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Sample records for cimarron uranium plant

  1. Decontamination and decommissioning of the Kerr-McGee Cimarron Plutonium Fuel Plant

    Energy Technology Data Exchange (ETDEWEB)

    1994-05-01

    This final report is a summary of the events that completes the decontamination and decommissioning of the Cimarron Corporation`s Mixed Oxides Fuel Plant (formally Sequoyah Fuels Corporation and formerly Kerr-McGee Nuclear Corporation - all three wholly owned subsidiaries of the Kerr-McGee Corporation). Included are details dealing with tooling and procedures for performing the unique tasks of disassembly decontamination and/or disposal. That material which could not be economically decontaminated was volume reduced by disassembly and/or compacted for disposal. The contaminated waste cleaning solutions were processed through filtration and ion exchange for release or solidified with cement for L.S.A. waste disposal. The L.S.A. waste was compacted, and stabilized as required in drums for burial in an approved burial facility. T.R.U. waste packaging and shipping was completed by the end of July 1987. This material was shipped to the Hanford, Washington site for disposal. The personnel protection and monitoring measures and procedures are discussed along with the results of exposure data of operating personnel. The shipping containers for both T.R.U. and L.S.A. waste are described. The results of the decommissioning operations are reported in six reports. The personnel protection and monitoring measures and procedures are contained and discussed along with the results of exposure data of operating personnel in this final report.

  2. Uranium Fuel Plant. Applicants environmental report

    International Nuclear Information System (INIS)

    The Uranium Fuel Plant, located at the Cimarron Facility, was constructed in 1964 with operations commencing in 1965 in accordance with License No. SNM-928, Docket No. 70-925. The plant has been in continuous operation since the issuance of the initial license and currently possesses contracts extending through 1978, for the production of nuclear fuels. The Uranium Plant is operated in conjunction with the Plutonium Facility, each sharing common utilities and sanitary wastes disposal systems. The operation has had little or no detrimental ecological impact on the area. For the operation of the Uranium Fuel Fabrication Plant, initial equipment provided for the production of UO2, UF4, uranium metal and recovery of scrap materials. In 1968, the plant was expanded by increasing the UO2 and pellet facilities by the installation of another complete production line for the production of fuel pellets. In 1969, fabrication facilities were added for the production of fuel elements. Equipment initially installed for the recovery of fully enriched scrap has not been used since the last work was done in 1970. Economically, the plant has benefited the Logan County area, with approximately 104 new jobs with an annual payroll of approximately $1.3 million. In addition, $142,000 is annually paid in taxes to state, local and federal governments, and local purchases amount to approximately $1.3 million. This was all in land that was previously used for pasture land, with a maximum value of approximately 37,000 dollars. Environmental effects of plant operation have been minimal. A monitoring and measurement program is maintained in order to ensure that the ecology of the immediate area is not affected by plant operations

  3. Uranium speciation in plants

    International Nuclear Information System (INIS)

    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.)

  4. Chemwes Uranium Plant

    International Nuclear Information System (INIS)

    The Chemwes Uranium Plant is located in an area which is underlain to a major extent by pinnacled dolomite. It was decided to adopt a replacement fill for support of light structures in preference to alternatives such as the installation of piles or 'bridging' between pinnacles. The 3 m thick soil 'raft' resulting from the fill replacement technique made it possible to support all but a very small number of foundations upon shallow spread footings or raft slabs. This article describes a replacement fill for support of light structures at the Chemwes Uranium Plant

  5. Decommissioning of uranium conversion plant

    International Nuclear Information System (INIS)

    Since about 20 years have passed after the construction of the uranium conversion plant, most equipments installed have worn out. Liquid wastes stored in lagoons which were generated during the operation of this plant are needed to be treated safely. Therefore, the decommissioning project on the uranium conversion plant was started from 2001. This study is a preliminary step for the decommissioning of the uranium conversion plant. It was reviewed on the plant status overall, especially facility descriptions and operational histories for the installations located inside and outside of the plant and methods of decontamination and of dismantling to the contamination conditions. And some proper options on each main object was proposed

  6. Vaal Reefs South uranium plant

    International Nuclear Information System (INIS)

    The Vaal Reefs mining complex, part of the Anglo American Corporation, is the largest gold and uranium producing complex in the world, being South Africa's principal producer, accounting for about a quarter of the country's uranium production. Vaal Reefs South uranium plant in the Orkney district was recently officially opened by Dr AJA Roux, the retiring president of the Atomic Energy Board and chairman of the Uranium Enrichment Corporation and will increase the country's uranium production. In the field of technology, and particularly processing technology, South Africa has shown the world unprecedented technology achievement in the field of uranium extraction from low grade ores and the development of the unique uranium enrichment process. New technical innovations that have been incorporated in this new plant are discussed

  7. Uranium uptake by hydroponically cultivated crop plants

    International Nuclear Information System (INIS)

    Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC50 value about 0.1 mM. Cucumis sativa represented the most resistant plant to uranium (EC50 = 0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1 mM. Twenty different plant species were tested in hydroponic solution supplemented by 0.1 mM or 0.5 mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation. - Highlights: → The uranium accumulation in twenty different plant species varied from 0.160 to 0.011 mg/g DW. → Uranium is mainly localized in the root system. → Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba. → The phosphates deficiency increase the uranium uptake.

  8. Uranium uptake by hydroponically cultivated crop plants

    Energy Technology Data Exchange (ETDEWEB)

    Soudek, Petr; Petrova, Sarka [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Benesova, Dagmar [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Faculty of Environment Technology, Institute of Chemical Technology, Technicka 5, 166 28 Prague 6 (Czech Republic); Dvorakova, Marcela [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic); Vanek, Tomas, E-mail: vanek@ueb.cas.cz [Laboratory of Plant Biotechnologies, Joint Laboratory of Institute of Experimental Botany AS CR, v.v.i. and Crop Research Institute, v.v.i., Rozvojova 263, 162 05 Prague 6 (Czech Republic)

    2011-06-15

    Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC{sub 50} value about 0.1 mM. Cucumis sativa represented the most resistant plant to uranium (EC{sub 50} = 0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1 mM. Twenty different plant species were tested in hydroponic solution supplemented by 0.1 mM or 0.5 mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation. - Highlights: > The uranium accumulation in twenty different plant species varied from 0.160 to 0.011 mg/g DW. > Uranium is mainly localized in the root system. > Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba. > The phosphates deficiency increase the uranium uptake.

  9. Uranium hexafluoride production plant decommissioning

    International Nuclear Information System (INIS)

    The Institute of Energetic and Nuclear Research - IPEN is a research and development institution, located in a densely populated area, in the city of Sao Paulo. The nuclear fuel cycle was developed from the Yellow Cake to the enrichment and reconversion at IPEN. After this phase, all the technology was transferred to private enterprises and to the Brazilian Navy (CTM/SP). Some plants of the fuel cycle were at semi-industrial level, with a production over 20 kg/h. As a research institute, IPEN accomplished its function of the fuel cycle, developing and transferring technology. With the necessity of space for the implementation of new projects, the uranium hexafluoride (UF6) production plant was chosen, since it had been idle for many years and presented potential leaking risks, which could cause environmental aggression and serious accidents. This plant decommission required accurate planning, as this work had not been carried out in Brazil before, for this type of facility, and there were major risks involving gaseous hydrogen fluoride aqueous solution of hydrofluoric acid (HF) both highly corrosive. Evaluations were performed and special equipment was developed, aiming to prevent leaking and avoid accidents. During the decommissioning work, the CNEN safety standards were obeyed for the whole operation. The environmental impact was calculated, showing to be not relevant.The radiation doses, after the work, were within the limits for the public and the area was released for new projects. (author)

  10. Design of a uranium recovery pilot plant

    International Nuclear Information System (INIS)

    The engineering design of a pilot plant of uranium recover, is presented. The diagrams and specifications of the equipments such as pipelines, pumps, values tanks, filters, engines, etc... as well as metallic structure and architetonic design is also presented. (author)

  11. Uranium refining and conversion plant decommissioning project

    International Nuclear Information System (INIS)

    The uranium refining and conversion plant (URCP) at Ningyo-toge was constructed in 1981 for the purpose of demonstrating on refining and conversion process from yellow cake (or uranium trioxide) to uranium hexafluoride by way of uranium tetrafluoride. For 20 years, 385 tons of natural uranium hexafluoride and 336 tons of reprocessed uranium hexafluoride (approximately) was produced. There are two different type of refining processes in the URCP. One is the wet process by converting the natural uranium and the other is the dry conversion process for the reprocessed uranium. The dismantling of the dry process facilities began in March, 2008. It was found the large amount of uranium residuals such as wet slurry and powder uranium inside the vessels and pipes. Therefore, we have to take care of the spread of the contamination during dismantling works. The basic strategy concerning plant dismantling were the optimization of the total labor costs and the minimization of the radioactive wastes generated. The dismantling procedure is shown below; 1) measuring doserate by using high sensitivity surveymeters, and nuclide identification by using gamma ray spectrometry, 2) estimating uranium mass inventory, 3) planning work force distributions with radiological survey staffs, 4) deciding dismantling methods concretely, 5) decontaminating schematically if required, 6) collecting detailed data of working conditions, 7) measuring and classifying contaminated materials, 8) managements of radioactive waste drum and non-contaminated equipment, 9) control for personal exposures. Almost all equipment will be decontaminated except building decontamination it by around 2013FY. In addition, the secondary wastes were also yielded. Few thousands man-days were necessary for this project. The measurement data have not showed the high environmental radiation doserate, generally less than 0.3μSv/h. However, by the trace of the reprocessed uranium, the trans-uranium nuclides such as uranium

  12. Decommissioning of an uranium hexafluoride pilot plant

    International Nuclear Information System (INIS)

    The Institute of Nuclear and Energetic Researches has completed fifty years of operation, belongs to the National Commission for Nuclear Energy, it is situated inside the city of Sao Paulo. The IPEN-CNEN/SP is a Brazilian reference in the nuclear fuel cycle, researches in this field began in 1970, having dominance in the cycle steps from Yellow Cake to Uranium Hexafluoride technology. The plant of Uranium Hexafluoride produced 35 metric tonnes of this gas by year, had been closed in 1992, due to domain and total transference of know-how for industrial scale, demand of new facilities for the improvement of recent researches projects. The Institute initiates decommissioning in 2002. Then, the Uranium Hexafluoride pilot plant, no doubt the most important unit of the fuel cycle installed at IPEN-CNEN/SP, beginning decommissioning and dismantlement (D and D) in 2005. Such D and D strategies, planning, assessment and execution are described, presented and evaluated in this paper. (author)

  13. The Chemwes uranium plant: A case history

    International Nuclear Information System (INIS)

    During the 1970s when the Nuexco exchange value for U3O8 rose from US $6 to $43 per pound, the recovery of uranium from even comparatively low grade deposits appeared to be attractive. Two mines in the Klerksdorp area of the Republic of South Africa, Stilfontein and Buffelsfontein, had been stockpiling uranium bearing tailings material since the early 1960s, and initial sampling of these and other smaller sources of residue in the area suggested that the establishment of a central uranium beneficiation plant to process such material would be economically feasible. Preliminary studies showed that the uranium content of the tailings could not be economically concentrated before leaching, but that the pyrite in the plant tailings could possibly be concentrated by flotation, with subsequent roasting to provide both the acid needed in the uranium dissolution process and a calcine product from which gold could be recovered. A preliminary feasibility study suggested that an operation of 270 kt per month would be the most attractive in economic terms. It was decided that a contract for the expected production should be negotiated so that this security could be used to support the financing of the project. The paper gives a description of the performance of the plant so far. The plant performance is analysed from the processing and the mechanical points of view, with special emphasis on the leaching, solid-liquid separation, recovery, and purification sections. The criteria used in the initial selection of the process are reviewed and compared with the subsequent performance of the plant. (author). 2 refs, 4 figs, 2 tabs

  14. Status of Uranium Conversion Plant Decommissioning

    International Nuclear Information System (INIS)

    KAERI (Korea Atomic Energy Research Institute) constructed a pilot plant for the uranium conversion process for the development of the technologies and the localization of nuclear fuels for HWR (heavy water reactor) in 1982. The final product of the plant was a UO2 powder of ceramic grade for HWR and its capacity was 100 ton-U/year. After that, a part of the AUC (Ammonium Uranyl Carbonate) process was added and the process was improved for automatic operation. 320 tons of UO2 powder was produced and supplied to the fabrication plant at KAERI for the fuel of the Wolsong-1 CANDU (Canadian deuterium uranium) reactor. The conversion plant has building area of 2916 m2 and two main conversion processes. ADU (Ammonium Di-Uranate) and AUC process are installed in the backside and the front side of the building, respectively. Conversion plant has two lagoons, which is to store all wastes generated from the plant operation. Sludge wastes stored 150m3 and 100m3 in Lagoon 1 and 2, respectively. Main compounds of sludge are ammonium nitrate, sodium nitrate, calcium nitrate, and calcium carbonate. In early 1992, it was determined that the plant operation would be stopped due to a much higher production cost than that of the international market. The conversion plant has been shutdown and minimally maintained for the prevention of contamination by deterioration of the equipment and the lagoon

  15. NRC licensing of uranium enrichment plants

    International Nuclear Information System (INIS)

    The US Nuclear Regulatory Commission (NRC) is preparing a rule making that establishes the licensing requirements for low-enriched uranium enrichment plants. Although implementation of this rule making is timed to correspond with receipt of a license application for the Louisiana Energy Services centrifuge enrichment plant, the rule making is applicable to all uranium enrichment technologies. If ownership of the US gaseous diffusion plants and/or atomic vapor laser isotope separation is transferred to a private or government corporation, these plants also would be licensable under the new rule making. The Safeguards Studies Department was tasked by the NRC to provide technical assistance in support of the rule making and guidance preparation process. The initial and primary effort of this task involved the characterization of the potential safeguards concerns associated with a commercial enrichment plant, and the licensing issues associated with these concerns. The primary safeguards considerations were identified as detection of the loss of special nuclear material, detection of unauthorized production of material of low strategic significance, and detection of production of uranium enriched to >10% 235U. The primary safeguards concerns identified were (1) large absolute limit of error associated with the material balance closing, (2) the inability to shutdown some technologies to perform a cleanout inventory of the process system, and (3) the flexibility of some technologies to produce higher enrichments. Unauthorized production scenarios were identified for some technologies that could prevent conventional material control and accounting programs from detecting the production and removal of 5 kg 235U as highly enriched uranium. Safeguards techniques were identified to mitigate these concerns

  16. Assimilation of uranium by wheat and tomato plants

    International Nuclear Information System (INIS)

    Greenhouse conditions have been used for the study of uptake of uranium by wheat and tomato plants as affected by its concentration in soil and irrigation applied. The highest yield of wheat was obtained at 3.0 ppm of uranium whereas the tomato yield decreased with the increase of uranium in the soil. The analysis shows that Uranium uptake by wheat and tomato not only depends upon the uranium concentration in the soil but also on the amount of irrigation applied. (orig.)

  17. Uranium enrichment plant risk analysis

    International Nuclear Information System (INIS)

    A method for risk analysis of enrichment facilities is presented and applied to a small scale ultracentrifuge plant. Internal events are identified and the consequences of accidental releases of U F6 are quantified in terms of its toxicological and radiological impact. It is shown that releases in the feed and the cascade areas offers no hazards to the public . Releases of liquefied U F6 in the withdrawal areas, associated with failures in the building isolation systems, may cause undesirable consequences. (author). 11 refs, 4 figs, 3 tabs

  18. Plant-uptake of uranium: Hydroponic and soil system studies

    Science.gov (United States)

    Ramaswami, A.; Carr, P.; Burkhardt, M.

    2001-01-01

    Limited information is available on screening and selection of terrestrial plants for uptake and translocation of uranium from soil. This article evaluates the removal of uranium from water and soil by selected plants, comparing plant performance in hydroponic systems with that in two soil systems (a sandy-loam soil and an organic-rich soil). Plants selected for this study were Sunflower (Helianthus giganteus), Spring Vetch (Vicia sativa), Hairy Vetch (Vicia villosa), Juniper (Juniperus monosperma), Indian Mustard (Brassica juncea), and Bush Bean (Phaseolus nanus). Plant performance was evaluated both in terms of the percent uranium extracted from the three systems, as well as the biological absorption coefficient (BAC) that normalized uranium uptake to plant biomass. Study results indicate that uranium extraction efficiency decreased sharply across hydroponic, sandy and organic soil systems, indicating that soil organic matter sequestered uranium, rendering it largely unavailable for plant uptake. These results indicate that site-specific soils must be used to screen plants for uranium extraction capability; plant behavior in hydroponic systems does not correlate well with that in soil systems. One plant species, Juniper, exhibited consistent uranium extraction efficiencies and BACs in both sandy and organic soils, suggesting unique uranium extraction capabilities.

  19. Uranium in Dartmoor plants of southwest England

    International Nuclear Information System (INIS)

    A number of plants from Dartmoor, SW England, were investigated for their U contents. Uranium concentrations in the substrate ranged from 7.8 μg/g in the granite bedrock to 2.8 μg/g in the A horizon. Heather, gorse, bracken and a number of grasses growing in this substrate were sampled and analysed. Among these heather and gorse contained average U concentrations of 0.14 μg/g and 0.13 μg/g, respectively. Bracken and grasses have levels below the detection threshold of 0.02 μg/g. 9 refs.; 1 figure; 3 tabs

  20. 75 FR 38809 - Southern Turner Cimarron I, LLC; Notice of Filing

    Science.gov (United States)

    2010-07-06

    ... Energy Regulatory Commission Southern Turner Cimarron I, LLC; Notice of Filing June 25, 2010. Take notice that on June 24, 2010, Southern Turner Cimarron I, LLC filed a supplement confirming passive ownership... in accordance with Rules 211 and 214 of the Commission's Rules of Practice and Procedure (18 CFR...

  1. The Ellweiler uranium plant - a demolition and recycling project

    International Nuclear Information System (INIS)

    The uranium plant at Ellweiler, district of Birkenfeld, was used for the production and storage of uranium concentrates. The owner of the Ellweiler uranium plant (UAE), Gewerkschaft Brunhilde GmbH, ceased processing uranium ore and recycling in 1989 and has been in liquidation since September 1991. The State of Rhineland-Palatinate, had safety measures adopted in a first step, getting the plant into a safe state by former plant personnel. The entire plant was demolished in a second step. The contract for demolishing the former uranium plant was awarded to ABB Reaktor as the general contractor in August 1996. Demolition work was carried out between April 1997 and May 1999. A total of approx. 7900 Mg of material was disposed of. At present, recultivation measures are being carried out. (orig.)

  2. Evaluation of economical at a uranium enrichment demonstration plant

    International Nuclear Information System (INIS)

    In this report, the economy of technical achievement apply in the uranium enrichment demonstration plant is evaluated. From the evaluation, it can be concluded that the expected purpose was achieved because there was a definite economic prospect to commercial plant. The benefit analysis of thirteen years operation of the uranium enrichment demonstration plant also provides a financial aspect of the uranium enrichment business. Therefore, the performance, price and reliability of the centrifuge is an important factor in the uranium enrichment business. And the continuous development of a centrifuge while considering balance with the development cost is necessary for the business in the future. (author)

  3. Integrated design of SIGMA uranium enrichment plants

    International Nuclear Information System (INIS)

    In the present work, we describe a preliminary analysis of the design feedbacks in a Uranium Enrichment Plant, using the SIGMA concept. Starting from the result of this analysis, a computer code has been generated, which allows finding the optimal configurations of plants, for a fixed production rate. The computer code developed includes the model of the Thermohydraulic loop of a SIGMA module. The model contains numerical calculations of the main components of the circuit. During the calculations, the main components are dimensioned, for a posterior cost compute. The program also makes an estimation of the enrichment gain of the porous membrane, for each separation stage. Once the dimensions of the main components are known, using the enrichment cascade calculation, the capital and operation costs of the plant could be determined. At this point it is simple to calculate a leveled cost of the Separative Work Unit (SWU). A numerical optimizer is also included in the program. This optimizer finds the optimal cascade configuration, for a given set of design parameters. The whole-integrated program permits to investigate in detail the feedback in the component design. Therefore, the sensibility of the more relevant parameters can be computed, with respect of the economical variables of the plant. (author)

  4. Biosolubilization of uranyl ions in uranium ores by hydrophyte plants

    International Nuclear Information System (INIS)

    This paper investigated the bioleaching of uranyl ions from uranium ores, in aqueous medium by hydrophyte plants: Lemna minor, Azolla caroliniana and Elodea canadensis under different experimental conditions. The oxidation of U(IV) to U(VI) species was done by the atomic oxygen generated in the photosynthesis process by the aquatic plants in the solution above uranium ores. Under identical experimental conditions, the capacity of bioleaching of uranium ores decreases according to the following series: Lemna minor > Elodea canadensis > Azolla caroliniana. The results of IR spectra suggest the possible use of Lemna minor and Elodea canadensis as a biological decontaminant of uranium containing wastewaters. (author)

  5. Removal of uranium from uranium plant wastewater using zero-valent iron in an ultrasonic field

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jing; Zhang, Libo; Peng, Jinhui; Ma, Aiyuan; Xia, Hong Ying; Guo, Wen Qian; Yu, Xia [Yunnan Provincial Key Laboratory of Intensification Metallurgy, Kunming (China); Hu, Jinming; Yang, Lifeng [Nuclear Group Two Seven Two Uranium Industry Limited Liability Company, Hengyang (China)

    2016-06-15

    Uranium removal from uranium plant wastewater using zero-valent iron in an ultrasonic field was investigated. Batch experiments designed by the response surface methodology (RSM) were conducted to study the effects of pH, ultrasonic reaction time, and dosage of zero-valent iron on uranium removal efficiency. From the experimental data obtained in this work, it was found that the ultrasonic method employing zero-valent iron powder effectively removes uranium from uranium plant wastewater with a uranium concentration of 2,772.23 μg/L. The pH ranges widely from 3 to 7 in the ultrasonic field, and the prediction model obtained by the RSM has good agreement with the experimental results.

  6. Estimation of uranium in some edible and commercial plants

    International Nuclear Information System (INIS)

    The trace contents of uranium have been estimated in some edible and commercial plants by PTA (particle track analysis) method. The groups of food plants studied are cereals, pulses, underground vegetables, leafy vegetables, and fruit vegetables. The commercial plants and ingredients taken are betel leaves, tobacco leaves, areca nuts, and lime. Among the different samples studied, the average uranium content, in general, is found to vary from 0.25 to 2.67 ppm. (author). 10 refs., 2 tabs., 1 fig

  7. Estimation of Uranium in Some Edible and Commercial Plants

    Directory of Open Access Journals (Sweden)

    S. Choudhury

    1992-10-01

    Full Text Available The trace contents of uranium have been estimated in some edible and commercial plants by PTA method. The groups of food plants studied are cereals, pulses, underground vegetables, leafy vegetables, and fruit vegetables. The commercial plants and ingredients taken are betel leaves, tobacco leaves, areca nuts, and lime. Among the different samples studied, the average uranium content, in general, is found to vary from 0.25 to 2.67 ppm

  8. Innovations over old plant techniques in Jaduguda Uranium Mill expansion

    International Nuclear Information System (INIS)

    India's first Uranium Mines and Mills was commissioned at Jaduguda in 1968. The plant's flowsheet was developed at BARC after extensive tests, for extraction of uranium as yellow cake from the ore. The designed capacity of the process plant was initially 1000 MT/day of ore treatment supplied from nearby mines. Subsequently, due to growing demand of uranium fuel, opening of Bhatin mines and setting up of three plants for recovery of uranium mineral from copper tailings of Hindustan Copper Ltd. was perceived. The capacity of the Jaduguda Plant was increased to 1400 MT/day in 1987 to meet this requirement. A new mine at Narwapahar is under development which will necessitate augmentation of the capacity of the Jaduguda plant by 700 MT/day. Major changes are contemplated in equipment selection for the expansion besides incorporation of a high degree of automation based on microprocessor technology which are discussed in this paper. (author)

  9. Evaluation of the uranium immobilization potential of vetiver plants grown on processed solid waste of uranium industry of Jaduguda, India

    International Nuclear Information System (INIS)

    Remediation of contaminated sites using specific plant or plant groups may offer a cheap, renewable and promising technique to minimize the long-term ecological adverse impact of the waste disposal. The major components of process waste of uranium industry are uranium series radionuclides, heavy metals inherently present in the ore, chemical additives and residual uranium. Among the radionuclides quantitative content of residual uranium is highest in the disposed process waste of uranium mill. In view of this fact experiments were conducted to study the uranium immobilization potential of a phytoremediator that can grow and survive in the complex tailings (fine solid process waste) environment. Vetiver grass (Chrysopogon zizanioides (L.) Nash) was selected for translocation and immobilization studies of uranium. The grass was planted in uranium mill tailing ponds at Jaduguda, Jharkhand, India and periodic sampling was carried out to investigate the extent of uranium uptake. The acid aliquot of dry or wet ash samples of plant and soil were subjected to solvent extraction followed by UV-Fluorimetry for uranium estimation. It has been observed that the grass could immobilize up to 8 ppm uranium within 6 months after planting. Uranium is preferably immobilized at the root and translocation of uranium to upper plant parts (shoot) is low compared to roots. The uranium uptake got saturated after a particular concentration range. The increased level of uranium in the soil covering of tailings needs further investigation. (author)

  10. Treatment of uranium bearing waste arising from solvent recovery unit of uranium processing plant

    International Nuclear Information System (INIS)

    During the regeneration of tributyl phosphate in uranium plant, a sizable volume of liquid waste containing about 70 mg/l of uranium, along with high concentrations of nitrates and carbonates, is generated. Laboratory studies revealed that the waste was not amenable to conventional treatment methods, including co-precipitation, owing to high concentration of carbonates, with which uranium forms a stable carbonato complex. Various commmercially available strongly basic anion exchangers were evaluated for the uptake of uranium from the waste under static conditions. Column studies, employing the anion-exchange resin which has shown the highest uptake, were carried out. These studies reveal the application potential of ion-exchange process not only in the treatment of uranium bearing wastes but also in the recovery of uranium. (author). 8 refs., 4 figs., 5 tabs

  11. Chemical treatment of ammonium fluoride solution in uranium reconversion plant

    International Nuclear Information System (INIS)

    A chemical procedure is described for the treatment of the filtrate, produced from the transformation of uranium hexafluoride (U F6) into ammonium uranyl carbonate (AUC). This filtrate is an intermediate product in the U F6 to uranium dioxide (U O2) reconversion process. The described procedure recovers uranium as ammonium peroxide fluoro uranate (APOFU) by precipitation with hydrogen peroxide (H2 O2), and as later step, its calcium fluoride (CaF2) co-precipitation. The recovered uranium is recycled to the AUC production plant. (author)

  12. The first six years of the Chemwes uranium plant

    International Nuclear Information System (INIS)

    The Stilfontein and Buffelsfontein Gold Mines, near Klerksdorp in the Transvaal, had accumulated a large amount of uranium-containing residue and, when the price of uranium rose in the 1970s, consideration was given to the possible recovery of this uranium. Preliminary tests showed that concentration of the uranium prior to leaching would not be economic. However, the pyrite in the residue could be concentrated by flotation, and the flotation concentrate could be roasted to provide both enough acid for leaching the uranium and a calcine from which the gold could be recovered. The feasibility study showed that a uranium operation of 270 kt per month would be most economically attractive, and a plant of that size was accordingly designed and built. In the first six years of its existence, the plant treated over 20 Mt of residue and produced about 3,5 kt of uranium oxide. During that time, the plant was continually being improved to make it more reliable and cost-efficient. This paper analyses the operation of the plant during its first six years from the viewpoints of its mechanical, process, and economic performance. The criteria on which the selection of the process was based are reviewed and compared with the actual performance of the plant, emphasis being placed on the leaching, solid-liquid separation, recovery, and purification stages

  13. Uptake of uranium by plants growing on and around uranium mill tailings pond at Jaduguda, India

    International Nuclear Information System (INIS)

    A field study was conducted in an area where uranium mill tailings are discharged in the form of slurry (mixture of fine sand and effluent). The fine tailings sand is retained there and effluent is decanted for further treatment. Over the years, certain plant species like Typha latifolia, Saccharum spontanium, Ipomoea carnia etc. have covered the major portion of the tailings pond. Concentration and concentration ratio of uranium in different organs of these plants were evaluated. Concentration of uranium in Typha latifolia plant from tailings pond and the CR was found to have inverse relationship with substrate uranium content. Correlation coefficient between CR(R) and soil, CR(St) and soil and CR(L) and soil in Typha latifolia was -0.80, -0.90 and -0.86 respectively. (author)

  14. Production of 450 kg uranium metal ingot in Augmented Uranium Metal Plant (AUMP)

    International Nuclear Information System (INIS)

    Magnesio-thermic Reduction (MTR) trials were started in early sixties in Uranium Metal Plant (UMP) and the first uranium ingot weighing about 8 kg came out in April 1963. The trials were continued and about 20 ingots of 45 kg were produced initially. These trials were conducted in a small shed which was situated at the same place where the present MTR Section is functioning in UMP. As calcium metal was available during that time from abroad without much difficulty, the uranium ingot production was continued using calcium. Later, switching over to magnesio-thermic reduction became essential due to non availability of calcium and for cost reduction

  15. The analysis of uranium prospecting, mining and extraction plant samples

    International Nuclear Information System (INIS)

    The physical methods for the determination of uranium, such as x-ray fluorescence spectrometry, radiometric analysis, fluorimetric analysis, emission spectrographic analysis, and neutron activation analysis, are discussed as well as the chemical methods for the determination of uranium such as decomposition, spectrophotometric methods and the volumetric determination of U3O8 in ammonium diuranate slurries. The general methods of analysis for plant control is discussed, especially regarding the determination of cobalt, manganese, iron, free acids, chlorides, nitrates, silica, amines, isodecanol, thiocyanates and tetrathionates in uranium solvent extraction and leaching processes

  16. Nondestructive analysis at B and W's uranium conversion plant

    International Nuclear Information System (INIS)

    Containers and processing lines bearing high and low enriched uranium are routinely analyzed by nondestructive assay. Measurement systems used at Babcock and Wilcox's nuclear fuels plant in Apollo, Pennsylvania include the segmented gamma scanner (SGS) and the stabilized assay meter (SAM-II). These systems have been calibrated and used for a variety of tasks including uranium holdup measurements prior to decommissioning, in situ filter analysis and assay of calcined waste. 2 refs

  17. Extraction of uranium from seawater: evaluation of uranium resources and plant siting

    International Nuclear Information System (INIS)

    This report deals with the evaluation of U.S. coastal waters as a uranium resource and with the selection of a suitable site for construction of a large-scale plant for uranium extraction. Evaluation of the resource revealed that although the concentration of uranium is quite low, about 3.3 ppB in seawater of average oceanic salinity, the amount present in the total volume of the oceans is very great, some 4.5 billion metric tons. Of this, perhaps only that uranium contained in the upper 100 meters or so of the surface well-mixed layer should be considered accessible for recovery, some 160 million tonnes. The study indicated that open ocean seawater acquired for the purpose of uranium extraction would be a more favorable resource than rivers entering the sea, cooling water of power plants, or the feed or effluent streams of existing plants producing other products such as magnesium, bromine, or potable and/or agricultural water from seawater. Various considerations led to the selection of a site for a pumped seawater coastal plant at a coastal location. Puerto Yabucoa, Puerto Rico was selected. Recommendations are given for further studies. 21 figures, 8 tables

  18. Reprocessed uranium influence on clearance application in uranium fuel fabrication plant

    International Nuclear Information System (INIS)

    Clearance levels for uranium isotopes have been recently authorized in Japan. The measurement of those elements can be disregarded when the nominal of the element (D/C), expressed as (D/C)*, is less than 10-3, where D is the specific radioactivity concentration of nuclides, C is the clearance level of nuclides, and (D/C)* is defined as (D/C) divided by the highest value of (D/C)'s in the element constitutions of uranium waste. In this study, the concentration of nuclides in reprocessed uranium was evaluated using ORIGEN2 burnup analyses and the most appropriate decontamination factors for determining the (D/C)* values and their influence on clearance application in the uranium fuel fabrication plant. It was concluded that nuclides other than five isotopes, 232U, 234U, 235U, 236U, and 238U, can be disregarded with regards to clearance application in the uranium fabrication plant, regardless of operation conditions, whether the fuel is fabricated by receiving reprocessed uranium or not. (author)

  19. Uptake of uranium by aquatic plants growing in fresh water ecosystem around uranium mill tailings pond at Jaduguda, India.

    Science.gov (United States)

    Jha, V N; Tripathi, R M; Sethy, N K; Sahoo, S K

    2016-01-01

    Concentration of uranium was determined in aquatic plants and substrate (sediment or water) of fresh water ecosystem on and around uranium mill tailings pond at Jaduguda, India. Aquatic plant/substrate concentration ratios (CRs) of uranium were estimated for different sites on and around the uranium mill tailings disposal area. These sites include upstream and downstream side of surface water sources carrying the treated tailings effluent, a small pond inside tailings disposal area and residual water of this area. Three types of plant groups were investigated namely algae (filamentous and non-filamentous), other free floating & water submerged and sediment rooted plants. Wide variability in concentration ratio was observed for different groups of plants studied. The filamentous algae uranium concentration was significantly correlated with that of water (r=0.86, p<0.003). For sediment rooted plants significant correlation was found between uranium concentration in plant and the substrate (r=0.88, p<0.001). Both for other free floating species and sediment rooted plants, uranium concentration was significantly correlated with Mn, Fe, and Ni concentration of plants (p<0.01). Filamentous algae, Jussiaea and Pistia owing to their high bioproductivity, biomass, uranium accumulation and concentration ratio can be useful for prospecting phytoremediation of stream carrying treated or untreated uranium mill tailings effluent. PMID:26360459

  20. 77 FR 2718 - CPV Cimarron Renewable Energy Company, LLC; Supplemental Notice That Initial Market-Based Rate...

    Science.gov (United States)

    2012-01-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission CPV Cimarron Renewable Energy Company, LLC; Supplemental Notice That Initial... notice in the above-referenced proceeding of CPV Cimarron Renewable Energy Company, LLC's application...

  1. Uranium uptake by hydroponically cultivated crop plants

    Czech Academy of Sciences Publication Activity Database

    Soudek, Petr; Petrová, Šárka; Benešová, Dagmar; Dvořáková, Marcela; Vaněk, Tomáš

    2011-01-01

    Roč. 102, č. 6 (2011), s. 598-604. ISSN 0265-931X R&D Projects: GA MŠk OC09082; GA MŠk 2B06187; GA MŠk 2B08058 Institutional research plan: CEZ:AV0Z50380511 Keywords : Uranium * Uptake * Sinapis alba Subject RIV: DK - Soil Contamination ; De-contamination incl. Pesticides Impact factor: 1.339, year: 2011

  2. Feedback Experience from Decommissioning of Uranium Conversion Plant

    International Nuclear Information System (INIS)

    KAERI has been conducting decommissioning activities of Uranium Conversion Plant (UCP) for the last decade. As a result of all this work KAERI has accumulated significant experience in the field of decommissioning of nuclear facilities. On the basis of the experience gained from decommissioning activities, this paper describes several lessons learned

  3. Selected bibliography for the extraction of uranium from seawater: evaluation of uranium resources and plant siting

    Energy Technology Data Exchange (ETDEWEB)

    Chen, A.C.T.; Gordon, L.I.; Rodman, M.R.; Binney, S.E.

    1979-02-06

    This bibliography contains 471 references pertaining to the evaluation of U.S. territorial ocean waters as a potential uranium resource and to the selection of a site for a plant designed for the large scale extraction of uranium from seawater. This bibliography was prepared using machine literature retrieval, bibliographic, and work processing systems at Oregon State University. The literature cited is listed by author with indices to the author's countries, geographic areas of study, and to a set of keywords to the subject matter.

  4. Selected bibliography for the extraction of uranium from seawater: evaluation of uranium resources and plant siting

    International Nuclear Information System (INIS)

    This bibliography contains 471 references pertaining to the evaluation of U.S. territorial ocean waters as a potential uranium resource and to the selection of a site for a plant designed for the large scale extraction of uranium from seawater. This bibliography was prepared using machine literature retrieval, bibliographic, and work processing systems at Oregon State University. The literature cited is listed by author with indices to the author's countries, geographic areas of study, and to a set of keywords to the subject matter

  5. Uranium production as byproduct from Yarimca (Turkey) phosphoric acid plant

    International Nuclear Information System (INIS)

    Full text: This paper deals with uranium production from the phosphoric acid products of Yarimca Fertilizer Plant. After examination of the phosphate rocks consumed in this plant and the acid products, solvent extraction tests were conducted to determine the effects of acid concentration, solvent concentration in kerosene, contact time and acid solvent ratio on the recoveries of uranium. 98 percent of total uranium in acid was recovered in the organic phase by applying 5 stage extraction. Following the extraction tests, acidic and basic stripping were applied to organic phase and uranium was precipitated as yellow cake from the stripping solutions. In the stripping tests mainly aqueous and organic phase ratio and the stripping time were investigated using HCl and Na2CO3 as stripping agents. Na2CO3 has provided higher uranium recoveries both at the short time and low ratio of the stripping solution. Yellow cakes were produced containing 13-18.4 percent U3o8 from acidic and 30-46.4 percent U3O8 from basic stripping solutions

  6. Removal of hydrogen fluoride from uranium plant emissions

    International Nuclear Information System (INIS)

    Uranium production technology involves the use of hydrogen fluoride at various stages. It is used in the production of uranium tetrafluoride as well as for the production of fluorine for the conversion of tetrafluoride to hexafluoride in isotopic enrichment plants. The sources of HF pollution in the industry, besides accidental spillages and leakages, are the final off-gases from the UF4 production process or from the hydrogen reduction of hexafluoride (where such process is adopted), venting of tanks and reactors containing HF, safety pressure rupture discs as well as dust collection and ventilation systems

  7. Existing status of uranium refining and conversion plant decommissioning project

    International Nuclear Information System (INIS)

    This technical report shows the situation of the dismantling of the main equipment in the radiation-controlled area of a uranium refining and conversion plant. The dismantling was carried out at the beginning of the uranium refining and conversion plant decommissioning project. We started the dismantling in April 2008 and finished it in 29 September 2011. The dismantled waste and equipment were stored in 200 small drums. All the contaminated devices were sealed and kept in this stage. The radioactivity inventory of the uranium refining and conversion plant did not change in this stage. However, the risk of contamination due to the deterioration of this facility with time became remarkably small. Moreover, we were able to get many information and experience about dismantling. Then, we began decommissioning. We were in a new stage from April 2012. We are going to dismantle or tightly close the fluidization media storage underground tank, the neutralization and precipitation system of a waste fluid with fluorine, and the uranium and ventilation system in about three years from now on. (author)

  8. Biometric approach in selecting plants for phytoaccumulation of uranium.

    Science.gov (United States)

    Stojanović, Mirjana; Pezo, Lato; Lačnjevac, Časlav; Mihajlović, Marija; Petrović, Jelena; Milojković, Jelena; Stanojević, Marija

    2016-01-01

    This paper promotes the biometric classification system of plant cultivars, unique characteristics, in terms of the uranium (U) uptake, primarily in the function of the application for phytoremediation. It is known that the degree of adoption of U depends on the plant species and its morphological and physiological properties, but it is less known what impact have plants cultivars, sorts, and hybrids. Therefore, we investigated the U adoption in four cultivars of three plant species (corn, sunflower and soy bean). "Vegetation experiments were carried out in a plastic-house filled with soil (0.66 mgU) and with tailing (15.3 mgU kg(-1)) from closed uranium mine Gabrovnica-Kalna southeast of Serbia". Principal Component Analysis (PCA), Cluster Analysis (CA) and analysis of variance (ANOVA) were used for assessing the effect of different substrates cultivars, plant species and plant organs (root or shoot) on U uptake. Obtained results showed that a difference in U uptake by three investigated plant species depends not only of the type of substrate types and plant organs but also of their cultivars. Biometrics techniques provide a good opportunity for a better understanding the behavior of plants and obtaining much more useful information from the original data. PMID:26606604

  9. The new French uranium refining plant at Narbonne

    International Nuclear Information System (INIS)

    In 1957 the Commissariat l'Energie Atomique in collaboration with two French industrial firms, the Compagnie de Saint-Gobain and the Societe Potasse et Engrais chimique, undertook the construction of a plant for the production of refined uranium on an industrial scale. This plant, which forms part of the French nuclear equipment programme and which works at a capacity of 1000 tons/year, was put into operation in July 1959. First of all the principles on which this under-taking is based are outlined. This is followed by a more detailed account of the construction, including the improvements brought to the process developed at the C.E.A. plant at le Bouchet when it was carried over to the industrial stage by the uranium branch of the Societe d'Etudes et de Travaux. (author)

  10. Impact of arbuscular mycorrhizal fungi on uranium accumulation by plants

    International Nuclear Information System (INIS)

    Contamination by uranium (U) occurs principally at U mining and processing sites. Uranium can have tremendous environmental consequences, as it is highly toxic to a broad range of organisms and can be dispersed in both terrestrial and aquatic environments. Remediation strategies of U-contaminated soils have included physical and chemical procedures, which may be beneficial, but are costly and can lead to further environmental damage. Phytoremediation has been proposed as a promising alternative, which relies on the capacity of plants and their associated microorganisms to stabilize or extract contaminants from soils. In this paper, we review the role of a group of plant symbiotic fungi, i.e. arbuscular mycorrhizal fungi, which constitute an essential link between the soil and the roots. These fungi participate in U immobilization in soils and within plant roots and they can reduce root-to-shoot translocation of U. However, there is a need to evaluate these observations in terms of their importance for phytostabilization strategies

  11. Impact of arbuscular mycorrhizal fungi on uranium accumulation by plants

    Energy Technology Data Exchange (ETDEWEB)

    Dupre de Boulois, H. [Universite catholique de Louvain, Unite de Microbiologie, Croix du Sud 3, 1348 Louvain-la-Neuve (Belgium); Joner, E.J. [Bioforsk Soil and Environment, Fredrik A. Dahls vei 20, N-1432 As (Norway); Leyval, C. [LIMOS, Nancy University, CNRS, Faculte des Sciences, BP239, 54506 Vandoeuvre-les-Nancy, Cedex (France); Jakobsen, I. [Biosystems Department, Riso National Laboratory, Technical University of Denmark, DK-4000 Roskilde (Denmark); Chen, B.D. [Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); Roos, P. [Radiation Research Department, Riso National Laboratory, Technical University of Denmark, DK-4000 Roskilde (Denmark); Thiry, Y.; Rufyikiri, G. [CEN-SCK, Radiation Protection Research Department, 200 Boeretang, 2400 Mol (Belgium); Delvaux, B. [Universite catholique de Louvain, Unite des Sciences du Sol Croix du Sud 2/10, 1348 Louvain-la-Neuve (Belgium); Declerck, S. [Universite catholique de Louvain, Unite de Microbiologie, Croix du Sud 3, 1348 Louvain-la-Neuve (Belgium)], E-mail: declerck@mbla.ucl.ac.be

    2008-05-15

    Contamination by uranium (U) occurs principally at U mining and processing sites. Uranium can have tremendous environmental consequences, as it is highly toxic to a broad range of organisms and can be dispersed in both terrestrial and aquatic environments. Remediation strategies of U-contaminated soils have included physical and chemical procedures, which may be beneficial, but are costly and can lead to further environmental damage. Phytoremediation has been proposed as a promising alternative, which relies on the capacity of plants and their associated microorganisms to stabilize or extract contaminants from soils. In this paper, we review the role of a group of plant symbiotic fungi, i.e. arbuscular mycorrhizal fungi, which constitute an essential link between the soil and the roots. These fungi participate in U immobilization in soils and within plant roots and they can reduce root-to-shoot translocation of U. However, there is a need to evaluate these observations in terms of their importance for phytostabilization strategies.

  12. Lung cancer among workers at a uranium processing plant

    International Nuclear Information System (INIS)

    This study examined the risk of dying from lung cancer among white males who received radiation to the lung as a result of inhaling uranium dust or the dust of uranium compounds. Cases and controls were chosen from a cohort of workers employed in a uranium processing plant during World War II. Cumulative radiation lung dose among study population members ranged from 0 to 75 rads. Relative risk was found to increase with increasing level of exposure even after controlling for age and smoking status, but only for those who were over the age of 45 when first exposed. A statistically significant excess in risk was found for men in this age group with a cumulative lung dose of 20 rads of more. These data suggest that older age groups may be more susceptible to radiation-induced lung cancer than younger age groups

  13. Perimeter safeguards techniques for uranium-enrichment plants

    International Nuclear Information System (INIS)

    In 1972, a working group of the International Atomic Energy Agency identified a goal to develop and evaluate perimeter safeguards for uranium isotope enrichment plants. As part of the United State's response to that goal, Los Alamos Detection and Verification personnel studied gamma-ray and neutron emissions from uranium hexafluoride. They developed instruments that use the emissions to verify uranium enrichment and to monitor perimeter personnel and shipping portals. Unattended perimeter monitors and hand-held verification instruments were evaluated in field measurements and, when possible, were loaned to enrichment facilities for trials. None of the seven package monitoring techniques that were investigated proved entirely satisfactory for an unattended monitor. They either revealed proprietary information about centrifuge design or were subject to interference by shielding materials that could be present in a package. Further evaluation in a centrifuge facility may help in developing an acceptable attended package monitor. 34 figures, 9 tables

  14. Chronicle on the Malargue uranium plant

    International Nuclear Information System (INIS)

    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)

  15. Environmental consequences of uranium atmospheric releases from fuel cycle facility: II. The atmospheric deposition of uranium and thorium on plants

    International Nuclear Information System (INIS)

    Uranium and thorium isotopes were measured in cypress leaves, wheat grains and lettuce taken in the surroundings of the uranium conversion facility of Malvési (South of France). The comparison of activity levels and activity ratios (namely 238U/232Th and 230Th/232Th) in plants with those in aerosols taken at this site and plants taken far from it shows that aerosols emitted by the nuclear site (uranium releases in the atmosphere by stacks and 230Th-rich particles emitted from artificial ponds collecting radioactive waste mud) accounts for the high activities recorded in the plant samples close to the site. The atmospheric deposition process onto the plants appears to be the dominant process in plant contamination. Dry deposition velocities of airborne uranium and thorium were measured as 4.6 × 10−3 and 5.0 × 10−3 m s−1, respectively. - Highlights: • Uranium and thorium were measured in plants near the uranium conversion facility. • Activity ratios show that emissions account for the high activities recorded in the plants. • The atmospheric deposition process appears to dominate in plant contamination. • Dry deposition velocities of airborne uranium and thorium were determined

  16. Capital and operating costs of irradiated natural uranium reprocessing plants

    International Nuclear Information System (INIS)

    This paper presents first a method of analysing natural uranium reprocessing plants investment costs (method similar to LANG and BACH well known in the fuel oil industry) and their operating costs (analysed according to their economic type). This method helps establishing standard cost structures for these plants, allowing thus comparisons between existing or planned industrial facilities. It also helps evaluating the foreseeable consequences of technical progress. Some results obtained are given, concerning: the investment costs sensitivity to the various technical parameters defining the fuel and their comparison according to the country or the economic area taken into account. Finally, the influence of the plants size on their investment costs is shown. (author)

  17. Exploring the Response of Plants Grown under Uranium Stress

    International Nuclear Information System (INIS)

    Uranium is a natural element which is mainly redistributed in the environment due to human activity, including accidents and spillages. Plants may be useful in cleaning up after incidents, although little is yet known about the relationship between uranium speciation and plant response. We analyzed the impact of different uranium (U) treatments on three plant species namely sunflower, oilseed rape and wheat. Using inductively coupled plasma mass spectrometry elemental analysis, together with a panel of imaging techniques including scanning electron microscopy coupled with energy dispersive spectroscopy, transmission electron microscopy and particle-induced X-ray emission spectroscopy, we have recently shown how chemical speciation greatly influences the accumulation and distribution of U in plants. Uranyl (UO22+ free ion) is the predominant mobile form in soil surface at low pH in absence of ligands. With the aim to characterize the early plant response to U exposure, complete Arabidopsis transcriptome microarray experiments were conducted on plants exposed to 50 μM uranyl nitrate for 2, 6 and 30 h and highlighted a set of 111 genes with modified expression at these three time points. Quantitative real-time RT-PCR experiments confirmed and completed CATMA micro-arrays results allowing the characterization of biological processes perturbed by U. Functional categorization of deregulated genes emphasizes oxidative stress, cell wall biosynthesis and hormone biosynthesis and signaling. We showed that U stress is perceived by plant cells like a phosphate starvation stress since several phosphate deprivation marker genes were deregulated by U and also highlighted perturbation of iron homeostasis by U. Hypotheses are presented to explain how U perturbs the iron uptake and signaling response. These results give preliminary insights into the pathways affected by uranyl uptake, which will be of interest for engineering plants to help clean areas contaminated with U. (authors)

  18. Exploring the Response of Plants Grown under Uranium Stress

    Energy Technology Data Exchange (ETDEWEB)

    Doustaly, Fany; Berthet, Serge; Bourguignon, Jacques [CEA, iRTSV, Laboratoire de Physiologie Cellulaire Vegetale, UMR 5168 CEA-CNRS-INRA-Univ. Grenoble Alpes (France); Combes, Florence; Vandenbrouck, Yves [CEA, iRTSV, Laboratoire de Biologie a Grande Echelle, EDyP, CEA-Grenoble (France); Carriere, Marie [CEA, INAC, LAN, UMR E3 CEA-Universite Joseph Fourier, Grenoble (France); Vavasseur, Alain [CEA, IBEB, LBDP, Saint Paul lez Durance, CEA Cadarache (France)

    2014-07-01

    Uranium is a natural element which is mainly redistributed in the environment due to human activity, including accidents and spillages. Plants may be useful in cleaning up after incidents, although little is yet known about the relationship between uranium speciation and plant response. We analyzed the impact of different uranium (U) treatments on three plant species namely sunflower, oilseed rape and wheat. Using inductively coupled plasma mass spectrometry elemental analysis, together with a panel of imaging techniques including scanning electron microscopy coupled with energy dispersive spectroscopy, transmission electron microscopy and particle-induced X-ray emission spectroscopy, we have recently shown how chemical speciation greatly influences the accumulation and distribution of U in plants. Uranyl (UO{sub 2}{sup 2+} free ion) is the predominant mobile form in soil surface at low pH in absence of ligands. With the aim to characterize the early plant response to U exposure, complete Arabidopsis transcriptome microarray experiments were conducted on plants exposed to 50 μM uranyl nitrate for 2, 6 and 30 h and highlighted a set of 111 genes with modified expression at these three time points. Quantitative real-time RT-PCR experiments confirmed and completed CATMA micro-arrays results allowing the characterization of biological processes perturbed by U. Functional categorization of deregulated genes emphasizes oxidative stress, cell wall biosynthesis and hormone biosynthesis and signaling. We showed that U stress is perceived by plant cells like a phosphate starvation stress since several phosphate deprivation marker genes were deregulated by U and also highlighted perturbation of iron homeostasis by U. Hypotheses are presented to explain how U perturbs the iron uptake and signaling response. These results give preliminary insights into the pathways affected by uranyl uptake, which will be of interest for engineering plants to help clean areas contaminated with

  19. Uptake of uranium and thorium by native and cultivated plants

    International Nuclear Information System (INIS)

    Large part of available literature on biogeochemistry of uranium and thorium refers to the studies performed either in highly contaminated areas or in nutrient solutions that have been artificially 'spiked' with radionuclides. Effects of background levels of natural radioactivity on soil-grown plants have not been studied to the same extent. In this paper, we summarised results of greenhouse and field experiments performed by the author from 2000 to 2006. We examined some of the factors affecting transfer of U and Th from soil to plants, differences in uptake of these radionuclides by different plants, relationships between U and Th in soil and in plants, and temporal variations of U and Th in different plant species. Concentrations of radionuclides (critical point for experimental studies on biogeochemistry of U and Th - rare trace elements in non-contaminated regions) and essential plant nutrients and trace elements were determined by instrumental neutron activation analysis.

