01-01
Located in the middle part of Jiuyishan complex pluton, Nanling metallogenic belt, Dawan uranium ore field in Hunan Province is an important uranium-producing and rare metal, nonferrous metal cluster area due to the favourable mineralization environment. The Cambrian is the main uranium source bed and their contact zone to the pluton is the favorable part for mineralization. The uranium deposits which have been explored are all located in the exocontact zone of Jinjiling pluton in the middle part of Jiuyishan complex pluton which is composed of the independent eastern and western magma evolution centers. In the west center, Jinjiling pluton is closely related to uranium mineralization where the trinity geologic setting was formed with magma evolution, hydrothermal fluid action and mineralization. The deep slitted and large faults provide the pathway and thermodynamic source for circulating migration of mineralizing fluid. The uranium mineralization mainly occurred in crustal stress conversion period of Late Cretaceous and related to the tensive NW extending fault and deep originated fluid. The gravity, aero magnetic, airborne gamma-ray spectrometry anomalies and radioactivity hydrochemical anomaly are important criteria for uranium prospecting. Based on the analysis of regional uranium mineralization environment, the prospecting potential is forecasted. (authors)
International Nuclear Information System (INIS)
Zakari, A.A.; Mima, S.; Bidaud, A.; Criqui, P.; Menanteau, P.; David, S.; Pagel, M.; Chagnes, A.; Cote, G.; Courtaud, B.; Thiry, J.; Miehe, J.M.; Gilbert, F.; Cuney, M.; Bruneton, P.; Ewington, D.; Vautrin-Ul, C.; Cannizzo, C.; Betelu, S.; Chausse, A.; Ly, J.; Bourgeois, D.; Maynadie, J.; Meyer, D.; Clavier, N.; Costin, D.T.; Cretaz, F.; Szenknect, S.; Ravaux, J.; Poinssot, C.; Dacheux, N.; Durupt, N.; Blanvillain, J.J.; Geffroy, F.; Aparicio, B.; Dubessy, J.; Nguyen-Trung, C.; Robert, P.; Uri, F.; Beaufort, D.; Lescuyer, J.L.; Morichon, E.; Allard, T.; Milesi, J.P.; Richard, A.; Rozsypal, C.; Mercadier, J.; Banks, D.A.; Boiron, M.C.; Cathelineau, M.; Dardel, J.; Billon, S.; Patrier, P.; Wattinne, A.; Vanderhaeghe, O.; Fabre, C.; Castillo, M.; Salvi, S.; Beziat, D.; Williams-Jones, A.E.; Trap, P.; Durand, C.; Goncalves, P.; Marquer, D.; Feybesse, J.L.; Richard, Y.; Orberger, B.; Hofmann, A.; Megneng, M.; Orberger, B.; Bouttemy, M.; Vigneron, J.; Etcheberry, A.; Perdicakis, M.; Prignon, N.; Toe, W.; Andre-Mayer, A.S.; Eglinger, A.; Jordaan, T.; Hocquet, S.; Ledru, P.; Selezneva, V.; Vendryes, G.; Lach, P.; Cuney, M.; Mercadier, J.; Brouand, M.; Duran, C.; Seydoux-Guillaume, A.M.; Bingen, B.; Parseval, P. de; Guillaume, D.; Bosse, V.; Paquette, J.L.; Ingrin, J.; Montel, J.M.; Giot, R.; Maucotel, F.; Hubert, S.; Gautheron, C.; Tassan-Got, L.; Pagel, M.; Barbarand, J.; Cuney, M.; Lach, P.; Bonhoure, J.; Leisen, M.; Kister, P.; Salaun, A.; Villemant, B.; Gerard, M.; Komorowski, J.C.; Michel, A.; Riegler, T.; Tartese, R.; Boulvais, P.; Poujols, M.; Gloaguen, E.; Mazzanti, M.; Mougel, V.; Nocton, G.; Biswas, B.; Pecaut, J.; Othmane, G.; Menguy, N.; Vercouter, T.; Morin, G.; Galoisy, L.; Calas, G.; Fayek, M.
2010-11-01
This document brings together the abstracts of the 39 presentations given at this meeting days on uranium, organized by the French geological society, and dealing with: 1 - Prospective study of the electronuclear technological transition; 2 - The front-end of the nuclear cycle: from the molecule to the process; 3 - Geophysics: recent changes; 4 - Use of well logging in uranium exploration; 5 - Genetical classification of thorium deposits; 6 - Genetical nomenclature of uranium sources; 7 - Uranium deposits linked to a Proterozoic discordance - retrospective; 8 - The use of spectral analysis techniques in uranium exploration: real-time mapping of clay alteration features; 9 - Development of functionalized silk-screened carbon electrodes for the analysis of uranium trace amounts; 10 - Study of the actinides solvation sphere in organic environment; 11 - Thermodynamic of uraniferous phases of interest for the nuclear cycle; 12 - Heap leaching of marginal minerals at Somair: from lab studies to the production of 700 t of uranium/year; 13 - Agglomeration phenomenology and role of iron in uranium heap leaching; 14 - Chloride uranyl complexes up to 300 deg. C along the saturation vapour curve: Raman spectroscopy analysis and metallogenic consequences; 15 - Weathering systems in the Shea Creek deposit (Athabasca, Canada): vertical variability of argillaceous weathering; 16 - Weathering systems in the Shea Creek deposit (Athabasca, Canada): contribution of irradiation defects in clays to the tracing of past uranium migrations; 17 - Uranium concentrations in mineralizing fluids of the Athabasca basin: analytical and experimental approach; 18 - Paleo-surfaces and metallic rooting: the autochthonous uranium of pre-Athabasca paleo-alterites, Canada; 19 - Distribution of argillaceous parageneses in the Imouraren deposit - Niger; 20 - Heat flux and radioelements concentration (U, Th, K) of precambrian basements: implications in terms of crust growth mechanisms, paleo
Final Technical Report - In-line Uranium Immunosensor
International Nuclear Information System (INIS)
Blake, Diane A.
2006-01-01
In this project, personnel at Tulane University and Sapidyne Instruments Inc. developed an in-line uranium immunosensor that could be used to determine the efficacy of specific in situ biostimulation approaches. This sensor was designed to operate autonomously over relatively long periods of time (2-10 days) and was able to provide near real-time data about uranium immobilization in the absence of personnel at the site of the biostimulation experiments. An alpha prototype of the in-line immmunosensor was delivered from Sapidyne Instruments to Tulane University in December of 2002 and a beta prototype was delivered in November of 2003. The beta prototype of this instrument (now available commercially from Sapidyne Instruments) was programmed to autonomously dilute standard uranium to final concentrations of 2.5 to 100 nM (0.6 to 24 ppb) in buffer containing a fluorescently labeled anti-uranium antibody and the uranium chelator, 2,9-dicarboxyl-1,10-phenanthroline. The assay limit of detection for hexavalent uranium was 5.8 nM or 1.38 ppb. This limit of detection is well below the drinking water standard of 30 ppb recently promulgated by the EPA. The assay showed excellent precision; the coefficients of variation (CV's) in the linear range of the assay were less than 5% and CV?s never rose above 14%. Analytical recovery in the immunosensors-based assay was assessed by adding variable known quantities of uranium to purified water samples. A quantitative recovery (93.75% - 108.17%) was obtained for sample with concentrations from 7.5 to 20 nM (2-4.75 ppb). In August of 2005 the sensor was transported to Oak Ridge National Laboratory, for testing of water samples at the Criddle test site (see Wu et al., Environ. Sci. Technol. 40:3978-3985 2006 for a description of this site). In this first on-site test, the in-line sensor was able to accurately detect changes in the concentrations of uranium in effluent samples from this site. Although the absolute values for the uranium
Prospects for the uranium industry in Australia
International Nuclear Information System (INIS)
1976-02-01
The report covers the basic issues of the coming uranium era discussing the world supply and demand situation, the trend in uranium prices and the continuing move to nuclear power as the world's primary source of electrical energy. In Australia, unknowns such as future contract prices and quantities, production start dates, royalties and the outcome of the environmental inquiry create the speculative image of the uranium stocks. The first section of the report discusses the technical aspects of the nuclear industry but is necessarily brief because the real story is the world trend to nuclear power for economic and political reasons and the old story of supply and demand (discussed in section two). Within Australia some companies are better placed than others to benefit from the uranium era. Section three looks at prices and section four reviews the individual companies involved in the uranium industry in Australia. (author)
Prospects for the uranium industry in Australia
Energy Technology Data Exchange (ETDEWEB)
1976-02-01
The report covers the basic issues of the coming uranium era discussing the world supply and demand situation, the trend in uranium prices and the continuing move to nuclear power as the world's primary source of electrical energy. In Australia, unknowns such as future contract prices and quantities, production start dates, royalties and the outcome of the environmental inquiry create the speculative image of the uranium stocks. The first section of the report discusses the technical aspects of the nuclear industry but is necessarily brief because the real story is the world trend to nuclear power for economic and political reasons and the old story of supply and demand (discussed in section two). Within Australia some companies are better placed than others to benefit from the uranium era. Section three looks at prices and section four reviews the individual companies involved in the uranium industry in Australia.
International Nuclear Information System (INIS)
Xuan Yanxiu; Zhang Jielin
2010-01-01
Based on the spectrum characteristics analysis of uranium mineralization alteration rocks and minerals, and using satellite multi-spectral remote sensing image data as the main information sources, multiple remote sensing data processing techniques and methods such as color compound, band ratio, principal component analysis and image color segmentation, are synthetically applied to extract uranium mineralization and alteration information from the remote sensing image. The results of this study provided basic data for analysis of uranium ore-formation conditions in the area. (authors)
Potential uranium host rocks and structures in the central Great Plains
International Nuclear Information System (INIS)
Zeller, E.J.; Dreschhoff, G.; Angino, E.; Holdoway, K.; Hakes, W.; Jayaprakash, G.; Crisler, K.; Saunders, D.F.
1975-01-01
A preliminary study was completed of the uranium potential of the Central Great Plains. The study area extends from longitude 99 to 104 0 W and is bounded by the North Platte River on the north and the Canadian River on the south. This region has no known commercial uranium accumulations, but is an area which contains formations with similar facies that are known to have deposits in other areas. A new method of utilizing petroleum exploration gamma-ray well log data was tested in the western Kansas portion of the survey area. Gamma activities in the Dakota and Morrison formations were computer-processed by trend surface analysis, statistically analyzed, and the anomalies were compared with regional geomorphic lineaments derived from satellite imagery as well as regional geology, to draw conclusions as to their origin and significance. Conclusions are: (1) possible uraniferous provinces have been outlined in the subsurface of western Kansas; (2) the new well log data approach can be used to define potential uraniferous provinces in any well-explored petroleum region; (3) the close spatial correlation between anomalies and regional geomorphic lineaments provides strong support for the concept that the lineaments represent vertical fracture zones which can act as preferred pathways for vertical fluid migration; and (4) the location of the strongest anomalies over impervious salt bodies indicates that any uranium bearing mineralizers must have moved down through the geologic section rather than upward. Recommendations are made to extend the application of the well-log approach, to do drilling and sampling to prove whether the anomalies are really due to uranium, and to add geobotanical and emanometric measurements during future studies
Genetic aspects of uranium mineralization in the Himalaya
International Nuclear Information System (INIS)
Saraswat, A.C.; Mahadevan, T.M.
1989-01-01
The Himalayan Uranium Province hosts five major types of uranium mineralization: (1) stratiform remobilized (Proterozoic), (2) structurally controlled hydrothermal (Proterozoic), (3) black shale-phosphorite (Palaeozoic-Mesozoic), (4) sandstone (Siwalik belt, Tertiary), and (5) primary disseminations in granitoids (Tertiary). Evaluation of the genetic aspects of these types has led to the identification of distinct spatial (lithostratigraphic and tectonic units) and temporal relations among them. The sandstone types are confined to the Tertiary (Middle Miocene to Pleistocene) molasse formations found south of th Main Boundary Thrust (MBT). Between the MBT and the Main Central Thrust, in the Lesser Himalaya, mineralization hosted in the Chail quartzite-phyllite ± metabasic sequences is of stratiform remobilized type. The structurally controlled hydrothermal type is confined to Dalings and gneisses. Syngenetic uranium in black shale-phosphorite sequences of Palaeozoic-Mesozoic age is found on the southern fringes of the Lesser Himalaya, bordering the MBT. Disseminated uranium occurs in the Tertiary and Proterozoic(?) granitoids of the Greater Himalaya and Ladakh. Rb-Sr geochronological data on host rocks and U-Pb dates on uraninites from some areas indicate that uranium mineralization in stratiform remobilized and structurally controlled types hosted by the Chails, Dalings and gneisses is essentially Precambrian and thus existed much before the Himalayan Orogeny. The Himalayan Orogeny, however, appears to have aided in further remobilization. The sandstone type mineralization in the Siwalik, on the other hand, is directly related to the process of formation of the foredeep and molasse sedimentation and subsequent uplift and epigenesis of the uranium mineralization, all of which are directly relatable to the evolution of the Himalaya. The relevance of deep seated lineament structures to mineralization, particularly of uranium, needs to be evaluated critically, as most
(238)U and total radioactivity in drinking waters in Van province, Turkey.
Selçuk Zorer, Özlem; Dağ, Beşir
2014-06-01
As part of the national survey to evaluate natural radioactivity in the environment, concentration levels of total radioactivity and natural uranium have been analysed in drinking water samples. A survey to study natural radioactivity in drinking waters was carried out in the Van province, East Turkey. Twenty-three samples of drinking water were collected in the Van province and analysed for total α, total β and (238)U activity. The total α and total β activities were counted by using the α/β counter of the multi-detector low background system (PIC MPC-9604), and the (238)U concentrations were determined by inductively coupled plasma-mass spectrometry (Thermo Scientific Element 2). The samples were categorised according to origin: tap, spring or mineral supply. The activity concentrations for total α were found to range from 0.002 to 0.030 Bq L(-1) and for total β from 0.023 to 1.351 Bq L(-1). Uranium concentrations ranging from 0.562 to 14.710 μg L(-1) were observed in drinking waters. Following the World Health Organisation rules, all investigated waters can be used as drinking water.
Environmental monitoring data review of a uranium ore processing facility in Argentina
International Nuclear Information System (INIS)
Bonetto, J.
2014-01-01
An uranium ore processing facility in the province of Mendoza (Argentina) that has produced uranium concentrate from 1954 to 1986 is currently undergoing the last steps of environmental restoration. The operator has been performing post-closure environmental monitoring since 1986, while the Nuclear Regulatory Authority (ARN) has been carrying out its own independent radiological environmental monitoring for verification purposes since its creation, in 1995. A detailed revision of ARN´s monitoring plan for uranium mining and milling facilities has been undergoing since 2013, starting with this particular site. Results obtained from long-time sampling locations (some of them currently unused) have been analyzed and potentially new sampling points have been studied and proposed. In this paper, some statistical analysis and comparison of sampling-points’ datasets are presented (specifically uranium and radium concentration in groundwater, surface water and sediments) with conclusions pertaining to their keeping or discarding as sampling points in future monitoring plans. (author)
A survey of natural uranium concentrations in drinking water supplies in Iran
International Nuclear Information System (INIS)
Alirezazadeh, N.; Garshasbi, N.
2003-01-01
Background: Measurement of background concentration of uranium in drinking water is very important for many reasons, specially, for human health. The uranium concentration in drinking water in many countries is a matter of concern for clinical and radioactive poisoning. Materials and methods: The uranium concentration in drinking water is determined using laser fluorimetric uranium analyzer. For this purpose after sampling, sample handling and sample preserving, sample preparation and treatment for reduction of organic matter, the concentration of uranium is measured. Results: To determine the uranium concentrations in drinking water in Iran, nearly 200 water samples were collected from all sources supplying drinking water in 21 provincial centers in the country. The wells were found to be the main source for drinking water. Uranium in the samples was measured by a laser fluorimetry technique. According to results, the concentration values found in the wells ranged from 1.0 to 10.90 μgL -1 , while nearly 95 percent of the cities had uranium concentrations in the wells at less than 4.70 μgL -1 . Surface waters showed uranium concentrations in the range of 0.75 to 2.58 μgL -1 . The daily intake of uranium from drinking water was estimated to range from 2.04 to 21.80 μgd -1 , with the mean value of 5.44 μgd -1 . Conclusion: Highest uranium mean concentration of 10.9 μgL -1 was found in Ardabil area where more studies should be done in that province in the future
Proterozoic strata-bound uranium deposits of Zambia and Zaire
International Nuclear Information System (INIS)
Meneghel, L.
1984-01-01
The Katanga System, host to uranium and copper mineralisation, is several thousands of metres thick and rests unconformably on an older complex of crystalline rocks and metasediments and is locally covered by Karoo sandstones or Kalahari sands. The deposition of the Katanga System took place during the Late Proterozoic in a wide complex basin extending from Shaba province in Zaire through a large part of Zambia and into eastern Angola. The sediments were affected by different grades of metamorphism, tectonic events, and by thermal events associated with post-tectonic metamorphism. At the base of Katanga system there are 84 known copper deposits and 42 uranium occurrences. It is suggested that all the known uranium and copper occurrences are of an essentially syngenetic sedimentary origin. The mineralisation is found in the Lower Roan Formation near the base of the Katanga System occurring in rocks produced in similar environmental conditions and thus being stratigraphic controlled, however, their areal distribution is localised producing a regional metal zonation. Many of the uranium occurrences have a typical vein aspect. These transgressive relationships are not inconsistent with a syngenetic origin as evidenced by the vein morphology. (author)
Uranium deposit of Bauzot (Saone et Loire)
International Nuclear Information System (INIS)
Carrat, G.H.
1956-01-01
The best known of the uranium ore deposits of the Morvan (a province of France) is in the form of a bundle of quartz-fluor lodes with pitchblende and B.P.G.C. ore. The pitchblende seems to have been deposited at different time in respect to the formation of the gangue minerals, but generally it is ore of the first-formed. The main concentrations of ore are always in the vicinity of dykes of basic crystalline rocks. (author) [fr
International Nuclear Information System (INIS)
Rodrigues Silva, J.I.; Melo Ferreira de, A.C.; Costa da, A.C.A
2009-01-01
The biosorption of uranium by the seaweed Sargassum filipendula was investigated under dynamic conditions at various bed heights. Our results indicate that a bed height of 40.0 cm (111.9 g biomass) was the most efficient for long-term operation of the continuous system. Our results also indicate that the effluent solutions produced are in accordance with Brazilian legislation for safe discharge of uranium in aqueous streams. The efficiency of the process increased with an increase in bed height from 5.0 to 40.0 cm due to changes in the transfer zone. In treatment of a real effluent contaminated with uranium, stable heavy metals and essential metals, 64% of the uranium was biosorbed, as well as the stable heavy metals chromium, lead and barium. The essential metals calcium, magnesium, iron and manganese were not biosorbed by the seaweed, in fact, their concentrations in the solution increased due to ion-exchange mechanisms with the constituent polysaccharides of the biomass. Another important result was the 85-87% reduction of mass obtained after drying and calcination of the biomass. This is a relevant indication that long-term storage of biomass loaded with radionuclides and heavy metals is possible after concentration of the contaminants. In the present work, the reduction in total mass of the loaded biomass was considerable, thus facilitating storage of the contaminated seaweed. (author)
International Nuclear Information System (INIS)
Fan, H.; He, D.; Wang, F.
2009-01-01
It has been considered that deposits in Baimianshi uranium field have similar features and ore-forming type, it is the syngenetic sedimentation that caused some U-bearing minerals to concentrate, and as a result of the enrichment in the late lithogenetic stage the deposit formed which is separate genesis to sandstone type and volcanic hydrothermal sub-type. This paper takes Huangnihu deposit in Baimianshi field as an example, and regards Baimianshi field as hydrothermal type according to research on intergrowth assemblage, fluid inclusions, U-Pb isotopic dating and Nd-Sr isotopic tracing. Ore minerals are mainly uraninite, brannerite, coffinite, etc, while the assistant gangue minerals are mainly galena, hematite, marcasite, blende, etc. The materials for uranium mineralization are mainly crust-derived rocks. Continuous extraction of uranium from the upper crust and basement granite by mantle-derived fluids with little of ore-forming elements may be responsible for the remobilization and transformation of uranium. Mixing of ore-enriched fluid with groundwater in some enclosed places overlain by basalt leads to the precipitation of ore-forming materials from the mixed fluid. There are three episodes of uranium mineralization: The first one is 160.4±0.5Ma, related to double-peak type volcanism, with basalt lithogenetic age of 172.8±7.7Ma and rhyolite lithogenetic age of 164.8±0.57Ma (from Chen Peirong, etc., 1999). The second one is 128±0.8Ma, related to Yanshanian Magmatic activities, for example, Danguanzhang rock mass and several phases of complements. The third one is about 100Ma, related to sub-volcanic rocks and dykes, namely quartz porphyry (99Ma) and diabase (105Ma). The above achievements will play an important part in the guidance of future prospecting in the deeper in that area. (author)
Uranium occurrences in the Gordonia and Kuruman districts
International Nuclear Information System (INIS)
Levin, M.
1978-11-01
This report highlights uranium occurrences discovered by the author in the Kuruman and Gordonia Districts. These discoveries are the result of follow-up work of the regional geological, hydrological and hydrochemical studies of the area, undertaken by the Geology Division of the Atomic Energy Board since 1974. A surficial uranium deposit was discovered on the farm Rus en Vrede in the Kuruman District, at the junction of a palaeo-river with the Kuruman River. Uranium occurs in carbonaceous diatomaceous earth, with surface samples assaying up to 308 ppm U 3 O 8 . As uranium is also present in calcrete 18 km south of this deposit, there is a distinct possibility that significant surficial deposits may occur under the Kalahari sand cover in this area. In the Gordonia District an interesting discovery was made on the farm Tsongnapan where four boreholes, drilled for water, intersected radioactive bands in the Dwyka Tillite Formation. These rocks, which outcrop in the northeast corner of the Tsongnapan, also proved to be radioactive. Some 35 km to the east of this occurrence, borehole logging indicated the existence of an anomalous zone near the base of the Dwyka. In some of these boreholes uranium anomalies were also found in the calcrete and gravel of the Kalahari Formation. It is evident, therefore, that the Gordonia District has the potential of becoming an economically important uranium province. A radiometric ground survey of one of the pans indicated that wind and water action is possibly responsible for the local dispersion and segregation of radioactive minerals [af
Finch, W.I.; Feng, S.; Zuyi, C.; McCammon, R.B.
1993-01-01
Four major types of uranium deposits occur in China: granite, volcanic, sandstone, and carbonaceous-siliceous-pelitic rock. These types are major sources of uranium in many parts of the world and account for about 95 percent of Chinese production. Descriptive models for each of these types record the diagnostic regional and local geologic features of the deposits that are important to genetic studies, exploration, and resource assessment. A fifth type of uranium deposit, metasomatite, is also modeled because of its high potential for production. These five types of uranium deposits occur irregularly in five tectonic provinces distributed from the northwest through central to southern China. ?? 1993 Oxford University Press.
Taxation of uranium mining in Canada and Australia
International Nuclear Information System (INIS)
Barnett, D.W.
1983-01-01
The objective of this paper is to compare the nature of the taxation schemes facing uranium mine operators in Australia's Northern Territory and in Canada's Province of Saskatchewan. The findings demonstrate that, although the Canadian system appropriates up to 85% of incremental sales revenue, it is extremely sensitive to industry profitability. Its Australian counterpart is, in contrast, a regressive scheme which, at the current selling price of yellowcake, captures a significantly larger proportion of available economic rent. (author)
Improvement of uranium production efficiency to meet China's nuclear power requirements
International Nuclear Information System (INIS)
Zhang, R.
1997-01-01
Recently China put the Qinshan Nuclear Power Plant, with an installed capacity of 300 MW, in the province of Zhejiang and the Daya Bay Nuclear Power Plant, with a total installed capacity of 2 x 900 MW, in commercial operation. China plans a rapid growth in nuclear power from 1995 to 2010. China's uranium production will therefore also enter a new period with nuclear power increasing. In order to meet the demand of nuclear power for uranium special attention has been paid to both technical progress improvement using management with the aim of reducing the cost of uranium production. The application of the trackless mining technique has enhanced the uranium mining productivity significantly. China has produced a radiometric sorter, model 5421-2 for pre-concentrating uranium run-of-mine ore. This effectively increases the uranium content in mill feed and decreases the operating cost of hydrometallurgical treatment. The in situ leach technique after blasting is applied underground in the Lantian Mine, in addition to the surface heap leaching, and has obtained a perfect result. The concentrated acid-curing, and ferric sulphate trickle leaching process, will soon be used in commercial operation for treating uranium ore grading -5 to -7 mm in size. The annual production capability of the Yining Mine will be extended to 100 tonnes U using improving in situ leaching technology. For the purpose of improving the uranium production efficiency much work has been done optimizing the distribution of production centres. China plans to expand its uranium production to meet the uranium requirements of the developing nuclear power plants. (author). 4 tabs
Radionuclides in waters and soil near the Lagoa Real uranium mine
International Nuclear Information System (INIS)
Souza, Susana Oliveira de; Freire, Fabinara Dantas; Dias, Dario M.; Veiga, Artur Jose Pires
2015-01-01
Uranium mining generates fuel for the nuclear power plants and it is the main source of income for the region of Caetite-BA. However, Non-Governmental Organizations claim that mining pollutes the environment and jeopardizes human health and safety. Besides uranium, the ground contains significant concentrations of thorium and of all radionuclides of its family, such as radium isotopes. In this framework, we carried out an independent study analyzing the concentration of the radionuclides activities 226, 228 Ra and 234,238 U in water samples and radionuclides 226 Ra, 232 Th and 40 K in soil samples using different techniques of nuclear spectrometry. The selection criteria for the collection points were their proximity to the uranium processing plant and to affluent rivers. The soil samples presented very low concentration of activity for radionuclides investigated, compared to the limits established of the exclusion, exemption and impartiality for radiation protection requirement given by the Regulator Position established by CNEN. The amount of radioisotopes appears consistent with a natural origin, thus it is not possible to state that the mining process in Caetite increases pollution or radiation exposure in a significant way. (author)
Radionuclides in waters and soil near the Lagoa Real uranium mine
Energy Technology Data Exchange (ETDEWEB)
Souza, Susana Oliveira de; Freire, Fabinara Dantas, E-mail: sosouza@ufs.br [Universidade Federal de Sergipe (UFS), Sao Cristovao, SE (Brazil). Departamento de Fisica; Kozlowska, Beata; Walencik-Lata, Agata, E-mail: beata.kozlowska@us.edu.pl [University of Silesia, Institute of Physics, Katowice (Poland); Dias, Dario M., E-mail: engenheirodario@gmail.com [Secretaria Municipal de Meio Ambiente e Turismo, Andarai, BA (Brazil); Veiga, Artur Jose Pires, E-mail: tk1@ibest.com [Universidade Estadual do Sudoeste da Bahia (UESB), Itapetinga, BA (Brazil). Departamento de Ciencias Exatas e Tecnologicas
2015-07-01
Uranium mining generates fuel for the nuclear power plants and it is the main source of income for the region of Caetite-BA. However, Non-Governmental Organizations claim that mining pollutes the environment and jeopardizes human health and safety. Besides uranium, the ground contains significant concentrations of thorium and of all radionuclides of its family, such as radium isotopes. In this framework, we carried out an independent study analyzing the concentration of the radionuclides activities {sup 226,} {sup 228}Ra and {sup 234,238}U in water samples and radionuclides {sup 226}Ra, {sup 232}Th and {sup 40}K in soil samples using different techniques of nuclear spectrometry. The selection criteria for the collection points were their proximity to the uranium processing plant and to affluent rivers. The soil samples presented very low concentration of activity for radionuclides investigated, compared to the limits established of the exclusion, exemption and impartiality for radiation protection requirement given by the Regulator Position established by CNEN. The amount of radioisotopes appears consistent with a natural origin, thus it is not possible to state that the mining process in Caetite increases pollution or radiation exposure in a significant way. (author)
International Nuclear Information System (INIS)
Cai Yuqi; Li Mangen
2002-01-01
The author mainly discusses the character of the depositional systems, geological structures and ore-bearing series in the south-central Longchuanjiang basin, and points out that the uranium mineralization is closely related to the two depositional discontinuities caused by the tectonic evolution. Based on the characteristics of uranium mineralization in the area, pitchblende, uranium blacks and phosphuranylite are discovered in No. 382 uranium deposit and radiometric super-micro-minerals in No. 381 deposit. The research on the uranium mineralization age in No. 382 deposit shows that the mineralization in the south-central part of the basin has genetically multi-staged
International Nuclear Information System (INIS)
Neff, T.L.; Jacoby, H.D.
1980-12-01
Discussed in this report are 1) how one might think about uranium demand, resources and supply, 2) how producers and consumers see the market and are likely to behave, including specifics about export and import commitments, and 3) how these actors are brought together in the international market. The general conclusion is that much of current anxiety about future uranium supply results primarily from a brief but difficult period in the mid- to late-1970's; and that current conditions and trends are favorable (at least to consumers) that there is now little basis for concern. Inventories contractual positions and producer commitments--when compared with realistic (or even unrealistic) demand estimates--imply a buyer's market for at least the next decade. The result will be considerable increases in market flexibility and resilience to shock, and real prices that are low relative to those of the past few years. There is a need to reconsider assumptions about desired directions of technological development, for many current programs were planned in an era of pessimism about uranium supply and process. Similar questions must be raided about nonproliferation policies that depend on some level of control of fuel supplies by the industrial nations. With a soft and more diversified uranium market, leverage that may have existed in the past is rapidly being eroded. Finally, as world prices turn soft, there may be significant problems created for U.S. uranium producers, who have relatively high costs in relation to several large-scale foreign suppliers
Directory of Open Access Journals (Sweden)
Zohreh Akbari Jonoosh
2016-09-01
Full Text Available Uranium separation and removal are important from environmental, public health, and strategic veiwpoints. Scientits have put great efforts to develop technologies for uranium removal and regeneration because of its important applications and beneficial uses. In this study, efforts have been made to synthesize a modified form of Fe3O4@SiO2 and benzamide uranium complexes that can be exploited to remove and adsorb uranium onto an adsorbent that can be recycled. In the first step, Fe3O4@SiO2 was synthesized and later modified with trimethoxysilane. The adsorbent was subsequently characterized by SEM and FTIR. In a second step, experiments were performed to determine optimum stirring speed, contact time, ion strength, and adsorbent reusability. Finally, the performance of the adsorbent was tested in samples of real wastewater. SEM and FTIR analyses confirmed the satisfactory synthesis and modification of Fe3O4@SiO2 Nps. Statistical analyses revealed that although contact time, ion strength, and stirring speed were effective in adsorbent performance, they only led to a removal enhancement of 5% and a decrease of only 17% with increasing RPM to 250 and the enhancement of ion strength to 1.5M. The highest U(VI removal efficiency in the synthetic solution was found to be 97%, which reduced to 49% in real wastewater samples. It was concluded that the nano-composite C14/SiO2_Fe3O4 adsorbent with its magnetic core and resistant surface not only offers the possibility for easy separation of urnaium from solutions but is also reusable and is only slightly affected by changes in stirring speed or ion strength. It, therefore, has a good capability for use as a U(VI adsorbent in wastewater treatment.
The uranium deposits of Ontario
International Nuclear Information System (INIS)
Robertson, J.A.
1981-01-01
The principal types of uranium deposits in Ontario are carbonatites and fenites, alkalic volcanic rocks, pegiatites, calc-silicate rocks, pyritic quartz-pebble conglomerates, polymictic conglomerates and some pelitic rocks, and various 'pitchblende' deposits including late Precambrian unconformities, possibly late Precambrian diabase dikes, and other unconformities: carbonates, sandstones, lignites, and semi-pelitic rocks of middle and upper Precambrian age. Only red unzoned pegmatite and the pyritic quartz-pebble conglomerate have supported production. Ontario reasonably assured and estimated resources in the economic and subeconomic categories in 1977 amounted to 553 000 tonnes U, and 1977 production was 4000 tonnes U. Measured, indicated, and inferred resources in the Elliot Lake - Agnew Lake area are at least 400 000 tonnes U. The latter deposits are also a significant thorium resource. Geological features reflecting major changes in physics and chemistry are prime controls on distribution of uranium deposits. Geological province and subprovince boundaries, major faults, higher metamorphic grades, domain boundaries related to quartz monzonite batholiths, alkalic complexes, and the distribution of carbonate rocks are examples of such geological features
Measurement of uranium in soil environment optimization of liquid fluorescent method improvement
International Nuclear Information System (INIS)
Qin Guangcheng; Li Yan
2013-01-01
Measurement of uranium in soil environment were introduced in this paper optimization improvement fluid fluorescence analysis method. Use 'on the determination of uranium in soil, rocks, etc. Samples of liquid fluorescent method' when measuring low environment soil samples can not meet the required precision of 8% or less in gansu province and method detection limit of 0.3 mg/kg or less. In affecting the method detection limit, recovery rate and precision of the soil sample decomposition temperature, measuring the temperature of the sample, sample pH value measurement, the background fluorescence measurement condition optimization of analysis is determined, the method detection limit of 0.133 mg/kg, the average recovery rate was 96.6%, the precision is 3.80%. The experimental results show that the method can meet the requirements for determination of trace uranium m environment soil samples. (authors)
International Nuclear Information System (INIS)
Majdalani, S.A.; Tavares, A.M.
2001-01-01
Uranium exploration in Brazil was started in 1952 by the Brazilian National Research Council. This led to the discovery of the first uranium deposits in Pocos de Caldas and Jacobina. These activities was later continued by the National Energy Commission/Comissao Nacional de Energia Nuclear (CNEN), formed in 1962. The founding of NUCLEBRAS at the end of 1974 marked the increasing effort of the country's uranium exploration programme. At this time only the Pocos de Caldas deposit was known with measurable resources. Due to the reorganization of the Brazilian nuclear programme in 1988, all uranium exploration in the country was stopped. By then, eight areas with uranium reserves has been identified. Brazil uranium resources in the RAR category at ≤ $80/kg U cost range are estimated to be 162,000 tonnes U, out of which 56,100 tonnes are in the ≤ $40/kg U cost range. Additional resources in the EAR-I category and the cost range ≤ 80/kg U are in the order of 100,200 tonnes U. The first production of uranium in Brazil, at the Osamu Utsumi mine (Pocos de Caldas deposit), started in 1982. Because of escalated costs and reduced demand, this activity was put on stand-by status between 1990 and 1992. The mine was restarted in 1993, but was stopped again in October 1995. The cumulative production of the mine to 1996 was 1241 tonnes U. The Lagoa Real deposit is currently being prepared as a new producing mine. (author)
International Nuclear Information System (INIS)
Yang Jianchun; Fang Genxian; Yang Yaxin
2003-01-01
On the base of the application of transient electromagnetic technique of paleochannel-type sandstone-hosted uranium deposits in Tengchong region of Yunan Province, this paper analyses the detect example. It discusses the theory foundation of TEM, fieldwork means, data processing and interpret. By contrast with routine electricity farad, the transient electromagnetic technique have the special merit and favorable space resolve gender under conditions of intricacy terrain. This means can get good effect in detecting paleochannel-type sandstone-hosted uranium deposits space position. It is a good reference for other prospecting and exploration work
Some aspects of the processing development for uranium ores treatment
International Nuclear Information System (INIS)
Bruno, J.B.
1982-01-01
It is discussed the methodology adopted by NUCLEBRAS to the processing development for uranium ores treatment. The used methodology has the following steps: exploratories studies, preliminaries stiudies and optimization studies. The studies include physical and chemical contained in the solution. As examples are cited the uranium ores treatment in Lagoa Real and Itataia. (A.B.) [pt
International Nuclear Information System (INIS)
Silva, Luciana Sousa
2011-01-01
Brazil has the seventh greatest geological uranium reserve in the world with approximately 310 thousand tons. The Lagoa Real Uranium Province, in the region of Caetite and Lagoa Real, situated in South Center Bahia, is considered the most important monomineralic province in Brazil. Urban population who lives in the uranium district in the cities of Caetite, Lagoa Real and Livramento de Nossa Senhora uses drinking water originated from public supply. In the rural area, characterized by frequent draughts, residents receive water from digged and drilled wells and from small dams and reservoirs, as well, which are supplied by the rains. This work determined the levels of total alpha and beta radioactivity and the uranium concentrations in several kinds of water consumed by urban and rural population from the Lagoa Real Uranium Province. Total α and β activities were determined with a low-level gas flow proportional detector. The uranium concentrations were determined with an inductive coupled plasma-mass spectrometer (ICP-MS). The results obtained were confronted with the latest World Health Organization's recommendations from 2011, the ordinance number 2914 of December 12 2011 from the Health Ministry and CONAMA's resolutions. Natural radiation levels varied from 0,0041 ± 0,0004 Bq.L -1 to 0,80 ± 0,04 Bq.L -1 for total alpha activity and from 0,045 ± 0,003 to 3,00 ± 0,2 Bq.L -1 for total beta activity. Having the WHO and the HM as parameter, just two underground water samples, one located in the city of Lagoa Real and the other in the city of Caetite presented total alpha concentration above the value of 0,5 Bq.L -1 described in its recommendations, 0,80 ± 0,040 Bq.L -1 and 0,57 ± 0,03 Bq.L -1 respectively. For total beta three samples presented radioactivity levels above the 1 Bq.L -1 limit recommended by the WHO and established by the Health Ministry; 3,00 ± 0,2 Bq.L -1 ; 1,63 ± 0,13 Bq.L -1 and 1,19 ± 0,07 Bq.L -1 ., all of them situated in the Lagoa
International Nuclear Information System (INIS)
Scislewski, Alexandro Rocha
2004-01-01
In the present research, the proposal was to develop a preliminary study about the geochemical behavior of determined chemical elements, mainly the uranium, during the action of weathering processes in the rocks that bear the uranium mineralizations of the Caetite-Lagoa Real region, State of Bahia, more specifically of the Jazida Cachoeira uranium mine. To reach this purpose were used samples that represent several stages of the milling process of the uranium ore, so selecting representatives of the host rock, the ore and the treated ore (waste from the milling plant) to be used in the laboratory-controlled experiments. The samples were dried, sieved and finally introduced in the reactors, these adapted from the Flow-Through Reactor of Brantley and Chen. In the geochemical point of view, the results of the experiments showed a distinct behavior between the samples. It was observed that the treated ore, in relation to the host rocks of the ore and the own ore, shown a faster and homogeneous interaction with the leaching solution; it was also noted that in the output solution of the treated ore samples existed a significant complexation of the uranium by the sulfate (S0 4 -2 ), ), instead of the non treated samples (host rock and ore) that were complexed mainly by the carbonate (C0 3 -2 ). These different results are attributed to the alterations imposed to the rock during the milling process, and occur mainly, during the acid attack in the leaching process of the milling plant. The results and conclusions of this research, in spite of been preliminary, are essential to understand the behavior of the geochemical speciation of the effluent solutions; to understand the alterations of a rock matrix, and finally, to understand the migration chemical behavior of the related chemical elements. It is expected that these results contribute, in the future, to a deeper knowledge of the processes that control the chemical composition of the natural waters from this region in
International Nuclear Information System (INIS)
Ferguson, J.