  20. Evaluation of bioassay program at uranium fuel fabrication plants

    International Nuclear Information System (INIS)

    Results of a comprehensive study of urinalysis, lung burden and personal air sample measurements for workers at a uranium fuel fabrication plant are presented. Correlations between measurements were found and regression models used to explain the relationship between lung burden, daily intakes and urinary excretions of uranium. Assuming the ICRP lung model, the lung burden histories of ten workers were used to estimate the amounts in each of the long-term compartments of the lung. Estimates of the half lives of each compartment and of the maximum relative contributions to the urine from each compartment are given. These values were then used to predict urinary excretions from the long-term compartments for workers at another fuel fabrication plant. The standard error of estimate compared well with the daily variation in urinary excretion. (author)

  1. Environmental consequences of uranium atmospheric releases from fuel cycle facility: II. The atmospheric deposition of uranium and thorium on plants.

    Science.gov (United States)

    Pourcelot, L; Masson, O; Renaud, P; Cagnat, X; Boulet, B; Cariou, N; De Vismes-Ott, A

    2015-03-01

    Uranium and thorium isotopes were measured in cypress leaves, wheat grains and lettuce taken in the surroundings of the uranium conversion facility of Malvési (South of France). The comparison of activity levels and activity ratios (namely (238)U/(232)Th and (230)Th/(232)Th) in plants with those in aerosols taken at this site and plants taken far from it shows that aerosols emitted by the nuclear site (uranium releases in the atmosphere by stacks and (230)Th-rich particles emitted from artificial ponds collecting radioactive waste mud) accounts for the high activities recorded in the plant samples close to the site. The atmospheric deposition process onto the plants appears to be the dominant process in plant contamination. Dry deposition velocities of airborne uranium and thorium were measured as 4.6 × 10(-3) and 5.0 × 10(-3) m s(-1), respectively. PMID:25500060

  2. Uranium accumulation by aquatic plants from uranium-contaminated water in Central Portugal.

    Science.gov (United States)

    Pratas, João; Favas, Paulo J C; Paulo, Carlos; Rodrigues, Nelson; Prasad, M N V

    2012-03-01

    Several species of plants have developed a tolerance to metal that enables them to survive in metal contaminated and polluted sites. Some of these aquatic plants have been reported to accumulate significant amounts of specific trace elements and are, therefore, useful for phytofiltration. This work focuses the potential of aquatic plants for the phytofiltration of uranium (U) from contaminated water. We observed that Callitriche stagnalis, Lemna minor, and Fontinalis antipyretica, which grow in the uraniferous geochemical province of Central Portugal, have been able to accumulate significant amounts of U. The highest concentration of U was found in Callitriche stagnalis (1948.41 mg/kg DW), Fontinalis antipyretica (234.79 mg/kg DW), and Lemna minor (52.98 mg/kg DW). These results indicate their potential for the phytofiltration of U through constructed treatment wetlands or by introducing these plants into natural water bodies in the uraniferous province of Central Portugal. PMID:22567707

  3. Design of Uranium Isotope Separation Plant by Chemical Exchange

    International Nuclear Information System (INIS)

    The methodology to design a solvent extraction plant for uranium isotope separation by chemical exchange is outlined. This process involves the calculator of the number of stages,the capacity of the plant,the flow rates,and reflux ration in banks of mixer settlers or pulse column used in such a plant. The feed is introduced at the middle of the plant,and the product is withdrawn at one end and the tailings at another. The redox reaction system selected is U(IV)-U(VI) and the equilibrium data of the 40% tri-n-octylamine (TOA) in benzene as the organic phase and 4 M HCI as the aqueous phase are used for the design of the real plant. The resulting analysis for the uranium isotope separation shows that more than 4000 number of stages are required and the reflux ratio is around 700 to produce only 1m3 of product containing 3% of U235 and 0,3% of U235 in the tailings. It is also known that the larger the isotope separation constant the smaller the number of stages needed. The method of design can be used for other systems where the isotope separation constants are more favorable

  4. Radiation protection training at uranium hexafluoride and fuel fabrication plants

    International Nuclear Information System (INIS)

    This report provides general information and references useful for establishing or operating radiation safety training programs in plants that manufacture nuclear fuels, or process uranium compounds that are used in the manufacture of nuclear fuels. In addition to a brief summary of the principles of effective management of radiation safety training, the report also contains an appendix that provides a comprehensive checklist of scientific, safety, and management topics, from which appropriate topics may be selected in preparing training outlines for various job categories or tasks pertaining to the uranium nuclear fuels industry. The report is designed for use by radiation safety training professionals who have the experience to utilize the report to not only select the appropriate topics, but also to tailor the specific details and depth of coverage of each training session to match both employee and management needs of a particular industrial operation. 26 refs., 3 tabs

  5. Uranium

    International Nuclear Information System (INIS)

    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.

  6. Impact of arbuscular mycorrhizal fungi on uranium accumulation by plants.

    Science.gov (United States)

    de Boulois, H Dupré; Joner, E J; Leyval, C; Jakobsen, I; Chen, B D; Roos, P; Thiry, Y; Rufyikiri, G; Delvaux, B; Declerck, S

    2008-05-01

    Contamination by uranium (U) occurs principally at U mining and processing sites. Uranium can have tremendous environmental consequences, as it is highly toxic to a broad range of organisms and can be dispersed in both terrestrial and aquatic environments. Remediation strategies of U-contaminated soils have included physical and chemical procedures, which may be beneficial, but are costly and can lead to further environmental damage. Phytoremediation has been proposed as a promising alternative, which relies on the capacity of plants and their associated microorganisms to stabilize or extract contaminants from soils. In this paper, we review the role of a group of plant symbiotic fungi, i.e. arbuscular mycorrhizal fungi, which constitute an essential link between the soil and the roots. These fungi participate in U immobilization in soils and within plant roots and they can reduce root-to-shoot translocation of U. However, there is a need to evaluate these observations in terms of their importance for phytostabilization strategies. PMID:18069098

  7. Biogeochemistry of uranium in plants associated to phosphatic rocks in the coastal region of Syria

    International Nuclear Information System (INIS)

    Investigation studies in general, demonstrate that background levels of U in plant ash are less than 2 ppm and plant materials which contain more in excess of this amount are indicative either of local uranium mineralization, or the presence of high background levels of uranium in the substrate. Uranium concentrations in different plant parts grown on decomposite phosphate rocks in the mountain coast region of Syria was investigated. Mean uranium concentrations in the soil ranged between 0.44 - 3.91 ppm in the reference area and 22 - 92 ppm in the area of outcrop in phosphate rocks. The results showed that low-order plant forms (Fuaria, Lycopodium, and Pteridium) readily accumulate uranium, whereas high-order forms accumulate uranium in certain parts only. The greatest amount of uranium in flowering parts is concentrated in the plant roots, followed by leaves, twigs and fruits. In addition, results showed that there is a good correlation between uranium in soil and uranium in plant roots. the study demonstrate that Galium Canum could be considered as a good uranium indicator plant for two reason: It was distributed on decomposite phosphate rocks only, and the high concentration of uranium in aerial part similar to the concentration in soil (89.9 ppm). Lagurus Ovatus may be considered as uranium indicator plant, because it was highly dense on the outcrop phosphate rocks, and has a high uranium concentration in its roots (up to 93 ppm) and aerial parts (up to 33 ppm) compared to concentrations in roots and aerial parts in the reference area (10.2 and 0.37 ppm) respectively. (Author)

  8. 2010 Status of Uranium Conversion Plant Decommissioning Project

    International Nuclear Information System (INIS)

    The Uranium Conversion Plant (UCP) was used to manufacture 100 tons of UO2. This paper introduced briefly decommissioning activities in the first half year of 2010. powder for the Wolsong-1 CANDU reactor. The conversion plant has been shut down and minimally maintained for the prevention of a contamination by a deterioration of the equipment. The conversion plant has building area of 2916 m2 and two main conversion processes. ADU (Ammonium Di-Uranate) and AUC (Ammonium Uranyl Carbonate) process are installed in the backside and the front side of the building, respectively. Conversion plant has two lagoons, which is to store all wastes generated from the plant operation. Sludge wastes stored 150m3 and 100m3 in Lagoon 1 and 2, respectively. Main compounds of sludge are ammonium nitrate, sodium nitrate, calcium nitrate, and calcium carbonate. In 2000, the decommissioning of the plant was finally decided upon and a decommissioning program was launched to complete by 2010. In the middle of 2004, decommissioning program obtained the approval of regulatory body and decommissioning activities started. The scope of the project includes the removal of all equipment and the release of the building for re-use. The project is scheduled to be completed at the end of 2010 with a total budget of 10.9 billion This paper introduced briefly decommissioning activities in the first half year of 2010

  9. Seismic vulnerability study of the nation's uranium enrichment plants

    International Nuclear Information System (INIS)

    The US Department of Energy's uranium enrichment production is accomplished with three gaseous diffusion plants located at Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio. The plants were built in the 1940's and 1950's with no seismic design requirements and are located in three different seismic zones. Paducah is in the New Madrid seismic zone (UBC-Zone 3), Oak Ridge is in the Southern Appalachian seismic zone (UBC-Zone 2) and Portsmouth is near the Anna, Ohio seismic zone (UBC-Zone 1). This paper discusses the approach that was used to determine the seismic vulnerability of each of the plants in response to safety and operability analysis studies. Using state-of-the-art seismic evaluation methods, the study showed that the plants are more resistant to seismic excitation than previously thought. However, the study also showed that small seismic excitations could cause any one of the plants to shut down because of weak links in the process systems. It was determined that for about $6 million each, the Oak Ridge and Paducah plants could be upgraded to provide continuity of operation and operational safety at the evaluation basis earthquake levels. At Portsmouth the upgrade costs were determined to be about $1 million, much less than Paducah or Oak Ridge because of process equipment uniqueness

  10. Idaho Chemical Processing Plant and Plutonium-Uranium Extraction Plant phaseout/deactivation study

    International Nuclear Information System (INIS)

    The decision to cease all US Department of Energy (DOE) reprocessing of nuclear fuels was made on April 28, 1992. This study provides insight into and a comparison of the management, technical, compliance, and safety strategies for deactivating the Idaho Chemical Processing Plant (ICPP) at Westinghouse Idaho Nuclear Company (WINCO) and the Westinghouse Hanford Company (WHC) Plutonium-Uranium Extraction (PUREX) Plant. The purpose of this study is to ensure that lessons-learned and future plans are coordinated between the two facilities

  11. Lung Cancer Mortality among Uranium Gaseous Diffusion Plant Workers: A Cohort Study 1952–2004

    OpenAIRE

    LW Figgs

    2013-01-01

    Background: 9%–15% of all lung cancers are attributable to occupational exposures. Reports are disparate regarding elevated lung cancer mortality risk among workers employed at uranium gaseous diffusion plants.Objective: To investigate whether external radiation exposure is associated with lung cancer mortality risk among uranium gaseous diffusion workers.Methods: A cohort of 6820 nuclear industry workers employed from 1952 to 2003 at the Paducah uranium gaseous diffusion plant (PGDP) was ass...

  12. Uranium isotope separation by gaseous diffusion and plant safety

    International Nuclear Information System (INIS)

    This report constitutes a safety guide for operators of uranium isotope separation plants, and includes both aspects of safety and protection. Taking into account the complexity of safety problems raised at design and during operation of plants which require specialized guides, this report mainly considers both the protection of man, the environment and goods, and the principles of occupational safety. It does not claim to be comprehensive, but intends to state the general principles, the particular points related to the characteristics of the basic materials and processes, and to set forth a number of typical solutions suitable for various human and technical environments. It is based on the French experience gained during the last fifteen years

  13. 226Ra bioavailability of plants at urgeirica uranium mill tailings

    International Nuclear Information System (INIS)

    Large amounts of solid wastes (tailings) resulting from the exploitation and treatment of uranium ore at the Urgeirica mine (north of Portugal) have been accumulated in dams (tailing ponds). To reduce the dispersion of natural radionuclides into the environment some dams were revegetated with eucalyptus (Eucalyptus globolus) and pines (Pinus pinea). Besides, some shrubs (Cytisus s.p.) are growing at some of the dams. The objective of this study is to determine the 226Ra bioavailability from uranium mill tailings through the quantification of the total and available fraction of radium in the solid wastes and to estimate its transfer to the plants growing on the tailing piles. Plants and solid waste samples were randomly collected at dams. Activity concentration of 226Ra in plants (aerial part and roots) and solid wastes were measured by gamma spectrometry. The exchangeable fraction of radium in solid wastes was quantified using one single step extraction with 1 mol dm-3 ammonium acetate (pH=7) or 1 mol dm-3 calcium chloride solutions. The results obtained for the 226Ra uptake by plants show that 226Ra concentration ratios for eucalyptus and pines decrease at low 226Ra concentration in the solid wastes and appear relatively constant at higher radium concentrations. For shrubs, the concentration ratios increase at higher 226Ra solid waste concentrations approaching a saturation value. Percentage values of 16.0±8.3 and 12.9±8.9, for the fraction of radium extracted from the solid wastes, using 1 mol dm-3 ammonium acetate or calcium chloride solutions respectively, were obtained. The 226Ra concentration ratios determined on the basis of exchangeable radium are one order of magnitude higher than those based on total radium. It can be concluded that, within the standard error values, more consistent 226Ra concentration ratios were obtained when calculated on the basis of available radium than when total radium was considered, for all the dams. (author)

  14. CRITICALITY CONTROL DURING THE DISMANTLING OF A URANIUM CONVERSION PLANT

    International Nuclear Information System (INIS)

    Within the Commissariat a l'Energie Atomique, in the Cadarache Research Center in southern France, the production at the Enriched Uranium Treatment Workshops started in 1965 and ended in 1995. The dismantling is in progress and will last until 2006. The decommissioning is planned in 2007. Since the authorized enrichment in 235U was 10% in some parts of the plant, and unlimited in others, the equipment and procedures were designed for criticality control during the operating period. Despite the best previous removing of the uranium in the inner parts of the equipment, evaluation of the mass of remaining fissile material by in site gamma spectrometry measurement shows that the safety of the ''clean up'' operations requires specific criticality control procedures, this mass being higher than the safe mass. The chosen method is therefore based on the mapping of fissile material in the contaminated parts of the equipment and on the respect of particular rules set for meeting the criticality control standards through mass control. The process equipment is partitioned in separated campaign, and for each campaign the equipment dismantling is conducted with a precise traceability of the pieces, from the equipment to the drum of waste, and the best final evaluation of the mass of fissile material in the drum. The first results show that the mass of uranium found in the dismantled equipment is less than the previous evaluation, and they enable us to confirm that the criticality was safely controlled during the operations. The mass of fissile material remaining in the equipment can be then carefully calculated, when it is lower than the minimal critical mass, and on the basis of a safety analysis, we will be free of any constraints regarding criticality control, this allowing to make procedures easier, and to speed up the operations

  15. Biogeochemistry of uranium in the soil-plant and water-plant systems in an old uranium mine.

    Science.gov (United States)

    Favas, Paulo J C; Pratas, João; Mitra, Soumita; Sarkar, Santosh Kumar; Venkatachalam, Perumal

    2016-10-15

    The present study highlights the uranium (U) concentrations in water-soil-plant matrices and the efficiency considering a heterogeneous assemblage of terrestrial and aquatic native plant species to act as the biomonitor and phytoremediator for environmental U-contamination in the Sevilha mine (uraniferous region of Beiras, Central Portugal). A total of 53 plant species belonging to 22 families was collected from 24 study sites along with ambient soil and/or water samples. The concentration of U showed wide range of variations in the ambient medium: 7.5 to 557mgkg(-1) for soil and 0.4 to 113μgL(-1) for water. The maximum potential of U accumulation was recorded in roots of the following terrestrial plants: Juncus squarrosus (450mgkg(-1) DW), Carlina corymbosa (181mgkg(-1) DW) and Juncus bufonius (39.9mgkg(-1) DW), followed by the aquatic macrophytes, namely Callitriche stagnalis (55.6mgkg(-1) DW) Lemna minor (53.0mgkg(-1) DW) and Riccia fluitans (50.6mgkg(-1) DW). Accumulation of U in plant tissues exhibited the following decreasing trend: root>leaves>stem>flowers/fruits and this confirms the unique efficiency of roots in accumulating this radionuclide from host soil/sediment (phytostabilization). Overall, the accumulation pattern in the studied aquatic plants (L. minor, R. fluitans, C. stagnalis and Lythrum portula) dominated over most of the terrestrial counterpart. Among terrestrial plants, the higher mean bioconcentration factor (≈1 in roots/rhizomes of C. corymbosa and J. squarrosus) and translocation factor (31 in Andryala integrifolia) were encountered in the representing families Asteraceae and Juncaceae. Hence, these terrestrial plants can be treated as the promising candidates for the development of the phytostabilization or phytoextraction methodologies based on the accumulation, abundance and biomass production. PMID:27314898

  16. Chemical Decontamination of Metallic Waste from Uranium Conversion Plant Dismantling

    International Nuclear Information System (INIS)

    Korea Atomic Energy Research Institute (KAERI) started a decommissioning program of the uranium conversion plant. Pre-work was carried as follows; installation of the access control facility, installation of a changing room and shower room, designation of an emergency exit way and indicating signs, installation of a radiation management facility, preparation of a storage area for tools and equipments, inspection and load test of crane, distribution and packaging of existing waste, and pre-decontamination of the equipment surface and the interior. First, decommissioning work was performed in kiln room, which will be used for temporary radioactive waste storage room. Kiln room housed hydro fluorination rotary kiln for production of uranium tetra-fluoride. The kiln is about 0.8 m in diameter and 5.5 m long. The total dismantled waste was 6,690 kg, 73 % of which was metallic waste and 27 % the others such as cable, asbestos, concrete, secondary waste, etc. And effluent treatment room and filtration room were dismantled for installation of decontamination equipment and lagoon sludge treatment equipment. There were tanks and square mixer in these rooms. The total dismantled waste was 17,250 kg, 67% of which was metallic waste and 33% the others. These dismantled metallic wastes consist of stainless and carbon steel. In this paper, the stainless steel plate and pipe were decontaminated by the chemical decontamination with ultrasonic

  17. Sequoyah Uranium Hexafluoride Plant (Docket No. 40-8027): Final environmental statement

    International Nuclear Information System (INIS)

    The proposed action is the continuation of Source Material License SUB-1010 issued to Kerr-McGee Nuclear Corporation authorizing the operation of a uranium hexafluoride manufacturing facility located in Sequoyah County, Oklahoma, close to the confluence of the Illinois and Arkansas Rivers. The plant produces high purity uranium hexafluoride using uranium concentrates (yellowcake) as the starting material. It is currently designed to produce 5000 tons of uranium per year as uranium hexafluoride and has been in operation since February 1970 without significant environmental incident or discernible offsite effect. The manufacturing process being used includes wet chemical purification to convert yellowcake to pure uranium trioxide followed by dry chemical reduction, hydrofluorination, and fluorination technique to produce uranium hexafluoride. 8 figs, 12 tabs

  18. Accumulation of uranium in plant roots absorbed from aqueous solutions

    International Nuclear Information System (INIS)

    In order to study accumulation mechanisms of uranium (U) in terrestrial plants, uptake experiments for U have been carried out by using Indian mustard (Brassica juncea). This plant is edible and known as a heavy metal accumulator, especially for cadmium (Cd). About 30 rootsstocks of Indian mustard grown hydroponically in laboratory dishes were kept in uranyl (UO22+) nitrate solutions (initially 0.5 mmol/l) at 25degC for 24, 48 and 72 hours (h). The average U concentrations in leaves increased until 48 h up to about 0.6 mg/g and then decreased slightly. Those in roots showed similar trends, but with much higher maximum U concentrations of about 30 mg/g. Backscattered electron images under SEM of the roots showed that U was accumulated on the cell edges. EPMA elemental mapping indicated that phosphorus (P) distribution had a very strong correlation with that of U. The distribution of sulfur (S) appeared to be somewhat different form these U and P distributions. These results suggest that U can be absorbed into plant roots as uranyl (UO22+) and might be fixed at the phospholipid rich cell membranes. This U accumulation mechanism appeared to be different from that for Cd which has a close association with S. (author)

  19. Uranium

    International Nuclear Information System (INIS)

    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

  20. Uranium

    International Nuclear Information System (INIS)

    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

  1. Uranium

    International Nuclear Information System (INIS)

    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

  2. Analysis of mdr1-1Δ mutation of MDR1 gene in the “Cimarron Uruguayo” dog

    Directory of Open Access Journals (Sweden)

    Rosa Gagliardi B.

    2013-08-01

    Full Text Available Objective. The aim of this paper is to analyze the frequency of the mdr1-1D mutation of the MDR1 gene in a dog sample of the Uruguayan Cimarron breed with the objective of increasing the knowledge of this breed’s genome. Materials and methods. Thirty-six animals of this breed were analyzed. The MDR1 gene region, which includes the location where the mutation would be present, was amplified by PCR. Results. The mutation was not detected in any of the analyzed Uruguayan Cimarron. Conclusions. The lack of described ivermectin intoxication cases in veterinary clinic in this breed is explained by the lack of the mutation object of this study. The sequence studied in Cimarron dogs is kept compared to other breeds, except Collies and related breeds (Border Collie, Bearded Collie, Old English sheepdog.

  3. Uranium

    International Nuclear Information System (INIS)

    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.)

  4. Uranium

    International Nuclear Information System (INIS)

    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

  5. Uranium in soil, forest litter and living plant material above three uranium mineralizations in Northern Sweden

    International Nuclear Information System (INIS)

    In order to investigate the feasibility of biogeochemical sampling media in uranium exploration, samples from the most common trees and low bushes together with forest litter were collected over the areas of three uranium mineralizations in Northern Sweden and analyzed for uranium. The results were compared with uranium content of the till and its radioactivity. The average uranium content was low for all sample types and considerably lower in the ash of the organic sample types compared to that of the till. No sample type showed any tendency of having higher uranium concentration above mineralizations compared to background areas. These results suggest that, under conditions prevailing in Sweden, the investigated sample types are not suitable for uranium exploration

  6. Material surveillance and verification program at a uranium enriching plant

    International Nuclear Information System (INIS)

    A license for a nuclear facility in the United States is approved only after a licensee demonstrates by procedure or practice that an adequate material control system exists. A license can specify acceptable material control practices. Therefore, processors in the United States receiving uranium hexafluoride (UF6) from a U. S. Government-owned enriching plant can accept shipper's values for nuclear material accounting purposes if: there is surveillance during withdrawal of the UF6, an independent sample is obtained, and certain measurement verification is subsequently performed by the receiver or the receiver's agent. Because of the high equipment and operating costs, essentially all UF6 processors have adopted a surveillance and verification program. A resident observer is employed to perform surveillance, obtain samples, and tamper-safe the shipping cylinders. Samples are analyzed by the receiver or by an independent laboratory. The observer determines by surveillance that withdrawals, or transfers of material, weighings, and sampling are accomplished in accordance with accepted procedures. Surveillance of the withdrawals includes observing the transfer of UF6 from the enriching plant cylinder to the shipping cylinder(s) and the withdrawal of samples. In addition, it inclu

  7. Role of uranium speciation in the uptake and translocation of uranium by plants

    International Nuclear Information System (INIS)

    Uranium (U) uptake and translocation by plants was characterized using a computer speciation model to develop a nutrient culture system that provided U as a single predominant species in solution. A hydroponic uptake study determined that at pH 5.0, the uranyl (UO22+) cation was more readily taken up and translocated by peas (Pisum sativum) than the hydroxyl and carbonate U complexes present in the solution at pH 6.0 and 8.0, respectively. A subsequent experiment tested the extent to which various monocot and dicot species take up and translocate the uranyl cation. Of the species screened, tepary bean (Phaseolus acutifolius) and red beet (Beta vulgaris) were the species showing the greatest accumulation of U. In addition to providing fundamental information regarding U uptake by plants, the results obtained also have implications for the phytoremediation of U-contaminated soils. The initial characterization of U uptake by peas suggested that in the field, a soil pH of <5.5 would be required in order to provide U in the most plant-available form. A pot study using U-contaminated soil was therefore conducted to assess the extent to which two soil amendments, HEDTA and citric acid, were capable of acidifying the soil, increasing U solubility, and enhancing U uptake by red beet. Of these two amendments, only citric acid proved effective, decreasing the soil pH to 5.0 and increasing U accumulation by a factor of 14. The results of this pot study provide a basis for the development of an effective phytoremediation strategy for U-contaminated soils. (author)

  8. Spectrophotometric determination of uranium in liquid waste generated in Fuel Fabrication Plant

    International Nuclear Information System (INIS)

    During fabrication of uranium bearing nuclear fuels, liquid waste is being generated. The liquid waste contains impurities such as Ca, Na, Fe, Ni, Cr etc. The total dissolved solids (TDS) are high, upto 400 gram per litre (gpl). Study has been carried out for spectrophotometric determination of uranium in solution employing Arsenazo-III as metal indicator. The absorbance was measured at 655 nm. For U: Ca ratio 1:10 no interference was observed. For U:Ca ratio of 1:125, uranium concentration was reduced by ∼5%. The method can be applied for determination of uranium in liquid waste generated in fuel fabrication plant. (author)

  9. Uranium recovery from waste of the nuclear fuel cycle plants at IPEN-CNEN/SP, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Antonio A.; Ferreira, Joao C.; Zini, Josiane; Scapin, Marcos A.; Carvalho, Fatima Maria Sequeira de, E-mail: afreitas@ipen.b, E-mail: jcferrei@ipen.b, E-mail: jzini@ipen.b, E-mail: mascapin@ipen.b, E-mail: fatimamc@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Sodium diuranate (DUS) is a uranium concentrate produced in monazite industry with 80% typical average grade of U{sup 3}O{sup 8}, containing sodium, silicon, phosphorus, thorium and rare earths as main impurities. Purification of such concentrate was achieved at the nuclear fuel cycle pilot plants of uranium at IPEN by nitric dissolution and uranium extraction into an organic phase using TBP/Varsol, while the aqueous phase retains impurities and a small quantity of non extracted uranium; both can be recovered later by precipitation with sodium hydroxide. Then the residual sodium diuranate goes to a long term storage at a safeguards deposit currently reaching 20 tonnes. This work shows how uranium separation and purification from such bulk waste can be achieved by ion exchange chromatography, aiming at decreased volume and cost of storage, minimization of environmental impacts and reduction of occupational doses. Additionally, the resulting purified uranium can be reused in nuclear fuel cycle.(author)

  10. Uranium recovery from waste of the nuclear fuel cycle plants at IPEN-CNEN/SP, Brazil

    International Nuclear Information System (INIS)

    Sodium diuranate (DUS) is a uranium concentrate produced in monazite industry with 80% typical average grade of U3O8, containing sodium, silicon, phosphorus, thorium and rare earths as main impurities. Purification of such concentrate was achieved at the nuclear fuel cycle pilot plants of uranium at IPEN by nitric dissolution and uranium extraction into an organic phase using TBP/Varsol, while the aqueous phase retains impurities and a small quantity of non extracted uranium; both can be recovered later by precipitation with sodium hydroxide. Then the residual sodium diuranate goes to a long term storage at a safeguards deposit currently reaching 20 tonnes. This work shows how uranium separation and purification from such bulk waste can be achieved by ion exchange chromatography, aiming at decreased volume and cost of storage, minimization of environmental impacts and reduction of occupational doses. Additionally, the resulting purified uranium can be reused in nuclear fuel cycle.(author)

  11. Uptake of Uranium and Other Elements of Concern by Plants Growing on Uranium Mill Tailings Disposal Cells

    Science.gov (United States)

    Joseph, C. N.; Waugh, W.; Glenn, E.

    2015-12-01

    The U.S. Department of Energy (DOE) is responsible for long-term stewardship of disposal cells for uranium mill tailings throughout the United States. Rock-armored disposal cell covers create favorable habitat for deep-rooted plants by reducing soil evaporation, increasing soil water storage, and trapping windblown dust, thereby providing water and nutrients for plant germination and establishment. DOE is studying the tradeoffs of potential detrimental and beneficial effects of plants growing on disposal cell covers to develop a rational and consistent vegetation management policy. Plant roots often extend vertically through disposal cell covers into underlying tailings, therefore, uptake of tailings contaminants and dissemination through animals foraging on stems and leaves is a possible exposure pathway. The literature shows that plant uptake of contaminants in uranium mill tailings occurs, but levels can vary widely depending on plant species, tailings and soil chemistry, and cover soil hydrology. Our empirical field study measured concentrations of uranium, radium, thorium, molybdenum, selenium, manganese, lead, and arsenic in above ground tissues harvested from plants growing on disposal cells near Native American communities in western states that represent a range of climates, cover designs, cover soil types, and vegetation types. For risk screening, contaminant levels in above ground tissues harvested from plants on disposal cells were compared to Maximum Tolerance Levels (MTLs) set for livestock by the National Research Council, and to tissue levels in the same plant species growing in reference areas near disposal cells. Although tailings were covered with uncontaminated soils, for 14 of 46 comparisons, levels of uranium and other contaminants were higher in plants growing on disposal cells compared to reference area plants, indicating possible mobilization of these elements from the tailing into plant tissues. However, with one exception, all plant

  12. The behavior of uranium in the soil/plant system with special consideration of the uranium input by mineral phosphorus fertilizer

    International Nuclear Information System (INIS)

    The fate of uranium in the environment and, consequently, its hazard potential for human beings is still discussed controversially in the scientific literature. Mineral phosphorous fertilizer can contain uranium as impurity, so that their application can cause an additional input of uranium into agricultural environments. It is still unclear whether and to what extent fertilizer-derived uranium can enter the human food chain by the consumption of contaminated waters or vegetable crop products. The mobility and availability of uranium in the agricultural ecosystem is mainly determined by its behavior in the pedosphere. Due to interactions with organic and inorganic components, the pedosphere is an effective storage and filter system for pollutants and thus plays an important role for the fate of uranium in the environment. In order to improve the assessment of the hazard potential, the present study investigates the behavior of uranium in the soil/plant-system with a focus on the uranium input by mineral phosphorous fertilizer. The specific objectives were (A) to investigate the general distribution of uranium in soils, (B) to determine the effect of CaCO3 on the sorption behavior of uranium and to quantify the effects of (C - D) varying substrate properties and (E) the application of phosphorus fertilizers on the uranium uptake by ryegrass. The results of these experiments imply that the use of mineral phosphorous fertilizers does not pose an acute risk within the meaning of consumer protection. The studied soils predominantly had a high to very high sorption capability for uranium. At the same time, a small soil-to-plant-transfer of uranium was determined, where the majority of uranium accumulated in/to the plant roots. The availability of uranium in soils and its uptake by plants can thus be classified as generally low. Furthermore, some soil parameters were identified which seem to favor a higher uranium-availability. This study found that very high and very low

  13. Summary of uranium refining and conversion pilot plant at Ningyo-toge works

    International Nuclear Information System (INIS)

    In the Ningyo-toge works, Power Reactor and Nuclear Fuel Development Corp., the construction of the uranium refining and conversion pilot plant was completed, and the operation will be started after the various tests based on the related laws. As for the uranium refining in Japan, the PNC process by wet refining method has been developed since 1958. The history of the development is described. It was decided to construct the refining and conversion pilot plant with 200 t uranium/year capacity as the comprehensive result of the development. This is the amount sufficient to supply UF6 to the uranium enrichment pilot plant in Ningyo-toge. The building for the refining and conversion pilot plant is a three-story ferro-concrete building with the total floor area of about 13,000 m2. The raw materials are the uranium ore produced in Ningyo-toge and the yellow cakes from abroad. Uranyl sulfate solution is obtained by solvent extraction using an extraction tower or a mixer-settler. The following processes are electrolytic reduction, precipitation of uranium tetrafluoride, filtration, drying, dehydration and UF6 conversion. The fluorine for UF6 conversion is produced by the facility in the plant. The operation of the pilot plant will be started in the latter half of the fiscal year 1981, the batch operation is carrried out in 1982, and the continuous operation from 1983. (Kako, I.)

  14. Soil and plant selenium at a reclaimed uranium mine.

    Science.gov (United States)

    Sharmasarkar, Shankar; Vance, George F

    2002-01-01

    Selenium (Se) associated with reclaimed uranium (U) mine lands may result in increased food chain transfer and water contamination. To assess post-reclamation bioavailability of Se at a U mine site in southeastern Wyoming, we studied soil Se distribution, dissolution, speciation, and sorption characteristics and plant Se accumulation. Phosphate-extractable soil Se exceeded the critical limit of 0.5 mg/kg in all the samples, whereas total soil Se ranged from a low (0.6 mg/kg) to an extremely high (26 mg/kg) value. Selenite was the dominant species in phosphate and ammonium bicarbonate-diethylenetriamine pentaacetic acid (AB-DTPA) extracts, whereas selenate was the major Se species in hot water extracts. Extractable soil Se concentrations were in the order of KH2PO4 > AB-DTPA > hot water > saturated paste. The soils were undersaturated with respect to various Se solid phases, albeit with high levels of extractable Se surpassing the critical limit. Calcium and Mg minerals were the potential primary solids controlling Se dissolution, with dissolved organic carbon in the equilibrium solutions resulting in enhanced Se availability. Adsorption was a significant (r2 = 0.76-0.99 at P phytoremediation, or the palatable forage species may be used as animal feed supplements in Se-deficient areas. PMID:12371169

  15. 77 FR 14010 - Rocky Ridge Wind Project, LLC, Blackwell Wind, LLC, CPV Cimarron Renewable Energy Company, LLC...

    Science.gov (United States)

    2012-03-08

    ... Cimarron Renewable Energy Company, LLC, Minco Wind Interconnection Services, LLC, Shiloh III Lessee, LLC, California Ridge Wind Energy LLC, Perrin Ranch Wind, LLC, Erie Wind, LLC: Notice of Effectiveness of Exempt... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY...

  16. 75 FR 16098 - Southern Turner Cimarron I, LLC; Supplemental Notice That Initial Market-Based Rate Filing...

    Science.gov (United States)

    2010-03-31

    ... From the Federal Register Online via the Government Publishing Office ] DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Southern Turner Cimarron I, LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request for Blanket Section 204 Authorization March 24, 2010. This is a supplemental notice in the...

  17. Material surveillance and verification programme at a uranium enriching plant

    International Nuclear Information System (INIS)

    A licence for a nuclear facility in the United States of America is approved only after a licencee demonstrates by procedure or practice that an adequate material control system exists. A licence can specify acceptable material control practices. Therefore, processors in the United States receiving uranium hexafluoride (UF6) from a United States Government-owned enriching plant can accept shipper's values for nuclear material accounting purposes if: (1) there is surveillance during withdrawal of the UF6; (2) an independent sample is obtained; and (3) certain measurement verification is subsequently performed by the receiver or the receiver's agent. Because of the high equipment and operating costs, essentially all UF6 processors have adopted a surveillance and verification programme. A resident observer is employed to perform surveillance, obtain samples, and make the shipping cylinders tamper-safe. Samples are analysed by the receiver or by an independent laboratory. The observer determines by surveillance that withdrawals, or transfers of material, weighings, and sampling are accomplished in accordance with accepted procedures. Surveillance of the withdrawals includes observing the transfer of UF6 from the enriching plant cylinder to the shipping cylinder(s) and the withdrawal of samples. In addition, it includes observing the weighing of all cylinders associated with a sample lot of UF6. Following the surveillance of withdrawals, weighings, and sampling, the cylinders are made tamper-safe by the application of tamper-indicating devices. Statistics for the verification programme have shown shipper and receiver measurements to be within the limits acceptable for adequate material control. (author)

  18. Containment and storage of uranium hexafluoride at US Department of Energy uranium enrichment plants

    International Nuclear Information System (INIS)

    Isotopically depleted UF6 (uranium hexafluoride) accumulates at a rate five to ten times greater than the enriched product and is stored in steel vessels at the enrichment plant sites. There are approximately 55,000 large cylinders now in storage at Paducah, Kentucky; Portsmouth, Ohio; and Oak Ridge, Tennessee. Most of them contain a nominal 14 tons of depleted UF6. Some of these cylinders have been in the unprotected outdoor storage environment for periods approaching 40 years. Storage experience, supplemented by limited corrosion data, suggests a service life of about 70 years under optimum conditions for the 48-in. diameter, 5/16-in.-wall pressure vessels (100 psi working pressure), using a conservative industry-established 1/4-in.-wall thickness as the service limit. In the past few years, however, factors other than atmospheric corrosion have become apparent that adversely affect the serviceability of small numbers of the storage containers and that indicate the need for a managed program to ensure maintenance ofcontainment integrity for all the cylinders in storage. The program includes periodic visual inspections of cylinders and storage yards with documentation for comparison with other inspections, a group of corrosion test programs to permit cylinder life forecasts, and identification of (and scheduling for remedial action) situations in which defects, due to handling damage or accelerated corrosion, can seriously shorten the storage life or compromise the containment integrity of individual cylinders. The program also includes rupture testing to assess the effects of certain classes of damage on overall cylinder strength, aswell as ongoing reviews of specifications, procedures, practices, and inspection results to effect improvements in handling safety, containment integrity, and storage life

  19. Digital data sets that describe aquifer characteristics of the alluvial and terrace deposits along the Cimarron River from Freedom to Guthrie in northwestern Oklahoma

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digital water-level elevation contours for the alluvial and terrace deposits along the Cimarron River in northwestern Oklahoma during...

  20. Digital data sets that describe aquifer characteristics of the alluvial and terrace deposits along the Cimarron River from Freedom to Guthrie in northwestern Oklahoma

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digital aquifer boundaries for the alluvial and terrace deposits along the Cimarron River from Freedom to Guthrie in northwestern...

  1. Digital data sets that describe aquifer characteristics of the alluvial and terrace deposits along the Cimarron River from Freedom to Guthrie in northwestern Oklahoma

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digital polygons of constant hydraulic conductivity values for the alluvial and terrace deposits along the Cimarron River from Freedom to...

  2. Digital data sets that describe aquifer characteristics of the alluvial and terrace deposits along the Cimarron River from Freedom to Guthrie in northwestern Oklahoma

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set consists of digital polygons of a constant recharge rate for the alluvial and terrace deposits along the Cimarron River from Freedom to Guthrie in...

  3. Melting characteristics of the stainless steel generated from the uranium conversion plant

    International Nuclear Information System (INIS)

    The partition ratio of cerium (Ce) and uranium (U) in the ingot, slag and dust phases has been investigated for the effect of the slag type, slag concentration and basicity in an electric arc melting process. An electric arc furnace (EAF) was used to melt the stainless steel wastes, simulated by uranium oxide and the real wastes from the uranium conversion plant in Korea Atomic Energy Research Institute (KAERI). The composition of the slag former used to capture the contaminants such as uranium, cerium, and cesium during the melt decontamination process generally consisted of silica (SiO2), calcium oxide (CaO) and aluminum oxide (Al2O3). Also, Calcium fluoride (CaF2 ), nickel oxide (NiO), and ferric oxide (Fe2O3) were added to provide an increase in the slag fluidity and oxidative potential. Cerium was used as a surrogate for the uranium because the thermochemical and physical properties of cerium are very similar to those of uranium. Cerium was removed from the ingot phase to slag phase by up to 99% in this study. The absorption ratio of cerium was increased with an increase of the amount of the slag former. And the maximum removal of cerium occurred when the basicity index of the slag former was 0.82. The natural uranium (UO2) was partitioned from the ingot phase to the slag phase by up to 95%. The absorption of the natural uranium was considerably dependent on the basicity index of the slag former and the composition of the slag former. The optimum condition for the removal of the uranium was about 1.5 for the basicity index and 15 wt% of the slag former. According to the increase of the amount of slag former, the absorption of uranium oxide in the slag phase was linearly increased due to an increase of its capacity to capture uranium oxide within the slag phase. Through experiments with various slag formers, we verified that the slag formers containing calcium fluoride (CaF2) and a high amount of silica were more effective for a melt decontamination of

  4. Environmental report of Purex Plant and Uranium Oxide Plant - Hanford reservation

    International Nuclear Information System (INIS)

    A description of the site, program, and facilities is given. The data and calculations indicate that there will be no significant adverse environmental impact from the resumption of full-scale operations of the Purex and Uranium Oxide Plants. All significant pathways of radionuclides in Purex Plant effluents are evaluated. This includes submersion in the airborne effluent plumes, consumption of drinking water and foodstuffs irrigated with Columbia River water, ingestion of radioactive iodine through the cow-to-milk pathway, consumption of fish, and other less significant pathways. A summary of research and surveillance programs designed to assess the possible changes in the terresstrial and aquatic environments on or near the Hanford Reservation is presented. The nonradiological discharges to the environment of prinicpal interest are chemicals, sewage, and solid waste. These discharges will not lead to any significant adverse effects on the environment

  5. Criteria for the safe storage of enriched uranium at the Y-12 Plant

    Energy Technology Data Exchange (ETDEWEB)

    Cox, S.O.

    1995-07-01

    Uranium storage practices at US Department of Energy (DOE) facilities have evolved over a period spanning five decades of programmatic work in support of the nuclear deterrent mission. During this period, the Y-12 Plant in Oak Ridge, Tennessee has served as the principal enriched uranium facility for fabrication, chemical processing, metallurgical processing and storage. Recent curtailment of new nuclear weapons production and stockpile reduction has created significant amounts of enriched uranium available as a strategic resource which must be properly and safely stored. This standard specifies criteria associated with the safe storage of enriched uranium at the Y-12 Plant. Because programmatic needs, compliance regulations and desirable materials of construction change with time, it is recommended that these standards be reviewed and amended periodically to ensure that they continue to serve their intended purpose.

  6. Uranium transfer in the food chain from soil to plants, animals and man

    International Nuclear Information System (INIS)

    Our investigations aimed at following up the scientific basis of uranium transfer from the soils of different geological origins and from the immediate vicinity of uranium waste dumps in the vegetation, in waters (drinking water, mineral water and medicinal water), vegetable and animal foodstuffs and beverages; the regional human uranium intake, excretion, apparent absorption and balance in Germany and Mexico. Another aim of the investigations was to draw conclusions from the rules of transfer of this element from the rocks and soils to plants, animals and man. (authors)

  7. Selected bibliography for the extraction of uranium from seawater: chemical process and plant design feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Binney, S.E.; Polkinghorne, S.T.; Jante, R.R.; Rodman, M.R.; Chen, A.C.T.; Gordon, L.I.

    1979-02-01

    A selected annotated bibliography of 521 references was prepared as a part of a feasibility study of the extraction of uranium from seawater. For the most part, these references are related to the chemical processes whereby the uranium is removed from the seawater. A companion docment contains a similar bibliography of 471 references related to oceanographic and uranium extraction plant siting considerations, although some of the references are in common. The bibliography was prepared by computer retrieval from Chemical Abstracts, Nuclear Science Abstracts, Energy Data Base, NTIS, and Oceanic Abstracts. References are listed by author, country of author, and selected keywords.

  8. Selected bibliography for the extraction of uranium from seawater: chemical process and plant design feasibility study

    International Nuclear Information System (INIS)

    A selected annotated bibliography of 521 references was prepared as a part of a feasibility study of the extraction of uranium from seawater. For the most part, these references are related to the chemical processes whereby the uranium is removed from the seawater. A companion docment contains a similar bibliography of 471 references related to oceanographic and uranium extraction plant siting considerations, although some of the references are in common. The bibliography was prepared by computer retrieval from Chemical Abstracts, Nuclear Science Abstracts, Energy Data Base, NTIS, and Oceanic Abstracts. References are listed by author, country of author, and selected keywords

  9. Position paper Oak Ridge Y-12 Plant storage of uranium in plastics

    International Nuclear Information System (INIS)

    As a result of the end of the Cold War, the United States nuclear weapon stockpile is being reduced from approximately 20,000 warheads to fewer than 10,000 by the end of the century. The Oak Ridge Y-12 Plant is the Department of Energy (DOE) site charged with the responsibility of providing safe, secure storage for the uranium recovered from these weapons. In addition to weapons material, Y-12 has traditionally processed and stored uranium from nonweapon programs and presumably will continue to do so. The purpose of this document is to evaluate the suitability of plastics for use in the containment of uranium

  10. Assessing depleted uranium (DU) contamination of soil, plants and earthworms at UK weapons testing sites

    OpenAIRE

    Oliver, I.W.; Graham, M C; Mackenzie, A. B.; Ellam, R.M.; Farmer, J.G.

    2007-01-01

    Depleted uranium (DU) weapons testing programmes have been conducted at two locations within the UK. An investigation was therefore carried out to assess the extent of any environmental contamination arising from these test programmes using both alpha spectrometry and mass spectrometry techniques. Uranium isotopic signatures indicative of DU contamination were observed in soil, plant and earthworm samples collected in the immediate vicinity of test firing points and targets, but contamination...

  11. Uranium

    International Nuclear Information System (INIS)

    Canada produced one-third of the Western World's uranium production in 1989, twice as much from Saskatchewan as from Ontario, where mine closures have led to the loss of over 2,000 jobs. Canadian production in 1990 was about 8.8 Gg U. In 1990, Canada's primary producers were Denison Mines, Rio Algom, Cluff Mining, and Cameco. In Saskatchewan, there are three operations: Key Lake, Rabbit Lake/Collins Bay, and Cluff Lake. Canada stands fourth in uranium resources, but because of favourable geology remains the focus of much exploration activity, which cost about C$60 in 1989. Large stockpiles overhang the market, so new sources of uranium will not be needed before the mid 1990's, but long-term prospects seem good

  12. Uranium

    International Nuclear Information System (INIS)

    The uranium production industry is well into its third recession during the nuclear era (since 1945). Exploration is drastically curtailed, and many staffs are being reduced. Historical market price production trends are discussed. A total of 3.07 million acres of land was acquired for exploration; drastic decrease. Surface drilling footage was reduced sharply; an estimated 250 drill rigs were used by the uranium industry during 1980. Land acquisition costs increased 8%. The domestic reserve changes are detailed by cause: exploration, re-evaluation, or production. Two significant discoveries of deposits were made in Mohave County, Arizona. Uranium production during 1980 was 21,850 short tons U3O8; an increase of 17% from 1979. Domestic and foreign exploration highlights were given. Major producing areas for the US are San Juan basin, Wyoming basins, Texas coastal plain, Paradox basin, northeastern Washington, Henry Mountains, Utah, central Colorado, and the McDermitt caldera in Nevada and Oregon. 3 figures, 8 tables

  13. Preliminary studies of the genetic structure of “Cimarron uruguayo” dog using microsatellite markers

    Directory of Open Access Journals (Sweden)

    Rosa Gagliardi B.