1988-01-01
In identifying uranium provinces, and, more importantly, mineralized zones within these provinces, it is of paramount importance to attempt to trace the geochemical behaviour of an element through all stages of Earth's evolution. Aspects that need to be addressed in this regard include solar abundance levels and fractionation processes during accretion, changing patterns of crustal evolution, effects of an evolving atmosphere, and the weathering cycle. Abundance patterns and partition coefficients of some of the siderophile elements in mantle rocks lend support to a multistage accretionary process. Lack of a terrestrial record in the first 500 Ma necessitates that lunar models be invoked, which suggests that early fractionation of a mafic/ultramafic magma resulted in an anorthositic crust. Fractionation of the mantle and transfer of materials to the upper levels must be central to any model invoked for development of the crust. Given high heat flow conditions in the early Archaean it would seem inescapable that the process of sea floor spreading and plate tectonics was an ongoing process. If the plate tectonic model is taken back to 3500 Ma, and assuming current speading rates, then about half of the mantle has passed through the irreversible differentiation cycle. Arguments in support of recycled material must be balanced against mantle metasomatism effects. With the associated advent of partial melting of the mantle material a partitioning of minor and trace elements into the melt fraction would take place. The early primitive mafic and ultramafic komatiites exemplify this feature by concentrating U and Th by a factor of 5 compared to chondritic abundances. It is of tantamount importance to understand the generation of the magmas in order to predict which are the 'fertile' bodies in terms of radioelement concentrations. In that the granitoid magmas image their source compositions, the association of high radioelements will primarily be source-dependent. Uranium
International Nuclear Information System (INIS)
Zhang Wanliang; Zou Maoqing; Shao Fei; Nie Bin
2009-01-01
Taoshan uranium field is occurred in the Taoshan composite batholith in the central Jiangxi Province. The main body of the batholith was formed in Triassic-Early Cretaceous. In Late Cretaceous-Eogene, NE strike fault structure and dike belt were developed in the batholith. From the north to the south, there are successive Xiaobu-Matian dike-structural belt, Wangnitian dike- structural belt, Huangtan-Yueyuan dike-structural belt, Xibei-Shangluo dike-structural belt, Jipoling dike-structural belt, Wangce dike-structural belt and Shiyuanling dike-structural belt. These belts are controlled by the main fault, share the same space and similar time with the uranium mineralization, which is one of the important factors in positioning the uranium ore as well as the prospecting direction of exploration. (authors)
Uranium resources and requirements
International Nuclear Information System (INIS)
Silver, J.M.; Wright, W.J.
1975-08-01
Australia has about 19% of the reasonably assured resources of uranium in the Western World recoverable at costs of less than $A20 per kilogram, or about 9% of the resources (reasonably assured and estimated additional) recoverable at costs of less than $A30 per kilogram. Australia's potential for further discoveries of uranium is good. Nevertheless, if Australia did not export any of these resources it would probably have only a marginal effect on the development of nuclear power; other resources would be exploited earlier and prices would rise, but not sufficiently to make the costs of nuclear power unattractive. On the other hand, this policy could deny to Australia real benefits in foreign currency earnings, employment and national development. (author)
National uranium resource evaluation, Las Vegas Quadrangle, Nevada, Arizona, and California
International Nuclear Information System (INIS)
Johnson, C.; Glynn, J.
1982-03-01
The Las Vegas 1 0 x 2 0 quadrangle, Nevada, Arizona, and California, contains rocks and structures from Precambrian through Holocene in age. It lies within the Basin and Range physiographic province adjacent to the westernmost portion of the Colorado Plateau. Miocene nonmarine sedimentary rocks of the Horse Spring Formation contain in excess of 100 tons U 3 O 8 in deposits at a grade of 0.01% or greater, and therefore meet National Uranium Resource Evaluation base criteria for uranium favorability. One favorable area lies in the South Virgin Mountains at the type locality of the Horse Spring Formation, although the favorable environment extends into the unevaluated Lake Mead National Recreation Area and Desert National Wildlife Range. Environments within the Las Vegas Quadrangle considered unfavorable for uranium include the Shinarump Conglomerate member of the Triassic Chinle Formation, Mesozoic sediments of the Glen Canyon Group, Precambrian pegmatites, Pliocene and Quaternary calcrete, Laramide thrust faults, and a late Precambrian unconformity
Geologic-radiometric techniques applied for uranium prospection at the Hierro-Cayo Largo area
International Nuclear Information System (INIS)
Gongora, L.E.; Olivera, J.
1995-01-01
Using geologic-radiometric techniques uraniferous anomalies were evaluated at the Hierro-Cayo Largo area located in Pinar del Rio province. During the uranium prospection works at most promising areas, geologic itineraries and gamma ray, radon emanation spectrometric survey were done. Trenches were made and some boreholes were drilled (up to 20-30 m depth). In addition a lot of samples were taken in order to determine the amount of U, Ra, Th, y K by spectrometric techniques. As result of this investigation, a geological placing, a mineralogical and geochemical characteristic of uraniferous mineralization was possible to find out. The appropriate prospection indications for uranium exploration at Esperanza geologic zone were defined
Energy Technology Data Exchange (ETDEWEB)
Lozano, F.; Ruiz Sanchez, J.
2015-07-01
The closure of the uranium mines of La Haba and Saelices el chico (Badajoz y Salamca provinces, respectively) are two examples of environmental restoration of mining uranium and dismantling of uranium concentrates plants. Activities carried out are described with the aim of ensuring that, once completed, environmental and radiological conditions are as similar as possible to the existing pre-exploitation, as well as the current situation in both sites with actions current and/or planned. (Author)
International Uranium Resources Evaluation Project (IUREP) national favourability studies: Guatemala
International Nuclear Information System (INIS)
1977-08-01
Before 1959 a private individual (Mr. Rene Abularach) is reported to have made an airborne radiometric survey of the Sierra de las Minas and Sierra Madre Ranges. Although many anomalies were detected by this survey, none were verified in the ground survey followup, despite apparently adequate flight control. In 1968 a United Nations Special Fund Mineral Survey Project completed over 1,000 km of carborne radiometric survey with geiger counter readings at 500 m intervals. No anomalies were detected, but background radioactivity for several formations and geologic environments was established. In 1969 the Guatemalan government solicited the IAEA for technical assistance In conducting a preliminary uranium favorability study designed to formulate recommendations for a national radioactive ore prospecting program. A carborne radiometric survey was made of environments theoretically favorable for uranium deposition, with spot geological and radiometric examinations being .conducted in the more favorable areas. All Important mining regions of Guatemala except the leterites and the ultrabasics were visited. No evidence of a uranium province was observed 1n these field investigations and the recommendation was made that the government not embark on a more detailed national prospecting program at that time. At the time of completion of the IAEA-Guatemalan government (GOG) reconnaissance program in 1971, no uranium reserves or resources were known. More recent information on uranium occurrences and resources 1n Guatemala does not appear to be available. Information on more recent uranium reconnaissance than that undertaken during 1971 IAEA-GOG study is lacking. However, in more recent years the country's mineral potential has been generally evaluated with the aid of the UN and ICAITI (Central American Research Institute for Industry). Except for quarry materials, the state owns all minerals. The state has priority on purchase of any mineral production needed for the country
International Nuclear Information System (INIS)
Chen Guihua
2001-01-01
Nanling is a complicated tectonomagmatic belt. It is also an important uranium-polymetallic metallogenic belt. On the basis of the research achievements of previous researchers, through the detailed stratigraphic, lithologic, litho-paleo-geographic, geochronologic and geochemical studies and the processing of gravimetric and magnetic data, as well as the information extraction of remote sensing data, the authors come to the following conclusions: (1) The Sannan-Xunwu fault is a long-lived (from the Early Sinian to recent time) EW-trending fault; (2) The earth crust in Nanling experienced three time opening-closing with different scales; (3) The Anyuan-Xunwu area is a large thermo-upwelling extensional structure; (4) The above area is considered to be favourable for the formation of rich-large uranium deposit
Natural uranium and 226Ra in bottled potable waters of Argentina
International Nuclear Information System (INIS)
Bomben, Ana M.; Palacios, Miguel A.
2001-01-01
This paper presents the results obtained of the measurement of the natural uranium and 226 Ra concentrations carried out on 345 drinking water samples coming from different provinces of Argentina. The samples were collected from tap water systems and private wells. Six bottled mineral waters samples, selected from those most extensively consumed, were also analyzed. The natural uranium concentration was determined by a fluorimetric procedure and 226 Ra by the 222 Rn emanation technique and liquid scintillation counting. Values ranging from 0,03 to 50 μg L -1 of natural uranium and concentrations up to 22 mBq L -1 were found in the drinking water samples analyzed. Natural uranium concentrations from 0,04 to 3,8 μg L -1 and 226 Ra concentrations up to 2,4 mBq L -1 were measured in the bottled mineral waters samples. Based on the water intake rate and the measured concentrations of both radionuclides analyzed, an annual collective effective dose of 1,5 man Sv and an average committed effective dose of 0,5 μSv a -1 , were calculated for the City of Buenos Aires inhabitants. (author)
Uranium under its depleted state
International Nuclear Information System (INIS)
2001-01-01
This day organised by the SFRP, with the help of the Army Health service, the service of radiation protection of Army and IPSN is an information day to inform the public about the real toxicity of uranium, and its becoming in man and environment, about the risks during the use of depleted uranium and eventual consequences of its dispersion after a conflict, to give information on how is managed the protection of workers (civil or military ones) and what is really the situation of French military personnel in these conflicts. The news have brought to the shore cases of leukemia it is necessary to bring some information to the origin of this disease. (N.C.)
International Nuclear Information System (INIS)
Hamdoun, N.A.
2007-01-01
The article includes a historical preface about uranium, discovery of portability of sequential fission of uranium, uranium existence, basic raw materials, secondary raw materials, uranium's physical and chemical properties, uranium extraction, nuclear fuel cycle, logistics and estimation of the amount of uranium reserves, producing countries of concentrated uranium oxides and percentage of the world's total production, civilian and military uses of uranium. The use of depleted uranium in the Gulf War, the Balkans and Iraq has caused political and environmental effects which are complex, raising problems and questions about the effects that nuclear compounds left on human health and environment.
Isotope exchange between gaseous hydrogen and uranium hydride powder
International Nuclear Information System (INIS)
Shugard, Andrew D.; Buffleben, George M.; Johnson, Terry A.; Robinson, David B.
2014-01-01
Highlights: • Isotope exchange between hydrogen gas and uranium hydride powder can be rapid and reversible. • Gas–solid exchange rate is controlled by transport within ∼0.7 μm hydride particles. • Gas chromatographic separation of hydrogen isotopes using uranium hydride is feasible. - Abstract: Isotope exchange between gaseous hydrogen and solid uranium hydride has been studied by flowing hydrogen (deuterium) gas through packed powder beds of uranium deuteride (hydride). We used a residual gas analyzer system to perform real-time analysis of the effluent gas composition. We also developed an exchange and transport model and, by fitting it to the experimental data, extracted kinetic parameters for the isotope exchange reaction. Our results suggest that, from approximately 70 to 700 kPa and 25 to 400 °C, the gas-to-solid exchange rate is controlled by hydrogen and deuterium transport within the ∼0.7 μm diameter uranium hydride particles. We use our kinetic parameters to show that gas chromatographic separation of hydrogen and deuterium using uranium hydride could be feasible
Uranium extraction from gold-uranium ores
Energy Technology Data Exchange (ETDEWEB)
Laskorin, B.N.; Golynko, Z.Sh.
1981-01-01
The process of uranium extraction from gold-uranium ores in the South Africa is considered. Flowsheets of reprocessing gold-uranium conglomerates, pile processing and uranium extraction from the ores are presented. Continuous counter flow ion-exchange process of uranium extraction using strong-active or weak-active resins is noted to be the most perspective and economical one. The ion-exchange uranium separation with the succeeding extraction is also the perspective one.
Geology of uranium deposits in the southern part of the Rocky Mountain province of Colorado
International Nuclear Information System (INIS)
Malan, R.C.
1983-07-01
This report summarizes the geology of uranium deposits in the southern part of the Rocky Mountains of Colorado, an area of about 20,000 square miles. In January 1966, combined ore reserves and ore production at 28 uranium deposits were about 685,000 tons of ore averaging 0.24 percent U 3 O 8 (3.32 million pounds U 3 O 8 ). About half of these deposits each contain <1,000 tons of ore. The two largest deposits, the Pitch in the Marshall Pass locality southwest of Salida and the T-1 in the Cochetopa locality southeast of Gunnison, account for about 90 percent of all production and available reserves. The probability in excellent for major expansion of reserves in Marshall Pass and is favorable at a few other vein localities. There are six types of uranium deposits, and there were at least four ages of emplacement of these deposits in the southern part of the Colorado Rockies. There are eight types of host rocks of eight different ages. Veins and stratiform deposits each account for about 40 percent of the total number of deposits, but the veins of early and middle Tertiary age account for nearly all of the total reserves plus production. The remaining 20 percent of the deposits include uraniferous pegmatites, irregular disseminations in porphyry, and other less important types. The wall rocks at the large Tertiary vein deposits in the southern part of the Rocky Mountains of Colorado are Paleozoic and Mesozoic sedimentary rocks, whereas Precambrian metamorphic wall rocks predominate at the large veins in the Front Range of the northern Colorado Rockies. Metallogenetic considerations and tectonic influences affecting the distribution of uranium in Colorado and in adjacent portions of the western United States are analyzed
Radioecological problems in a region of natural-uranium province (Kyrgyzstan)
International Nuclear Information System (INIS)
Djenbaev, B.M.; Zholboldiev, B.T.
2014-01-01
Full text : At present the attempts have been made in our Republic for solving the problems concerning heritage of uranium ores extraction and processing in places where several thousands of tons of radioactively polluted wastes are accumulated, posing potential threat for contamination of the environment and for people's health. The scientists of the Kyrgyz Republic and other countries actively work over the above mentioned problems solution : several international ISTC, IAEA and other projects were fulfilled, the material and technical basis of specialized laboratories became better, the results were obtained for presentation and discussion. In all these laboratories different kinds of effective semi-conductor germanium detectors were used for analysis of radionuclides gamma-spectra in tail materials and samples of the environment
International Nuclear Information System (INIS)
Colhoun, C.
1982-01-01
The spot market is always quoted for the price of uranium because little information is available about long-term contracts. A review of the development of spot market prices shows the same price curve swings that occur with all raw materials. Future long-term contracts will probably be lower to reflect spot market prices, which are currently in the real-value range of $30-$35. An upswing in the price of uranium could come in the next few months as utilities begin making purchases and trading from stockpiles. The US, unlike Europe and Japan, has already reached a supply and demand point where the spot market share is increasing. Forecasters cannot project the market price, they can only predict the presence of an oscillating spot or a secondary market. 5 figures
Method for converting uranium oxides to uranium metal
International Nuclear Information System (INIS)
Duerksen, W.K.
1988-01-01
A method for converting uranium oxide to uranium metal is described comprising the steps of heating uranium oxide in the presence of a reducing agent to a temperature sufficient to reduce the uranium oxide to uranium metal and form a heterogeneous mixture of a uranium metal product and oxide by-products, heating the mixture in a hydrogen atmosphere at a temperature sufficient to convert uranium metal in the mixture to uranium hydride, cooling the resulting uranium hydride-containing mixture to a temperature sufficient to produce a ferromagnetic transition in the uranium hydride, magnetically separating the cooled uranium hydride from the mixture, and thereafter heating the separated uranium hydride in an inert atmosphere to a temperature sufficient to convert the uranium hydride to uranium metal
Perception of radon risk in typical non-uranium mines in China
International Nuclear Information System (INIS)
Fu Yinhua; Sun Quanfu; Du Weixia; Lei Suwen; Lei Shujie; Wang Haijun; Qian Yekan; Li Xiaoyin; Su Xu
2008-01-01
Objective: To investigate the perception of risk flora occupational exposure to radon among the non-uranium miners in China, and to explore its major influence factors. Methods: 2836 workers from 24 mines in 9 provinces/regions were interviewed. Logit regress analysis was used to identify the major influence factors. Results: Among the interviewed mine workers, 13.3% of them had heard of radon, 29.0% of those miners who had heard of radon had some knowledge of the source of radon. Only 1.8% of the investigated mine workers had correct perception of health risk resulted from exposure to radon. The major factors to influence the radon risk perception included education degree and type of employment, perception was lower in those miners with low education or temporally employed. Perception level differed by province/regions and mines. Sex, age, and working length of the current job were not the main factors to influence the risk perception. Conclusions: The perception of radon risk resulted from occupational exposure among the Chinese non-uranium mine workers is low. More works are needed to effectively implement notification of occupational health hazards, which is stipulated by Chinese law on prevention and control of occupational disease, and one of the important factors in radon mitigation in mines. (authors)
International Nuclear Information System (INIS)
Guo Zhitian.
1986-01-01
According to the evolution history of the crust the region is divided into three Precambrian structural structural units: (1) Archaean craton; (2) Early Proterozoic zone of fold; (3) Middle-late Proterozoic depression zone. The Archaean-craton mainly consists of granite complex and metasediments. They form the first generation of uranium sources. Proterozoic is characterized by the obvious cycle of sedimentation which consists of the second generation of uranium source. There were multiplestage and congenetic nature in the formation of uranium deposit. The mineralization of uranium coincides with geotectonicdeveloping stage -- igneous activity -- metamorphism in their time. The formation of uranium deposits generally underwent the weathering and erosion of original uraniferous bodies-the migration, redeposition and reformed concentration by metamorphism and metamorphosed hydrothermal solution, and the mineralization was not only of intermittence, but also of inheritance. The evolutional process of forming uranium deposits undergoing various geological function of a structural cycle in the uranium geochemical anomalous area is called uranium mineralizational cycle. The Northeast of Northern China Platform had undergone multiple times structural movements causing migration and concentration of uranium and having mutiple cycle mineralizational character. Corresponding to the three main developing stages of the crustal evolution the Precambrian uranium mineralization in the Northeast of northern China platform area may be divided into three cycles: Late Archaeozoic mineralizational cycle, Early Proterozoic mineralizational cycle, and Middle Proterozoic mineralizational cycle. It is possible to search for potential uranium metallogenetic provinces to study the crustal evolution and the multiple cycle characters of uranium minerogenetic process in the Northern China platform
Development of the Alligator Rivers uranium deposits
International Nuclear Information System (INIS)
Bath, L.J.; Farthing, J.W.; Warner, R.K.
1980-01-01
The Alligator Rivers Uranium Province in the Northern Territory of Australia has proven uranium deposits at Jabiluka, Ranger, Koongarra and Nabarlek which contain more than 80% of the country's low-cost reasonably assured uranium resources estimated to be 290,000 t U. Following the Government's decision in 1977 to proceed with the further development of Australia's uranium resources, the region is destined to become a major producer of U 3 O 8 for export. At the time of the decision provision was made for strict controls to protect the environment, the granting of Aboriginal land rights and the creation of a major national park. The paper describes the progress made to achieve these objectives. The open-cut mining methods to be used at Ranger, Koongarra and Nabarlek are described, as well as the underground mining operations proposed for Jabiluka. Each of the treatment plants will use the conventional acid leach, solvent extraction purification process for uranium recovery. The characteristics of the treatment operations are outlined. The water-management schemes, tailings disposal methods and procedures for environment protection are also discussed. The proposed initial production capacities of the operations are: Jabiluka 2540 (expanding to 7630 in the fifth year of production); Ranger 2540 (expanding to 5080 when commercially practicable); Koongarra 850; and Nabarlek 920 t U/a. Both Nabarlek and Ranger have been granted Government development approval and construction is proceeding at each site with the expectation that normal commercial production will commence towards the end of 1980 and 1981, respectively. Planning for the Jabiluka and Koongarra projects has reached an advanced stage; each are undergoing environmental procedures and will have to reach agreement with the Aboriginals on environmental and other matters before site work can commence. (author)
Method for converting uranium oxides to uranium metal
Duerksen, Walter K.
1988-01-01
A process is described for converting scrap and waste uranium oxide to uranium metal. The uranium oxide is sequentially reduced with a suitable reducing agent to a mixture of uranium metal and oxide products. The uranium metal is then converted to uranium hydride and the uranium hydride-containing mixture is then cooled to a temperature less than -100.degree. C. in an inert liquid which renders the uranium hydride ferromagnetic. The uranium hydride is then magnetically separated from the cooled mixture. The separated uranium hydride is readily converted to uranium metal by heating in an inert atmosphere. This process is environmentally acceptable and eliminates the use of hydrogen fluoride as well as the explosive conditions encountered in the previously employed bomb-reduction processes utilized for converting uranium oxides to uranium metal.
Investigation of remote sensing geology in the northern Anxi area of Gansu Province
International Nuclear Information System (INIS)
Dai Wenhan
1993-07-01
The study of 1 : 50,000 remote sensing geology survey and prognosis of gold (uranium) mineralization in the area of northern Anxi of Gansu province has been completed. The synthetical remote sensing and multi-source information compounding technologies, such as land-satellites TM and MSS images, airborne color infrared photography and infrared ray scanning digital images, are used in the study. On the basis of information enhancement and extraction of remote-sensing images, using the theory of remote sensing to explore mineral deposits and the field investigations, many achievements have been reached, such as applications of synthetical remote sensing technology, fundamental study of geology, prognosis of gold (uranium) minerals and 1 : 50,000 remote-geologic mapping. 21 mineral resource maps and geologic maps are obtained. Nearly one thousand of altered rock zones are interpreted and found. 71 new gold anomaly hydrothermal alteration zones and 23 gold mineralized places are discovered (maximum Au 71 x 10 -6 ). 17 minerogeneration prospective areas, 67 gold-ore searching targets and favorable areas of uranium mineralization are identified. It gives important materials for searching new mines
International Nuclear Information System (INIS)
Lima, Tatiana Aparecida Fernandes de; Rios, Francisco Javier; Fuzikawa, Kazuo; Oliveira, Lucilia A. Ramos de; Oliveira, Elizabeth Kerpe; Neves, Jose Marques Correia; Prates, Sonia Pinto
2009-01-01
Fluid composition studies, throughout fluid inclusions (FI), contribute to improve the understanding of mineral deposits. FI correspond to small portions of fluids trapped in minerals by many processes that preserve relevant information related to fluid composition which forms ore deposits. Microscopy and microthermometry techniques applied to fluid inclusions studies of opaque and/or dark minerals use infrared light (IR). A specific stage heating/cooling that allows working in the near infrared (NIR). Thus, the infrared stage model FTIR600 Linkam coupled the IR OLYMPUS BX51, with the automatic controllers LNP 94/2 and TMS 94, and software Linksys 32 - Linkam installed in computer was implemented and tested. An infrared QUICAM fast 1394 QIMAGING TM camera with the program QCAPTURE SUITE was acquisition for images capture and adapted the new system. This infrared stage Linkam FTIR600 reach temperatures between -196 deg C to +600 deg C, with the differential of working in the NIR; it is all automated, obtaining computerized data, graphics in real time of analysis and storage the data. It also controls the speed of the experiment (up to 130 deg C/min); it runs consecutively heating and cooling with a small N 2 (l) consuming; besides greater results repeatability, obtaining accurate and precise temperatures. Actually the Linkam stage FTIR600 is operating in the Metallogenesis and Fluid Inclusions Laboratory (LIFM) at CDTN/CNEN. Uranium ore and/or others mineralization studies which shows dark or opaque mineral have been developed. The uranium mineralization in the Lagoa Real Uraniferous Province, Bahia, Brazil, shows several rock-forming minerals together with the dark and opaque minerals (garnet, magnetite, pyroxene) emphasized in the present work. (author)
International Nuclear Information System (INIS)
Cuney, M.; Pagel, M.; Leroy, J.
1992-01-01
First, this book presents the physico-chemical properties of Uranium and the consequences which can be deduced from the study of numerous geological process. The authors describe natural distribution of Uranium at different scales and on different supports, and main Uranium minerals. A great place in the book is assigned to description and classification of uranium deposits. The book gives also notions on prospection and exploitation of uranium deposits. Historical aspects of Uranium economical development (Uranium resources, production, supply and demand, operating costs) are given in the last chapter. 7 refs., 17 figs
The geology of the Collins Bay uranium deposit, Saskatchewan
International Nuclear Information System (INIS)
Jones, B.E.
1980-01-01
The Collins Bay deposit lies within the Churchill Province on the western edge of the Wollaston lithostructural domain where it underlies the eastern edge of the Helikian Athabasca Formation. It is 6 miles north-northeast of the Rabbit Lake mine. Two principal zones of uranium mineralization are described. The A zone, a partly eroded, high-grade pod of metal oxide and arsenides sheathed by clay-like minerals, which trends north-northeast and lies under 25 to 40 feet of water; and the B zone, which lies 6 000 ft south of the A, subcrops under till cover and is a partly eroded zone composed of metal oxide and arsenides which occur within variably altered Athabasca Formation. The deposit is typical of the unconformity-type uranium-nickel deposits of the Athabasca Basin. Observed features fit well with the diagenetic-hydrothermal model for such deposts. (auth)
International Nuclear Information System (INIS)
Poty, B.; Cuney, M.; Bruneton, P.; Virlogeux, D.; Capus, G.
2010-01-01
With the worldwide revival of nuclear energy comes the question of uranium reserves. For more than 20 years, nuclear energy has been neglected and uranium prospecting has been practically abandoned. Therefore, present day production covers only 70% of needs and stocks are decreasing. Production is to double by 2030 which represents a huge industrial challenge. The FBR-type reactors technology, which allows to consume the whole uranium content of the fuel, is developing in several countries and will ensure the long-term development of nuclear fission. However, the implementation of these reactors (the generation 4) will be progressive during the second half of the 21. century. For this reason an active search for uranium ores will be necessary during the whole 21. century to ensure the fueling of light water reactors which are huge uranium consumers. This dossier covers all the aspects of natural uranium production: mineralogy, geochemistry, types of deposits, world distribution of deposits with a particular attention given to French deposits, the exploitation of which is abandoned today. Finally, exploitation, ore processing and the economical aspects are presented. Contents: 1 - the uranium element and its minerals: from uranium discovery to its industrial utilization, the main uranium minerals (minerals with tetravalent uranium, minerals with hexavalent uranium); 2 - uranium in the Earth's crust and its geochemical properties: distribution (in sedimentary rocks, in magmatic rocks, in metamorphic rocks, in soils and vegetation), geochemistry (uranium solubility and valence in magmas, uranium speciation in aqueous solution, solubility of the main uranium minerals in aqueous solution, uranium mobilization and precipitation); 3 - geology of the main types of uranium deposits: economical criteria for a deposit, structural diversity of deposits, classification, world distribution of deposits, distribution of deposits with time, superficial deposits, uranium
Demonstration of near-real-time accounting: the AGNS 1980-81 miniruns
International Nuclear Information System (INIS)
Dayem, H.A.; Baker, A.L.; Cobb, D.D.; Hakkila, E.A.; Ostenak, C.A.
1984-01-01
Near-real-time nuclear materials accounting was demonstrated in a series of experiments at the Allied-General Nuclear Services (AGNS) Barnwell Nuclear Fuels Plant. For each experiment, the second and third plutonium cycles were operated continuously for 1 wk processing uranium solutions. Process data were collected in near-real time by the AGNS computerized nuclear materials control and accounting system and were analyzed for uranium removals using decision analysis techniques. Although the measurement system primarily consisted of process-monitoring measurements that were not optimized for near-real-time accounting, the results of uranium-removal tests showed that removals and unexpected losses from the process area can be detected. Los Alamos used process-grade measurements to close hourly materials balances. Loss-detection sensitivities for 1 day of between 4 and 18 kg of uranium, at 50% detection probability and 2.5% false-alarm probability, were calculated for selected accounting areas. Using pulsed-column inventory estimators, we calculated a total four-column inventory that was within 10% of column dump measurements. Loss-detection sensitivity could be improved by incorporating online waste stream measurements, improving laboratory measurements for process streams, and refining the pulsed-column inventory estimates
Energy Technology Data Exchange (ETDEWEB)
Oliveira, Lucilia Aparecida Ramos de; Rios, Francisco Javier; Chaves, Alexandre de Oliveira; Pereira, Ana Rosa Passos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)]. E-mail: laro@cdtn.br
2007-07-01
The acknowledgement of the geological history of a ore reserve allows to infer relative to a large area with possibility to contain the large mineral content or even give the localization of new anomalies or mineral reserve. The study of ore reserve genesis is of great importance for the stages to obtain the mineral, from the prospection until the mineral mining. Fluid inclusions (FI) are fluid quantities which are imprison in the minerals during the formation process or some process where deformation occurs. The study of fluid inclusions, together with the petrographic mapping of the blades associated to the uranium para genesis of Lagoa Real, Brazil, are been used for a better comprehension of the uranium orogenesis. The main analysis techniques used in this context were the petrography and microthermometry. With the petrographic analysis fluid inclusions were observed and mapped in various minerals present in rocks associated to uranium mineralization, such as amphiboles, pyroxenes and grenades. The micro thermometric studies were only performed in the pyroxenes and the grenades due to the fluid inclusions types found in these minerals, and also the supposed relationships that those minerals have with uranium mineralization at that region. (author)
International Nuclear Information System (INIS)
Navarra, P.R.; Sardin, P.G.; Urquiza, L.; Bernal, G.J.; Guzman Lobos, D.
1993-01-01
Preliminary results of the resources estimation carried out in the Cerro Solo uranium ore deposit, located in the Chubut Province, 1900 km SW from Buenos Aires and 380 Km W from Trelew, presented in tonnes of uranium recoverable at costs up to U$S 80/kgU, are as follows: a) Reasonable assured resources (indicated): 800 tU; b) Estimates Additional Resources (inferred): 2200 tU. Economic evaluation at the order-of-magnitude level, performed using the grade-tonnage model of the deposit, resulted a useful tool in the different stages of the project to identify the influence of technical parameters on the potential profitability. Research about feasibility of in-situ leaching method of exploitation for this deposit introduces an interesting alternative for future uranium production in the country. (Author)
International Nuclear Information System (INIS)
Modnikov, I.S.; Skvortsova, K.V.; Chesnokov, L.V.
1974-01-01
The article gives a comparative description of and the age relationships between uranium-molybdenum, gold and fluorite mineralizations in the areas of development of adhesite-diorite and liparite-granite vulcanoplutonic formations, which are most fully and intensively manifest in the intra-anticlinal and median blocks of folded regions in the final stages of geosynclinal development or during the final stages of tectono-magmatic activation. These formations usually fill vulcano-tectonic depression structures - overlaid troughs and inherited delections. The geological and geochemical data are evidence of the close temporal link between the hydrothermal process of ore formation and the type and scale of manifestations of the vulcano-plutonic magmatism that is responsible for the general geochemical features of the ores of deposits of various types. The formation of gold, fluorite and uranium-molybdenum deposits occurred immediately after the completion of effusive and intrusive magmatism during a single metallogenic cycle. The spatial distribution of the ore fields and deposits depends chiefly on the peculiarities of the tectonic make-up of the depression structures, and also on the type and scale of the manifestations of vulcano-plutonic magmatism. (B.Ya.)
Activities on nuclear energy introduction in the SR of Serbia without territory of provinces
International Nuclear Information System (INIS)
Boljanac, C.; Vukovic, D.; Putnik, S.; Tankosic, D.
1984-01-01
In the paper the review of the past and the present activities on nuclear energy introduction in the SR Serbia without territory of provinces is given. The program of the activities in this field includes extensive spectrum of different tasks from investigation of the nuclear raw material and the development in the field of nonconventional uranium production, through studies in fuel cycle area up to the preparatory activities for the nuclear power plant construction. (author)
Muhammad Yusuf
2013-01-01
One of the main functions of the government of North Sumatra Province is how to reduce the gap between the district / city in the province of North Sumatra. A regional disparity is the ratio of real per capita income among regions with per capita real income of the province. This study aims to analyze the development gap among districts / cities in North Sumatra. In addition, this study also analyzes the Klasen typology at each district / city in North Sumatra. The data’s that used in this st...
International Nuclear Information System (INIS)
Gingrich, J.E.; Foy, M.F.
1977-01-01
Sediments samples were collected from streams draining the Koongarra uranium deposit and the small uranium mines in the South Alligator Valley. Determinations for U, Cu and Pb on various size fractions taken from each of these samples indicated that the best results were obtained for U from the minus 200-mesh fraction, but the train from the Koongarra ore deposit was very short. Cu and Pb were not found to be very useful as indicator elements for U. Alpha-track films were used to determine the Rn content of each sample and the ratio of alpha-track film reading to U content was found to define anomalous drainage areas around the mineralization in the Koongarra area. The areas so defined were of sufficient magnitude to be defined in a reconnaissance stream sediment programme
Source identification of uranium-containing materials at mine legacy sites in Portugal.
Keatley, A C; Martin, P G; Hallam, K R; Payton, O D; Awbery, R; Carvalho, F P; Oliveira, J M; Silva, L; Malta, M; Scott, T B
2018-03-01
Whilst prior nuclear forensic studies have focused on identifying signatures to distinguish between different uranium deposit types, this paper focuses on providing a scientific basis for source identification of materials from different uranium mine sites within a single region, which can then be potentially used within nuclear forensics. A number of different tools, including gamma spectrometry, alpha spectrometry, mineralogy and major and minor elemental analysis, have been utilised to determine the provenance of uranium mineral samples collected at eight mine sites, located within three different uranium provinces, in Portugal. A radiation survey was initially conducted by foot and/or unmanned aerial vehicle at each site to assist sample collection. The results from each mine site were then compared to determine if individual mine sites could be distinguished based on characteristic elemental and isotopic signatures. Gamma and alpha spectrometry were used to differentiate between samples from different sites and also give an indication of past milling and mining activities. Ore samples from the different mine sites were found to be very similar in terms of gangue and uranium mineralogy. However, rarer minerals or specific impurity elements, such as calcium and copper, did permit some separation of the sites examined. In addition, classification rates using linear discriminant analysis were comparable to those in the literature. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.
Uranium accumulation in valentinite within the oxidation zone of an antimony occurrence
International Nuclear Information System (INIS)
Sergeev, I.P.; Kurilo, M.V.
1985-01-01
As a result of mineralogic-radiogeochemical study of real composition of oxidation zone of antimony occurrence represented by quartz - antimonite vien in silicificated sandstones the previousy undescribed phenomenon of uranium concentration in valentinite Sb 2 O 3 one of antimonite oxidation products has been found. According to the data of fission radiography the enrichment of valentinite with uranium is clearly seen, particularly of its concentrically zonal aggregates. The valentinite is the basic uranium mineral-concentrator in the oxidation zone, whereas in the initial mineral - antimonite as well as in the product of its more complete oxidation - stibiconite - uranium is lacking. Probably the crystallochemical properties of anhydrous antimony oxide (valentinite) by analogy with those for iron (goethite hematite) and titanium (leucoxene) are the most favourable for uranium adsorption as compared with high-water antimony oxides (stibiconite) or iron (limonite), which do not usually sorb uranium
Uranium accumulation in valentinite within the oxidation zone of an antimony occurrence
Energy Technology Data Exchange (ETDEWEB)
Sergeev, I.P.; Kurilo, M.V.
1985-01-01
As a result of mineralogic-radiogeochemical study of real composition of oxidation zone of antimony occurrence represented by quartz - antimonite vien in silicificated sandstones the previousy undescribed phenomenon of uranium concentration in valentinite Sb/sub 2/O/sub 3/ one of antimonite oxidation products has been found. According to the data of fission radiography the enrichment of valentinite with uranium is clearly seen, particularly of its concentrically zonal aggregates. The valentinite is the basic uranium mineral-concentrator in the oxidation zone, whereas in the initial mineral - antimonite as well as in the product of its more complete oxidation - stibiconite - uranium is lacking. Probably the crystallochemical properties of anhydrous antimony oxide (valentinite) by analogy with those for iron (goethite hematite) and titanium (leucoxene) are the most favourable for uranium adsorption as compared with high-water antimony oxides (stibiconite) or iron (limonite), which do not usually sorb uranium.