    2010-12-01

    Full Text Available Objetive. To analyze the population structure, using microsatellite markers in a sample of “Cimarron Uruguayo” dogs. Materials and methods. Thirty dogs were analyzed in different areas of Uruguay with a set of nine molecular microsatellite markers using PCR. The population structure was analyzed using the free distribution software “Structure’’. Results. According to our data, the preliminary results show that it is not possible to establish a subdivision among the animals in the sample. Conclusions. The study supports the hypothesis that the currently existing canines derive from a founding nucleus that took refuge in the Northeastern region of the country. The distribution of the breed among the different areas of Uruguay continues nowadays, so there is no isolation among the different groups of animals, and the exchange is constant

  14. Guidebook on design, construction and operation of pilot plants for uranium ore processing

    International Nuclear Information System (INIS)

    The design, construction and operation of a pilot plant are often important stages in the development of a project for the production of uranium concentrates. Since building and operating a pilot plant is very costly and may not always be required, it is important that such a plant be built only after several prerequisites have been met. The main purpose of this guidebook is to discuss the objectives of a pilot plant and its proper role in the overall project. Given the wide range of conditions under which a pilot plant may be designed and operated, it is not possible to provide specific details. Instead, this book discusses the rationale for a pilot plant and provides guidelines with suggested solutions for a variety of problems that may be encountered. This guidebook is part of a series of Technical Reports on uranium ore processing being prepared by the IAEA's Division of Nuclear Fuel Cycle and Waste Management. 42 refs, 7 figs, 3 tabs

  15. Internal exposure to uranium in a pooled cohort of gaseous diffusion plant workers

    International Nuclear Information System (INIS)

    Intakes and absorbed organ doses were estimated for 29 303 workers employed at three former US gaseous diffusion plants as part of a study of cause-specific mortality and cancer incidence in uranium enrichment workers. Uranium urinalysis data (>600 000 urine samples) were available for 58 % of the pooled cohort. Facility records provided uranium gravimetric and radioactivity concentration data and allowed estimation of enrichment levels of uranium to which workers may have been exposed. Urine data were generally recorded with facility department numbers, which were also available in study subjects' work histories. Bioassay data were imputed for study subjects with no recorded sample results (33 % of pooled cohort) by assigning department average urine uranium concentration. Gravimetric data were converted to 24-h uranium activity excretion using department average specific activities. Intakes and organ doses were calculated assuming chronic exposure by inhalation to a 5-μm activity median aerodynamic diameter aerosol of soluble uranium. Median intakes varied between 0.31 and 0.74 Bq d-1 for the three facilities. Median organ doses for the three facilities varied between 0.019 and 0.051, 0.68 and 1.8, 0.078 and 0.22, 0.28 and 0.74, and 0.094 and 0.25 mGy for lung, bone surface, red bone marrow, kidneys, and liver, respectively. Estimated intakes and organ doses for study subjects with imputed bioassay data were similar in magnitude. (authors)

  16. A plant taxonomic survey of the Uranium City region, Lake Athabasca north shore, emphasizing the naturally colonizing plants on uranium mine and mill wastes and other human-disturbed sites

    International Nuclear Information System (INIS)

    A goal of this study was to acquire more complete baseline data on the existing flora of the Uranium City region, both in natural and human-disturbed sites. Emphasis was given to determining which plant species were naturally revegetating various abandoned uranium mine and mill waste disposal areas, other human-disturbed sites, and ecologically analogous sites. Another goal was to document the occurrence and distribution in the study region of rare and possibly endangered species. A further objective was to suggest regionally-occurring species with potential value for revegetating uranium mine and mill waste sites. Field investigations were carried out in the Uranium City region during August, 1981. During this time 1412 plant collections were made; a total of 366 plant species - trees, shrubs, forbs, graminoids, lichens, and bryophytes were recorded. The report includes an annotated checklist of plant species of the Uranium City region and a reference index of plant taxa indicating species that have high revegetation potential

  17. Experience with a uranyl nitrate/uranium dioxide conversion pilot plant

    International Nuclear Information System (INIS)

    A plant for the precipitation of sinterable nuclear grade UO2 powders is described in this report. The plant has been designed, built and set up by SNIA TECHINT. ENEA has been involved in the job as nuclear consultant. Main process steps are: dissolution of UO2 powder or sintered UO2 pellets, adjustment of uranyl nitrate solutions, precipitation of uranium peroxide by means of hydrogen peroxide, centrifugation of the precipitate, drying, calcination and reduction to uranium dioxide. The report is divided in two main section: the process description and the ''hot test'' report. Some laboratory data on precipitation of ammonium diuranate by means of NH4OH, are also reported

  18. Radioactivity of waste materials produced from the Inchass uranium extraction pilot plant

    International Nuclear Information System (INIS)

    A pilot plant was constructed at Inchass, Cairo for uranium processing from conventional ore materials consists of 4 rubber lined leaching tanks fitted with the required impellers beside having procured two columns ion-exchange unit from Permutite Company LTD of London and a mixer settler from Henkel USA. The capacity of this unit is 100 kg yellowcake per year. The aim of this work is to study the radioactivity of wastes produced from the pilot plant. Uranium ore, dust, airborne material, solid waste (tailings) and liquid effluents have been collected and analyzed by gamma spectrometry

  19. Characteristics of lagoon sludge waste generated from an uranium conversion plant

    International Nuclear Information System (INIS)

    The Korea Atomic Energy Research Institute (KAERI) has launched a decommissioning program of the uranium conversion plant. The sludge waste, which was generated during the operation of the plant and stored in the lagoon, was characterized for the development of the treatment process. The physical properties were measured and chemical compositions and radiological properties analyzed. The main compounds of the sludge were ammonium nitrate, sodium nitrate, calcium nitrate, and calcium carbonate. All heavy radioactive elements such as uranium, thorium and 226Ra were precipitated and deposited at the bottom, and were not dissolved in the concentrated nitrate solution. A possible flow-scheme for processing is presented. (author)

  20. Root uptake of uranium by a higher plant model (Phaseolus vulgaris) bioavailability from soil solution

    Energy Technology Data Exchange (ETDEWEB)

    Laroche, L.; Henner, P.; Camilleri, V.; Garnier-Laplace, J. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

    2004-07-01

    Uranium behaviour in soils is controlled by actions and interactions between physicochemical and biological processes that also determine its bioavailability. In soil solution, uranium(+VI) aqueous speciation undergoes tremendous changes mainly depending on pH, carbonates, phosphates and organic matter. In a first approach to identify bioavailable species of U to plants, cultures were performed using hydroponics, to allow an easy control of the composition of the exposure media. The latter, here an artificial soil solution, was designed to control the uranium species in solution. The geochemical speciation code JCHESS using a database compiled from the OECD/NEA thermochemical database project and verified was used to perform the solution speciation calculations. On this theoretical basis, three domains were defined for short-duration well-defined laboratory experiments in simplified conditions: pH 4.9, 5.8 and 7 where predicted dominant species are uranyl ions, hydroxyl complexes and carbonates respectively. For these domains, biokinetics and characterization of transmembrane transport according to a classical Michaelis Menten approach were investigated. The Free Ion Model (or its derived Biotic Ligand Model) was tested to determine if U uptake is governed by the free uranyl species or if other metal complexes can be assimilated. The effect of different variables on root assimilation efficiency and phyto-toxicity was explored: presence of ligands such as phosphates or carbonates and competitive ions such as Ca{sup 2+} at the 3 pH. According to previous experiments, uranium was principally located in roots whatever the pH and no difference in uranium uptake was evidenced between the main growth stages of the plant. Within the 3 studied chemical domains, results from short-term kinetics evidenced a linear correlation between total uranium concentration in bean roots and that in exposure media, suggesting that total uranium in soil solution could be a good predictor

  1. 226Ra and 210Pb relationship in solid wastes and plants at Uranium mill tailing

    International Nuclear Information System (INIS)

    After the uranium extraction from the ore, the waste residues (tailings) contain several radionuclides in elevated levels comparing to normal soils. Nearly all of the uranium progenies (230Th, 226Ra, 210Pb and 210Po) and the unextracted uranium fraction are present in tailings. These large quantities of tailings may provide a significant source of environmental and food chain contamination. The transfer of radioisotopes between different ecological compartments is frequently evaluated using ratios which relate the radionuclide content in one ecosystem compartment to that of another. For instance, the concentration ratio (CR), i.e., the ratio between radionuclide concentrations in tailings and plants can be evaluated. Radium-226, a long-lived alfa emitter, is a chemical analog of calcium. The 226Ra uptake is similar to calcium in biological and ecological systems. The uptake of 210Pb will follow the same pattern as natural lead. Plants do not require lead but in contrast they require the Ra/Ca group elements. The uptake of lead is mainly a function of the lead tolerance of the plant and the hydrogen ion concentration of the soil. Kalin and Sharma (1982) reported that 226Ra and 210Pb uptake by indigenous species from inactive uranium mill tailings in Canada differ from the uptake of the elements by the same plants growing in soil. Ibrahim and Whicker (1992) reported that tailing acidity tends to enhance radionuclide availability for plant uptake. The transport of radionuclides to foliage and subsequent retention and absorption may play a role in plant contamination. The main goal of this study is to evaluate the 226Ra and 210Pb relationship in tailings and plants growing at uranium mill tailings

  2. Linearity assumption in soil-to-plant transfer factors of natural uranium and radium in Helianthus annuus L

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, P. Blanco [Departamento de Fisica, Facultad de Ciencias, Universidad de Extremadura, 06071 Badajoz (Spain); Tome, F. Vera [Departamento de Fisica, Facultad de Ciencias, Universidad de Extremadura, 06071 Badajoz (Spain)]. E-mail: fvt@unex.es; Fernandez, M. Perez [Area de Ecologia, Departamento de Fisica, Facultad de Ciencias, Universidad de Extremadura, 06071 Badajoz (Spain); Lozano, J.C. [Laboratorio de Radiactividad Ambiental, Facultad de Ciencias, Universidad de Salamanca, 37008 Salamanca (Spain)

    2006-05-15

    The linearity assumption of the validation of soil-to-plant transfer factors of natural uranium and {sup 226}Ra was tested using Helianthus annuus L. (sunflower) grown in a hydroponic medium. Transfer of natural uranium and {sup 226}Ra was tested in both the aerial fraction of plants and in the overall seedlings (roots and shoots). The results show that the linearity assumption can be considered valid in the hydroponic growth of sunflowers for the radionuclides studied. The ability of sunflowers to translocate uranium and {sup 226}Ra was also investigated, as well as the feasibility of using sunflower plants to remove uranium and radium from contaminated water, and by extension, their potential for phytoextraction. In this sense, the removal percentages obtained for natural uranium and {sup 226}Ra were 24% and 42%, respectively. Practically all the uranium is accumulated in the roots. However, 86% of the {sup 226}Ra activity concentration in roots was translocated to the aerial part.

  3. Linearity assumption in soil-to-plant transfer factors of natural uranium and radium in Helianthus annuus L

    International Nuclear Information System (INIS)

    The linearity assumption of the validation of soil-to-plant transfer factors of natural uranium and 226Ra was tested using Helianthus annuus L. (sunflower) grown in a hydroponic medium. Transfer of natural uranium and 226Ra was tested in both the aerial fraction of plants and in the overall seedlings (roots and shoots). The results show that the linearity assumption can be considered valid in the hydroponic growth of sunflowers for the radionuclides studied. The ability of sunflowers to translocate uranium and 226Ra was also investigated, as well as the feasibility of using sunflower plants to remove uranium and radium from contaminated water, and by extension, their potential for phytoextraction. In this sense, the removal percentages obtained for natural uranium and 226Ra were 24% and 42%, respectively. Practically all the uranium is accumulated in the roots. However, 86% of the 226Ra activity concentration in roots was translocated to the aerial part

  4. Health physics system scheme for the uranium purification plant

    International Nuclear Information System (INIS)

    After describing the two uranium purification processes used in the Chemical Engineerring Division of the Instituto de Energia Atomica, it is examined the possible hazards and methods to control or eliminate them. Since these purification process present several stages, in each one of them it is evaluated the hazards and tried to give adequate solutions to protect both, personnel and installations, from the potential radiation hazards

  5. Study of uranium and 226Ra uptake by higher plants

    Czech Academy of Sciences Publication Activity Database

    Soudek, Petr; Valenová, Šárka; Benešová, D.; Vaněk, Tomáš

    Santiago de Compostela : Universidade de Santiago de Compostela, 2006, s. 33. [Scientific Meeting of WG1 /1./ Root to shoot translocation of pollutants and nutrients. COST Action /859./. Santiago de Compostela (ES), 22.06.2006-24.06.2006] R&D Projects: GA MŠk(CZ) 1P05OC042 Institutional research plan: CEZ:AV0Z40550506 Keywords : 226radium * phytoremediation * uranium Subject RIV: DK - Soil Contamination ; De-contamination incl. Pesticides

  6. The in-plant evaluation of a uranium NDA system

    Energy Technology Data Exchange (ETDEWEB)

    Sprinkle, J.K. Jr.; Baxman, H.R.; Langner, D.G.; Canada, T.R.; Sampson, T.E.

    1979-01-01

    The Los Alamos Scientific Laboratory has an unirradiated enriched uranium reprocessing facility. Various types of solutions are generated in this facility, including distillates and raffinates containing ppm of uranium and concentrated solutions with up to 400 grams U/t. In addition to uranyl nitrate and HNO{sub 3}, the solutions may also contain zirconium, niobium, fluoride, and small amounts of many metals. A uranium solution assay system (USAS) has been installed to allow accurate and more timely process control, accountability, and criticality data to be obtained. The USAS assays are made by a variety of techniques that depend upon state-of-the-art high-resolution Ge(Li) gamma-ray spectroscopy integrated with an interactive, user-oriented computer software package. Tight control of the system's performance is maintained by constantly monitoring the USAS status. Daily measurement control sequences are required, and the user is forced by the software to perform these sequences. Routine assays require 400 or 1000 seconds for a precision of 0.5% over the concentration range of 5--400 g/t. A comparison of the USAS precision and accuracy with that obtained by traditional destructive analytical chemistry techniques (colorimetric and volumetric) is presented.

  7. Lessons Learned from the Remediation at Villa Aldama Uranium Extraction Plant

    International Nuclear Information System (INIS)

    From 1969 to 1971, a uranium extraction plant operated in close proximity to Villa Aldama city in Chihuahua state; the plant ceased operations in 1971 leaving 30 000 t of uranium tailings, 1735 t of uranium ore and contaminated equipment and buildings. The whole facility and the radioactive material remained almost unattended for more than 20 years. During this time the tailings and ore contaminated the soil around them. At the same time, the city of Villa Aldama expanded and its houses began to approach the site boundary. Because of this and other factors, such as the potential contamination of groundwater, remediation actions were required by the Nuclear Safety and Safeguards National Commission. These actions were, basically, the decontamination of the site and the disposal of the radioactive waste generated in the process. This paper describes the remediation efforts that brought the facility to a safe status. (author)

  8. The creation of a uranium oxide industry, from the laboratory stage to a pilot plant (1961)

    International Nuclear Information System (INIS)

    The qualities of uranium oxide, in particular its good in-pile characteristics and its resistance to corrosion by the usual heat-exchange fluids, have led to this material being chose at the present time as a nuclear fuel in many power reactors, either planned or under construction. A great effort has been made these last few years in France in studying processes for transforming powdered uranium oxide into a dense material with satisfactory behaviour in a neutron flux. The laboratories at Saclay have studied the physico-chemical features of the phenomena accompanying the calcination of uranium peroxide or ammonium uranate to give uranium trioxide, and the subsequent reduction of the latter to dioxide as well as the sintering of the powders obtained. This work has made it possible on one hand to prepare powder of known specific surface area, and on the other to show the overriding influence of this factor, all other things being equal, on the behaviour of powders during sintering in a hydrogen atmosphere. The work has led to defining two methods for sintering stoichiometric uranium oxide of high density. The technological study of the preparation of the powder and its industrial production are carried out at the plant of Le Bouchet which produces at the moment powders of known characteristics suitable for sintering in hydrogen at 1650 deg. C without prior grinding. The industrial sintering is carried out by the Compagnie industrielle des Combustibles Atomiques Frittes who has set up a pilot plant having a capacity of 25 metric tons/year, for the Commissariat l'Energie Atomique and has been operating this plant since May 1958. This plant is presented by a film entitled 'uranium oxide'. (author)

  9. Uranium and radium in water samples around the Nikola Tesla B lignite-fired power plant - Obrenovac, Serbia

    Directory of Open Access Journals (Sweden)

    Žunić Zora S.

    2011-01-01

    Full Text Available This paper deals with the analysis of natural radionuclide content in 23 water samples collected in the vicinity of the Nikola Tesla B thermal power plant, Serbia. All samples were analyzed for 226Ra and uranium isotopes (238U, 234U activity using radiochemical methods and alpha spectrometry. Obtained results show that the activity concentrations for uranium and radium in the water around the thermal power plant are low when compared to those from areas across Serbia with their enhanced natural uranium and radium content. No important radiological hazard related to uranium and radium activity stored in heap was found.

  10. Uranium and radium in water samples around the Nikola Tesla B lignite-fired power plant - Obrenovac, Serbia

    International Nuclear Information System (INIS)

    This paper deals with the analysis of natural radionuclide content in 23 water samples collected in the vicinity of the Nikola Tesla B thermal power plant, Serbia. All samples were analyzed for 226Ra and uranium isotopes (238U, 234U) activity using radiochemical methods and alpha spectrometry. Obtained results show that the activity concentrations for uranium and radium in the water around the thermal power plant are low when compared to those from areas across Serbia with their enhanced natural uranium and radium content. No important radiological hazard related to uranium and radium activity stored in heap was found. (author)

  11. Bioaccumulation of 226Ra in the plants growing near uranium facilities

    Czech Academy of Sciences Publication Activity Database

    Tykva, Richard; Podracká, Eva

    2005-01-01

    Roč. 50, - (2005), S25-S27. ISSN 0029-5922 Institutional research plan: CEZ:AV0Z40550506 Keywords : uranium mine * contaminated soils * plant accumulation Subject RIV: DL - Nuclear Waste, Radioactive Pollution ; Quality Impact factor: 0.289, year: 2005

  12. Standard model for safety analysis report of hexafluoride power plants from natural uranium

    International Nuclear Information System (INIS)

    The standard model for safety analysis report for hexafluoride production power plants from natural uranium is presented, showing the presentation form, the nature and the degree of detail, of the minimal information required by the Brazilian Nuclear Energy Commission - CNEN. (E.G.)

  13. Surface Decontamination of System Components in Uranium Conversion Plant at KAERI

    International Nuclear Information System (INIS)

    A chemical decontamination process using nitric acid solution was selected as in-situ technology for recycle or release with authorization of a large amount of metallic waste including process system components such as tanks, piping, etc., which is generated by dismantling a retired uranium conversion plant at Korea Atomic Energy Research Institute (KAERI). The applicability of nitric acid solution for surface decontamination of metallic wastes contaminated with uranium compounds was evaluated through the basic research on the dissolution of UO2 and ammonium uranyl carbonate (AUC) powder. Decontamination performance was verified by using the specimens contaminated with such uranium compounds as UO2 and AUC taken from the uranium conversion plant. Dissolution rate of UO2 powder is notably enhanced by the addition of H2O2 as an oxidant even in the condition of a low concentration of nitric acid and low temperature compared with those in a nitric acid solution without H2O2. AUC powders dissolve easily in nitric acid solutions until the solution pH attains about 2.5 ∼ 3. Above that solution pH, however, the uranium concentration in the solution is lowered drastically by precipitation as a form of U3(NH3)4O9 . 5H2O. Decontamination performance tests for the specimens contaminated with UO2 and AUC were quite successful with the application of decontamination conditions obtained through the basic studies on the dissolution of UO2 and AUC powders

  14. Process for cleaning adhering or dust deposits in plants for handling uranium hexafluoride

    International Nuclear Information System (INIS)

    Deposits are removed by the reaction with iodine heptafluoride, where trifluor bromium methane or difluor bromium methane is also added. Bromium trifluoride is formed in the plant, which converts uranyl fluoride into uranium hexafluoride. The bromium produced is immediately fluorized by excess iodine hepta fluoride or fluorine. The corrosion effect of the bromine is prevented in this way. The bromium trifluoride is present in liquid form and can completely wet the plant walls. (PW)

  15. The evaluation, design and construction of the uranium plant for Chemwes Limited

    International Nuclear Information System (INIS)

    The Chemwes uranium plant was designed and constructed within fifteen months; commissioning started during June 1979, and the plant was producing at design capacity four months later. This account highlights the procedures and methods adopted to bring the plant into production. The description of the various phases includes some details of the early evaluation, and the feasibility and optimization studies; of the financing, project management, design, construction, and commissioning of the plant; and of the training of personnel. Some of the mistakes made and the factors that contributed to the success are also listed

  16. Rapid, cost effective and non destructive determination of concentration of uranium in the process stream samples of uranium oxide plant by gamma spectrometry

    International Nuclear Information System (INIS)

    A rapid, cost effective and nondestructive gamma spectrometric method for the determination of concentration of uranium in the process stream samples of uranium oxide plant has been developed. A well type 3 x 3 NaI(Tl) detector coupled with a multichannel analyser has provided the advantages of greater accuracy and precision in results. Intensity of 185.7 keV peak of 235U is correlated with the concentration of uranium. Results compared well with those obtained by wavelength dispersive x-ray fluorescence spectrometric method and potentiometric method and a relative standard deviation of 2 % is attainable. (author)

  17. AREVA invests 610 million euro in new uranium conversion plants

    International Nuclear Information System (INIS)

    AREVA today announced the launch of the Comurhex II project which will see the group build new uranium conversion facilities on the Malvesi site in Narbonne and Tricastin. Through this 610 million euro investment, AREVA aims to maintain its position as world no. 1 for conversion within a context of global nuclear energy. COMURHEX II integrates technological innovations from major R and D programs and return of experience from processes in operation for over forty years. Nuclear safety and reducing the impact on the environment were top priorities when designing the project. These future facilities will also lead to major savings of water and energy consumption and reduce effluents. The groundwork of the Comurhex II project has taken 150,000 hours of engineering over the past three years. Four hundred people will work on the site which will be launched in summer 2007. First industrial production is scheduled for 2012, based on 15,000 metric tons of uranium per year. This figure may be increased to 21,000 tons to meet market requirements

  18. Development of simulator for the uranium enrichment plant using a real-time expert system

    International Nuclear Information System (INIS)

    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)

  19. Removal of radionuclides of the uranium-radium series from polluted soil by wheat plants

    International Nuclear Information System (INIS)

    To study the problem of the removal of radionuclides of uranium-radium series (226Ra, 230Th, 210Pb and U) with wheat crops out of contaminated soils, connections between amounts of nuclides in soil and in straw are studied. It is shown that the rate of soil self-purification of radionuclides of uranium-radium series at the expense of their removal by the crop is lower than at the expence of migration into below-lying horizons of soil. Ca content in soil reduces radionuclide transfer from soil to plants

  20. Stabilization of wasten unusable from uranium industry by planting of vegeration

    International Nuclear Information System (INIS)

    The uranium industry (extraction and treatment of the mineral ores) produces a large volume of wasten unusable for recuperating uranium but which nevertheless constitutes an environmental risk and which disfigures the latter. One solution to this problem is the planting of vegetation on the waste rips. The conditions to be fulfilled in this operations are described. It appears that no universal technique exists, but that from among those who are responsible for different scientific disciplines, we ought to gain knowledge of local parameters in such a way as to achieve the integration of an old industrial site in the general landscape

  1. UDAD, Radiation Exposure to Man at Uranium Processing Plant

    International Nuclear Information System (INIS)

    1 - Description of problem or function: The Uranium Dispersion and Dosimetry (UDAD) program provides estimates of potential radiation exposure to individuals and to the general population in the vicinity of a uranium processing facility such as a uranium mine or mill. Only transport through the air is considered. Exposure results from inhalation, external irradiation from airborne and ground- deposited activity, and ingestion of foodstuffs. Individual dose commitments, population dose commitments, and environmental dose commitments are computed. The program was developed for application to uranium mining and milling; however, it may be applied to dispersion of any other pollutant. 2 - Method of solution: The removal of radioactive particles from a contaminated area such as uranium tailings by wind action is estimated from theoretical and empirical wind-erosion equations according to the wind speed, particle size distribution, surface roughness, and other parameters. Atmospheric concentrations of radioactivity from specific sources are calculated by means of a dispersion-deposition-resuspension model. Source depletion as a result of deposition, fallout of the heavier particulates, and radioactive decay and ingrowth of radon daughters are included in a sector-averaged, Gaussian plume dispersion model. The average air concentration at any given receptor location is assumed to be constant during each annual release period, but to increase from year to year because of resuspension. Surface contamination is estimated by including buildup from deposition, ingrowth of radio- active daughters, and removal by radioactive decay, weathering, and other environmental processes. Deposition velocity is estimated on the basis of particle size, density, and physical and chemical environmental conditions which influence the behavior of the smaller particles. Calculation of the inhalation dose to an individual is based on the ICRP Task Group Lung Model (TGLM). Estimates of the dose to

  2. Uranium deposit removal from the Oak Ridge Gaseous Diffusion Plant K-25 Building

    International Nuclear Information System (INIS)

    The Oak Ridge Gaseous Diffusion Plant went into operation as the first plant to separate uranium by the gaseous diffusion process. It was built during World War II as part of the U.S. Army Corps of Engineers' Manhattan Project. Its war-time code name was K-25, which was also the name of the first uranium separation building constructed at the installation. The K-25 building was considered an engineering miracle at the time of its construction. Built in a U shape ∼1 mile long and 400 ft wide, it housed complex and unique separation equipment. Despite its size and complexity, it was made fully operational within <2 yr after construction began. The facility operated successfully for more than 20 yr until it was placed in a standby mode in 1964. It is now clear the K-25 gaseous diffusion plant will never again be used to enrich uranium. The U.S. Department of Energy, therefore, has initiated a decontamination and decommission program. This paper discusses various procedures and techniques for addressing critical mass, uranium deposits, and safeguards issues

  3. Extraction of uranium from seawater: chemical process and plant design feasibility study

    International Nuclear Information System (INIS)

    A major assessment was made of the uranium resources in seawater. Several concepts for moving seawater to recover the uranium were investigated, including pumping the seawater and using natural ocean currents or tides directly. The optimal site chosen was on the southeastern Puerto Rico coast, with the south U.S. Atlantic coast as an alternate. The various processes for extracting uranium from seawater were reviewed, with the adsorption process being the most promising at the present time. Of the possible adsorbents, hydrous titanium oxide was found to have the best properties. A uranium extraction plant was conceptually designed. Of the possible methods for contacting the seawater with the adsorbent, a continuous fluidized bed concept was chosen as most practical for a pumped system. A plant recovering 500 tonnes of U3O8 per year requires 5900 cubic meters per second of seawater to be pumped through the adsorbent beds for a 70% overall recovery efficiency. Total cost of the plant was estimated to be about $6.2 billion. A computer model for the process was used for parametric sensitivity studies and economic projections. Several design case variations were developed. Other topics addressed were the impact of co-product recovery, environmental considerations, etc

  4. Lung Cancer Mortality among Uranium Gaseous Diffusion Plant Workers: A Cohort Study 1952–2004

    Directory of Open Access Journals (Sweden)

    LW Figgs

    2013-07-01

    Full Text Available Background: 9%–15% of all lung cancers are attributable to occupational exposures. Reports are disparate regarding elevated lung cancer mortality risk among workers employed at uranium gaseous diffusion plants.Objective: To investigate whether external radiation exposure is associated with lung cancer mortality risk among uranium gaseous diffusion workers.Methods: A cohort of 6820 nuclear industry workers employed from 1952 to 2003 at the Paducah uranium gaseous diffusion plant (PGDP was assembled. A job-specific exposure matrix (JEM was used to determine likely toxic metal exposure categories. In addition, radiation film badge dosimeters were used to monitor cumulative external ionizing radiation exposure. International Classification for Disease (ICD codes 9 and 10 were used to identify 147 lung cancer deaths. Logistic and proportional hazards regression were used to estimate lung cancer mortality risk.Results: Lung cancer mortality risk was elevated among workers who experienced external radiation >3.5 mrem and employment duration >12 years.Conclusion: Employees of uranium gaseous diffusion plants carry a higher risk of lung cancer mortality; the mortality is associated with increased radiation exposure and duration of employment.

  5. An Approach to Reduce Load on the Acid Leaching Circuit of the Commercial Uranium Recovery Plant at Jaduguda, India

    OpenAIRE

    Rao, G. V.; Prakash, S.

    1998-01-01

    The commercial uranium recovery plant at Jaduguda, Bihar, India, currently treats around 900 tonnes of ore per day from the Jaduguda mine, containing around 0.05% U3O8. Subsequent to removal of the sulphide minerals present in the ore by flotation, nearly 95% of the tailings are being treated in the acid leaching circuit to recover the uranium values. Laboratory investigations on the bulk flotation tailings revealed that around 63% of the uranium values are associated with feebly magnetic mat...

  6. Automation of remote handling in uranium and mixed oxide fuel element fabrication plants

    International Nuclear Information System (INIS)

    The subject of the analyses are plants for the fabrication or uranium oxide and uranium-plutonium mixed oxide fuel elements. The reference basis of the paper is an overview of the state-of-the-art of manufacturing technologies with regard to automation and remote handling during fuel element fabrication in national and foreign plants, and in comparabel sectors of conventional technologies. Proceeding from ambient dose rates, residence times, and technical conditions or individual doses at typical work-places during fuel element fabrication, work processes are pointed out which, taking into account technical possibilities, should be given priority when automating, and technical solutions for it are sought. Advantages and disadvantages of such measures are outlined, and reduction of radiation exposure is shown (example: mixed oxide fuel fabrication plant at Hanau). (orig./HP)

  7. Preliminary characterization of uranium rare earth from phosphates and wet phosphoric acid fertilizer plant

    International Nuclear Information System (INIS)

    A preliminary characterization of several samples of phosphate rocks (phosrock), various fertilizer products, phosphoric acid, and phosphogypsum (PG) waste product from the Philippine Phosphate Fertilizer Corporation (Philphos) was conducted. The objective is to determine the concentration of uranium, rare earth elements and other valuable resources that may be present in the phosrock and phosphoric acid for added economic benefit as well as in the various produced fertilizers and phosphogypsum for environmental purposes. At the Philphos plant in Isabel, Leyte, in-situ measurements of uranium and thorium with the use of a portable gamma ray spectrometer were undertaken on phosrocks and PG waste, including several localities within the plant particularly in areas were the wet phosphoric acid is intermediately produced prior to fertilizer production. Several feed ore phosrock samples, various fertilizer products and a PG waste sample were analyzed for uranium by fluorimetry and for other nine elements by atomic absorption spectrophotometry at the Nuclear Materials Research Section of the Philippine Nuclear Research Institute (PNRI). Similarly, the feed ore phosrock samples and two phosphoric acids produced from Egypt and Peru phosrocks were analyzed for uranium by gamma spectrometry at the Nuclear Reactor Section of PNRI. Likewise, the two phosphoric acids from Egypt and Peru phosrocks were analyzed for uranium, thorium, rare earth elements and others by Inductively Coupled Plasma Mass Spectrometry at the National Institute of Geological Sciences, University of the Philippines. Presented are the results of the in-situ gamma ray measurements and the different analytical methods used. While the results are very preliminary, the present study revealed the presence uranium and other useful resources in significant amount to warrant further investigations. (Author)

  8. The relationship of JNC and JCO in the uranium processing plant criticality accident

    International Nuclear Information System (INIS)

    On September 30th 1999, the criticality accident occurred at JCO's uranium conversion building in Tokai. The accident occurred during reconversion from U3O8 to uranium nitrate solution (UNH) with uranium enriched 18.8% and about 60 kgU. JCO contacted with JNC to supply UNH that is fuel material for the experimental fast breeder reactor 'JOYO'. JNC has contracted with JCO that had started nuclear fuel material processing business following a definite policy of Japanese government and developed SUMITOMO ADU PROCESS'. JNC made the first contract with JCO in 1985 and has made a contact every year. There had never been a problem in their products. JNC inspected products based on contract. JNC discharge our duty as customer inspecting products based on contract. As for safety control, JCO had taken licensing safety review and had been permitted to be 'a processing facility'. Therefore JNC understood that JCO produced following this license. 'The Uranium Processing Plant Criticality Accident Investigation' showed that JCO had been taking a different method from the permit and violating the license. However JNC had never been explained about that and JCO's operation procedures had never described about that. Therefore the Criticality Accident couldn't be avoided. This report describes the relationship of JNC and JCO in the uranium reconversion contract for JOYO, atomic development policy of Japanese government, process to the order and the contents of contract. (author)

  9. Pilot plant studies on the treatment of El Atshan Uranium Ores, Eastern Desert, Egypt

    International Nuclear Information System (INIS)

    The present work deals with studying the different processes leading to the preparation of commercial uranium concentrate (yellow cake) from El Atshan granitic ore material (0.077%U) after acid leading of the latter, the two common extraction techniques of uranium from the obtained sulphate leach liquor; namely, anion exchange rein and solvent extraction have been studied. The studied leaching and extraction conditions-realized on the lab scale-were applied to inches pilot plant unit (capacity 150 kg ore). An average leaching leaching efficiency exceeding 88% has been achieved. Using anion exchange resin, it has been possible to prepare a uranium peroxide concentrate assaying a uranium content of about 67% U3 O8. Only trace amount of Ca, Fe, Po4, Cr and Pb have been detected. On the other hand, sodium uranate, as a uranium precipitate was prepared from the strip solution of the loaded solvent (di-2-ethyl phosphoric acid concerned with the evaluation of a new optimized technique for the principle of chloramine-T method used for insulin iodination for the modified procedure can be carried out under normal condition of room temperature, employed longer reaction times and omitted the addition of inorganic reducing salts maintaining efficient iodination and avoiding denaturation to obtain labels of exceedingly high specific activity and small quantities of insulin for in vitro usage in the investigation of human erythrocytes 125 I-inulin binding capacity in normal and in some disease status. 9 figs., 2 tabs

  10. DOE-ARN proposed method to verify uranium inventory at the Pilcaniyeu Gaseous Diffusion Enrichment Plant

    International Nuclear Information System (INIS)

    The Pilcaniyeu Gaseous Diffusion Plant is located near San Carlos de Bariloche, Argentina, in the Province of Rio Negro. It is designed to enrich uranium to a nominal level of 5% 235U and a nominal capacity of 20,000 separative work units per year. Since 1993, this facility has been under international safeguards. New measurement methods were required to accurately verify Pilcaniyeu's uranium inventory, because this is the first gaseous diffusion enrichment plant to come under International Atomic Energy Agency (IAEA) safeguards. In 1992, the United States and Argentina embarked on a cooperative effort to accomplish this task. Several nondestructive measurement experiments were performed at gaseous diffusion plants in the United State and at the Pilcaniyeu plant in Argentina. It was determined that passive gamma-ray measurement is the technique of choice for Pilcaniyeu. Mathematical algorithms were developed that accurately estimate the uranium inventory of the facility. This paper summarizes the measurement activities conducted under Argentine- US cooperation, discusses the proposed methods, and proposes a process to validate the procedure for IAEA use. (author)

  11. Rapid determination of uranium isotopes in low and intermediate level wastes from nuclear power plants by alpha spectrometry

    International Nuclear Information System (INIS)

    A simple and fast method for uranium isotopes determination in low and intermediate level wastes from nuclear power plants using extraction chromatography is described. Following sample preparation, uranium is pre-concentrated by precipitation with iron(III) hydroxide and then separated using Dowex AG 1X8, 100-200mesh, resin. The separated uranium is electrodeposited onto stainless-steel discs and then measured by alpha spectrometry and the results were analyzed using WinALPHA software. The procedure was evaluated using 232U radiotracer. USGS uranium standard and intercomparison program were used as quality tools. (author)

  12. Characterization of past and present solid waste streams from the Plutonium-Uranium Extraction Plant

    International Nuclear Information System (INIS)

    During the next two decades the transuranic wastes, now stored in the burial trenches and storage facilities at the Hanford Site, are to be retrieved, processed at the Waste Receiving and Processing Facility, and shipped to the Waste Isolation Pilot Plant near Carlsbad, New Mexico for final disposal. Over 7% of the transuranic waste to be retrieved for shipment to the Waste Isolation Pilot Plant has been generated at the Plutonium-Uranium Extraction (PUREX) Plant. The purpose of this report is to characterize the radioactive solid wastes generated by PUREX using process knowledge, existing records, and oral history interviews. The PUREX Plant is currently operated by the Westinghouse Hanford Company for the US Department of Energy and is now in standby status while being prepared for permanent shutdown. The PUREX Plant is a collection of facilities that has been used primarily to separate plutonium for nuclear weapons from spent fuel that had been irradiated in the Hanford Site's defense reactors. Originally designed to reprocess aluminum-clad uranium fuel, the plant was modified to reprocess zirconium alloy clad fuel elements from the Hanford Site's N Reactor. PUREX has provided plutonium for research reactor development, safety programs, and defense. In addition, the PUREX was used to recover slightly enriched uranium for recycling into fuel for use in reactors that generate electricity and plutonium. Section 2.0 provides further details of the PUREX's physical plant and its operations. The PUREX Plant functions that generate solid waste are as follows: processing operations, laboratory analyses and supporting activities. The types and estimated quantities of waste resulting from these activities are discussed in detail

  13. Characterization of past and present solid waste streams from the Plutonium-Uranium Extraction Plant

    Energy Technology Data Exchange (ETDEWEB)

    Pottmeyer, J.A.; Weyns, M.I.; Lorenzo, D.S.; Vejvoda, E.J. [Los Alamos Technical Associates, Inc., NM (US); Duncan, D.R. [Westinghouse Hanford Co., Richland, WA (US)

    1993-04-01

    During the next two decades the transuranic wastes, now stored in the burial trenches and storage facilities at the Hanford Site, are to be retrieved, processed at the Waste Receiving and Processing Facility, and shipped to the Waste Isolation Pilot Plant near Carlsbad, New Mexico for final disposal. Over 7% of the transuranic waste to be retrieved for shipment to the Waste Isolation Pilot Plant has been generated at the Plutonium-Uranium Extraction (PUREX) Plant. The purpose of this report is to characterize the radioactive solid wastes generated by PUREX using process knowledge, existing records, and oral history interviews. The PUREX Plant is currently operated by the Westinghouse Hanford Company for the US Department of Energy and is now in standby status while being prepared for permanent shutdown. The PUREX Plant is a collection of facilities that has been used primarily to separate plutonium for nuclear weapons from spent fuel that had been irradiated in the Hanford Site`s defense reactors. Originally designed to reprocess aluminum-clad uranium fuel, the plant was modified to reprocess zirconium alloy clad fuel elements from the Hanford Site`s N Reactor. PUREX has provided plutonium for research reactor development, safety programs, and defense. In addition, the PUREX was used to recover slightly enriched uranium for recycling into fuel for use in reactors that generate electricity and plutonium. Section 2.0 provides further details of the PUREX`s physical plant and its operations. The PUREX Plant functions that generate solid waste are as follows: processing operations, laboratory analyses and supporting activities. The types and estimated quantities of waste resulting from these activities are discussed in detail.

  14. Role of uranium speciation on its bioaccumulation, transfer and toxicity in plants. Application to phyto-remediation

    International Nuclear Information System (INIS)

    Uranium is both a radiological and a chemical toxic, which naturally occurs in the environment as a trace element. Metal accumulation and distribution in plants is modulated by speciation. The aim of this PhD work was thus to assay uranium accumulation, intra planta repartition and toxicity according to its speciation in solution. Acquired knowledge will be applied in phyto-remediation technologies. We exposed three plant species (sunflower, oilseed rape and wheat) to a panel of hydroponic media containing one or two predominant uranium chemical forms. After exposition in these various contaminated media, we evaluated uranium content in plant organs by ICP-MS. In order to investigate uranium repartition and localization at organ/tissue and cellular scales, we carried out four complementary imaging techniques. The uranium repartition within soluble and membrane fractions in roots and shoot was assayed after fractionation and separation through a chromatography column. In parallel, we used X-ray absorption spectroscopy to determine the molecular-level structure of chemical species formed by uranium in exposure media and plant samples. Finally, we explored toxic effects of uranium on plant growth and metabolism. Our results revealed three schema of accumulation according to the uranium speciation in the exposure medium: when exposed to UO22+ free ion, root accumulation is high, but uranium transfer to the shoots is limited. Uranium is immobilized by adsorption on root surface and precipitation on root cell walls, associated with phosphorus and calcium. The existence of uranium-binding proteins is also suggested. When complexed with phosphate, root accumulation is considerably reduced and translocation becomes negligible. Uranium is precipitated as described above. Conversely, complexation with carbonate or citrate reduces root accumulation but drastically increases translocation to the shoots. If some uranyl phosphate precipitates are still found in root and shoot, a

  15. A study on possible use of Urtica dioica (common nettle) plants as uranium (234U, 238U) contamination bioindicator near phosphogypsum stockpile

    International Nuclear Information System (INIS)

    The aim of this study was to determine uranium concentrations in common nettle (Urtica dioica) plants and corresponding soils samples which were collected from the area of phosphogypsum stockpile in Wislinka (northern Poland). The uranium concentrations in roots depended on its concentrations in soils. Calculated BCF and TF values showed that soils characteristics and air deposition affect uranium absorption and that different uranium species have different affinities to U. dioica plants. The values of 234U/238U activity ratio indicate natural origin of these radioisotopes in analyzed plants. Uranium concentration in plants roots is negatively weakly correlated with distance from phosphogypsum stockpile. (author)

  16. Cost update technology, safety, and costs of decommissioning a reference uranium hexafluoride conversion plant

    International Nuclear Information System (INIS)

    The purpose of this study is to update the cost estimates developed in a previous report, NUREG/CR-1757 (Elder 1980) for decommissioning a reference uranium hexafluoride conversion plant from the original mid-1981 dollars to values representative of January 1993. The cost updates were performed by using escalation factors derived from cost index trends over the past 11.5 years. Contemporary price quotes wee used for costs that have increased drastically or for which is is difficult to find a cost trend. No changes were made in the decommissioning procedures or cost element requirements assumed in NUREG/CR-1757. This report includes only information that was changed from NUREG/CR-1757. Thus, for those interested in detailed descriptions and associated information for the reference uranium hexafluoride conversion plant, a copy of NUREG/CR-1757 will be needed

  17. 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.

  18. Magnesio-thermic reduction of UF4 to uranium metal : plant operating experience

    International Nuclear Information System (INIS)

    Uranium Metal Plant has switched over from calcio-thermy to magnesio-thermy for production of uranium ingots. In this paper, the plant operating experience for magnesio-thermic reduction is described. Based on trials, the production has been stepped up from 40 kg ingots to 200 kg ingots. The operating parameters optimised include : heating schedule, UF4 quality, magnesium quantity and quality, and particle size. The effect of quality of refractory lining has been discussed. Conditions for lining are optimised with regard to type of material used and size. Developmental work has also been carried out on use of pelletised charge and on use of graphite sleeves. Some experience in the machining of ingots for removal of surface slag is also discussed. Impurity problems, occasionally encountered, have been investigated and results are discussed. Based on the experience gained, specifications for operation have been laid down, and areas for further improvement are identified. (author). 5 refs., 1 fig., 1 tab

  19. International safeguards at the feed and withdrawal area of a gas centrifuge uranium enrichment plant

    International Nuclear Information System (INIS)

    This paper discusses the application of International Atomic Energy Agency (IAEA) safeguards at a model gas centrifuge uranium enrichment plant designed for the production of low-enriched uranium; particular emphasis is placed upon the verification by the IAEA of the facility material balance accounting. After reviewing the IAEA safeguards objectives and concerns at such a plant, the paper describes the material accountancy performed by the facility operator, and discusses strategies by which the operator might attempt to divert a portion of the declared nuclear materials. Finally, the paper discusses the verification of the declared material balance, including sampling strategies, attributes and variables measurements, and nondestructive measurements to improve the efficiency of the inspection measures

  20. Screening of plant species for phytoremediation of uranium, thorium, barium, nickel, strontium and lead contaminated soils from a uranium mill tailings repository in South China.

    Science.gov (United States)

    Li, Guang-yue; Hu, Nan; Ding, De-xin; Zheng, Ji-fang; Liu, Yu-long; Wang, Yong-dong; Nie, Xiao-qin

    2011-06-01

    The concentrations of uranium, thorium, barium, nickel, strontium and lead in the samples of the tailings and plant species collected from a uranium mill tailings repository in South China were analyzed. Then, the removal capability of a plant for a target element was assessed. It was found that Phragmites australis had the greatest removal capabilities for uranium (820 μg), thorium (103 μg) and lead (1,870 μg). Miscanthus floridulus had the greatest removal capabilities for barium (3,730 μg) and nickel (667 μg), and Parthenocissus quinquefolia had the greatest removal capability for strontium (3,920 μg). In this study, a novel coefficient, termed as phytoremediation factor (PF), was proposed, for the first time, to assess the potential of a plant to be used in phytoremediation of a target element contaminated soil. Phragmites australis has the highest PFs for uranium (16.6), thorium (8.68), barium (10.0) and lead (10.5). Miscanthus floridulus has the highest PF for Ni (25.0). Broussonetia papyrifera and Parthenocissus quinquefolia have the relatively high PFs for strontium (28.1 and 25.4, respectively). On the basis of the definition for a hyperaccumulator, only Cyperus iria and Parthenocissus quinquefolia satisfied the criteria for hyperaccumulator of uranium (36.4 μg/g) and strontium (190 μg/g), and could be the candidates for phytoremediation of uranium and strontium contaminated soils. The results show that the PF has advantage over the hyperaccumulator in reflecting the removal capabilities of a plant for a target element, and is more adequate for assessing the potential of a plant to be used in phytoremediation than conventional method. PMID:21523506

  1. Modification of fluorimetric method of uranium analysis for Jaduguda Plant samples

    International Nuclear Information System (INIS)

    Fluorimetry is one of the most sensitive instrumental methods of estimating uranium. The method followed at present involves the extraction of uranium with ethyl acetate in presence of saturated solution of aluminium nitrate. After extraction, an aliquot of the extract is pipetted into platinum dishes specially made for fluorimetric work and the solvent is evaporated under an infra-red-lamp. The residue is fused with about 0.4 gm of sodium fluoride-sodium carbonate (1:4 mixture) at a temperature of about 800degC for 3 minutes using a muffle furnace. The fused mass is cooled and the fluorescence of the resultant bead is measured. The samples analysed by fluorimetric method are : (1) break through, (2) semi pregnant (3) barren diversion, (4) second eluates, (5) grab sample of elute, (6) secondary filter cake, (7) barren liquors, (8) leach tailings, and (9) plant tailings. While using ethyl acetate, extractions are done in nitrate medium whereas most of the samples studied in this investigation are in sulphuric acid medium. Hence a solvent suited for sulphate medium was felt to be more useful. Amines are being used extensively to remove uranium from sulphate liquors as an anion. Alamine-336 has been used in R and D studies for solvent extraction of the uranium from Jaduguda leach liquors. Since it was found to be a good extractant, the same solvent was selected for extraction for fluorimetric analysis of uranium in place of ethyl acetate aluminium nitrate. It was found that Alamine-336 can be used in place of ethyl acetate aluminium nitrate for uranium extraction for fluorimetric determination with the same accuracy as in the case of ethyl acetate aluminium nitrate. (author). 2 refs., 3 figs., 5 tabs

  2. Uranium and radium in water samples around the Nikola Tesla B lignite-fired power plant - Obrenovac, Serbia

    OpenAIRE

    Žunić Zora S.; Mietelski Jerzy W.; Radanović Sanja B.; Kierepko Renata; Ciotoli Giancarlo; Čeliković Igor T.; Ujić Predrag N.; Kisić Dragica M.; Bartyzel Miroslaw; Bogacz Joanna; Udovičić Vladimir I.; Simović Rodoljub D.

    2011-01-01

    This paper deals with the analysis of natural radionuclide content in 23 water samples collected in the vicinity of the Nikola Tesla B thermal power plant, Serbia. All samples were analyzed for 226Ra and uranium isotopes (238U, 234U) activity using radiochemical methods and alpha spectrometry. Obtained results show that the activity concentrations for uranium and radium in the water around the thermal power plant are low when compared to those from areas across Serbia with their enhance...

  3. A study on possible use of Urtica dioica (common nettle) plants as uranium (234U, 238U) contamination bioindicator near phosphogypsum stockpile

    OpenAIRE

    Olszewski, Grzegorz; Boryło, Alicja; Skwarzec, Bogdan

    2015-01-01

    The aim of this study was to determine uranium concentrations in common nettle (Urtica dioica) plants and corresponding soils samples which were collected from the area of phosphogypsum stockpile in Wiślinka (northern Poland). The uranium concentrations in roots depended on its concentrations in soils. Calculated BCF and TF values showed that soils characteristics and air deposition affect uranium absorption and that different uranium species have different affinities to U. dioica plants. The...

  4. Biogeochemical investigation in south eastern Andhra Pradesh: the distribution of rare earths, thorium and uranium in plants and soils

    Energy Technology Data Exchange (ETDEWEB)

    Raju, K.K.; Raju, A.N. [Sri Venkateswara Univ., Tirupati (India). Dept. of Geology

    2000-09-01

    The concentration of rare earth elements (REE), thorium and uranium were determined by inductively coupled plasma mass spectrometry (ICP-MS) in the plant species, Pterocarpus santalinus, P. marsupium and P. dalbergioides, and the soils on which they were growing. Higher concentrations of lanthanum (La), cerium (Ce) were observed in both plants and soils. Large amounts of thorium and uranium were found in the soil. In all tree species, the concentration of REEs were higher in the heartwood than the leaves. The heartwood of P. santalinus accumulated larger quantities of uranium (average concentration of 1.22 ppm) and thorium (mean value of 2.57 ppm) than the other two species. (orig.)

  5. Biogeochemical investigation in south eastern Andhra Pradesh: the distribution of rare earths, thorium and uranium in plants and soils

    International Nuclear Information System (INIS)

    The concentration of rare earth elements (REE), thorium and uranium were determined by inductively coupled plasma mass spectrometry (ICP-MS) in the plant species, Pterocarpus santalinus, P. marsupium and P. dalbergioides, and the soils on which they were growing. Higher concentrations of lanthanum (La), cerium (Ce) were observed in both plants and soils. Large amounts of thorium and uranium were found in the soil. In all tree species, the concentration of REEs were higher in the heartwood than the leaves. The heartwood of P. santalinus accumulated larger quantities of uranium (average concentration of 1.22 ppm) and thorium (mean value of 2.57 ppm) than the other two species. (orig.)

  6. Radon transport from uranium mill tailings via plant transpiration. Final report

    International Nuclear Information System (INIS)

    Radon exhalation by vegetation planted on bare or soil-covered uranium mill wastes was studied based on an assumption that radon transport from soil to atmosphere via plants takes place in the transpiration stream. Results show that radon exhalation by plants is inversely related to water transpired, primarily a dilution effect. Radon released appeared directly related to leaf area, suggesting that radon is carried into the plant by mass flow in water; however, once within the plant, radon very likely diffuses through the entire leaf cuticle, while water vapor diffuses primarily through open stomates. Application of a computerized model for water transpiration to radon exhalation is not immediately useful until the role of water in radon transport is defined throughout the continuum from rooting medium to the atmosphere. Until then, a simple calculation based on leaf area index and Ra-226 concentration in the rooting medium can provide an estimate of radon release from revegetated wastes containing radium

  7. Decontamination and Decommissioning Experience at a Sellafield Uranium Purification Plant

    International Nuclear Information System (INIS)

    Built in the 1950's, this plant was originally designed to purify depleted uranyl nitrate solution arising from reprocessing operations at the Primary Separation and Head End Plant (Fig. 1). The facility was used for various purposes throughout its life cycle such as research, development and trial based processes. Test rigs were operated in the building from the 1970's until 1984 to support development of the process and equipment now used at Sellafield's Thermal Oxide Reprocessing Plant (THORP). The extensive decommissioning program for this facility began over 15 years ago. Many challenges have been overcome throughout this program such as decommissioning the four main process cells, which were very highly alpha contaminated. The cells contained vessels and pipeline systems that were contaminated to such levels that workers had to use pressurized suits to enter the cells. Since decommissioning at Sellafield was in its infancy, this project has trialed various decontamination/decommissioning methods and techniques in order to progress the project, and this has provided valuable learning for other decommissioning projects. The project has included characterization, decontamination, dismantling, waste handling, and is now ready for demolition during late 2005, early 2006. This will be the first major facility within the historic Separation Area at Sellafield to be demolished down to base slab level. The lessons learnt from this project will directly benefit numerous decommissioning projects as the cleanup at Sellafield continues. (authors)

  8. Recent Pilot Plant Experience on Alkaline Leaching of Low Grade Uranium Ore in India

    International Nuclear Information System (INIS)

    Uranium deposits in India are low grade and are relatively smaller in extent as compared to present worldwide commercial practice. So far, the vein type deposits of Singhbhum Thrust Belt (STB) are being exploited for meeting the Indian requirements of uranium. The deposits are currently processed by acid leaching in the mills located at Jaduguda and Turamdih near Jamshedpur in Jharkhand State of India. The deposits at Jaduguda and Narwapahar are being mined by underground mining and are processed in Jaduguda mill using airagitated Pachucas. The deposits at Banduhurang and Turamdih are being mined by open cast and underground mining respectively and are processed at Turamdih by acid leaching in mechanically agitated reactors. The occurrences of uranium in North East and Northern part of Kadapa basin are relatively moderate in size and are expected to be processed in the near future by acid leaching. Uranium is also found to occur near Tummalapalle in granitic and limestone host rocks in Southern part of Kadapa basin (Andhra Pradesh) and in Gogi in Bhima basin (Karnataka). The deposit in Tummalapalle is relatively lower in grade (≈ 0.042% U3O8) but is a reasonably large reserve, whereas that in Gogi is rich in uranium content (≈0.18% U3O8) but is relatively small reserve. Laboratory tests based on alkaline leaching have been carried out on both types of deposits. Studies for Tummalapalle deposits have been extended to pilot plant level and a complete flow sheet has been established with the regeneration and recirculation of lixiviants and recovery of sodium sulphate as a by-product. The process involves alkaline leaching under oxygen pressure in batch type and/or continuous leach reactor using sodium carbonate/bicarbonate as a leaching media and uranium is recovered as sodium diuranate. Based on the techno-economic evaluation of the process, an industrial scale mill (3 000 tonnes ore/day) is being set up at Tummalapalle in Andhra Pradesh by Uranium Corporation of

  9. Development of a computer systems for operational data acquisition of uranium isotopic enrichment pilot plant

    International Nuclear Information System (INIS)

    A pilot plant for uranium enrichment using the jet nozzle process was transfered from Federal Republic of Germany to Brazil, to train Brazilian technicist in its operation and to improve the process. This pilot plant is monitored by a data acquisition system and the possibility of faulty events would cause serious dificulties, as far as maintenance is concerned (for instance, unvailable special components). It is described the development of a new system, which is proposed in order to minimize difficulties with maintenance that utilizes in the assembling integrated circuits of large scale of integration. It is controlled by a microcomputer. (Author)

  10. Air strikes on uranium enrichment plants as potential sources of radioecological danger

    Directory of Open Access Journals (Sweden)

    Živanov Dragan

    2007-01-01

    Full Text Available According to the Non Proliferation Treaty (NPT, the signatory countries are not forbidden to preform uranium enrichment for peaceful purposes. However, if there is a justified doubt that the uranium enrichment is performed with the aim to produce nuclear weapons, this certainly causes great concern. In this case, the international community can apply pressure to a certain country if it determines that the country does not want to cease activities of making its own nuclear weapons. The international community pressure on the country can be intesified until its political leadership is not made to question and cease all activities of producing nuclear weapons. This pressure can be political, economic, and as a last resort-military. As a gesture of goodwill the country can stop the uranium enrichment process. In this way, the country shows that it finally gives up the intention to produce nuclear weapons. However, when military pressure is applied, i.e. military strikes (air strikes for example on nuclear plants used for uranium enrichment, this certainly creates a risk of releasing radioactivity into the environment. That is why the aim of this paper is to signal this very fact. Using military force in these cases leads to additional radioactive contamination of the environment, so this way of solving conflicts should be avoided within the international community.

  11. Accumulation of uranium by aquatic plants in field conditions: prospects for phytoremediation.

    Science.gov (United States)

    Favas, Paulo J C; Pratas, João; Varun, Mayank; D'Souza, Rohan; Paul, Manoj S

    2014-02-01

    A study was undertaken to determine Uranium concentrations in water and aquatic plants in the uraniferous region of Beiras, Central Portugal. Samples were collected from running water (n=200) at places where aquatic species were observed. Plant samples were collected from 28 species of submerged, free-floating and rooted emergent plants including 2 bryophytes and 1 pteridophyte. Uranium concentrations in surface waters ranged from 0.23 to 1,217 μg L(-1). The aquatic plant species studied, including several previously untested species, exhibited the ability to accumulate U in concentrations many times that of the ambient water. In general submerged plants exhibited higher U content followed by rooted emergent and free floating species. The highest U concentrations were observed in the bryophyte Fontinalis antipyretica (up to 4,979 mg kg(-1)) followed by Callitriche stagnalis (1963mgkg(-1)), Callitriche hamulata (379 mg kg(-1)), Ranunculus peltatus subsp. saniculifolius (243 mg kg(-1)), Callitriche lusitanica (218 mg kg(-1)), and Ranunculus trichophyllus (65.8 mg kg(-1)). In two out of three rooted emergent species U seemed to be preferentially partitioned in rhizome/roots with highest rhizome U content recorded in Typha latifolia (380 mg kg(-1)). Among the free-floating species, the highest U content (42.5 mg kg(-1)) was seen in Lemna minor. The bryophyte F. antipyretica and Callitrichaceae members seem to be promising candidates for the development of phytofiltration methodologies based on U accumulation, abundance and biomass production. PMID:24239820

  12. Model of a Generic Natural Uranium Conversion Plant ? Suggested Measures to Strengthen International Safeguards

    Energy Technology Data Exchange (ETDEWEB)

    Raffo-Caiado, Ana Claudia [ORNL; Begovich, John M [ORNL; Ferrada, Juan J [ORNL

    2009-11-01

    This is the final report that closed a joint collaboration effort between DOE and the National Nuclear Energy Commission of Brazil (CNEN). In 2005, DOE and CNEN started a collaborative effort to evaluate measures that can strengthen the effectiveness of international safeguards at a natural uranium conversion plant (NUCP). The work was performed by DOE s Oak Ridge National Laboratory and CNEN. A generic model of a NUCP was developed and typical processing steps were defined. Advanced instrumentation and techniques for verification purposes were identified and investigated. The scope of the work was triggered by the International Atomic Energy Agency s 2003 revised policy concerning the starting point of safeguards at uranium conversion facilities. Prior to this policy only the final products of the uranium conversion plant were considered to be of composition and purity suitable for use in the nuclear fuel cycle and therefore, subject to the IAEA safeguards control. DOE and CNEN have explored options for implementing the IAEA policy, although Brazil understands that the new policy established by the IAEA is beyond the framework of the Quadripartite Agreement of which it is one of the parties, together with Argentina, the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) and the IAEA. Two technical papers on this subject were published at the 2005 and 2008 INMM Annual Meetings.

  13. Plant and soil relationships of uranium and thorium decay series radionuclides - a review

    International Nuclear Information System (INIS)

    The behavior of radionuclides of the uranium (U) and thorium (Th) decay series in terrestrial systems is of interest because of environmental effects of mining and disposal activities related to nuclear power plant fuels. The soil-plant relationships of U, Th, and polonium (Pb), and some other daughter radionuclides, notably radium (226Ra), are not well understood. Most studies have been concerned with relative uptake of these radionuclides by various plant species. Plant concentrations have been related to total contents of these radionuclides in the soil as a plant/soil concentration ratio (CR), even though the fraction of these radionuclides, which may be available to plants, is not well known. These CR values have been used to predict transport of radionuclides and other elements of interest through the food chain as well as for other purpose including biogeochemical exploration for U. Little information is available on uptake and transport mechanisms of radionuclides in plants. However, the mechanisms relating to Ca uptake and translocation in plants may be similar to those of some radionuclides, especially 226Ra. Son chemical reactions of these radionuclides also have not been studied as well as those of plant nutrients, although knowledge of the effects of soil pH, soil texture, and organic matter content on uptake, as well as mobility in soil of these radionuclides, has been gained in recent years. 45 refs., 13 tabs

  14. Dismantling and decommissioning of an Uranium processing plant at Andujar (Spain)

    International Nuclear Information System (INIS)

    The dismantling and decommissioning of the Uranium Processing Plant at Andujar is the first experience of such a kind in Spain. The factory houses almost 1 million cubic meters of uranium esterile ores concentrated in two different landfills covering 94,000 square meters, as a results of mining activities between 1959 and 1981. The project will stabilize both landfill containers ''in situ'' by using the products obtained after dismantling factory buildings and installation of processing. Decommissioning will take place at the end of 1993. Before dismantling works started, a number of geological, geotechnical, sysmologic, environmental, migration parameters of radionuclides from the landfill and socio-economical studies were conducted. The different phases of wastes conditioning and the updated situation of work plan are described

  15. Determination of uranium in drinking water in the vicinity of nuclear power plants by ICP-MS

    International Nuclear Information System (INIS)

    Objective: To ascertain the concentrations of uranium in drinking water around nuclear power plants. Methods: A total of 106 water samples were collected from June 2009 to March 2010 in Jiangsu, Zhejiang, Liaoning and Shandong provinces. Inductively coupled plasma-mass spectrometry(ICP-MS) was applied to determine uranium content in local water source and drinking water. The detection limit of U was 0.8 ng/L. The recovery was 100.9%. Results: The uranium concentrations in all samples were less than 15μg/L which was the limit given by World Health Organization (WHO). Conclusions: The concentration of uranium in water sources was as follows: Liaoning>Shandong>Jiangsu>Zhejiang.The concentration of uranium in drinking water was maximal in Shandong Province and minimal in Zhejiang Province. (authors)

  16. Soil-to-Plant Transfers of Uranium Series Radionuclides in Natural and Contaminated Settings

    International Nuclear Information System (INIS)

    Uranium and related decay-chain radionuclides remain important subjects of study for a number of reasons. Uranium has the potential to be chemically toxic near mining and processing facilities, and the decay-chain radionuclides can contribute substantially to radiation dose. Establishing an air quality standard for U in Canada has also been tentatively based on its accumulation and toxicity in soil. This paper summarizes two studies. The first investigated the mobility in soil, uptake by plants and eco-toxicity of U near a U refining facility. Because of the presence of co-contaminants, a large number of other elements were measured to fully characterize the samples. In general, the soil solid/liquid partition coefficients, Kd, for U were high enough that leaching is not a dominant process. Plant/soil concentration ratios (CRs) were higher than for background sites. The second study measured plant/soil CRs for 210Pb, 210Po, 226Ra, 228Ra, 228T, 230Th, 232Th and 238U on a series of sites across Canada, with emphasis on background sites with possible human food-chain connections. In addition, a large suite of metals was analyzed in the same samples. The correlation of plant/soil CRs among the various radionuclides and stable elements will be investigated, and related to soil and site properties. (author)

  17. Preconceptual design studies and cost data of depleted uranium hexafluoride conversion plants

    International Nuclear Information System (INIS)

    One of the more important legacies left with the Department of Energy (DOE) after the privatization of the United States Enrichment Corporation is the large inventory of depleted uranium hexafluoride (DUF6). The DOE Office of Nuclear Energy, Science and Technology (NE) is responsible for the long-term management of some 700,000 metric tons of DUF6 stored at the sites of the two gaseous diffusion plants located at Paducah, Kentucky and Portsmouth, Ohio, and at the East Tennessee Technology Park in Oak Ridge, Tennessee. The DUF6 management program resides in NE's Office of Depleted Uranium Hexafluoride Management. The current DUF6 program has largely focused on the ongoing maintenance of the cylinders containing DUF6. However, the long-term management and eventual disposition of DUF6 is the subject of a Programmatic Environmental Impact Statement (PEIS) and Public Law 105-204. The first step for future use or disposition is to convert the material, which requires construction and long-term operation of one or more conversion plants. To help inform the DUF6 program's planning activities, it was necessary to perform design and cost studies of likely DUF6 conversion plants at the preconceptual level, beyond the PEIS considerations but not as detailed as required for conceptual designs of actual plants. This report contains the final results from such a preconceptual design study project. In this fast track, three month effort, Lawrence Livermore National Laboratory and Bechtel National Incorporated developed and evaluated seven different preconceptual design cases for a single plant. The preconceptual design, schedules, costs, and issues associated with specific DUF6 conversion approaches, operating periods, and ownership options were evaluated based on criteria established by DOE. The single-plant conversion options studied were similar to the dry-conversion process alternatives from the PEIS. For each of the seven cases considered, this report contains information on

  18. Occurrence of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in uranium mine-Caldas uranium mining and extraction plant, Brazil (CUMEP)

    International Nuclear Information System (INIS)

    The sulfated minerals present in mining areas may cause serious environmental problems due to the action of chemolithotrophic bacteria from genus Acithiobacillus, represented mainly by Acithiobacillus ferrooxidans and Acithiobacillus thiooxidans. These microorganisms are able to oxidize mineral sulfates, elementary sulfur and ferrous ion (A. ferrooxidans), as well are capable of mobilizing radionuclide as uranium to the environment. In this context, this study aimed at investigating the occurrence and the fluctuation of A. ferrooxidans and A. thiooxidans populations within the mine effluents, tailing dam and waste rocks of the Caldas Uranium Mining arid Extraction Plant (CUMEP) in Minas Gerais State - Brazil. Samples from 16 sites were evenly taken monthly in the CUMEP, during 28 months. The oxi-reduction potential, pH and temperature values were determined at the Radioecology Laboratory. The Most Probable Number technique was applied using a series of five tubes for selective counting of A. ferrooxidans and A. thiooxidans. Each sample was submitted to serial dilutions using Tween 80 and sterilized water (pH=2.0) and subsequently transferred into assay tubes containing T and K with ferrous ion and also elementary sulfur, as energy source, for detection of A. ferrooxidans and A. thiooxidans, respectively. Populations of A. ferrooxidans and A. thiooxidans presented seasonal quantitative fluctuations at the different studied sites. A. ferrooxidans showed higher or equal frequency to that observed for A. thiooxidans; as consequence, they were considered the predominant bacteria in this environment. In the majority of the sites, the highest values for the frequency and counting of A. ferrooxidans and A. thiooxidans were observed during the rainy period (October to March). The relative seasonal behavior when several variables are evaluated simultaneously indicated that, due to the high values of oxi-reduction potential, the low values of pH, the detection of the highest

  19. TAMARA - an uranium extraction pilot plant for demonstration of computerized process-control in reprocessing. Pt. 1

    International Nuclear Information System (INIS)

    An uranium extraction pilot plant with in-line instrumentation is described. The plant was constructed in the course of the development and demonstration of a computer-based control of nuclear fuel reprocessing processes and is connected with the process computer system CALAS. The results gained until now are presented and discussed, and the future work suggested is mentioned. (orig.)

  20. Evaluation of the solvent extraction organic phase in a uranium extraction plant / Reinier Hendrik van der Ryst

    OpenAIRE

    Van der Ryst, Reinier Hendrik

    2010-01-01

    Using kerosene as an aromatic organic diluent in the liquid–liquid separation process for the extraction of uranium in the solvent extraction section of the AngloGold Ashanti South Uranium Plant near the town of Orkney in South Africa, incurs a multitude of safety, health and environmental problems. A possible solution may be to replace the currently used aromatic–based organic diluent with an aliphatic–based organic diluent. A range of aliphatic organic diluents were tested...

  1. Implementation of the MARSSIM to Evaluate the Final Status After Decommissioning Uranium Conversion Plant

    International Nuclear Information System (INIS)

    The decommissioning project of Uranium Conversion Plant was launched in 2001 and completed at the first half of 2011. The final stage of decommissioning process was the release of a site and building from regulatory control. KAERI carried out a final status survey based on the guidance provided in the MARSSIM (Multi-Agency Radiation Survey and Site Investigation Manual). The Uranium Conversion Plant was used to manufacture UO2 powder for CANDU fuel, the plant was contaminated only natural uranium. In this study, plans for the final status survey and release criteria for a site were established by applying the MARSSIM procedures. The survey design for the final status survey of the UCP site and buildings was carried out based on the statistical test of the results form scoping and characterization survey. The site and buildings were classified based on the potential contamination by using measured and calculated results. The results of the final status survey were satisfied the release criteria based on the measured data from a site and building. The summarized final status survey results are given in Figure 1 shows detail residual contamination level in Class 1. The results of the final status survey are sufficiently lower than the release criteria. The MARSSIM procedures were proved to be flexible, scientifically rigorous and cost effective for final status survey of decommissioning site and building. For the effective plan for the final status survey of the UCP site and its implementation, KAERI and its the regulation body are continuously discussing way to ensure the validation of the final status survey.

  2. Development on treatment technology using cyclon separator in an uranium concentration plant

    Energy Technology Data Exchange (ETDEWEB)

    Iko, Shuji; Endo, Yuji [Japan Nuclear Cycle Development Inst., Kamisaibara, Okayama (Japan). Ningyo Toge Environmental engineering Center

    2001-01-01

    The Ningyo Toge Environmental Engineering Center of the Japan Nuclear Cycle Development Institute has accumulated steadily a lot of results on technical development of uranium concentration using cyclon separator for about 20 years since 1979. And, as a proto-type plant stated to fully operate in 1989 has reflected a lot of results through its construction and operation to a commercial plant at Rokkasho-mura, Aomori prefecture, it is decided to finish operation of the cyclon separator by 2000 fiscal year and transfer of uranium concentration technologies to private company also approaches to its finish. Together with finish of the plant operation, the separator becomes to accumulate radioactive wastes, of which volume is estimated to jumpingly increase in future. As treatment of the separator has been investigated till now, it becomes a new evolution of the 'development on treatment technology using cyclon separator' at present. Aims of carrying out the development consist in two points of wide reduction of massively forming radioactive wastes and of disappearance of informations on structure, materials and so on (secret detailed informations) of the separator from a viewpoint of nuclear non-distribution. Here was introduced a treating apparatus constructed at the Ningyo Toge Environmental Engineering Center at an aim of reduction on formation of radioactive wastes, which just started its operation to collect various types of data required for establishment of its aims. (G.K.)

  3. Screening of plant species as ground cover on uranium mill tailings

    International Nuclear Information System (INIS)

    The concept of construction of dams or holding areas for uranium mill tailings is relatively new in India and to date there is only one such facility being maintained by Uranium Corporation of India Limited (UCIL) at Jaduguda in Jharkhand. Due to the residual nature of radionuclides, chiefly uranium and its daughter products, special emphasis is given to the engineering aspects of the mill tailings ponds so as to ensure safety to general public for at least 200 years. Once a mill tailings pond reaches to its full capacity, creation of barrier layers over the mill tailings to prevent seepage of rain water and also erosion of mill tailings due to wind and water are advocated and a number of procedures are followed worldwide. Taking the extraordinary period of public safety to be assured, providing soil covers along with contouring and appropriate slopes over which vegetation is grown is gaining popularity. The vegetation not only reduces the impact of rain water hitting the soil cover, thereby reducing the soil erosion, but also lowers the moisture in the soil cover by extensive evapotranspiration, ensuring long term hydrological separation of the mill tailings underneath. Based on set criteria, applicable to the field scenario of mill tailings, a screening experiment was conducted under pot culture conditions to evaluate the survival and growth of different plant species. The plants after germination and hardening were transplanted into beakers containing mill tailings and periodical measurements on appropriate morphological characteristics such as plant height, length of twiners, number of tillers and number of leaves were recorded and evaluated. Of the twenty species tested in mill tailings, significant differences were noticed in the vigour of growth and several plant species could indeed establish well completing their life cycle including flowering and seed setting. Further, several leguminous species could also produce root nodules. It appears that the

  4. Case-control study of lung cancer among workers at a uranium processing plant

    International Nuclear Information System (INIS)

    The purpose of this case-control study was to investigate the relationship between exposure to radiation resulting from the inhalation of uranium dust and the dust of uranium-bearing compounds and death due to lung cancer. Cases and controls were chosen from a cohort of white male workers employed at one uranium processing plant during World War II. The 330 cases consisted of all lung cancer deaths occurring in the cohort between 1943 and 1973. Level of exposure to radiation and other potential workplace carcinogens was determined for each worker using process manuals, industrial hygiene reports, air monitoring data and individual work histories. Smoking status and information regarding medical variables was determined from employee medical records. Cumulative radiation lung dose among study population members ranged from 0 to 75 rads. Data were analyzed using Mantel-Haenszel stratified analysis and logistic regression. Relative risk was found to increase with increasing level of lung dose exposure even after controlling for age, smoking status and other workplace exposures, but only for those who were over the age of 44 when first exposed. A statistically significant excess in risk was found for men in this hire age group with a cumulative lung dose of 20 rads or more. The risk associated with the overall work environment was also investigated using a summary measure of total workplace exposure called chemical rank. A similar relationship existed between chemical rank and lung cancer to that found for cumulative lung dose and lung cancer

  5. Mill tailings disposal and environmental monitoring at the Ningyo-Toge uranium processing pilot plant

    International Nuclear Information System (INIS)

    The tailings from the uranium processing pilot plant with a maximum ore processing capacity of 50 t/d are transferred to a tailings dam. The overflow from the dam is chemically treated and through settling ponds, sand filters to be discharged into a river. The concentrations of U, 226Ra, pH, S.S., COD, Fe, Mn, Cl and F were monitored periodically and they were all below the control values. The results of monitoring on the river bed and rice paddy soil showed no signs of accumulation of U and 226Ra in it

  6. BIO-MONITORING FOR URANIUM USING STREAM-SIDE TERRESTRIAL PLANTS AND MACROPHYTES

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, E.; Duff, M.; Hicks, T.; Coughlin, D.; Hicks, R.; Dixon, E.

    2012-01-12

    This study evaluated the abilities of various plant species to act as bio-monitors for environmental uranium (U) contamination. Vegetation and soil samples were collected from a U processing facility. The water-way fed from facility storm and processing effluents was the focal sample site as it represented a primary U transport mechanism. Soils and sediments from areas exposed to contamination possessed U concentrations that averaged 630 mg U kg{sup -1}. Aquatic mosses proved to be exceptional accumulators of U with dry weight (dw) concentrations measuring as high as 12500 mg U kg{sup -1} (approximately 1% of the dw mass was attributable to U). The macrophytes (Phragmites communis, Scripus fontinalis and Sagittaria latifolia) were also effective accumulators of U. In general, plant roots possessed higher concentrations of U than associated upper portions of plants. For terrestrial plants, the roots of Impatiens capensis had the highest observed levels of U accumulation (1030 mg kg{sup -1}), followed by the roots of Cyperus esculentus and Solidago speciosa. The concentration ratio (CR) characterized dry weight (dw) vegetative U levels relative to that in associated dw soil. The plant species that accumulated U at levels in excess of that found in the soil were: P. communis root (CR, 17.4), I. capensis root (CR, 3.1) and S. fontinalis whole plant (CR, 1.4). Seven of the highest ten CR values were found in the roots. Correlations with concentrations of other metals with U were performed, which revealed that U concentrations in the plant were strongly correlated with nickel (Ni) concentrations (correlation: 0.992; r-squared: 0.984). Uranium in plant tissue was also strongly correlated with strontium (Sr) (correlation: 0.948; r-squared: 0.899). Strontium is chemically and physically similar to calcium (Ca) and magnesium (Mg), which were also positively-correlated with U. The correlation with U and these plant nutrient minerals, including iron (Fe), suggests that active

  7. Accumulation of uranium by aquatic plants in field conditions: Prospects for phytoremediation

    International Nuclear Information System (INIS)

    A study was undertaken to determine Uranium concentrations in water and aquatic plants in the uraniferous region of Beiras, Central Portugal. Samples were collected from running water (n = 200) at places where aquatic species were observed. Plant samples were collected from 28 species of submerged, free-floating and rooted emergent plants including 2 bryophytes and 1 pteridophyte. Uranium concentrations in surface waters ranged from 0.23 to 1217 μg L−1. The aquatic plant species studied, including several previously untested species, exhibited the ability to accumulate U in concentrations many times that of the ambient water. In general submerged plants exhibited higher U content followed by rooted emergent and free floating species. The highest U concentrations were observed in the bryophyte Fontinalis antipyretica (up to 4979 mg kg−1) followed by Callitriche stagnalis (1963 mg kg−1), Callitriche hamulata (379 mg kg−1), Ranunculus peltatus subsp. saniculifolius (243 mg kg−1), Callitriche lusitanica (218 mg kg−1), and Ranunculus trichophyllus (65.8 mg kg−1). In two out of three rooted emergent species U seemed to be preferentially partitioned in rhizome/roots with highest rhizome U content recorded in Typha latifolia (380 mg kg−1). Among the free-floating species, the highest U content (42.5 mg kg−1) was seen in Lemna minor. The bryophyte F. antipyretica and Callitrichaceae members seem to be promising candidates for the development of phytofiltration methodologies based on U accumulation, abundance and biomass production. - Highlights: • Exploration of U contamination extent in uraniferous province of Central Portugal • A group of previously untested species with the ability to accumulate U was assessed • U accumulation patterns in the species indicate their potential in bioindication and phytoremediation of U-contaminated water

  8. 226Ra bioavailability to plants at the Urgeiriça uranium mill tailings site.

    Science.gov (United States)

    Madruga, M J; Brogueira, A; Alberto, G; Cardoso, F

    2001-01-01

    Large amounts of solid wastes (tailings) resulting from the exploitation and treatment of uranium ore at the Urgeiriça mine (north of Portugal) have been accumulated in dams (tailing ponds). To reduce the dispersion of natural radionuclides into the environment, some dams were revegetated with eucalyptus (Eucalyptus globolus) and pines (Pinus pinea). Besides these plants, some shrubs (Cytisus spp.) are growing in some of the dams. The objective of this study is to determine the 226Ra bioavailability from uranium mill tailings by quantifying the total and available fraction of radium in the tailings and to estimate its transfer to plants growing on the tailing piles. Plant and tailing samples were randomly collected and the activity concentration of 226Ra in plants (aerial part and roots) and tailings was measured by gamma-spectrometry. The exchangeable fraction of radium in tailings was quantified using one single step extraction with 1 mol dm-3 ammonium acetate (pH = 7) or 1 mol dm-3 calcium chloride solutions. The results obtained for 226Ra uptake by plants show that 226Ra concentration ratios for eucalyptus and pines decrease at low 226Ra concentrations in the tailings and appear relatively constant at higher radium concentrations. For shrubs, the concentration ratios increase at higher 226Ra solid waste concentrations approaching a saturation value. Percentage values of 16.0 +/- 8.3 and 12.9 +/- 8.9, for the fraction of radium extracted from the tailings, using 1 mol dm-3 ammonium acetate or calcium chloride solutions, respectively, were obtained. The 226Ra concentration ratios determined on the basis of exchangeable radium are one order of magnitude higher than those based on total radium. It can be concluded that, at a 95% confidence level, more consistent 226Ra concentration ratios were obtained when calculated on the basis of available radium than when total radium was considered, for all the dams. PMID:11379070

  9. Accumulation of uranium by aquatic plants in field conditions: Prospects for phytoremediation

    Energy Technology Data Exchange (ETDEWEB)

    Favas, Paulo J.C., E-mail: pjcf@utad.pt [School of Life Sciences and the Environment, University of Trás-os-Montes e Alto Douro, 5001-801 Vila Real (Portugal); IMAR-CMA Marine and Environmental Research Centre, Faculty of Sciences and Technology, University of Coimbra, 3001-401 Coimbra (Portugal); Pratas, João [Department of Earth Sciences, Faculty of Sciences and Technology, University of Coimbra, 3001-401 Coimbra (Portugal); IMAR-CMA Marine and Environmental Research Centre, Faculty of Sciences and Technology, University of Coimbra, 3001-401 Coimbra (Portugal); Varun, Mayank; D' Souza, Rohan; Paul, Manoj S. [Department of Botany, St. John' s College, Agra 282 002 (India)

    2014-02-01

    A study was undertaken to determine Uranium concentrations in water and aquatic plants in the uraniferous region of Beiras, Central Portugal. Samples were collected from running water (n = 200) at places where aquatic species were observed. Plant samples were collected from 28 species of submerged, free-floating and rooted emergent plants including 2 bryophytes and 1 pteridophyte. Uranium concentrations in surface waters ranged from 0.23 to 1217 μg L{sup −1}. The aquatic plant species studied, including several previously untested species, exhibited the ability to accumulate U in concentrations many times that of the ambient water. In general submerged plants exhibited higher U content followed by rooted emergent and free floating species. The highest U concentrations were observed in the bryophyte Fontinalis antipyretica (up to 4979 mg kg{sup −1}) followed by Callitriche stagnalis (1963 mg kg{sup −1}), Callitriche hamulata (379 mg kg{sup −1}), Ranunculus peltatus subsp. saniculifolius (243 mg kg{sup −1}), Callitriche lusitanica (218 mg kg{sup −1}), and Ranunculus trichophyllus (65.8 mg kg{sup −1}). In two out of three rooted emergent species U seemed to be preferentially partitioned in rhizome/roots with highest rhizome U content recorded in Typha latifolia (380 mg kg{sup −1}). Among the free-floating species, the highest U content (42.5 mg kg{sup −1}) was seen in Lemna minor. The bryophyte F. antipyretica and Callitrichaceae members seem to be promising candidates for the development of phytofiltration methodologies based on U accumulation, abundance and biomass production. - Highlights: • Exploration of U contamination extent in uraniferous province of Central Portugal • A group of previously untested species with the ability to accumulate U was assessed • U accumulation patterns in the species indicate their potential in bioindication and phytoremediation of U-contaminated water.

  10. The New Generation of Uranium In Situ Recovery Facilities: Design Improvements Should Reduce Radiological Impacts Relative to First Generation Uranium Solution Mining Plants

    International Nuclear Information System (INIS)

    In the last few years, there has been a significant increase in the demand for Uranium as historical inventories have been consumed and new reactor orders are being placed. Numerous mineralized properties around the world are being evaluated for Uranium recovery and new mining / milling projects are being evaluated and developed. Ore bodies which are considered uneconomical to mine by conventional methods such as tunneling or open pits, can be candidates for non-conventional recovery techniques, involving considerably less capital expenditure. Technologies such as Uranium In Situ Leaching / In Situ Recovery (ISL / ISR - also referred to as 'solution mining'), have enabled commercial scale mining and milling of relatively small ore pockets of lower grade, and are expected to make a significant contribution to overall world wide uranium supplies over the next ten years. Commercial size solution mining production facilities have operated in the US since the mid 1970's. However, current designs are expected to result in less radiological wastes and emissions relative to these 'first' generation plants (which were designed, constructed and operated through the 1980's). These early designs typically used alkaline leach chemistries in situ including use of ammonium carbonate which resulted in groundwater restoration challenges, open to air recovery vessels and high temperature calcining systems for final product drying vs the 'zero emissions' vacuum dryers as typically used today. Improved containment, automation and instrumentation control and use of vacuum dryers in the design of current generation plants are expected to reduce production of secondary waste byproduct material, reduce Radon emissions and reduce potential for employee exposure to uranium concentrate aerosols at the back end of the milling process. In Situ Recovery in the U.S. typically involves the circulation of groundwater, fortified with oxidizing (gaseous oxygen e.g) and complexing agents (carbon

  11. Soil-to-plant transfer of uranium and its distribution between plant parts in four boreal forest species

    International Nuclear Information System (INIS)

    Uranium (U) can be released to the environment through the entire nuclear fuel cycle. U uptake by plants is an important process for possible adverse effects in ecosystems. The soil-to-plant transfer of natural U and its distribution across plant parts were investigated in May lily (Maianthemum bifolium), narrow buckler fern (Dryopteris carthusiana), rowan (Sorbus aucuparia) and Norway spruce (Picea abies). Concentration ratios (CR) between plant and soil were calculated. The CRs for roots were higher than those for the above-ground parts of the plants. Soil pH was the only soil parameter showing an effect on CRs. No significant differences were noticed between species. The CRs observed were consistent with those reported previously in other forest types. The pooled values of 0.06 for roots and 0.005 for stems/petioles and leaves/needles can be considered as good estimates of CR values to be used in modelling the U uptake in boreal forest species. (orig.)

  12. Functional design criteria for the 242-A evaporator and PUREX [Plutonium-Uranium Extraction] Plant condensate interim retention basin

    International Nuclear Information System (INIS)

    This document contains the functional design criteria for a 26- million-gallon retention basin and 10 million gallons of temporary storage tanks. The basin and tanks will be used to store 242-A Evaporator process condensate, the Plutonium-Uranium Extraction (PUREX) Plant process distillate discharge stream, and the PUREX Plant ammonia scrubber distillate stream. Completion of the project will allow both the 242-A Evaporator and the PUREX Plant to restart. 4 refs

  13. Literature review: Phytoaccumulation of chromium, uranium, and plutonium in plant systems

    Energy Technology Data Exchange (ETDEWEB)

    Hossner, L.R.; Loeppert, R.H.; Newton, R.J. [Texas A& M Univ., College Station, TX (United States); Szaniszlo, P.J. [Univ. of Texas, Austin, TX (United States)

    1998-05-01

    Phytoremediation is an integrated multidisciplinary approach to the cleanup of contaminated soils, which combines the disciplines of plant physiology, soil chemistry, and soil microbiology. Metal hyperaccumulator plants are attracting increasing attention because of their potential application in decontamination of metal-polluted soils. Traditional engineering technologies may be too expensive for the remediation of most sites. Removal of metals from these soils using accumulator plants is the goal of phytoremediation. The emphasis of this review has been placed on chromium (Cr), plutonium (Pu), and uranium (U). With the exception of Cr, these metals and their decay products exhibit two problems, specifically, radiation dose hazards and their chemical toxicity. The radiation hazard introduces the need for special precautions in reclamation beyond that associated with non-radioactive metals. The uptake of beneficial metals by plants occurs predominantly by way of channels, pores, and transporters in the root plasma membrane. Plants characteristically exhibit a remarkable capacity to absorb what they need and exclude what they don`t need. But most vascular plants absorb toxic and heavy metals through their roots to some extent, though to varying degrees, from negligible to substantial. Sometimes absorption occurs because of the chemical similarity between beneficial and toxic metals. Some plants utilize exclusion mechanisms, where there is a reduced uptake by the roots or a restricted transport of the metal from root to shoot. At the other extreme, hyperaccumulator plants absorb and concentrate metals in both roots and shoots. Some plant species endemic to metalliferous soils accumulate metals in percent concentrations in the leaf dry matter.

  14. Natural phenomena hazards evaluation of equipment and piping of Gaseous Diffusion Plant Uranium Enrichment Facility

    International Nuclear Information System (INIS)

    In support of the Gaseous Diffusion Plant Safety Analysis Report Upgrade program (GDP SARUP), a natural phenomena hazards evaluation was performed for the main process equipment and piping in the uranium enrichment buildings at Paducah and Portsmouth gaseous diffusion plants. In order to reduce the cost of rigorous analyses, the evaluation methodology utilized a graded approach based on an experience data base collected by SQUG/EPRI that contains information on the performance of industrial equipment and piping during past earthquakes. This method consisted of a screening walkthrough of the facility in combination with the use of engineering judgment and simple calculations. By using these screenings combined with evaluations that contain decreasing conservatism, reductions in the time and cost of the analyses were significant. A team of experienced seismic engineers who were trained in the use of the DOE SQUG/EPRI Walkdown Screening Material was essential to the success of this natural phenomena hazards evaluation

  15. Some design and operating aspects of the Ranger uranium mine treatment plant

    International Nuclear Information System (INIS)

    Environmental considerations were key factors in the design of the Ranger Uranium Mines treatment plant. The mine is located adjacent to the Kakadu National Park and has an average rainfall of 1.6m per annum. No contaminated water or liquid effluents are to be released from the project area and thus water management is a key design and operating fact. Particulate and gas emission criteria influenced design as did occupational hygiene factors (dust, radon, housekeeping, maintenance access). Equipment selection and engineering standards were conservative and resulted in the plant attaining design performance in less than three months from the date of commissioning. A number of mechanical and operational problems were experienced. However, none of these problems have had a significant effect on production

  16. Relationship Between 210Pb Concentrations in Solid Wastes and Plants from Uranium Mill Tailings

    International Nuclear Information System (INIS)

    Full text: The exploitation and treatment of uranium ore at the Urgeirica mine (north of Portugal) have led to the accumulation of large amounts of soild wastes (mill tailings) in dams (tailing ponds). These solid wastes containing natural radionuclides could be dispersed by the action of atmospheric agents and contaminate the environment. To minimize the dispersion of these radionuclides into the environment the dams were revegetated with pines (Pinus pinea) and eucalyptes (Eucalyptus globolus). The objective of this study is to know the 210Pb behaviour in what concerns its transfer from the uranium mill tailings to these plants, through the analysis of relationships between 210Pb concentrations in the solid wastes and the plants. Solid wastes and plant samples were randomly collected at the dams and the 210Pb activity concentration in solid wastes and plant (aerial part and roots) samples were determined by gamma spectrometry. The results obtained for pines show a good correlation between 210Pb concentrations in the solid wastes and roots. No correlation was found to 210Pb concentrations in the solid wastes and needles. The 210Pb concentration data for eucalyptes show a quite good correlation between 210Pb concentrations in the solid wastes and leaves. Concentration ratio data, solid wastes/roots and solid wastes/needles for pines are on the same order of magnitude. The 210Pb uptake by pines (roots and needles) and eucalyptes (leaves) show that 210Pb concentration ratios decrease at low 210Pb concentrations in the solid wastes and appear relatively constant at higher 210Pb concentrations in the solid wastes. Data presented for 210Pb in this paper, will be compared with those obtained for 226Ra on the same samples. (author)

  17. Uptake of uranium, thorium and radium isotopes by plants growing in dam impoundment Tasotkel and the Lower Shu region (Kazakhstan)

    Energy Technology Data Exchange (ETDEWEB)

    Matveyeva, Ilona; Burkitbayev, Mukhambetkali [al-Farabi Kazakh National University, Almaty (Kazakhstan). Faculty of Chemistry and Chemical Technology; Jacimovic, Radojko [Jozef Stefan Institute, Ljubljana (Slovenia). Dept. of Environmental Sciences; Planinsek, Petra; Smodis, Borut [Jozef Stefan Institute, Ljubljana (Slovenia). Dept. of Environmental Sciences; Jozef Stefan International Postgraduate School, Ljubljana (Slovenia)

    2016-04-01

    The activity concentrations of isotopes of uranium, thorium and radium-226 in dominant species of plants (Xantium strumarium, Phragmites communis, Artemisia nitrosa and Artemisia serotina) growing on the territories contaminated by uranium industry of Kazakhstan (close to dam impoundment Tasotkel and the Lower Shu region) are presented. The obtained data showed the significant variations of activity concentrations of isotopes of uranium, thorium and radium-226 in above ground parts. The concentrations of most of the investigated radionuclides in the root system are higher than in the aboveground parts; it can be explained by root barrier. It was found that the highest root barrier has Xantium strumarium, especially for uranium isotopes. The concentration ratios of radionuclides were calculated, and as the result it was found that the highest accumulation ability in the investigated region has Artemisia serotina.

  18. Uptake of uranium, thorium and radium isotopes by plants growing in dam impoundment Tasotkel and the Lower Shu region (Kazakhstan)

    International Nuclear Information System (INIS)

    The activity concentrations of isotopes of uranium, thorium and radium-226 in dominant species of plants (Xantium strumarium, Phragmites communis, Artemisia nitrosa and Artemisia serotina) growing on the territories contaminated by uranium industry of Kazakhstan (close to dam impoundment Tasotkel and the Lower Shu region) are presented. The obtained data showed the significant variations of activity concentrations of isotopes of uranium, thorium and radium-226 in above ground parts. The concentrations of most of the investigated radionuclides in the root system are higher than in the aboveground parts; it can be explained by root barrier. It was found that the highest root barrier has Xantium strumarium, especially for uranium isotopes. The concentration ratios of radionuclides were calculated, and as the result it was found that the highest accumulation ability in the investigated region has Artemisia serotina.

  19. History of Uranium-233(233U)Processing at the Rocky Flats Plant. In support of the RFETS Acceptable Knowledge Program

    International Nuclear Information System (INIS)

    This report documents the processing of Uranium-233 at the Rocky Flats Plant (Rocky Flats Environmental Technology Site). The information may be used to meet Waste Isolation Pilot Plant (WIPP) Waste Acceptance Criteria (WAC)and for determining potential Uranium-233 content in applicable residue waste streams

  20. Some recent improvements in a uranium processing pilot-plant at the Ningyo-toge mine

    International Nuclear Information System (INIS)

    Since 1964 the uranium processing plant at the Ningyo-toge mine has been modified and extended. In 1970 an ammonium diuranate (ADU) producing process was added to the plant, and a pilot plant with an ore-processing capacity of 50t/d was brought into operation. As a result of this operation the process which produces high-purity ADU was confirmed. An electrolytic reduction plant for the pilot operation was constructed by the Asahi Chemical Industry Co. in 1972. Experiments on the reduction of uranyl chloride solution were carried out with good results. Hydrofluorination facilities were added to the plant in 1974 and experiments on the hydrofluorination of UCl4 started. The experiments also studied the characteristics of hydrated UF4. Preliminary experiments on dehydration from hydrated UF4 were carried out to determine the dehydration conditions and the properties of the UF4 in the laboratory at the Tokai Works, PNC. The results of these dehydration experiments and UF4 conversion tests were excellent. (author)

  1. Experience with in-operation physical inventory-taking (PIT) in Japan's Uranium Enrichment Pilot Plant

    International Nuclear Information System (INIS)

    For a stable energy supply in Japan it is necessary to produce domestically a reasonable amount of low enriched uranium. This led to the construction of the first-stage gas-centrifuge cascade (OP-1) in the Uranium Enrichment Pilot Plant, Ningyo Toge Works, PNC, in July 1979, followed by the second-stage cascade (OP-2) in October 1981. Although the pilot plant involves a variety of sensitive information, it is essential to provide it with adequate safeguards measures and physical protection systems to follow the Nuclear Non-proliferation Treaty. This paper describes the development of materials accountancy in the pilot plant, stressing the in-operation PIT, i.e. the physical inventory-taking while the plant is in operation. According to INFCIRC-153, all nuclear material handling facilities must close their material balances at least once a year. For closing material balances, the temporary suspension of facility operations is required, but for the economical production of low enriched uranium, continuous operation for an extended period of time is essential. Thus, it is necessary to develop in-operation PIT. Therefore, PNC tentatively carried out in-operation PIT at the end of 1981 by using OP-1. The simultaneous changeover in the feed, product and tail lines, which was necessary for conducting the in-operation PIT, took only three minutes. The material balance period for this PIT started at the beginning of 1981 and continued to the end of that year. The material balance areas (MBA) consisted of the storage MBA (inventory KMP-A and B) and the process MBA (inventory KMP-C and F). After measuring weights, volumes, temperatures, pressures etc., the inventories of the storage and process MBAs were calculated, followed by evaluation of the amounts of MUFs and σsub(MUF). As a result, the value of MUF per annual throughput was 0.05% which is far lower than the expected MUF value of 0.2% specified by the IAEA

  2. Perspectives of Siberian chemical plant in increasing volumes of uranium concentrates recycling

    OpenAIRE

    Lazarchuk, V. V.; Shikerun, T. G.; Ryabov, A. S.; Shamin, V. I.; Zhiganov, A. N.

    2007-01-01

    The purification technology of uranium concentrate of natural isotopic composition developed at Siberian chemical enterprise is basically universal, allows recycling uranium concentrates with different content of impurities and obtaining uranium nitrate solutions corresponding by quality to the international standards requirements to uranium hexafluoride preparation for isotopes ASTM C 787-03 separation and to ceramic fuel ASTM C 788-02 preparation. Uranium reserves in Russia and abroad were ...

  3. Pilot uranium lysimeter studies at the Oak Ridge Y-12 plant

    International Nuclear Information System (INIS)

    A field lysimeter test facility has been constructed at the Oak Ridge Y-12 plant to evaluate land burial of wastes containing depleted uranium. The principal objective in the construction of such a facility is to provide a means for monitoring waste leachate characteristics over time, in particular uranium concentrations in leachate. The design of the field lysimeter test facility allows, via the portals along the side walls of the lysimeter, the collection of leachate as a function of depth in the lysimeter. The methodology to collect leachate from within the field lysimeter has not been clearly defined. Thus, before wastes were loaded into the field lysimeter facility, a pilot lysimeter study was initiated to test several design concepts for the collection of in situ leachate. The primary objective of this pilot study was to demonstrate the feasibility and quality assurance of proposed instrumentation used to monitor leachate generation and characteristics in the full-scale field lysimeter. Secondary objectives included gaining experience in the handling/packing of wastes, installation/operation of the leachate collection devices, and waste leachate characterization

  4. Assessment of enriched uranium storage safety issues at the Oak Ridge Y-12 Plant

    International Nuclear Information System (INIS)

    This document is an assessment of the technical safety issues pertaining to the storage of EU at the Oak Ridge Y-12 Plant. The purpose of the assessment is to serve as the basis for defining the technical standards for storage of EU at Y-12. A formal assessment of the Y-12 materials acceptance criteria for EU is currently being conducted by a task force cochaired by B. G. Eddy of DOE Oak Ridge Operations and S. 0. Cox of Y-12 Defense Programs. The mission of this technical assessment for storage is obviously dependent on results of the acceptance assessment. Clearly, the two efforts require coordination to avoid inconsistencies. In addition, both these Assessments must be consistent with the Environmental Assessment for EU storage at Y-12.1 Both the Storage Assessment and the Criteria for Acceptance must take cognizance of the fact that a portion of the EU to be submitted for storage in the future is expected to be derived from foreign sources and to include previously irradiated uranium containing significant levels of transuranics, radioactive daughter products, and unstable uranium isotopes that do not occur in the EU stream of the DOE weapons complex. National security considerations may dictate that these materials be accepted despite the fact that they fail to conform to the Acceptance Criteria. This document will attempt to address the complexities inherent in this situation

  5. Assessment of enriched uranium storage safety issues at the Oak Ridge Y-12 Plant

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    This document is an assessment of the technical safety issues pertaining to the storage of EU at the Oak Ridge Y-12 Plant. The purpose of the assessment is to serve as the basis for defining the technical standards for storage of EU at Y-12. A formal assessment of the Y-12 materials acceptance criteria for EU is currently being conducted by a task force cochaired by B. G. Eddy of DOE Oak Ridge Operations and S. 0. Cox of Y-12 Defense Programs. The mission of this technical assessment for storage is obviously dependent on results of the acceptance assessment. Clearly, the two efforts require coordination to avoid inconsistencies. In addition, both these Assessments must be consistent with the Environmental Assessment for EU storage at Y-12.1 Both the Storage Assessment and the Criteria for Acceptance must take cognizance of the fact that a portion of the EU to be submitted for storage in the future is expected to be derived from foreign sources and to include previously irradiated uranium containing significant levels of transuranics, radioactive daughter products, and unstable uranium isotopes that do not occur in the EU stream of the DOE weapons complex. National security considerations may dictate that these materials be accepted despite the fact that they fail to conform to the Acceptance Criteria. This document will attempt to address the complexities inherent in this situation.

  6. Pilot uranium lysimeter studies at the Oak Ridge Y-12 plant

    Energy Technology Data Exchange (ETDEWEB)

    Francis, C.W.; Hyder, L.K.; Howard, S.C.; Cline, J.E.; Clapp, R.B.

    1993-08-01

    A field lysimeter test facility has been constructed at the Oak Ridge Y-12 plant to evaluate land burial of wastes containing depleted uranium. The principal objective in the construction of such a facility is to provide a means for monitoring waste leachate characteristics over time, in particular uranium concentrations in leachate. The design of the field lysimeter test facility allows, via the portals along the side walls of the lysimeter, the collection of leachate as a function of depth in the lysimeter. The methodology to collect leachate from within the field lysimeter has not been clearly defined. Thus, before wastes were loaded into the field lysimeter facility, a pilot lysimeter study was initiated to test several design concepts for the collection of in situ leachate. The primary objective of this pilot study was to demonstrate the feasibility and quality assurance of proposed instrumentation used to monitor leachate generation and characteristics in the full-scale field lysimeter. Secondary objectives included gaining experience in the handling/packing of wastes, installation/operation of the leachate collection devices, and waste leachate characterization

  7. Effects of phosphorus fertilization on the availability and uptake of uranium and nutrients by plants grown on soil derived from uranium mining debris

    International Nuclear Information System (INIS)

    Subterranean clover and barley were grown on a soil derived from uranium mining debris and fertilized with phosphate as a U immobilizing additive for in situ remediation. We investigated the beneficial effect of P fertilization in the range 0-500 mg P kg-1 soil in terms of U extractability, plant biomass production and U uptake. Increasing P in the mining debris caused a significant decrease of the water-soluble U and NH4-Ac extractable U at pH 7 and 5. For both plant species, P fertilization considerably increased root and shoot dry matter up to a maximum observed for soil receiving 100 mg P kg-1 while the soil-to-plant transfer of U was regularly decreased by increasing P content in soil. These observations show that P fertilization represents an in situ practical option to facilitate the revegetation of U-mining heaps and to reduce the risks of biota exposure to U contamination. - Phosphate addition to soil derived from uranium mining debris may decrease U mobility and bioavailability to plant

  8. Concentrations of uranium and 235U/238U ratios in soil and plant samples collected around the uranium conversion building in the JCO campus

    International Nuclear Information System (INIS)

    In order to assess possible contamination by U in the JCO campus following the criticality accident, 10 soil samples and 15 plant samples were collected around the uranium conversion building. Uranium concentrations and isotopic compositions (235U/238U ratio) were determined by ICP-MS. Concentrations of Th in soil were also determined for comparison. Concentrations of U in soils were comparable to the U values for common Japanese soils. However, the U/Th ratios for these soil samples were markedly higher than the control value, suggesting possible contamination by U. The 235U/238U atom ratios in soil and plant samples were notably higher than the natural ratio, 0.00725. The highest values, 0.0162 for soil and 0.0193 for plant, were found in samples collected near the conversion building. However, a relatively high ratio was observed at a site more than 50 m from the building, indicating that enriched U may have been released not only from the conversion building but also from other unknown sources. 235U/238U atom ratios were in general higher in plants than in soils collected at the same points

  9. Investigation report on criticality accident at the Uranium Processing Plant of the JCO, Ltd

    International Nuclear Information System (INIS)

    This report is a summarized one of investigation results on a criticality accident at the Uranium Processing Plant of the JCO, Ltd., carried out by the Nuclear Safety Investigation Special Group (SISG) of the Atomic Energy Society of Japan (AESJ). AESJ published a statement of the president on this accident on October 8, 1999, and decided to perform its investigation under SISG. SISG carried out some questionnaires for new trials together with conventional lectures of the well-informed. This report contains six chapters on critical safety and accident, process of the accident and elucidation of its facts, cause analysis and picking-out on problems, questionnaires on improvement proposal', questionnaires on 'duty of AESJ7, and future efforts on nuclear safety culture. At the last chapter, SISG discussed about some items on re-occurrence protection of the nuclear accident. (G.K.)