International Nuclear Information System (INIS)
Oliver, Lena; Peterson, Jenny; Wilhelmsen, Katarina
2006-03-01
FOI, has performed a study on uranium conversion processes that are of importance in the production of different uranium compounds in the nuclear industry. The same conversion processes are of interest both when production of nuclear fuel and production of fissile material for nuclear weapons are considered. Countries that have nuclear weapons ambitions, with the intention to produce highly enriched uranium for weapons purposes, need some degree of uranium conversion capability depending on the uranium feed material available. This report describes the processes that are needed from uranium mining and milling to the different conversion processes for converting uranium ore concentrate to uranium hexafluoride. Uranium hexafluoride is the uranium compound used in most enrichment facilities. The processes needed to produce uranium dioxide for use in nuclear fuel and the processes needed to convert different uranium compounds to uranium metal - the form of uranium that is used in a nuclear weapon - are also presented. The production of uranium ore concentrate from uranium ore is included since uranium ore concentrate is the feed material required for a uranium conversion facility. Both the chemistry and principles or the different uranium conversion processes and the equipment needed in the processes are described. Since most of the equipment that is used in a uranium conversion facility is similar to that used in conventional chemical industry, it is difficult to determine if certain equipment is considered for uranium conversion or not. However, the chemical conversion processes where UF 6 and UF 4 are present require equipment that is made of corrosion resistant material
International Nuclear Information System (INIS)
Pin, Patrick; Perot, Bertrand
2013-06-01
This paper reports the experimental qualification of an original uranium characterization method based on fluorescence X rays induced by the spontaneous gamma emission of bituminized radioactive waste drums. The main 661.7 keV gamma ray following the 137 Cs decay produces by Compton scattering in the bituminized matrix an intense photon continuum around 100 keV, i.e. in the uranium X-ray fluorescence region. 'Self-induced' X-rays produced without using an external source allow a quantitative assessment of uranium as 137 Cs and uranium are homogeneously mixed and distributed in the bituminized matrix. The paper presents the experimental qualification of the method with real waste drums, showing a detection limit well below 1 kg of uranium in 20 min acquisitions while the usual gamma rays of 235 U (185 keV) or 238 U (1001 keV of 234m Pa in the radioactive decay chain) are not detected. The relative uncertainty on the uranium mass assessed by self-induced X-ray fluorescence (SXRF) is about 50%, with a 95% confidence level, taking into account the correction of photon attenuation in the waste matrix. This last indeed contains high atomic numbers elements like uranium, but also barium, in quantities which are not known for each drum. Attenuation is estimated thanks to the peak-to-Compton ratio to limit the corresponding uncertainty. The SXRF uranium masses measured in the real drums are in good agreement with long gamma-ray spectroscopy measurements (1001 keV peak) or with radiochemical analyses. (authors)
Machining of uranium and uranium alloys
International Nuclear Information System (INIS)
Morris, T.O.
1981-01-01
Uranium and uranium alloys can be readily machined by conventional methods in the standard machine shop when proper safety and operating techniques are used. Material properties that affect machining processes and recommended machining parameters are discussed. Safety procedures and precautions necessary in machining uranium and uranium alloys are also covered. 30 figures
International Nuclear Information System (INIS)
Mansilla, M.; Dieguez, S.
2014-01-01
The Sierra Pintada uranium district in Mendoza Province, Argentina, was discovered by airborne survey. This deposit is associated with a volcanic caldera and occurs in the Lower Permian volcaniclastic sediments of the Cochico Group, in which aeolian and fluvial sandstones, inter-bedded with ignimbrites, were reworked by pyroclastic flows. The origin of the mineralization is interpreted as a product of the leaching of the inter-bedded rhyolitic tuff. The mineralization is lenticular and nearly concordant with the bedding. The deposit has been affected by a complex fault system, which is responsible for mineralization and disposition via spatial displacement. The primary uranium minerals are uraninite, brannerite and coffinite. Uranophane and low liebigite uranium are the products of the oxidative alteration of primary minerals. This study involves the technical and economical evaluation of the open pit uranium mining project Tigre I – La Terraza in Mendoza, Argentina, at prefeasibility level. Its development includes geological modeling through economic evaluation, and the incorporation of different mining-specific software.
Uranium recovery from slags of metallic uranium
International Nuclear Information System (INIS)
Fornarolo, F.; Frajndlich, E.U.C.; Durazzo, M.
2006-01-01
The Center of the Nuclear Fuel of the Institute of Nuclear Energy Research - IPEN finished the program of attainment of fuel development for research reactors the base of Uranium Scilicet (U 3 Si 2 ) from Hexafluoride of Uranium (UF 6 ) with enrichment 20% in weight of 235 U. In the process of attainment of the league of U 3 Si 2 we have as Uranium intermediate product the metallic one whose attainment generates a slag contend Uranium. The present work shows the results gotten in the process of recovery of Uranium in slags of calcined slags of Uranium metallic. Uranium the metallic one is unstable, pyrophoricity and extremely reactive, whereas the U 3 O 8 is a steady oxide of low chemical reactivity, what it justifies the process of calcination of slags of Uranium metallic. The calcination of the Uranium slag of the metallic one in oxygen presence reduces Uranium metallic the U 3 O 8 . Experiments had been developed varying it of acid for Uranium control and excess, nitric molar concentration gram with regard to the stoichiometric leaching reaction of temperature of the leaching process. The 96,0% income proves the viability of the recovery process of slags of Uranium metallic, adopting it previous calcination of these slags in nitric way with low acid concentration and low temperature of leaching. (author)
Uranium, depleted uranium, biological effects; Uranium, uranium appauvri, effets biologiques
Energy Technology Data Exchange (ETDEWEB)
NONE
2001-07-01
Physicists, chemists and biologists at the CEA are developing scientific programs on the properties and uses of ionizing radiation. Since the CEA was created in 1945, a great deal of research has been carried out on the properties of natural, enriched and depleted uranium in cooperation with university laboratories and CNRS. There is a great deal of available data about uranium; thousands of analyses have been published in international reviews over more than 40 years. This presentation on uranium is a very brief summary of all these studies. (author)
International Nuclear Information System (INIS)
Houston, R.S.; Karlstrom, K.E.
1979-11-01
Uranium has been discovered in fluvial quartz-pebble conglomerates in most of the Precambrian shield areas of the world, including the Canadian, African, South American, Indian, Baltic, and Australian shields. Occurrences in these and other areas are shown. Two of these occurrences, the Huronian supergroup of Canada and the Witwatersrand deposit of South Africa contain 20 to 30 percent of the planet's known uranium reserves. Thus it is critical that we understand the origin of these deposits and develop exploration models that can aid in finding new deposits. Inasmuch as these uranium-bearing conglomerates are confined almost entirely to rocks of Precambrian age, Part I of this review begins with a discussion of Precambrian geology as it applies to the conglomerates. This is followed by a discussion of genetic concepts, a discussion of unresolved problems, and finally a suggested exploration model. Part II summarizes known and potential occurrences of Precambrian fossil placers in the world and evaluates them in terms of the suggested exploration model. Part III discusses the potential for important Precambrian fossil-placer uranium deposits in the United States and includes suggestions that may be helpful in establishing an exploration program in this country. Part III also brings together new (1975-1978) data on uranium occurrences in the Precambrian of the Wyoming Province. Part IV is a complete bibliography of Precambrian fossil placers, divided according to geographical areas. In total, this paper is designed to be a comprehensive review of Precambrian uranium-bearing fossil placers which will be of use to uranium explorationists and to students of Precambrian geology
Energy Technology Data Exchange (ETDEWEB)
Houston, R.S.; Karlstrom, K.E.
1979-11-01
Uranium has been discovered in fluvial quartz-pebble conglomerates in most of the Precambrian shield areas of the world, including the Canadian, African, South American, Indian, Baltic, and Australian shields. Occurrences in these and other areas are shown. Two of these occurrences, the Huronian supergroup of Canada and the Witwatersrand deposit of South Africa contain 20 to 30 percent of the planet's known uranium reserves. Thus it is critical that we understand the origin of these deposits and develop exploration models that can aid in finding new deposits. Inasmuch as these uranium-bearing conglomerates are confined almost entirely to rocks of Precambrian age, Part I of this review begins with a discussion of Precambrian geology as it applies to the conglomerates. This is followed by a discussion of genetic concepts, a discussion of unresolved problems, and finally a suggested exploration model. Part II summarizes known and potential occurrences of Precambrian fossil placers in the world and evaluates them in terms of the suggested exploration model. Part III discusses the potential for important Precambrian fossil-placer uranium deposits in the United States and includes suggestions that may be helpful in establishing an exploration program in this country. Part III also brings together new (1975-1978) data on uranium occurrences in the Precambrian of the Wyoming Province. Part IV is a complete bibliography of Precambrian fossil placers, divided according to geographical areas. In total, this paper is designed to be a comprehensive review of Precambrian uranium-bearing fossil placers which will be of use to uranium explorationists and to students of Precambrian geology.
Methodology and integrated studies for the strategic regional uranium prospects
International Nuclear Information System (INIS)
Andrade Tolentino, J. de.
1984-01-01
An integrated methodology alternative to the traditional one used for uranium prospecting is presented. For this purpose a detailed revision of some methods for finding uranium was made. Then a geological unit located in Minas Gerais, Brazil, was chosen due to its geographical proximity to the Lagoa Real deposit in the Brazilian Bahia State. The methodology applied to this unit gave a preliminary indications of areas to be prospected in detail. 36 refs, 44 figs, 20 tabs
Preliminary report on the geology of the Lakeview uranium area, Lake County, Oregon
International Nuclear Information System (INIS)
Walker, G.W.
1980-01-01
This study was directed partly toward determining uranium resources, but, more specifically toward establishing the geochemical relations of uranium and other metals with rhyolite bodies in the Lakeview uranium area and to compare these bodies with similar rhyolitic bodies outside the area. The ultimate goal of this work was to determine, if possible, the uranium resource potential of these kinds of rocks over an area of several thousand square kilometers and to apply knowledge gained from this resource assessment to similar terranes within the Northern Basin and Range Province. The regional evaluation is still in progress, and its results will be reported at some appropriate time in the future. To these ends a review was made of previous geologic studies of the area and of the uranium deposits themselves, and some regional geologic mapping was done at a scale of 1:24,000. A geologic map was prepared of an area covering about 450 km 2 (approx. 170 mi 2 ), more or less centered on the White King and Lucky Lass mines and on the major cluster of uranium-bearing rhyolites, and some geologic reconnaissance and attendant sampling of rhyolite intrusives and extrusives well outside the Lakeview uranium area were completed. Isotopic dates were obtained on some units and magnetic polarity characteristics were determined on many units in order to more firmly establish age and stratigraphic relations of the diverse volcanic and volcaniclastic units of the region. Major oxide chemistry and selected trace-element chemistry were obtained on those rhyolitic units suitable for analysis in order to establish distribution patterns for uranium, as well as several other metals, in the rhyolitic rocks of the Lakeview uranium area and to make regional correlations with other analyzed rhyolitic rocks
International Nuclear Information System (INIS)
Al-Hamzawi, A.A.; Al-Qadisiyah University, Qadisiyah; Jaafar, M.S.; Tawfiq, N.F.
2015-01-01
The technique of nuclear fission track analysis with solid state nuclear track detectors CR-39 has been applied to determine concentrations of uranium in cancerous samples of human tissues that excised from patients in the three key southern Iraqi governorates namely, Basrah, Dhi-Qar, and Muthanna. These provinces were the sites of intensive military events during the Gulf Wars in 1991 and 2003. The investigation was based on the study of 24 abnormal samples and 12 normal samples for comparing the results. These samples include four types of soft tissues (kidney, breast, stomach and uterus). The results show that uranium concentrations in the normal tissues ranged between (1.42-4.76 μg kg -1 ), whereas in the cancerous tissues ranged between (3.37-7.22 μg kg -1 ). The uranium concentrations in the normal tissues were significantly lower than in the abnormal tissues (P < 0.001). (author)
Phosphorus - uranium mineralization of the Mandacaru Farm, Iraucuba, state of Ceara, Brazil
International Nuclear Information System (INIS)
Leal, J.R.L.V.; Azevedo, L.F. de; Castro, G.L.; Alcantara e Silva, J.R. de
1984-01-01
The phosphorus-uranium mineralization of the Mandacaru Farm (Iraucuba - state of Ceara) is located in the phosphorus-uranium Province of north-central Ceara. The area is a mobile belt placed between the Sao Luiz and the Sao Francisco cratons, related to the Northeast Folding Region. It is represented by lithologies from the Fundamental Complex (Transamazonico Cycle) and the Ceara Group ectinict series (Brasiliano Cycle). All the rocks are cut by Eo-Cambrian acidic dikes and Jurassic basic dikes. The plastic tectonics acted over the regional rocks through four folding phases; the first two being of isoclinal recumbent type, and the last two subvertical open folds. The fissural tectonics affected the area in the form of overthrust faults and transcurrent faults. The fracturing system was reactivated as normal faults during the Brasiliano Cycle. The phosphorus-uranium mineralization appears in the form of uraniferous collophane/apatite forming disseminations i gnaisses, calc-silicated rocks and amphibolites; stockwork structures in marbles; and occurring as matrix in breccias and cataclasites. This mineralization occurs in fractured ad faulted areas, associated to diaphthoresis, sodic metasomatism and episyenitization processes. (Author) [pt
A geological-radiometric uranium survey in the Tlaxiaco area of the State of Oaxaca
International Nuclear Information System (INIS)
Guillen R, O.E.
1981-01-01
Explorations were effected in the northwestern part of the State of Oaxaca neighbouring the city of Tlaxiaco and lying within the Oaxaca-Mixteca province. The survey comprised a regional area of 642.2.K, in which abnormalities auspicious to the presence of mineral uranium had previously been found. The area of interest, initially limited to a strip 10 kilometers long by 1/2 kilometers wide, showed evidence, however, of an even greater extension. Among the lithological units found of predominate interest were clastic, sedimentary rocks, mezozoic carbonate rocks, and extrusive and intrusive igneous rocks. From the high radiometric values obtained, the extrusive pyroclastic rocks showed more favourable signs of the presence of uranium ore and were considered of chief uranium significance in the area. Minerological, structural and lithological detectors (guides) have been set up in the area for an extensive location of abnormalities. The work based on regionally conducted geological and radiological surveys followed by detailed area of interest studies. (author)
In-situ leaching opens new uranium reserves in Texas
International Nuclear Information System (INIS)
White, L.
1975-01-01
A commercial in-situ uranium leaching operation that is quite probably the largest ever built started up in April, 10 mi southwest of George West, Tex. Producing from a pattern of 66 injection wells and 46 extraction wells occupying an area of less than 3 acres, the Clay West mine and plant are expected to reach design capacity of 250,000 lb per year of yellowcake by the end of the summer. By late May, results were sufficiently favorable to make the owners think seriously about an early expansion. Built at a cost of $7 million by joint ventures Atlantic Richfield (50 percent owner and operator), Dalco (25 percent), and US Steel (25 percent), the Clay West mine may be only the first of several mines to extract U 3 O 8 from a uranium province that stretches from north of Houston to Brownsville, at the southernmost tip of the state. Westinghouse subsidiary Wyoming Minerals is building a 250,000-lb-per-year plant near Bruni, with startup planned before the end of 1975, and Mobil Oil is setting up a pilot-scale plant in the same area. A number of other companies are reported to be actively interested in development of in-situ uranium leaching in Texas. (U.S.)
International Nuclear Information System (INIS)
Ma Wenyan; Zhou Chunlin; Han Feng; Di Yuming
2002-01-01
Using the Laser-Fluorescence technique, an investigation was made, adopting the standard mix method, on trace uranium concentrations in hot spring water and geothermal water from Lishan region, and in tap water from some major cities in Shanxi province. Totally 40 samples from 27 sites were investigated. Measurement showed that the tap water contains around 10 -6 g/L of uranium, whose concentrations in both hot spring water and geothermal water are 10 -5 g/L. Most of samples are at normal radioactive background level, some higher contents were determined in a few samples
Possible uranium sources of Streltsovsky uranium ore field
International Nuclear Information System (INIS)
Zhang Lisheng
2005-01-01
The uranium deposit of the Late Jurassic Streltsovaky caldera in Transbaikalia of Russia is the largest uranium field associated with volcanics in the world, its uranium reserves are 280 000 t U, and it is the largest uranium resources in Russia. About one third of the caldera stratigraphic pile consists of strongly-altered rhyolites. Uranium resources of the Streltsovsky caldera are much larger than any other volcanic-related uranium districts in the world. Besides, the efficiency of hydrothermal alteration, uranium resources appear to result from the juxtaposition of two major uranium sources; highly fractionated peralkaline rhyolites of Jurassic age in the caldera, and U-rich subalkaline granites of Variscan age in the basement in which the major uranium-bearing accessory minerals were metamict at the time of the hydrothermal ore formation. (authors)
Process for continuous production of metallic uranium and uranium alloys
Hayden, Jr., Howard W.; Horton, James A.; Elliott, Guy R. B.
1995-01-01
A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO.sub.3), or any other substantially stable uranium oxide, to form the uranium dioxide (UO.sub.2). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl.sub.4), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation.
Process for continuous production of metallic uranium and uranium alloys
Hayden, H.W. Jr.; Horton, J.A.; Elliott, G.R.B.
1995-06-06
A method is described for forming metallic uranium, or a uranium alloy, from uranium oxide in a manner which substantially eliminates the formation of uranium-containing wastes. A source of uranium dioxide is first provided, for example, by reducing uranium trioxide (UO{sub 3}), or any other substantially stable uranium oxide, to form the uranium dioxide (UO{sub 2}). This uranium dioxide is then chlorinated to form uranium tetrachloride (UCl{sub 4}), and the uranium tetrachloride is then reduced to metallic uranium by reacting the uranium chloride with a metal which will form the chloride of the metal. This last step may be carried out in the presence of another metal capable of forming one or more alloys with metallic uranium to thereby lower the melting point of the reduced uranium product. The metal chloride formed during the uranium tetrachloride reduction step may then be reduced in an electrolysis cell to recover and recycle the metal back to the uranium tetrachloride reduction operation and the chlorine gas back to the uranium dioxide chlorination operation. 4 figs.
International Nuclear Information System (INIS)
Bolivar, S.L.
1980-01-01
A Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) for uranium is currently being conducted throughout the conterminous United States and Alaska. The HSSR is part of the National Uranium Resource Evaluation sponsored by the US Department of Energy. This ambitious geochemical reconnaissance program is conducted by four Department of Energy laboratories: Los Alamos Scientific Laboratory, Lawrence Livermore Laboratory, Oak Ridge Gaseous Diffusion Plant, and Savannah River Laboratory. The program is based on an extensive review of world literature, reconnaissance work done in other countries, and pilot studies conducted by each laboratory. Sample-collection methods and sample density are determined to optimize the probability of detecting potential uranium mineralization. To achieve this aim, each laboratory has developed independent standardized field collection procedures that are designed for its section of the country. Field parameters such as pH, conductivity, climate, geography, and geology are recorded at each site. Most areas are sampled at densities of one sample site per 10 to 23 km 2 . The HSSR program has helped to improve existing hydrogeochemical reconnaissance exploration techniques. In addition to providing industry with data that may help to identify potential uranium districts and to extend known uranium provinces, the HSSR also provides multielement analytical data that can be used in water quality, soil, sediment, environmental, and base-metal exploration studies
International Nuclear Information System (INIS)
Bolivar, S.L.
1980-07-01
A Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) for uranium is currently being conducted throughout the conterminous United States and Alaska. The HSSR is part of the National Uranium Resource Evaluation sponsored by the US Department of Energy. This ambitious geochemical reconnasissance program is conducted by four Department of Energy Laboratories: Los Alamos Scientific Laboratory, Lawrence Livermore Laboratory, Oak Ridge Gaseous Diffusion Plant, and Savannah River Laboratory. Each laboratory was assigned a geographic region of the United States. The program is based on an extensive review of world literature, reconnaissance work done in other countries, and pilot studies conducted by each laboratory. Sample-collection methods and sample density are determined to optimize the probability of detecting potential uranium mineralization. To achieve this aim, each laboratory has developed independent standardized field collection procedures that are designed for its section of the country. Field parameters such as pH, conductivity, climate, geography, and geology are recorded at each site. Most areas are sampled at densities of one sample site per 10 to 23 km 2 . The HSSR program has helped to improve existing hydrogeochemical reconnaissance exploration techniques. In addition to providing industry with data that may help to identify potential uranium districts and to extend known uranium provinces, the HSSR also provides multielement analytical data that can be used in water quality, soil, sediment, environmental, and base-metal exploration studies
International Nuclear Information System (INIS)
Navarra, P.R.; Benitez, A.F.
1997-01-01
In the future the uranium exploration activities of CNEA would tend to improve the knowledge of geology and uranium favorability; to perform prospection tasks, and research and development in exploration technologies, to contribute to be in a position to meet the requirements of the country in the long term. On the other hand, a strong growth of nuclear capacity is expected in the first two decades of the next century. Based on its promising grade, the Cerro Solo uranium ore deposit was selected in 1990 by the CNEA to carry out an assessment project. The intensive exploration level was accomplished, as follows: definition of general characteristics of the main orebodies; detailed geologic studies; estimation of resources with adequate data; and preliminary selection of mining-milling methods to estimate the potential profitability of the project. The deposit belongs to the sandstone type. The mineralized layers are distributed into the fluvial sandstones and conglomerates of the cretaceous Chubut Group, lying 50 to 130 m deep Resources of the deposit, with an average grade of 0.3% U, in tonnes of recoverable uranium at costs of up to $80/kg U, are: Reasonable Assured Resources (RAR): 800 t U, Estimated Additional Resources, Category I (EAR-I): 2100 t U. Follow-up drilling programmes are being performed at present in some of the target sites defined in the paleochannel that hosts the Cerro Solo deposit, in order to establish the hypothetical resources of the area. The sites were determined as a result of the exploration that CNEA conducted in the Pichinan uranium district. Recently a regional research project was formulated, for the detailed exploration in the San Jorge Gulf Basin, where the Chubut Group is distributed. 17 refs, 4 figs
International Nuclear Information System (INIS)
Wu Jiguang
2011-01-01
The element characteristic of Indo-Chinese epoch Xiazhuang granite is rich in silicon (SiO 2 =69.13%∼73.39%), alkalis (K 2 O+Na 2 O=7.49%∼8.69%), the ASI=1.01∼1.21 and ratio of w (K 2 O)/w (Na 2 O)>1, Xiazhuang pluton is belong to high potassium calcium-alkaline and aluminous series rocks. It shows that the pluton is typical S-type granite, little part is A-type granite character. Under the extension tectonic setting of lithosphere, the Xiazhuang pluton is partial melting product that making up metamorphic mud and sandstone together. By analysing the tectonic setting,the pluton is belong to post-collision granite that original rock provide abundant of uranium content for granite and the tectonic setting of forming provide the moving channels and occurrence space for uranium deposit. (authors)
Depleted uranium. A post-war disaster for environment and health
International Nuclear Information System (INIS)
Diehl, P.; Fahey, D.; Bertell, R.; Robicheau, D.; Bristow, R.; Arbuthnot, F.; Van der Keur, H.
1999-05-01
In the course of the preparations for the The Hague Appeal for Peace '99 conference in the Netherlands, Laka decided to make a brochure about the use of depleted uranium in conventional weaponry and its consequences. The idea was born because of the short time reserved during the session for the presentation of all details about depleted uranium (DU). Although the word 'depleted uranium' may suggest no harmful impact from radiation, this brochure will clarify the real radiotoxic (and chemotoxic) properties of DU. Laka asked several 'insiders' to take part in the completion of the brochure. Thanks to their efforts, we have been able to present well-documented articles for activists, scientists, scholars and students to share with them valuable information about the hazardous impact of DU contamination and its consequences on human health and the environment. Taking notice of the growing military use of DU, we must consider not only the increased threats of radioactive battlefields but also the whole dirty cycle in the uranium industry connected with the DU technology and its impact on health and the environment in the surroundings of test areas and in the uranium industry itself. The contents of all the contributions are under the responsibility of the authors.The titles of the contributions are (1) Depleted uranium. A by-product of the nuclear chain; (2) Depleted uranium weapons. Lessons from the 1991 Gulf War; (3) Gulf War veterans and depleted uranium; (4) The next testing site for depleted uranium weaponry; (5) Depleted uranium. The thoughts of the first British Gulf War veteran to be tested for, and found to be poisoned with depleted uranium; (6) The health of the Iraqi people; (7) Uranium pollution from the amsterdam 1992 plane crash; and (8) an overview od organizations involved in campaigns against depleted uranium. refs
International Nuclear Information System (INIS)
Benitez, A.F.; Fuente, A.; Maloberti, A.; Landi, V.A.; Bianchi, R.E.; Marveggio de Bianchi, N.; Gayone, M.R.
1993-01-01
The Cerro Solo uranium ore deposit, is located 420 km west from Trelew city, Chubut province, in the extra-andean. The geologic environment belongs to the northwest edge portion of the intracratonic San Jorge Gulf Basin. The uraniferous district is named Pichinanes Ridge district. The mineralization lies 25 to 130 m depth, and is hosted by Los Adobes formation aged Aptian-Albian, made up by conglomerates, sandstones, coarse-sandstones and less abundant siltstones and claystones. The Cerro Solo ore deposit that belongs to the sandstone type-uranium occurrences are lenticular or tabular shaped, associated with organic material and pyrite, generally roughly parallel to the bedding (Trend-Type). The uranium minerals are uraninite and coffinite associated with organic material and pyrite, and frequently hematite, goethite, calcite, siderite and barite are observed. (Author)
International Nuclear Information System (INIS)
An Zhengchang; Luo Xiaoqiang
2010-01-01
Late Paleozoic volcanic rocks in Beishan area are the favorable constructions of hydrothermal type and volcanic type deposit. From the distribution of volcanic rocks, the volcanic compositions, the volcanic facies, volcanic eruption method and rhythm, chemical and trace elements compositions, and so on, it discusses the characteristics of the Late Devonian volcanic construction in this area and its relationship with uranium mineralization, analyzes the role of volcanic ore-control mechanism, and summarizes uranium ore forming regularity of volcanic construction in Late Paleozoic. (authors)
Distribution of uranium in dental porcelains by means of the fission track method
International Nuclear Information System (INIS)
Shimizu, Masami; Noguchi, Kunikazu; Moriwaki, Kazunari; Sairenji, Eiko
1980-01-01
Porcelain teeth, some of which contain uranium compounds for aesthetic purpose, have been widely used in dental clinics. Hazardous effects due to uranium radiation have been suggested by recent publications. In the previous study, the authors reported the uranium content of porcelain teeth and radiation dose by it. In this study, using the fission track method, the authors examined spatial distribution of uranium in dental porcelain teeth (4 brands) which were marketed in Japan. From each sample of porcelain tooth, a 1-mm-thick specimen was sliced, and uranium content was measured at every 0.19 mm from labial side to lingual side for making a uranium distribution chart. Higher uranium concentration was found in Trubyte Bioblend porcelain teeth (USA) and they showed almost uniform distribution of uranium, while those of the Japanese three brands indicated, in most case, comparatively lower concentration and found to be non-uniform distributions. Range of uranium concentration in these brands were N.D. -- 5.2 ppm (Shofu-Ace), N.D. -- 342 ppm (Shofu-Real), N.D. -- 47 ppm (G.C. Livdent) and N.D. -- 235 ppm (Trubyte Bioblend), respectively. (author)
International Nuclear Information System (INIS)
Fenton, B.R.; Waite, T.D.
1996-01-01
The uptake of U(VI) as UO 2+ 2 on a natural complex mineral assemblage has been studied using batch selective chemical extraction techniques and secondary ion mass spectroscopy (SIMS). Sediments used in the study consisted of a quartz/mica schist collected from the locale of the Koongarra Uranium ore body, Alligator Rivers Uranium Province, Northern Territory, Australia. The bulk sediment was gravity separated into four size fractions, with attention focused on the nominally <25 μm and 250-1000 μm fractions of the bulk sample, in order to assess the effects of particle size on uranium uptake. Investigation of the kinetics of elemental release in the presence of selective extractants show that uranium is bound largely within the iron and aluminium oxyhydroxides of the assemblage, with a highly mobile fraction of this associated with aluminol sites. SIMS analysis of the natural substrate confirms that significant quantities of aluminium are present in surface layers. The effect of particle size on the uptake of uranium indicates very little change with respect to particle size. This finding may be attributed to the presence of highly porous surface coatings. (orig.)
Martini, Giorgio; Paffumi, Elena; De Gennaro, Michele; Mellios, Giorgos
2014-07-15
This paper presents an evaluation of the European type-approval test procedure for evaporative emissions from passenger cars based on real-world mobility data. The study relies on two large databases of driving patterns from conventional fuel vehicles collected by means of on-board GPS systems in the Italian provinces of Modena and Firenze. Approximately 28,000 vehicles were monitored, corresponding to approximately 36 million kilometres over a period of one month. The driving pattern of each vehicle was processed to derive the relation between trip length and parking duration, and the rate of occurrence of parking events against multiple evaporative cycles, defined on the basis of the type-approval test procedure as 12-hour diurnal time windows. These results are used as input for an emission simulation model, which calculates the total evaporative emissions given the characteristics of the evaporative emission control system of the vehicle and the ambient temperature conditions. The results suggest that the evaporative emission control system, fitted to the vehicles from Euro 3 step and optimised for the current type-approval test procedure, could not efficiently work under real-world conditions, resulting in evaporative emissions well above the type-approval limit, especially for small size vehicles and warm climate conditions. This calls for a revision of the type-approval test procedure in order to address real-world evaporative emissions. Copyright © 2014. Published by Elsevier B.V.
Recovery of uranium from crude uranium tetrafluoride
Energy Technology Data Exchange (ETDEWEB)
Ghosh, S K; Bellary, M P; Keni, V S [Chemical Engineering Division, Bhabha Atomic Research Centre, Mumbai (India)
1994-06-01
An innovative process has been developed for recovery of uranium from crude uranium tetrafluoride cake. The process is based on direct dissolution of uranium tetrafluoride in nitric acid in presence of aluminium hydroxide and use of solvent extraction for removal of fluorides and other bulk impurities to make uranium amenable for refining. It is a simple process requiring minimum process step and has advantage of lesser plant corrosion. This process can be applied for processing of uranium tetrafluoride generated from various sources like uranium by-product during thorium recovery from thorium concentrate, first stage product of uranium recovery from phosphoric acid by OPPA process and off grade uranium tetrafluoride material. The paper describes the details of the process developed and demonstrated on bench and pilot scale and its subsequent modification arising out of bulky solid waste generation. The modified process uses a lower quantity of aluminium hydroxide by allowing a lower dissolution of uranium per cycle and recycles the undissolved material to the next cycle, maintaining the overall recovery at high level. This innovation has reduced the solid waste generated by a factor of four at the cost of a slightly larger dissolution vessel and its increased corrosion rate. (author). 4 refs., 1 fig., 3 tabs.
Recovery of uranium from crude uranium tetrafluoride
International Nuclear Information System (INIS)
Ghosh, S.K.; Bellary, M.P.; Keni, V.S.
1994-01-01
An innovative process has been developed for recovery of uranium from crude uranium tetrafluoride cake. The process is based on direct dissolution of uranium tetrafluoride in nitric acid in presence of aluminium hydroxide and use of solvent extraction for removal of fluorides and other bulk impurities to make uranium amenable for refining. It is a simple process requiring minimum process step and has advantage of lesser plant corrosion. This process can be applied for processing of uranium tetrafluoride generated from various sources like uranium by-product during thorium recovery from thorium concentrate, first stage product of uranium recovery from phosphoric acid by OPPA process and off grade uranium tetrafluoride material. The paper describes the details of the process developed and demonstrated on bench and pilot scale and its subsequent modification arising out of bulky solid waste generation. The modified process uses a lower quantity of aluminium hydroxide by allowing a lower dissolution of uranium per cycle and recycles the undissolved material to the next cycle, maintaining the overall recovery at high level. This innovation has reduced the solid waste generated by a factor of four at the cost of a slightly larger dissolution vessel and its increased corrosion rate. (author)
The uranium potential of the continental Cretaceous of Patagonia
International Nuclear Information System (INIS)
Olsen, H.; Berizzo, J.
1980-01-01
The geological features of the fluvial sedimentation of the Cretaceous of Patagonia - the Grupo Chubut Formation in the provinces of Chubut and Santa Cruz, underlined this environment as one of high favourability for discovering uranium deposits. The area has been explored by the CNEA who found two outstanding levels of fluvial sediments that are today the target of further studies to find new deposits. The general geological features are given, together with the results of the exploration up to date, distribution of radiometric anomalies, deposits discovered and an estimation of the uraniferous potential of the Formation. (author)
Chronicle on the Malargue uranium plant
International Nuclear Information System (INIS)
Gregui, Jose E.
2009-01-01
After the Second World War all countries that had industrial development programs, began their works in the nuclear field: if they would achieve satisfactory results depend on their scientific and technological level and on the political choices. Argentina was among those nations that had an industrial development program and very early began a series of actions in the area that at the same time was called 'atomic energy'. Uranium was the basic requirement to design a nuclear program. As a result of the first studies undertaken in the country several uraniferous deposits were discovered. The most important discovery was on May 31, 1952: the Huemul Reservoir located 40 km south of Malargue in the province of Mendoza. The site marks the beginning of the story. (author) [es
Radioactivity Risk Assessment of Radon and Gamma Dose at One Uranium Tailings Pond in China
Lou, Yalong; Liu, Yong; Peng, Guowen; Zhao, Guodong; Zhang, Yan; Yang, Zhu
2018-01-01
A year-long monitoring of gamma radiation effective dose rate and radon concentration had been done in the reservoir area of one uranium tailings pond in Hunan province (The monitoring area included indoor and outdoor area of residential buildings and workshops, tailings dam slope). Afterwards, the annual effective radiation dose of the people in that radiation environment had been calculated based on the results of monitoring, as well as a radiation risk assessment. According to the assessment, gamma radiation effective dose rate and radon concentration in the monitoring area were low, and the annual effective radiation dose was far below the international standard (30mSv), which showed that the radiation would not put the people’s health at risk. However, the annual effective radiation dose of gamma was far above that of radon in the area of uranium tailings pond; therefore, it’s advisable to take quarantine measures in in the area of uranium tailings pond to keep the surrounding residents away from unnecessary ionizing radiation.
International Nuclear Information System (INIS)
Van Eeckhout, E.M.
1980-12-01
Some 1370 water and 1951 sediment samples were collected from 1994 locations in the Butte quadrangle, Montana, in 1976 and 1977 by the University of Montana for the Los Alamos Scientific Laboratory (LASL). The LASL analyzed the water samples for uranium and the sediment samples for uranium plus 42 additional elements. The data were then released to the Montana College of Mineral Science and Technology (MCMS and T), which was responsible for the evaluation of the uranium data. The data have subsequently been released by the LASL in an open-file report (Broxton, 1980). Statistical evaluations of the data were undertaken for uranium, copper, lead, zinc, manganese, gold, and silver. The uranium evaluations indicated certain areas in the western part of the quadrangle to be favorable for further investigation (particularly along the Rock Creek), as well as anomalous areas just north of Anaconda. The entire Boulder Batholith area had a high uranium background, but there didn't appear to be any particular site in this area that might be worth pursuing. The multielement evaluations confirmed the known base and precious metal provinces within the quadrangle. A methodology for evaluating data tapes from the National Uranium Resource Evaluation (NURE) program was developed and presented throughout this report. This methodology could be developed further to define areas worth exploring for commodities other than uranium
Analytical method of uranium (IV) and uranium (VI) in uranium ores and uranium-bearing rocks
International Nuclear Information System (INIS)
Shen Zhuqin; Zheng Yongfeng; Li Qingzhen; Zhong Miaolan; Gu Dingxiang
1995-11-01
The best conditions for keeping the original valences of uranium during the dissolution and separation procedure of geological samples (especially those micro uranium-bearing rock) were studied. With the exist of high concentration protectants, the sample was decomposed with concentration HF at 40 +- 5 degree C. The U(VI) was dissolved completely and formed stable complex UO 2 F 2 , the U(IV) was precipitated rapidly and carried by carrier. Quantitative separation was carried out immediately with suction. The decomposition of sample and separation of solid/liquid phases was completed within two minutes. After separation, the U(IV) and U(VI) were determined quantitatively with laser fluorescence or voltametry respectively according to the uranium content. The limit of detection for this method is 0.7 μg/g, RSD is 10.5%, the determinate range of uranium is 2 x 10 -6 ∼10 -1 g/g. The uranium contents and their valence state ratio were measured for more than one hundred samples of sand stone and granite, the accuracy and precision of these results are satisfactory for uranium geological research. (12 tabs.; 11 refs.)
Reduction of uranium hexafluoride to uranium tetrafluoride
International Nuclear Information System (INIS)
Chang, I.S.; Do, J.B.; Choi, Y.D.; Park, M.H.; Yun, H.H.; Kim, E.H.; Kim, Y.W.
1982-01-01
The single step continuous reduction of uranium hexafluoride (UF 6 ) to uranium tetrafluoride (UF 4 ) has been investigated. Heat required to initiate and maintain the reaction in the reactor is supplied by the highly exothermic reaction of hydrogen with a small amount of elemental fluorine which is added to the uranium hexafluoride stream. When gases uranium hexafluoride and hydrogen react in a vertical monel pipe reactor, the green product, UF 4 has 2.5g/cc in bulk density and is partly contaminated by incomplete reduction products (UF 5 ,U 2 F 9 ) and the corrosion product, presumably, of monel pipe of the reactor itself, but its assay (93% of UF 4 ) is acceptable for the preparation of uranium metal with magnesium metal. Remaining problems are the handling of uranium hexafluoride, which is easily clogging the flowmeter and gas feeding lines because of extreme sensitivity toward moisture, and a development of gas nozzel for free flow of uranium hexafluoride gas. (Author)
Precise coulometric titration of uranium in a high-purity uranium metal and in uranium compounds
International Nuclear Information System (INIS)
Tanaka, Tatsuhiko; Yoshimori, Takayoshi
1975-01-01
Uranium in uranyl nitrate, uranium trioxide and a high-purity uranium metal was assayed by the coulometric titration with biamperometric end-point detection. Uranium (VI) was reduced to uranium (IV) by solid bismuth amalgam in 5M sulfuric acid solution. The reduced uranium was reoxidized to uranium (VI) with a large excess of ferric ion at a room temperature, and the ferrous ion produced was titrated with the electrogenerated manganese(III) fluoride. In the analyses of uranium nitrate and uranium trioxide, the results were precise enough when the error from uncertainty in water content in the samples was considered. The standard sample of pure uranium metal (JAERI-U4) was assayed by the proposed method. The sample was cut into small chips of about 0.2g. Oxides on the metal surface were removed by the procedure shown by National Bureau of Standards just before weighing. The mean assay value of eleven determinations corrected for 3ppm of iron was (99.998+-0.012) % (the 95% confidence interval for the mean), with a standard deviation of 0.018%. The proposed coulometric method is simple and permits accurate and precise determination of uranium which is matrix constituent in a sample. (auth.)