  10. Evaluation of terrestrial plants extracts for uranium sorption and characterization of potent phytoconstituents.

    Science.gov (United States)

    Sharma, Sunita; Singh, Bikram; Thulasidas, S K; Kulkarni, Madhuri J; Natarajan, V; Manchanda, Vijay K

    2016-01-01

    Sorption capacity of four plants (Funaria hygrometrica, Musa acuminata, Brassica juncea and Helianthus annuus) extracts/fractions for uranium, a radionuclide was investigated by EDXRF and tracer studies. The maximum sorption capacity, i.e., 100% (complete sorption) was observed in case of Musa acuminata extract and fractions. Carbohydrate, proteins, phenolics and flavonoids contents in the active fraction (having maximum sorption capacity) were also determined. Further purification of the most active fraction provided three pure molecules, mannitol, sorbitol and oxo-linked potassium oxalate. The characterization of isolated molecules was achieved by using FTIR, NMR, GC-MS, MS-MS, and by single crystal-XRD analysis. Of three molecules, oxo-linked potassium oxalate was observed to have 100% sorption activity. Possible binding mechanism of active molecule with the uranyl cation has been purposed. PMID:25946322

  11. The New Generation of Uranium In Situ Recovery Facilities: Design Improvements should Reduce Radiological Impacts Relative to First Generation Uranium Solution Mining Plants

    International Nuclear Information System (INIS)

    In the last few years, there has been a significant increase in the demand for Uranium as historical inventories have been consumed and new reactor orders are being placed. Numerous mineralized properties around the world are being evaluated for Uranium recovery and new mining / milling projects are being evaluated and developed. Ore bodies which are considered uneconomical to mine by conventional methods such as tunnelling or open pits, can be candidates for non-conventional recovery techniques, involving considerably less capital expenditure. Technologies such as Uranium In Situ Leaching/In Situ Recovery (ISL/ISR - also referred to as 'solution mining'), have enabled commercial scale mining and milling of relatively small ore pockets of lower grade, and are expected to make a significant contribution to overall world wide uranium supplies over the next ten years. Commercial size solution mining production facilities have operated in the US since the late 1960s. However, current designs are expected to result in less radiological wastes and emissions relative to these 'first' generation plants (which were designed, constructed and operated through the 1980s) which typically used alkaline leach chemistries in situ, open to air recovery vessels and high temperature calcining systems for final product drying. Improved containment, automation and instrumentation control and use of vacuum dryers in the design of current generation plants are expected to reduce production of secondary waste byproduct material, reduce Radon emissions and reduce potential for employee exposure to uranium concentrate aerosols at the back end of the milling process. In Situ Recovery involves the circulation of groundwater, fortified with oxidizing and complexing agents into an ore body, solubilizing the uranium in situ, and then pumping the solutions to the surface where they are fed to a processing plant (mill). Processing involves ion exchange and may also include precipitation, drying or

  12. Issues and recommendations related to replacement of CFC-114 at the uranium enrichment gaseous diffusion plant

    International Nuclear Information System (INIS)

    The operating uranium enrichment gaseous diffusion plants (GDPs) in Portsmouth, Ohio and Paducah, Kentucky, which are operated for the United States Department for Energy by Martin Marietta Energy Systems (MMES), currently use a chlorofluorocarbon (CFC-114) as the primary process stream coolant. Due to recent legislation embodied in the Clean Air Act, the production of this and other related chlorofluorocarbons (CFCS) are to be phased out with no production occurring after 1995. Since the plants lose approximately 500,000 pounds per year of this process stream coolant through various leaks, the GDPs are faced with the challenge of identifying a replacement coolant that will allow continued operation of the plants. MMES formed the CFC Task Team to identify and solve the various problems associated with identifying and implementing a replacement coolant. This report includes a review of the work performed by the CFC Task Team, and recommendations that were formulated based on this review and upon original work. The topics covered include; identifying a replacement coolant, coolant leak detection and repair efforts, coolant safety concerns, coolant level sensors, regulatory issues, and an analytical decision analysis

  13. Health effects in community residents near a uranium plant at Fernald, Ohio, USA

    International Nuclear Information System (INIS)

    Health outcomes in persons who lived in the area surrounding a U.S. Department of Energy (DOE) uranium processing plant near Fernald, Ohio were evaluated using data of Fernald Medical Monitoring Program (FMMP) participants. Residential history information was used to identify participants who lived in close proximity to the plant (less than 2 miles), in the direction of groundwater runoff (south of the plant), or used a well or cistern as a drinking water source. Standardized prevalence ratios (SPRs) for certain disease endpoints were calculated using U.S. National Health Interview Survey (NHIS) and the National Heath and Nutrition Examination Survey (NHANES) data files for comparison rates. Findings suggest that prior living within the Fernald exposure domain is related to increased prevalence of urinary system disease. Statistically significant elevations of bladder disease (standardized prevalence ratio or SPR = 1.32) and kidney disease (SPR = 2.15), including sub-categories, kidney stones (SPR = 3.98) and chronic nephritis (SPR =2.03) wee noted, as well as increased rates for hematuria and urethral stricture. In regression analyses with adjustment for age and sex, serum creatine levels were increased in those who had lived close to the plant. Increased white blood cell count and hemoglobin levels, and decreased mean corpuscular volume were also found in those living less than 2 miles from the plant. Those who used a well or cistern for drinking water were found to have increased urinary microalbumin, red blood cell count and hematocrit. These preliminary findings will provide the basis for future hypothesis testing incorporating important determinants of exposure not included in this study, such as duration and calendar year of exposure, location relevant to prevailing wind direction, and age at exposure. (author)

  14. Uranium and thorium nuclides series determined in medicinal plants commonly used in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Silva, P.; Francisconi, L.; Damatto, S. [IPEN/CNEN-SP, Sao Paulo (Brazil)

    2014-07-01

    In recent years the study of medicinal plants has become the focus of ever more extensive research all over the world due to their diversity and potential as source of medicinal products. According to the World Health Organization approximately 80% of world population makes use of medicinal herbs due to their believed therapeutic action. Besides being used as medicine, medicinal plants are also largely used as dietary supplements. The presence of radionuclides in plants constitutes one of the main pathways for their transfer to man. The amount of radioactive nuclides from U and Th series in edible vegetables are relatively well known since they have been the main concern of research conducted worldwide. Medicinal plants, on the other hand, have been neglected in these studies, possibly because the ingestion of radioactive material through their consumption has not been recognized or was considered insignificant. The objective of the present study was to determine the content of natural radionuclides from {sup 238}U and {sup 232}Th series in 25 species of medicinal plants used in Brazil, both as medicine and as dietary supplement. The medicinal plant samples were obtained in specialized pharmacies and drugstores. The raw plant and their extracts, produced as recommended by the National Agency for Sanitary Vigilance, were analyzed by Instrumental Neutron Activation Analyses for the determination of U and Th and by Total Alpha and Beta Counting after Radiochemical Separation for determination of {sup 226}Ra, {sup 228}Ra and {sup 210}Pb. In the raw plants the activity concentrations varied from 0,08 Bq kg{sup -1} to 8,0 Bq kg{sup -1} for thorium, from < LID to 22 Bq kg{sup -1} for uranium, from 1,8 Bq kg{sup -1} to 12 Bq kg{sup -1} for {sup 226}Ra, from 33 Bq kg{sup -1} to 74 Bq kg{sup -1} for {sup 228}Ra and from 10 Bq kg{sup -1} to 120 Bq kg{sup -1} for {sup 210}Pb. In the extracts, the activity concentrations varied from 9 mBq kg{sup -1} to 137 mBq kg{sup -1} for Th

  15. Uranium and thorium nuclides series determined in medicinal plants commonly used in Brazil

    International Nuclear Information System (INIS)

    In recent years the study of medicinal plants has become the focus of ever more extensive research all over the world due to their diversity and potential as source of medicinal products. According to the World Health Organization approximately 80% of world population makes use of medicinal herbs due to their believed therapeutic action. Besides being used as medicine, medicinal plants are also largely used as dietary supplements. The presence of radionuclides in plants constitutes one of the main pathways for their transfer to man. The amount of radioactive nuclides from U and Th series in edible vegetables are relatively well known since they have been the main concern of research conducted worldwide. Medicinal plants, on the other hand, have been neglected in these studies, possibly because the ingestion of radioactive material through their consumption has not been recognized or was considered insignificant. The objective of the present study was to determine the content of natural radionuclides from 238U and 232Th series in 25 species of medicinal plants used in Brazil, both as medicine and as dietary supplement. The medicinal plant samples were obtained in specialized pharmacies and drugstores. The raw plant and their extracts, produced as recommended by the National Agency for Sanitary Vigilance, were analyzed by Instrumental Neutron Activation Analyses for the determination of U and Th and by Total Alpha and Beta Counting after Radiochemical Separation for determination of 226Ra, 228Ra and 210Pb. In the raw plants the activity concentrations varied from 0,08 Bq kg-1 to 8,0 Bq kg-1 for thorium, from -1 for uranium, from 1,8 Bq kg-1 to 12 Bq kg-1 for 226Ra, from 33 Bq kg-1 to 74 Bq kg-1 for 228Ra and from 10 Bq kg-1 to 120 Bq kg-1 for 210Pb. In the extracts, the activity concentrations varied from 9 mBq kg-1 to 137 mBq kg-1 for Th and 145 mBq kg-1 to 580 mBq kg-1 for U. Document available in abstract form only. (authors)

  16. Palabora Mining Company heavy minerals plant, uranium recovery from copper plant tailings

    International Nuclear Information System (INIS)

    Palabora Mining Company mines more than 100 million t of material annually, and treats 80 000 t per day of ore to produce approximately 120 000 t per year of electrolytic copper and various by-products, including 200 to 250 t of U3O8 as calcine. The latter is recovered in a heavy minerals plant where copper plant tailings carrying very low grades of U3O8 are treated by gravity and chemical processes. The gravity concentration section consists of Reichert cones, tables and a jig. The uranothorianite is upgraded one thousand times before chemical treatment. In the chemical section the heavy minerals concentrate is leached with nitric acid, and the solution is decanted and clarified before being purified by solvent extraction and precipitated as yellow cake. The ADU is calcined producing a 99% U3O8 product

  17. Design of thickener for separation of acidic leach liquor from residual solid particles in Bandar Abas uranium plant

    International Nuclear Information System (INIS)

    Solid-liquid separation is one of the most important sections in mineral processing. High percentage of clay material and fine particles (-200 mesh) cause different problems in separation of uranium leach liquor from the residual solid particles in filtration unit of Bandar Abbas Uranium Plant. The laboratory tests showed that thickener is a suitable device for solid-liquid separation, after leaching unit. For this reason, thickeners were selected for separating of leach liquor from the residual solid particles. For determination of the size and number of thickeners, sedimentation experiments were performed with different Flocculent, Magna floc LT-25was selected as a suitable Flocculent in 75 g/ton. The diameter of thickener was determined to be 13-14 m. In the counter current decantation, the loss percentage of uranium, using 5 thickeners, was selected to be 2.09%

  18. Ecotoxicity evaluation of an amended soil contaminated with uranium and radium using sensitive plants

    Science.gov (United States)

    Abreu, M. M.; Lopes, J.; Magalhães, M. C. F.; Santos, E.

    2012-04-01

    In the centre-north granitic regions of Portugal, during the twenty century radium and uranium were exploited from approximately 60 mines. The closure of all uranium mines, in 2001, raised concerns regarding the possible chemical and radiological effects on the inhabitants health around the mine areas. The main objective of this work was to evaluate the effect of organic amendments and organic hydroxiapatite in the ecotoxicity reduction of agricultural soils contaminated with uranium and radium, by germination and growth tests of two sensitive plants (Lactuca sativa L. and Zea mays L.). Pot experiments, under controlled conditions, were undertaken during two months of incubation at 70% of the soil water-holding capacity. Fluvisol from Urgeiriça region containing large concentration of Utotal (635 mg/kg) and 226Ra (2310 Bq/kg) was used. The soil available fraction, extracted with ammonium acetate, corresponds to 90% and 25% of total concentration of Utotal and 226Ra, respectively. Fine ground bone (FB) and sheep manure (OM) single or mixtures were used as amendments. Four treatments, plus control were carried out in triplicate: (A) soil+40 Mg/ha of FB; (B) soil+70 Mg/ha of OM; (C) soil+70 Mg/ha of OM+40 Mg/ha of FB; (D) soil+70 Mg/ha of OM+20 Mg/ha of FB. After the incubation moist soils were kept at 4-5 °C and subsamples were used for leachates extraction following DIN 38414-S4 method. Maize and lettuce seeds were sown in filter paper moistened with the leachates aqueous solutions and in the moist soil for germination and growth tests. Seedlings after three days of germination were used for growth tests in hydroponic, during seven days, using the leachates. Five seeds per replicate were used. Soil presented: pH(H2O)=5.15, EC=7.3 µS/cm; and Corgnic=12.5 g/kg. After two months of incubation soil pH increased to a maximum of 6.53 in amended samples, and EC showed a dramatic increase when compared to the control (0.398 dS/m), from 1.5 dS/m (treatment-A) to 4.7 d

  19. The taking and verification of a physical inventory in a Low Enriched Uranium Fabrication Plant

    International Nuclear Information System (INIS)

    The paper contains a description of a Low Enriched Uranium Fabrication Plant making fuel elements for Light Water Reactors in Europe and is subject to Euratom and IAEA Safeguards. The process starts from UO-2 powder and ends with the finished elements and has an inventory of about 500 Te. The operators' actions to clean up the plant in order to establish the inventory and to prepare the material in a form so that the inspectors can verify it are described together with an estimate of the cost. A short description of the computerised quasi-real time system of accountancy and control which enables the operator to prepare a list of inventory items from which the sampling plans are made is included. The inspection activities are described in some detail including the basis of the sampling plans used and the selection of the samples. This is followed by the results of the measurements made using a neutron interrogation device for bulk materials and an active neutron coincidence collar for the finished fuel elements. The results and conclusions are surveyed including the calculation of the LEMUF

  20. IBM PC based supervisory control and data acquisition (SCADA) system for uranium metal purification plant

    International Nuclear Information System (INIS)

    Uranium Metal Plant (UMP) is using solvent extraction for production of pure metal nitrate solution. This is achieved with the help of slurry extraction process in which aqueous metal solution is contacted with an immiscible organic phase, controlled by chemical equilibrium. The phase transfer of metal is selectively achieved. Two phases are then allowed to separate by difference in densities. The aqueous and organic solutions are mixed by air lifting and separated in the settler tank. At each stage a large amount of organic stream is recycled from settler to mixer, to avoid formation of stable emulsion due to the presence of solids in aqueous phase. The whole process has considerable hold-up and is very slow. Any change, is responded very slowly and hence very accurate measurement and control of parameters are required. In case of failure or in emergency, if correct and safe actions are not taken, it will cause considerable loss. Thus to achieve higher efficiency in extraction and better yield, a modern automatic control system is important. A compact reliable interactive control system, required to keep the operator updated with all the information regarding plant must be available and the operator can take necessary actions at the earliest. Supervisory control and data acquisition (SCADA) system discussed here relates to the slurry extraction process of UMP. (author). 1 fig

  1. NIRS report of the criticality accident in a uranium conversion test plant in Tokai-mura

    International Nuclear Information System (INIS)

    This report is a detailed account of the roles that National Institute of Radiological Sciences (NIRS) played at the criticality accident in the title, which occurred at around 10:35, on Sep. 30, 1999 and resulted in death of two workers after all, and is published to discharge NIRS responsibilities in regards to the accident. The accident caused many residents concern on their health and rumors had both social and economic consequences. The report involves chapters of detailed outline of the accident; demand for acceptance of the victims and communications until the identification of the criticality'' accident; the acceptance and initial treatment; the exposure dose estimation (based on acute symptoms, on physics, on chromosomal analyses and on neutron-activated dental metals, and detailed analyses for dose distribution); decision made for therapeutic strategies; cooperation with the Network Council for Radiation Emergency and with other medical facilities; the urgent import of medicine; treatment and processes (patients, nursing system and radiation injuries); radiation protection in medical facilities; response to nearby residents of the Plant; international response; press release; Uranium Processing Plant Criticality Accident Investigation Committee and the Health Management Committee organized by the Nuclear Safety Commission; handling of information; and radiation emergency medical preparedness at the NIRS (future issues and prospect). The report is hopefully useful in preventing the occurrence of future accidents. (N.I.)

  2. Criticality accident in uranium fuel processing plant. Questionnaires from Research Committee of Nuclear Safety

    International Nuclear Information System (INIS)

    The Research Committee of Nuclear Safety carried out a research on criticality accident at the JCO plant according to statement of president of the Japan Atomic Energy Society on October 8, 1999, of which results are planned to be summarized by the constitutions shown as follows, for a report on the 'Questionnaires of criticality accident in the Uranium Fuel Processing Plant of the JCO, Inc.': general criticality safety, fuel cycle and the JCO, Inc.; elucidation on progress and fact of accident; cause analysis and problem picking-up; proposals on improvement; and duty of the Society. Among them, on last two items, because of a conclusion to be required for members of the Society at discussions of the Committee, some questionnaires were send to more than 1800 of them on April 5, 2000 with name of chairman of the Committee. As results of the questionnaires contained proposals and opinions on a great numbers of fields, some key-words like words were found on a shape of repeating in most questionnaires. As they were thought to be very important nuclei in these two items, they were further largely classified to use for summarizing proposals and opinions on the questionnaires. This questionnaire had a big characteristic on the duty of the Society in comparison with those in the other organizations. (G.K.)

  3. The report of the criticality accident in a uranium conversion test plant in Tokai-mura

    International Nuclear Information System (INIS)

    The criticality accident in the title occurred at around 10:35, on Sep. 30, 1999, cost the lives of two workers and caused many residents concern on their health. Moreover, rumors had both social and economic consequences. This report is a detailed account of the roles that many individuals and groups in the National Institute of Radiological Sciences (NIRS) performed in a range of the areas, and is published to discharge NIRS responsibilities in regards to the accident. The report involves chapters of detailed outline of the accident; acceptance of the victims and communications until the identification of the ''criticality'' accident; initial treatment; dose estimation (medical, hematological, physical and biological ones and that by dental metals activated by the neutron); decision making for therapeutic strategies; cooperation with the Network Council for Radiation Emergency Medicine and other medical facilities; emergency importation of medical supplies; treatment and progress (nursing system and radiation injuries); protection from radiation in medical facilities; response to nearby residents of the Plant; international response; press release; Uranium Processing Plant Criticality Accident Investigation Committee and the Health Management Committee organized by the Nuclear Safety Commission; handling of information; and radiation emergency medical preparedness at the NIRS (future issues and prospect). The report is hoped to be useful in preventing the occurrence of future accidents. (K.H.)

  4. Uranium dust concentration measured in a conversion plant by aerosol sampling and application for dose calculation

    International Nuclear Information System (INIS)

    COMURHEX is a plant for converting mining concentrates into UF4. The atmosphere in different facilities is monitored daily using aerosol sampling devices (APA) placed in selected locations depending upon the workstations used by the operators. The results, entered every day into a computer program, can be displayed on individual diagrams for each shop. This program allows urinary uranium analyses over a given threshold to be targeted in addition to the systematic analysis performed periodically. In 1996, 23 urinary analyses corresponding to six events exceeding APA guide values were investigated. A direct approximation of systematic contamination from measurement data has recently been described using a deconvolution of individual monitoring results. Uptakes calculated from urine analysis using this method are correlated with the increase of the APA values. This method implies that a specific monitoring protocol is developed by setting up a minimum number of urinary analyses in one year, a maximum interval between two examinations, considering the chemical composition of the components and the urinary level measurements. Internal dosimetry based only on APA values is not sufficient for operational medical monitoring. To reduce the uncertainties in dose calculation, a special program based on bioassay analysis initiated by the APA guide values is better adapted to estimating the internal dose to each worker in the different facilities of the plant. (author)

  5. Uranium hexafluoride packaging tiedown systems overview at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    International Nuclear Information System (INIS)

    The Portsmouth Gaseous Diffusion Plant (PORTS) conducts those operations that are necessary for the production, packaging, and shipment of enriched uranium hexafluoride (UF6). Uranium hexafluoride enriched greater than 1.0 wt percent 235U shall be packaged in accordance with the US Department of Transportation (DOT) regulations of Title 49 CFR Parts 173 and 178, or in US Nuclear Regulatory Commission (NRC) or US Department of Energy (DOE) certified package designs. Concerns have been expressed regarding the various tiedown methods and condition of the trailers being used by some shippers/carriers for international transport of the UF6 cylinders/overpacks. The generally accepted method for securing the overpack during shipment is to bolt its base to the trailer bed. International shipments typically are not made using dedicated trailers, and numerous trailers have been received at PORTS with improperly and potentially dangerously secured overpacks. Also, many trailers have not been loaded at PORTS for international shipment because of mechanical problems, rotten flooring, bald tires, no brakes or brake lights, or broken springs. Because of the concerns about international shipments, the US Department of Energy-Headquarters (DOE-HQ) Office of Nuclear Energy, through DOE-HQ Transportation Management Division, requested Westinghouse Hanford Company to review UF6 packaging tiedown and shipping practices used by PORTS, and where possible and appropriate, provide recommendations for enhancing these practices. Consequently, a team of two individuals from Westinghouse Hanford visited PORTS on March 5 and 6, 1990, for the purpose of conducting this review. The paper provides a brief discussion of the review activities and a summary of the resulting findings and recommendations. A detailed reporting of the review is documented in Reference 4 [Report No. WHC-MR-0233

  6. Uranium hexafluoride packaging tiedown systems overview at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    International Nuclear Information System (INIS)

    The Portsmouth Gaseous Diffusion Plant (PORTS) in Piketon, Ohio, is operated by Martin Marietta Energy Systems, Inc., through the US Department of Energy-Oak Ridge Operations Office (DOE-ORO) for the US Department of Energy-Headquarters, Office of Nuclear Energy. The PORTS conducts those operations that are necessary for the production, packaging, and shipment of enriched uranium hexafluoride (UF6). Uranium hexafluoride enriched greater than 1.0 wt percent 235U shall be packaged in accordance with the US Department of Transportation (DOT) regulations of Title 49 CFR Parts 173 and 178, or in US Nuclear Regulatory Commission (NRC) or US Department of Energy (DOE) certified package designs. Concerns have been expressed regarding the various tiedown methods and condition of the trailers being used by some shippers/carriers for international transport of the UF6 cylinders/overpacks. International shipments typically are not made using dedicated trailers, and numerous trailers have been received at PORTS with improperly and potentially dangerously secured overpacks. Because of the concerns about international shipments, the US Department of Energy-Headquarters (DOE-HQ) Office of Nuclear Energy, through DOE-HQ Transportation Management Division, requested Westinghouse Hanford Company (Westinghouse Hanford) to review UF6 packaging tiedown and shipping practices used by PORTS; and where possible and appropriate, provide recommendations for enhancing these practices. Consequently, a team of two individuals from Westinghouse Hanford visited PORTS on March 5 and 6, 1990, for the purpose of conducting this review. The paper provides a brief discussion of the review activities and a summary of the resulting findings and recommendations

  7. Uranium hexafluoride packaging tiedown systems overview at Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    International Nuclear Information System (INIS)

    The Portsmouth Gaseous Diffusion Plant (PORTS) in Piketon, Ohio operated by Martin Marietta Energy Systems, Inc., through the US Department of Energy-Oak Ridge Operations Office (DOE-ORO) for the US Department of Energy Headquarters, Office of Nuclear Energy. The PORTS conducts those operations that are necessary for the production, packaging, and shipment of enriched uranium hexafluoride (UF6). Uranium hexafluoride enriched greater than 1.0 wt percent 235U shall be packaged in accordance with the US Department of Transportation (DOT) regulations of Title 49 CFR Parts 173 (Reference 1) and 178 (Reference 2), or in US Nuclear Regulatory Commission (NRC) or US Department of Energy (DOE) certified package designs. Concerns have been expressed regarding the various tiedown methods and condition of the trailers being used by some shippers/carriers for international transport of the UF6 cylinders/overpacks (Reference 3). Because of the concerns about international shipments, the US Department of Energy-Headquarters (DOE-HQ) Office of Nuclear Energy, through DOE-HQ Transportation Management Division, requested Westinghouse Hanford Company (Westinghouse Hanford) to review UF6 packaging tiedown and shipping practices used by PORTS, and where possible and appropriate, provide recommendations for enhancing these practices. Consequently, a tram of two individuals from Westinghouse Hanford visited PORTS on March 5 and 6, 1990, for the purpose of conducting this review. The paper provides a brief discussion of the review activities and a summary of the resulting findings and recommendations. A detailed reporting of the review is documented in Reference 4

  8. Technology, Safety and Costs of Decommissioning a Reference Uranium Hexafluoride Conversion Plant

    Energy Technology Data Exchange (ETDEWEB)

    Elder, H. K.

    1981-10-01

    Safety and cost information is developed for the conceptual decommissioning of a commercial uranium hexafluoride conversion (UF{sub 6}) plant. Two basic decommissioning alternatives are studied to obtain comparisons between cost and safety impacts: DECON, and passive SAFSTOR. A third alternative, DECON of the plant and equipment with stabilization and long-term care of lagoon wastes. is also examined. DECON includes the immediate removal (following plant shutdown) of all radioactivity in excess of unrestricted release levels, with subsequent release of the site for public use. Passive SAFSTOR requires decontamination, preparation, maintenance, and surveillance for a period of time after shutdown, followed by deferred decontamination and unrestricted release. DECON with stabilization and long-term care of lagoon wastes (process wastes generated at the reference plant and stored onsite during plant operation} is also considered as a decommissioning method, although its acceptability has not yet been determined by the NRC. The decommissioning methods assumed for use in each decommissioning alternative are based on state-of-the-art technology. The elapsed time following plant shutdown required to perform the decommissioning work in each alternative is estimated to be: for DECON, 8 months; for passive SAFSTOR, 3 months to prepare the plant for safe storage and 8 months to accomplish deferred decontamination. Planning and preparation for decommissioning prior to plant shutdown is estimated to require about 6 months for either DECON or passive SAFSTOR. Planning and preparation prior to starting deferred decontamination is estimated to require an additional 6 months. OECON with lagoon waste stabilization is estimated to take 6 months for planning and about 8 months to perform the decommissioning work. Decommissioning cost, in 1981 dollars, is estimated to be $5.91 million for OECON. For passive SAFSTOR, preparing the facility for safe storage is estimated to cost $0

  9. Closedown programme for the uranium ore and processing plant at Eleshnitsa, Bulgaria

    International Nuclear Information System (INIS)

    The tailings pond of the uranium ore and resin processing plant at Eleshnitsa, Bulgaria has been subject to a rehabilitation programme under a phare contract. The tailings cover 34 ha behind a 70 m high dam. The volume of waste is 12 million m3. Furhermore, there are considerable areas with contaminated soils within the industrial area. In order to be able to prepare detailed design and full tender documents for the actual contractual works a number of additional studies has been performed. The studies include geophysical, geodetical and geotechnical surveys, piezometer installations, a sub-regional sampling survey of surface and groundwater and a laboratory scale water treatment test. From these studies final design data and parameters have been obtained with respect to long term dam-stability, composition of cover and shape of contouring of the tailings pond area, structures for diversion of upstream surface waters and size and type of waste water treatment plant. Based on this information are contract Dossiers prepared The main part of this paper deals with the rehabilitation concept to be used for the contractual works. A description of present-day conditions, starting point for the rehabilitation concept, is also presented. Specific emphasis is put on the long-term stability of the dam and covering of the tailings by a soil membrane, on the design of the waste water treatment plant and on the monitoring programmes to be put into place. Besides above mentioned more technical and environmental aspects of the closedown programme a preliminary planning as well as cost-estimates for the different contractual works are presented. (orig.)

  10. Influence of uranium speciation on its accumulation and translocation in three plant species: Oilseed rape, sunflower and wheat

    International Nuclear Information System (INIS)

    Chemical speciation greatly influences the accumulation and distribution of metallic pollutants in plants. This study aimed at evaluating plant differential responses to various speciations of a same element. Uranium (U) was chosen as a model, to which wheat, oilseed rape and sunflower were exposed. Using ICP-MS elemental analysis, together with a panel of imaging techniques including scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM) and particle-induced X-ray emission spectroscopy (PIXE), we show that plant behavior in response to U follows three schemes. When exposed to UO22+ free ion, root adsorption and/or accumulation is high, but U transfer to the shoots is limited by precipitation on cell walls. Complexation with carbonate or citrate reduces U content in roots but drastically increases translocation to the shoots, concentrating U in leaves. Inversely, complexation with phosphate considerably reduces U accumulation in all plant tissues, by precipitation and adsorption of U-rich clusters on root epidermal cells. Finally, our results of U chemical extraction from plant tissues suggest the existence of U-binding proteins. Taken together, these data highlight the role of uranium speciation in the transfer of this metallic pollutant into plants and lead to a better understanding of the mechanisms governing its mobilization, accumulation and distribution in plants. These results will be helpful to improve phyto remediation technology of contaminated soils. (authors)

  11. Rapid laser fluorometric method for the determination of uranium in soil, ultrabasic rock, plant ash, coal fly ash and red mud samples

    International Nuclear Information System (INIS)

    A simple and rapid laser fluorometric determination of trace and ultra trace level of uranium in a wide variety of low uranium content materials like soil, basic and ultra basic rocks, plant ash, coal fly ash and red mud samples is described. Interference studies of some common major, minor and trace elements likely to be present in different geological materials on uranium fluorescence are studied using different fluorescence enhancing reagents like sodium pyrophosphate, orthophosphoric acid, penta sodium tri-polyphosphate and sodium hexametaphosphate. The accurate determination of very low uranium content samples which are rich in iron, manganese and calcium, is possible only after the selective separation of uranium. Conditions suitable for the quantitative single step extraction of 25 ng to 20 μg uranium with tri-n-octylphosphine oxide and single step quantitative stripping with dilute neutral sodium pyrophosphate, which also acts as fluorescence enhancing reagent is studied. The aqueous strip is used for the direct laser fluorometric measurement without any further pretreatment. The procedure is applied for the determination of uranium in soil, basalt, plant ash, coal fly ash and red mud samples. The accuracy of the proposed method is checked by analyzing certain standard reference materials as well as synthetic sample with known quantity of uranium. The accuracy and reproducibility of the method are fairly good with RSD ranging from 3 to 5% depend upon the concentration of uranium. (author)

  12. Uranium production

    International Nuclear Information System (INIS)

    The alltime high for uranium concentrate production is expected to be reached in 1980. The average grade of ore fed to process will be up about 10% from last year. Some curtailments in uranium processing were announced, but three new processing plants began production in 1980. The prospects for 1981 are not as encouraging. The continuation of low prices and slow demand for U3O8 are expected to be reflected in a significant reduction in overall production and in the postponement of some plans for expansion and construction of uranium processing facilities. Increases in production capacity will occur when Plateau Resource's 750 TPD mill at Ticaboo, Utah, starts up early next year, and additional production of byproduct uranium is expected from western phosphate operations and from the southern states. These increases in capacity, however, will not offset the cutbacks in uranium processing already in force together with the additional curtailments anticipated during the course of 1981

  13. Recovery of valuable products from the raffinate of uranium and thorium pilot-plant

    International Nuclear Information System (INIS)

    IPEN-CNEN/SP has being very active in refining yellow cake to pure ammonium diuranate which is converted to uranium trioxide, uranium dioxide, uranium tetra-and hexa-fluoride in sequential way. The technology of the thorium purification and its conversion to nuclear grade products has been a practice since several years as well. For both elements the major waste to be worked is the raffinate from purification via TBP-varsol in pulsed columns. In this paper the actual processing technology is reviewed with special emphasis on the recovery of valuable products, mainly nitric acid, ammonium nitrate, uranium, thorium and rare earth elements. Ammonium nitrate from the precipitation of uranium diuranate is of good quality, being radioactivity and uranium-free, and recommended to be applied as fertilizer. In conclusion the main effort is to maximize the recycle and reuse of the above mentioned chemicals. (author)

  14. Results from uranium deposition studies for development of a limited frequency-unannounced access inspection strategy for gas centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Uranium deposition studies were performed on a test loop system designed to simulate process gas flow through the header piping of a gas centrifuge enrichment plant. The objectives of these studies were to investigate the effectiveness of an in-line gaseous cleaning agent in removing uranium in pipe deposits and to analyze long-term deposition growth and isotopic exchange under simulated centrifuge plant operating conditions. The test loop studies are described, the results are reported, and the implications for analyzing actual plant data are discussed. Results indicate that (1) 93% of the uranium deposit is removed within 15 min when a pipe is pressurized with gaseous ClF3, (2) the isotopic abundance of a highly enriched uranium deposit remains unchanged when UF6 of a lower assay is introduced into the pipe, and (3) air inleakage will be the cause of the largest deposits in centrifuge plant process header pipes

  15. Uranium from phosphate ores

    International Nuclear Information System (INIS)

    The following topics are described briefly: the way phosphate fertilizers are made; how uranium is recovered in the phosphate industry; and how to detect covert uranium recovery operations in a phsophate plant

  16. Non-destructive assay system for uranium and plutonium in input dissolver solution of Tokai Reprocessing Plant

    International Nuclear Information System (INIS)

    A nondestructive assay system for the accountability of uranium and plutonium in input dissolver solution of a nuclear reprocessing plant, named 'Richman's Densitometer', has been developed at the Tokai Reprocessing Plant (TRP). The development of this system has been carried out as a part of Japan Support Program for Agency Safeguards (JASPAS). The system is divided into two nondestructive assay parts, K-edge densitometer (KED) and X-ray fluorescence (XRF) spectrometer. The K-edge densitometry is used to determine the uranium concentration, whereas XRF analysis is used to determine U/Pu weight ratio. The plutonium concentration can be calculated from both the measurement results. The principal of richman's densitometry and the experimental results are discussed in this paper. (author)

  17. Long-term outlook for global natural uranium and uranium enrichment supply and demand situations after the impact of Fukushima Daiichi Nuclear Power Plant accident

    International Nuclear Information System (INIS)

    In this paper, the authors propose long-term projections of global nuclear power generation, uranium production, and uranium enrichment capacities by region, and estimate the trade flows of natural uranium and uranium enrichment activities in 2020 and 2035. In spite of the rapid nuclear power generation capacity growth expected especially in Asia, the natural uranium and uranium enrichment trade will not be tightened by 2020 due to the projected increase in both natural uranium production and uranium enrichment capacities, which may cause a drop in natural uranium and uranium enrichment prices. Thus, there is a great possibility that the current projects for capacity expansion will be delayed considerably. However, in the 'high-demand scenario', where nuclear expansion will be accelerated due to growing concerns about global warming and energy security issues, additional investments in uranium production and enrichment facilities will be needed by 2035. In Asia, the self-sufficiency ratio for both natural uranium supply and uranium enrichment activities will remain relatively low until 2035. However, the Herfindahl-Hirschman (HH) index of natural uranium and uranium enrichment activity trade to Asia will be lowered considerably up to 2035, indicating that nuclear capacity expansion can contribute to enhancing energy security in Asia. (author)

  18. Licensing of the Process Uranium Plant Mineral, Retortillo-Santidad; Licenciamiento de la Planta de Proceso de Mineral de Uranio Retortillo-Sanidad

    Energy Technology Data Exchange (ETDEWEB)

    Blazquez Arroyo, E.; Colilla Peletero, J.; Bellon del Rosal, F.; Mancipe Jimenez, D. C.; Garrido Delgado, C.; Garcia-Bermejo Fernandez, R.

    2013-07-01

    Berkeley Minera Spain, S.A. provides for the operation of the concession Retortillo-Santidad (Salamanca) mining and construction of a beneficiation plant of uranium ore, for the production of uranium concentrate (Yellow cake). In Spain, the project Quercus, ENUSA, obtained the last prior authorization in 1979. Since then, there has been a continuous evolution in the aspects technical and regulatory. This paper is the documentation and content necessary for the licensing of a uranium production plant. In particular, to obtain the prior authorization as radioactive installation of 1st category (RINR).

  19. LABORATORY DEMONSTRATION OF A MULTISENSOR UNATTENDED CYLINDER VERIFICATION STATION FOR URANIUM ENRICHMENT PLANT SAFEGUARDS

    Energy Technology Data Exchange (ETDEWEB)

    Goodman, David I [Univ. of Michigan, Ann Arbor, MI (United States); Rowland, Kelly L [Univ. of California, Berkeley, CA (United States); Smith, Sheriden [Colorado State Univ., Fort Collins, CO (United States); Miller, Karen A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Flynn, Eric B. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-01-10

    The objective of safeguards is the timely detection of the diversion of a significant quantity of nuclear materials, and safeguarding uranium enrichment plants is especially important in preventing the spread of nuclear weapons. The IAEA’s proposed Unattended Cylinder Verification Station (UCVS) for UF6 cylinder verification would combine the operator’s accountancy scale with a nondestructive assay system such as the Passive Neutron Enrichment Meter (PNEM) and cylinder identification and surveillance systems. In this project, we built a laboratory-scale UCVS and demonstrated its capabilities using mock UF6 cylinders. We developed a signal processing algorithm to automate the data collection and processing from four continuous, unattended sensors. The laboratory demonstration of the system showed that the software could successfully identify cylinders, snip sensor data at the appropriate points in time, determine the relevant characteristics of the cylinder contents, check for consistency among sensors, and output the cylinder data to a file. This paper describes the equipment, algorithm and software development, laboratory demonstration, and recommendations for a full-scale UCVS.

  20. Verification of nuclear material balances: General theory and application to a highly enriched uranium fabrication plant

    International Nuclear Information System (INIS)

    In the theoretical part it is shown that under the assumption, that in case of diversion the operator falsifies all data by a class specific amount, it is optimal in the sense of the probability of detection to use the difference MUF-D as the test statistics. However, as there are arguments for keeping the two tests separately, and furthermore, as it is not clear that the combined test statistics is optimal for any diversion strategy, the overall guaranteed probability of detection for the bivariate test is determined. A numerical example is given applying the theoretical part. Using the material balance data of a Highly Enriched Uranium fabrication plant the variances of MUF, D (no diversion) and MUF-D are calculated with the help of the standard deviations of operator and inspector measurements. The two inventories of the material balance are stratified. The samples sizes of the strata and the total inspection effort for data verification are determined by game theoretical methods (attribute sampling). On the basis of these results the overall detection probability of the combined system (data verification and material accountancy) is determined both for the MUF-D test and the bivariate (D,MUF) test as a function of the goal quantity. The results of both tests are evaluated for different diversion strategies. (orig./HP)

  1. Investigation into potential international safeguards for the Gronau uranium enrichment plant

    International Nuclear Information System (INIS)

    Measurements carried out in the SP4 GUZ enrichment plant at Almelo/Netherlands were intended to verify the applicability of the gamma spectroscopy on UF6 transporting pipes for nondestructive assessment of uranium enrichment, a method already adopted by the IAEA. The measuring point had to be installed at the pipes between the top section and the first valve, i.e. within the cascades. Taking into consideration the results of the Hexapartite Safeguards Project, the measurements were to be used to define a 'go/no go' decision with regard to a running or just finished production process. The report explains the measuring method applied and the subsequent evaluations, discusses the results and presents conclusions to be drawn. The applicability of the method to safeguards purposes is denied. The activities reported further include studies of the electronic seal system VACOSS 3, and of alternatives such as the available metal cap seal and an adhesive seal currently under review for improvement. The technical aspects of sealing methods and sealing tool efficiencies with a view to safeguarding intentions are discussed. The metal cap seal is shown to be better than the VACOSS seal in technical terms for purposes such as sealing of containers for enriched material, whereas the sealing of cases for safe enclosure of documents or devices is best achieved by the VACOSS seal. (orig./HP)

  2. Safeguards Guidance for Designers of Commercial Nuclear Facilities - International Safeguards Requirements for Uranium Enrichment Plants

    International Nuclear Information System (INIS)

    For the past two years, the United States National Nuclear Security Administration, Office of International Regimes and Agreements (NA-243), has sponsored the Safeguards-by-Design Project, through which it is hoped new nuclear facilities will be designed and constructed worldwide more amenable to nuclear safeguards. In the course of this project it was recognized that commercial designer/builders of nuclear facilities are not always aware of, or understand, the relevant domestic and international safeguards requirements, especially the latter as implemented by the International Atomic Energy Agency (IAEA). To help commercial designer/builders better understand these requirements, a report was prepared by the Safeguards-by-Design Project Team that articulated and interpreted the international nuclear safeguards requirements for the initial case of uranium enrichment plants. The following paper summarizes the subject report, the specific requirements, where they originate, and the implications for design and construction. It also briefly summarizes the established best design and operating practices that designer/builder/operators have implemented for currently meeting these requirements. In preparing the subject report, it is recognized that the best practices are continually evolving as the designer/builder/operators and IAEA consider even more effective and efficient means for meeting the safeguards requirements and objectives.

  3. Safeguards Guidance for Designers of Commercial Nuclear Facilities – International Safeguards Requirements for Uranium Enrichment Plants

    Energy Technology Data Exchange (ETDEWEB)

    Philip Casey Durst; Scott DeMuth; Brent McGinnis; Michael Whitaker; James Morgan

    2010-04-01

    For the past two years, the United States National Nuclear Security Administration, Office of International Regimes and Agreements (NA-243), has sponsored the Safeguards-by-Design Project, through which it is hoped new nuclear facilities will be designed and constructed worldwide more amenable to nuclear safeguards. In the course of this project it was recognized that commercial designer/builders of nuclear facilities are not always aware of, or understand, the relevant domestic and international safeguards requirements, especially the latter as implemented by the International Atomic Energy Agency (IAEA). To help commercial designer/builders better understand these requirements, a report was prepared by the Safeguards-by-Design Project Team that articulated and interpreted the international nuclear safeguards requirements for the initial case of uranium enrichment plants. The following paper summarizes the subject report, the specific requirements, where they originate, and the implications for design and construction. It also briefly summarizes the established best design and operating practices that designer/builder/operators have implemented for currently meeting these requirements. In preparing the subject report, it is recognized that the best practices are continually evolving as the designer/builder/operators and IAEA consider even more effective and efficient means for meeting the safeguards requirements and objectives.

  4. Plant uptake of depleted uranium from manure-amended and citrate treated soil.

    Science.gov (United States)

    Sevostianova, Elena; Lindemann, William C; Ulery, April L; Remmenga, Marta D

    2010-08-01

    Six plant species were tested for their ability to accumulate depleted uranium in their above-ground biomass from deployed munitions contaminated soil in New Mexico. In greenhouse experiments, Kochia (Kochia scoparia L. Schrad.) and pigweed (Amaranthus retroflexus L) were grown with steer manure added at rates of 22.4, 44.8, and 89.6 Mg ha(-1). Citric acid and glyphosate (N-(phosphonomethyl) glycine) applied at the end of the growing season increased DU concentrations from 2.5 to 17 times. Leaf and stem DU concentrations in kochia increased from 17.0 to 41.9 mg kg(-1) and from 3.5 to 18.0 mg kg(-1), respectively. In pigweed, leaf and stem DU concentrations increased from 1.0 to 17.3 and from 1.0 to 4.7 mg kg(-1), respectively. Manure generally decreased or had no effect on DU uptake. The effect of citric acid and ammonium citrate on DU uptake by kochia, sunflower (Helianthus annuus L), and sweet corn (Zea mays L) was also studied. Ammonium citrate was just as effective in enhancing DU uptake as citric acid. This implies that the citrate ion is more important in DU uptake and translocation than the solubilization of DU through acidification. In both experiments, leaves had higher DU concentrations than stems. PMID:21166280

  5. RADIO FREQUENCY IDENTIFICATION DEVICES: EFFECTIVENESS IN IMPROVING SAFEGUARDS AT GAS-CENTRIFUGE URANIUM-ENRICHMENT PLANTS.

    Energy Technology Data Exchange (ETDEWEB)

    JOE,J.

    2007-07-08

    Recent advances in radio frequency identification devices (RFIDs) have engendered a growing interest among international safeguards experts. Potentially, RFIDs could reduce inspection work, viz. the number of inspections, number of samples, and duration of the visits, and thus improve the efficiency and effectiveness of international safeguards. This study systematically examined the applications of RFIDs for IAEA safeguards at large gas-centrifuge enrichment plants (GCEPs). These analyses are expected to help identify the requirements and desirable properties for RFIDs, to provide insights into which vulnerabilities matter most, and help formulate the required assurance tests. This work, specifically assesses the application of RFIDs for the ''Option 4'' safeguards approach, proposed by Bruce Moran, U. S. Nuclear Regulatory Commission (NRC), for large gas-centrifuge uranium-enrichment plants. The features of ''Option 4'' safeguards include placing RFIDs on all feed, product and tails (F/P/T) cylinders, along with WID readers in all FP/T stations and accountability scales. Other features of Moran's ''Option 4'' are Mailbox declarations, monitoring of load-cell-based weighing systems at the F/P/T stations and accountability scales, and continuous enrichment monitors. Relevant diversion paths were explored to evaluate how RFIDs improve the efficiency and effectiveness of safeguards. Additionally, the analysis addresses the use of RFIDs in conjunction with video monitoring and neutron detectors in a perimeter-monitoring approach to show that RFIDs can help to detect unidentified cylinders.

  6. A holdup measurement system for enriched uranium at the Oak Ridge Y-12 plant

    International Nuclear Information System (INIS)

    There are increasing requirements in today's nuclear industry to conduct extensive radiation surveys on a repeated basis. There is also a growing need to analyze, trend, and document the results of these surveys in such a way that ensures any anomalies will be identified and corrected. A fundamental key to the success of these surveys is the type of portable instrumentation that is used to make the measurements. There are many excellent types of radiation meters available, but few have the ability to store the results internally. Without data storage capabilities, it is necessary to use lengthy, hand written log sheets for each survey and then requires manual input of the data later into a database to be analyzed. At the Oak Ridge Y-12 Plant, a system has been developed to overcome these shortcomings and meet the current radiation monitoring demands. The basic hardware of the system is a portable bar code reader and a portable radiation monitor that work together as a unit. The hardware, along with a specially designed database management package, allows for the automated collection of monitoring point identification numbers and the corresponding radiation levels. Besides radiation surveys, there are other possible uses of this bar code reader and a radiation meter combination. The basic radiation meter can be used with a number of different types of detector probes. With this equipment combination, Heath Physics monitoring surveys could be automated. In the realm of Nuclear Materials Control and Accountability, the equipment combination has the potential of automating semi-quantitative analysis of uranium holdup in all process equipment. The Safeguard and Security organization could use this new combination of equipment to record radiation monitoring data at the Plant's material transfer stations. The basic bar code reader is almost a micro-mini computer

  7. Compucea: A high performance analysis procedure for timely On-site Uranium Accountancy Verification in Leu Fuel Fabrication Plants

    International Nuclear Information System (INIS)

    COMPUCEA (Combined Procedure for Uranium Concentration and Enrichment Assay) is used for on-site analytical measurements in support of joint EURATOM-IAEA inspections during physical inventory verification (PIV) campaigns in European Low-Enriched Uranium (Leu) fuel fabrication plants. The analytical technique involves the accurate determination of the uranium element content by energy-dispersive X-ray absorption edge spectrometry (L-edge densitometry) and of the 235 U enrichment by gamma spectrometry with a LaBr3(Ce) detector. For evaluation of the LaBr3 spectra a modified version of the NaIGEM code is used, which has recently been adapted to handle the presence of reprocessed uranium. This paper describes the technique, setup and calibration procedure of the instrument. Results from PIV campaigns in 2007 and 2008 are presented, which demonstrate the performance of the technique. First results obtained with a sandwich detector configuration for enhanced detection efficiency of the passive gamma spectrometry are discussed.

  8. Derivation of residual radioactive material guidelines for uranium in soil at the Middlesex Sampling Plant Site, Middlesex, New Jersey

    International Nuclear Information System (INIS)

    Residual radioactive material guidelines for uranium in soil were derived for the Middlesex Sampling Plant (MSP) site in Middlesex, New Jersey. This site has been designated for remedial action under the Formerly Utilized Sites Remedial Action Program (FUSRAP) of the US Department of Energy. The site became contaminated from operations conducted in support of the Manhattan Engineer District (MED) and the Atomic Energy Commission (AEC) between 1943 and 1967. Activities conducted at the site included sampling, storage, and shipment of uranium, thorium, and beryllium ores and residues. Uranium guidelines for single radioisotopes and total uranium were derived on the basis of the requirement that the 50-year committed effective dose equivalent to a hypothetical individual living or working in the immediate vicinity of the MSP site should not exceed a dose of 30 mrem/yr following remedial action for the current-use and likely future-use scenarios or a dose of 100 mrem/yr for less likely future-use scenarios. The RESRAD computer code, which implements the methodology described in the DOE manual for establishing residual radioactive material guidelines, was used in this evaluation. Four scenarios were considered for the site. These scenarios vary regarding future land use at the site, sources of water used, and sources of food consumed

  9. The relationship of JNC and JCO in the uranium processing plant criticality accident. The second revision edition

    International Nuclear Information System (INIS)

    On September 30th 1999, the criticality accident occurred at JCO's uranium conversion building in Tokai. The accident occurred during reconversion from U3O8 to uranium nitrate solution (UNH) with uranium enriched 18.8% and about 60 kgU. JCO contracted with JNC to supply UNH that is fuel material for the experimental fast breeder reactor 'JOYO'. JNC has contracted with JCO that had started nuclear fuel material processing business following a definite policy of Japanese government and developed SUMITOMO ADU PROCESS'. JNC made the first contract with JCO in 1985 and has made a contact every year. There had never been a problem in their products. JNC inspected products based on contract. JNC discharge our duty as customer inspecting products based on contract. As for safety control, JCO had taken licensing safety review and had been permitted to be 'a processing facility'. Therefore JNC understood that JCO produced following this license. 'The Uranium Processing Plant Criticality Accident Investigation' showed that JCO had been taking a different method from the permit and violating the license. However JNC had never been explained about that and JCO's operation procedures had never described about that. Therefore the Criticality Accident couldn't be avoided. The reports is the revision of former JNC TN8420 2003-003. (author)

  10. Decommissioning of a uranium conversion plant and a low level radioactive waste for a long term disposal - 16071

    International Nuclear Information System (INIS)

    A decommissioning project for a uranium conversion plant was conducted to restore it to a safe environmental condition and minimal low level radioactive wastes which were converted to stable chemical forms for a long term disposal. In the middle of 2004, a decommissioning program for a conversion plant, which was constructed in 1982, and treated about 300 tons of natural uranium until it was shut down in 1992, obtained its approval from the regulatory body. Actual dismantling and decontaminating activities have been performed since July 2004 and will be finished by December 2009. The decommissioning works were mainly divided into two parts: the inside of the building containing the process equipment; the lagoon sludge generated during the plant operation. The decommissioning of the inside of the building was carried out by dismantling the process equipment, which were firstly segmented and decontaminated by polishing and washing with steam and chemicals or melting, and then decontamination for the surfaces inside the building by excavating or grinding the concrete walls. The decontamination goals were below 0.2 Bq/g for the metallic segments and below 0.4 Bq/cm2 for the concrete walls. Decontamination methods were selected according to the degree of contamination and a minimization of the low level radioactive wastes was conducted throughout the decommissioning work. The lagoon sludge waste had two types, one was an various inorganic nitrate salt mixture containing a very low concentration of uranium, about 200∼300 ppm, in Lagoon-II and the other was an inorganic nitrate salt mixture containing a few percent of uranium in Lagoon-I. To treat these sludge wastes a thermal decomposition facility was constructed and operated to produce stable sludge wastes containing uranium oxides which are stable in the air. The final sludge wastes after a thermal treating for the sludge waste of Lagoon-I could be reused. The final residual radioactivity for the inside of the

  11. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Paducah Gaseous Diffusion Plant site

    Energy Technology Data Exchange (ETDEWEB)

    Marmer, G.J.; Dunn, C.P.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Yuen, C.R.; Cleland, J.H. (ed.)