31 CFR 540.317 - Uranium feed; natural uranium feed.
2010-07-01
... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Uranium feed; natural uranium feed... (Continued) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.317 Uranium feed; natural uranium feed. The...
International Nuclear Information System (INIS)
De Voto, R.H.
1984-01-01
This paper is a review of the methodology and technology that are currently being used in varying degrees in uranium exploration activities worldwide. Since uranium is ubiquitous and occurs in trace amounts (0.2 to 5 ppm) in virtually all rocks of the crust of the earth, exploration for uranium is essentially the search of geologic environments in which geologic processes have produced unusual concentrations of uranium. Since the level of concentration of uranium of economic interest is dependent on the present and future price of uranium, it is appropriate here to review briefly the economic realities of uranium-fueled power generation. (author)
International Nuclear Information System (INIS)
1982-01-01
The development, prospecting, research, processing and marketing of South Africa's uranium industry and the national policies surrounding this industry form the headlines of this work. The geology of South Africa's uranium occurences and their positions, the processes used in the extraction of South Africa's uranium and the utilisation of uranium for power production as represented by the Koeberg nuclear power station near Cape Town are included in this publication
Influence of uranium hydride oxidation on uranium metal behaviour
International Nuclear Information System (INIS)
Patel, N.; Hambley, D.; Clarke, S.A.; Simpson, K.
2013-01-01
This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)
Influence of uranium hydride oxidation on uranium metal behaviour
Energy Technology Data Exchange (ETDEWEB)
Patel, N.; Hambley, D. [National Nuclear Laboratory (United Kingdom); Clarke, S.A. [Sellafield Ltd (United Kingdom); Simpson, K.
2013-07-01
This work addresses concerns that the rapid, exothermic oxidation of active uranium hydride in air could stimulate an exothermic reaction (burning) involving any adjacent uranium metal, so as to increase the potential hazard arising from a hydride reaction. The effect of the thermal reaction of active uranium hydride, especially in contact with uranium metal, does not increase in proportion with hydride mass, particularly when considering large quantities of hydride. Whether uranium metal continues to burn in the long term is a function of the uranium metal and its surroundings. The source of the initial heat input to the uranium, if sufficient to cause ignition, is not important. Sustained burning of uranium requires the rate of heat generation to be sufficient to offset the total rate of heat loss so as to maintain an elevated temperature. For dense uranium, this is very difficult to achieve in naturally occurring circumstances. Areas of the uranium surface can lose heat but not generate heat. Heat can be lost by conduction, through contact with other materials, and by convection and radiation, e.g. from areas where the uranium surface is covered with a layer of oxidised material, such as burned-out hydride or from fuel cladding. These rates of heat loss are highly significant in relation to the rate of heat generation by sustained oxidation of uranium in air. Finite volume modelling has been used to examine the behaviour of a magnesium-clad uranium metal fuel element within a bottle surrounded by other un-bottled fuel elements. In the event that the bottle is breached, suddenly, in air, it can be concluded that the bulk uranium metal oxidation reaction will not reach a self-sustaining level and the mass of uranium oxidised will likely to be small in relation to mass of uranium hydride oxidised. (authors)
Correlation of uranium geology between South America and Africa
International Nuclear Information System (INIS)
1986-01-01
Acting upon the recommendation of an Advisory Group Meeting held in 1980, the IAEA organized a Working Group on the Correlation of the Uranium Geology between South America and Africa because of the tremendous geological potential for uranium and the interest showed by the Member States of the regions concerned. The report of this Working Group is now presented. The aim of this report is to provide the nuclear industry and, in particular, the countries of the region with a broad but updated outline of current development in the uranium geology and the uranium potential of Africa and South America. The scope is such that it will provide, for those not directly involved in uranium exploration in the area, a general technical summary on the regional geology and tectonics of these two continents in order that the geodynamic setting of their uranium occurrences may be correlated. With respect to the area to be covered and bearing in mind the purpose of this study, the Working Group surveyed the most relevant parts of western Gondwanaland, of which the two continents form a part. The area covered by the report extends from north of the West African Craton and the Guiana Shield to the southern end of South America and Africa; from the Amazonian Province in western Brazil and western Argentina to the central part of the West African Craton, Congo-Kasai Craton. The Andean Chain in South America and the Atlas Mountains in North Africa, which were formed by continental accretion in recent geological time and post-dated the split and drift of the two land masses, were not considered. Some of the inner portions of those cratons distant from the coastlines and for which the correlation features do not apply have also been omitted. However, certain areas of important uranium mineralization outside the main study area have been described in order to offer comparative models for future exploration elsewhere. The subject of the report is discussed under six headings: cratonic areas
International Nuclear Information System (INIS)
Brockmann, Sina
2013-01-01
For risk assessment of anthropogenic uranium contaminations in the environment a detailed knowledge of the migration and immobilization behavior is required to prevent health hazards for humans and animals caused by an uncontrolled discharge of uranium. Hence, comprehensive studies on the interactions of uranium with the environment are required. Besides the influences of the geological materials, there is a huge effect of the biosphere, especially the interactions with microorganisms and biofilms, on the properties of uranium in the environment. The aim of this study was to investigate and to describe naturally occurring biofilms from real uranium contaminated areas and their influence on the uranium migration. The investigations in this study on the localization and the speciation of the uranium in the biosystems were primarily done with a coupled system of laser scanning microscopy (CLSM) and laser induced fluorescence spectroscopy (LIFS). Natural biofilms collected from two uranium contaminated acid mine drainage (AMD) environments, the former uranium mine in Koenigstein (Saxony, Germany) and the former Gessenheap near Ronneburg (Thuringia,Germany), were investigated in this study. The chosen samples represent typical biofilm communities living in AMD water and are exemplary for potentially occurring scenarios of contaminated mining water both in the underground and on the surface. The investigation on the interactions between uranium and Euglena mutabilis, which is a typical unicellular microorganism that can be found in acidic, uranium and other heavy metal containing waters, was another important part of this study. Bioaccumulation experiments of uranium on living Euglena mutabilis cells depending on the pH (pH 3 - 6) and on the background media in sodium perchlorate (9 g/l) or sodium sulfate (3.48 g/l) solution containing 0.01 mM uranium show an effective immobilization of uranium. At the acidic pH-values (pH 3 - 4) over 90 % of the added uranium was
Uranium conversion; Urankonvertering
Energy Technology Data Exchange (ETDEWEB)
Oliver, Lena; Peterson, Jenny; Wilhelmsen, Katarina [Swedish Defence Research Agency (FOI), Stockholm (Sweden)
2006-03-15
FOI, has performed a study on uranium conversion processes that are of importance in the production of different uranium compounds in the nuclear industry. The same conversion processes are of interest both when production of nuclear fuel and production of fissile material for nuclear weapons are considered. Countries that have nuclear weapons ambitions, with the intention to produce highly enriched uranium for weapons purposes, need some degree of uranium conversion capability depending on the uranium feed material available. This report describes the processes that are needed from uranium mining and milling to the different conversion processes for converting uranium ore concentrate to uranium hexafluoride. Uranium hexafluoride is the uranium compound used in most enrichment facilities. The processes needed to produce uranium dioxide for use in nuclear fuel and the processes needed to convert different uranium compounds to uranium metal - the form of uranium that is used in a nuclear weapon - are also presented. The production of uranium ore concentrate from uranium ore is included since uranium ore concentrate is the feed material required for a uranium conversion facility. Both the chemistry and principles or the different uranium conversion processes and the equipment needed in the processes are described. Since most of the equipment that is used in a uranium conversion facility is similar to that used in conventional chemical industry, it is difficult to determine if certain equipment is considered for uranium conversion or not. However, the chemical conversion processes where UF{sub 6} and UF{sub 4} are present require equipment that is made of corrosion resistant material.
International Nuclear Information System (INIS)
Airey, P.L.; Roman, D.; Golian, C.; Short, S.; Nightingale, T.; Lowson, R.T.; Davey, B.G.; Gray, D.
1984-01-01
Appropriate geochemical analogues may be used to reduce the uncertainties in predicting the long-term transport of actinides, radium and fission products from laboratory adsorption and hydrological data. In this study the migration of uranium series nuclides within, and down-gradient of ore bodies in the Alligator Rivers uranium province of the Northern Territory of Australia is described. A mathematical framework was developed to permit calculation of the rate of leaching or deposition of uranium and radium between defined zones of the ore bodies, and the rate of loss of the nuclides due to groundwater transport and surface erosion. A detailed study was made of the distribution of uranium, thorium and radium isotopes within various minerals comprising the weathered ore assemblage. Uranium and thorium concentrate principally in the iron minerals and radium in the clay-quartz phases. Substantial disequilibria are observed, which are attributed to a combination of α-recoil and chemical effects. Evidence of the relative lability of iron phases is presented. The transport of uranium series nuclides in groundwater intersecting the deposits was investigated. Down-gradient of the Ranger One deposit, the maximum retardation factor of uranium is 250. The role of colloids in groundwater transport is being studied. Uranium is transported principally in solution. There appears to be an equilibrium between solute and articulate uranium
Energy Technology Data Exchange (ETDEWEB)
Scislewski, Alexandro Rocha
2004-01-15
In the present research, the proposal was to develop a preliminary study about the geochemical behavior of determined chemical elements, mainly the uranium, during the action of weathering processes in the rocks that bear the uranium mineralizations of the Caetite-Lagoa Real region, State of Bahia, more specifically of the Jazida Cachoeira uranium mine. To reach this purpose were used samples that represent several stages of the milling process of the uranium ore, so selecting representatives of the host rock, the ore and the treated ore (waste from the milling plant) to be used in the laboratory-controlled experiments. The samples were dried, sieved and finally introduced in the reactors, these adapted from the Flow-Through Reactor of Brantley and Chen. In the geochemical point of view, the results of the experiments showed a distinct behavior between the samples. It was observed that the treated ore, in relation to the host rocks of the ore and the own ore, shown a faster and homogeneous interaction with the leaching solution; it was also noted that in the output solution of the treated ore samples existed a significant complexation of the uranium by the sulfate (S0{sub 4}{sup -2}), ), instead of the non treated samples (host rock and ore) that were complexed mainly by the carbonate (C0{sub 3}{sup -2}). These different results are attributed to the alterations imposed to the rock during the milling process, and occur mainly, during the acid attack in the leaching process of the milling plant. The results and conclusions of this research, in spite of been preliminary, are essential to understand the behavior of the geochemical speciation of the effluent solutions; to understand the alterations of a rock matrix, and finally, to understand the migration chemical behavior of the related chemical elements. It is expected that these results contribute, in the future, to a deeper knowledge of the processes that control the chemical composition of the natural waters from
Energy Technology Data Exchange (ETDEWEB)
Moreau, M [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires
1960-07-01
In Madagascar, the first typical occurrences of thorium and uranium are about 500 million years old. Previously thorium and uranium were rather concentrated in the granitic and charnockitic zones, chiefly in minerals such as monazite, apatite and zircon. At the end of the Precambrian period, metasomatic granites occur especially in the anticlinal series (Andriba orthite granite). The granitization is followed by the formation of the main pegmatitic areas in the Island with Th-U niobotantalates, uraninite and beryl. The pegmatites are well developed in the synclinal series with a poor migmatization or no migmatization at all. In the same time a large uranium and thorium province with uranothorianite deposits appears within the calcomagnesian series of the Southern part of Madagascar. Later, large amounts of monazite were carried down to the detritic Karroo sediments during tile erosion of the metamorphic precambrian rocks. Monazite has been concentrated again by frequent marine incursions, till the present time. In the medium Karroo, near Folakara, uranium minerals occur in direct relation with carbonaceous material. Finally we must note the uranium occurrence in the pleistocene carbonaceous shales of Antsirabe basin, in contact with crystalline rocks. (author) [French] A Madagascar, le premier cycle uranifere et thorifere bien caracterise se situe aux alentours de 500 millions d'annees. Auparavant, le thorium et l'uranium sont concentres de preference dans les zones granitiques et charnockites sous forme de monazite, apatite ou zircon. Vers la fin du Precambrien, se produisent des granitisations metasomatiques, surtout dans les zones anticlinales (type Andriba a orthite). La fin de cette granitisation s'accompagne de la formation des principaux champs pegmatitiques de l'Ile a niobotantalates uraniferes, uraninite et beryl, qui se developpent de preference dans les series synclinales peu ou pas migmatisees. A cette meme epoque s'individualise au sein des series
International Nuclear Information System (INIS)
Mackay, G.A.
1978-01-01
The author discusses the contribution made by various energy sources in the production of electricity. Estimates are made of the future nuclear contribution, the future demand for uranium and future sales of Australian uranium. Nuclear power growth in the United States, Japan and Western Europe is discussed. The present status of the six major Australian uranium deposits (Ranger, Jabiluka, Nabarlek, Koongarra, Yeelerrie and Beverley) is given. Australian legislation relevant to the uranium mining industry is also outlined
International Nuclear Information System (INIS)
Pluskal, O.
1992-01-01
Data and knowledge related to the prospecting, mining, processing and export of uranium ores in Czechoslovakia are presented. In the years between 1945 and January 1, 1991, 98,461.1 t of uranium were extracted. In the period 1965-1990 the uranium industry was subsidized from the state budget to a total of 38.5 billion CSK. The subsidies were put into extraction, investments and geologic prospecting; the latter was at first, ie. till 1960 financed by the former USSR, later on the two parties shared costs on a 1:1 basis. Since 1981 the prospecting has been entirely financed from the Czechoslovak state budget. On Czechoslovak territory uranium has been extracted from deposits which may be classified as vein-type deposits, deposits in uranium-bearing sandstones and deposits connected with weathering processes. The future of mining, however, is almost exclusively being connected with deposits in uranium-bearing sandstones. A brief description and characteristic is given of all uranium deposits on Czechoslovak territory, and the organization of uranium mining in Czechoslovakia is described as is the approach used in the world to evaluate uranium deposits; uranium prices and actual resources are also given. (Z.S.) 3 figs
Uranium in Niger; L'uranium au Niger
Energy Technology Data Exchange (ETDEWEB)
Gabelmann, E
1978-03-15
This document presents government policy in the enhancement of uranium resources, existing mining companies and their productions, exploitation projects and economical outcome related to the uranium mining and auxiliary activities. [French] Le document presente la politique de l'Etat dans le cadre de la mise en valeur des ressources d'uranium, les societes minieres existantes et leurs productions, les projets d'exploitation d'uranium et les retombees economiques liees aux activites uraniferes et connexes.
Van Gosen, Bradley S.; Hall, Susan M.
2017-12-18
This report describes the discovery and geology of two near-surface uranium deposits within calcareous lacustrine strata of Pleistocene age in west Texas, United States. Calcrete uranium deposits have not been previously reported in the United States. The west Texas uranium deposits share characteristics with some calcrete uranium deposits in Western Australia—uranium-vanadium minerals hosted by nonpedogenic calcretes deposited in saline lacustrine environments.In the mid-1970s, Kerr-McGee Corporation conducted a regional uranium exploration program in the Southern High Plains province of the United States, which led to the discovery of two shallow uranium deposits (that were not publicly reported). With extensive drilling, Kerr-McGee delineated one deposit of about 2.1 million metric tons of ore with an average grade of 0.037 percent U3O8 and another deposit of about 0.93 million metric tons of ore averaging 0.047 percent U3O8.The west-Texas calcrete uranium-vanadium deposits occur in calcareous, fine-grained sediments interpreted to be deposited in saline lakes formed during dry interglacial periods of the Pleistocene. The lakes were associated with drainages upstream of a large Pleistocene lake. Age determinations of tephra in strata adjacent to one deposit indicate the host strata is middle Pleistocene in age.Examination of the uranium-vanadium mineralization by scanning-electron microscopy indicated at least two generations of uranium-vanadium deposition in the lacustrine strata identified as carnotite and a strontium-uranium-vanadium mineral. Preliminary uranium-series results indicate a two-component system in the host calcrete, with early lacustrine carbonate that was deposited (or recrystallized) about 190 kilo-annum, followed much later by carnotite-rich crusts and strontium-uranium-vanadium mineralization in the Holocene (about 5 kilo-annum). Differences in initial 234U/238U activity ratios indicate two separate, distinct fluid sources.
International Nuclear Information System (INIS)
Poty, B.; Roux, J.
1998-01-01
The processing of uranium ores for uranium extraction and concentration is not much different than the processing of other metallic ores. However, thanks to its radioactive property, the prospecting of uranium ores can be performed using geophysical methods. Surface and sub-surface detection methods are a combination of radioactive measurement methods (radium, radon etc..) and classical mining and petroleum prospecting methods. Worldwide uranium prospecting has been more or less active during the last 50 years, but the rise of raw material and energy prices between 1970 and 1980 has incited several countries to develop their nuclear industry in order to diversify their resources and improve their energy independence. The result is a considerable increase of nuclear fuels demand between 1980 and 1990. This paper describes successively: the uranium prospecting methods (direct, indirect and methodology), the uranium deposits (economical definition, uranium ores, and deposits), the exploitation of uranium ores (use of radioactivity, radioprotection, effluents), the worldwide uranium resources (definition of the different categories and present day state of worldwide resources). (J.S.)
Philippines targeting unconventional sources for uranium
International Nuclear Information System (INIS)
Reyes, R.
2014-01-01
The quest for uranium in the Philippines dates back in the mid–1950s and to date about 70% of the country has been systematically explored, from reconnaissance to some detailed level using the combined radiometric and geochemical survey methods. However, no major uranium deposit has been discovered so far, only some minor mineralization. Also, there is a general view that the geological environment of the Philippines is unfavourable for uranium based on the lack of similarity between the geological features of known uranium–producing districts around the world and that of the country. It is in this light that the search for uranium in the country shifted to unconventional sources. The first unconventional source of uranium (U) that is being looked into is from rare earth elements (REE)–thorium (Th) minerals. Radiometric measurements along the beaches in northern Palawan identified major REE–Th and minor U potential areas. Heavy beach and stream panned concentrate gave high values of REE and Th, including U within the Ombo and Erawan coastal areas. Preliminary evaluation conducted in these two prospective areas indicated; 1) in the Ombo area, an estimated reserve of 750 t of Th, 30,450 t of REE and 80 t of U contained in about 540,000 t of beach sand with a respective average grade of 0.14% Th, 5.64% REE and 0.015% U, and 2) in the Erawan area, an estimated total reserve of 2,200 t of Th, 113,430 t of REE and 150 t U contained in 2,450,00 t of beach sand with an average grade of 0.09% Th, 4.63% REE and 0.006% U, respectively. Major allanite and minor monazite are the minerals identified and the source of these heavy minerals is the Tertiary Kapoas granitic intrusive rocks. Another unconventional source is a base metal zone with numerous occurrences containing complex assemblages of Cu–Mo–U within the Larap–Paracale mineralized district in Camarines Norte province, in which uranium may be produced as a by–product. A private mining company conducted
Study on thermoluminescence dating for Nideping terrace of Dongchuan, Yunnan province
International Nuclear Information System (INIS)
Zhang Bin; Wei Mingjian; Liu Chao; Zhang Yongdong; Zhou Rui; Liu Junxin; Liu Tiantian; Zhao Qiuyue; Song Bo
2013-01-01
The sequence of geological age on Nideping terrace in Dongchuan, Yunnan Province was established by thermoluminescence. The result shows that the age of the terrace is 9.3-57.1 ka. The vertical age of ancient debris flow terraces was established, and the time structure of Nideping mud was received. The age data was provided for the restoration ancient environment of the debris flow. It is shown that the debris flow deposits have discontinuities through age data and exist age inversion. The radioactive elements such as uranium, thorium, potassium may be leaching deposition affected by the presence of local rainfall and the annual dose rate increases with depth. (authors)
Pengaruh Kandungan Uranium Dalam Umpan Terhadap Efisiensi Pengendapan Uranium
Torowati
2010-01-01
PENGARUH KANDUNGAN URANIUM DALAM UMPAN TERHADAP EFISIENSI PENGENDAPAN URANIUM. Setiap aktivitas analisis di Laboratorium Kendali Kualitas, Bidang Bahan Bakar Nuklir selalu dihasilkan limbah radioaktif cair. Limbah radioaktif cair di laboratorium masih mengandung uranium yang cukup besar ± 0,600 g U/l dengan keasamaan yang cukup besar pula. Karena uranium mempunyai nilai ekonomis yang cukup tinggi maka perlu USAha untuk mengambil kembali uranium tersebut. Pada kegiatan ini telah dilak...
Glances on uranium. From uranium in the earth to electric power
International Nuclear Information System (INIS)
Valsardieu, C.
1995-01-01
This book is a technical, scientific and historical analysis of the nuclear fuel cycle from the origin of uranium in the earth and the exploitation of uranium ores to the ultimate storage of radioactive wastes. It comprises 6 chapters dealing with: 1) the different steps of uranium history (discovery, history of uranium chemistry, the radium era, the physicists and the structure of matter, the military uses, the nuclear power, the uranium industry and economics), 2) the uranium in nature (nuclear structure, physical-chemical properties, radioactivity, ores, resources, cycle, deposits), 3) the sidelights on uranium history (mining, prospecting, experience, ore processing, resources, reserves, costs), 4) the uranium in the fuel cycle, energy source and industrial product (fuel cycle, fission, refining, enrichment, fuel processing and reprocessing, nuclear reactors, wastes management), 5) the other energies in competition and the uranium market (other uranium uses, fossil fuels and renewable energies, uranium market), and 6) the future of uranium (forecasting, ecology, economics). (J.S.)
International Nuclear Information System (INIS)
Ali, Abdel Majid Abdel Galil Mohammed
1999-07-01
This investigation was carried out mainly to test the trace uranium level content in rock phosphate, which was used as a low cost fertilizer. Two types of rock phosphate were examined, namely, Kurun and Uro rocks from Nuba Mountains in the Southern Kurdufan province, Sudan.This area has a high background natural radioactivity. Moreover, it contains a rock phosphate zone lying between J. Kurun and Uro. The work included analytical methods carried out for thr rock phosphate samples using spectrophotometric and X-ray fluorescence techniques. The results obtained were compared with the data from literature and they showed a good agreement.The data was statistically analyzed to compare the results by the two techniques. The results of uranium content determined by the two analytical methods were significantly similar.The instrumental analysis revealed that different. Uranium content in the rocks phosphate samples of Uro type was found to be 1.6 times higher than Kurun type. (Author)
Uranium prospecting; La prospection de l'uranium
Energy Technology Data Exchange (ETDEWEB)
Roubault, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1955-07-01
This report is an instruction book for uranium prospecting. It appeals to private prospecting. As prospecting is now a scientific and technical research, it cannot be done without preliminary studies. First of all, general prospecting methods are given with a recall of fundamental geologic data and some general principles which are common with all type of prospecting. The peculiarities of uranium prospecting are also presented and in particular the radioactivity property of uranium as well as the special aspect of uranium ores and the aspect of neighbouring ores. In a third part, a description of the different uranium ores is given and separated in two different categories: primary and secondary ores, according to the place of transformation, deep or near the crust surface respectively. In the first category, the primary ores include pitchblende, thorianite and rare uranium oxides as euxenite and fergusonite for example. In the second category, the secondary ores contain autunite and chalcolite for example. An exhaustive presentation of the geiger-Mueller counter is given with the presentation of its different components, its functioning and utilization and its maintenance. The radioactivity interpretation method is showed as well as the elaboration of a topographic map of the measured radioactivity. A brief presentation of other detection methods than geiger-Mueller counters is given: the measurement of fluorescence and a chemical test using the fluorescence properties of uranium salts. Finally, the main characteristics of uranium deposits are discussed. (M.P.)
International Nuclear Information System (INIS)
Stewart, E.D.J.
1974-01-01
A discussion is given of uranium as an energy source in The Australian economy. Figures and predictions are presented on the world supply-demand position and also figures are given on the added value that can be achieved by the processing of uranium. Conclusions are drawn about Australia's future policy with regard to uranium (R.L.)
Uranium, depleted uranium, biological effects
International Nuclear Information System (INIS)
2001-01-01
Physicists, chemists and biologists at the CEA are developing scientific programs on the properties and uses of ionizing radiation. Since the CEA was created in 1945, a great deal of research has been carried out on the properties of natural, enriched and depleted uranium in cooperation with university laboratories and CNRS. There is a great deal of available data about uranium; thousands of analyses have been published in international reviews over more than 40 years. This presentation on uranium is a very brief summary of all these studies. (author)
Solubility measurement of uranium in uranium-contaminated soils
International Nuclear Information System (INIS)
Lee, S.Y.; Elless, M.; Hoffman, F.
1993-08-01
A short-term equilibration study involving two uranium-contaminated soils at the Fernald site was conducted as part of the In Situ Remediation Integrated Program. The goal of this study is to predict the behavior of uranium during on-site remediation of these soils. Geochemical modeling was performed on the aqueous species dissolved from these soils following the equilibration study to predict the on-site uranium leaching and transport processes. The soluble levels of total uranium, calcium, magnesium, and carbonate increased continually for the first four weeks. After the first four weeks, these components either reached a steady-state equilibrium or continued linearity throughout the study. Aluminum, potassium, and iron, reached a steady-state concentration within three days. Silica levels approximated the predicted solubility of quartz throughout the study. A much higher level of dissolved uranium was observed in the soil contaminated from spillage of uranium-laden solvents and process effluents than in the soil contaminated from settling of airborne uranium particles ejected from the nearby incinerator. The high levels observed for soluble calcium, magnesium, and bicarbonate are probably the result of magnesium and/or calcium carbonate minerals dissolving in these soils. Geochemical modeling confirms that the uranyl-carbonate complexes are the most stable and dominant in these solutions. The use of carbonate minerals on these soils for erosion control and road construction activities contributes to the leaching of uranium from contaminated soil particles. Dissolved carbonates promote uranium solubility, forming highly mobile anionic species. Mobile uranium species are contaminating the groundwater underlying these soils. The development of a site-specific remediation technology is urgently needed for the FEMP site
Uranium complex recycling method of purifying uranium liquors
International Nuclear Information System (INIS)
Elikan, L.; Lyon, W.L.; Sundar, P.S.
1976-01-01
Uranium is separated from contaminating cations in an aqueous liquor containing uranyl ions. The liquor is mixed with sufficient recycled uranium complex to raise the weight ratio of uranium to said cations preferably to at least about three. The liquor is then extracted with at least enough non-interfering, water-immiscible, organic solvent to theoretically extract about all of the uranium in the liquor. The organic solvent contains a reagent which reacts with the uranyl ions to form a complex soluble in the solvent. If the aqueous liquor is acidic, the organic solvent is then scrubbed with water. The organic solvent is stripped with a solution containing at least enough ammonium carbonate to precipitate the uranium complex. A portion of the uranium complex is recycled and the remainder can be collected and calcined to produce U 3 O 8 or UO 2
International Nuclear Information System (INIS)
Toens, P.D.
1981-03-01
The geological setting of uranium resources in the world can be divided in two basic categories of resources and are defined as reasonably assured resources, estimated additional resources and speculative resources. Tables are given to illustrate these definitions. The increasing world production of uranium despite the cutback in the nuclear industry and the uranium requirements of the future concluded these lecture notes
International Nuclear Information System (INIS)
Bolivar, S.L.; Broxton, D.E.; Olsen, C.E.
1978-03-01
Although this report covers two National Topographic Map Series 2 0 quadrangles, the data for each quadrangle are presented separately. Evaluation of the data by quadrangle resulted in the delineation of areas in which water and/or sediment uranium concentrations are notably higher than surrounding background concentrations. The major clusters of anomalous water samples were found in areas of the Denver Basin underlain by the Pierre, Laramie, Fox Hills, Denver, and Arapahoe formations. Most of the anomalous sediment samples were collected in areas of the Front Range underlain by Precambrian crystalline rocks, particularly granites of the Silver Plume-Sherman group. Many of the anomalous sediment samples are from sites located near fault zones. The data in this report are also presented by geologic/physiographic province because background uranium concentrations in Front Range samples differ significantly from those in the Denver Basin. Denver Basin waters have higher mean uranium concentrations (mean 14.4 ppB) than Front Range waters (mean 3.3 ppB). Conversely, Front Range sediments are more uraniferous (mean 14.7 ppM) than those in the Denver Basin (mean 6.1 ppM). These differences in background uranium concentrations between Front Range and Denver Basin samples can be attributed to differences in regional geology, physiography, and (in the case of water) the ratio of surface water to ground water sites sampled. There is a significant northward increase in uranium concentrations in water samples from the Denver Basin. The higher uranium concentrations in water samples from the northern part of the basin are probably due to leaching of uraniferous strata in the Pierre and Laramie formations which crop out in that area
Recovery of uranium from uranium bearing black shale
International Nuclear Information System (INIS)
Das, Amrita; Yadav, Manoj; Singh, Ajay K.
2016-01-01
Black shale is the unconventional resource of uranium. Recovery of uranium from black shale has been carried out by the following steps: i) size reduction, ii) leaching of uranium in the aqueous medium, iii) fluoride ion removal, iv) solvent extraction of uranium from the aqueous leach solution, v) scrubbing of the loaded solvent after extraction to remove impurities as much as possible and vi) stripping of uranium from the loaded organic into the aqueous phase. Leaching of black shale has been carried out in hydrochloric acid. Free acidity of the leach solution has been determined by potentiometric titration method. Removal of fluoride ions has been done using sodium chloride. Solvent extraction has been carried out by both tributyl phosphate and alamine-336 as extractants. Scrubbing has been tried with oxalic acid and sulphuric acid. Stripping with sodium carbonate solution has been carried out. Overall recovery of uranium is 95%. (author)
International Nuclear Information System (INIS)
1983-01-01
The specific character of uranium as energy resources, the history of development of uranium resources, the production and reserve of uranium in the world, the prospect regarding the demand and supply of uranium, Japanese activity of exploring uranium resources in foreign countries and the state of development of uranium resources in various countries are reported. The formation of uranium deposits, the classification of uranium deposits and the reserve quantity of each type are described. As the geological environment of uranium deposits, there are six types, that is, quartz medium gravel conglomerate deposit, the deposit related to the unconformity in Proterozoic era, the dissemination type magma deposit, pegmatite deposit and contact deposit in igneaus rocks and metamorphic rocks, vein deposit, sandstone type deposit and the other types of deposit. The main features of respective types are explained. The most important uranium resources in Japan are those in the Tertiary formations, and most of the found reserve belongs to this type. The geological features, the state of yield and the scale of the deposits in Ningyotoge, Tono and Kanmon Mesozoic formation are reported. Uranium minerals, the promising districts in the world, and the matters related to the exploration and mining of uranium are described. (Kako, I.)
International Nuclear Information System (INIS)
Jackson, D.; Marshall, E.; Sideris, T.; Vasa-Sideris, S.
2001-01-01
One of the missions of the Department of Energy's (DOE) Oak Ridge Office (ORO) has been the management of the Department's uranium materials. This mission has been accomplished through successful integration of ORO's uranium activities with the rest of the DOE complex. Beginning in the 1980's, several of the facilities in that complex have been shut down and are in the decommissioning process. With the end of the Cold War, the shutdown of many other facilities is planned. As a result, inventories of uranium need to be removed from the Department facilities. These inventories include highly enriched uranium (HEU), low enriched uranium (LEU), normal uranium (NU), and depleted uranium (DU). The uranium materials exist in different chemical forms, including metals, oxides, solutions, and gases. Much of the uranium in these inventories is not needed to support national priorities and programs. (author)
Uptake of uranium by native aquatic plants: potential for bioindication and phytoremediation
Directory of Open Access Journals (Sweden)
Favas P. J. C.
2013-04-01
Full Text Available The work presented here is a part the on going study on the uraniferous geochemical province of Central Portugal in which, the use of aquatic plants as indicators of uranium contamination is being probed using aquatic plants emphasizing their potential use in the emerging phytotechnologies. Even though we have observed very low concentration of U in the fresh waters of the studied sites we found a set of vegetable species with the ability to accumulate U in concentrations which are orders of magnitude higher than the surrounding environment. We have observed that Apium nodiflorum, Callitriche stagnalis, Lemna minor and Fontinalis antipyretica accumulated significant amounts of uranium, whereas Oenanthe crocata excluded U. These results indicate substantial scope for proper radiophytoremediation and phytosociological investigation exploiting the native flora. These species show great potential for phytoremediation because they are endemic and easy to grow in their native conditions. A. nodiflorum and C. stagnalis have high bioproductivity and yield good biomass.
Simulated real-time process monitoring of a molten salt electrorefiner
International Nuclear Information System (INIS)
Rappleye, Devin; Simpson, Michael; Cumberland, Riley; McNelis, David; Yim, Man-Sung
2014-01-01
Highlights: • An alternative approach to safeguarding and monitoring pyroprocessing is proposed. • Possible signals to be used to monitor an electrorefiner are identified. • An inverse model was developed to determine deposition rates at the cathode. • The sensitivity of certain parameters in the inverse model are presented. - Abstract: An alternative approach to monitoring the pyrochemical process (pyroprocessing) for spent nuclear fuel treatment is proposed and examined. This approach relies on modeling and the real-time analysis of process readings. Using an electrorefiner model, named ERAD, cathode potential and cell current were identified as useful process readings. To provide a real-time analysis of these two process readings, an inverse model was developed based on fundamental electrochemical relations. The model was applied to the following operating modes: pure uranium deposition, co-deposition of uranium and plutonium, and co-deposition of uranium and zirconium. Using the cell current and cathode potential, the model predicted which species were depositing and their rates. The deposition rates predicted by the inverse model compared favorably to those calculated by ERAD
Energy Technology Data Exchange (ETDEWEB)
Kuo, Li-Jung [Marine; Pan, Horng-Bin [Department; Wai, Chien M. [Department; Byers, Margaret F. [Nuclear; Schneider, Erich [Nuclear; Strivens, Jonathan E. [Marine; Janke, Christopher J. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831, United States; Das, Sadananda [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831, United States; Mayes, Richard T. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831, United States; Wood, Jordana R. [Marine; Schlafer, Nicholas [Marine; Gill, Gary A. [Marine
2017-09-29
The ability to re-use amidoxime-based polymeric adsorbents is a critical component in reducing the overall cost of the technology to extract uranium from seawater. This report describes an evaluation of adsorbent reusability in multiple re-use (adsorption/stripping) cycles in real seawater exposures with potassium bicarbonate (KHCO3) elution using several amidoxime-based polymeric adsorbents. The KHCO3 elution technique achieved ~100% recovery of uranium adsorption capacity in the first re-use. Subsequent re-uses showed significant drops in adsorption capacity. After the 4th re-use with the ORNL AI8 adsorbent, the 56-day adsorption capacity dropped to 28% of its original capacity. FTIR spectra revealed that there was a conversion of the amidoxime ligands to carboxylate groups during extended seawater exposure, becoming more significant with longer the exposure time. Ca and Mg adsorption capacities also increased with each re-use cycle supporting the hypothesis that long term exposure resulted in converting amidoxime to carboxylate, enhancing the adsorption of Ca and Mg. Shorter seawater exposure (adsorption/stripping) cycles (28 vs. 42 days) had higher adsorption capacities after re-use, but the shorter exposure cycle time did not produce an overall better performance in terms of cumulative exposure time. Recovery of uranium capacity in re-uses may also vary across different adsorbent formulations. Through multiple re-use the adsorbent AI8 can harvest 10 g uranium/kg adsorbent in ~140 days, using a 28-day adsorption/stripping cycle, a performance much better than would be achieved with a single use of the adsorbent through very long-term exposure (saturation capacity = 7.4 g U/kg adsorbent). A time dependent seawater exposure model to evaluate the cost associated with reusing amidoxime-based adsorbents in real seawater exposures was developed. The cost to extract uranium from seawater ranged from $610-830/kg U was predicted. Model simulation suggests that a short
Provision by the uranium and uranium products
International Nuclear Information System (INIS)
Elagin, Yu.P.
2005-01-01
International uranium market is converted from the buyer market into the seller market. The prices of uranium are high and the market attempts to adapt to changing circumstances. The industry of uranium enrichment satisfies the increasing demands but should to increase ots capacities. On the whole the situation is not stable and every year may change the existing position [ru
International Nuclear Information System (INIS)
Riley, K.
2008-01-01
The global uranium market is undergoing a major expansion due to an increase in global demand for uranium, the highest uranium prices in the last 20 years and recognition of the potential greenhouse benefits of nuclear power. Australia holds approximately 27% of the world's uranium resources (recoverable at under US$80/kg U), so is well placed to benefit from the expansion in the global uranium market. Increasing exploration activity due to these factors is resulting in the discovery and delineation of further high grade uranium deposits and extending Australia's strategic position as a reliable and safe supplier of low cost uranium.
High-temperature thermal conductivity of uranium chromite and uranium niobate
International Nuclear Information System (INIS)
Fedoseev, D.V.; Varshavskaya, I.G.; Lavrent'ev, A.V.; Oziraner, S.N.; Kuznetsova, D.G.
1979-01-01
The technique of determining thermal conductivity coefficient of uranium niobate and uranium chromite on heating with laser radiation is described. Determined is the coefficient of free-convective heat transfer (with provision for a conduction component) by means of a standard specimen. The thermal conductivity coefficients of uranium chromite and niobate were measured in the 1300-1700 K temperature range. The results are presented in a diagram form. It has been calculated, that the thermal conductivity coefficient for uranium niobate specimens is greater in comparison with uranium chromite specimens. The thermal conductivity coefficients of the materials mentioned depend on temperature very slightly. Thermal conductivity of the materials considerably depends on their porosity. The specimens under investigation were fabricated by the pressing method and had the following porosity: uranium chromite - 30 %, uranium niobate - 10 %. Calculation results show, that thermal conductivity of dense uranium chromite is higher than thermal conductivity of dense uranium niobate. The experimental error equals approximately 20 %, that is mainly due to the error of measuring the temperature equal to +-25 deg, with a micropyrometer
Energy Technology Data Exchange (ETDEWEB)
Lecraz, C
1993-06-11
A new type of combustible elements which is a mixture of uranium nitride and uranium-plutonium oxide could be used for Quick Neutrons Reactors. Three different studies have been made on the one hand on the reactions between uranium nitride (UN) and uranium-plutonium mixed oxide (U,Pu)O{sub 2}, on the other hand on these between UN and uranium oxide UO{sub 2}. They show a sizeable reaction between nitride and oxide for the studied temperatures range (1573 K to 1973 K). This reaction forms a oxynitride compound, MO{sub x} N{sub y} with M=U or M=(U,Pu), whose crystalline structure is similar to oxide`s. Solubility of nitride in both oxides is studied, as the reaction kinetics. (TEC). 32 refs., 48 figs., 22 tabs.
International Nuclear Information System (INIS)
Li Guangyue; Liu Yulong; Wang Yongdong; Ding Dexin
2009-01-01
The sulphuric acid leaching and bacteria leaching by orbital shaker experiments were conducted for the low grade uranium ore from a uranium mine in Guangdong Province. The results show that, when the concentration of sulphuric acid and that of slurry were 30 g/L and 25%, respectively, the conditions were most favourable for sulphuric acid leaching and the rate of leaching reached 92.92%, that, when pH value was 1.5, inoculation amount, 10%, concentration of slurry, 10%, the conditions were most favourable for bacteria leaching and the rate of leaching reached 95.93%, that, compared with sulphuric acid leaching, bacteria leaching decreased sulphuric acid consumption by 17.2% and increased the rate of leaching by 3%, and that, under the most favourable conditions for suphuric acid leaching, if 1% natrium chlorate was added, the rate of leaching increased to 96.46%, but 10 kg of natrium chlorate was consumed for 1 ton of uranium ore. (authors)
International Nuclear Information System (INIS)
1997-04-01
The Uranium Industry Annual 1996 (UIA 1996) provides current statistical data on the US uranium industry's activities relating to uranium raw materials and uranium marketing. The UIA 1996 is prepared for use by the Congress, Federal and State agencies, the uranium and nuclear electric utility industries, and the public. Data on uranium raw materials activities for 1987 through 1996 including exploration activities and expenditures, EIA-estimated reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities for 1994 through 2006, including purchases of uranium and enrichment services, enrichment feed deliveries, uranium fuel assemblies, filled and unfilled market requirements, uranium imports and exports, and uranium inventories are shown in Chapter 2. A feature article, The Role of Thorium in Nuclear Energy, is included. 24 figs., 56 tabs
Energy Technology Data Exchange (ETDEWEB)
NONE
1997-04-01
The Uranium Industry Annual 1996 (UIA 1996) provides current statistical data on the US uranium industry`s activities relating to uranium raw materials and uranium marketing. The UIA 1996 is prepared for use by the Congress, Federal and State agencies, the uranium and nuclear electric utility industries, and the public. Data on uranium raw materials activities for 1987 through 1996 including exploration activities and expenditures, EIA-estimated reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities for 1994 through 2006, including purchases of uranium and enrichment services, enrichment feed deliveries, uranium fuel assemblies, filled and unfilled market requirements, uranium imports and exports, and uranium inventories are shown in Chapter 2. A feature article, The Role of Thorium in Nuclear Energy, is included. 24 figs., 56 tabs.
Production of sized particles of uranium oxides and uranium oxyfluorides
International Nuclear Information System (INIS)
Knudsen, I.E.; Randall, C.C.
1976-01-01
A process is claimed for converting uranium hexafluoride (UF 6 ) to uranium dioxide (UO 2 ) of a relatively large particle size in a fluidized bed reactor by mixing uranium hexafluoride with a mixture of steam and hydrogen and by preliminary reacting in an ejector gaseous uranium hexafluoride with steam and hydrogen to form a mixture of uranium and oxide and uranium oxyfluoride seed particles of varying sizes, separating the larger particles from the smaller particles in a cyclone separator, recycling the smaller seed particles through the ejector to increase their size, and introducing the larger seed particles from the cyclone separator into a fluidized bed reactor where the seed particles serve as nuclei on which coarser particles of uranium dioxide are formed. 9 claims, 2 drawing figures
Uranium 2000 : International symposium on the process metallurgy of uranium
International Nuclear Information System (INIS)
Ozberk, E.; Oliver, A.J.
2000-01-01
The International Symposium on the Process Metallurgy of Uranium has been organized as the thirtieth annual meeting of the Hydrometallurgy Section of the Metallurgical Society of the Canadian Institute of Mining, Metallurgy and Petroleum (CIM). This meeting is jointly organized with the Canadian Mineral Processors Division of CIM. The proceedings are a collection of papers from fifteen countries covering the latest research, development, industrial practices and regulatory issues in uranium processing, providing a concise description of the state of this industry. Topics include: uranium industry overview; current milling operations; in-situ uranium mines and processing plants; uranium recovery and further processing; uranium leaching; uranium operations effluent water treatment; tailings disposal, water treatment and decommissioning; mine decommissioning; and international regulations and decommissioning. (author)
International Nuclear Information System (INIS)
Cole, D.I.
1980-01-01
The sedimentology of some uranium-bearing sandstones from the Beaufort Group in the Beaufort West area was studied by use of some 116 vertical profiles measured across and adjacent to 14 mineralized deposits. The vertical profiles consist of 91 field sections and 25 borehole logs. The sandstones are usually multistorey and alternate with a mudstone and/or siltstone succession. The vertical profiles basically consist of a succession of facies. Some 19 facies were recognised within the sandstones on the basis of texture and sedimentary structure. The facies transitions within the sandstone sequence were subjected to a one-step Markov chain analysis. The cumulative thickness of uranium mineralization for each sedimentary facies within the sandstone sequence was measured. Some 99 per cent of the total cumulative thickness occurs within the coarser-grained facies (grain sizes in excess of very fine), which suggests that permeability was an important control on the mineralization. The coarser-grained facies, which mostly represent lower point bar or channel bar deposits near the base of each storey, probably acted as suitable aquifers for the transport of uraniferous solutions. Irregularities in the base of each storey may have interrupted the flow of these solutions and allowed sufficient time for precipitation of the uranium. Carbonaceous debris is frequently associated with the mineralized deposits and most likely acted as an indirect reductant for this precipitation. Mineralization decreases upwards in the sandstone sequence and some 40 per cent of the total cumulative thickness is restricted to the initial storey. The horizontally bedded facies contain a high proportion of the total cumulative thickness of mineralization (45 per cent) and this again may be related to a more abundant content of carbonaceous debris
International Nuclear Information System (INIS)
1993-01-01
The Uranium Industry Annual provides current statistical data on the US uranium industry for the Congress, Federal and State agencies, the uranium and electric utility industries, and the public. The feature article, ''Decommissioning of US Conventional Uranium Production Centers,'' is included. Data on uranium raw materials activities including exploration activities and expenditures, resources and reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities including domestic uranium purchases, commitments by utilities, procurement arrangements, uranium imports under purchase contracts and exports, deliveries to enrichment suppliers, inventories, secondary market activities, utility market requirements, and uranium for sale by domestic suppliers are presented in Chapter 2
Energy Technology Data Exchange (ETDEWEB)
1993-10-28
The Uranium Industry Annual provides current statistical data on the US uranium industry for the Congress, Federal and State agencies, the uranium and electric utility industries, and the public. The feature article, ``Decommissioning of US Conventional Uranium Production Centers,`` is included. Data on uranium raw materials activities including exploration activities and expenditures, resources and reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities including domestic uranium purchases, commitments by utilities, procurement arrangements, uranium imports under purchase contracts and exports, deliveries to enrichment suppliers, inventories, secondary market activities, utility market requirements, and uranium for sale by domestic suppliers are presented in Chapter 2.
International Nuclear Information System (INIS)
Huffer, E.; Nifenecker, H.
2001-02-01
This document deals with the physical, chemical and radiological properties of the depleted uranium. What is the depleted uranium? Why do the military use depleted uranium and what are the risk for the health? (A.L.B.)
Pyrophoric behaviour of uranium hydride and uranium powders
Le Guyadec, F.; Génin, X.; Bayle, J. P.; Dugne, O.; Duhart-Barone, A.; Ablitzer, C.
2010-01-01
Thermal stability and spontaneous ignition conditions of uranium hydride and uranium metal fine powders have been studied and observed in an original and dedicated experimental device placed inside a glove box under flowing pure argon. Pure uranium hydride powder with low amount of oxide (Oxidation mechanisms are proposed.
RECOVERY OF URANIUM FROM ZIRCONIUM-URANIUM NUCLEAR FUELS
Gens, T.A.
1962-07-10
An improvement was made in a process of recovering uranium from a uranium-zirconium composition which was hydrochlorinated with gsseous hydrogen chloride at a temperature of from 350 to 800 deg C resulting in volatilization of the zirconium, as zirconium tetrachloride, and the formation of a uranium containing nitric acid insoluble residue. The improvement consists of reacting the nitric acid insoluble hydrochlorination residue with gaseous carbon tetrachloride at a temperature in the range 550 to 600 deg C, and thereafter recovering the resulting uranium chloride vapors. (AEC)
Uranium prospecting; La prospection de l'uranium
Energy Technology Data Exchange (ETDEWEB)
Roubault, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1955-07-01
This report is an instruction book for uranium prospecting. It appeals to private prospecting. As prospecting is now a scientific and technical research, it cannot be done without preliminary studies. First of all, general prospecting methods are given with a recall of fundamental geologic data and some general principles which are common with all type of prospecting. The peculiarities of uranium prospecting are also presented and in particular the radioactivity property of uranium as well as the special aspect of uranium ores and the aspect of neighbouring ores. In a third part, a description of the different uranium ores is given and separated in two different categories: primary and secondary ores, according to the place of transformation, deep or near the crust surface respectively. In the first category, the primary ores include pitchblende, thorianite and rare uranium oxides as euxenite and fergusonite for example. In the second category, the secondary ores contain autunite and chalcolite for example. An exhaustive presentation of the geiger-Mueller counter is given with the presentation of its different components, its functioning and utilization and its maintenance. The radioactivity interpretation method is showed as well as the elaboration of a topographic map of the measured radioactivity. A brief presentation of other detection methods than geiger-Mueller counters is given: the measurement of fluorescence and a chemical test using the fluorescence properties of uranium salts. Finally, the main characteristics of uranium deposits are discussed. (M.P.)
International Nuclear Information System (INIS)
1980-01-01
This report contains the papers delivered at the Summer School on Uranium Health Physics held in Pretoria on the 14 and 15 April 1980. The following topics were discussed: uranium producton in South Africa; radiation physics; internal dosimetry and radiotoxicity of long-lived uranium isotopes; uranium monitoring; operational experience on uranium monitoring; dosimetry and radiotoxicity of inhaled radon daughters; occupational limits for inhalation of radon-222, radon-220 and their short-lived daughters; radon monitoring techniques; radon daughter dosimeters; operational experience on radon monitoring; and uranium mill tailings management
Energy Technology Data Exchange (ETDEWEB)
Spriggs, M J
1976-01-01
Papers were presented on the pattern of uranium production in South Africa; Australian uranium--will it ever become available; North American uranium resources, policies, prospects, and pricing; economic and political environment of the uranium mining industry; alternative sources of uranium supply; whither North American demand for uranium; and uranium demand and security of supply--a consumer's point of view. (LK)
International Nuclear Information System (INIS)
1992-10-01
In the Uranium Industry Annual 1991, data on uranium raw materials activities including exploration activities and expenditures, resources and reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities including domestic uranium purchases, commitments by utilities, procurement arrangements, uranium imports under purchase contracts and exports, deliveries to enrichment suppliers, inventories, secondary market activities, utility market requirements, and uranium for sale by domestic suppliers are presented in Chapter 2. A feature article entitled ''The Uranium Industry of the Commonwealth of Independent States'' is included in this report
Uranium price reporting systems
International Nuclear Information System (INIS)
1987-09-01
This report describes the systems for uranium price reporting currently available to the uranium industry. The report restricts itself to prices for U 3 O 8 natural uranium concentrates. Most purchases of natural uranium by utilities, and sales by producers, are conducted in this form. The bulk of uranium in electricity generation is enriched before use, and is converted to uranium hexafluoride, UF 6 , prior to enrichment. Some uranium is traded as UF 6 or as enriched uranium, particularly in the 'secondary' market. Prices for UF 6 and enriched uranium are not considered directly in this report. However, where transactions in UF 6 influence the reported price of U 3 O 8 this influence is taken into account. Unless otherwise indicated, the terms uranium and natural uranium used here refer exclusively to U 3 O 8 . (author)
Environmental planning in uranium milling
International Nuclear Information System (INIS)
Bertello, L.F.
1987-01-01
Effluents from uranium milling in the Achala region in the province of Cordoba are studied. Liquids from lixiviation-recovery and from precipitation-washing of yellow-cake were analyzed. Separation of both liquids before treatment and disposal is recommended. Data of the hydric environment are presented specially for volumes of flow. The disposal criteria established by the provincial authorities are presented, and discussed. Calculations to define the effects on the environment of two types of effluents (the leaching effluent without treatment and the same after treating it) on two points of the rivers net, are given and the results discussed. A disposal policy for a treated effluent of mean composition is presented, based on two different amounts for the two phases of the river flux; the possible effects on two points of the net were also calculated. In the author's opinion, such policy will result in a disposal without a sensible damage in the receptor. (Author) [es
Formation mechanism of uranium minerals at sandstone-type uranium deposits
International Nuclear Information System (INIS)
Li Shengfu; Zhang Yun
2004-01-01
By analyzing the behavior and existence form of uranium in different geochemical environments, existence form of uranium and uranium minerals species, this paper expounds the formation mechanism of main commercial uranium mineral--pitchblende: (1) uranium is a valence-changeable element. It is reactivated and migrates in oxidized environment, and is reduced and precipitated in reducing environment; (2) [UO 2 (CO 3 ) 3 ] 4- , [UO 2 (CO 3 ) 2 ] 2- coming from oxidized environment react with reductants such as organic matter, sulfide and low-valence iron at the redox front to form simple uranium oxide--pitchblende; (3)the adsorption of uranium by organic matter and clay minerals accelerates the reduction and the concentration of uranium. Therefore, it is considered, that the reduction of SO 4 2- by organic matter to form H 2 S, and the reduction of UO 2 2+ by H 2 S are the main reasons for the formation of pitchblende. This reaction is extensively and universally available in neutral and weakly alkaline carbonate solution. The existense of reductants such as H 2 S is the basic factor leading to the decrease of Eh in environments and the oversaturation of UO 2 2+ at the redox front in groundwater, thus accelerating the adsorption and the precipitation of uranium
International Nuclear Information System (INIS)
1990-01-01
This report looks at the following issues: How much Soviet uranium ore and enriched uranium are imported into the United States and what is the extent to which utilities flag swap to disguise these purchases? What are the U.S.S.R.'s enriched uranium trading practices? To what extent are utilities required to return used fuel to the Soviet Union as part of the enriched uranium sales agreement? Why have U.S. utilities ended their contracts to buy enrichment services from DOE?
Energy Technology Data Exchange (ETDEWEB)
Warner, R K
1976-04-01
Various aspects of the Australian uranium industry are discussed including the prospecting, exploration and mining of uranium ores, world supply and demand, the price of uranium and the nuclear fuel cycle. The market for uranium and the future development of the industry are described.
International Nuclear Information System (INIS)
Thomas, D.C.; Gagne, R.W.
1978-01-01
The following topics are covered: the status of the Government's existing uranium enrichment services contracts, natural uranium requirements based on the latest contract information, uncertainty in predicting natural uranium requirements based on uranium enrichment contracts, and domestic and foreign demand assumed in enrichment planning
International Nuclear Information System (INIS)
Mehdizadeh, S.; Faghihi, R.; Sina, S.; Derakhshan, S.
2013-01-01
The Fars province is located in the south-west region of Iran where different nuclear sites has been established, such as Bushehr Nuclear Power Plant. In this research, 92 water samples from the water supplies of Shiraz city and springs of the Fars province were investigated with regard to the concentrations of natural radioactive elements, total uranium, 226 Ra, gross alpha and gross beta. 226 Ra concentration was determined by the 222 Rn emanation method. To measure the total uranium concentration, a laser fluorimetry analyzer (UA-3) was used. The mean concentration of 226 Ra in Shiraz's water resources was 23.9 mBq l -1 , while 93% of spring waters have a concentration 2 mBq l -1 . The results of uranium concentration measurements show the mean concentrations of 7.6 and 6 mg l -1 in the water of Shiraz and springs of Fars, respectively. The gross alpha and beta concentrations measured by the evaporation method were lower than the limit of detection of the measuring instruments used in this survey. The mean annual effective doses of infants, children and adults from 238 U and 226 Ra content of Shiraz's water and spring waters were estimated. According to the results of this study, the activity concentration in water samples were below the maximum permissible concentrations determined by the World Health Organization and the US Environmental Protection Agency. Finally, the correlation between 226 Ra and total U activity concentrations and geochemical properties of water samples, i.e. pH, total dissolve solids and SO 4 2- , were estimated. (authors)
Uranium isotope evidence for an expansion of marine anoxia during the end-Triassic extinction
Jost, Adam B.; Bachan, Aviv; van de Schootbrugge, Bas; Lau, Kimberly V.; Weaver, Karrie L.; Maher, Kate; Payne, Jonathan L.
2017-08-01
The end-Triassic extinction coincided with an increase in marine black shale deposition and biomarkers for photic zone euxinia, suggesting that anoxia played a role in suppressing marine biodiversity. However, global changes in ocean anoxia are difficult to quantify using proxies for local anoxia. Uranium isotopes (δ238U) in CaCO3 sediments deposited under locally well-oxygenated bottom waters can passively track seawater δ238U, which is sensitive to the global areal extent of seafloor anoxia due to preferential reduction of 238U(VI) relative to 235U(VI) in anoxic marine sediments. We measured δ238U in shallow-marine limestones from two stratigraphic sections in the Lombardy Basin, northern Italy, spanning over 400 m. We observe a ˜0.7‰ negative excursion in δ238U beginning in the lowermost Jurassic, coeval with the onset of the initial negative δ13C excursion and persisting for the duration of subsequent high δ13C values in the lower-middle Hettangian stage. The δ238U excursion cannot be realistically explained by local mixing of uranium in primary marine carbonate and reduced authigenic uranium. Based on output from a forward model of the uranium cycle, the excursion is consistent with a 40-100-fold increase in the extent of anoxic deposition occurring worldwide. Additionally, relatively constant uranium concentrations point toward increased uranium delivery to the oceans from continental weathering, which is consistent with weathering-induced eutrophication following the rapid increase in pCO2 during emplacement of the Central Atlantic Magmatic Province. The relative timing and duration of the excursion in δ238U implies that anoxia could have delayed biotic recovery well into the Hettangian stage.
International Nuclear Information System (INIS)
Gagne, R.W.; Thomas, D.C.
1977-01-01
The status of existing uranium enrichment contracts in the US is reviewed and expected natural uranium requirements for existing domestic uranium enrichment contracts are evaluated. Uncertainty in natural uranium requirements associated with requirements-type and fixed-commitment type contracts is discussed along with implementation of variable tails assay
International Nuclear Information System (INIS)
Guenther, A.; Bernhard, G.; Geipel, G.; Reich, T.; Rossberg, A.; Nitsche, H.
2003-01-01
Detailed knowledge of the nature of uranium complexes formed after the uptake by plants is an essential prerequisite to describe the migration behavior of uranium in the environment. This study focuses on the determination of uranium speciation after uptake of uranium by lupine plants. For the first time, time-resolved laser-induced fluorescence spectroscopy and X-ray absorption spectroscopy were used to determine the chemical speciation of uranium in plants. Differences were detected between the uranium speciation in the initial solution (hydroponic solution and pore water of soil) and inside the lupine plants. The oxidation state of uranium did not change and remained hexavalent after it was taken up by the lupine plants. The chemical speciation of uranium was identical in the roots, shoot axis, and leaves and was independent of the uranium speciation in the uptake solution. The results indicate that the uranium is predominantly bound as uranyl(VI) phosphate to the phosphoryl groups. Dandelions and lamb's lettuce showed uranium speciation identical to lupine plants. (orig.)
Uranium recovering from slags generated in the metallic uranium by magnesiothermic reduction
International Nuclear Information System (INIS)
Fornarolo, F.; Carvalho, E.F. Urano de; Durazzo, M.; Riella, H.G.
2008-01-01
The Nuclear Fuel Center of IPEN/CNEN-SP has recent/y concluded a program for developing the fabrication technology of the nuclear fuel based on the U 3 Si 2 -Al dispersion, which is being used in the IEA-R1 research reactor. The uranium silicide (U 3 Si 2 ) fuel production starts with the uranium hexafluoride (UF 6 ) processing and uranium tetrafluoride (UF 4 ) precipitation. Then, the UF 4 is converted to metallic uranium by magnesiothermic reduction. The UF 4 reduction by magnesium generates MgF 2 slag containing considerable concentrations of uranium, which could reach 20 wt%. The uranium contained in that slag should be recovered and this work presents the results obtained in recovering the uranium from that slag. The uranium recovery is accomplished by acidic leaching of the calcined slag. The calcination transforms the metallic uranium in U 3 O 8 , promoting the pulverization of the pieces of metallic uranium and facilitating the leaching operation. As process variables, have been considered the nitric molar concentration, the acid excess regarding the stoichiometry and the leaching temperature. As result, the uranium recovery reached a 96% yield. (author)
Process for producing uranium oxide rich compositions from uranium hexafluoride
International Nuclear Information System (INIS)
DeHollander, W.R.; Fenimore, C.P.
1978-01-01
Conversion of gaseous uranium hexafluoride to a uranium dioxide rich composition in the presence of an active flame in a reactor defining a reaction zone is achieved by separately introducing a first gaseous reactant comprising a mixture of uranium hexafluoride and a reducing carrier gas, and a second gaseous reactant comprising an oxygen-containing gas. The reactants are separated by a shielding gas as they are introduced to the reaction zone. The shielding gas temporarily separates the gaseous reactants and temporarily prevents substantial mixing and reacting of the gaseous reactants. The flame occurring in the reaction zone is maintained away from contact with the inlet introducing the mixture to the reaction zone. After suitable treatment, the uranium dioxide rich composition is capable of being fabricated into bodies of desired configuration for loading into nuclear fuel rods. Alternatively, an oxygen-containing gas as a third gaseous reactant is introduced when the uranium hexafluoride conversion to the uranium dioxide rich composition is substantially complete. This results in oxidizing the uranium dioxide rich composition to a higher oxide of uranium with conversion of any residual reducing gas to its oxidized form
Formation conditions of uranium minerals in oxidation zone of uranium deposits
International Nuclear Information System (INIS)
Li Youzhu
2005-01-01
The paper concerns about the summary and classification of hydrothermal uranium deposit with oxidation zone. Based on the summary of observation results of forty uranium deposits located in CIS and Bulgaria which are of different sizes and industrial-genetic types, analysis on available published information concerning oxidation and uranium mineral enrichment in supergenic zone, oxidation zone classification of hydrothermal uranium had been put forward according to the general system of the exogenetic uranium concentration. (authors)
International Nuclear Information System (INIS)
1995-01-01
The Uranium Industry Annual 1994 (UIA 1994) provides current statistical data on the US uranium industry's activities relating to uranium raw materials and uranium marketing during that survey year. The UIA 1994 is prepared for use by the Congress, Federal and State agencies, the uranium and nuclear electric utility industries, and the public. It contains data for the 10-year period 1985 through 1994 as collected on the Form EIA-858, ''Uranium Industry Annual Survey.'' Data collected on the ''Uranium Industry Annual Survey'' (UIAS) provide a comprehensive statistical characterization of the industry's activities for the survey year and also include some information about industry's plans and commitments for the near-term future. Where aggregate data are presented in the UIA 1994, care has been taken to protect the confidentiality of company-specific information while still conveying accurate and complete statistical data. A feature article, ''Comparison of Uranium Mill Tailings Reclamation in the United States and Canada,'' is included in the UIA 1994. Data on uranium raw materials activities including exploration activities and expenditures, EIA-estimated resources and reserves, mine production of uranium, production of uranium concentrate, and industry employment are presented in Chapter 1. Data on uranium marketing activities, including purchases of uranium and enrichment services, and uranium inventories, enrichment feed deliveries (actual and projected), and unfilled market requirements are shown in Chapter 2
Geological-geochemical evidence for deep fluid action in Daqiaowu uranium deposit, Zhejiang province
International Nuclear Information System (INIS)
Qiu Linfei; Ou Guangxi; Zhang Jianfeng; Zhang Min; Jin Miaozhang; Wang Binghua
2009-01-01
Through the contrast study of petrography, micro thermometry and laser Raman ingredient analysis of fluid inclusion, this paper has verified the basic nature of ore-forming fluid (temperature, salinity and ingredient) in daqiaowu uranium deposit, discussed the origin of the ore-forming fluid with its structure character and geology-geochemistry character. The testing results indicats that ore-forming temperature of this deposit is between 200 degree C and 250 degree C in main metallogenetic period, which belongs to middle temperature hydrothermal. The ore-forming fluids are of middle-high salinity and rich in valatility suchas CO 2 , H 2 , CH 4 . To sum up, the deposit mineralization process should be affected by the deep fluid primarily, and the ore-forming fluid is mainly the mantle fluid.(authors)
International Nuclear Information System (INIS)
1977-11-01
The report deals almost exclusively with Greenland. A major omission is any broad description of the geology of the island. One which can be recommended is 'A survey of the economic geology of Greenland' by B.J. Nielsen published by the Geological Survey of Greenland. Nielsen has also published several articles on the uranium occurrences in Greenland, some of which are noted in the references. A review of the geology is necessary in order to determine how the known occurrences fit into the pattern of uranium mineralisation in the North Atlantic regions and Canada, and to suggest further potential by analogy with these regions. Maps are significantly also lacking and three suitable examples are attached. Additions to the general map would be the areas examined and the extent of airborne radiometry. A further major omission is a definition of the meaning of potential resources, especially as 250,000 tonnes are claimed for the lujavrites at present and a future potential of 500,000 tonnes. I presume that this is the contained uranium which can be calculated as being present in the rock units, rather than any estimate of the amount of uranium which could be recovered economically. The figures for RAH and EAR at Kvanefjeld could conveniently be updated (Nov. 77) to RAH 15,750 t U, EAR 10,000 t U, TOTAL 25,750 t U. As these alkalic rocks are confined to the Garder province of the Ketilidian mobile belt some more definite indication of similar uraniferous types could be made from the excellent published maps and lead to more realistic estimates using the NURE formulae
International Nuclear Information System (INIS)
Xia Yuliang; Liu Hanbin; Lin Jinrong; Fan Guang; Hou Yanxian
2004-12-01
A method is developed for correcting uranium content in uranium ore samples by considering the U-Ra equilibrium coefficient, then a U-Pb isochron is drawn up. By performing the above correction ore-formation ages of sandstone-hosted uranium mineralization which may be more realistic have been obtained. The comparative research on U-Pb isotopic ages of detritic zircon in ore-hosting sandstone and zircon in intermediate-acid igneous rocks in corresponding provenance area indicates that the ore-hosting sandstone is originated from the erosion of intermediate-acid igneous rocks and the latters are the material basis for the formation of the uranium-rich sandstone beds. On the basis of the study on U-Pb isotopic system evolution of the provenance rocks and sandstones from ore-hosting series, it is verified that the uranium sources of the sandstone-hosted uranium deposit are: the intermediate-acid igneous rocks with high content of mobile uranium, and the sandstone bodies pre-concentrated uranium. (authors)
International Nuclear Information System (INIS)
Chaturvedi, Anand Kumar; Veldi, Ramesh Babu; Amulotu, Markandeyulu; Chaki, Anjan; Pavanaguru, R.
2015-01-01
Application of Geographical Information System (GIS) for identifying the spatial locations of uranium exploration target areas using multi-disciplinary geoscientific data is presented in this paper. The data sets used in this study are Airborne Gamma Ray Spectrometric (AGRS), Aeromagnetic (AM), Satellite images, regional ground gravity and geochemical surveys over one of the promising mobile Proterozoic Kunjar-Darjing Basins to the west of Singhbum Uranium Province (SUP), Odisha, India. Analysis of the geochemical data indicated unconformity related uranium mineralization along the unconformity between Kunjar-Darjing sediments and the S-type per-aluminous Tamparkola granite with labile uranium. All the data sets are processed and interpreted independently in terms of geology based on characteristics such as intensity, frequency and texture of the images generated. Various ratio maps generated from AGRS data were used as training points for spatial modeling by building relationships (topology) with the structures and geology interpreted from the magnetic and gravity datasets. Index overlay method is adapted in spatial modeling. The study shows that integrating the geological, geophysical, geochemical and other geodata in a GIS environment provides valuable guidelines for geological mapping as well as identifying target areas for uranium exploration. The GIS study facilitated in identifying potential target areas for uranium exploration along the regional faults D1 and D2 around the villages Kelo, Tarnra, northeast of Kunjar, Nuarali and Betajharan. (author)
Control of uranium hazards - Portsmouth uranium enrichment plant
International Nuclear Information System (INIS)
Wagner, E.R.
1985-01-01
This report summarizes the Environmental, Safety and Health programs to control uranium hazards at the Portsmouth Gaseous Diffusion Plant. A description of the physical plant, the facility processes and the attendant uranium flows and effluents are provided. The hazards of uranium are discussed and the control systems are outlined. Finally, the monitoring programs are described and summaries of recent data are provided. 11 figs., 20 tabs
International Nuclear Information System (INIS)
1987-01-01
Uranium industry data collected in the EIA-858 survey provide a comprehensive statistical characterization of annual activities of the industry and include some information about industry plans over the next several years. This report consists of two major sections. The first addresses uranium raw materials activities and covers the following topics: exploration activities and expenditures, resources and reserves, mine production of uranium, production of uranium concentrate, and industry employment. The second major section is concerned with the following uranium marketing activities: uranium purchase commitments, uranium prices, procurement arrangements, uranium imports and exports, enrichment services, inventories, secondary market activities utility market requirements and related topics
International Nuclear Information System (INIS)
Lawrence, M.S.S.
1985-01-01
This report provides a statistical description of activities of the US uranium industry during 1984 and includes a statistical profile of the status of the industry at the end of 1984. It is based on the results of an Energy Information Administration (EIA) survey entitled ''Uranium Industry Annual Survey'' (Form EIA-858). The principal findings of the survey are summarized under two headings - Uranium Raw Materials Activities and Uranium Marketing Activities. The first heading covers exploration and development, uranium resources, mine and mill production, and employment. The second heading covers uranium deliveries and delivery commitments, uranium prices, foreign trade in uranium, inventories, and other marketing activities. 32 figs., 48 tabs
Irradiated uranium reprocessing
International Nuclear Information System (INIS)
Gal, I.
1961-12-01
Task concerned with reprocessing of irradiated uranium covered the following activities: implementing the method and constructing the cell for uranium dissolving; implementing the procedure for extraction of uranium, plutonium and fission products from radioactive uranium solutions; studying the possibilities for using inorganic ion exchangers and adsorbers for separation of U, Pu and fission products
Aspects of uranium/thorium series disequilibrium applications to radionuclide migration studies
International Nuclear Information System (INIS)
Ivanovich, M.
1989-11-01
The aim of this paper is to consider the contribution which the uranium/thorium series disequilibrium concept can make to understanding the retardation and transport of radionuclides in the far-field of a radioactive waste repository. In principle, naturally occurring isotopes of uranium, thorium and radium can be regarded as geochemical analogues of the divalent radionuclides and multivalent actinides expected to be present in the radioactive waste inventory. The study of their retardation and/or transport in real rock/water systems which have taken place over geological timescales, can make an important contribution to establishing a rational basis for long-term predictive modelling of radionuclide transport required for safety assessments. (author)
International Nuclear Information System (INIS)
Anon.
1984-01-01
The article briefly discusses the Australian government policy and the attitude of political party factions towards the mining and exporting of the uranium resources in Australia. Australia has a third of the Western World's low-cost uranium resources
International Nuclear Information System (INIS)
Thompson, A.J.; Lehrenbaum, W.U.; Lashway, D.C.
2000-01-01
The US domestic uranium industry is at a crossroads. Historic low prices for uranium, combined with stringent and often irrational regulatory requirements, pose a very real threat to the industry's continued viability. The Nuclear Regulatory Commission has taken a number of innovative steps to reform and rationalize its regulatory program. However, if the domestic uranium recovery industry is to remain viable, additional steps toward innovation and reform are needed, and effective implementation of reforms adopted by the Commission is essential. (author)
International Nuclear Information System (INIS)
1999-01-01
The Uranium Industry Annual 1998 (UIA 1998) provides current statistical data on the US uranium industry's activities relating to uranium raw materials and uranium marketing. It contains data for the period 1989 through 2008 as collected on the Form EIA-858, ''Uranium Industry Annual Survey.'' Data provides a comprehensive statistical characterization of the industry's activities for the survey year and also include some information about industry's plans and commitments for the near-term future. Data on uranium raw materials activities for 1989 through 1998, including exploration activities and expenditures, EIA-estimated reserves, mine production of uranium, production of uranium concentrate, and industry employment, are presented in Chapter 1. Data on uranium marketing activities for 1994 through 2008, including purchases of uranium and enrichment services, enrichment feed deliveries, uranium fuel assemblies, filled and unfilled market requirements, and uranium inventories, are shown in Chapter 2. The methodology used in the 1998 survey, including data edit and analysis, is described in Appendix A. The methodologies for estimation of resources and reserves are described in Appendix B. A list of respondents to the ''Uranium Industry Annual Survey'' is provided in Appendix C. The Form EIA-858 ''Uranium Industry Annual Survey'' is shown in Appendix D. For the readers convenience, metric versions of selected tables from Chapters 1 and 2 are presented in Appendix E along with the standard conversion factors used. A glossary of technical terms is at the end of the report. 24 figs., 56 tabs
International Nuclear Information System (INIS)
Petit, J.
2009-06-01
To understand the transport mechanisms and the radionuclides behaviour in the bio-geosphere is necessary to evaluate healthy and environmental risks of nuclear industry. These mechanisms are monitored by radioelements speciation, namely the distribution between their different physico-chemical forms in the environment. From this perspective, this PhD thesis deals with uranium speciation in a natural background. A detailed summary of uranium biogeochemistry has been written, which enables to restrict the PhD issue to uranium complexation with oxalic acid, a hydrophilic organic acid with good binding properties, ubiquitous in soil waters. Analytical conditions have been established by means of speciation diagrams. The speciation diagrams building by means of literature stability constants has allowed to define the analytical conditions of complex formation. The chosen analytical technique is the hyphenation of a separative technique (liquid chromatography LC or capillary electrophoresis CE) with mass spectrometry (ICPMS). The studied complexes presence in the synthetic samples has been confirmed with UV/visible spectrophotometry. LC-ICPMS analyses have proved the lability of the uranyl-organic acid complexes, namely their tendency to dissociate during analysis, which prevents from studying uranium speciation. CE-ICPMS study of labile complexes from a metal-ligand system has been made possible by employing affinity capillary electrophoresis, which enables to determine stability constants and electrophoretic mobilities. This PhD thesis has allowed to compare the different mathematical treatments of binding isotherm and to take into account ionic strength and real ligand concentration. Affinity CE has been applied successfully to lanthanum-oxalate (model system) and uranium-oxalate systems. The obtained results have been applied to a real system (situated in Le Bouchet). This shows the contribution of the developed method to the modelling of uranium speciation. (author)
Preparation of uranium-230 as a new uranium tracer
International Nuclear Information System (INIS)
Hashimoto, T.; Kido, K.; Sotobayashi, T.
1977-01-01
A uranium isotope, 230 U(T=20.8 d), was produced from the 231 Pa(γ,n) 230 Pa→viaβ - decay 230 U process with a bremsstrahlung irradiation on a protactinium target. After standing for about one month to obtain a maximal growth of 230 U, the uranium was chemically purified, applying an ion-exchange method. The purity of the 230 U obtained was examined with alpha spectrometry and an intrinsic alpha peak due to 230 U as a new uranium tracer in an alpha spectrometric analysis of uranium isotopes is described. (author)
Synthesis of Uranium nitride powders using metal uranium powders
International Nuclear Information System (INIS)
Yang, Jae Ho; Kim, Dong Joo; Oh, Jang Soo; Rhee, Young Woo; Kim, Jong Hun; Kim, Keon Sik
2012-01-01
Uranium nitride (UN) is a potential fuel material for advanced nuclear reactors because of their high fuel density, high thermal conductivity, high melting temperature, and considerable breeding capability in LWRs. Uranium nitride powders can be fabricated by a carbothermic reduction of the oxide powders, or the nitriding of metal uranium. The carbothermic reduction has an advantage in the production of fine powders. However it has many drawbacks such as an inevitable engagement of impurities, process burden, and difficulties in reusing of expensive N 15 gas. Manufacturing concerns issued in the carbothermic reduction process can be solved by changing the starting materials from oxide powder to metals. However, in nitriding process of metal, it is difficult to obtain fine nitride powders because metal uranium is usually fabricated in the form of bulk ingots. In this study, a simple reaction method was tested to fabricate uranium nitride powders directly from uranium metal powders. We fabricated uranium metal spherical powder and flake using a centrifugal atomization method. The nitride powders were obtained by thermal treating those metal particles under nitrogen containing gas. We investigated the phase and morphology evolutions of powders during the nitriding process. A phase analysis of nitride powders was also a part of the present work
International Nuclear Information System (INIS)
Chen Yue; Yang Yaxin; Liu Qingcheng
2009-01-01
A measuring method of natural soil thermoluminescence is used for prospecting of uranium deposits. The better effects are obtained by using the method, but the parameters selected have significant effects on the intensity of soil thermoluminescent. So, the measuring parameters are selected according to the different soil samples. Based on the measuring 1 000 soil samples of granite type uranium deposit,the optimum heating up program of natural soil thermoluminescence is obtained, that is, preheating, lasting heating, constant temperature and the halting heating. The parameters selected are as follows: the heating rate being 15 degree C/s, the temperatures of the first and second constant temperature being 135 degree C and 400 degree C respectively. Using the selected parameters for measuring soil samples from a known mining area in Guangdong province, the result indicates that the abnormities of thermoluminescence have corresponding relations with the underground orebodies. (authors)
International Nuclear Information System (INIS)
Rubini, L.A.; Asem, M.A.D.