    1991-09-01

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. The U-235 atoms are ionized when precisely tuned laser light -- of appropriate power, spectral, and temporal characteristics -- illuminates the uranium vapor and selectively photoionizes the U-235 isotope. A programmatic document for use in screening DOE site to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the PGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. 65 refs., 15 tabs.

  12. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Paducah Gaseous Diffusion Plant site

    International Nuclear Information System (INIS)

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. The U-235 atoms are ionized when precisely tuned laser light -- of appropriate power, spectral, and temporal characteristics -- illuminates the uranium vapor and selectively photoionizes the U-235 isotope. A programmatic document for use in screening DOE site to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the PGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. 65 refs., 15 tabs

  13. Speciation of uranium in plants upon root accumulation and root-to-shoot translocation: A XAS and TEM study

    International Nuclear Information System (INIS)

    Uranium mobilization in surface waters and soils is highly dependent on its speciation. Links between U speciation and in plants mobility remain unclear, although understanding this relationship is essential in a view to properly develop efficient phyto remediation strategies. To address this question, we used X-ray absorption spectroscopy (XAS) and transmission electron microscopy (TEM) to determine U speciation and distribution in plant roots and leaves when exposed to U in the form of different chemical species. Our results indicate that U complexation with endogenous phosphate residues leads to its precipitation and fixation in plant organs, avoiding translocation from roots to leaves. We also show that complexation with a strong ligand such as citrate in exposure solution circumvents this precipitation, and enhances root-to-shoot translocation, in a U-carboxylate complex form. These results highlight correlations between U speciation in the environment and its mobility pattern in plants, which would help for phyto remediation purposes. (authors)

  14. The elimination of chlorinated, chlorofluorocarbon, and other RCRA hazardous solvents from the Y-12 Plant's enriched uranium operations

    International Nuclear Information System (INIS)

    A major driving force in waste minimization within the plant is the reduction of mixed radioactive wastes associated with operations on highly enriched uranium. High enriched uranium has a high concentration of the uranium-235 isotope (up to 97.5% enrichment) and is radioactive, giving off alpha and low level gamma radiation. The material is fissionable with as little as two pounds dissolved in water being capable of producing a spontaneous chain reaction. For these reasons the material is processed in small batches or small geometries. Additionally, the material is completely recycled because of its strategic and monetary value. Since the early eighties, the plant has had an active waste minimization program which has concentrated on substitution of less hazardous solvents wherever possible. The following paper summarizes efforts in two areas - development of a water-based machining coolant to replace perchloroethylene and substitution of an aliphatic solvent to replace solvents producing hazardous wastes as defined by the Resource, Conservation, and Recovery Act (RCRA)

  15. Vegetation composition and 226Ra uptake by native plant species at a uranium mill tailings impoundment in South China

    International Nuclear Information System (INIS)

    A field investigation was conducted for the vegetation composition and 226Ra uptake by native plant species at a uranium mill tailings impoundment in South China. 80 species belonging to 67 genera in 32 families were recorded in the sampling sites. The Poaceae and Asteraceae were the dominant families colonizing the impoundment. The number of the plant species and vegetation community composition in the sampling sites seemed most closely related to the activities of 226Ra and the pH value of the uranium tailings. The plant species in the sampling sites with relatively low activities of 226Ra and relatively high pH value formed a relatively stable vegetation community. The plant species in the sampling sites with medium activities of 226Ra and medium pH value formed the transitional vegetation community. The plant species in the sampling sites with relatively high activities of 226Ra and relatively low pH value formed a simple unstable vegetation community that was similar to that on the unused grassland. The activities of 226Ra and transfer factors (TFs) varied greatly with the plant species. The high activities of 226Ra and TFs were found in the leaves of Pteris multifida (150.6 Bq/g of AW; 9.131), Pteridium aquilinum (122.2 Bq/g of AW; 7.409), and Dryopteris scottii (105.7 Bq/g of AW; 6.408). They satisfied the criteria for a hyperaccumulator for 226Ra. They may be the candidates for phytoremediation of 226Ra in the uranium mill tailings impoundment areas and the contaminated soils around. - Highlights: • Vegetation composition of native plant species at an impoundment was analyzed. • 226Ra uptake by native plant species at the impoundment was investigated. • Poaceae and Asteraceae were the dominated families colonizing this impoundment. • The plant species and composition were related to activities of 226Ra and pH. • Three plant species were found to be hyperaccumulators for 226Ra

  16. How to go on with Czech uranium: does current uranium mining in the Czech Republic cover Czech nuclear power plants' needs?

    International Nuclear Information System (INIS)

    The overview covers the history of uranium mining in the Czech Republic (description of the deposits and overview of their exploitation) and current needs for uranium and the status of uranium resources in the Czech Republic (uranium mining at the Rozna deposit, overview of exploitation of the deposit, uranium ore reserves, possibilities of future use of the Rozna deposit, the Brzkov and Horni Veznice deposits, and the use of mine waters as a secondary uranium source). It is concluded that in view of the current development of uses of raw materials for the power sector worldwide and increasing dependence of many countries (including the Czech Republic) on imports of such raw materials (often from politically unstable countries) it is strategically important to maintain domestic uranium mining to cover the needs of the Czech power sector. Uranium reserves and preconditions for their mining still exist in this country. (P.A.)

  17. Implementation trial of high performance trace analysis/environmental sampling (HPTA/ES) in uranium centrifuge enrichment plants

    International Nuclear Information System (INIS)

    Field trials have demonstrated that the analysis of particles upon swipes obtained from inside nuclear installations provides clear signatures of past operations in that installation. This can offer a valuable tool for gaining assurance regarding the compliance with declared activities and the absence of undeclared activities (e.g. enrichment, reprocessing, and reactor operation) at such sites. This method, known as 'Environmental Sampling' (ES) or 'High Performance Trace Analysis' (HPTA) in EURATOM terminology, is at present being evaluated by the EURATOM Safeguards Directorate (ESD) in order to assess its possible use in nuclear installations within the European Union. It is expected that incorporation of HPTA/ES of sample collection and analysis into routine inspection activities will allow EURATOM to improve the effectiveness of safeguards in these installations and hopefully save inspection resources as well. The EURATOM Safeguards Directorate has therefore performed implementation trials involving the collection of particles by the so-called swipe sampling method in uranium centrifuge enrichment plants and hot cells in the European Union. These samples were subsequently analysed by the Joint Research Centre, Institute for Transuranium Elements (ITU) in Karlsruhe. Sampling points were chosen on the basis of the activities performed in the vicinity and by considering the possible ways through which particles are released, diffused and transported. The aim was to test the efficiency of the method as regards: the collection of enough representative material; the identification of a large enough number of uranium particles; the accurate measurement of the enrichment of the uranium particles found on the swipe; the representativity of the results in respect of past activities in the plant; the capability of detecting whether highly enriched uranium has been produced, used or occasionally transported in a location where low enriched uranium is routinely produced in

  18. Bioaccumulation of polonium ({sup 210}Po) and uranium ({sup 234}U, {sup 238}U) in plants around phosphogypsum waste heap in Wislinka (northern Poland)

    Energy Technology Data Exchange (ETDEWEB)

    Borylo, A.; Skwarzec, B. [Gdansk Univ. (Poland). Faculty of Chemistry

    2011-07-01

    In the study the activities of polonium {sup 210}Po and uranium {sup 234}U, {sup 238}U in plants, collected near phosphogypsum waste heap in Wis'linka (northern Poland), were determined by using the alpha spectrometry. The obtained results revealed that the concentrations of {sup 210}Po, {sup 234}U, and {sup 238}U in the analyzed plants were differentiated. In the analyzed flora organisms the highest amounts of polonium and uranium were found in ruderal plant samples as well as willow samples (Salix viminalis) from protection zone of phosphogypsum waste heap. The concentrations of {sup 210}Po, {sup 234}U and {sup 238}U in the analyzed plants were higher in roots than in green parts of plants. The higher concentrations of {sup 210}Po and {sup 238}U radionuclides were estimated for hydrophyte (common sedge Carex nigra Reichard), the favourite habitat of which is particularly wet meadow and for plants collected in the vicinity of phosphogypsum waste heap. The major source of polonium and uranium in analyzed plants is root system. The values of {sup 234}U/ {sup 238}U activity ratio in all analyzed plants are closed to one, what indicated that source of uranium in analyzed plants is phosphogypsum. The highest uranium and polonium concentrations were characterized for plants, which are covered with tomentose. The comparability polonium and uranium contents were confirmed in edible plants, but higher accumulation was determined in ripe species than immature species of vegetables. The higher polonium and uranium concentrations were noticed in green parts of plant, the lower in roots. Polonium concentration in cultivated plants samples was not species diverse. Therefore, the significant source of polonium and uranium in analyzed plants is wet and dry atmospheric falls gathering the soil and air dust from phosphogypsum waste dump. The maximum {sup 210}Po and {sup 238}U radionuclides concentrations were found in green parts of red beet (Beta vulgaris esculenta), the

  19. Long-term biobarriers to plant and animal intrusions of uranium tailings

    International Nuclear Information System (INIS)

    The objective of this project was to develop and evaluate the effectiveness of physical and chemical barriers designed to prevent plant and animal breachment of uranium mill tailings containment systems for an extended period of time. A polymeric carrier/biocide delivery system was developed and tested in the laboratory, greenhouse and field. A continuous flow technique was established to determine the release rates of the biocides from the PCD systems; polymeric carrier specifications were established. Studies were conducted to determine effective biocide concentrations required to produce a phytotoxic response and the relative rates of phytotoxin degradation resulting from chemical and biological breakdown in soils. The final PCD system developed was a pelletized system containing 24% trifluralin, 18% carbon black and 58% polymer. Pellets were placed in the soil at the Grand Junction U-tailings site at one in. and two in. intervals. Data obtained in the field determined that the pellets released enough herbicide to the soil layer to stop root elongation past the barrier. Physical barriers to subsurface movement of burrowing animals were investigated. Small crushed stone (1 to 1 1/2 in. diameter) placed over asphalt emulsion and multilayer soil seals proved effective as barriers to a small mammal (ground squirrels) but were not of sufficient size to stop a larger animal (the prairie dog). No penetrations were made through the asphalt emulsion or the clay layer of the multilayer soil seals by either of the two mammals tested. A literature survey was prepared and published on the burrowing habits of the animals that may be found at U-tailings sites

  20. Recovery of valuable products in the raffinate of the uranium and thorium pilot-plant

    International Nuclear Information System (INIS)

    IPEN-CNEN/SP has being very active in refining yellowcake to pure ammonium diuranate which is converted to uranium trioxide, uranium dioxide, tetra - and hexafluoride in a sequential way. The technology of the thorium purification and its conversion to nuclear grade products has been a practice since several years as well. For both elements the major to be worked is the raffinate from the solvent extraction colum where and thorium are purified via TBP-varsol in pulsed columns. In this paper the actual processing technology is reviewed with special emphasis on the recovery of valuable products, mainly nitric acid and ammonium nitrate. Distilled nitric acid and the final sulfuric acid as residue are recycle. Ammonium nitrate from the precipitation of uranium diuranate is of good quality, being radioactivity and uranium - free, and recommended to be applied as fertilizer. In conclusion the main effort is to maximize the recycle and reuse of the above mentioned chemicals. (author)

  1. Study of the effect of uranium and thorium on the growing of pepper (Capsicum annuum var. longum) and cucumber (Cucumis sativus) plants

    International Nuclear Information System (INIS)

    The transportation rate of uranium and thorium to different plants grown in soils having high level of these elements varies closely with the plant characteristics. In this study, the pepper (Capsicum annuum var. longum) and cucumber (Cucumis sativus) plants were chosen as vegetables which are commonly consumed over different regions by different populations. The results obtained can be summarized as follows: (1) High uranium concentration in the soil prevents the growing of the plants. Only the plants in the pot having the uranium concentration of about 263 ppm grew significantly. The plants in other pots having a higher concentration turned pale and died in a few weeks. (2) In the pot having thorium level of about 263 ppm, the plants were well grown and fruited in comparison to the control plants, but the increase of thorium concentration inversely influenced their growing. (3) The gross activities measured in different parts of the plants were not particularly high, however, in both cases the maximum activities were measured in the stems rather than in the fruits and leaves. (4) The plants grown in soils having thorium content lived longer than the control plants and at the greenhouse conditions indicated above, all plants lived more than one whole year flowering and fruiting. (author)

  2. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Portsmouth Gaseous Diffusion Plant site

    International Nuclear Information System (INIS)

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. In the 1970s, the US Department of Energy (DOE) began investigating more efficient and cost-effective enrichment technologies. In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser isotope Separation (U-AVLIS) technology with the near-term goal to provide the necessary information to make a deployment decision by November 1992. Initial facility operation is anticipated for 1999. A programmatic document for use in screening DOE sites to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. The final evaluation, which included sensitivity studies, identified the Oak Ridge Gaseous Diffusion Plant (ORGDP) site, the Paducah Gaseous Diffusion Plant (PGDP) site, and the Portsmouth Gaseous Diffusion Plant (PORTS) site as having significant advantages over the other sites considered. This environmental site description (ESD) provides a detailed description of the PORTS site and vicinity suitable for use in an environmental impact statement (EIS). This report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during site visits. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use. Socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3

  3. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Portsmouth Gaseous Diffusion Plant site

    Energy Technology Data Exchange (ETDEWEB)

    Marmer, G.J.; Dunn, C.P.; Filley, T.H.; Moeller, K.L.; Pfingston, J.M.; Policastro, A.J.; Cleland, J.H.

    1991-09-01

    Uranium enrichment in the United States has utilized a diffusion process to preferentially enrich the U-235 isotope in the uranium product. In the 1970s, the US Department of Energy (DOE) began investigating more efficient and cost-effective enrichment technologies. In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser isotope Separation (U-AVLIS) technology with the near-term goal to provide the necessary information to make a deployment decision by November 1992. Initial facility operation is anticipated for 1999. A programmatic document for use in screening DOE sites to locate a U-AVLIS production plant was developed and implemented in two parts. The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. The final evaluation, which included sensitivity studies, identified the Oak Ridge Gaseous Diffusion Plant (ORGDP) site, the Paducah Gaseous Diffusion Plant (PGDP) site, and the Portsmouth Gaseous Diffusion Plant (PORTS) site as having significant advantages over the other sites considered. This environmental site description (ESD) provides a detailed description of the PORTS site and vicinity suitable for use in an environmental impact statement (EIS). This report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during site visits. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use. Socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3.

  4. Levels of radionuclides in plant samples collected around the uranium conversion facility following the criticality accident in Tokai-mura

    International Nuclear Information System (INIS)

    Concentrations of artificial radionuclides in plant samples collected in the surrounding areas of the uranium conversion facility of JCO Company Limited were studied following the criticality accident in Tokai-mura. Radionuclides detected in plants were 131I, 133I, 140Ba-140La and 137Cs. The highest concentrations of the nuclides were found in samples collected near the facility or its ventilation exhaust and the concentrations decreased sharply with distance. The origins of 140Ba-140La and 137Cs were thought to be from 140Xe and 137Xe, respectively, which were produced in the fission event and released to the atmosphere. The average 131I/133I activity ratio was about 21 (decay-corrected to the end of fission). Levels of the radionuclides in plants outside the JCO grounds were markedly below the intervention levels for foodstuffs in Japan

  5. Feasibility Study on the Use of On-line Multivariate Statistical Process Control for Safeguards Applications in Natural Uranium Conversion Plants

    Energy Technology Data Exchange (ETDEWEB)

    Ladd-Lively, Jennifer L [ORNL

    2014-01-01

    The objective of this work was to determine the feasibility of using on-line multivariate statistical process control (MSPC) for safeguards applications in natural uranium conversion plants. Multivariate statistical process control is commonly used throughout industry for the detection of faults. For safeguards applications in uranium conversion plants, faults could include the diversion of intermediate products such as uranium dioxide, uranium tetrafluoride, and uranium hexafluoride. This study was limited to a 100 metric ton of uranium (MTU) per year natural uranium conversion plant (NUCP) using the wet solvent extraction method for the purification of uranium ore concentrate. A key component in the multivariate statistical methodology is the Principal Component Analysis (PCA) approach for the analysis of data, development of the base case model, and evaluation of future operations. The PCA approach was implemented through the use of singular value decomposition of the data matrix where the data matrix represents normal operation of the plant. Component mole balances were used to model each of the process units in the NUCP. However, this approach could be applied to any data set. The monitoring framework developed in this research could be used to determine whether or not a diversion of material has occurred at an NUCP as part of an International Atomic Energy Agency (IAEA) safeguards system. This approach can be used to identify the key monitoring locations, as well as locations where monitoring is unimportant. Detection limits at the key monitoring locations can also be established using this technique. Several faulty scenarios were developed to test the monitoring framework after the base case or normal operating conditions of the PCA model were established. In all of the scenarios, the monitoring framework was able to detect the fault. Overall this study was successful at meeting the stated objective.

  6. Demand of natural uranium to satisfy the requirements of nuclear fuel of new nuclear power plants in Mexico

    International Nuclear Information System (INIS)

    Due to the expectation of that in Mexico new plants of nuclear energy could be installed, turns out from the interest to evaluate the uranium requirements to operate those plants and to also evaluate if the existing reserves in the country could be sufficient to satisfy that demand. Three different scenes from nuclear power plant expansion for the country are postulated here that are desirable for the diversification of generation technologies. The first scene considers a growth in the generation by nuclear means of two reactors of type ABWR that could enter operation by years 2015 and 2020, in the second considers the installation of four reactors but as of 2015 and new every 5 years, in the scene of high growth considers the installation of 6 reactors of the same type that in the other scenes, settling one every three years as of 2015. The results indicate that the uranium reserves could be sufficient to only maintain in operation to one of the reactors proposed by the time of their useful life. (Author)

  7. Bioaccumulation of 226Ra by plants growing in fresh water ecosystem around the uranium industry at Jaduguda, India

    International Nuclear Information System (INIS)

    A field study has been conducted to evaluate the 226Ra bioaccumulation among aquatic plants growing in the stream/river adjoining the uranium mining and ore-processing complex at Jaduguda, India. Two types of plant group have been investigated namely free floating algal species submerged into water and plants rooted in stream and riverbed. The highest 226Ra activity concentration (9850 Bq kg-1) was found in filamentous algae growing in the residual water of tailings pond. The concentration ratios of 226Ra in filamentous algae (activity concentration of 226Ra in plant Bq kg-1 fresh weight/activity concentration of 226Ra in water Bq l-1) widely varied i.e. from 1.1 x 103 to 8.6 x 104. Other aquatic plants were also showing wide variability in the 226Ra activity concentration. The ln-transformed filamentous algae 226Ra activity concentration was significantly correlated with that of ln-transformed water concentration (r = 0.89, p 226Ra in stream/riverbed rooted plants and the substrate. For this group, correlation between 226Ra activity concentration and Mn, Fe, Cu concentration in plants were statistically significant.

  8. An assessment of plant biointrusion at the Uranium Mill Tailings Remedial Action Project rock-covered disposal cells

    Energy Technology Data Exchange (ETDEWEB)

    1990-10-01

    This study is one of a number of special studies that have been conducted regarding various aspects of the Uranium Mill Tailings Remedial Action (UMTRA) Project. This special study was proposed following routine surveillance and maintenance surveys and observations reported in a special study of vegetative covers (DOE, 1988), in which plants were observed growing up through the rock erosion layer at recently completed disposal cells. Some of the plants observed were deep-rooted woody species, and questions concerning root intrusion into disposal cells and the need to control plant growth were raised. The special study discussed in this report was designed to address some of the ramifications of plant growth on disposal cells that have rock covers. The NRC has chosen rock covers over vegetative covers in the arid western United States because licenses cannot substantiate that the vegetative covers will be significantly greater than 30 percent and preferably 70 percent,'' which is the amount of vegetation required to reduce flow to a point of stability.'' The potential impacts of vegetation growing in rock covers are not addressed by the NRC (1990). The objectives, then, of this study were to determine the species of plants growing on two rock-covered disposal cells, study the rooting pattern of plants on these cells, and identify possible impacts of plant root penetration on these and other UMTRA Project rock-covered cells.

  9. An assessment of plant biointrusion at the Uranium Mill Tailings Remedial Action Project rock-covered disposal cells

    International Nuclear Information System (INIS)

    This study is one of a number of special studies that have been conducted regarding various aspects of the Uranium Mill Tailings Remedial Action (UMTRA) Project. This special study was proposed following routine surveillance and maintenance surveys and observations reported in a special study of vegetative covers (DOE, 1988), in which plants were observed growing up through the rock erosion layer at recently completed disposal cells. Some of the plants observed were deep-rooted woody species, and questions concerning root intrusion into disposal cells and the need to control plant growth were raised. The special study discussed in this report was designed to address some of the ramifications of plant growth on disposal cells that have rock covers. The NRC has chosen rock covers over vegetative covers in the arid western United States because licenses cannot substantiate that the vegetative covers ''will be significantly greater than 30 percent and preferably 70 percent,'' which is the amount of ''vegetation required to reduce flow to a point of stability.'' The potential impacts of vegetation growing in rock covers are not addressed by the NRC (1990). The objectives, then, of this study were to determine the species of plants growing on two rock-covered disposal cells, study the rooting pattern of plants on these cells, and identify possible impacts of plant root penetration on these and other UMTRA Project rock-covered cells

  10. Root uptake of uranium (6) in solution by a higher plant: speciation in hydroponic solution, bioavailability, micro-localisation and biological effects induced; Transfert racinaire de l'uranium (6) en solution chez une plante superieure: speciation en solution hydroponique, prise en charge par la plante, microlocalisation et effets biologiques induits

    Energy Technology Data Exchange (ETDEWEB)

    Laroche, L

    2005-01-15

    Uranium exists naturally in the environment, usually present in trace quantities. In soil solution and oxic conditions, uranium is present in the +VI oxidation state and forms a large number of inorganic and organic complexes. The exposure medium, an artificial soil solution, was designed in such a way as to control the uranium species in solution. The geochemical speciation code JCHESS was used to calculate the uranium aqueous species concentration and to define the domains of interest, each of them characterized by a limited number of dominant U species. These domains were defined as follows: pH 4.9 with uranyl ions as dominant species, pH 5.8 with hydroxyl complexes and pH 7 where carbonates play a major role. For each pH, short-duration (5 hours of exposure) well-defined laboratory experiments were carried out with Phaseolus vulgaris as plant model. The effect of competitive ions such as Ca{sup 2+} or the presence of ligands such as phosphate or citrate on root assimilation efficiency was explored. Results have shown that uranium transfer was not affected by the presence of calcium, phosphate or citrate (but was decreased of 60% with citrate (10 {mu}M) at pH 5.8) in our experimental conditions. Moreover, observation in Transmission Electronic Microscopy (TEM), equipped with an EDAX probe, have shown that uranium was associated with granules rich in phosphorus and that there were some chloroplast anomalies. Finally, the presence of uranium affects root CEC by reducing it and stimulates root elongation at low uranium concentrations (100 nM, 400 nM and 2 {mu}M at pHs 4.9, 5.8 and 7 respectively) and inhibits it at high uranium concentrations. (author)

  11. Automatic analysis of uranium-bearing extracts in amine solvent extraction plants processing sulfate leach liquors

    International Nuclear Information System (INIS)

    Instrumentation based on continuous segmented flow analysis is suggested for the control of uranium loading in the amine phase of solvent extraction processing sulfate leach liquors. It can be installed with relatively little capital outlay and operational costs are expected to be low. The uranium(VI) in up to 60 samples of extract (proportional 0.1 to 5 g l-1 U) per hour can be determined. Application of spectrophotometry to the analysis of various process streams is discussed and it is concluded that it compares favourably in several important respects with the use of alternative techniques. (orig.)

  12. Uranium enrichment in South Africa: from the world-unique Z-plant to the use of high-technology lasers

    International Nuclear Information System (INIS)

    A historical discussion of the technology used in South Africa for the enrichment of uranium, as well as other technological spin-offs for the country that followed from the construction of the Z-plant. The national energy strategy and objectives of the government during the Apartheid years resulted in the development of several large-scale energy projects. The pressure of sanctions forced the Z-plant to be rushed into operation at an uneconomical capacity of 250 000 SWU per annum. In 1994 this implied that enriched uranium was produced at a cost of $200 per SWU while the world market price was below $90. While the production of enriched uranium at the Z-plant ceased early in 1995, the expertise gained will not be lost entirely. As a result of the high energy and financial capital intensive current methods of producing enriched uranium, research started in the early 1970's into alternative production processes making use of lasers. South Africa has opted for the MLIS (molecular laser isotope separation) process, as a result of its vast experience gained from the Z-plant in the handling of the molecular input gas UF6 (uranium hexafluoride), and this has been under development since the early 1980's. During 1994 significant progress was made with MLIS, in particular with single-step enrichment from natural uranium to better than 4% uranium 235 on a macro scale. The Atomic Energy Corporation of South Africa's strategy is to licence the process internationally. 3 tabs., 3 figs

  13. Uranium enrichment

    International Nuclear Information System (INIS)

    This paper reports that in 1990 the Department of Energy began a two-year project to illustrate the technical and economic feasibility of a new uranium enrichment technology-the atomic vapor laser isotope separation (AVLIS) process. GAO believes that completing the AVLIS demonstration project will provide valuable information about the technical viability and cost of building an AVLIS plant and will keep future plant construction options open. However, Congress should be aware that DOE still needs to adequately demonstrate AVLIS with full-scale equipment and develop convincing cost projects. Program activities, such as the plant-licensing process, that must be completed before a plant is built, could take many years. Further, an updated and expanded uranium enrichment analysis will be needed before any decision is made about building an AVLIS plant. GAO, which has long supported legislation that would restructure DOE's uranium enrichment program as a government corporation, encourages DOE's goal of transferring AVLIS to the corporation. This could reduce the government's financial risk and help ensure that the decision to build an AVLIS plant is based on commercial concerns. DOE, however, has no alternative plans should the government corporation not be formed. Further, by curtailing a planned public access program, which would have given private firms an opportunity to learn about the technology during the demonstration project, DOE may limit its ability to transfer AVLIS to the private sector

  14. Study of internal exposure to uranium compounds in fuel fabrication plants in Brazil

    International Nuclear Information System (INIS)

    The International Commission on Radiological Protection (ICRP) Publication 66 and Supporting Guidance 3) strongly recommends that specific information on lung retention parameters should be used in preference to default values wherever appropriate, for the derivation of effective doses and for bioassay interpretation of monitoring data. A group of 81 workers exposed to UO2 at the fuel fabrication facility in Brazil was selected to evaluate the committed effective dose. The workers were monitored for determination of uranium content in the urinary and faecal excretion. The contribution of intakes by ingestion and inhalation were assessed on the basis of the ratios of urinary to fecal excretion. For the selected workers it was concluded that inhalation dominated intake. According to ICRP 66, uranium oxide is classified as insoluble Type S compound. The ICRP Supporting Guidance 3 and some recent studies have recommended specific lung retention parameters to UO2. The solubility parameters of the uranium oxide compound handled by the workers at the fuel fabrication facility in Brazil was evaluated on the basis of the ratios of urinary to fecal excretion. Excretion data were corrected for dietary intakes. This paper will discuss the application of lung retention parameters recommended by the ICRP models to these data and also the dependence of the effective committed dose on the lung retention parameters. It will also discuss the problems in the interpretation of monitoring results, when the worker is exposed to several uranium compounds of different solubilities. (author)

  15. Bioaccumulation of 226Ra in the plants growing near uranium facilities

    Czech Academy of Sciences Publication Activity Database

    Tykva, Richard; Podracká, Eva

    Warsaw : Warsaw University, 2005. s. 13. [Conference: Mechanism of radionuclides and heavy metals bioaccumulation and their relevance for biomonitoring . 07.10.2005-08.10.2005, Warsaw] Institutional research plan: CEZ:AV0Z40550506 Keywords : bioaccumulation * 226Ra in soil * uranium facilities Subject RIV: DL - Nuclear Waste, Radioactive Pollution ; Quality

  16. Non-destructive assay system for uranium and plutonium in input dissolver solution of Tokai Reprocessing Plant

    International Nuclear Information System (INIS)

    A nondestructive assay system for the accountability of uranium and plutonium in input dissolver solution of a nuclear reprocessing plant, named 'Richman's Densitometer', has been developed at the Tokai Reprocessing Plant (TRP). The development of this system has been carried out as a part of Japan Support Program for Agency Safeguards (JASPAS). The system was designed, based upon the information of the Hybrid K-edge/XRF Densitometer presented by Ottmar et al., KfK. The instrument, composed of an X-ray generator, detectors, collimators and flow-type cells, was compactly designed and has been installed in a shielded cell. It has been confirmed that the precision for determining uranium concentration (approx. 180 g/l) by K-edge densitometer is 0.2% for 1000sec. counting, whereas XRF for plutonium (approx. 1.5 g/l) performs 1.7% of precision for 3000sec. counting. Further, the system was improved for obtain within 1% of plutonium measurement precision. (author)

  17. Simulation study for purification, recovery of plutonium and uranium from plant streams of Fast Reactor Fuel Reprocessing Plant

    International Nuclear Information System (INIS)

    A method for removal of plutonium from the lean organic streams obtained after co-stripping of uranium -plutonium was developed. Plutonium from lean organic phase was stripped using U4+/hydrazine as the stripping agent. The effect of concentrations of stripping agent U4+ and feed Pu concentration in the lean organic phase was studied. Lean organic phases having higher plutonium concentration require three stages of stripping to bring plutonium concentration 4+ stabilized by hydrazine reduces Pu (IV) to Pu (III) thereby stripping plutonium from the organic phase. The non-extractability of Pu (III) by TBP was utilized for development of flow sheet for obtaining a uranium product lean of plutonium for ease of handling. (author)

  18. Root uptake of uranium (6) in solution by a higher plant: speciation in hydroponic solution, bioavailability, micro-localisation and biological effects induced

    International Nuclear Information System (INIS)

    Uranium exists naturally in the environment, usually present in trace quantities. In soil solution and oxic conditions, uranium is present in the +VI oxidation state and forms a large number of inorganic and organic complexes. The exposure medium, an artificial soil solution, was designed in such a way as to control the uranium species in solution. The geochemical speciation code JCHESS was used to calculate the uranium aqueous species concentration and to define the domains of interest, each of them characterized by a limited number of dominant U species. These domains were defined as follows: pH 4.9 with uranyl ions as dominant species, pH 5.8 with hydroxyl complexes and pH 7 where carbonates play a major role. For each pH, short-duration (5 hours of exposure) well-defined laboratory experiments were carried out with Phaseolus vulgaris as plant model. The effect of competitive ions such as Ca2+ or the presence of ligands such as phosphate or citrate on root assimilation efficiency was explored. Results have shown that uranium transfer was not affected by the presence of calcium, phosphate or citrate (but was decreased of 60% with citrate (10 μM) at pH 5.8) in our experimental conditions. Moreover, observation in Transmission Electronic Microscopy (TEM), equipped with an EDAX probe, have shown that uranium was associated with granules rich in phosphorus and that there were some chloroplast anomalies. Finally, the presence of uranium affects root CEC by reducing it and stimulates root elongation at low uranium concentrations (100 nM, 400 nM and 2 μM at pHs 4.9, 5.8 and 7 respectively) and inhibits it at high uranium concentrations. (author)

  19. The behavior of uranium in the soil/plant system with special consideration of the uranium input by mineral phosphorus fertilizer; Untersuchungen zum Verhalten von Uran im System Boden/Pflanze unter besonderer Beruecksichtigung des Uran-Eintrags durch mineralische Phosphorduenger

    Energy Technology Data Exchange (ETDEWEB)

    Setzer, Sascha

    2014-03-28

    The fate of uranium in the environment and, consequently, its hazard potential for human beings is still discussed controversially in the scientific literature. Mineral phosphorous fertilizer can contain uranium as impurity, so that their application can cause an additional input of uranium into agricultural environments. It is still unclear whether and to what extent fertilizer-derived uranium can enter the human food chain by the consumption of contaminated waters or vegetable crop products. The mobility and availability of uranium in the agricultural ecosystem is mainly determined by its behavior in the pedosphere. Due to interactions with organic and inorganic components, the pedosphere is an effective storage and filter system for pollutants and thus plays an important role for the fate of uranium in the environment. In order to improve the assessment of the hazard potential, the present study investigates the behavior of uranium in the soil/plant-system with a focus on the uranium input by mineral phosphorous fertilizer. The specific objectives were (A) to investigate the general distribution of uranium in soils, (B) to determine the effect of CaCO{sub 3} on the sorption behavior of uranium and to quantify the effects of (C - D) varying substrate properties and (E) the application of phosphorus fertilizers on the uranium uptake by ryegrass. The results of these experiments imply that the use of mineral phosphorous fertilizers does not pose an acute risk within the meaning of consumer protection. The studied soils predominantly had a high to very high sorption capability for uranium. At the same time, a small soil-to-plant-transfer of uranium was determined, where the majority of uranium accumulated in/to the plant roots. The availability of uranium in soils and its uptake by plants can thus be classified as generally low. Furthermore, some soil parameters were identified which seem to favor a higher uranium-availability. This study found that very high and

  20. Study on Evaluation of Project Management Data for Decommissioning of Uranium Refining and Conversion Plant - 12234

    International Nuclear Information System (INIS)

    Some of nuclear facilities that would no longer be required have been decommissioned in JAEA (Japan Atomic Energy Agency). A lot of nuclear facilities have to be decommissioned in JAEA in near future. To implement decommissioning of nuclear facilities, it was important to make a rational decommissioning plan. Therefore, project management data evaluation system for dismantling activities (PRODIA code) has been developed, and will be useful for making a detailed decommissioning plan for an object facility. Dismantling of dry conversion facility in the uranium refining and conversion plant (URCP) at Ningyo-toge began in 2008. During dismantling activities, project management data such as manpower and amount of waste generation have been collected. Such collected project management data has been evaluated and used to establish a calculation formula to calculate manpower for dismantling equipment of chemical process and calculate manpower for using a green house (GH) which was a temporary structure for preventing the spread of contaminants during dismantling. In the calculation formula to calculate project management data related to dismantling of equipment, the relation of dismantling manpower to each piece of equipment was evaluated. Furthermore, the relation of dismantling manpower to each chemical process was evaluated. The results showed promise for evaluating dismantling manpower with respect to each chemical process. In the calculation formula to calculate project management data related to use of the GH, relations of GH installation manpower and removal manpower to GH footprint were evaluated. Furthermore, the calculation formula for secondary waste generation was established. In this study, project management data related to dismantling of equipment and use of the GH were evaluated and analyzed. The project management data, manpower for dismantling of equipment, manpower for installation and removal of GH, and secondary waste generation from GH were considered

  1. Individual monitoring of internal exposure to uranium oxides in two fuel fabrication plants

    International Nuclear Information System (INIS)

    Individual monitoring of personal exposure to inhalation of uranium oxides throughout the manufacture of fuel for pressurized water reactor (PWR) includes lung gamma-spectrometry, fecal analysis and urine analysis. Examination of the results shows the following: internal exposure is the consequence of repeated intake incidents as revealed by early peaks of urinary and particularly fecal elimination; a shift is often observed with the results of aerosol concentration measured through air collectors; the measured variations of uranium lung incorporations are relatively fast (apparent mean period 165 d). Correct evaluation of the effective dose equivalent from inhalation requires further information concerning the aerosol size distribution at work stations, the physico-chemical characteristics of the product leading to an estimate of its actual biological solubility, and the measurement of the fraction of aerosol liable to intake with an individual portable collector

  2. Extraction of uranium from the concentrated brine rejected by integrated nuclear desalination plants

    International Nuclear Information System (INIS)

    This work was carried out under the specific collaboration agreement between the Bhabha Atomic Research Centre (BARC) from India and the Commissariat a l'Energie Atomique (CEA) from France. This paper summarises first results of review and research on the possible extraction of uranium from the concentrated brine rejected by integrated nuclear desalination systems, which both partners are currently developing in the two organisations. Three innovative and efficient methods of uranium extraction have been proposed: 1) Resin grafted with calixarene: this method has the advantage of very high selectivity. Its performances, especially for large-scale extraction, still need further R and D and optimisation; 2) Magnetic separations: yet another method with high selectivity, easy separation and affording high degree of material recovery. The method, however, is in developmental stage; 3) Canal system with Braid adsorbents: high selectivity. Appears to be feasible in conjunction with existing technology. It would nonetheless require large amounts of adsorbents and adequate infrastructure. (authors)

  3. Summary of active test of uranium-plutonium co-denitration facility at Rokkasho reprocessing plant

    International Nuclear Information System (INIS)

    The aim of this report is to explain and discuss the active test results in the uranium-plutonium (U-Pu) co-denitration facility. We had previously performed the uranium test with depleted uranium from February of 2005 to January of 2006. Then, the active test has been in progress since March of 2006 toward the start of commercial operation. Plutonium nitrate (PuN) and uranium nitrate hexahydrate (UNH) are mixed at the ratio of approximately 1:1 from the non-proliferation viewpoint. The mixed solution is supplied into the denitration dish inside the denitration oven where the solution is denitrated by microwave heating and converted to MOX powder (PuO2-UO3). After denitration, the powder is converted to the product of MOX powder (PuO2-UO2) through some heating processes and stored in temporary canisters. The powder is transferred to the blender, and then filled into powder cans. 3 powder cans are packed into a canister and transferred to storage in the co-denitrated product powder storage building. Confirmation of the denitration ability of the mixed solution and characteristics of the product powder, (1) Stable and continuous operation in the target period, (2) Characteristics of the product powder, (3) Processing ability at each process, (4) Impurities in the product powder. The test results of the last step of the active test of the U-Pu co-denitration facility are presented; (1) Average throughput in 5 days at A and B lines was more than the target value. (2) Mean particle sizes and specific surface areas in MOX powder were within the standards. (3) Each process indicated good result. (4) Impurities in product powder were less than each limitation. (author)

  4. Physiolgical and ecological studies of the vegetation on ore deposits, 3; Radioecological symptoms of plants over uranium ore deposits in Koisan, Korea

    International Nuclear Information System (INIS)

    From 1975 to 1981, the survey was carried out to find out radioecological effects of uranium ore deposits on natural vegetation in Koisan, Korea. The symptoms of spotty and mosaic chlorosis, and necrosis were observed in flowering plants in the areas of uranium ore deposits at Deok-Peung-Ri A, B, and C in Koisan. Although 13 species were found to be chlorosis and necrosis, foliages observed are small and very rare. The features of these symptoms closely resemble those occured by the effects of heavy metals. The amount of transparent radiation throughout the depth of soils from uranium radiation sources decreases exponentially. The mean contents in leaves of spotty and mosaik chlorotic plants, and soils were 1.36∼1.53 and 5.3∼7.4ppm, respectively

  5. Uranium enrichment

    International Nuclear Information System (INIS)

    Canada is the world's largest producer and exporter of uranium, most of which is enriched elsewhere for use as fuel in LWRs. The feasibility of a Canadian uranium-enrichment enterprise is therefore a perennial question. Recent developments in uranium-enrichment technology, and their likely impacts on separative work supply and demand, suggest an opportunity window for Canadian entry into this international market. The Canadian opportunity results from three particular impacts of the new technologies: 1) the bulk of the world's uranium-enrichment capacity is in gaseous diffusion plants which, because of their large requirements for electricity (more than 2000 kW·h per SWU), are vulnerable to competition from the new processes; 2) the decline in enrichment costs increases the economic incentive for the use of slightly-enriched uranium (SEU) fuel in CANDU reactors, thus creating a potential Canadian market; and 3) the new processes allow economic operation on a much smaller scale, which drastically reduces the investment required for market entry and is comparable with the potential Canadian SEU requirement. The opportunity is not open-ended. By the end of the century the enrichment supply industry will have adapted to the new processes and long-term customer/supplier relationships will have been established. In order to seize the opportunity, Canada must become a credible supplier during this century

  6. Developing new techniques for detecting undeclared nuclear material and activities: UF6 cylinder tracking system for uranium enrichment plants

    International Nuclear Information System (INIS)

    During the uranium enrichment processes conducted in a gas centrifuge or gaseous diffusion enrichment plant, handling and storage of uranium hexafluoride (UF6) is accomplished through the use of cylinders. This includes all UF6 delivered to an enrichment facility, introduced into the cascade, withdrawn as product and shipped to the customer, withdrawn as tails and stored, and material that is sampled for analysis. Current methods used to track UF6 cylinders require extensive manual entry of tracking/accountability data by operators. This manual entry is subject to transcription error and delays in timeliness and requires labor-intensive inventory procedures. Therefore, a need exists for real-time systems to automate this function to improve efficiency and effectiveness and to mitigate the risk of incorrectly entered or improperly manipulated data. A system that provided reliable, accurate, and automated cylinder identification could greatly improve the efficiency in maintaining a facility's inventory of nuclear material, support international safeguards, and increase the probability of earlier detection of UF6 diversion and undeclared production activities. The key to a more effective and efficient material accountability system is the development of a reliable, automated, tamper-resistant process for tagging and monitoring the location and status of UF6 cylinders. This document proposes the use of a cylinder tracking system (CTS) to reduce the risk of false or incorrectly reported cylinder tare weights, diversion of nuclear material, concealment of excess production, use of undeclared cylinders, and misrepresentation of cylinder contents. The suggested system should include the capability to track UF6 cylinders within uranium enrichment process areas. Additionally, a CTS could have the flexibility to incorporate other process data points as well as alarms and/or processing interlocks to detect and prevent abnormal operational conditions that are indicators of

  7. Estimation of uranium isotopes in soil affected by Fukushima nuclear power plant accident and its mobility based on distribution coefficient and soil properties

    Energy Technology Data Exchange (ETDEWEB)

    Sahoo, S.K. [National Institute of Radiological Sciences (Japan); Mishra, S. [Bhabha Atomic Research Centre (India); Sorimachi, A.; Hosoda, M.; Tokonami, S. [Hirosaki University (Japan); Kritsananuwat, R. [Tokyo Metropolitan University (Japan); Ishikawa, T. [Fukushima Medical University (Japan)

    2014-07-01

    An extraordinary earthquake of magnitude 9.0 followed by Tsunami on 11 March 2011 caused serious nuclear accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) about 250 km north to Tokyo, capital of Japan. This resulted in radioactive contamination due to deposition of long-lived radionuclides. Contaminated soil can cause an enhanced radiation exposure even after many years. Depending upon environmental conditions radionuclides can be mobilized to aquatic systems. Therefore, the fate and transfer of these radionuclides in the soil water system is very important for radiation protection and dose assessment. In the present study, emphasis has been given on isotope ratio measurement of uranium that may give some idea about its contamination during accident. Soil and water samples were collected from contaminated areas around FDNPP. Inductively coupled plasma mass spectrometry (ICPMS) is used for total uranium concentration and thermal ionization mass spectrometry (TIMS) has been used for uranium isotopes measurement. Extraction chromatography has been used for the separation of uranium. We have observed, isotope ratio {sup 235}U/{sup 238}U is of natural origin, however in a few soil samples {sup 236}U has been detected. For the migration behavior, its distribution coefficient (K{sub d}) has been determined using laboratory batch method. Depleted uranium is used as tracer for uranium K{sub d} estimation. Chemical characterization of soil with respect to different parameters has been carried out. The effect of these soil parameters on distribution coefficient of uranium has been studied in order to explain the radionuclide mobility in this particular area. The distribution coefficient values for uranium are found to vary from 30-35679 L/Kg. A large variation in the distribution coefficient values shows the retention or mobility of uranium is highly dependent on soil characteristics in the particular area. This variation is explained with respect to pH, Fe, Mn

  8. Practical application of the MARSSIM process to the site release of a Uranium Conversion Plant following decommissioning

    International Nuclear Information System (INIS)

    Highlights: • The final stage in the decommissioning process consists of releasing a site. • Release criteria were set up using site-specific parameters. • We describe the practical application of MARSSIM procedures. • Final status survey results showed that the release criteria were satisfied. - Abstract: The final stage in the decommissioning process consists of releasing a site and a building from regulatory control. In this study, we describe the practical application of MARSSIM process in performing a site remediation and conducting a final status survey and discuss the lessons learned. The release criterion for the site and the building were set up using site-specific parameters that were calculated using RESRAD and RESRAD-Build codes. The planning stage of the final status survey consisted of classifying the site, identifying the survey units and selecting the background reference area using the DQO process. The planning, implementation and assessment of the final status survey for the site and the building of the Uranium Conversion Plant were carried out to demonstrate that residual radioactivity levels meet the release criterion. The null hypothesis must reject in order to demonstrate the objective, null hypothesis is that residual radioactivity in the survey unit exceed the release criterion. The survey results containing the hot spots in the building, a nonparametric statistical test (Wilcoxon Rank Sum) was chosen for assessment due to the presence of the uranium contamination in background soil. The final status survey results showed that the release criteria were satisfied

  9. Concentration of gold, sulphide minerals, and uranium oxide minerals by flotation from ores and metallurgical plant products

    International Nuclear Information System (INIS)

    A process is described for the concentration by flotation of gold, gold bearing minerals and uranium oxide minerals from ores and metallurgical plant products. A pulp of a ground ore is agitation conditioned in at least two agitation conditioning stages wherein in at least one stage the pH of the pulp is lowered with an acid agent to within the pH range of about 1.5 to 5.0, and wherein in at least one additional agitation conditioning stage the pH of the pulp is raised to within the pH range of about 6.0 to 11.0 and wherein in at least the last stage prior to flotation at least one collector selected from the group of sulfhydryl anionic collectors is present. Subsequently, the at least two stage agitation conditioned pulp is subjected to flotation to produce a flotation concentrate enriched in at least one of the mineral values from the group consisting of gold, gold bearing minerals and uranium minerals

  10. Determination of uranium concentrations and its activity ratios in coal and fly ash from Philippine coal-fired thermal power plants using ICP-MS and TIMS

    International Nuclear Information System (INIS)

    The specific activity of 238U as a technologically enhanced naturally occurring radioactive material (TENORM) in feed coal, bottom and fly ash samples from four major coal-fired thermal power plants in the Philippines have been measured using high-resolution gamma-ray spectroscopy system equipped with a high-purity germanium (HPGe) detector. The uranium concentration has been determined from same samples using inductively coupled plasma mass spectrometry (ICP-MS). There was a good correlation between the measured uranium using both methods and has been estimated to be 0.98. Uranium from coal, bottom and fly ash samples were chemically separated and activity ratio (234U/238U) and 235U/238U ratio was measured using a thermal ionization mass spectrometer (TIMS). The highest concentration of uranium was found in fly ash and lowest was for feed coal. Uranium isotopic composition plays an important role in studying its biogeochemical behavior and is a good tracer on the sources of uranium in the environment. (orig.)

  11. Rapid determination of trace uranium in liquid wastes from spent nuclear-fuel reprocessing plants. Using on-line solid-phase extraction/electrochemical detection

    International Nuclear Information System (INIS)

    An on-line analysis system using a solid-phase extraction column coupled to electrochemical detection has been developed for the rapid determination of small amounts of uranium in liquid waste samples of spent nuclear-fuel reprocessing plants. A sample solution with a concentration of 3 M HNO3 was loaded onto a column: packed with U/TEVA resin. The interference elements were rinsed by passing 3 M HNO3 through the column. The adsorbed uranium was eluted with 0.1 M HNO3. The eluate was directly introduced into a flow-electrolysis cell. The reduction current of U(VI)→U(V) was monitored and recorded. The uranium concentration was calculated from the relation between the peak current and the concentration of the standard uranium solution. The result of five repeated analyses for a standard solution containing 2.5 μg (0.1 mL at 25 μg mL-1) of uranium was found to be 2.5 ± 0.025 μg (mean ±1σ). The detection limit calculated from 3-times the standard deviation of the background current was 56 ng. The analysis time required for one sample was within 5 min. The recoveries of uranium in actual nuclear waste reprocessing solutions were 92-112%. (author)

  12. Uranium Immobilization in an Iron-Rich Rhizosphere of a Native Wetland Plant from the Savannah River Site under Reducing Conditions

    Science.gov (United States)

    The hypothesis of this study was that iron plaque formed on the roots of wetland plants and their rhizospheres create environmental conditions favorable for iron reducing bacteria that promote the in situ immobilization of uranium. Greenhouse microcosm studies were conducted usin...