1990-01-01
The historical development of the uranium market is present in two periods: The initial period 1947-1970 and from 1970 onwards, with the establishment of a commercial market. The world uranium requirements are derived from the corresponding forecast of nuclear generating capacity, with, particular emphasis to the brazilian requirements. The forecast of uranium production until the year 2000 is presented considering existing inventories and the already committed demand. The balance between production and requirements is analysed. Finally the types of contracts currently being used and the development of uranium prices in the world market are considered. (author)
International Nuclear Information System (INIS)
McLemore, V.T.
1983-09-01
Over 1300 uranium and thorium occurrences are found in over 100 formational units in all but two counties, in all 1- by 2-degree topographic quadrangles, and in all four geographic provinces in New Mexico. Uranium production in New Mexico has surpassed yearly production from all other states since 1956. Over 200 mines in 18 counties in New Mexico have produced 163,010 tons (147,880 metric tons) of U 3 O 8 from 1948 to 1982, 40% of the total uranium production in the United States. More than 99% of this production has come from sedimentary rocks in the San Juan Basin area in northwestern New Mexico; 96% has come from the Morrison Formation alone. All of the uranium reserves and the majority of the potential uranium resources in New Mexico are in the Grants uranium district. About 112,500 tons (102,058 metric tons) of $30 per pound of U 3 O 8 reserves are in the San Juan Basin, about 55% of the total $30 reserves in the United States. Thorium reserves and resources in New Mexico have not been adequately evaluated and are unknown. Over 1300 uranium and thorium occurrences are described in this report, about 400 of these have been examined in the field by the author. The occurrence descriptions include information on location, commodities, production, development, geology, and classification. Over 1000 citations are included in the bibliography and referenced in the occurrence descriptions. Production statistics for uranium mines that operated from 1948 to 1970 are also included. Mines that operated after 1970 are classified into production categories. 43 figures, 9 tables
International Nuclear Information System (INIS)
Whillans, R.T.
1981-01-01
Events in the Canadian uranium industry during 1980 are reviewed. Mine and mill expansions and exploration activity are described, as well as changes in governmental policy. Although demand for uranium is weak at the moment, the industry feels optimistic about the future. (LL)
International Nuclear Information System (INIS)
Formiga, Thiago S.; Morais, Carlos A.; Gomiero, Luiz A.
2011-01-01
The uraniferous district of Lagoa Real, located in the south-central region of the state of Bahia, has reserves estimated at 100,000 tons of uranium, which is enough to supply Angra I, II and III for 100 more years. The process adopted for the beneficiation of the uranium ore from Lagoa Real is heap leaching, a static process in which the ore is crushed, disposed in heaps and irrigated with a sulfuric acid solution to remove the uranium. This technique has a relatively low cost of implementation, although the yield of uranium recovery is low, with an uranium content in the leached residue of 700 μg/g U 3 O 8 for ores with an initial content of 2,700 μg/g U 3 O 8 . With the deepening of the mine pit, an increase in the carbonate content in the ore was noted, which required a higher acid consumption in the leaching. In order to reduce the concentration of carbonates, a study of the ore concentration by flotation column was accomplished. The flotation reject had high carbonate content, with a uranium content of about 2,300 μg/g U 3 O 8 for flotation in one column and 1,100 μg/g U 3 O 8 for flotation in two columns. This paper presents the study of the leaching process for the recovery of the uranium present in the residue of the heap leaching and in the carbonated residue from the flotation of the anomaly 13 ore. The results indicate the feasibility of treating the waste of the heap leaching through dynamic leaching. The study of the uranium leaching from the flotation residue through acid leaching technique indicated a recovery of 96% of uranium, however with a high consumption of acid, around 450 kg/t, showing that for this case, the most suitable technique for the process is alkaline leaching. (author)
Energy Technology Data Exchange (ETDEWEB)
Formiga, Thiago S.; Morais, Carlos A., E-mail: cmorais@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Gomiero, Luiz A., E-mail: gomiero@inb.gov.b [Industrias Nucleares do Brasil S/A (INB), Caetite, BA (Brazil)
2011-07-01
The uraniferous district of Lagoa Real, located in the south-central region of the state of Bahia, has reserves estimated at 100,000 tons of uranium, which is enough to supply Angra I, II and III for 100 more years. The process adopted for the beneficiation of the uranium ore from Lagoa Real is heap leaching, a static process in which the ore is crushed, disposed in heaps and irrigated with a sulfuric acid solution to remove the uranium. This technique has a relatively low cost of implementation, although the yield of uranium recovery is low, with an uranium content in the leached residue of 700 {mu}g/g U{sub 3}O{sub 8} for ores with an initial content of 2,700 {mu}g/g U{sub 3}O{sub 8}. With the deepening of the mine pit, an increase in the carbonate content in the ore was noted, which required a higher acid consumption in the leaching. In order to reduce the concentration of carbonates, a study of the ore concentration by flotation column was accomplished. The flotation reject had high carbonate content, with a uranium content of about 2,300 {mu}g/g U{sub 3}O{sub 8} for flotation in one column and 1,100 {mu}g/g U{sub 3}O{sub 8} for flotation in two columns. This paper presents the study of the leaching process for the recovery of the uranium present in the residue of the heap leaching and in the carbonated residue from the flotation of the anomaly 13 ore. The results indicate the feasibility of treating the waste of the heap leaching through dynamic leaching. The study of the uranium leaching from the flotation residue through acid leaching technique indicated a recovery of 96% of uranium, however with a high consumption of acid, around 450 kg/t, showing that for this case, the most suitable technique for the process is alkaline leaching. (author)
International Nuclear Information System (INIS)
1986-11-01
This report consists of two major sections. The first addresses uranium raw materials activities and covers the following topics: exploration activities and expenditures, resources and reserves, mine production of uranium, production of uranium concentrate, and industry employment. The second major section is concerned with the following uranium marketing activities: uranium purchase commitments, uranium prices, procurement arrangements, uranium imports and exports, enrichment services, inventories, secondary market activities, utility market requirements, and related topics. A glossary and appendices are included to assist the reader in interpreting the substantial array of statistical data in this report and to provide background information about the survey
Chapter 1. General information about uranium. 1.3. Uranium ores
International Nuclear Information System (INIS)
Khakimov, N.; Nazarov, Kh.M.; Mirsaidov, I.U.
2012-01-01
The uranium ores were described. It was found that uranium ores and natural mineral formations containing uranium and its compounds, can be found in concentrations that are technically possible for industrial utilization and which are economically profitable. It was defined that oxidation levels of uranium minerals have an impact on their reprocessing technology and behavior in hydrometallurgical re partition. It was found that the chemical composition of ores has a decisive importance during selection of their reprocessing method.
International Nuclear Information System (INIS)
Hetland, Donald L.; Obellianne, Jean-marie
1981-04-01
The IUREP Orientation Phase Mission to Venezuela believes that the Speculative Uranium Resources of that country fall between 2,000 and 42,000 tonnes. This assumes that a part of the Speculative Resources would be extracted as by-product uranium from wet-process phosphoric acid production. Past exploration in Venezuela has resulted in the discovery of very few uranium occurrences and radioactive anomalies except for the many airborne anomalies recorded on the Guayana Shield. To date no economic deposits or significant uranium occurrences have been found in Venezuela except for the uraniferous phosphorites in the Cretaceous Navey Formation which are very low grade. The uranium occurrences and radioactive anomalies can be divided according to host rock into: (1) Precambrian crystalline and sedimentary rocks, (2) Cretaceous phosphorite beds, (3) continental sandstone, and (4) granitic rocks. The greatest geological potential for further uranium resources is believed to exist in the crystalline and sedimentary Precambrian rocks of the Guayana Shield, but favorable geological potential also exist in younger continental sandstones. Since the Guayana Shield is the most promising for the discovery of economic uranium deposits most of the proposed exploration effort is directed toward that area. Considerable time, effort and capital will be required however, because of the severe logistical problems of exploration in this vast, rugged and inaccessable area, Meager exploration work done to date has been relatively negative suggesting the area is more of a thorium rather than a uranium province. However because of the possibility of several types of uranium deposits and because so little exploration work has been done, the Mission assigned a relatively small speculative potential to the area, i.e. 0 to 25,000 tonnes uranium. A small speculative potential (0 to 2,000 tonnes) was assigned to the El Baul area in Cojedes State, in the Llanos Province. This potential is postulated
Uranium production in thorium/denatured uranium fueled PWRs
International Nuclear Information System (INIS)
Arthur, W.B.
1977-01-01
Uranium-232 buildup in a thorium/denatured uranium fueled pressurized water reactor, PWR(Th), was studied using a modified version of the spectrum-dependent zero dimensional depletion code, LEOPARD. The generic Combustion Engineering System 80 reactor design was selected as the reactor model for the calculations. Reactors fueled with either enriched natural uranium and self-generated recycled uranium or uranium from a thorium breeder and self-generated recycled uranium were considered. For enriched natural uranium, concentrations of 232 U varied from about 135 ppM ( 232 U/U weight basis) in the zeroth generation to about 260 ppM ( 232 U/U weight basis) at the end of the fifth generation. For the case in which thorium breeder fuel (with its relatively high 232 U concentration) was used as reactor makeup fuel, concentrations of 232 U varied from 441 ppM ( 232 U/U weight basis) at discharge from the first generation to about 512 ppM ( 232 U/U weight basis) at the end of the fifth generation. Concentrations in freshly fabricated fuel for this later case were 20 to 35% higher than the discharge concentration. These concentrations are low when compared to those of other thorium fueled reactor types (HTGR and MSBR) because of the relatively high 238 U concentration added to the fuel as a denaturant. Excellent agreement was found between calculated and existing experimental values. Nevertheless, caution is urged in the use of these values because experimental results are very limited, and the relevant nuclear data, especially for 231 Pa and 232 U, are not of high quality
Derived enriched uranium market
International Nuclear Information System (INIS)
Rutkowski, E.
1996-01-01
The potential impact on the uranium market of highly enriched uranium from nuclear weapons dismantling in the Russian Federation and the USA is analyzed. Uranium supply, conversion, and enrichment factors are outlined for each country; inventories are also listed. The enrichment component and conversion components are expected to cause little disruption to uranium markets. The uranium component of Russian derived enriched uranium hexafluoride is unresolved; US legislation places constraints on its introduction into the US market
Uranium ores of Kazakhstan as the most technologic source of a fissionable material
International Nuclear Information System (INIS)
Berikbolov, B.R.
1999-01-01
Kazakhstan as is known has unique deposits of uranium. Its resources composed a third part of the world resources. The most important part of resources having a practical value, is related with depression in southern regions of the Republic. By now more than 15 deposits are discovered and partially explored. These deposits from three uranium provinces - Shu-Sarysu, Syr-Darya and Ili. The ores occur in friable water-bearing sandy horizons of Cretaceous and Paleogene age between waterproof agrillaceous sediments at depth from 100 up to 600 m. Ore bodies thickness changes from 5 to 10 m at uranian average-grade 0.03-0.1 %. Width of band shaped ore bodies changes from tens meters to the one kilometers and extent changes from one kilometer up to many tens kilometers. The important feature of deposits is their suitability for development by progressive in situ leaching (ISL) method. It was demonstrated, that uranium ores are comprehensive and, that is important, a lot of commercially important elements, containing in ores, gives in to extraction at development by the ISL method. The preliminary calculation of expenditures for the extraction of useful byproducts from ordinary sulphate solution have demonstrated rather high profitableness for rhenium, scandium, selenium, rare earth even at the very low contents in solution. It was pointed out, that whole technological chain applied now at industrial scale is oriented to mono-metallic uranium ores, therefore present technology of leaching and recovery of industrial solution does not allow ti extract all valuable components containing in ores. The development of new improved technological chain. beginning with a composition of leaching out reagent and up to applying of miscellaneous sorbing materials, can create new mineral-raw base of rare and dissipated elements and to lower considerably the price of uranium mining from sandstone deposits
Equations of state for enriched uranium and uranium alloy to 3500 MPa
International Nuclear Information System (INIS)
Bai Chaomao; Hai Yuying; Liu Jenlong; Li Zhenrong
1990-04-01
The volume compressions of 6 kinds of cast materials including enriched uranium, poor uranium, U-0.57 wt% Ti, U-0.33 wt% Nb, U-2.85 wt% Nb and U-7.5 wt% Nb-3.3 wt% Zr have been determined by monitoring piston displacements in a piston cylinder apparatus with double strengthening rings to 3500 MPa at room temperature. The dilation of the cylinder vessel and the press deformation were corrected by some experiments. The calculational data free from using the standard sample closed with used standard sample. The volume compressions of enriched uranium and poor uranium are nearly coincident. Pure uranium is more compressible than uranium alloys. These values of enriched uranium are in close agreement with values of Bridgman's pure uranium. The fitting coefficients of Bridgman's polynomial and Anderson's equation of state and isothermal bulk modules for the above materials are given
International Nuclear Information System (INIS)
Almeida, Geangela M.; Souza, Susana O.; Campos, Simara S.S.; Gennari, Roseli F.
2011-01-01
The economic growing in Brazil is responsible for an urgent demand for energy. Uranium is the fuel used to generate nuclear power. Brazil has the sixth largest reserve of the uranium ore in the world and, nowadays there is only one mine under exploration (Uraniferous District of Lagoa Real - Caetite-BA). Some Non-Governmental Organizations (NGOs), such as Greenpeace, state that the explored uranium mine is dangerous and polluting, causing water contamination by uranium. So, the population would be receiving radiation doses above permissible limits. However, Industrias Nucleares do Brasil (INB) the company in charge of the complex extraction and production of yellow cake rejected these accusations. The main purpose of this work is the determination of the composition of natural radionuclides in the Uraniferous District of Lagoa Real in order to determine if the nearest population is exposed to environmental radiation. It was checked if there is water contamination due to the natural transport in the uranium mining surroundings. Soil and water samples from Caetite mine and also from nearby town were collected. Only one water sample collected had concentrations higher than the limits recommended by World Health Organization. The presence of radionuclides in soil samples is considered independent of mineral exploration. The effective dose rates in almost all samples are above the world average which is 2.4 mSv/y. To sum up, the presence of uranium in water and soil of the tested areas is probably due to the nature of the soil and not to the exploration of mine. (author)
Energy Technology Data Exchange (ETDEWEB)
Almeida, Geangela M.; Souza, Susana O. [Federal University of Sergipe (UFS), Sao Cristovao, SE (Brazil). Dept. of Physics; Campos, Simara S.S. [State University of Southwest Bahia (UESB), Itapetinga, BA (Brazil). Dept. of Basic and Instrumental Studies; Gennari, Roseli F., E-mail: rgennari@dfn.if.usp.b [University of Sao Paulo (USP), Sao Paulo, SP (Brazil). Inst. of Physics. Dept. of Nuclear Physics
2011-07-01
The economic growing in Brazil is responsible for an urgent demand for energy. Uranium is the fuel used to generate nuclear power. Brazil has the sixth largest reserve of the uranium ore in the world and, nowadays there is only one mine under exploration (Uraniferous District of Lagoa Real - Caetite-BA). Some Non-Governmental Organizations (NGOs), such as Greenpeace, state that the explored uranium mine is dangerous and polluting, causing water contamination by uranium. So, the population would be receiving radiation doses above permissible limits. However, Industrias Nucleares do Brasil (INB) the company in charge of the complex extraction and production of yellow cake rejected these accusations. The main purpose of this work is the determination of the composition of natural radionuclides in the Uraniferous District of Lagoa Real in order to determine if the nearest population is exposed to environmental radiation. It was checked if there is water contamination due to the natural transport in the uranium mining surroundings. Soil and water samples from Caetite mine and also from nearby town were collected. Only one water sample collected had concentrations higher than the limits recommended by World Health Organization. The presence of radionuclides in soil samples is considered independent of mineral exploration. The effective dose rates in almost all samples are above the world average which is 2.4 mSv/y. To sum up, the presence of uranium in water and soil of the tested areas is probably due to the nature of the soil and not to the exploration of mine. (author)
International Nuclear Information System (INIS)
1985-09-01
In 1974 the Minister of Energy, Mines and Resources (EMR) established a Uranium Resource Appraisal Group (URAG) within EMR to audit annually Canada's uranium resources for the purpose of implementing the federal government's uranium export policy. A major objective of this policy was to ensure that Canadian uranium supplies would be sufficient to meet the needs of Canada's nuclear power program. As projections of installed nuclear power growth in Canada over the long term have been successively revised downwards (the concern about domestic security of supply is less relevant now than it was 10 years ago) and as Canadian uranium supply capabilities have expanded significantly. Canada has maintained its status as the western world's leading exporter of uranium and has become the world's leading producer. Domestic uranium resource estimates have increased to 551 000 tonnes U recoverable from mineable ore since URAG completed its last formal assessment (1982). In 1984, Canada's five primary uranium producers employed some 5800 people at their mining and milling operations, and produced concentrates containing some 11 170 tU. It is evident from URAG's 1984 assessment that Canada's known uranium resources, recoverable at uranium prices of $150/kg U or less, are more than sufficient to meet the 30-year fuelling requirements of those reactors that are either in opertaion now or committed or expected to be in-service by 1995. A substantial portion of Canada's identified uranium resources, recoverable within the same price range, is thus surplus to Canadian needs and available for export. Sales worth close to $1 billion annually are assured. Uranium exploration expenditures in Canada in 1983 and 1984 were an estimated $41 million and $35 million, respectively, down markedly from the $128 million reported for 1980. Exploration drilling and surface development drilling in 1983 and 1984 were reported to be 153 000 m and 197 000 m, respectively, some 85% of which was in
International Nuclear Information System (INIS)
Zhang Jianguo; Chen Shaoqiang; Qi Jing
2002-01-01
Developing macroporous resin for purifying uranium effluent from uranium mining and metallurgy is presented. The Intense Fractionation Process is employed to elute uranium from lower loaded uranium resin by the eluent of sulfuric acid and ammonium sulfate. The result is indicated that the uranium concentration in the rich elutriant is greatly increased, and the rich liquor is only one bed column volume, uranium concentration in the elutriant is increased two times which concentration is 10.1 g/L. The eluent is saved about 50% compared with the conventional fixed bed elution operation. And also the acidity in the rich elutriant is of benefit to the later precipitation process in uranium recovery
Recycling of reprocessed uranium
International Nuclear Information System (INIS)
Randl, R.P.
1987-01-01
Since nuclear power was first exploited in the Federal Republic of Germany, the philosophy underlying the strategy of the nuclear fuel cycle has been to make optimum use of the resource potential of recovered uranium and plutonium within a closed fuel cycle. Apart from the weighty argument of reprocessing being an important step in the treatment and disposal of radioactive wastes, permitting their optimum ecological conditioning after the reprocessing step and subsequent storage underground, another argument that, no doubt, carried weight was the possibility of reducing the demand of power plants for natural uranium. In recent years, strategies of recycling have emerged for reprocessed uranium. If that energy potential, too, is to be exploited by thermal recycling, it is appropriate to choose a slightly different method of recycling from the one for plutonium. While the first generation of reprocessed uranium fuel recycled in the reactor cuts down natural uranium requirement by some 15%, the recycling of a second generation of reprocessed, once more enriched uranium fuel helps only to save a further three per cent of natural uranium. Uranium of the second generation already carries uranium-232 isotope, causing production disturbances, and uranium-236 isotope, causing disturbances of the neutron balance in the reactor, in such amounts as to make further fabrication of uranium fuel elements inexpedient, even after mixing with natural uranium feed. (orig./UA) [de
International Nuclear Information System (INIS)
Kenward, M.
1976-01-01
Comment is made on the latest of a series of reports on world uranium resources from the OECD's Nuclear Energy Agency and the UN's International Atomic Energy Agency (Uranium resources, production and demand (including other nuclear fuel cycle data), published by the Organisation for Economic Cooperation and Development, Paris). The report categories uranium reserves by their recovery cost and looks at power demand and the whole of the nuclear fuel cycle, including uranium enrichment and spent fuel reprocessing. The effect that fluctuations in uranium prices have had on exploration for new uranium resources is considered. It is stated that increased exploration is essential considering the long lead times involved but that thanks to today's higher prices there are distinct signs that prospecting activities are increasing again. (U.K.)
Uranium demand, supply and prices, 1991-2000: a report to Greenpeace
International Nuclear Information System (INIS)
O'Faircheallaigh, C.
1990-01-01
Taking account of recent developments in relation to existing nuclear power plants and applying realistic schedules to new developments, this study has calculated estimates of future nuclear power plant capacity which are slightly lower than other published forecasts for 1996, and significantly lower (by between 7 and 9 per cent) than other forecasts for 2000. This data was then used to calculate demand for newly-mined uranium in each year from 1991 to 2000. Detailed data relating to some 40 existing uranium mines and twenty planned projects to estimate supply during the same period, have also been analysed. Combining the estimates for supply and demand, the study forecasts a small shortfall in supply during 1991-1995. However, this shortfall can be covered by a slight reduction in the uranium stocks which will exist at that time and, on the basis of experience during recent years, it is unlikely to result in more than a modest increase in prices. Supply is expected to significantly exceed demand from 1996-1998, and to slightly exceed demand in 1999-2000. This is likely to exert downward pressure on uranium prices, keeping them close to their current low levels in real terms. This information is then used to gauge the economic prospects for development of new uranium mining capacity in Australia between now and the end of the century. 18 refs., 6 tabs
International Nuclear Information System (INIS)
Smirnov, A Yu; Sulaberidze, G A; Dudnikov, A A; Nevinitsa, V A
2016-01-01
The possibility of the recovered uranium enrichment in a cascade of gas centrifuges with three feed flows (depleted uranium, low-enriched uranium, recovered uranium) with simultaneous dilution of U-232,234,236 isotopes was shown. A series of numerical experiments were performed for different content of U-235 in low-enriched uranium. It has been demonstrated that the selected combination of diluents can simultaneously reduce the cost of separative work and the consumption of natural uranium, not only with respect to the previously used multi-flow cascade schemes, but also in comparison to the standard cascade for uranium enrichment. (paper)
International Nuclear Information System (INIS)
Anon.
1983-01-01
Recent decisions by the Australian Government will ensure a significant expansion of the uranium industry. Development at Roxby Downs may proceed and Ranger may fulfil two new contracts but the decision specifies that apart from Roxby Downs, no new mines should be approved. The ACTU maintains an anti-uranium policy but reaction to the decision from the trade union movement has been muted. The Australian Science and Technology Council (ASTEC) has been asked by the Government to conduct an inquiry into a number of issues relating to Australia's role in the nuclear fuel cycle. The inquiry will examine in particular Australia's nuclear safeguards arrangements and the adequacy of existing waste management technology. In two additional decisions the Government has dissociated itself from a study into the feasibility of establishing an enrichment operation and has abolished the Uranium Advisory Council. Although Australian reserves account for 20% of the total in the Western World, Australia accounts for a relatively minor proportion of the world's uranium production
New french uranium mineral species
International Nuclear Information System (INIS)
Branche, G.; Chervet, J.; Guillemin, C.
1952-01-01
In this work, the authors study the french new uranium minerals: parsonsite and renardite, hydrated phosphates of lead and uranium; kasolite: silicate hydrated of uranium and lead uranopilite: sulphate of uranium hydrated; bayleyite: carbonate of uranium and of hydrated magnesium; β uranolite: silicate of uranium and of calcium hydrated. For all these minerals, the authors give the crystallographic, optic characters, and the quantitative chemical analyses. On the other hand, the following species, very rare in the french lodgings, didn't permit to do quantitative analyses. These are: the lanthinite: hydrated uranate oxide; the α uranotile: silicate of uranium and of calcium hydrated; the bassetite: uranium phosphate and of hydrated iron; the hosphuranylite: hydrated uranium phosphate; the becquerelite: hydrated uranium oxide; the curite: oxide of uranium and lead hydrated. Finally, the authors present at the end of this survey a primary mineral: the brannerite, complex of uranium titanate. (author) [fr
Recovery of Uranium from Seawater: Modified Polyacrylonitrile Fibers as Selective Extractants
Energy Technology Data Exchange (ETDEWEB)
Alexandratos, Spiro D. [City Univ. (CUNY), NY (United States)
2017-03-15
A new bifunctional fiber has been prepared and found to have a significant loading capacity of uranium from real seawater. The fiber support is polyacrylonitrile and bifunctionality is provided by amidoxime and either diethylenetriamine (DETA) or ethylenediamine (EDA) ligands. The key feature is adjusting the hydrophilic /lipophilic balance within the fiber and this was best accomplished by partially acetylating or carboxylating EDA ligands. The bifunctional carboxylated EDA /AO fiber had a loading capacity of 3.83 mg U/g fiber at the Pacific Northwest National Laboratory with a 21 day contact time in real seawater.
Why can rossing uranium mine keep mining even in low price conditions of uranium market
International Nuclear Information System (INIS)
Tan Chenglong
2004-01-01
Rossing uranium mine is the only operating uranium mine in the world where the uranium occurs in intrusive alaskite. In the past 10 years, uranium market regressed in the world, uranium production weakened, expenditures of capital for uranium exploration were insufficient. Uranium spot market price rapidly decreased from $111.8/kg U in late 1970's to $22.1/kg U in mid-1990's. Why can Rossing uranium mine mined with traditional underground and open pit operation can keep running even in low price conditions of uranium market? Augumenting research on the deposit, mineral and technology, decreasing production cost and improving selling strategy can not only maintain Rossing's uranium production at present, but also ensure sustainable development in the coming 15 years. Exploration of low-costed uranium deposits is very important. However, obvious economic benefits can be obtained, as Rossing uranium mine does, by augumenting geological-economical research on the known uranium deposits of hard-rock type and by using new techniques to improve the conventional techniques in the uranium mine development. (authors)
Geochemical exploration for uranium
International Nuclear Information System (INIS)
Rose, A.W.
1977-01-01
The processes and types of dispersion that produce anomalies in stream water, stream sediment, and ground water, and the factors that must be considered in planning and interpreting geochemical surveys are reviewed. Examples of surveys near known deposits show the types of results to be expected. Background values depend mainly on the content of U in rocks of the drainage area. In igneous rocks, U tends to increase with potassium from ultramafic rocks (0.01 ppM) to granitic rocks (1 to 5 ppM). Some alkalic rocks have unusually high contents of U (15 to 100 ppM). Uranium-rich provinces marked by igneous rocks unusually rich in U are recognized in several areas and appear to have a deep crustal or mantle origin. In western U.S., many tertiary tuffaceous rocks have a high U content. Sandstones, limestones, and many shales approximate the crustal abundance at 0.5 to 4 ppM, but black shales, phosphates, and some organic materials are notably enriched in U. Uranium is very soluble in most oxidizing waters at the earth's surface, but is precipitated by reducing agents (organic matter, H 2 S) and adsorbed by organic material and some Fe oxides. In most surface and ground waters, U correlates approximately with the total dissolved solids, conductivity, and bicarbonate concentration of the water, and with the U content of rocks it comes into contact with. Most surveys of stream water near known districts show distinct anomalies extending a few km to tens of km downstream. A complication with water is the large variability with time, up to x 50, as a result of changes in the ratio of ground water to direct runoff, and changes in rate of oxidation and leaching. Collection and analysis of water samples also pose some difficulties
International Nuclear Information System (INIS)
Grey, T.; Gaul, J.; Crooks, P.; Robotham, R.
1980-01-01
Opposing viewpoints on the future role of uranium are presented. Topics covered include the Australian Government's uranium policy, the status of nuclear power around the world, Australia's role as a uranium exporter and problems facing the nuclear industry
International Nuclear Information System (INIS)
Goldschmidt, B.
1990-01-01
The bicentenary of the discovery of uranium coincides with the fiftieth anniversary of the discovery of fission, an event of worldwide significance and the last episode in the uranium -radium saga which is the main theme of this paper. Uranium was first identified by the German chemist Martin Klaproth in 1789. He extracted uranium oxide from the ore pitchblende which was a by-product of the silver mines at Joachimsthal in Bohemia. For over a century after its discovery, the main application for uranium derived from the vivid colours of its oxides and salts which are used in glazes for ceramics, and porcelain. In 1896, however, Becquerel discovered that uranium emitted ionizing radiation. The extraction by Pierre and Marie Curie of the more radioactive radium from uranium in the early years of the twentieth century and its application to the treatment of cancer shifted the chief interest to radium production. In the 1930s the discovery of the neutron and of artificial radioactivity stimulated research in a number of European laboratories which culminated in the demonstration of fission by Otto Frisch in January 1939. The new found use of uranium for the production of recoverable energy, and the creation of artificial radioelements in nuclear reactors, eliminated the radium industry. (author)
International Nuclear Information System (INIS)
Roche, P.
1993-01-01
During the uranium enrichment process required to make nuclear weapons or fuel, the concentration of the 'fissile' U-235 isotope has to be increased. What is left, depleted uranium, is about half as radioactive as natural uranium, but very dense and extremely hard. It is used in armour piercing shells. External radiation levels from depleted uranium (DU) are low. However DU is about as toxic as lead and could be harmful to the kidneys if eaten or inhaled. It is estimated that between 40 and 300 tonnes of depleted uranium were left behind by the Allied armies after the Gulf war. The biggest hazard would be from depleted uranium shells which have hit Iraqui armoured vehicles and the resulting dust inhaled. There is a possible link between depleted uranium shells and an illness known as 'Desert Storm Syndrome' occurring in some Gulf war veterans. As these shells are a toxic and radioactive hazard to health and the environment their use and testing should be stopped because of the risks to troops and those living near test firing ranges. (UK)
International Nuclear Information System (INIS)
1989-01-01
GAO was asked to address several questions concerning a number of proposed uranium enrichment bills introduced during the 100th Congress. The bill would have restructured the Department of Energy's uranium enrichment program as a government corporation to allow it to compete more effectively in the domestic and international markets. Some of GAO's findings discussed are: uranium market experts believe and existing market models show that the proposed DOE purchase of a $750 million of uranium from domestic producers may not significantly increase production because of large producer-held inventories; excess uranium enrichment production capacity exists throughout the world; therefore, foreign producers are expected to compete heavily in the United States throughout the 1990s as utilities' contracts with DOE expire; and according to a 1988 agreement between DOE's Offices of Nuclear Energy and Defense Programs, enrichment decommissioning costs, estimated to total $3.6 billion for planning purposes, will be shared by the commercial enrichment program and the government
International Nuclear Information System (INIS)
1976-01-01
This is a press release issued by the OECD on 9th March 1976. It is stated that the steep increases in demand for uranium foreseen in and beyond the 1980's, with doubling times of the order of six to seven years, will inevitably create formidable problems for the industry. Further substantial efforts will be needed in prospecting for new uranium reserves. Information is given in tabular or graphical form on the following: reasonably assured resources, country by country; uranium production capacities, country by country; world nuclear power growth; world annual uranium requirements; world annual separative requirements; world annual light water reactor fuel reprocessing requirements; distribution of reactor types (LWR, SGHWR, AGR, HWR, HJR, GG, FBR); and world fuel cycle capital requirements. The information is based on the latest report on Uranium Resources Production and Demand, jointly issued by the OECD's Nuclear Energy Agency (NEA) and the International Atomic Energy Agency. (U.K.)
International Nuclear Information System (INIS)
Silver, J.M.; Wright, W.J.
1976-01-01
The world resources of uranium and the future demand for uranium are discussed. The amount of uranium available depends on the price which users are prepared to pay for its recovery. As the price is increased, there is an incentive to recover uranium from lower grade or more difficult deposits. In view of this, attention is drawn to the development of the uranium industry in Australias
Uranium isotopes determination in urine samples using alpha spectrometry and ICP-MS
International Nuclear Information System (INIS)
Rosa, Mychelle M.L.; Maihara, Vera A.; Tine, Fernanda D.; Santos, Sandra M.C.; Bonifacio, Rodrigo L.; Taddei, Maria HelenaT.
2015-01-01
The action of determining the concentration of uranium isotopes in biological samples, 'in vitro' bioassay, is an indirect method for evaluating the incorporation and quantification of these radionuclides internally deposited. When incorporated, these radionuclides tend to be disposed through excretion, with urine being the main source of data because it can be easily collected and analyzed. The most widely used methods for determination of uranium isotopes ( 234 U, 235 U and 238 U) are Alpha Spectrometry and ICP-MS. This work presents a comparative study for the determination of uranium isotopes using these two methodologies in real samples from occupationally exposed workers. In order to validate the methodology, a sample of the intercomparison exercise organized by PROCORAD (Association pour la Promotion du Controle de Qualite des Analyses de Biologie Medicale em Radiotoxicologie) was used, and the results were statistically compared applying the Student's t-test. (author)
Cellular localization of uranium in the renal proximal tubules during acute renal uranium toxicity.
Homma-Takeda, Shino; Kitahara, Keisuke; Suzuki, Kyoko; Blyth, Benjamin J; Suya, Noriyoshi; Konishi, Teruaki; Terada, Yasuko; Shimada, Yoshiya
2015-12-01
Renal toxicity is a hallmark of uranium exposure, with uranium accumulating specifically in the S3 segment of the proximal tubules causing tubular damage. As the distribution, concentration and dynamics of accumulated uranium at the cellular level is not well understood, here, we report on high-resolution quantitative in situ measurements by high-energy synchrotron radiation X-ray fluorescence analysis in renal sections from a rat model of uranium-induced acute renal toxicity. One day after subcutaneous administration of uranium acetate to male Wistar rats at a dose of 0.5 mg uranium kg(-1) body weight, uranium concentration in the S3 segment of the proximal tubules was 64.9 ± 18.2 µg g(-1) , sevenfold higher than the mean renal uranium concentration (9.7 ± 2.4 µg g(-1) ). Uranium distributed into the epithelium of the S3 segment of the proximal tubules and highly concentrated uranium (50-fold above mean renal concentration) in micro-regions was found near the nuclei. These uranium levels were maintained up to 8 days post-administration, despite more rapid reductions in mean renal concentration. Two weeks after uranium administration, damaged areas were filled with regenerating tubules and morphological signs of tissue recovery, but areas of high uranium concentration (100-fold above mean renal concentration) were still found in the epithelium of regenerating tubules. These data indicate that site-specific accumulation of uranium in micro-regions of the S3 segment of the proximal tubules and retention of uranium in concentrated areas during recovery are characteristics of uranium behavior in the kidney. Copyright © 2015 John Wiley & Sons, Ltd.
The uranium in the environment; L'uranium dans l'environnement
Energy Technology Data Exchange (ETDEWEB)
NONE
2001-07-01
The uranium is a natural element omnipresent in the environment, with a complex chemistry more and more understood. Many studies are always today devoted to this element to better improve the uranium behavior in the environment. To illustrate this knowledge and for the public information the CEA published this paper. It gathers in four chapters: historical aspects and properties of the uranium, the uranium in the environment and the impacts, the metrology of the uranium and its migration. (A.L.B.)
International Nuclear Information System (INIS)
Anon.
1990-01-01
When NUEXCO was organized in 1968, its founders conceived of a business based on uranium loans. The concept was relatively straightforward; those who found themselves with excess supplies of uranium would deposit those excesses in NUEXCO's open-quotes bank,close quotes and those who found themselves temporarily short of uranium could borrow from the bank. The borrower would pay interest based on the quantity of uranium borrowed and the duration of the loan, and the bank would collect the interest, deduct its service fee for arranging the loan, and pay the balance to those whose deposits were borrowed. In fact, the original plan was to call the firm Nuclear Bank Corporation, until it was discovered that using the word open-quotes Bankclose quotes in the name would subject the firm to various US banking regulations. Thus, Nuclear Bank Corporation became Nuclear Exchange Corporation, which was later shortened to NUEXCO. Neither the nuclear fuel market nor NUEXCO's business developed quite as its founders had anticipated. From almost the very beginning, the brokerage of uranium purchases and sales became a more significant activity for NUEXCO than arranging uranium loans. Nevertheless, loan transactions have played an important role in the international nuclear fuel market, requiring the development of special knowledge and commercial techniques
Uranium isotopes in groundwater: their use in prospecting for sandstone-type uranium deposits
International Nuclear Information System (INIS)
Cowart, J.B.; Osmond, J.K.
1977-01-01
The relative abundances of dissolved 238 U and its daughter 234 U appear to be greatly affected as the uranium is transported downdip in sandstone aquifers. In an actively forming uranium accumulation at a reducing barrier, an input of 234 U occurs in proximity to the isotopically non-selective precipitation of uranium from the water. The result is a downdip water much lower in uranium concentration but relatively enriched in 234 U. The measurement of isotopic as well as concentration changes may increase the effectiveness of hydrogeochemical exploration of uranium. The investigation includes the uranium isotopic patterns in aquifers associated with known uranium orebodies in the Powder River and Shirley Basins, Wyoming, and Karnes County, Texas, USA. In addition, the Carrizo sandstone aquifer of Texas was studied in detail and the presence of an uranium accumulation inferred
International Uranium Resources Evaluation Project (IUREP) national favourability studies: Argentina
International Nuclear Information System (INIS)
1977-08-01
Argentina is a predominantly lowland area of 2,789,240 square kilometers. The capital is Buenos Aires. The entire length of Argentina is bordered on the west by the Andes Mountains. Tile Northwest Andes-Piedmont region consists of deep valleys containing salt basins and volcanoes, and is an earthquake zone. Patagonia, in the south, is essentially an arid region of windy plateaus and valleys. The southern Andes are narrower and lower than the northern Andes and in the extreme south contain glaciers and ice fields. The east-central plain (Pampa) of Argentina has dry and humid sectors and contains most of the population. The largest rivers are chiefly in the northeast, many having only seasonal flow. There has been extensive surface and subsurface exploration for uranium in Argentina for over 20 years. Although most of the work has been performed by the CNEA, advisors from the U.S. and from the IAEA have also taken part. Private industry has been involved, but apparently only on a small scale. In the OECD report of 1970, it was stated that 400,000 square kilometers of Argentina appear very favorable for uranium while an additional 900,000 square kilometers offer fair possibilities. Uranium exploration to date suggests that sandstones of Permian and Cretaceous ages exposed in Western Argentina in the Cordillera are very promising for discovery of new deposits. Past CNEA estimates have indicated that there is considerable hope for new discoveries in those areas where reserves are now known. In addition to the known uraniferous provinces which are indeed favorable for further exploration, there are several other large areas that warrant attention. There are, for example, in the Santa Cruz area of about 15,500 square kilometers Cretaceous and Tertiary sediments with favorable facies for uranium deposition. In the Patagonia Cordillera, Jurassic, Cretaceous, and Tertiary sediments are of interest for prospecting, These rocks contain carbonaceous material and have been
International Nuclear Information System (INIS)
Capus, G.; Arnold, Th.
2004-01-01
The controversy about the extend of the uranium resources worldwide is still important, this article sheds some light on this topic. Every 2 years IAEA and NEA (nuclear energy agency) edit an inventory of uranium resources as reported by contributing countries. It appears that about 4.6 millions tons of uranium are available at a recovery cost less than 130 dollars per kg of uranium and a total of 14 millions tons of uranium can be assessed when including all existing or supposed resources. In fact there is enough uranium to sustain a moderate growth of the park of nuclear reactors during next decades and it is highly likely that the volume of uranium resources can allow a more aggressive development of nuclear energy. It is recalled that a broad use of the validated breeder technology can stretch the durability of uranium resources by a factor 50. (A.C.)
Training manual for uranium mill workers on health protection from uranium
International Nuclear Information System (INIS)
McElroy, N.; Brodsky, A.
1986-01-01
This report provides information for uranium mill workers to help them understand the radiation safety aspects of working with uranium as it is processed from ore to yellowcake at the mills. The report is designed to supplement the radiation safety training provided by uranium mills to their workers. It is written in an easily readable style so that new employees with no previous experience working with uranium or radiation can obtain a basic understanding of the nature of radiation and the particular safety requirements of working with uranium. The report should be helpful to mill operators by providing training material to support their radiation safety training programs
Development of an on-line analyzer for organic phase uranium concentration in extraction process
International Nuclear Information System (INIS)
Dong Yanwu; Song Yufen; Zhu Yaokun; Cong Peiyuan; Cui Songru
1998-10-01
The working principle, constitution, performance of an on-line analyzer and the development characteristic of immersion sonde, data processing system and examination standard are reported. The performance of this instrument is reliable. For identical sample, the signal fluctuation in continuous monitoring for four months is less than +-1%. According to required measurement range by choosing appropriate length of sample cell the precision of measurement is better than 1% at uranium concentration 100 g/L. The detection limit is (50 +- 10) mg/L. The uranium concentration in process stream can be automatically displayed and printed out in real time and 4∼20 mA current signal being proportional to the uranium concentration can be presented. So the continuous control and computer management for the extraction process can be achieved
Uranium/plutonium and uranium/neptunium separation by the Purex process using hydroxyurea
International Nuclear Information System (INIS)
Zhu Zhaowu; He Jianyu; Zhang Zefu; Zhang Yu; Zhu Jianmin; Zhen Weifang
2004-01-01
Hydroxyurea dissolved in nitric acid can strip plutonium and neptunium from tri-butyl phosphate efficiently and has little influence on the uranium distribution between the two phases. Simulating the 1B contactor of the Purex process by hydroxyurea with nitric acid solution as a stripping agent, the separation factors of uranium/plutonium and uranium/neptunium can reach values as high as 4.7 x 10 4 and 260, respectively. This indicates that hydroxyurea is a promising salt free agent for uranium/plutonium and uranium/neptunium separations. (author)
International Nuclear Information System (INIS)
Tucker, H.L.; McElhaney, R.J.
1983-01-01
A simple, fast method for the determination of uranium in uranium metal, uranium oxides, and uranyl nitrate solutions has been adapted from the Davies-Gray volumetric method to meet the needs of Y-12. One-gram duplicate aliquots of uranium metal or uranium oxide are dissolved in 1:1 HNO 3 and concentrated H 2 SO 4 to sulfur trioxide fumes, and then diluted to 100-mL volume. Duplicate aliquots are then weighed for analysis. For uranyl nitrate samples, duplicate aliquots containing between 50 and 150 mg of U are weighed and analyzed directly. The weighed aliquot is transferred to a Berzelius beaker; 1.5 M sulfamic acid is added, followed in order by concentrated phosphoric acid, 1 M ferrous sulfate, and (after a 30-second interval) the oxidizing reagent. After a timed 3-minute waiting period, 100 mL of the 0.1% vanadyl sulfate-sulfuric acid mixture is added. The sample is then titrated past its endpoint with standard potassium dichromate, and the endpoint is determined by second derivative techniques on a mV/weight basis
International Nuclear Information System (INIS)
Thompson, A.J.; Lehrenbaum, W.U.; Lashway, D.C.
2002-01-01
The US domestic uranium industry is at a crossroads. Historic low prices for uranium, combined with stringent and often irrational regulatory requirements, pose a very real threat to the industry's continued viability. The Nuclear Regulatory Commission has taken a number of innovative steps to reform and rationalize its regulatory programme. However, if the domestic uranium recovery industry is to remain viable, additional steps toward innovation and reform are needed, and effective implementation of reforms adopted by the Commission is essential. (author)
Improving gross count gamma-ray logging in uranium mining with the NGRS probe
Directory of Open Access Journals (Sweden)
Carasco C.
2018-01-01
Full Text Available AREVA Mines and the Nuclear Measurement Laboratory of CEA Cadarache are collaborating to improve the sensitivity and precision of uranium concentration measurement by means of gamma ray logging. The determination of uranium concentration in boreholes is performed with the Natural Gamma Ray Sonde (NGRS based on a NaI(Tl scintillation detector. The total gamma count rate is converted into uranium concentration using a calibration coefficient measured in concrete blocks with known uranium concentration in the AREVA Mines calibration facility located in Bessines, France. Until now, to take into account gamma attenuation in a variety of boreholes diameters, tubing materials, diameters and thicknesses, filling fluid densities and compositions, a semi-empirical formula was used to correct the calibration coefficient measured in Bessines facility. In this work, we propose to use Monte Carlo simulations to improve gamma attenuation corrections. To this purpose, the NGRS probe and the calibration measurements in the standard concrete blocks have been modeled with MCNP computer code. The calibration coefficient determined by simulation, 5.3 s-1.ppmU-1 ± 10%, is in good agreement with the one measured in Bessines, 5.2 s-1.ppmU-1. Based on the validated MCNP model, several parametric studies have been performed. For instance, the rock density and chemical composition proved to have a limited impact on the calibration coefficient. However, gamma self-absorption in uranium leads to a nonlinear relationship between count rate and uranium concentration beyond approximately 1% of uranium weight fraction, the underestimation of the uranium content reaching more than a factor 2.5 for a 50 % uranium weight fraction. Next steps will concern parametric studies with different tubing materials, diameters and thicknesses, as well as different borehole filling fluids representative of real measurement conditions.
Improving gross count gamma-ray logging in uranium mining with the NGRS probe
Carasco, C.; Pérot, B.; Ma, J.-L.; Toubon, H.; Dubille-Auchère, A.
2018-01-01
AREVA Mines and the Nuclear Measurement Laboratory of CEA Cadarache are collaborating to improve the sensitivity and precision of uranium concentration measurement by means of gamma ray logging. The determination of uranium concentration in boreholes is performed with the Natural Gamma Ray Sonde (NGRS) based on a NaI(Tl) scintillation detector. The total gamma count rate is converted into uranium concentration using a calibration coefficient measured in concrete blocks with known uranium concentration in the AREVA Mines calibration facility located in Bessines, France. Until now, to take into account gamma attenuation in a variety of boreholes diameters, tubing materials, diameters and thicknesses, filling fluid densities and compositions, a semi-empirical formula was used to correct the calibration coefficient measured in Bessines facility. In this work, we propose to use Monte Carlo simulations to improve gamma attenuation corrections. To this purpose, the NGRS probe and the calibration measurements in the standard concrete blocks have been modeled with MCNP computer code. The calibration coefficient determined by simulation, 5.3 s-1.ppmU-1 ± 10%, is in good agreement with the one measured in Bessines, 5.2 s-1.ppmU-1. Based on the validated MCNP model, several parametric studies have been performed. For instance, the rock density and chemical composition proved to have a limited impact on the calibration coefficient. However, gamma self-absorption in uranium leads to a nonlinear relationship between count rate and uranium concentration beyond approximately 1% of uranium weight fraction, the underestimation of the uranium content reaching more than a factor 2.5 for a 50 % uranium weight fraction. Next steps will concern parametric studies with different tubing materials, diameters and thicknesses, as well as different borehole filling fluids representative of real measurement conditions.
Uranium: one utility's outlook
International Nuclear Information System (INIS)
Gass, C.B.
1983-01-01
The perspective of the Arizona Public Service Company (APS) on the uncertainty of uranium as a fuel supply is discussed. After summarizing the history of nuclear power and the uranium industries, a projection is made for the future uranium market. An uncrtain uranium market is attributed to various determining factors that include international politics, production costs, non-commercial government regulation, production-company stability, and questionable levels of uranium sales. APS offers its solutions regarding type of contract, choice of uranium producers, pricing mechanisms, and aids to the industry as a whole. 5 references, 10 figures, 1 table
International Nuclear Information System (INIS)
Fisk, B.
1978-01-01
The subject is covered in sections, entitled: Australia's resources; Northern Territory uranium in perspective; the government's decision [on August 25, 1977, that there should be further development of uranium under strictly controlled conditions]; Government legislation; outlook [for the Australian uranium mining industry]. (U.K.)
Energy Technology Data Exchange (ETDEWEB)
Molinari, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires
1960-12-15
The mechanism and the optimum conditions for preparing uranium mononitride have been studied. The results have been used for hot pressing (250 kg/cm{sup 2}, 1000 deg. C, under vacuum) a mixture of powders of uranium and uranium higher nitrides. The products obtained have been identified by X-ray measurements and may be - at will and depending upon the stoichiometry - either UN, or a cermet a U{sub {alpha}}-UN. As revealed by the curved shape of grain boundaries, the sinters obtained here do not easily evolve towards physico-chemical equilibrium when submitted to heat treatment. This behaviour is quite different from the one observed with uranium monocarbide prepared by a similar method. This fact may be ascribed to the insolubility in the matrix UN of particles of UO{sub 2} being present as impurities. The density, hardness and thermal conductivity of these products are higher than those measured on uranium nitride or cermets U-UN obtained by other methods. (author) [French] Apres une etude prealable du mecanisme et des conditions optimales de nitruration de l'uranium, on a montre qu'il est possible de preparer par frittage sous charge (250 kg/cm{sup 2}, 1000 deg. C sous vide) d'un melange de poudres d'uranium et de nitrures superieurs d'uranium, un produit qui a ete identifie par diffraction de rayons X. On peut ainsi obtenir a volonte, soit le monocarbure UN, soit un cermet U{sub {alpha}}-UN dans le cas de compositions sous-stoechiometriques. Au contraire du monocarbure d'uranium prepare dans des conditions analogues, les produits obtenus ici, soumis a un traitement thermique, n'evoluent pas facilement vers un etat d'equilibre physico-chimique caracterise par l'existence de joints de grains rectilignes. On attribue ce phenomene a l'insolubilite de l'impurete UO{sub 2} dans UN. La densite, la durete, la conductibilite thermique de ces produits se revelent superieures a celles des nitrures d'uranium ou des cermets U-UN obtenus par les autres methodes. (auteur)
Energy Technology Data Exchange (ETDEWEB)
Francis, C. W.
1993-09-01
To address the management of uranium-contaminated soils at Fernald and other DOE sites, the DOE Office of Technology Development formed the Uranium in Soils Integrated Demonstration (USID) program. The USID has five major tasks. These include the development and demonstration of technologies that are able to (1) characterize the uranium in soil, (2) decontaminate or remove uranium from the soil, (3) treat the soil and dispose of any waste, (4) establish performance assessments, and (5) meet necessary state and federal regulations. This report deals with soil decontamination or removal of uranium from contaminated soils. The report was compiled by the USID task group that addresses soil decontamination; includes data from projects under the management of four DOE facilities [Argonne National Laboratory (ANL), Los Alamos National Laboratory (LANL), Oak Ridge National Laboratory (ORNL), and the Savannah River Plant (SRP)]; and consists of four separate reports written by staff at these facilities. The fundamental goal of the soil decontamination task group has been the selective extraction/leaching or removal of uranium from soil faster, cheaper, and safer than current conventional technologies. The objective is to selectively remove uranium from soil without seriously degrading the soil`s physicochemical characteristics or generating waste forms that are difficult to manage and/or dispose of. Emphasis in research was placed more strongly on chemical extraction techniques than physical extraction techniques.
Sandstone-type uranium deposits
International Nuclear Information System (INIS)
Austin, S.R.; D'Andrea, R.F. Jr.
1978-01-01
Three overall factors are necessary for formation of uranium deposits in sandstone: a source of uranium, host rocks capable of transmitting uranium-bearing solutions, and a precipitant. Possible sources of uranium in sandstone-type deposits include groundwaters emanating from granitic highlands, arkosic sediments, tuffaceous material within or overlying the host rocks, connate fluids, and overlying black shales. The first three sources are considered the most likely. Host rocks are generally immature sandstones deposited in alluvial-fan, intermontane-basin or marginal-marine environments, but uranium deposits do occur in well-winnowed barrier-bar or eolian sands. Host rocks for uranium deposits generally show coefficients of permeability on the order of 1 to 100 gal/day/ft 2 . Precipitants are normally agents capable of reducing uranium from the uranyl to the uranous state. The association of uranium with organic matter is unequivocal; H 2 S, a powerful reductant, may have been present at the time of formation of some deposits but may go unnoticed today. Vanadium can serve to preserve the tabular characteristics of some deposits in the near-surface environment, but is considered an unlikely primary precipitant for uranium. Uranium deposits in sandstone are divided into two overall types: peneconcordant deposits, which occur in locally reducing environments in otherwise oxidized sandstones; and roll-type deposits, which occur at the margin of an area where an oxidized groundwater has permeated an otherwise reduced sandstone. Uranium deposits are further broken down into four subclasses; these are described
URANIUM LEACHING AND RECOVERY PROCESS
McClaine, L.A.
1959-08-18
A process is described for recovering uranium from carbonate leach solutions by precipitating uranium as a mixed oxidation state compound. Uranium is recovered by adding a quadrivalent uranium carbon;te solution to the carbonate solution, adjusting the pH to 13 or greater, and precipitating the uranium as a filterable mixed oxidation state compound. In the event vanadium occurs with the uranium, the vanadium is unaffected by the uranium precipitation step and remains in the carbonate solution. The uranium-free solution is electrolyzed in the cathode compartment of a mercury cathode diaphragm cell to reduce and precipitate the vanadium.
International Nuclear Information System (INIS)
Sigurdson, B.E.; Bilokury, M.R.; Snider, R.C.
2002-01-01
Institutional control of a mine site is required to ensure long-term public safety and environmental protection once responsibility for a decommissioned uranium mine site reverts back to the Crown. During the exploration, development, operation and decommissioning phases of a uranium mine's life cycle, public safety and environmental protection are ensured through the Federal and Provincial Environmental Assessment Review process, regulatory permitting and compliance monitoring by the province. However, at present, there is no clear provincial policy with respect to a proponent's application for release from a reclaimed and decommissioned site, and the resulting provincial responsibility for the long-term management and maintenance of the site once a release has been granted. Another policy issue has been identified with respect to the long-term institutional control of previously abandoned uranium mine sites. A number of issues are being considered by the Government of Saskatchewan in developing a policy which addresses the needs of the people of Saskatchewan and which is consistent with the intent of the commitments made by Canada through its ratification of the International Atomic Energy Agency's (IAEA) Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management. (author)
International Nuclear Information System (INIS)
Anon.
1982-01-01
Uranium is the most political of all the elements, the material for the production of both the large amounts of electricity and the most destructive weapons in the world. The problems that its dual potential creates are only now beginning to become evident. Author Norman Moss looks at this situation and sheds light on many of the questions that emerge. The nuclear issue always comes back to how much uranium there is, what can be done with it, and which countries have it. Starting with a concise history of uranium and explaining its technology in terms the nonspecialist can understand, The Politics of Uranium considers the political issues that technical arguments obscure. It tells the little-known story of the international uranium cartel, explains the entanglements of governments with the uranium trade, and describes the consequences of wrong decisions and blunders-especially the problems of nuclear waste. It also examines the intellectual and emotional roots of the anti-nuclear movement
International Nuclear Information System (INIS)
Smith, S.D.
1979-01-01
The calorimeter subgroup of the 1977 ISABELLE Summer Workshop strongly recommended investigation of the uranium-scintillator device because of its several attractive features: (1) increased resolution for hadronic energy, (2) fast time response, (3) high density (i.e., 16 cm of calorimeter per interaction length), and, in comparison with uranium--liquid argon detectors, (4) ease of construction, (5) simple electronics, and (6) lower cost. The AFM group at the CERN ISR became interested in such a calorimeter for substantially the same reasons, and in the fall of 1977 carried out tests on a uranium-scintillator (U-Sc) calorimeter with the same uranium plates used in their 1974 studies of the uranium--liquid argon (U-LA) calorimeter. The chief disadvantage of the scintillator test was that the uranium plates were too small to fully contain the hadronic showers. However, since the scintillator and liquid argon tests were made with the plates, direct comparison of the two types of devices could be made
Method of preparing uranium nitride or uranium carbonitride bodies
International Nuclear Information System (INIS)
Wilhelm, H.A.; McClusky, J.K.
1976-01-01
Sintered uranium nitride or uranium carbonitride bodies having a controlled final carbon-to-uranium ratio are prepared, in an essentially continuous process, from U 3 O 8 and carbon by varying the weight ratio of carbon to U 3 O 8 in the feed mixture, which is compressed into a green body and sintered in a continuous heating process under various controlled atmospheric conditions to prepare the sintered bodies. 6 claims, no drawings
International Nuclear Information System (INIS)
Nelson, R.A.; Chernoff, A.R.; Mager, D.; Goldammer, W.
1993-01-01
The former Soviet Union demands for uranium feed materials were primarily met by the East German Republic. A small area 200 km long and 50 km wide in the provinces of Saxony and Thuringia provided more than half of the uranium concentrate processed by the Soviet Union, and used for nuclear weapons development and power generation. With the majority of the ore processed in Germany of an average lower grade than a number of deposits found around the world, the mining and milling resulted in an enormous scale of surface disturbance and quantities of mill tailings concentrated in a relatively small densely populated geographical area. As a result of the re-unification of the two Germanies, all uranium extraction and processing activities were suddenly brought to a halt for economic reasons. The former soviet-East German corporation responsible for the uranium concentrate production was changed into a German state-operated company tasked with the facility decommissioning and environmental restoration. Code-named WISMUT (the German word for Bismuth) during the cold war, this organization was literally changed overnight from a self-sufficient, autonomously operating and state controlled effort into a public works, environmentally conscious corporation
International Nuclear Information System (INIS)
Perkin, D.J.
1982-01-01
Developments in the Australian uranium industry during 1980 are reviewed. Mine production increased markedly to 1841 t U 3 O 8 because of output from the new concentrator at Nabarlek and 1131 t of U 3 O 8 were exported at a nominal value of $37.19/lb. Several new contracts were signed for the sale of yellowcake from Ranger and Nabarlek Mines. Other developments include the decision by the joint venturers in the Olympic Dam Project to sink an exploration shaft and the release of an environmental impact statement for the Honeymoon deposit. Uranium exploration expenditure increased in 1980 and additions were made to Australia's demonstrated economic uranium resources. A world review is included
International Nuclear Information System (INIS)
Levin, M.
1980-04-01
An extensive geological, hydrological and hydrochemical study was conducted to determine the uranium potential of an area which includes the greater part of the Gordonia District and part of the bordering Kuruman District. The area is situated between 21 and 22 degrees east, the Kuruman River in the north and the Orange River in the south. All berohole information germane to the area, such as Government and private drill records have been studied. As a result of this study maps of the area have been compiled, showing surface and pre-Karoo geology, the pre-Karoo and pre-Kalahari topography and the thickness of the Karoo and post-Karoo cover. Contour maps of water levels were compiled from which a regional east-west flow pattern was deduced, indicating a large groundwater basin which could be divided into four smaller basins. Hydrochemical studies substantiate the inferred flow pattern of the groundwater. Of prime importance in this investigation was the study of the distribution of uranium in the groundwater of the area and its association with the various lithologies encountered. Radiometric borehole logging of all accessible boreholes in the most promising areas delineated by this study confirmed the presence of uranium mineralisation in the depositional basins (in particular the Dwyka Tillite Formation) west of the granite-gneiss ridge. Uranium mineralisation in surficial deposits was also discovered as a result of the reassessment of radiometric airborne data obtained previously. It is concluded that potential economic uranium deposits may exist in the Dwyka Tillite Formation northwest of Upington and in the surficial diatomaceous earth deposits on the farm Rus-en-Vrede [af
International Nuclear Information System (INIS)
Crull, A.W.
1978-01-01
All energy sources and technologies, including uranium and the nuclear industry, are needed to provide power. Public misunderstanding of the nature of uranium and how it works as a fuel may jeopardize nuclear energy as a major option. Basic chemical facts about uranium ore and uranium fuel technology are presented. Some of the major policy decisions that must be made include the enrichment, stockpiling, and pricing of uranium. Investigations and lawsuits pertaining to uranium markets are reviewed, and the point is made that oil companies will probably have to divest their non-oil energy activities. Recommendations for nuclear policies that have been made by the General Accounting Office are discussed briefly
International Nuclear Information System (INIS)
Gradoz, Philippe
1993-01-01
After having reported a bibliographical study on penta-methylcyclopentadienyl uranium complexes, and a description of the synthesis and radioactivity of uranium (III) and (IV) boron hydrides compounds, this research thesis reports the study of mono and bis-tetramethyl-phospholyl uranium complexes comprising chloride, boron hydride, alkyl and alkoxide ligands. The third part reports the comparison of structures, stabilities and reactions of homologue complexes in penta-methylcyclopentadienyl and tetramethyl-phospholyl series. The last part addresses the synthesis of tris-phospholyl uranium (III) and (IV) complexes. [fr
International Nuclear Information System (INIS)
Silva Neto, Joao Batista da
2008-01-01
It is a well known fact that the use of uranium tetrafluoride allows flexibility in the production of uranium suicide and uranium oxide fuel. To its obtention there are two conventional routes, the one which reduces uranium from the UF 6 hydrolysis solution with stannous chloride, and the hydro fluorination of a solid uranium dioxide. In this work we are introducing a third and a dry way route, mainly utilized to the recovery of uranium from the liquid effluents generated in the uranium hexafluoride reconversion process, at IPEN/CNEN-SP. Working in the liquid phase, this route comprises the recuperation of ammonium fluoride by NH 4 HF 2 precipitation. Working with the solid residues, the crystallized bifluoride is added to the solid UO 2 , which comes from the U mini plates recovery, also to its conversion in a solid state reaction, to obtain UF 4 . That returns to the process of metallic uranium production unity to the U 3 Si 2 obtention. This fuel is considered in IPEN CNEN/SP as the high density fuel phase for IEA-R1m reactor, which will replace the former low density U 3 Si 2 -Al fuel. (author)
Willit, James L [Batavia, IL; Ackerman, John P [Prescott, AZ; Williamson, Mark A [Naperville, IL
2009-12-29
This is a single stage process for treating spent nuclear fuel from light water reactors. The spent nuclear fuel, uranium oxide, UO.sub.2, is added to a solution of UCl.sub.4 dissolved in molten LiCl. A carbon anode and a metallic cathode is positioned in the molten salt bath. A power source is connected to the electrodes and a voltage greater than or equal to 1.3 volts is applied to the bath. At the anode, the carbon is oxidized to form carbon dioxide and uranium chloride. At the cathode, uranium is electroplated. The uranium chloride at the cathode reacts with more uranium oxide to continue the reaction. The process may also be used with other transuranic oxides and rare earth metal oxides.
International Nuclear Information System (INIS)
1981-01-01
The objective of this investigation is to examine what is generally known about uranium resources, what is subject to conjecture, how well do the explorers themselves understand the occurrence of uranium, and who are the various participants in the exploration process. From this we hope to reach a better understanding of the quality of uranium resource estimates as well as the nature of the exploration process. The underlying questions will remain unanswered. But given an inability to estimate precisely our uranium resources, how much do we really need to know. To answer this latter question, the various Department of Energy needs for uranium resource estimates are examined. This allows consideration of whether or not given the absence of more complete long-term supply data and the associated problems of uranium deliverability for the electric utility industry, we are now threatened with nuclear power plants eventually standing idle due to an unanticipated lack of fuel for their reactors. Obviously this is of some consequence to the government and energy consuming public. The report is organized into four parts. Section I evaluates the uranium resource data base and the various methodologies of resource assessment. Part II describes the manner in which a private company goes about exploring for uranium and the nature of its internal need for resource information. Part III examines the structure of the industry for the purpose of determining the character of the industry with respect to resource development. Part IV arrives at conclusions about the emerging pattern of industrial behavior with respect to uranium supply and the implications this has for coping with national energy issues
Uranium processing and properties
2013-01-01
Covers a broad spectrum of topics and applications that deal with uranium processing and the properties of uranium Offers extensive coverage of both new and established practices for dealing with uranium supplies in nuclear engineering Promotes the documentation of the state-of-the-art processing techniques utilized for uranium and other specialty metals
Radon assessment in thermal waters in Imbabura and Pichincha provinces
International Nuclear Information System (INIS)
Aragon, Mayra
2001-01-01
The radon is a radioactive, odorless and colorless gas, that generated in the terrestrial crust by the radioactive decay of the radio, originating of the chain of disintegration of the Uranium-238, can migrate considerable distances during its short time of life (3.82 days), from the ground to the water and later to the atmosphere. For the accomplishment of the preliminary study of quantification of radon in thermal sources, it was come to the sampling from radon-222 in bath waters different from the provinces of Pichincha and Imbabura. For which a particle accountant was used alpha, that uses the method of flashing, emitted by ionizing particles at the moment at which the radium decays in its descendant radon, and this one in its next descendants. The water samples are analyzed in the Pylon model RM-1003, particle accountant alpha, that uses for the harvesting of the gas, cameras that contain sensible detectors activated zinc sulfide cells with silver. For this sampling it was taken into account qualitative factors like: rain temperature, presence, origin of the source, proximity of some hill or volcano, presence of seismic movements, among others. These parameters could affect to the measurements of concentration of radon. Of the obtained results, we can conclude that of the 13 bath, those of the province of Pichincha, specially three of them (Tesalia, Sillunchi, Cunuyacu), contain greater concentration of radon that those of the province of Imbabura. In addition in general for all the selected bath it was verified that the concentration of radon is greater for the source than for the swimming pool. Finally it is possible to be emphasized values of concentration of radon that are around 1000-15000 Bq/m3 for the source, and the swimming pool of 100-800 Bq/m3. (The author)
International Nuclear Information System (INIS)
Erkes, P.
1981-06-01
Uranium supply and demand as projected by the Uranium Institute is discussed. It is concluded that for the industrialized countries, maximum energy independence is a necessity. Hence it is necessary to achieve assurance of supply for uranium used in thermal power reactors in current programs and eventually to move towards breeders
Uranium-236 as an indicator of fuel-cycle uranium in ground water
International Nuclear Information System (INIS)
Jaquish, R.E.
1989-08-01
Environmental monitoring on and around the Hanford Site includes regular sampling of onsite monitoring wells and offsite farm wells. Uranium has been identified in the ground water onsite and also in water from farm wells located on the east side of the Columbia River, across from the Hanford Site. Information on the hydrology of the area indicates that the source of the offsite uranium is not the Hanford Site. This study evaluated the isotopic composition of the uranium in water from the various wells to differentiate the onsite uranium contamination from natural uranium offsite. 5 refs., 2 figs., 2 tabs
Uranium isotopes determination in urine samples using alpha spectrometry and ICP-MS
Energy Technology Data Exchange (ETDEWEB)
Rosa, Mychelle M.L.; Maihara, Vera A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Tine, Fernanda D.; Santos, Sandra M.C.; Bonifacio, Rodrigo L.; Taddei, Maria HelenaT. [Comissao Nacional de Energia Nuclear (LAPOC/CNEN-MG), Pocos de Caldas, MG (Brazil). Laboratorio de Pocos de Caldas
2015-07-01
The action of determining the concentration of uranium isotopes in biological samples, 'in vitro' bioassay, is an indirect method for evaluating the incorporation and quantification of these radionuclides internally deposited. When incorporated, these radionuclides tend to be disposed through excretion, with urine being the main source of data because it can be easily collected and analyzed. The most widely used methods for determination of uranium isotopes ({sup 234}U, {sup 235}U and {sup 238}U) are Alpha Spectrometry and ICP-MS. This work presents a comparative study for the determination of uranium isotopes using these two methodologies in real samples from occupationally exposed workers. In order to validate the methodology, a sample of the intercomparison exercise organized by PROCORAD (Association pour la Promotion du Controle de Qualite des Analyses de Biologie Medicale em Radiotoxicologie) was used, and the results were statistically compared applying the Student's t-test. (author)
International Nuclear Information System (INIS)
1989-01-01
In 1988 Canada's five uranium producers reported output of concentrate containing a record 12,470 metric tons of uranium (tU), or about one third of total Western world production. Shipments exceeded 13,200 tU, valued at $Cdn 1.1 billion. Most of Canada's uranium output is available for export for peaceful purposes, as domestic requirements represent about 15 percent of production. The six uranium marketers signed new sales contracts for over 11,000 tU, mostly destined for the United States. Annual exports peaked in 1987 at 12,790 tU, falling back to 10,430 tU in 1988. Forward domestic and export contract commitments were more than 70,000 tU and 60,000 tU, respectively, as of early 1989. The uranium industry in Canada was restructured and consolidated by merger and acquisition, including the formation of Cameco. Three uranium projects were also advanced. The Athabasca Basin is the primary target for the discovery of high-grade low-cost uranium deposits. Discovery of new reserves in 1987 and 1988 did not fully replace the record output over the two-year period. The estimate of overall resources as of January 1989 was down by 4 percent from January 1987 to a total (measured, indicated and inferred) of 544,000 tU. Exploration expenditures reached $Cdn 37 million in 1987 and $59 million in 1988, due largely to the test mining programs at the Cigar Lake and Midwest projects in Saskatchewan. Spot market prices fell to all-time lows from 1987 to mid-1989, and there is little sign of relief. Canadian uranium production capability could fall below 12,000 tU before the late 1990s; however, should market conditions warrant output could be increased beyond 15,000 tU. Canada's known uranium resources are more than sufficient to meet the 30-year fuel requirements of those reactors in Canada that are now or are expected to be in service by the late 1990s. There is significant potential for discovering additional uranium resources. Canada's uranium production is equivalent, in
Chemical thermodynamics of uranium
International Nuclear Information System (INIS)
Grenthe, I.; Fuger, J.; Lemire, R.J.; Muller, A.B.; Nguyen-Trung Cregu, C.; Wanner, H.
1992-01-01
A comprehensive overview on the chemical thermodynamics of those elements that are of particular importance in the safety assessment of radioactive waste disposal systems is provided. This is the first volume in a series of critical reviews to be published on this subject. The book provides an extensive compilation of chemical thermodynamic data for uranium. A description of procedures for activity corrections and uncertainty estimates is given. A critical discussion of data needed for nuclear waste management assessments, including areas where significant gaps of knowledge exist is presented. A detailed inventory of chemical thermodynamic data for inorganic compounds and complexes of uranium is listed. Data and their uncertainty limits are recommended for 74 aqueous complexes and 199 solid and 31 gaseous compounds containing uranium, and on 52 aqueous and 17 solid auxiliary species containing no uranium. The data are internally consistent and compatible with the CODATA Key Values. The book contains a detailed discussion of procedures used for activity factor corrections in aqueous solution, as well as including methods for making uncertainty estimates. The recommended data have been prepared for use in environmental geochemistry. Containing contributions written by experts the chapters cover various subject areas such a s: oxide and hydroxide compounds and complexes, the uranium nitrides, the solid uranium nitrates and the arsenic-containing uranium compounds, uranates, procedures for consistent estimation of entropies, gaseous and solid uranium halides, gaseous uranium oxides, solid phosphorous-containing uranium compounds, alkali metal uranates, uncertainties, standards and conventions, aqueous complexes, uranium minerals dealing with solubility products and ionic strength corrections. The book is intended for nuclear research establishments and consulting firms dealing with uranium mining and nuclear waste disposal, as well as academic and research institutes
Radiological environmental monitoring around the mining sites in Argentina
International Nuclear Information System (INIS)
Quintana, Eduardo E.; Gomez, Juan C.; Palacios, Miguel A.
2004-01-01
The uranium mining industry began its development in Argentina in the fifties. Since then, several installations have operated as uranium underground mining until late seventies, when that mines were closed. Since then, open pit exploitation has been used. Milling facilities were installed in the mining areas or close to them. The environmental radiological surveillance and the impact assessment presented in this work are referred to the uranium ore mining and milling plants Tonco, in Salta province; Pichinan, in Chubut province; San Rafael and Malargue, in Mendoza province; Los Gigantes, in Cordoba province; La Estela, in San Luis province and Los Colorados in La Rioja province. The environmental radiological surveillance programme results carried out from the beginning of the operations are presented and include uranium and radium concentrations in surface waters and sediments. The results obtained in waters upstream and downstream the uranium mining complexes are compared and no significant differences were observed. Moreover, taking into consideration the critical exposition pathways of the population living in the area, no significant levels of exposition were observed. (author)
International Nuclear Information System (INIS)
Choudhary, Sangeeta; Sar, Pinaki
2011-01-01
A multimetal resistant Pseudomonas strain isolated from a uranium mine waste site of Jaduguda, India, was characterized for its potential application in bioremediation. Nearly complete 16 Sr RNA gene sequence and fatty acid methyl ester analyses confirmed the identity of this bacterium as Pseudomonas aeruginosa. This bacterium exhibited high U-resistance i.e. up to an exposure of 6 h in 100 mg UL -1 solution (pH 4.0) and accumulation (maximum of 275 mg Ug -1 cell dry wt.) properties. Microcosm studies further proved the ability of the strain to remove soluble uranium (99%) from U-mine effluent and sequester it as U oxide and phosphate minerals while maintaining its viability. Considering the survival of this strain in U-mine site co-contaminated with other heavy metals, genetic basis of metal resistance was investigated. The bacterium was resistant to 3, 2 or 6 mM of Cu, Cd, or Zn, respectively. Polymerase chain reaction based detection followed by sequence identity and phylogenetic analysis revealed presence of specific metal resistance genes copA (copper resistance determinant) and czcA (RND type heavy metal efflux) in this isolate. Real-time PCR expression studies of these genes indicated significantly increased expression of both the genes in response to Cu, Cd, or Zn. Maximum up regulation of copA and czcA genes was observed following exposure (30 mm) to 25 μm of Cu or 10 μm Cd respectively. High levels of mRNA transcripts of copA and czcA genes in response to specific metals suggest that these resistance systems have important role in conferring metal resistance to the bacterium. Response of sodA an antioxidant Mn-cofactored superoxide dismutase gene to metal stress revealed that induction of this stress gene was not evident at lower concentration(s) of metals, the concentration(s) that cause maximum up- regulation of metal resistance genes. Higher test metal concentration or extended period of exposure, however, resulted in expression of sodA gene. The
Precipitation of uranium peroxide from the leach liquor of uranium ores
International Nuclear Information System (INIS)
Gao Xizhen; Lin Sirong; Guo Erhua; Lu Shijie
1995-06-01
A chemical precipitation process of recovering uranium from the leach liquor of uranium ores was investigated. The process primarily includes the precipitation of iron with lime, the preprocessing of the slurry of iron hydroxides and the precipitation of uranium with H 2 O 2 . The leach liquor is neutralized by lime milk to pH 3.7 to precipitate the iron hydroxides which after flocculation and settle is separated out and preprocessed at 170 degree C in an autoclave. H 2 O 2 is then used to precipitate uranium in the leach liquor free of iron, and the pH of process for uranium precipitation adjusted by adding MgO slurry to 3.5. The barren solution can be used to wash the filter cakes of leach tailing. The precipitated slurry of iron hydroxides after being preprocessed is recycled to leaching processes for recovering uranium in it. This treatment can not only avoid the filtering of the slurry of iron hydroxides, but also prevent the iron precipitate from redissolving and consequently the increase of iron concentration in the leach liquor. The results of the investigation indicate that lime, H 2 O 2 and MgO are the main chemical reagents used to obtain the uranium peroxide product containing over 65% uranium from the leach liquor, and they also do not cause environmental pollution. In accordance with the uranium content in the liquor, the consumption of chemical reagent for H 2 O 2 (30%) and MgO are 0.95 kg/kgU and 0.169 kg/kgU, respectively. (1 fig., 8 tabs., 7 refs.)