  13. Uranium production from phosphates

    International Nuclear Information System (INIS)

    According to estimates of the world's uranium consumption, exploitation of most rich sources is expected by the 1980's. Forecasts show that the rate of uranium consumption will increase towards the end of the century. It is therefore desirable to exploit poor sources not yet in use. In the near future, the most reasonable source for developing uranium is phosphate rock. Uranium reserves in phosphates are estimated at a few million tons. Production of uranium from phosphates is as a by-product of phosphate rock processing and phosphoric acid production; it will then be possible to save the costs incurred in crushing and dissolving the rock when calculating uranium production costs. Estimates show that the U.S. wastes about 3,000 tons of uranium per annum in phosphoric acid based fertilisers. Studies have also been carried out in France, Yugoslavia and India. In Israel, during the 1950's, a small plant was operated in Haifa by 'Chemical and Phosphates'. Uranium processes have also been developed by linking with the extraction processes at Arad. Currently there is almost no activity on this subject because there are no large phosphoric acid plants which would enable production to take place on a reasonable scale. Discussions are taking place about the installation of a plant for phosphoric acid production utilising the 'wet process', producing 200 to 250,000 tons P2O5 per annum. It is necessary to combine these facilities with uranium production plant. (author)

  14. On line spectrophotometry with optical fibers. Application to uranium-plutonium separation in a spent fuel reprocessing plant

    International Nuclear Information System (INIS)

    Optimization of mixer-settler operation for uranium-plutonium separation in the Purex process can be obtained by remote spectrophotometry with optical fibers. Data acquisition on uranium VI, uranium IV and plutonium III is examined in function of acidity and nitrate content of the solution. Principles for on line multicomponent monitoring and mathematical modelization of the measurements are described

  15. Evaluation of a RF-Based Approach for Tracking UF6 Cylinders at a Uranium Enrichment Plant

    International Nuclear Information System (INIS)

    Approved industry-standard cylinders are used globally to handle and store uranium hexafluoride (UF6) feed, product, tails, and samples at uranium enrichment plants. The International Atomic Energy Agency (IAEA) relies on time-consuming physical inspections to verify operator declarations and detect possible diversion of UF6. Development of a reliable, automated, and tamper-resistant system for near real-time tracking and monitoring UF6 cylinders (as they move within an enrichment facility) would greatly improve the inspector function. This type of system can reduce the risk of false or misreported cylinder tare weights, diversion of nuclear material, concealment of excess production, utilization of undeclared cylinders, and misrepresentation of the cylinders contents. This paper will describe a proof-of-concept approach that was designed to evaluate the feasibility of using radio frequency (RF)-based technologies to track individual UF6 cylinders throughout a portion of their life cycle, and thus demonstrate the potential for improved domestic accountability of materials, and a more effective and efficient method for application of site-level IAEA safeguards. The evaluation system incorporates RF-based identification devices (RFID) which provide a foundation for establishing a reliable, automated, and near real-time tracking system that can be set up to utilize site-specific, rules-based detection algorithms. This paper will report results from a proof-of-concept demonstration at a real enrichment facility that is specifically designed to evaluate both the feasibility of using RF to track cylinders and the durability of the RF equipment to survive the rigors of operational processing and handling. The paper also discusses methods for securely attaching RF devices and describes how the technology can effectively be layered with other safeguard systems and approaches to build a robust system for detecting cylinder diversion. Additionally, concepts for off

  16. Preliminary Hazard Analysis applied to Uranium Hexafluoride - UF6 production plant

    International Nuclear Information System (INIS)

    The purpose of this paper is to present the results of the Preliminary hazard Analysis applied to the UF6 Production Process, which is part of the UF6 Conversion Plant. The Conversion Plant has designed to produce a high purified UF6 in accordance with the nuclear grade standards. This Preliminary Hazard Analysis is the first step in the Risk Management Studies, which are under current development. The analysis evaluated the impact originated from the production process in the plant operators, members of public, equipment, systems and installations as well as the environment. (author)

  17. Process for removing firmly attached or dust deposits in plants for handling uranium hexafluoride

    International Nuclear Information System (INIS)

    The deposits of hydrolysis or reduction products of UF6 in the plants for enriching U235 are removed with BrF3. The BrF3 is present in liquid form and covers the plant walls with a film. The deposits of UO2F3 may be converted into UF6 and may thus be released. The reaction mixture is preferably used at a total pressure of up to 130 millibar. (DG)

  18. Biogeochemistry Of Uranium In Plants Associated To Phosphatic Rocks In The Coastal Region Of Syria

    International Nuclear Information System (INIS)

    Investigations demonstrate that background levels of U in plant ash are less than 2 ppm, and plant materials which contains much in excess of this amount are indicative either of local U mineralization, or presence of high background levels of U in the substrate. The aim of this study was to investigate the U concentrations in different plant parts grown in decomposit phosphate rocks in the mountain coastal region of Syria. Mean U concentrations in the soil ranged between 0.44-3.9 ppm in the reference area and 22-92 ppm in the area of outcrop in phosphate rocks. The results showed that low-order plant forms (Funaria, Lycopodium, and pteridium) readily accumulate U, whereas high-order forms accumulate U in certain parts only. The greatest amount of U in flowering plant is concentrated in the roots, followed by leaves, twigs and fruits. Also the results showed that there is a good correlation between U in soil and plant roots. The study demonstrate that Galium canum could be considered a good indicator plant because it was distributed on decomposit phosphate rocks only, and the U concentration in the aerial part was high (84 ppm) and similar to that in the soil. Also lagurus ovatus may be considered as U indicator plant, because it was highly dense on outcrop phosphate rocks, and has a high U concentration in its roots (up to 93 ppm) and aerial parts (up to 33 ppm) compared to U concentrations in roots and aerial parts in the reference area (10.2 and 0.37 ppm respectively). (Authors)

  19. Development of On-line Uranium Enrichment Monitor of Gaseous UF6 for Uranium Enrichment Plant%铀浓缩厂铀丰度在线监测装置研制

    Institute of Scientific and Technical Information of China (English)

    吕学升; 刘国荣; 金惠民; 赵永刚; 郝学元; 李井怀; 应斌; 俞兆飞

    2013-01-01

    An on-line enrichment monitor was developed to measure the enrichment of UF6 flowing through the processing pipes in uranium enrichment plant.A NaI(Tl) detector was used to measure the count rates of the 185.7 keV γ-ray emitted from 235U,and the total quantity of uranium was determined from thermodynamic characteristics of gaseous uranium hexafluoride.The results show that the maximum relative standard deviation is less than 1% when the measurement time is 120 s or more and the pressure is more than 2 kPa in the measurement chamber.Uranium enrichment of gaseous uranium hexafluoride in the output end of cascade can be monitored continuously by using the device.It should be effective for nuclear materials accountability verifications and materials balance verification at uranium enrichment plant.%研制了铀浓缩厂产品端UF6气体235U丰度在线实时监测装置.该装置由NaI(Tl)探测器、脉冲处理器、压力和温度传感器、管道阀门系统等组成,利用NaI(Tl)探测器对测量容器内气态UF6中235U发射的特征γ射线进行测量来得到235U的量,利用传感器对气体温度、压力进行测量,根据理想气体状态方程得到UF6气体中U的总量,从而得到235U丰度.该装置现场应用实验表明:铀丰度在线监测结果相对标准偏差小于1%,与气体质谱计测量结果相对偏差小于1%.

  20. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Oak Ridge Gaseous Diffusion Plant Site

    Energy Technology Data Exchange (ETDEWEB)

    1991-09-01

    In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) technology, with the near-term goal to provide the necessary information to make a deployment decision by November 1992. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. A programmatic document for use in screening DOE sites to locate the U-AVLIS production plant was developed and implemented in two parts (Wolsko et al. 1991). The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were then subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the ORGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use, socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3. Following the site description and additional data requirements, Sec. 4 provides a short, qualitative assessment of potential environmental issues. 37 refs., 20 figs., 18 tabs.

  1. Environmental site description for a Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) production plant at the Oak Ridge Gaseous Diffusion Plant Site

    International Nuclear Information System (INIS)

    In January 1990, the Secretary of Energy approved a plan for the demonstration and deployment of the Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) technology, with the near-term goal to provide the necessary information to make a deployment decision by November 1992. The U-AVLIS process is based on electrostatic extraction of photoionized U-235 atoms from an atomic vapor stream created by electron-beam vaporization of uranium metal alloy. A programmatic document for use in screening DOE sites to locate the U-AVLIS production plant was developed and implemented in two parts (Wolsko et al. 1991). The first part consisted of a series of screening analyses, based on exclusionary and other criteria, that identified a reasonable number of candidate sites. These sites were then subjected to a more rigorous and detailed comparative analysis for the purpose of developing a short list of reasonable alternative sites for later environmental examination. This environmental site description (ESD) provides a detailed description of the ORGDP site and vicinity suitable for use in an environmental impact statement (EIS). The report is based on existing literature, data collected at the site, and information collected by Argonne National Laboratory (ANL) staff during a site visit. The organization of the ESD is as follows. Topics addressed in Sec. 2 include a general site description and the disciplines of geology, water resources, biotic resources, air resources, noise, cultural resources, land use, socioeconomics, and waste management. Identification of any additional data that would be required for an EIS is presented in Sec. 3. Following the site description and additional data requirements, Sec. 4 provides a short, qualitative assessment of potential environmental issues. 37 refs., 20 figs., 18 tabs

  2. Radionuclide uptake by various plants growing on uranium tailings, Elliot Lake, Ontario

    International Nuclear Information System (INIS)

    Detectable levels of Ra-226 (0.2 to 27.6 pCi/g), Ra-223 (<= 0.1 to 4.3 pCi/g) and Pb-210 (0.6 to 6.9 pCi/g) were measured in various species of vegetation growing on various uranium tailings in Elliot Lake. On the other hand levels of Th-232 (<= 0.1 pCi/g), Th-230 (<= 0.1 pCi/g) were near detection limits in the same vegetation samples. In tailings substrates, all radionuclides investigated were detectable: Ra-226 (8.8 to 552 pCi/g), Ra-223 (3.1 to 213 pCi/g), Pb-210 (5.4 to 441 pCi/g), Th-232 (1.6 to 15.4 pCi/g), Th-230 (4.9 to 62 pCi/g) and Th-228 (1.3 to 38 pCi/g). Lower Th than Ra and Pb levels in tailings substrate were believed to be the cause for the relatively lower Th levels measured in vegetation when compared to Ra and Pb concentrations. No correlation was observed between the level of a given radionuclide in tailings and in the vegetation growing on that tailings

  3. Simulation of a complex chemical plant taking the example of uranium-plutonium extraction

    International Nuclear Information System (INIS)

    The first extraction cycle of a reprocessing plant is simulated by means of the ABAS program system. A program-orientated modular arranged simulation system is presented and described with ABAS which is suitable for the simulation of stationary as well as instationary operation states of engineering plants. The program system can be flexibly applied and independently of computers by using the FORTRAN program language. The functioning ABAS is demonstrated by the example of the reprocessing plant of Eurochemic in Mol, Belgium which works according to the Purex process. The stationary concentration profile in the pulsed sieve diaphragm extraction column of this plant are calculated using the Backflow model. The agreement of the results with the operational data is good if one takes the deficiencies into account when determining the model parameters and equilibrium relationships applied. In the simulation of the transient behaviour of the plant, in the start-up procedure and in accidents, concentration maxima can arise as a result of competing extraction of the components taking part, which are not observed in systems only having one extractable component. (orig.)

  4. Uranium conversion and enrichment

    International Nuclear Information System (INIS)

    A description is given of the Atomic Energy Corporation's uranium conversion and enrichment plants at Valinda ba, including a brief discussion of problems encountered and plans for future developments. (author)

  5. Investigation of molybdenum content reduction in uranium Leach Liquor by using activated Charcoal in Bandar Abbas plant

    International Nuclear Information System (INIS)

    In this work, the possibilities of molybdenum content reduction in uranium leach liquor was investigated by adsorption techniques. Several activated charcoals were used as adsorbents. Under the optimized condition, 83.59% of molybdenum was adsorbed with Norit PK 0.25-1activated charcoal. Since the low uranium adsorption is the aim of this work, by performing the optimization conditions, the uranium adsorption with activated charcoal was determined to be 2.74%.

  6. Bois-Noirs ore. Recovery of uranium of solutions from acid treatment. Results of industrial tests at the Gueugnon plant

    International Nuclear Information System (INIS)

    Industrial-scale tests are reported of the efficiency of two recovery processes for the separation of uranium from sulfuric acid pickling solutions used on ore from Bois-Noirs, at the Gueugnon works. The final stage of each process is sodium uranate. The earlier part of the report deals with tests of the separation of uranium from foreign metals by fractional precipitation. The second part deals with the separation of uranium from these metals by carbonation of the solutions. (author)

  7. Transportation environmental safety analysis of the commercial movement of low enriched uranium (LEU) from DOE sites to the Oak Ridge Y-12 Plant

    International Nuclear Information System (INIS)

    This report documents the technical basis for evaluating the environmental impacts of transporting three metric tons (MTU) of Low Enriched Uranium (LEU) by commercial carrier from DOE sites to the Oak Ridge Y-12 Plant located in Tennessee. The RADTRAN 4 computer code and the HIGHWAY 3.1 computer routing program developed by Sandia National Laboratories and Oak Ridge National Laboratory respectively, were the primary tools utilized in this analysis. The information contained within this report is supplemental to the transportation analysis conducted in the Environmental Assessment for the Proposed Interim Storage of Enriched Uranium Above the Maximum Historical Storage Level at the Y-12 Plant Oak Ridge, Tennessee (DOE-EA/0929). The results of this analysis indicate that the radiological consequences imposed under both incident-free and accident conditions are extremely small and readily meet the goals as set forth in SEN-35-91

  8. Process for removal of adhering or dust deposits in plants handling uranium hexafluoride

    International Nuclear Information System (INIS)

    Deposits containing oxygen, of the type UO2F2 or its hydrate are removed in a UF6 plant by this process. The deposits are first treated with gaseous BBr3 or PBr and then with fluorine, iodine heptafluoride or other halogen fluorides. (DG)

  9. Behavior and Distribution of Heavy Metals Including Rare Earth Elements, Thorium, and Uranium in Sludge from Industry Water Treatment Plant and Recovery Method of Metals by Biosurfactants Application

    OpenAIRE

    Lidi Gao; Naoki Kano; Yuichi Sato; Chong Li; Shuang Zhang; Hiroshi Imaizumi

    2012-01-01

    In order to investigate the behavior, distribution, and characteristics of heavy metals including rare earth elements (REEs), thorium (Th), and uranium (U) in sludge, the total and fractional concentrations of these elements in sludge collected from an industry water treatment plant were determined and compared with those in natural soil. In addition, the removal/recovery process of heavy metals (Pb, Cr, and Ni) from the polluted sludge was studied with biosurfactant (saponin and sophorolipid...

  10. Business Plan Analysis of a New Reverse Osmosis Plant at a Uranium Mine, the Rabbit Lake Operation-Eagle Point Mine

    OpenAIRE

    Khosravinejad, Mehran

    2011-01-01

    This thesis provides a prefeasibility justification for a new Reverse Osmosis Water Treatment Plant at Cameco’s Rabbit Lake operation. The economics of the proposed project are discussed in detail including an in-depth explanation of the uranium industry, required capital investment, and expected gains. As well, the potential environmental and social effects of constructing the reverse osmosis facility and extending the life of the Eagle Point mine are examined. After all potential impacts of...

  11. Occupational monitoring in a mine and processing plant of uranium in Brazil

    International Nuclear Information System (INIS)

    This work describes the activities of occupational radiological monitoring of workers from Uranium Concentrate Unit - URA, from 1/1/2003 to 12/31/2003. In this period 1657 Licenses to Work with Radiation (LTR) were issued, covering 4548 workers. 157 of these were visitors and 21 were inspectors. For external exposure the location with the highest dose rate was the stocking DUA, with an average of 3.10 x 10-2 mSv/h, followed by mina (drilling) with 1.13 x 10-2 mSv/h and decontamination with 0.74 x 10-2 mSv/h. With respect to internal exposure the area with the highest dose was the packaging of DUA with 1.33 x 10-2 mSv/h, patio of crushing with 0.40 x 10-2 mSv/h and the leaching patio with 0.36 x 10-2 mSv/h. For external exposure, the operating function which obtained higher dose group was process operator with 2.35 man-mSv, driver with 1.54 man-mSv and servant with 1.13 man-mSv. For internal dose, the function with highest dose group was the drilling helper with 4.28 x 10-1 man-mSv, followed by process operator with 0.46 x 10-1 man-mSv and finally the driver with 10 x 0.22-1 man-mSv

  12. Africanos, tráfico atlántico y cimarrones en las fronteras entre la Guyana Francesa y la América portuguesa, siglo XVIII

    Directory of Open Access Journals (Sweden)

    Flávio dos Santos Gomes

    2011-01-01

    Full Text Available El artículo analiza las experiencias históricas de los cimarrones en un área de fronter atlántica continental entre la Guyana Francesa y la América portuguesa durante el siglo XVII. Las expectativas de los fugitivos africanos se abordan relacionando el movimiento del tráfico atlántico de esclavos-sus variaciones, los volúmenes y las procedencias-. De esta forma se reflexiona sobre los ambientes sociales, étnicos y geográficos que fueron encontrados y recreados en las selvas de estas zonas fronterizas. En un territorio de conflictos, enfrentamientos, disputas coloniales y expectativas de identidades, surgieron espacios de cooperación, donde los colonos europeos y las poblaciones de indígenas y de africanos se reinventaron como culturas y comunidades. Los circuitos demográficos del tráfico atlántico estaban conectados a la experiencia de africanos de diversas procedencias y a la posibilidad de encuentro de estos, a través de las fugas y de las comunidades transétnicas en una zona de frontera transnacional durante la Colonia.

  13. In-situ removal and characterisation of uranium-containing particles from sediments surrounding the Fukushima Daiichi Nuclear Power Plant

    Science.gov (United States)

    Martin, P. G.; Griffiths, I.; Jones, C. P.; Stitt, C. A.; Davies-Milner, M.; Mosselmans, J. F. W.; Yamashiki, Y.; Richards, D. A.; Scott, T. B.

    2016-03-01

    Traditional methods to locate and subsequently study radioactive fallout particles have focused heavily on autoradiography coupled with in-situ analytical techniques. Presented here is the application of a Variable Pressure Scanning Electron Microscope with both backscattered electron and energy dispersive spectroscopy detectors, along with a micromanipulator setup and electron-hardening adhesive to isolate and remove individual particles before synchrotron radiation analysis. This system allows for a greater range of new and existing analytical techniques, at increased detail and speed, to be applied to the material. Using this method, it was possible to erform detailed energy dispersive spectroscopy and synchrotron radiation characterisation of material likely ejected from the Fukushima Daiichi Nuclear Power Plant found within a sediment sample collected from the edge of the 30 km exclusion zone. Particulate material sub-micron in maximum dimension examined during this work via energy dispersive spectroscopy was observed to contain uranium at levels between 19.68 and 28.35 weight percent, with the application of synchrotron radiation spectroscopy confirming its presence as a major constituent. With great effort and cost being devoted to the remediation of significant areas of eastern Japan affected by the incident, it is crucial to gain the greatest possible understanding of the nature of this contamination in order to inform the most appropriate clean-up response.

  14. Dynamic simulation and verification of a compression-liquefaction system for material withdrawal from a uranium-enrichment plant

    International Nuclear Information System (INIS)

    Dynamic simulation was used to evaluate the design of the Tails (depleted 235U assay) Withdrawal System for an uranium enrichment plant. Desirability of a simulation to check the design was indicated by requirements for a very high system reliability (99.95% availability) over a wide range of system throughput (85:1). Objective of the simulation included: evaluate alternate compressor anti-surge schemes, identify control system sensitivities, examine start-up and shut-down procedures, identify system limitations and testing of proposed design changes, and provide an understanding of system behavior. Three levels of process complexity were modeled: (1) compressions system, (2) combined compressor and liquefaction system, and (3) parallel operation of two compression/liquefaction trains. Two compressor train configurations were evaluated with the simulation mode. A FORTRAN based simulation methodology was used to implement and solve the mathematical models and plot the time history behavior for each test run. Results included discovery that that initial process steady state design would not operate stably. A new steady state was formulated which required some modifications to equipment sizing and control system philosophy. This new design was tested and proven with the simulation. Simulation objectives were achieved. Based on the simulation results, recommendations were made regarding: best compressor configuration, most effective anti-surge control scheme, changes to enhance system reliability and operability, control system sensitivities, control system design to achieve load sharing for parallel trains, and overall system operability with existing design

  15. Refurbishment of uranium hexafluoride cylinder storage yards C-745-K, L, M, N, and P and construction of a new uranium hexafluoride cylinder storage yard (C-745-T) at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    The Paducah Gaseous Diffusion Plant (PGDP) is a uranium enrichment facility owned by the US Department of Energy (DOE). A residual of the uranium enrichment process is depleted uranium hexafluoride (UF6). Depleted UF6, a solid at ambient temperature, is stored in 32,200 steel cylinders that hold a maximum of 14 tons each. Storage conditions are suboptimal and have resulted in accelerated corrosion of cylinders, increasing the potential for a release of hazardous substances. Consequently, the DOE is proposing refurbishment of certain existing yards and construction of a new storage yard. This environmental assessment (EA) evaluates the impacts of the proposed action and no action and considers alternate sites for the proposed new storage yard. The proposed action includes (1) renovating five existing cylinder yards; (2) constructing a new UF6 storage yard; handling and onsite transport of cylinders among existing yards to accommodate construction; and (4) after refurbishment and construction, restacking of cylinders to meet spacing and inspection requirements. Based on the results of the analysis reported in the EA, DOE has determined that the proposed action is not a major Federal action that would significantly affect the quality of the human environment within the context of the National Environmental Policy Act of 1969. Therefore, DOE is issuing a Finding of No Significant Impact. Additionally, it is reported in this EA that the loss of less than one acre of wetlands at the proposed project site would not be a significant adverse impact.

  16. Refurbishment of uranium hexafluoride cylinder storage yards C-745-K, L, M, N, and P and construction of a new uranium hexafluoride cylinder storage yard (C-745-T) at the Paducah Gaseous Diffusion Plant, Paducah, Kentucky

    International Nuclear Information System (INIS)

    The Paducah Gaseous Diffusion Plant (PGDP) is a uranium enrichment facility owned by the US Department of Energy (DOE). A residual of the uranium enrichment process is depleted uranium hexafluoride (UF6). Depleted UF6, a solid at ambient temperature, is stored in 32,200 steel cylinders that hold a maximum of 14 tons each. Storage conditions are suboptimal and have resulted in accelerated corrosion of cylinders, increasing the potential for a release of hazardous substances. Consequently, the DOE is proposing refurbishment of certain existing yards and construction of a new storage yard. This environmental assessment (EA) evaluates the impacts of the proposed action and no action and considers alternate sites for the proposed new storage yard. The proposed action includes (1) renovating five existing cylinder yards; (2) constructing a new UF6 storage yard; handling and onsite transport of cylinders among existing yards to accommodate construction; and (4) after refurbishment and construction, restacking of cylinders to meet spacing and inspection requirements. Based on the results of the analysis reported in the EA, DOE has determined that the proposed action is not a major Federal action that would significantly affect the quality of the human environment within the context of the National Environmental Policy Act of 1969. Therefore, DOE is issuing a Finding of No Significant Impact. Additionally, it is reported in this EA that the loss of less than one acre of wetlands at the proposed project site would not be a significant adverse impact

  17. Uranium accumulation by aquatic macrophyte, Pistia stratiotes

    International Nuclear Information System (INIS)

    Uranium accumulation by aquatic macrophyte, Pistia stratiotes from aqueous solution was investigated in laboratory condition. The objective was to evaluate the uranium accumulation potential and adopt the plant in uranium containing medium to improve its uptake capacity. The plant was found to tolerate and grow in the pH range of 3-7. Accumulation of uranium improved with increasing pH and the plant could remove 70% uranium from the medium (20 mg/L) within 24 hours of incubation at pH 5-6. Uptake of uranium on either side of this pH range decreased

  18. Measurement of the enrichment of uranium in the pipework of a gas centrifuge enrichment plant

    International Nuclear Information System (INIS)

    The US and UK have been separately working on the development of a NDA instrument to determine the enrichment of gaseous UF6 at low pressures in cascade header pipework in line with the conclusions of the Hexapartite Safeguards Project viz. the instrument is capable of making a ''go/no go'' decision of whether the enrichment is less than/greater than 20%. Recently, there has been a series of very useful technical exchanges of ideas and information between the two countries. This has led to a technical formulation for such an instrumentation based on γ-ray spectrometry which, although plant-specific in certain features, nevertheless is based on the same physical principles. Experimental results from commercially operating enrichment plants are very encouraging and indicate that a complete measurement including set up time on the pipe should be attainable in about 30 minutes when measuring pipes of diameter around 110 mm. 5 refs., 4 figs

  19. Oxidative stress responses induced by uranium exposure at low pH in leaves of Arabidopsis thaliana plants.

    Science.gov (United States)

    Saenen, Eline; Horemans, Nele; Vanhoudt, Nathalie; Vandenhove, Hildegarde; Biermans, Geert; van Hees, May; Wannijn, Jean; Vangronsveld, Jaco; Cuypers, Ann

    2015-12-01

    Anthropogenic activities have led to a widespread uranium (U) contamination in many countries. The toxic effects of U at the cellular level have mainly been investigated at a pH around 5.5, the optimal pH for hydroponically grown plants. However, since the speciation of U, and hence its toxicity, is strongly dependent on environmental factors such as the pH, it is important to investigate the effects of U at different environmentally relevant pH levels. Although U is poorly translocated from the roots to the shoots, resulting in a low U concentration in the leaves, it has been demonstrated that toxic effects in the leaves were already visible after 1 day exposure at pH 5.5, although only when exposed to relatively high U concentrations (100 μM). Therefore, the present study aimed to analyse the effects of different U concentrations (ranging from 0 to 100 μM) at pH 4.5 in leaves of Arabidopsis thaliana plants. Results indicate that U induces early senescence in A. thaliana leaves as was suggested by a decreased expression of CAT2 accompanied by an induction of CAT3 expression, a decreased CAT capacity and an increased lipid peroxidation. In addition, miRNA398b/c is involved in the regulation of the SOD response in the leaves. As such, an increased MIR398b/c expression was observed leading to a decreased transcript level of CSD1/2. Finally, the biosynthesis of ascorbate was induced after U exposure. This can point towards an important role for this metabolite in the scavenging of reactive oxygen species under U stress. PMID:26263174

  20. 2.5 Mio. m3 decontaminated waste water - successful operation of the treatment plant for waste water from uranium ore mines

    International Nuclear Information System (INIS)

    During the period from 1950 to 1989, approx. 70 million t of uranium ore from the former WISMUT company was processed under Soviet management in the Crossen treatment plant in the former GDR. While the mined uranium was mainly used in nuclear technology in the Soviet Union, the storage of the solid residues contaminated with residual uranium, radium and arsenic at the WISMUT site led to considerable environmental damage over this long period. One of the main aims of WISMUT GmbH, which was newly founded in 1991, is therefore to remediate and recultivate the adsettling plants. Due to the extent of this problem, the processes used must not only prove themselves by showing a high degree of innovation with regard to process engineering, but also by being highly economic. The waste water treatment plant in Helmsdorf, which was planned and erected by Preussag Noell Wassertechnik GmbH, made a major contribution to achieving this objective. Apart from the central plant for degrading the surplus water, which is to be treated to meet the required limits before being discharged into the Zwickauer Mulde, the treatment plant also includes the construction of a plant to immobilize the associated residues. This guarantees that they are deposited in an environmentally acceptable manner. Since starting operation in May 1995, more than 2.5 mio. m3 of waste water had been treated up to the end of 1996. Using the experience gained from more than one year of operation, the throughput, which was planned to be 250 m3/h max., has now been raised by about 10% to 280 m3/h. (orig.)

  1. Vegetation composition and ²²⁶Ra uptake by native plant species at a uranium mill tailings impoundment in South China.

    Science.gov (United States)

    Hu, Nan; Ding, Dexin; Li, Guangyue; Zheng, Jifang; Li, Le; Zhao, Weichao; Wang, Yongdong

    2014-03-01

    A field investigation was conducted for the vegetation composition and (226)Ra uptake by native plant species at a uranium mill tailings impoundment in South China. 80 species belonging to 67 genera in 32 families were recorded in the sampling sites. The Poaceae and Asteraceae were the dominant families colonizing the impoundment. The number of the plant species and vegetation community composition in the sampling sites seemed most closely related to the activities of (226)Ra and the pH value of the uranium tailings. The plant species in the sampling sites with relatively low activities of (226)Ra and relatively high pH value formed a relatively stable vegetation community. The plant species in the sampling sites with medium activities of (226)Ra and medium pH value formed the transitional vegetation community. The plant species in the sampling sites with relatively high activities of (226)Ra and relatively low pH value formed a simple unstable vegetation community that was similar to that on the unused grassland. The activities of (226)Ra and transfer factors (TFs) varied greatly with the plant species. The high activities of (226)Ra and TFs were found in the leaves of Pteris multifida (150.6 Bq/g of AW; 9.131), Pteridium aquilinum (122.2 Bq/g of AW; 7.409), and Dryopteris scottii (105.7 Bq/g of AW; 6.408). They satisfied the criteria for a hyperaccumulator for (226)Ra. They may be the candidates for phytoremediation of (226)Ra in the uranium mill tailings impoundment areas and the contaminated soils around. PMID:24412774

  2. Uranium-mining, grading and nuclear power plants between Wera and Oder-Neisse

    International Nuclear Information System (INIS)

    The gneiss areas in the 'Westerzgebirge' with additional hydrothermal formations belong to the Ag-Co-Ni-Bi-U main formation group. In most cases they are unworkable. This did not deter the Soviet Union from founding there after World War II the Wismut AG for the U-mining for their production of atomic bombs. The other U-mines of the GDR are of low extent. The U-ore grading techniques as well as the radiation safety regulations and sites of nuclear power plants and reactors in the GDR are stated in short. (DG)

  3. Uranium from phosphate ores

    International Nuclear Information System (INIS)

    Phosphate rock, the major raw material for phosphate fertilizers, contains uranium that can be recovered when the rock is processed. This makes it possible to produce uranium in a country that has no uranium ore deposits. The author briefly describes the way that phosphate fertilizers are made, how uranium is recovered in the phosphate industry, and how to detect uranium recovery operations in a phosphate plant. Uranium recovery from the wet-process phosphoric acid involves three unit operations: (1) pretreatment to prepare the acid; (2) solvent extraction to concentrate the uranium; (3) post treatment to insure that the acid returning to the acid plant will not be harmful downstream. There are 3 extractants that are capable of extracting uranium from phosphoric acid. The pyro or OPPA process uses a pyrophosphoric acid that is prepared on site by reacting an organic alcohol (usually capryl alcohol) with phosphorous pentoxide. The DEPA-TOPO process uses a mixture of di(2-ethylhexyl)phosphoric acid (DEPA) and trioctyl phosphine oxide (TOPO). The components can be bought separately or as a mixture. The OPAP process uses octylphenyl acid phosphate, a commercially available mixture of mono- and dioctylphenyl phosphoric acids. All three extractants are dissolved in kerosene-type diluents for process use

  4. METHODS FOR RECONSTRUCTION OF RADIONUCLIDE COMPOSITION AND ACTIVITY OF FISSION PRODUCTS ACCUMULATED IN THE IRRADIATED URANIUM AT THE MOMENT OF ITS RADIOCHEMICAL REPROCESSING AT PLANT “B”, “MAYAK” PA IN THE EARLY 1950s

    Energy Technology Data Exchange (ETDEWEB)

    Glagolenko, Y. V.; Drozhko, Evgeniy G.; Mokrov, Y.; Rovny, Sergey I.; Lyzhkov, A. V.; Anspaugh, L. R.; Napier, Bruce A.

    2008-06-01

    The article describes calculation procedure for reconstruction of radionuclide composition and activity of fission fragments accumulated in the irridated uranium from “Mayak” PA graphite-uranium reactors at the moment, when irradiation is completed, and at the moment, when the uranium is transferred to radiochemical processing (plant B) in the early 1950s. The procedure includes a reactor model and a cooling pool model. It is based on archive data on monthly uranium unloading and loading in the reactor and in the cooling pool of each reactor. The objects of reconstruction include: order of reloading of uranium versus its location radius in the reactor core; duration of irradiation and radionuclide composition of fission fragments for each radius; order of uranium removal from the cooling pool; effective time of uranium storage in the pool; radionuclide composition and activity of fission fragments in the irradiated uranium delivered to radiochemical reprocessing daily and on average for each month. The model is intended for use in reconstruction of parameters of radionuclide release source into the atmosphere and the source of liquid radioactive waste generation at the “Mayak” PA radiochemical plant.

  5. Methods For Reconstruction Of Radionuclide Composition And Activity Of Fission Products Accumulated In The Irradiated Uranium At The Moment Of Its Radiochemical Reprocessing At Plant 'B', 'Mayak' PA In The Early 1950s

    International Nuclear Information System (INIS)

    The article describes calculation procedure for reconstruction of radionuclide composition and activity of fission fragments accumulated in the irradiated uranium from 'Mayak' PA graphite-uranium reactors at the moment, when irradiation is completed, and at the moment, when the uranium is transferred to radiochemical processing (plant B) in the early 1950s. The procedure includes a reactor model and a cooling pool model. It is based on archive data on monthly uranium unloading and loading in the reactor and in the cooling pool of each reactor. The objects of reconstruction include: order of reloading of uranium versus its location radius in the reactor core; duration of irradiation and radionuclide composition of fission fragments for each radius; order of uranium removal from the cooling pool; effective time of uranium storage in the pool; radionuclide composition and activity of fission fragments in the irradiated uranium delivered to radiochemical reprocessing daily and on average for each month. The model is intended for use in reconstruction of parameters of radionuclide release source into the atmosphere and the source of liquid radioactive waste generation at the 'Mayak' PA radiochemical plant.

  6. The ERGO project: uranium from mine tailings

    International Nuclear Information System (INIS)

    This paper describes the ERGO project, in Witwatersrand, for extracting gold, sulphur and low-grade uranium from slime dams resulting from gold mining operations. The design of the plant, feasibility studies, methods of uranium extraction and personnel management are discussed. The profitability of the plant, with uranium recovery at 27%, and prospects of improvement, are noted. (U.K.)

  7. Production of Commercial Uranium Concentrate From El-Sela Shear Zone Mineralized Ore Material, South Eastern Desert - Egypt, At Inshas Pilot Plant Unit

    International Nuclear Information System (INIS)

    This paper is concerned with studying the different processes leading to the production of commercial uranium concentrate (yellow cake) from the mineralized ore material of El-Sela Shear zone, South Eastern Desert, Egypt. Uranium concentrate is produced by the treatment of about 25 tons from the study ore material that assaying about 580 ppmU at Inshas Pilot Plant Unit. In the present work, the studied lab-scale leaching and extraction conditions of the ore material under consideration are shifted to the pilot plant scale. From the latter, an average leaching efficiency exceeding 82% has been achieved. On the other hand, some difficulties being arised during pilot operations such as filtration, settling, washing and huge dilute volumes of the sulfate leach slurry, are overcome through the flocculent addition and reputed concentrations. The pH of prepared pregnant sulfate leach liquor is then adjusted at 1.75 and then shifted to the fixed bed ion exchange resin unit for the extraction of uranium to obtain highly pure concentrate UO4. 2H2O. The latter would be subjected to further purification processes to prepare nuclear fuel.

  8. Construction of a new plant in Gabon by the Compagnie des Mines d'Uranium de Franceville: Three years' experience of operation

    International Nuclear Information System (INIS)

    As part of a programme to modernize and extend its means of production which had already commenced with the setting up of a solvent extraction unit in 1977, and a sulphuric acid production facility of increased capacity (60 t/d) in 1980, the Compagnie des Mines d'Uranium de Franceville (COMUF) started a new uranium ore treatment plant in 1982. The aim was to replace the older installation built in 1959-60, which had reached the limit of its capacity and whose largest equipment was in need of renewal. The new installations are capable of an annual uranium production of 1500 t of magnesium uranate. The techniques adopted were the most modern, those likely to simplify the process and improve operating costs, namely semi-autogenous grinding and solid-liquid separation using band filters. Three years of operating experience confirm the sound choice of the main options made when designing the installations. The treatment performances, especially those which are independent of the nature of the ore, and the reliability of operation are indeed excellent. Thanks to a training programme started in the late 1980s the staff adapted rapidly to the new technical environment and it has been possible to run the entire plant with almost exclusively Gabonese staff. (author). 1 tab

  9. Uranium's transformation from mineral to fuel bundles

    International Nuclear Information System (INIS)

    Uranium undergoes chemical transformation phases before it can be used in the nuclear power plant. In first phase uranium is transformed from mineral to yellow cake, in which uranium is in the form of U3O8. After that comes conversion (U3O8-UF6) and enrichment (0.7%-3% U-235). Finally, uranium is converted in fuel fabrication to uranium dioxide, UO2, and fuel pellets are made

  10. Demographic studies of Sherpalle area, the proposed site for Uranium Processing Plant in Nalgondo district, Andhra Pradesh

    International Nuclear Information System (INIS)

    Availability of nuclear fuel, in the wake of over stress on other power resources, for continuous production of nuclear energy is a crucial and essential factor. Uranium Corporation of India Ltd. (UCIL) is undertaking mining and processing of uranium ore on large scale and it is expanding its operation in the Nalgonda district of AP, which is endowed with huge uranium deposits. To initiate the continuous operation of mining processes, it is essential and prime requisite to generate baseline demographic data which can be compared to both past and future date to identify changes that may result due to mining operations

  11. Measurement of uranium and thorium in coal fly ash and bottom ash samples from a thermal power plant by using a high resolution semiconductor detector

    International Nuclear Information System (INIS)

    A low background γ-ray detection system has been constructed for measuring the natural radioactivity in coal samples. It is based on a high-purity Ge detector mounted within a massive lead shield which reduces the normal background level by a factor of about 20. This makes it possible to measure the low intensity γ-rays from the natural radioactivity present in the samples. Using this equipment uranium and thorium concentrations in coal fly ash and bottom ash samples from a coal fired power plant located at Bathinda, India have been measured. The uranium activity found in the samples is within the range of concentrations observed in other countries while the thorium activity is found to be somewhat higher. (Author)

  12. Concentration of gold, sulphide minerals and uranium oxide minerals by flotation from ores and metallurgical plant products

    International Nuclear Information System (INIS)

    A process for the recovery by froth flotation of gold and mineral values selected from the group consisting of gold bearing minerals, platinum group minerals, silver group minerals, and uranium group minerals, from ores and metallurgical plant products containing at least gold and at least one of the other said minerals comprising: subjecting a suitably prepared pulp of the material to mechanical agitation in at least one agitation conditioning stage wherein the pH of the said pulp has been lowered with an acid agent to an optimum pH point within the pH range of about 1.5 to 5.0 and wherein the agitation conditioning is for a sufficient period of time to bring about heavy activation of at least one of the said mineral values in at least one subsequent mechanical agitation conditioning stage wherein the said pulp is further agitation conditioned for a sufficient period of time and at an optimum pH point in the pH range of about 6.0 to 11.0 in the presence of at least one collector selected from the group of sulfhydryl anionic collectors to produce the said heavy activation of at least gold and at least one of the other said mineral values; and subsequently in the presence of a frother subjecting and said agitation conditioned pulp to flotation to produce a concentrate enriched in gold and at least one of the othersaid mineral values, and a tailings product impoverished in at least gold and at least one of the other said mineral values

  13. Long-term biobarriers to plant and animal intrusions of uranium tailings. [24% trifluralin, 18% carbon black, and 58% polymer

    Energy Technology Data Exchange (ETDEWEB)

    Cline, J.F.; Burton, F.G.; Cataldo, D.A.; Skiens, W.E.; Gano, K.A.

    1982-09-01

    The objective of this project was to develop and evaluate the effectiveness of physical and chemical barriers designed to prevent plant and animal breachment of uranium mill tailings containment systems for an extended period of time. A polymeric carrier/biocide delivery system was developed and tested in the laboratory, greenhouse and field. A continuous flow technique was established to determine the release rates of the biocides from the PCD systems; polymeric carrier specifications were established. Studies were conducted to determine effective biocide concentrations required to produce a phytotoxic response and the relative rates of phytotoxin degradation resulting from chemical and biological breakdown in soils. The final PCD system developed was a pelletized system containing 24% trifluralin, 18% carbon black and 58% polymer. Pellets were placed in the soil at the Grand Junction U-tailings site at one in. and two in. intervals. Data obtained in the field determined that the pellets released enough herbicide to the soil layer to stop root elongation past the barrier. Physical barriers to subsurface movement of burrowing animals were investigated. Small crushed stone (1 to 1 1/2 in. diameter) placed over asphalt emulsion and multilayer soil seals proved effective as barriers to a small mammal (ground squirrels) but were not of sufficient size to stop a larger animal (the prairie dog). No penetrations were made through the asphalt emulsion or the clay layer of the multilayer soil seals by either of the two mammals tested. A literature survey was prepared and published on the burrowing habits of the animals that may be found at U-tailings sites.

  14. An investigation into the upward transport of uranium-series radionuclides in soils and uptake by plants

    International Nuclear Information System (INIS)

    The upward migration of radionuclides in the 238U decay series in soils and their uptake by plants is of interest in various contexts, including the geological disposal of radioactive waste and the remediation of former sites of uranium mining and milling. In order to investigate the likely patterns of behaviour of 238U-series radionuclides being transported upward through the soil column, a detailed soil–plant model originally developed for studying the behaviour of 79Se in soil–plant systems has been adapted to make it applicable to the 238U series. By undertaking a reference case simulation and a series of sensitivity studies, it has been found that a wide variety of behaviour can be exhibited by radionuclides in the 238U decay chain in soils, even when the source term is limited to being a constant flux of either 238U or 226Ra. Hydrological conditions are a primary factor, both in respect of the overall advective flow deeper in the soil, which controls the rate of upward migration, and in the influence of seasonally changing flow directions closer to the soil surface, which can result in the accumulation of radionuclides at specific depths irrespective of changes in sorption between the oxic and anoxic regions of the soil. However, such changes in sorption can also be significant in controlling the degree of accumulation that occurs. This importance of seasonally varying factors in controlling radionuclide transport in soils even in very long-term simulations is a strong argument against the use of annually averaged parameters in long-term assessment models. With a water table that was simulated to fluctuate seasonally from a substantial depth in soil to the surface soil layer, the timing of such variations in relation to the period of plant growth was found to have a major impact on the degree of uptake of radionuclides by plant roots. In long-term safety assessment studies it has sometimes been the practice to model the transport of 226Ra in soil, but to

  15. Uranium conversion

    International Nuclear Information System (INIS)

    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 UF6 and UF4 are present require equipment that is made of corrosion resistant material

  16. Review on phytoremediation of uranium-contaminated environment

    International Nuclear Information System (INIS)

    Phytoremediation, a promising technology using plants to remove radioactive contaminants from the environment or to render them harmless, has become a hot topic in current research. Studies on phytoremediation of uranium-contaminated environment are reviewed with special focuses on several subsets including types of phytoremediation of uranium (such as phytoextraction, rhizofiltration and phytostabilization), influencing factors (such as plant species, soil properties, microorganism, soil amendments, fertilization and uranium speciation) of uranium accumulation by plants, cases studies and trend in phytoremediation of uranium. (authors)

  17. 五种水生植物对水中铀的去除作用%Uranium removal from water by five aquatic plants

    Institute of Scientific and Technical Information of China (English)

    胡南; 丁德馨; 李广悦; 王永东; 李乐; 郑济芳

    2012-01-01

    采用水培实验,研究了浮叶植物野生水葫芦(Eichhornia crassipes)、漂浮植物浮萍(Lemna minor L)、满江红(Azolla imbircata)、沉水植物菹草(Potamogeton crispus)、挺水植物空心莲子草(Alligator Alternanthera Herb)在初始铀浓度分别为0.15、1.50和15.00mg·L-1水中的生长状况及它们对水中铀的去除能力.结果表明,在21d的水培试验期内,满江红对铀表现出了最强的抗性,0.15、1.50和15.00mg·L-1的铀对满江红的生长抑制率分别只有4.56%、2.48%和6.79%,而满江红对水中铀的去除率分别达到了94%、97%和92%.进一步的试验表明,每1L水中种植7.5g满江红,可以获得最大的铀去除率,将初始铀浓度为1.25、2.50、5.00和10.00mg·L-1的水体降至国家排放标准(GB23727-2009)规定值(0.05mg·L-1)以下分别需要17、19、23和25d.研究结果为进一步开展铀污染水体植物修复的研究打下了基础.%Hydroponic solution culture experiments were conducted on the growth of Eichhornia crassipes,Lemna minor L,Azolla imbircata,Potamogeton crispus,and Alligator alternanthera Herb in water with 0.15,1.50 and 15.00 mg · L-1 concentrations of uranium.The uranium removal from the water by the aquatic plants was also examined.For the 21 days of hydroponic solution culture experiments,Azolla imbircata exhibited the strongest resistance to uranium and its growth inhibition rates induced by the water with 0.15,1.50 and 15.00 mg · L-1 concentrations of uranium were 4.56%,2.48%,6.79%,respectively.The uranium removal rates from the water by the plant amounted to 94%,97% and 92%,respectively.Further experiments revealed that the most uranium removal could be achieved when 7.5 g Azolla imbircata was grown in 1 L of water.17,19,23 and 25 days were required for the plant with the uranium concentration in water of 1.25,2.50,5.00 and 10.00 mg · L-1 to reduce to below the national emission standards of China,respectively.The results

  18. Capital and operating costs of irradiated natural uranium reprocessing plants; Couts d'investissement et d'exploitation des usines de retraitement de l'uranium naturel irradie

    Energy Technology Data Exchange (ETDEWEB)

    Thiriet, L.; Jouannaud, C.; Couture, J.; Duboz, J. [Commissariat a l' Energie Atomique (France). Centre d' Etudes Nucleaires; Oger, C. [Saint Gobain Nucleaire (France)

    1966-07-01

    This paper presents first a method of analysing natural uranium reprocessing plants investment costs (method similar to LANG and BACH well known in the fuel oil industry) and their operating costs (analysed according to their economic type). This method helps establishing standard cost structures for these plants, allowing thus comparisons between existing or planned industrial facilities. It also helps evaluating the foreseeable consequences of technical progress. Some results obtained are given, concerning: the investment costs sensitivity to the various technical parameters defining the fuel and their comparison according to the country or the economic area taken into account. Finally, the influence of the plants size on their investment costs is shown. (author) [French] La communication expose d'abord une methode d'analyse des couts d'investissement des usines de retraitement de l'uranium naturel irradie (inspiree de celles de LANG et de BACH, bien connues dans l'industrie petroliere) et de leurs couts d'exploitation (selon leur nature economique). Cette methode permet d'etablir des structures types de couts de ces usines et de comparer les realisations industrielles et les projets. Elle facilite l'exploration des consequences previsibles du progres technique. On indique un certain nombre de resultats obtenus, concernant la sensibilite des couts d'investissement de ces usines aux differents parametres techniques definissant le combustible et leur confrontation selon les pays ou aires economiques envisages. On montre enfin comment doit pouvoir s'exprimer l'influence de la taille des usines sur leur cout d'investissement. (auteur)

  19. In Plant Measurement and Analysis of Mixtures of Uranium and Plutonium TRU-Waste Using a {sup 252}Cf Shuffler Instrument

    Energy Technology Data Exchange (ETDEWEB)

    Hurd, J.R.

    1998-11-02

    The active-passive {sup 252}Cf shuffler instrument, installed and certified several years ago in Los Alamos National Laboratory's plutonium facility, has now been calibrated for different matrices to measure Waste Isolation Pilot Plant (WIPP)-destined transuranic (TRU)-waste. Little or no data currently exist for these types of measurements in plant environments where sudden large changes in the neutron background radiation can significantly distort the results. Measurements and analyses of twenty-two 55-gallon drums, consisting of mixtures of varying quantities of uranium and plutonium in mostly noncombustible matrices, have been recently completed at the plutonium facility. The calibration and measurement techniques, including the method used to separate out the plutonium component, will be presented and discussed. Calculations used to adjust for differences in uranium enrichment from that of the calibration standards will be shown. Methods used to determine various sources of both random and systematic error will be indicated. Particular attention will be directed to those problems identified as arising from the plant environment. The results of studies to quantify the aforementioned distortion effects in the data will be presented. Various solution scenarios will be outlined, along with those adopted here.

  20. Field test of short-notice random inspections for inventory-change verification at a low-enriched-uranium fuel-fabrication plant

    International Nuclear Information System (INIS)

    An approach of short-notice random inspections (SNRIs) for inventory-change verification can enhance the effectiveness and efficiency of international safeguards at natural or low-enriched uranium (LEU) fuel fabrication plants. According to this approach, the plant operator declares the contents of nuclear material items before knowing if an inspection will occur to verify them. Additionally, items about which declarations are newly made should remain available for verification for an agreed time. Then a statistical inference can be made from verification results for items verified during SNRIs to the entire populations, i.e. the entire strata, even if inspectors were not present when many items were received or produced. A six-month field test of the feasibility of such SNRIs took place at the Westinghouse Electric Corporation Commercial Nuclear Fuel Division during 1993. Westinghouse personnel made daily declarations about both feed and product items, uranium hexafluoride cylinders and finished fuel assemblies, using a custom-designed computer ''mailbox''. Safeguards inspectors from the IAEA conducted eight SNRIs to verify these declarations. They arrived unannounced at the plant, in most cases immediately after travel from Canada, where the IAEA maintains a regional office. Items from both strata were verified during the SNRIs by meant of nondestructive assay equipment

  1. Kvanefjeld uranium project

    International Nuclear Information System (INIS)

    The purpose of the Kvanefjeld uranium project is to evaluate the possibility of a uranium production from the deposit at Narssaq, South Greenland. The project comprises investigations in the fields of geology, mining, process chemistry and technology, economy and environment protection. The predominant uraniferous rock is a nepheline syenite called lujavrite in which the main uranium mineral is steenstrupine. The deposit can be mined in an open pit. Calculations have shown a resource of 56 million tonnes of ore with an average grade of 365 ppm corresponding to 20,400 tonnes of uranium. The uranium is extracted by a sodium carbonate solution at 260degC in an autoclave. A pilot plant has been established including ball mill, continuous pipe autoclave and a belt filter for separation of leach liquor and residue. The uranium is finally precipitated as UO2 by reduction in an autoclave at 260degC. With the existing ore sample, recoveries of more than 80% have been obtained. The carbonate leaching causes a low solubility of most contaminants in the tailings. A draft project has been prepared for an industrial plant in Greenland. The total investments have been calculated at 3 x 109 Dkr. Electrical energy is assumed to be supplied by a hydropower plant at Johan Dahl Land. The mine and mill are expected to employ 500-600 persons. (author)

  2. Performance acceptance test of a portable instrument to detect uranium in water at the DOE Advanced Waste Water Treatment Plant, Fernald, Ohio

    International Nuclear Information System (INIS)

    The Eppendorf-Biotronik Model IC 2001-2, a portable field ruggedized ion chromatography instrument, was rigorously tested at the DOE Advanced Waste Water Treatment Plant, Fernald, Ohio. This instrument rapidly detected the uranium concentration in water, and has a detection limit in the low ppb range without using the sample concentrating feature. The test set of samples analyzed included: ''Real World'' water samples from the AWWT containing uranium concentrations in the 9--110 ppb range, a sample blank, and a performance evaluation sample. The AWWT samples contained sets of both raw water and acid-preserved water samples. Selected samples were analyzed in quadruplicate to asses the instrument's precision, and these results were compared with the results from an off-site confirmatory laboratory to assess the instrument's accuracy. Additional comparisons with on-site laboratory instruments, Chemcheck KPA-11 and Scintrex UA-3 are reported. Overall, the Eppendorf-Biotronik IC 2001-2 performed exceptionally well providing a detection limit in the low ppb region (< 10 ppb) and giving rapid (< 5 minutes) accurate and reproducible analytical results for the AWWT, ''real world'', water samples with uranium concentrations in the region of interest (10--40 ppb). The per sample operating cost for this instrument is equivalent to the per sample cost for the currently used KPA. The time required to analyze a sample and provide a result is approximately the same for the CI 2001-2, KPA, and Scintrex instruments

  3. Uranium and other heavy metals in the plant-animal-human food chain near abandoned mining sites and structures in an American Indian community in northwestern New Mexico

    OpenAIRE

    Samuel-Nakamura, Christine

    2013-01-01

    The broad, long-term objective of this study is to identify the extent and impact of uranium (U) and other heavy metal (As, Cd, Cs, Pb, Mo, Se, Th, and V) contamination on harvested Ovis aries (sheep) and plants on the Dine (formerly known as Navajo) reservation. This study provides a food chain assessment of U exposure in an American Indian (AI) reservation in northwestern New Mexico. The study setting was a prime target of U mining for military purposes from 1945 to 1988. More than 1,100 ...