Uranium in Soils Integrated Demonstration: Technology summary, March 1994
International Nuclear Information System (INIS)
1994-03-01
A recent Pacific Northwest Laboratory (PNL) study identified 59 waste sites at 14 DOE facilities across the nation that exhibit radionuclide contamination in excess of established limits. The rapid and efficient characterization of these sites, and the potentially contaminated regions that surround them represents a technological challenge with no existing solution. In particular, the past operations of uranium production and support facilities at several DOE sites have occasionally resulted in the local contamination of surface and subsurface soils. Such contamination commonly occurs within waste burial sites, cribs, pond bottom sediments and soils surrounding waste tanks or uranium scrap, ore, tailings, and slag heaps. The objective of the Uranium In Soils Integrated Demonstration is to develop optimal remediation methods for soils contaminated with radionuclides, principally uranium (U), at DOE sites. It is examining all phases involved in an actual cleanup, including all regulatory and permitting requirements, to expedite selection and implementation of the best technologies that show immediate and long-term effectiveness specific to the Fernald Environmental Management Project (FEMP) and applicable to other radionuclide contaminated DOE sites. The demonstration provides for technical performance evaluations and comparisons of different developmental technologies at FEMP sites, based on cost-effectiveness, risk-reduction effectiveness, technology effectiveness, and regulatory and public acceptability. Technology groups being evaluated include physical and chemical contaminant separations, in situ remediation, real-time characterization and monitoring, precise excavation, site restoration, secondary waste treatment, and soil waste stabilization
Uranium material removing and recovering device
International Nuclear Information System (INIS)
Takita, Shin-ichi.
1997-01-01
A uranium material removing and recovering device for use in removing surplus uranium heavy metal (UO 2 ) generated in a uranium handling facility comprises a uranium material removing device and a uranium material recovering device. The uranium material removing device comprises an adsorbing portion filled with a uranium adsorbent, a control portion for controlling the uranium adsorbent of the uranium adsorbing portion by a controlling agent, a uranium adsorbing device connected thereto and a jetting device for jetting the adsorbing liquid to equipments deposited with uranium. The recovering device comprises a recovering apparatus for recovering uranium materials deposited with the adsorbent liquid removed by the jetting device and a recovering tank for storing the recovered uranium materials. The device of the present invention can remove surplus uranium simply and safely, mitigate body's load upon removing and recovering operations, facilitate the processing for the exchange of the adsorbent and reduces the radioactive wastes. (T.M.)
International Nuclear Information System (INIS)
Xue Wei; Xue Chunji; Chi Guoxiang
2012-01-01
The Ordos Basin is not only an important uranium mineralization province but also a major producer of oil. gas and coal in China. The genetic relationship between uranium mineralization and hydrocarbons has been recognized by a number of previous studies, but it has not been well understood in terms of hydrodynamics of basin fluid flow. In a previous study we have demonstrated that the preferential localization of uranium mineralization in the upper part of the Jurassic strata may have been related to the interface of an upward flowing, reducing fluid and a downward flowing, oxidizing fluid, and that this interface may have been controlled by the interplay between fluid overpressure, which was related to disequilibrium sediment compaction and drove the upward flow, and topographic relief which drove the down- ward flow. In the present study, we carried out numerical modeling for the contribution of oil and gas generation to the development of fluid overpressure, in addition to sediment compaction and heating. Our results indicate that when hydrocarbon generation was taken into account, fluid overpressure during the Cretaceous was more than doubled in comparison with the simulation when hydrocarbon generation was not considered. Furthermore, fluid overpressure dissipation after ceasing of sedimentation slowed down relative to the no-hydrocarbon generation case. These results suggest that hydrocarbon generation may have played an important role in uranium mineralization, not only in providing reducing agents required for the mineralization, but also in contributing to the driving force to maintain the upward flow against the pushing of topography driven. downward flow, thus helping stabilize the interface between the two fluid system and localization of uranium mineralization. (authors)
Recovering uranium from phosphates
Energy Technology Data Exchange (ETDEWEB)
Bergeret, M [Compagnie de Produits Chimiques et Electrometallurgiques Pechiney-Ugine Kuhlmann, 75 - Paris (France)
1981-06-01
Processes for the recovery of the uranium contained in phosphates have today become competitive with traditional methods of working uranium sources. These new possibilities will make it possible to meet more rapidly any increases in the demand for uranium: it takes ten years to start working a new uranium deposit, but only two years to build a recovery plant.
International Nuclear Information System (INIS)
Wei Keqin; Lin Ruifen; Wang Zhixiang
1988-01-01
A comprehensive environmental isotope investigation of several complex groundwater systems and the mixing of groundwater with surface water in the region of Taiyuan, Shanxi Province of China, is presented. Environmental isotopes, including stable isotopes, tritium and uranium series in water and its activity ratio 234 U/ 238 U are applied to divide karstic groundwaters into separate Xishan and Dongshan systems. The Xishan karstic water system shows a great scattering of isotope data. This results from the mixing of karstic groundwater and surface water from the Fenhe River. The Dongshan system is homogeneous and karstic water is tritium free and its age should be more than 50-100 a. The increase in uranium activity ratio, which is correlated with the length of the flow paths, shows the run-off direction of the Dongshan karstic water system towards the major natural outlet, the Lancun Spring. The altitudes of recharge of Xishan and Dongshan karstic waters are evaluated as 1400 m and 1300 m, respectively. The ages of fissure groundwaters in metamorphic rocks are determined in terms of their tritium content. Some practical considerations upon groundwater management are also drawn from isotope results. (author). 9 refs, 10 figs, 9 tabs
Sukegawa, Y; Ohki, K; Suzuki, S; Yoshida, M
2002-01-01
This report is completed about the measurement test and the proofreading of passive gamma - rays measurement method for Non - destructive assay of uranium in a uranium-contaminated waste. The following are the results of the test. 1) The estimation of the amount of uranium by ionization survey meter is difficult for low intensity of gamma-rays emitted from uranium under about 50g. 2) The estimation of the amount of uranium in the waste by NaI detector is possible in case of only uranium, but the estimation from mixed spectrums with transmission source (60-cobalt) is difficult to confirm target peaks. 3) If daughter nuclides of uranium and thorium chain of uranium ore exist, measurement by NaI detector is affected by gamma-rays from the daughter nuclides seriously-As a result, the estimation of the amount of uranium is difficult. 4) The measurement of uranium in a uranium-contaminated waste by germanium detector is possible to estimate of uranium and other nuclides. 5) As to estimation of the amount of uranium...
International Nuclear Information System (INIS)
Anon.
1991-01-01
The Jabiluka uranium and gold deposit located in the Northern Territory of Australia is the world's largest known primary uranium deposits and as such has the potential to become one of the most important uranium projects in the world. Despite the financial and structural challenges facing the major owner Pancontinental Mining Limited and the changing political policies in Australia, Jabiluka is well situated for development during the 1990's. With the availability of numerous financial and development alternatives, Jabiluka could, by the turn of the century, take its rightful place among the first rank of world uranium producers. The paper discusses ownership, location, property rights, licensing, environmental concerns, marketing and development, capital costs, royalties, uranium policy considerations, geologic exploration history, regional and site geology, and mining and milling operations
Uranium and the War: The effects of depleted uranium weapons in Iraq
International Nuclear Information System (INIS)
Jon williams
2007-01-01
The U.S. Army revealed in March 2003 that it dropped between 320 and 390 tons of depleted uranium during the Gulf War-the first time the material was ever used in combat-and it is estimated that more still has been dropped during the current invasion, though there have been no official counts as yet. Nuclear weapons and nuclear power plants require highly radioactive uranium, so the uranium 238 is removed from the naturally occurring uranium by a process known as enrichment. Depleted uranium is the by-product of the uranium enrichment process. Depleted uranium was a major topic of discussion during a Feb. 24 forum at Santa Cruz with speakers from the Iraq Veterans Against War (IVAW). The panel consisted of five members of the IVAW chapter in Olympia, Washington who visited Santa Cruz as part of a speaking tour of the west coast. These members of the IVAW believe that their experiences in the Gulf War were the beginnings of what will be a long-term health problem in the region. A study conducted by the Pentagon in 2002 predicted that every future battlefield will be contaminated with depleted uranium. Up-to-date health information from Iraq is difficult to come by. But a November report from Al-jazeera concluded that the cancer rate in Iraq has increased tenfold, and the number of birth defects has multiplied fivefold times since the 1991 war. The increase is believed to be caused by depleted uranium.
Selective Removal of Uranium from the Washing Solution of Uranium-Contaminated Soil
Energy Technology Data Exchange (ETDEWEB)
Kim, Seung Soo; Han, G. S.; Kim, G. N.; Koo, D. S.; Jeong, J. W.; Choi, J. W. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2015-10-15
This study examined selective removal methods of uranium from the waste solution by ion exchange resins or solvent extraction methods to reduce amount of the 2{sup nd} waste. Alamine-336, known as an excellent extraction reagent of uranium from the leaching solution of uranium ore, did not remove uranium from the acidic washing solution of soil. Uranyl ions in the acidic waste solution were sorbed on ampholyte resin with a high sorption efficiency, and desorbed from the resin by a washing with 0.5 M Na{sub 2}CO{sub 3} solution at 60 .deg. C. However, the uranium dissolved in the sulfuric acid solution was not sorbed onto the strong anion exchanger resins. A great amount of uranium-contaminated (U-contaminated) soil had been generated from the decommissioning of a uranium conversion plant. Our group has developed a decontamination process with washing and electrokinetic methods to decrease the amount of waste to be disposed of. However, this process generates a large amount of waste solution containing various metal ions.
Recovery of uranium from seawater
International Nuclear Information System (INIS)
Hirotsu, Takahiro; Takagi, Norio; Katoh, Shunsaku
1995-01-01
Present status of the development of chelating adsorbents for the recovery of uranium from seawater is outlined with emphasis on the research by the author. Uranium is estimated to exist as stable tri (carbonate) uranylate (6) ion in seawater in a very low concentration. The adsorbent for uranium from seawater in a very low concentration. The adsorbent for uranium from seawater should have high selectivity and affinity for uranium around pH 8. The required characteristics for uranium adsorbent are examined. Various chelating adsorbents have been proposed for the uranium adsorbent and their structures are discussed. Amidoxime type adsorbents have the highest adsorbing power for uranium among the adsorbents hitherto developed and fibrous amidoxime adsorbents are most promising for the practical application. Synthesis, structure and suitable shape of the amidoxime adsorbents are discussed. Uranium adsorption behavior and the amount of saturated adsorption are examined theoretically based on the complexation of an amidoxime monomer and the formula for the adsorption equiliburium is derived. The adsorption and recovery process for uranium from seawater is composed of adsorption, desorption, separation and concentration and finally, uranium is recovered as the yellow cake. A floating body mooring system is proposed by Nobukawa. (T.H.)
Uranium producers foresee new boom
International Nuclear Information System (INIS)
McIntyre, H.
1979-01-01
The status of uranium production in Canada is reviewed. Uranium resources in Saskatchewan and Ontario are described and the role of the Cluff Lake inquiry in securing a government decision in favour of further uranium development is mentioned. There have been other uranium strikes near Kelowna, British Columbia and in the Northwest Territories. Increasing uranium demand and favourable prices are making the development of northern resources economically attractive. In fact, all uranium currently produced has been committed to domestic and export contracts so that there is considerable room for expanding the production of uranium in Canada. (T.I.)
International Nuclear Information System (INIS)
Oh, Won Zin; Jung, Chong Hun; Lee, Kune Woo; Won, Hui Jun; Choi, Wang Kyu; Kim, Gye Nam; Lee, Yu Ri; Lee, Joong Moung
2005-12-01
The up-to-date electrochemical uranium separation technology has been developed for uranium sludge waste treatment funded by a long term national nuclear technology development program. The objective of the studies is to examine applicability of the uranium separation technology to making use of the low grade uranium resources in the country. State of the arts of uranium separation and recovery from the low grade national uranium resources. - The amount of the high grade uranium resources(0.1 % U 3 O 8 contents) in the world is 1,750,000MTU and that of the low grade uranium resources(0.04 % U 3 O 8 contents) in the country is 340,000MTU. - The world uranium price will be increase to more than 30$/l0b in 10 years, so that the low grade uranium in the country become worth while to recover. - The conventional uranium recovery technologies are based on both acidic - The ACF electrochemical uranium separation technology is the state of the art technology in the world and the adsorption capability of 690 mgU/g is several ten times higher than that of a conventional zeolite and the uranium stripping efficiency by desorption is more than 99%. So, this technology is expected to replace the existing solvent extraction technology. Feasibility of the ACF electrochemical uranium separation technology as an uranium recovery method. Lab scale demonstration of uranium separation and recovery technologies have been carried out by using an ACF electrochemical method
METHOD OF RECOVERING URANIUM COMPOUNDS
Poirier, R.H.
1957-10-29
S>The recovery of uranium compounds which have been adsorbed on anion exchange resins is discussed. The uranium and thorium-containing residues from monazite processed by alkali hydroxide are separated from solution, and leached with an alkali metal carbonate solution, whereby the uranium and thorium hydrorides are dissolved. The carbonate solution is then passed over an anion exchange resin causing the uranium to be adsorbed while the thorium remains in solution. The uranium may be recovered by contacting the uranium-holding resin with an aqueous ammonium carbonate solution whereby the uranium values are eluted from the resin and then heating the eluate whereby carbon dioxide and ammonia are given off, the pH value of the solution is lowered, and the uranium is precipitated.
International Nuclear Information System (INIS)
2008-01-01
Full text: The economic and environmental sustainability of uranium mining has been analysed by Monash University researcher Dr Gavin Mudd in a paper that challenges the perception that uranium mining is an 'infinite quality source' that provides solutions to the world's demand for energy. Dr Mudd says information on the uranium industry touted by politicians and mining companies is not necessarily inaccurate, but it does not tell the whole story, being often just an average snapshot of the costs of uranium mining today without reflecting the escalating costs associated with the process in years to come. 'From a sustainability perspective, it is critical to evaluate accurately the true lifecycle costs of all forms of electricity production, especially with respect to greenhouse emissions, ' he says. 'For nuclear power, a significant proportion of greenhouse emissions are derived from the fuel supply, including uranium mining, milling, enrichment and fuel manufacture.' Dr Mudd found that financial and environmental costs escalate dramatically as the uranium ore is used. The deeper the mining process required to extract the ore, the higher the cost for mining companies, the greater the impact on the environment and the more resources needed to obtain the product. I t is clear that there is a strong sensitivity of energy and water consumption and greenhouse emissions to ore grade, and that ore grades are likely to continue to decline gradually in the medium to long term. These issues are critical to the current debate over nuclear power and greenhouse emissions, especially with respect to ascribing sustainability to such activities as uranium mining and milling. For example, mining at Roxby Downs is responsible for the emission of over one million tonnes of greenhouse gases per year and this could increase to four million tonnes if the mine is expanded.'
Issues in uranium availability
International Nuclear Information System (INIS)
Schanz, J.J. Jr.; Adams, S.S.; Gordon, R.L.
1982-01-01
The purpose of this publication is to show the process by which information about uranium reserves and resources is developed, evaluated and used. The following three papers in this volume have been abstracted and indexed for the Energy Data Base: (1) uranium reserve and resource assessment; (2) exploration for uranium in the United States; (3) nuclear power, the uranium industry, and resource development
Bicarbonate leaching of uranium
International Nuclear Information System (INIS)
Mason, C.
1998-01-01
The alkaline leach process for extracting uranium from uranium ores is reviewed. This process is dependent on the chemistry of uranium and so is independent on the type of mining system (conventional, heap or in-situ) used. Particular reference is made to the geochemical conditions at Crownpoint. Some supporting data from studies using alkaline leach for remediation of uranium-contaminated sites is presented
Bicarbonate leaching of uranium
Energy Technology Data Exchange (ETDEWEB)
Mason, C.
1998-12-31
The alkaline leach process for extracting uranium from uranium ores is reviewed. This process is dependent on the chemistry of uranium and so is independent on the type of mining system (conventional, heap or in-situ) used. Particular reference is made to the geochemical conditions at Crownpoint. Some supporting data from studies using alkaline leach for remediation of uranium-contaminated sites is presented.
Uranium Mill Tailings Management
International Nuclear Information System (INIS)
Nelson, J.D.
1982-01-01
This book presents the papers given at the Fifth Symposium on Uranium Mill Tailings Management. Advances made with regard to uranium mill tailings management, environmental effects, regulations, and reclamation are reviewed. Topics considered include tailings management and design (e.g., the Uranium Mill Tailings Remedial Action Project, environmental standards for uranium mill tailings disposal), surface stabilization (e.g., the long-term stability of tailings, long-term rock durability), radiological aspects (e.g. the radioactive composition of airborne particulates), contaminant migration (e.g., chemical transport beneath a uranium mill tailings pile, the interaction of acidic leachate with soils), radon control and covers (e.g., radon emanation characteristics, designing surface covers for inactive uranium mill tailings), and seepage and liners (e.g., hydrologic observations, liner requirements)
Uranium enrichment measurement task with a connectionist architecture
International Nuclear Information System (INIS)
Vigneron, V.; Martinez, J.M.; Morel, J.; Lepy, M.C.
1995-01-01
Layered Neural Networks, which are a class of models based on neural computation, are applied to the measurement of uranium enrichment, i.e. the isotope ration 235 U/( 235 U+ 236 U+ 238 U). The usual methods consider a limited number of γ-ray and X-ray peaks, and requires previously calibrated instrumentation for each sample. But, in practice, the source-detector ensemble geometry conditions are critically different, thus a means of improving the above conventional methods is to reduce the region of interest: this is possible by focusing on the region called K α X where the three elementary components are present. The measurement of these components in mixtures leads to the desired ratio. Real data are used to study its performance. Training is done with a Maximum Likelihood method. We show the encoding of data by Neural Networks is a promising method to measure uranium 235 U and 238 U quantities in infinitely thick samples. (authors). 7 refs., 2 figs., 1 tab
Brazilian uranium exploration program
International Nuclear Information System (INIS)
Marques, J.P.M.
1981-01-01
General information on Brazilian Uranium Exploration Program, are presented. The mineralization processes of uranium depoits are described and the economic power of Brazil uranium reserves is evaluated. (M.C.K.) [pt
Formation conditions for regenerated uranium blacks in uranium-molybdenum deposits
International Nuclear Information System (INIS)
Skvortsova, K.V.; Sychev, I.V.; Modnikov, I.S.; Zhil'tsova, I.G.
1980-01-01
Formation conditions of regenerated uranium blacks in the zone of incomplete oxidation and cementation of uranium-molybdenum deposit have been studied. Mixed and regenerated blacks were differed from residual ones by the method of determining excess quantity of lead isotope (Pb 206 ) in ores. Determined were the most favourable conditions for formation of regenerated uranium blacks: sheets of brittle and permeable volcanic rocks characterized by heterogeneous structure of a section, by considerable development of gentle interlayer strippings and zones of hydrothermal alteration; predominance of reduction conditions in a media over oxidation ones under limited oxygen access and other oxidating agents; the composition of hypogenic ores characterized by optimum correlations of uranium minerals, sulfides and carbonates affecting violations of pH in oxidating solutions in the range of 5-6; the initial composition of ground water resulting from climatic conditions of the region and the composition of ore-bearing strata and others. Conditions unfavourable for the formation of regenerated uranium blacks are shown
International Nuclear Information System (INIS)
Robertson, R.
1986-01-01
A flow-through apparatus has been devised to study the dissolution in simulated lung fluid of aerosol materials associated with the Canadian uranium industry. The apparatus has been experimentally applied over 16 day extraction periods to approximately 2g samples of < 38um and 53-75um particle-size fractions of both Elliot Lake and Mid-Western uranium ores. The extraction of uranium-238 was in the range 24-60% for these samples. The corresponding range for radium-226 was 8-26%. Thorium-230, lead-210, polonium-210, and thorium-232 were not significantly extracted. It was incidentally found that the elemental composition of the ores studied varies significantly with particle size, the radionuclide-containing minerals and several extractable stable elements being concentrated in the smaller size fraction. Samples of the refined compounds uranium dioxide and uranium trioxide were submitted to similar 16 day extraction experiments. Approximately 0.5% of the uranium was extracted from a 0.258g sample of unsintered (fluid bed) uranium dioxide of particle size < 38um. The corresponding figure for a 0.292g sample of uranium trioxide was 97%. Two aerosol samples on filters were also studied. Of the 88ug uranium initially measured on stage 2 of a cascade impactor sample collected from the yellow cake packing area of an Elliot Lake mill, essentially 100% was extracted over a 16 day period. The corresponding figure for an open face filter sample collected in a fuel fabrication plant and initially measured at 288ug uranium was approximately 3%. Recommendations are made with regard to further work of a research nature which would be useful in this area. Recommendations are also made on sampling methods, analytical methods and extraction conditions for various aerosols of interest which are to be studied in a work of broader scope designed to yield meaningful data in connection with lung dosimetry calculations
International Nuclear Information System (INIS)
Suzuki, Kenji; Shikama, Tatsuo; Ochiai, Akira.
1993-01-01
We developed the system for purifying uranium metal and its metallic compounds and for growing highly pure uranium compounds to study their intrinsic physical properties. Uranium metal was zone refined under low contamination conditions as far as possible. The degree of the purity of uranium metal was examined by the conventional electrical resistivity measurement and by the chemical analysis using the inductive coupled plasma emission spectrometry (ICP). The results show that some metallic impurities evaporated by the r.f. heating and other usual metallic impurities moved to the end of a rod with a molten zone. Therefore, we conclude that the zone refining technique is much effective to the removal of metallic impurities and we obtained high purified uranium metal of 99.99% up with regarding to metallic impurities. The maximum residual resistivity ratio, the r.r.r., so far obtained was about 17-20. Using the purified uranium, we are attempting to grow a highly pure uranium-titanium single crystals. (author)
Energy Technology Data Exchange (ETDEWEB)
Avril, R; Grenier, J [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires
1964-07-01
The uranium ore chemical treatment plant at Bessines-sur-Gartempe is supplied entirely by the La Crouzille Mining Division of the French Atomic Energy Commission mainly from mining districts of Fanay, Margnac and Le BRUGEAUD in the Limousin province and also, for the remainder, by a certain amount of private production in the 'Massif Central'. The supply mixture, which is very heterogeneous, is enriched before being treated chemically. The pre-concentration operation is carried out in the divisions ore treatment work-shop. It consists in a stone removal operation using radiometric sorting along a continuous belt; this makes it possible to eliminate 50 pour cent of the only fraction which is thus treated - that from 50 to 120 mm; it represents 15 to 20 per cent of the total tonnage supplied to the plant. (authors) [French] L'usine chimique de traitement des minerais d'uranium de Bessines-sur-Gartempe est entierement alimentee par la Division Miniere de La Crouzille, du Commissariat a l'Energie Atomique, principalement a partir des ensembles miniers limousins de Fanay, Margnac et du Brugenud et, pour le complement, par une certaine production privee en provenance du Massif Central. Le melange d'alimentation, tres heterogene, est enrichi avant d'etre livre a la chimie. L'operation de preconcentration est realisee dans l'atelier de preparation des minerais de la division. Il s'agit d'un epierrage par triage radiometrique sur bande, en continu, qui permet d'eliminer 50 pour cent de la seule fraction granulometrique qui le subit - le 50-120 mm - soit encore 15 a 20 pour cent du tonnage global d'alimentation livre a l'usine. (auteurs)
International Nuclear Information System (INIS)
McCarn, D.W.
2001-01-01
The Crownpoint and Churchrock uranium deposits, San Juan Basin, New Mexico are currently being developed by Uranium Resources, Inc. (URI) and its subsidiary Hydro Resources, Inc. (HRI) with an anticipated start-up in 1998. Both deposits will be developed using advanced in situ leach (ISL) mining techniques. URI/HRI currently has about 14,583 t U (37.834 million pounds U 3 O 8 ) of estimated recoverable reserves at Crownpoint and Churchrock. at a cost less than $39/kg U ($15/lb U 3 O 8 ). The uranium endowment of the San Juan Basin is the largest of any province in the USA. In March, 1997, a Final Environmental Impact Statement (FEIS) for the Crownpoint and Churchrock sites was completed by the Nuclear Regulatory Commission which recommends the issuance of an operating license. The FEIS is the culmination of a 9 year effort to license and develop the deposits. The Westwater Canyon Member of the Jurassic Morrison Formation is an arkosic, fine to coarse grained sandstone bounded by near basinwide confining clays deposited in a wet alluvial fan environment within the San Juan Basin. The primary, trend-ore deposits are hosted by the Westwater Canyon Member as humate-rich, syngenetic tabular deposits which were subsequently remobilized into roll fronts. Since deposition in the Jurassic, two phases of remobilization have occurred in the basin causing the formation of in situ leach amenable monometallic uranium rolls free of organic debris. Following in situ mining, ground water restoration of the Crownpoint and Churchrock mines is required to provide a water quality consistent with pre-mining baseline conditions. The development of in situ mining offers an environmentally sound and cost-effective method for uranium extraction. URI/HRI anticipates a production of 385-1,156 Tonnes U/year (1-3 million pounds U 3 O 8 ) from the New Mexico properties. (author)
Uranium. Resources, production and demand
International Nuclear Information System (INIS)
1997-01-01
The events characterising the world uranium market in the last several years illustrate the persistent uncertainly faced by uranium producers and consumers worldwide. With world nuclear capacity expanding and uranium production satisfying only about 60 per cent of demand, uranium stockpiles continue to be depleted at a high rate. The uncertainty related to the remaining levels of world uranium stockpiles and to the amount of surplus defence material that will be entering the market makes it difficult to determine when a closer balance between uranium supply and demand will be reached. Information in this report provides insights into changes expected in uranium supply and demand until well into the next century. The 'Red Book', jointly prepared by the OECD Nuclear Energy Agency and the International Atomic Energy Agency, is the foremost reference on uranium. This world report is based on official information from 59 countries and includes compilations of statistics on resources, exploration, production and demand as of 1 January 1997. It provides substantial new information from all of the major uranium producing centres in Africa, Australia, Eastern Europe, North America and the New Independent States, including the first-ever official reports on uranium production in Estonia, Mongolia, the Russian Federation and Uzbekistan. It also contains an international expert analysis of industry statistics and worldwide projections of nuclear energy growth, uranium requirements and uranium supply
A review of the environmental behavior of uranium derived from depleted uranium alloy penetrators
Energy Technology Data Exchange (ETDEWEB)
Erikson, R.L.; Hostetler, C.J.; Divine, J.R.; Price, K.R.
1990-01-01
The use of depleted uranium (DU) penetrators as armor-piercing projectiles in the field results in the release of uranium into the environment. Elevated levels of uranium in the environment are of concern because of radioactivity and chemical toxicity. In addition to the direct contamination of the soil with uranium, the penetrators will also chemically react with rainwater and surface water. Uranium may be oxidized and leached into surface water or groundwater and may subsequently be transported. In this report, we review some of the factors affecting the oxidation of the DU metal and the factors influencing the leaching and mobility of uranium through surface water and groundwater pathways, and the uptake of uranium by plants growing in contaminated soils. 29 refs., 10 figs., 3 tabs.
Refining of crude uranium by solvent extraction for production of nuclear pure uranium metal
International Nuclear Information System (INIS)
Gupta, S.K.; Manna, S.; Singha, M.; Hareendran, K.N.; Chowdhury, S.; Satpati, S.K.; Kumar, K.
2007-01-01
Uranium is the primary fuel material for any nuclear fission energy program. Natural uranium contains only 0.712% of 235 U as fissile constituent. This low concentration of fissile isotope in natural uranium calls for a very high level of purity, especially with respect to neutron poisons like B, Cd, Gd etc. before it can be used as nuclear fuel. Solvent extraction is a widely used technique by which crude uranium is purified for reactor use. Uranium metal plant (UMP), BARC, Trombay is engaged in refining of uranium concentrate for production of nuclear pure uranium metal for fabrication of fuel for research reactors. This paper reviews some of the fundamental aspects of this refining process with some special references to UMP, BARC. (author)
Uranium XAFS analysis of kidney from rats exposed to uranium.
Kitahara, Keisuke; Numako, Chiya; Terada, Yasuko; Nitta, Kiyohumi; Shimada, Yoshiya; Homma-Takeda, Shino
2017-03-01
The kidney is the critical target of uranium exposure because uranium accumulates in the proximal tubules and causes tubular damage, but the chemical nature of uranium in kidney, such as its chemical status in the toxic target site, is poorly understood. Micro-X-ray absorption fine-structure (µXAFS) analysis was used to examine renal thin sections of rats exposed to uranyl acetate. The U L III -edge X-ray absorption near-edge structure spectra of bulk renal specimens obtained at various toxicological phases were similar to that of uranyl acetate: their edge position did not shift compared with that of uranyl acetate (17.175 keV) although the peak widths for some kidney specimens were slightly narrowed. µXAFS measurements of spots of concentrated uranium in the micro-regions of the proximal tubules showed that the edge jump slightly shifted to lower energy. The results suggest that most uranium accumulated in kidney was uranium (VI) but a portion might have been biotransformed in rats exposed to uranyl acetate.
International Nuclear Information System (INIS)
Wu Lieqin; Tan Zhengzhong
2004-01-01
Based on analyzing the prospecting potential for uranium deposits in Xiazhuang uranium ore field this paper discusses the prospecting for rich uranium deposits and prospecting potential in the region. Research achievements indicate: that the Xiazhuang ore-field is an ore-concentrated area where uranium has been highly enriched, and possesses good prospecting potential and perspective, becoming one of the most important prospecting areas for locating rich uranium deposits in northern Guangdong; that the 'intersection type', the alkaline metasomatic fractured rock type and the vein-group type uranium deposits are main targets and the prospecting direction for future uranium prospecting in this region
Energy Technology Data Exchange (ETDEWEB)
Achatz, M. [Bundesamt fuer Strahlenschutz, Berlin (Germany); Urso, L. [Bundesamt fuer Strahlenschutz, Oberschleissheim (Germany)
2016-07-01
87 % of mineral phosphate fertilizers are produced of sedimentary rock phosphate, which generally contains heavy metals, like uranium. The solution and migration behavior of uranium is apart from its redox ratio, determined by its pH conditions as well as its ligand quality and quantity. A further important role in sorption is played by soil components like clay minerals, pedogenic oxides and soil organic matter. To provide a preferably detailed speciation model of U in soil several physical and chemical components have to be included to be able to state distribution coefficients (k{sub D}) and sorption processes. The model of Hormann and Fischer served as the basis of modelling uranium mobility in soil by using the program PhreeqC. The usage of real soil and soil water measurements may contribute to identify factors and processes influencing the mobility of uranium under preferably realistic conditions. Additionally, the assessment of further predictions towards uranium migration in soil can be made based on a modelling with PhreeqC. The modelling of uranium inputs and its fate in soil can help to elucidate the human caused occurrence or geogenic origin of uranium in soil.
International Nuclear Information System (INIS)
1983-01-01
On a country by country basis the International Uranium Resources Evaluation Project (IUREP) estimates 1982-1983 are reviewed. Information provided includes exploration work, airborne survey, radiometric survey, gamma-ray spectrometric survey, estimate of speculative resources, uranium occurrences, uranium deposits, uranium mineralization, agreements for uranium exploration, feasibilities studies, geological classification of resources, proposed revised resource range, production estimate of uranium
Energy Technology Data Exchange (ETDEWEB)
1986-01-01
The report on the uranium market describes the technical and economic factors influencing the nuclear fuel industry in mid-1986. The contents of the report includes a discussion of: the nuclear generating capacity, the demand for uranium (requirements and procurements), supplies of uranium, and the interaction between supply and demand. The report does not study in depth the effects of the Chernobyl accident on the uranium market.
International Nuclear Information System (INIS)
1994-09-01
Uranium production in the United States has declined dramatically from a peak of 43.7 million pounds U 3 O 8 (16.8 thousand metric tons uranium (U)) in 1980 to 3.1 million pounds U 3 O 8 (1.2 thousand metric tons U) in 1993. This decline is attributed to the world uranium market experiencing oversupply and intense competition. Large inventories of uranium accumulated when optimistic forecasts for growth in nuclear power generation were not realized. The other factor which is affecting U.S. uranium production is that some other countries, notably Australia and Canada, possess higher quality uranium reserves that can be mined at lower costs than those of the United States. Realizing its competitive advantage, Canada was the world's largest producer in 1993 with an output of 23.9 million pounds U 3 O 8 (9.2 thousand metric tons U). The U.S. uranium industry, responding to over a decade of declining market prices, has downsized and adopted less costly and more efficient production methods. The main result has been a suspension of production from conventional mines and mills. Since mid-1992, only nonconventional production facilities, chiefly in situ leach (ISL) mining and byproduct recovery, have operated in the United States. In contrast, nonconventional sources provided only 13 percent of the uranium produced in 1980. ISL mining has developed into the most cost efficient and environmentally acceptable method for producing uranium in the United States. The process, also known as solution mining, differs from conventional mining in that solutions are used to recover uranium from the ground without excavating the ore and generating associated solid waste. This article describes the current ISL Yang technology and its regulatory approval process, and provides an analysis of the factors favoring ISL mining over conventional methods in a declining uranium market
Energy Technology Data Exchange (ETDEWEB)
1994-09-01
Uranium production in the United States has declined dramatically from a peak of 43.7 million pounds U{sub 3}O{sub 8} (16.8 thousand metric tons uranium (U)) in 1980 to 3.1 million pounds U{sub 3}O{sub 8} (1.2 thousand metric tons U) in 1993. This decline is attributed to the world uranium market experiencing oversupply and intense competition. Large inventories of uranium accumulated when optimistic forecasts for growth in nuclear power generation were not realized. The other factor which is affecting U.S. uranium production is that some other countries, notably Australia and Canada, possess higher quality uranium reserves that can be mined at lower costs than those of the United States. Realizing its competitive advantage, Canada was the world`s largest producer in 1993 with an output of 23.9 million pounds U{sub 3}O{sub 8} (9.2 thousand metric tons U). The U.S. uranium industry, responding to over a decade of declining market prices, has downsized and adopted less costly and more efficient production methods. The main result has been a suspension of production from conventional mines and mills. Since mid-1992, only nonconventional production facilities, chiefly in situ leach (ISL) mining and byproduct recovery, have operated in the United States. In contrast, nonconventional sources provided only 13 percent of the uranium produced in 1980. ISL mining has developed into the most cost efficient and environmentally acceptable method for producing uranium in the United States. The process, also known as solution mining, differs from conventional mining in that solutions are used to recover uranium from the ground without excavating the ore and generating associated solid waste. This article describes the current ISL Yang technology and its regulatory approval process, and provides an analysis of the factors favoring ISL mining over conventional methods in a declining uranium market.
Uranium: biokinetics and toxicity; Biocinetique et toxicite de l'uranium
Energy Technology Data Exchange (ETDEWEB)
Menetrier, F.; Renaud-Salis, V.; Flury-Herard, A
2000-07-01
This report was achieved as a part of a collaboration with the Fuel Cycle Direction. Its aim was to give the state of the art about: the behaviour of uranium in the human organism (biokinetics) after ingestion, its toxicity (mainly renal) and the current regulation about its incorporation. Both in the upstream and in the downstream of the fuel cycle, uranium remains, quantitatively, the first element in the cycle which is, at the present time, temporarily disposed or recycled. Such a considerable quantity of uranium sets the problem of its risk on the health. In the long term, the biosphere may be affected and consequently the public may ingest water or food contaminated with uranium. In this way, radiological and chemical toxicity risk may be activated. This report emphasizes: the necessity of confirming some experimental and epidemiological biokinetic data used or not in the ICRP models. Unsolved questions remain about the gastrointestinal absorption according to chemical form (valency state, mixtures...), mass and individual variations (age, disease) further a chronic ingestion of uranium. It is well established that uranium is mainly deposited in the skeleton and the kidney. But the skeleton kinetics following a chronic ingestion and especially in some diseases has to be more elucidated; the necessity of taking into account uranium at first as a chemical toxic, essentially in the kidney and determining the threshold of functional lesion. In this way, it is important to look for some specific markers; the problem of not considering chemical toxicity of uranium in the texts regulating its incorporation.
Airborne uranium, its concentration and toxicity in uranium enrichment facilities
International Nuclear Information System (INIS)
Thomas, J.; Mauro, J.; Ryniker, J.; Fellman, R.
1979-02-01
The release of uranium hexafluoride and its hydrolysis products into the work environment of a plant for enriching uranium by means of gas centrifuges is discussed. The maximum permissible mass and curie concentration of airborne uranium (U) is identified as a function of the enrichment level (i.e., U-235/total U), and chemical and physical form. A discussion of the chemical and radiological toxicity of uranium as a function of enrichment and chemical form is included. The toxicity of products of UF 6 hydrolysis in the atmosphere, namely, UO 2 F 2 and HF, the particle size of toxic particulate material produced from this hydrolysis, and the toxic effects of HF and other potential fluoride compounds are also discussed. Results of an investigation of known effects of humidity and temperature on particle size of UO 2 F 2 produced by the reaction of UF 6 with water vapor in the air are reported. The relationship of the solubility of uranium compounds to their toxic effects was studied. Identification and discussion of the standards potentially applicable to airborne uranium compounds in the working environment are presented. The effectiveness of High Efficiency Particulate (HEPA) filters subjected to the corrosive environment imposed by the presence of hydrogen fluoride is discussed
International Nuclear Information System (INIS)
Wiencek, T.C.; Domagala, R.F.; Thresh, H.R.
1990-01-01
Two embodiments of a high uranium fuel plate are disclosed which contain a meat comprising structured uranium compound confined between a pari of diffusion bonded ductile metal cladding plates uniformly covering the meat, the meat hiving a uniform high fuel loading comprising a content of uranium compound greater than about 45 Vol. % at a porosity not greater than about 10 Vol. %. In a first embodiment, the meat is a plurality of parallel wires of uranium compound. In a second embodiment, the meat is a dispersion compact containing uranium compound. The fuel plates are fabricated by a hot isostatic pressing process