  4. Uranium recovery from mine water

    International Nuclear Information System (INIS)

    In many plant trials it has been proven that very small amounts (10 to 20 ppm) of uranium dissolved in mine water can be effectively recovered by the use of ion exchange resins and this uranium recovery has many advantages. In this paper an economic analysis at different levels of uranium contamination and at different market prices of uranium are described. For this study an operating mine-mill complex with a sulphuric acid leach circuit, followed by solvent extraction (SX) process, is considered, where contaminated mine water is available in excess of process requirements. It is further assumed that the sulphuric acid eluant containing uranium would be mixed with the mill pregnant liquor stream that proceeds to the SX plant for final uranium recovery

  5. Promotion of uranium enrichment business

    International Nuclear Information System (INIS)

    The Committee on Nuclear Power has studied on the basic nuclear power policy, establishing its five subcommittees, entrusted by the Ministry of Nternational Trade and Industry. The results of examination by the subcommittee on uranium enrichment business are given along with a report in this connection by the Committee. In order to establish the nuclear fuel cycle, the aspect of uranium enrichment is essential. The uranium enrichment by centrifugal process has proceeded steadily in Power Reactor and Nuclear Fuel Development Corporation. The following matters are described: the need for domestic uranium enrichment, the outlook for overseas enrichment services and the schedule for establishing domestic enrichment business, the current state of technology development, the position of the prototype enrichment plant, the course to be taken to establish enrichment business the main organization operating the prototype and commercial plants, the system of supplying centrifuges, the domestic conversion of natural uranium the subsidies for uranium enrichment business. (J.P.N.)

  6. Blueprint for domestic uranium enrichment

    International Nuclear Information System (INIS)

    The AEC advisory committee on domestic production of uranium enrichment has studied for more than a year how to achieve the domestic enrichment of uranium by the construction and operation of a commercial enriching plant using centrifugal separation method, and the report was submitted to the Atomic Energy Commission on August 18, 1980. Japan has depended wholly on overseas services for her uranium enrichment needs, but the development of domestic enrichment has been carried on in parallel. The AEC decided to construct a uranium enrichment pilot plant using centrifuges, and it has been forwarded as a national project. The plant is operated by the Power Reactor and Nuclear Fuel Development Corp. since 1979. The capacity of the plant will be raised to approximately 75 ton SWU a year. The centrifuges already operated have provided the first delivery of fuel of about 1 ton for the ATR ''Fugen''. The demand-supply balance of uranium enrichment service, the significance of the domestic enrichment of uranium, the evaluation of uranium enrichment technology, the target for domestic enrichment plan, the measures to promote domestic uranium enrichment, and the promotion of the construction of a demonstration plant are reported. (Kako, I.)

  7. Manufacture of uranium compounds for research reactors fuel elements. Participation of the UCPP (Uranium compound production plant) in the Egyptian project

    International Nuclear Information System (INIS)

    UCPP is an international qualified supplier of U3O8 with up to 20 % enrichment in U-235. The characteristics of this powder are those specified for fuel plates manufacture for test reactors. This paper describes the works performed in the plant since its beginning, emphasising those undertaken during the last years. The transference of U3O8 manufacturing technology to INVAP SE, the enterprise that installed a plant of similar characteristics in the Arabian Republic of Egypt, is especially described. (author)

  8. Evaluation of alternatives for best available technology treatment and retreatment of uranium-contaminated wastewater at the Paducah Gaseous Diffusion Plant C-400 Facility

    International Nuclear Information System (INIS)

    The Paducah Gaseous Diffusion Plant (PGDP) C-400 Decontamination Facility generates aqueous solutions that originate in drum washing, machine parts and equipment cleaning, and other decontamination processes. The chemical composition of the waste depends on the particular operation involved. In general, the waste contains uranyl, fluoride, carbonate, and nitrate ions, plus soaps, detergents, secondary contaminants, and particulate matter. The uranium content is rather variable ranging between 0.5 and 30 g/l. The main contaminants are fluoride, technetium, uranium, and other heavy metals. The plan included (1) a literature search to support best available technology (BAT) evaluation of treatment alternatives, (2) a quality assurance/quality control plan, (3) suggestion of alternative treatment options, (4) bench-scale tests studies of the proposed treatment alternatives, and (5) establishment of the final recommendation. The following report records the evaluation of items (1) to (3) of the action plan for the BAT evaluation of alternatives for the treatment and retreatment of uranium-contaminated wastewater at the PGDP C-400 treatment facility. After a thorough literature search, five major technologies were considered: (1) precipitation/coprecipitation, (2) reverse osmosis, (3) ultrafiltration, (4) supported liquid membranes, and (5) ion exchange. Biosorption was also considered, but as it is a fairly new technology with few demonstrations of its capabilities, it is mentioned only briefly in the report. Based on C-400's requirements and facilities, the precipitation/coprecipitation process appears to be the best suited for use at the plant. Four different treatment options using the precipitation/coprecipitation technology are proposed. Bench-scale studies of the four options are suggested. 37 refs

  9. Limitations on progress in developing uranium resources

    International Nuclear Information System (INIS)

    Full text: Their exists a gap between the supply of uranium to nuclear power plants and the current demand for uranium for nuclear power plants. Recently rising spot and long term uranium prices provide indication that the supply of previously mined uranium is nearing an irreducible and unavailable inventory. The gap between supply and demand is very large and the inventory of proposed new mines is quite small. There clearly is a need for new uranium production and exploration, as well as increased access to previously mined uranium inventory. The author reviews the limitations to the development of new uranium sources including limitations to access to the existing inventory. The author will discuss the major limitations to progress in finding and developing uranium resources and in the availability of previously mined uranium. The major areas discussed are: 1. Financing of new production sources and new uranium mining companies, 2. Financing of uranium exploration, 3. International Legal Barriers, 4. Political and Social Constraints on Exploration and Production. 5. Environmental and Operational Permitting of Exploration, Development and Production, 6. Motivation of Uranium Producers. 7. Experienced Personnel, 8. Limitations on Developing New Techniques and Equipment to Improve the Accessibility of Uranium Resources Economically. The author will discuss these factors in relation to each of the major uranium producing countries with specific examples from each of the major producing countries to illustrate the limitations. The author will summarize the limitations and suggest the basis for overcoming these limitations as a conclusion to this paper. (author)

  10. Kvanefjeld uranium project

    International Nuclear Information System (INIS)

    The draft uranium project ''Kvanefjeld'' describes the establishment and operation of an industrial plant for exploiting the uranium deposit at Kvanefjeld. The draft project is part of the overall pre-feasibility project and is based on its results. The draft project includes two alternative locations for the processing plant and the tailings deposit plant. The ore reserve is estimated at 56 million tons with an average content of 365 PPM. The mine will be established as an open pit, with a slope angle of 55deg. Conventional techniques are used in drilling, blasting and handling the ore. Waste rock with no uranium content will be disposed of in two ponds near the mine. The waste rock volume is estimated at 80 million tons. A processing plant for extracting uranium from the ore will be established. The technical layout of the plant is based on the extraction experiments performed at Risoe from 1981-83. Yearly capacity is 4.2 million tons of ore. Electrical energy will be supplied from a hydroelectric station to be built at Johan Dahl Land. Thermal energy (steam/heat) will be supplied from a coal-fired district heating plant to be built in connection with the processing plant. Expected power consumption is estimated at 225 GWh/year. Heat consumption is of the same order. In the third year the plant is expected to operate at full capacity. Operating costs will be Dkr. 121/ton of ore from years 1 through 7. Consumption of chemicals will be reduced from the 7th year, and operating costs will consequently drop to Dkr. 115/ton of ore. Calculations show that industrial extraction of the uranium deposit in Kvanefjeld is economically advantageous. In addition, the economy of the project is expected to improve by extracting byproducts from the ore. (EG)

  11. Uranium resource assessments

    International Nuclear Information System (INIS)

    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

  12. Valorization of small uranium deposits

    International Nuclear Information System (INIS)

    For the valorization of small uranium deposits, the Total Mining Co. has developed an original leaching process in immersed live stalls, allied to the treatment of uraniferous liquors on ion exchanger resins. This technology was put in operation at Saint-Pierre (Cantal) in 1976, at La Ribiere (Creuse) in 1982 and in Bertholene (Aveyron) in 1985. In the last mentioned installation, 75 t of uranium can be produced per year on the basis of 60 000 t of ore containing 1.5 kg of uranium per ton. The investments per kg of uranium have thus been reduced to a quarter of their value in a conventional plant

  13. The measurement of uranium in vivo while working with uranium

    International Nuclear Information System (INIS)

    The aim of the study has been to find ways of measurement in vivo while working with uranium. The estimation of radiation doses of the personnel from inhaled insoluble uranium at the fuel manufacturing plant of ASEA-ATOM is included. The installed equipment is described and the assessment of measurements is presented. The measurement of TI employees at ASEA-ATOM shows a difference to a reference group which is elucidated as the occurence of uranium in the lungs. The yearly effective dose equivalent of the uranium deposited in the lungs is estimated to approximately 1,3 mSv. No one has an uranium content exceeding 10 Bq uranium 235. (GB)

  14. Recovery of uranium from lignites

    International Nuclear Information System (INIS)

    Uranium in raw lignite is associated with the organic matter and is readily soluble in acid (and carbonate) solutions. However, beneficiation techniques were not successful for concentrating the uranium or removing part of the reagent-consuming materials. Once the lignite was heated, the uranium became much less soluble in both acid and carbonate solutions, and complete removal of carbon was required to convert it back to a soluble form. Proper burning improves acid-leaching efficiency; that is, it reduces the reagent consumption and concentrates the uranium, thereby reducing plant size for comparable uranium throughput, and it eliminates organic fouling of leach liquors. Restrictions are necessary during burning to prevent the uranium from becoming refractory. The most encouraging results were obtained by flash-burning lignite at 1200 to 13000C and utilizing the released SO2 to supplement the acid requirement. The major acid consumers were aluminum and iron

  15. Formerly utilized MED/AEC sites remedial action program: radiological survey of the former Virginia-Carolina Chemical Corporation Uranium Recovery Pilot Plant, Nichols, Florida. Final report

    International Nuclear Information System (INIS)

    The results of a radiological survey conducted at the site of a former uranium recovery pilot plant operated by the Virginia-Carolina Chemical Corporation is presented. All that remains of this operation is a concrete pad situated within the boundary of a phosphate products plant now operated by Conserv, Inc., at the Nichols, Florida site. The survey included measurements designed to characterize the residual radioactivity in the vicinity of this pilot plant and to compare the quantities with federal guidelines for the release of decontaminated property for unrestricted use. The results of this survey indicate that only small quantities of radioactivity exist above normal background levels for that area. Some soil contamination was found in the vicinity of a concrete pad on which the pilot plant stood. Much of this contamination was due to 226Ra and 238U. Some beta-gamma dose rates in excess of applicable guidelines were observed in this same area. External gamma-ray exposure rates at 1 m above the ground range from 20 to 100 μR/hr. None of the direct measurements of alpha contamination were above guideline levels

  16. Uranium comparison by means of AMS and ICP-MS and Pu and 137Cs results around an Italian Nuclear Power Plant

    Directory of Open Access Journals (Sweden)

    De Cesare M.

    2015-01-01

    Full Text Available Italy built and commissioned 4 nuclear power plants between 1958-1978, which delivered a total of 1500 MW. All four were closed down after the Chernobyl accident following a referendum in 1987. One of the plants was Garigliano, commissioned in 1959. This plant used a 160 MW BWR1 (SEU of 2.3 % and was operational from 1964 to 1979, when it was switched off for maintenance. It was definitively stopped in 1982, and is presently being decommissioned. We report here details on the chemistry procedure and on the measurements for soil samples, collected up to 4.5 km from the Nuclear Plant. A comparison between uranium (238U concentration as determined by means of AMS (Accelerator Mass Spectrometry and by ICP-MS (Inductively Coupled Plasma-Mass Spectrometry techniques respectively at the ANU (Australian National University and at the Ecowise company in Canberra, Australia, is reported, as well as 236U and 239;240Pu concentration results detected by AMS. 236U/238U and 240Pu/239Pu isotopic ratios by means of AMS are also provided. A contamination from Chernobyl is visible in the 137Cs/239+240Pu activity ratio measurements.

  17. Analysis of causes of criticality accidents at nuclear fuel processing facilities in foreign countries. Similarities to the criticality accident at JCO's uranium processing plant

    International Nuclear Information System (INIS)

    On September 30, 1999, a criticality accident occurred at the JCO's uranium processing plant, which resulted in the first nuclear accident involving a fatality, in Japan, and forced the residents in the vicinity of the site to be evacuated and be sheltered indoors. Before the JCO accident, 21 criticality accidents have been reported at nuclear fuel processing facilities in foreign countries. The present paper describes the overall trends observed in the 21 accidents and discusses the sequences and causes of the accidents analyzed in terms of similarities to the JCO accident. Almost all of them occurred with the uranium or plutonium solution and in vessels/tanks with unfavorable geometry. In some cases, the problems similar to those observed in the JCO accident were identified: violations of procedures and/or technical specifications for improving work efficiencies, procedural changes without any application to and permission from the regulatory body, lack of understanding of criticality hazards, and complacency that a criticality accident would not occur. (author)

  18. An analysis on human factor issues in criticality accident at a uranium processing plant. Pt. 2. A study on organizational factors contributing to the accident

    International Nuclear Information System (INIS)

    At 10:35 September 30th 1999, a criticality accident occurred in a uranium processing plant in Tokai-mura, Ibaraki prefecture, Japan during a job to make uranium solution. 150 people were exposed to the radiation. Two of three workers who have engaged in the job and were exposed to a massive dosage of radiation died of multi organ failures on 83 days and 210 days after the accident, respectively. The authors revealed in the former report (S99001) several latent factors contributing to pouring some 16 kg-U into the precipitation tank. It suggests some organizational factors played significant roles in this accident. Therefore, this report discusses organizational factors of this accident. As a result, this accident is heavily contributed by (1) company executives/managers' biased decision making giving emphasis on productivity or cost-effectiveness, (2) inappropriate process management, labor management and document management and (3) an organizational culture allowing them not to always follow rules. This report also proposes the directions of countermeasures to reestablish nuclear safety. (author)

  19. Czechoslovak uranium

    International Nuclear Information System (INIS)

    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

  20. Uranium mining operations in Spain

    International Nuclear Information System (INIS)

    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 U3O8 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 U3O8 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)

  1. A sequential and fast method for low level of 226Ra , 228Ra, 210Pb e 210Po in mine effluents and uranium processing plant

    International Nuclear Information System (INIS)

    Due to biological risk and long half lives, the radionuclides 228Ra, 226Ra, 210Pb and 210Po should be frequently monitored to check for any environmental contamination around mines and uranium plants. Currently, the methods used for the determination of these radionuclides take about thirty days to reach the radioactive equilibrium of the 210Pb and 226Ra daughter's. The evaluation of effluent discharges and leakage of deposits to water bodies in monitoring programs, require quick answers to implement corrective measures. Thereby fast determination methods must be implemented. This work presents a fast and sequential method to, in three days, determine accurately and sensitively, 226Ra, 228Ra, 210Pb, 210Po, in water and effluent samples

  2. Haematological malignancies in childhood in Croatia: Investigating the theories of depleted uranium, chemical plant damage and 'population mixing'

    International Nuclear Information System (INIS)

    Some of potential causes proposed to explain the reported increase of haematological malignancies in childhood during or after the war period in several countries include depleted uranium, chemical pollution and population mixing theory. The aim of this study was to define the population of Croatian children aged 0-14 years who were potentially exposed to each of those risks during the war and to investigate any possible association between the exposure and the incidence of haematological malignancies. The authors analyzed the data reported by the Cancer Registry of Croatia during the pre-war period (1986-1990), war period (1991-1995) and post-war period (1996-1999). In the group of 10 counties potentially exposed to depleted uranium and two counties where chemical war damage occurred, no significant difference in incidence of the studied haematological malignancies was noted in comparison to pre-war period. The incidence of lymphatic leukaemia significantly increased in four counties where population mixing had occurred during the war period, supporting the 'mixing theory'. In those counties, the incidence of Hodgkin's lymphoma decreased during and after the war. In Croatia as a whole, decreases in incidence of myeloid leukaemias during war and non-Hodgkin lymphoma after the war were noted

  3. Determination of Uranium and Thorium in soils and plants by ICP-MS. Case study of Buhovo region

    International Nuclear Information System (INIS)

    ICP-MS was used for determination of U and Th in soil and plant samples from Buhovo mining area. The results proved considerably higher concentrations of both elements and higher isotope ratios (238U/232Th and 235U/238U) in the investigated soils and plants in comparison to background samples. U and Th were concentrated mainly in the seeds of the plants in contrast to background plants. Highest uptake of the elements was established for the dandelion and lowest for the wheat sample

  4. The nature of contaminant uranium phases at Fernald

    International Nuclear Information System (INIS)

    Uranium-contaminated soils at the Fernald Site in Ohio have been examined using transmission electron microscopy. The uranium-bearing phases were identified as calcium uranyl phosphate (meta-autunite), uranium oxide (uraninite), uranium metaphosphate [U(PO3)4], uranium calcium oxide, uranium silicate (boltwoodite), and uranium silicide. Uranium have been deposited on the soil through chemical spills and from the operation of an incinerator plant at the site. The uranium metaphosphate phase was found predominantly at an incinerator site at Fernald. Carbonate leaching in an oxygen environment has removed some of the U(IV) phases, however [U(PO3)4] has not been removed by any of the chemical remediation technologies. The identified phases have been included in geochemical modeling of the uranium, these studies show that meta-autunite is the solubility controlling phase for uranium in Fernald soils

  5. Uranium enrichment

    International Nuclear Information System (INIS)

    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

  6. Uranium extraction in phosphoric acid

    International Nuclear Information System (INIS)

    Uranium is recovered from the phosphoric liquor produced from the concentrate obtained from phosphorus-uraniferous mineral from Itataia mines (CE, Brazil). The proposed process consists of two extraction cycles. In the first one, uranium is reduced to its tetravalent state and then extracted by dioctylpyrophosphoric acid, diluted in Kerosene. Re-extraction is carried out with concentrated phosphoric acid containing an oxidising agent to convert uranium to its hexavalent state. This extract (from the first cycle) is submitted to the second cycle where uranium is extracted with DEPA-TOPO (di-2-hexylphosphoric acid/tri-n-octyl phosphine oxide) in Kerosene. The extract is then washed and uranium is backextracted and precipitated as commercial concentrate. The organic phase is recovered. Results from discontinuous tests were satisfactory, enabling to establish operational conditions for the performance of a continuous test in a micro-pilot plant. (Author)

  7. Deradiating the former uranium capital

    International Nuclear Information System (INIS)

    The city that once proclaimed itself The Uranium Capital of America is in the process of divorcing itself from the radioactive element - literally as well as symbolically. The last vestiges of uranium are being shoveled from the community. The removal is part of the federal Department of Energy's (DOE) Remedial Action program. It was established in 1972 to clean up areas of the country in which radiation exposure in excess of normal background levels could be attributed to wastes from DOE-operated uranium processing plants. Grand Junction was the first area to qualify. A good portion of the city is built on radioactive tailings - by-products of a uranium-processing industry. The DOE and the Environmental Protection Agency established guidelines for action levels of radiation. The standards were extrapolated from data from studies of lung cancer incidence in uranium miners in Europe and the US

  8. The international traffic in uranium

    International Nuclear Information System (INIS)

    How the international traffic in uranium, contrary to the spirit of the Non-Proliferation Treaty (NPT), is being carried out by the very nations who are signatories to the NPT is described. The US did not supply enriched uranium for commissioning Koeberg nuclear power plant of South Africa, because South Africa refused to accept full scope safeguards. However, South Africa could procure necessary supplies of enriched uranium, probably from the surplus stocks of enriched uranium of European countries. In contravention of UN sanctions, many European nations are also collaborating with South Africa in illegal mining of uranium in Namibia. All these goings on indicate that the NPT's main objective is not to prevent or reduce proliferation, but to deny nuclear technology to those brown and black nations which do not sign the NPT or do not accept the full scope safeguards. (M.G.B.)

  9. Uranium hexafluoride handling

    International Nuclear Information System (INIS)

    The United States Department of Energy, Oak Ridge Field Office, and Martin Marietta Energy Systems, Inc., are co-sponsoring this Second International Conference on Uranium Hexafluoride Handling. The conference is offered as a forum for the exchange of information and concepts regarding the technical and regulatory issues and the safety aspects which relate to the handling of uranium hexafluoride. Through the papers presented here, we attempt not only to share technological advances and lessons learned, but also to demonstrate that we are concerned about the health and safety of our workers and the public, and are good stewards of the environment in which we all work and live. These proceedings are a compilation of the work of many experts in that phase of world-wide industry which comprises the nuclear fuel cycle. Their experience spans the entire range over which uranium hexafluoride is involved in the fuel cycle, from the production of UF6 from the naturally-occurring oxide to its re-conversion to oxide for reactor fuels. The papers furnish insights into the chemical, physical, and nuclear properties of uranium hexafluoride as they influence its transport, storage, and the design and operation of plant-scale facilities for production, processing, and conversion to oxide. The papers demonstrate, in an industry often cited for its excellent safety record, continuing efforts to further improve safety in all areas of handling uranium hexafluoride

  10. Uranium hexafluoride handling. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-31

    The United States Department of Energy, Oak Ridge Field Office, and Martin Marietta Energy Systems, Inc., are co-sponsoring this Second International Conference on Uranium Hexafluoride Handling. The conference is offered as a forum for the exchange of information and concepts regarding the technical and regulatory issues and the safety aspects which relate to the handling of uranium hexafluoride. Through the papers presented here, we attempt not only to share technological advances and lessons learned, but also to demonstrate that we are concerned about the health and safety of our workers and the public, and are good stewards of the environment in which we all work and live. These proceedings are a compilation of the work of many experts in that phase of world-wide industry which comprises the nuclear fuel cycle. Their experience spans the entire range over which uranium hexafluoride is involved in the fuel cycle, from the production of UF{sub 6} from the naturally-occurring oxide to its re-conversion to oxide for reactor fuels. The papers furnish insights into the chemical, physical, and nuclear properties of uranium hexafluoride as they influence its transport, storage, and the design and operation of plant-scale facilities for production, processing, and conversion to oxide. The papers demonstrate, in an industry often cited for its excellent safety record, continuing efforts to further improve safety in all areas of handling uranium hexafluoride. Selected papers were processed separately for inclusion in the Energy Science and Technology Database.

  11. Evaluation of alternatives for best available technology treatment and retreatment of uranium-contaminated solutions at the Paducah Gaseous Diffusion Plant C-400 Facility

    International Nuclear Information System (INIS)

    The Paducah Gaseous Diffusion Plant C-400 Decontamination Facility generators aqueous solutions that originate in drum washing, machine parts and equipment cleaning, and other decontamination processes. In general, the waste contains uranyl, fluoride, carbonate, and nitrate ions, in addition to soaps, detergents, secondary contaminants, and particulate matter. The main contaminants are fluoride, technetium, uranium, and other heavy metals. In accordance with Department of Energy (DOE) Order 5400.5, the releases of radioactive materials must be as low as reasonably achievable and be below the derived concentration guide limits. To comply with the DOE order, an action plan was formulated. The action plan included a literature search to support best available technology evaluation of treatment alternatives, a quality assurance/quality control plan, suggestion of alternative treatment options, bench-scale test studies of the proposed treatment alternatives, and establishment of the final recommendation. Five major technologies were considered: precipitation/coprecipitation, reverse osmosis, ultrafiltration, supported liquid membranes, and ion exchange. Biosorption was also briefly considered. Based on C-400's requirements and facilities, the precipitation/coprecipitation process appears to be the best suited for use at the plant. Four different treatment options using the precipitation/coprecipitation technology were proposed. Bench-scale studies of all four options were suggested. Options 1 and 2 represent a combination of lime-softening and iron coprecipitation. Laboratory test evaluations were initiated and the results involving Options 1 and 2 reported here. 29 refs., 1 fig., 2 tabs

  12. Uranium mining in India - past, present and future

    International Nuclear Information System (INIS)

    The mining of uranium in India in the past, present and future is discussed. Uranium Corporation of India Ltd under the administrative control of Department of Atomic Energy was formed with a specific objective of mining and milling of uranium ore in the country. Uranium recovery plants, expansion mill, bye products recovery plant were set up. Underground mining, tailing disposal, land acquisition, rehabilitation and reclaimation are discussed. Cost reduction measures in mining operations are also discussed. (N.B.)

  13. AEC determines uranium enrichment policy

    International Nuclear Information System (INIS)

    The Advisory Committee on Uranium Enrichment of the Atomic Energy Commission (AEC) has submitted a report to AEC chairman concerning the promotion of the introduction of advanced material, high performance centrifuges to replace conventional metallic drum centrifuges, and the development of next generation advanced centrifuges. The report also called for the postponement until around 1997 of the decision whether the development should be continued or not on atomic vapor laser isotope separation (AVLIS) and molecular laser isotope separation (MLIS) processes, as well as the virtual freezing of the construction of a chemical process demonstration plant. The report was approved by the AEC chairman in August. The uranium enrichment service market in the world will continue to be characterized by oversupply. The domestic situation of uranium enrichment supply-demand trend, progress of the expansion of Rokkasho enrichment plant, the trend in the development of gas centrifuge process and the basic philosophy of commercializing domestic uranium enrichment are reported. (K.I.)

  14. Review of uranium market price

    International Nuclear Information System (INIS)

    Uranium is used as an abundant source of concentrated energy and is the principal fuel for the generation of electricity by nuclear reactors. In nuclear reactors, the uranium fuel is assembled in such a way that a controlled fission chain reaction can be achieved. Since uranium is the main source of nuclear energy, demand prospects for uranium has increased dramatically with the renewed global interest in nuclear power generation in recent years. Although the global uranium market is relatively small worldwide, compared to other mineral and energy sources, it is a very important market as nuclear power generation accounts for about 18% of global electricity supply. After reaching historic lows in 1990s, uranium prices have risen substantially in recent years. The outlook for nuclear power has changed since 2000, with concerns over global warming, proven excellent safety record, competitive costs, progress on nuclear waste disposal issues and also continuing new nuclear plant construction around the world. These and various other influencing factors have resulted in the uranium market evolving from one that was driven by excess secondary supplies to that by primary production. This paper reviews the global market prices for the years 1987 until 2006 and the factors, which influence the changes in global uranium market prices. (Author)

  15. Standard specification for uranium metal enriched to more than 15 % and less Than 20 % 235U

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2000-01-01

    1.1 This specification covers nuclear grade uranium metal that has either been processed through an enrichment plant, or has been produced by the blending of highly enriched uranium with other uranium, to obtain uranium of any 235U concentration below 20 % (and greater than 15 %) and that is intended for research reactor fuel fabrication. The scope of this specification includes specifications for enriched uranium metal derived from commercial natural uranium, recovered uranium, or highly enriched uranium. Commercial natural uranium, recovered uranium and highly enriched uranium are defined in Section 3. The objectives of this specification are to define the impurity and uranium isotope limits for commercial grade enriched uranium metal. 1.2 This specification is intended to provide the nuclear industry with a standard for enriched uranium metal which is to be used in the production of research reactor fuel. In addition to this specification, the parties concerned may agree to other appropriate conditions. ...

  16. Aspects of radiological safety and protection in the decontamination of the Benefit plant of uranium in Ciudad Aldama and in the storage of its residues in Pena Blanca, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Between 1969 and 1971 the National Commission of Nuclear Energy and the Mining Fostering Commission operated coordinately a production plant of uranium and molybdenum concentrates (Benefit plant) at Ciudad Aldama, Chihuahua, Mexico. During two years of operation some 45 tonnes of uranium concentrate and approximately 35,000 tonnes of uranium wetlands were produced. These last were stored in a dam to 120 m. toward West of the plant. Due to the nearness of the population with respect to what was the Benefit plant and over all to the wetland dam, the objective of this work had two main aspects: On the one hand, to carry out the works of radiological decontamination of the benefit plant of uranium, according to the established normative by the Regulatory organization in matter of radiological safety and protection (CNSNS) for the population and the hard workers. After that the works mentioned were realized it was considered that the estate which comprises what was the Benefit plant did not reach the established criteria by the CNSNS for being considered of unrestricted use such estate and it was not allowed any type of construction in the zone which could be showed the residual contamination which remains there. On the other hand, to determine the site where could be stored the radioactive wastes generated by the radiological decontamination and the wetland mobilization for its definitive storage in benefit of the present population and of the future generations due to the radionuclides which are in a such material. The site more adequate technical and economically to storage the wastes generated by this activity was evaluated. Whereby studies about demography, use of soil and water, meteorology, hydrology and ecology were realized. The site selected being in the Pena Blanca mountains, Chihuahua, place where is located one of the uranium zones and the most important of the country. In this work, specific objectives also were treated such as: knowing the radiological

  17. Tramp uranium

    International Nuclear Information System (INIS)

    Many utilities have implemented a no leaker philosophy for fuel performance and actively pursue removing leaking fuel assemblies from their reactor cores whenever a leaking fuel assembly is detected. Therefore, the only source for fission product activity in the RCS when there are no leaking fuel assemblies is tramp uranium. A technique has been developed that strips uranium impurities from ZrCl4. Unless efforts are made to remove natural uranium impurities from reactor materials, the utilities will not be able to reduce the RCS specific 131I activity in PWRs to below the lower limit of ∼1.0 x 10-4 μCi/g

  18. Modelling the behaviour of uranium-series radionuclides in soils and plants taking into account seasonal variations in soil hydrology

    International Nuclear Information System (INIS)

    In a previous paper, a mathematical model for the behaviour of 79Se in soils and plants was described. Subsequently, a review has been published relating to the behaviour of 238U-series radionuclides in soils and plants. Here, we bring together those two strands of work to describe a new mathematical model of the behaviour of 238U-series radionuclides entering soils in solution and their uptake by plants. Initial studies with the model that are reported here demonstrate that it is a powerful tool for exploring the behaviour of this decay chain or subcomponents of it in soil-plant systems under different hydrological regimes. In particular, it permits studies of the degree to which secular equilibrium assumptions are appropriate when modelling this decay chain. Further studies will be undertaken and reported separately examining sensitivities of model results to input parameter values and also applying the model to sites contaminated with 238U-series radionuclides. - Highlights: • Kinetic model of radionuclide transport in soils and uptake by plants. • Takes soil hydrology and redox conditions into account. • Applicable to the whole U-238 chain, including Rn-222, Pb-210 and Po-210. • Demonstrates intra-season and inter-season variability on timescales up to thousands of years

  19. Experience and problems of uranium mines conservation

    International Nuclear Information System (INIS)

    In North Kazakhstan uranium province there were 12 uranium deposits which were developed during five decades by 5 ore-mining departments. Now only one of these departments randomly operates, and other ones were closed down in 1994-2000. Due to economic depression in these years the conservation works on the fulfilled its task deposits does not carrying out. Volumes of radioactive wastes in these deposits are estimated 54.5 million m3. In 2000 the 'Program of uranium mining plants conservation and uranium deposits development consequences elimination during 2000-2010' was adopted . Principal aim of the program is radioactive contamination reduction in uranium ore-mining districts to level ensuring maximal population health protection. One of the responsible enterprise for uranium mines conservation in North Kazakhstan uranium province is Republican State Enterprise 'Uranlikvidrudnik'

  20. Uranium 2011 resources, production and demand

    CERN Document Server

    Organisation for Economic Cooperation and Development. Paris

    2012-01-01

    In the wake of the Fukushima Daiichi nuclear power plant accident, questions are being raised about the future of the uranium market, including as regards the number of reactors expected to be built in the coming years, the amount of uranium required to meet forward demand, the adequacy of identified uranium resources to meet that demand and the ability of the sector to meet reactor requirements in a challenging investment climate. This 24th edition of the “Red Book”, a recognised world reference on uranium jointly prepared by the OECD Nuclear Energy Agency and the International Atomic Energy Agency, provides analyses and information from 42 producing and consuming countries in order to address these and other questions. It offers a comprehensive review of world uranium supply and demand as well as data on global uranium exploration, resources, production and reactor-related requirements. It also provides substantive new information on established uranium production centres around the world and in countri...

  1. Uranium Market

    International Nuclear Information System (INIS)

    The main fuel component for commercial nuclear power reactors is Uranium. When compared to fossil fuels, it has a competitive edge due to factors such as economics and environmental conditions and in particular due to its international market availability. Uranium world demand reached to 67 320 tU in 2004, which was covered with additional sources. To project the uranium markets behavior requires to know and to accept some conditions tied to the demand, such as the electrical world consumption, the greenhouse effect; water desalination, production of hydrogen, industrial heat, the innovative development of nuclear reactors, and the average time of 10 years between the beginning of exploration programs and definition of deposits, which it owes mainly to the difficulty of achieving the legal, environmental and local community authorizations, to open new mining centers. Uranium market future projections, made by IAEA experts in 2001, that considered middle and high demand scenarios, concluded that cumulatively to year 2050, with regard to demand it will be required 5.4 and 7.6 million tons of uranium respectively, and with regard to the uranium price, it should present a sustained increase. In the last years the situation of the uranium market has changed dramatically. In August 2006 the price of uranium reached to USD 106/kgU in the spot market, surpassing all the made projections. The increase in price that has stayed in rise in the last five years is reactivating the prospection and exploration efforts anywhere in the world, and competition between prospective areas of potential resources mainly in less explored territories

  2. The uranium market and its characteristics

    International Nuclear Information System (INIS)

    The subject is covered in sections, entitled as shown. Numerical data are indicated in parenthesis. General characteristics of the uranium market, (enrichment plant variables, fuel requirements of a 1000 MWe power plant); demand pattern (enrichment cost relationships), supply pattern; uranium price analysis, production cost (relationship between future uranium requirements and discovery rates necessary), market break-even cost (break-even uranium cost as a function of fossil fuel prices), market value (theoretical and actual supply - demand balance in uranium market, relationship between U3O8 price and world production); geographic and economic distribution of producers and consumers (world resources of uranium, relationship between U308 world production capacity and annual requirements in 1990). (U.K.)

  3. Uranium, depleted uranium, biological effects

    International Nuclear Information System (INIS)

    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)

  4. Uranium loans

    International Nuclear Information System (INIS)

    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

  5. Communication dated 19 May 2011 received from the Resident Representative of the United Kingdom of Great Britain and Northern Ireland to the Agency regarding Assurance of Supply of Enrichment Services and Low Enriched Uranium for Use in Nuclear Power Plants

    International Nuclear Information System (INIS)

    The Secretariat has received a letter dated 19 May 2011 from the Resident Representative of the United Kingdom of Great Britain and Northern Ireland to the Agency, attaching the Proposal for the Assurance of Supply of Enrichment Services and Low Enriched Uranium for Use in Nuclear Power Plants, as described in document GOV/2011/10. As requested by the Resident Representative, the letter and its attachment are circulated herewith for information of all Member States

  6. Determination of uranium in the red blood cells of the workers in the chemical processing of uranium ore

    International Nuclear Information System (INIS)

    Neutron activation analysis was used in determining uranium in the venous blood erythrocytes of controls and of workers exposed to occupational hazards in a uranium chemical treatment plant. While 4.1 +- 2.6 ppb of uranium was found in dry matter of the erythrocytes in controls, 6.5 +- 2.1 ppb of uranium was ascertained in dry matter of the erythrocytes in occupationally exposed workers of a wet preparation plant, and 37.2 +- 20.2 ppb of uranium in the erythrocytes in workers of a dry cleaning plant. (author)

  7. Behavior and Distribution of Heavy Metals Including Rare Earth Elements, Thorium, and Uranium in Sludge from Industry Water Treatment Plant and Recovery Method of Metals by Biosurfactants Application

    Directory of Open Access Journals (Sweden)

    Lidi Gao

    2012-01-01

    Full Text Available In order to investigate the behavior, distribution, and characteristics of heavy metals including rare earth elements (REEs, thorium (Th, and uranium (U in sludge, the total and fractional concentrations of these elements in sludge collected from an industry water treatment plant were determined and compared with those in natural soil. In addition, the removal/recovery process of heavy metals (Pb, Cr, and Ni from the polluted sludge was studied with biosurfactant (saponin and sophorolipid elution by batch and column experiments to evaluate the efficiency of biosurfactant for the removal of heavy metals. Consequently, the following matters have been largely clarified. (1 Heavy metallic elements in sludge have generally larger concentrations and exist as more unstable fraction than those in natural soil. (2 Nonionic saponin including carboxyl group is more efficient than sophorolipid for the removal of heavy metals in polluted sludge. Saponin has selectivity for the mobilization of heavy metals and mainly reacts with heavy metals in F3 (the fraction bound to carbonates and F5 (the fraction bound to Fe-Mn oxides. (3 The recovery efficiency of heavy metals (Pb, Ni, and Cr reached about 90–100% using a precipitation method with alkaline solution.

  8. Behavior and Distribution of Heavy Metals Including Rare Earth Elements, Thorium, and Uranium in Sludge from Industry Water Treatment Plant and Recovery Method of Metals by Biosurfactants Application

    Science.gov (United States)

    Gao, Lidi; Kano, Naoki; Sato, Yuichi; Li, Chong; Zhang, Shuang; Imaizumi, Hiroshi

    2012-01-01

    In order to investigate the behavior, distribution, and characteristics of heavy metals including rare earth elements (REEs), thorium (Th), and uranium (U) in sludge, the total and fractional concentrations of these elements in sludge collected from an industry water treatment plant were determined and compared with those in natural soil. In addition, the removal/recovery process of heavy metals (Pb, Cr, and Ni) from the polluted sludge was studied with biosurfactant (saponin and sophorolipid) elution by batch and column experiments to evaluate the efficiency of biosurfactant for the removal of heavy metals. Consequently, the following matters have been largely clarified. (1) Heavy metallic elements in sludge have generally larger concentrations and exist as more unstable fraction than those in natural soil. (2) Nonionic saponin including carboxyl group is more efficient than sophorolipid for the removal of heavy metals in polluted sludge. Saponin has selectivity for the mobilization of heavy metals and mainly reacts with heavy metals in F3 (the fraction bound to carbonates) and F5 (the fraction bound to Fe-Mn oxides). (3) The recovery efficiency of heavy metals (Pb, Ni, and Cr) reached about 90–100% using a precipitation method with alkaline solution. PMID:22693485

  9. Uranium resources and uranium supply

    International Nuclear Information System (INIS)

    The availability of natural uranium is currently considered unproblematic. Out of concern about the sufficient availability of uranium, an international working group of OECD-NEA, in which the Federal Office for Geosciences and Resources (BGR) participates as a German partner, has conducted analyses of uranium availability since 1965. Its findings are published biannually in the so-called 'Red Book', 'Uranium, Resources, Production, and Demand'. Changes in the political situation worldwide have profoundly influenced the military importance of uranium and thus also greatly improved its accessibility. As a consequence, there was a decline in production in the nineties from approx. 57,000 t of U in 1989 to, at present (2001), approx. 35,000 t annually. Estimates of the worldwide requirement of natural uranium in 2015 range between approx. 55,000 t and 80,000 t of U, because of the unforeseeable extent of the use of nuclear power, as against approx. 63,000 t of U in 2001. The most recent statistics published in the 1999 Red Bock show low-cost reserves (up to Dollar 40 per kg of U) of 1325 million t, and 2234 t of uranium at extraction costs of up to t Dollar 80 per kg. This indicates a statistical range of reserves of approx. 35 years. It should be noted that these figures are snapshots of a dynamic system. A resumption of extensive exploration and technical developments could greatly influence the resource situation. In the nineties, for instance, there is a net increase in uranium reserves of approx. 700,000 t of U as a consequence of exploration activities. (orig.)

  10. Influence of the anthropogenic changes of gamma dose radiation connected connected with uranium mining upon selected plants

    International Nuclear Information System (INIS)

    The situation of flora in the regions with expressive anthropogenic changes in the background of gamma radiation and concentration of the radon in atmospheric air was observed. The content of heavy metals in the depth of the anomaly terrain was analyzed. The analyses of the selected radionuclides in plant ash by method in thin layer were performed. The concentration of radionuclides and situation of flora was correlated. (authors)

  11. Uranium mining

    International Nuclear Information System (INIS)

    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. It 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.'

  12. 铀在植物-微生物共生体系满江红体内的分布%Distribution of Uranium in the Plant_microbe Symbiotic System_Azolla Imbircata

    Institute of Scientific and Technical Information of China (English)

    胡南; 丁德馨; 潘长春; 胡劲松; 李乐; 李广悦; 王永东; 郑济芳

    2014-01-01

    采用扫描电镜( SEM)和能谱( EDS)联用分析技术,研究了铀在植物—微生物共生体系满江红中的分布,结果发现,铀在蕨类植物满江红和微生物满江红鱼腥藻中均有分布,满江红鱼腥藻中铀含量略高于蕨类植物满江红,表明了蕨类植物满江红和微生物满江红鱼腥藻都参与了去除水体中铀的过程。%The distribution of uranium in the plant_microbe symbiotic system_Azolla imbir_cata was analyzed by scanning electron microscope( SEM) and energy dispersive spectrom_eter( EDS ) hyphenated technique. The results showed that uranium distributed in both fern_Azolla imbricata and microbe_Anabena azollae. The content of uranium in Anabena azollae was slightly higher than that in Azolla imbricata. The fern_Azolla imbricata and mi_crobe_Anabena azollae had a synergistic effect on the process of removing uranium from the water.

  13. Facilities for the concomitant recovery of valuable components created at the uranium hydrometallurgical plants and adsorption-extraction technologies of double action

    International Nuclear Information System (INIS)

    Characteristic of sorption-extraction processes for the production of associated finished products when uranium ore processing and methods for the recovery of valuable components like Mo, V, W, Re, Au, Sc, rare earths, Y, Cs, Cu, Ta, Nb, Zr, Hf, Mn, Sn, Se elaborated in the VNIIKhT are given. Particular emphasis has been placed on the experience of extraction deactivation of phosphoric acid for the purpose of uranium and thorium content lowering by the factor 20 and preparation from it ecologically pure phosphate fertilizers and food phosphates. Data on three variants for the profitable production of associated finished products: sorption and desorption of valuable components in combination with uranium and separation of extracted components on the stage of extraction refining; sorption of valuable components in combination with uranium and separation them on the stage of desorption; divided sorption separation of uranium and valuable components on selective and high concentrating ion exchangers were generalized

  14. Uranium ore leaching at Bertholene (France)

    International Nuclear Information System (INIS)

    After a brief review of the geology and mineralisation of the uranium deposit ore processing is described. It comprises an acid attack, in immersed boxes of the crushed ore (0-8 mm). Uranium is extracted from the clarified liquor by ion exchange resins, elution and fabrication of magnesium diuranate are realized in another plant

  15. Criticality accident in uranium fuel processing plant. Influence of the critical accident seen to consciousness investigation of the public

    International Nuclear Information System (INIS)

    Here was introduced a consciousness investigation result carried out at Fukui prefecture and Osaka city after about two months of the JCO criticality accident. Peoples were disturbed by the accident, and not a little changed their individual estimations on items relating to energy. However, peoples lived in Fukui prefecture did not increase rate of opposition against nuclear energy promotion and nuclear power plant construction to their living area on comparison with a year before the accident. This reason might be understood by that the accident was not an accident of a nuclear power plant directly, and that their living area was much distant from place of the accident and was not suffered any danger. On the other hand, public opinion in Osaka city made worse on comparison with that before a year, and if such worse public opinion was thought to be due to the accident, its effect could be said to be different in each area even with no direct relation to the accident to shown a result dependent upon its various conditions. As a rough tendency on psychological disturbance due to the accident, it could be said that peoples became to have feelings of avoiding hard nuclear energy technology at a chance of the accident and to direct thoughts of soft natural energy and environment respect. (G.K.)

  16. Uranium bombs

    Science.gov (United States)

    DeGroot, Gerard

    2009-11-01

    Enrico Fermi was a brilliant physicist, but he did occasionally get things wrong. In 1934 he famously bombarded a sample of uranium with neutrons. The result was astounding: the experiment had, Fermi concluded, produced element 93, later called neptunium. The German physicist Ida Noddack, however, came to an even more spectacular conclusion, namely that Fermi had split the uranium nucleus to produce lighter elements. Noddack's friend Otto Hahn judged that idea preposterous and advised her to keep quiet, since ridicule could ruin a female physicist. She ignored that advice, and was, indeed, scorned.

  17. Transfer of Plutonium-Uranium Extraction Plant and N Reactor irradiated fuel for storage at the 105-KE and 105-KW fuel storage basins, Hanford Site, Richland Washington

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE) needs to remove irradiated fuel from the Plutonium-Uranium Extraction (PUREX) Plant and N Reactor at the Hanford Site, Richland, Washington, to stabilize the facilities in preparation for decontamination and decommissioning (D ampersand D) and to reduce the cost of maintaining the facilities prior to D ampersand D. DOE is proposing to transfer approximately 3.9 metric tons (4.3 short tons) of unprocessed irradiated fuel, by rail, from the PUREX Plant in the 200 East Area and the 105 N Reactor (N Reactor) fuel storage basin in the 100 N Area, to the 105-KE and 105-KW fuel storage basins (K Basins) in the 100 K Area. The fuel would be placed in storage at the K Basins, along with fuel presently stored, and would be dispositioned in the same manner as the other existing irradiated fuel inventory stored in the K Basins. The fuel transfer to the K Basins would consolidate storage of fuels irradiated at N Reactor and the Single Pass Reactors. Approximately 2.9 metric tons (3.2 short tons) of single-pass production reactor, aluminum clad (AC) irradiated fuel in four fuel baskets have been placed into four overpack buckets and stored in the PUREX Plant canyon storage basin to await shipment. In addition, about 0.5 metric tons (0.6 short tons) of zircaloy clad (ZC) and a few AC irradiated fuel elements have been recovered from the PUREX dissolver cell floors, placed in wet fuel canisters, and stored on the canyon deck. A small quantity of ZC fuel, in the form of fuel fragments and chips, is suspected to be in the sludge at the bottom of N Reactor's fuel storage basin. As part of the required stabilization activities at N Reactor, this sludge would be removed from the basin and any identifiable pieces of fuel elements would be recovered, placed in open canisters, and stored in lead lined casks in the storage basin to await shipment. A maximum of 0.5 metric tons (0.6 short tons) of fuel pieces is expected to be recovered

  18. Uranium industry annual 1990, September 1991

    International Nuclear Information System (INIS)

    This report presents data on US uranium raw materials and uranium marketing activities of the domestic uranium industry including utilities with nuclear-powered electric generating plants. It contains aggregated data reported by US companies on the ''Uranium Industry Annual Survey'' (1990), Form EIA-858, and historical data from prior data collections and other pertinent sources. The report was prepared by the Energy Information Administration (EIA), the independent agency for data collection and analysis within the US Department of Energy. 19 figs., 47 tabs

  19. Preventing proliferation : the role of Australian uranium

    International Nuclear Information System (INIS)

    The uranium debate has polarised Australian society for almost a decade. From 1977 until just before it achieved office in 1983 the Australia Labor Party took a position of strong opposition to uranium exports. The Australian Council of Trade Unions, the Australian Democrats, the Nuclear Disarmament Party, and many other organisations and sections of the community continue to oppose uranium mining and exports. Australia's uranium is currently exported for use in the commercial nuclear fuel cycle. But as the nuclear plants which are part of this cycle spread across the world, the risk rises that they will provide the cover and facilities for increasing numbers of countries to move towards nuclear weapons capability

  20. Uranium from seawater

    International Nuclear Information System (INIS)

    A novel process for recovering uranium from seawater is proposed and some of the critical technical parameters are evaluated. The process, in summary, consists of two different options for contacting adsorbant pellets with seawater without pumping the seawater. It is expected that this will reduce the mass handling requirements, compared to pumped seawater systems, by a factor of approximately 105, which should also result in a large reduction in initial capital investment. Activated carbon, possibly in combination with a small amount of dissolved titanium hydroxide, is expected to be the preferred adsorbant material instead of the commonly assumed titanium hydroxide alone. The activated carbon, after exposure to seawater, can be stripped of uranium with an appropriate eluant (probably an acid) or can be burned for its heating value (possible in a power plant) leaving the uranium further enriched in its ash. The uranium, representing about 1% of the ash, is then a rich ore and would be recovered in a conventional manner. Experimental results have indicated that activated carbon, acting alone, is not adequately effective in adsorbing the uranium from seawater. We measured partition coefficients (concentration ratios) of approximately 103 in seawater instead of the reported values of 105. However, preliminary tests carried out in fresh water show considerable promise for an extraction system that uses a combination of dissolved titanium hydroxide (in minute amounts) which forms an insoluble compound with the uranyl ion, and the insoluble compound then being sorbed out on activated carbon. Such a system showed partition coefficients in excess of 105 in fresh water. However, the system was not tested in seawater

  1. Uranium enrichment. 1980 annual report

    International Nuclear Information System (INIS)

    This report contains data and related information on the production of enriched uranium at the gaseous diffusion plants and an update on the construction and project control center for the gas centrifuge plant. Power usage at the gaseous diffusion plants is illustrated. The report contains several glossy color pictures of the plants and processes described. In addition to gaseous diffusion and the centrifuge process, three advanced isotope separation process are now being developed. The business operation of the enrichment plants is described; charts on revenue, balance sheets, and income statements are included

  2. Uranium recovery and uranium remove from acid mine waters by ion exchange resin

    International Nuclear Information System (INIS)

    Ion exchange using resins is one of few processes capable of reducing contaminants in effluents to very low levels according to environmental legislation. In this study the process was used to remove and recovery uranium from acid mine waters at Pocos de Caldas-MG Uranium Mining and Milling Plant. The presence of pyrite in the waste rock piles, resulting acid drainage with several pollutants. Including uranium ranging from 6 to 14 mg/l, as sulfate complex, that can be removed by an anionic exchanger. Studies of uranium sorption without treatment, and with lime pretreatment of water to precipitate the iron and recovery uranium as commercial product, are presented. Uranium elution was done with NaCl solutions. Saline concentration and retention time were the parameters studied. the uranium decontaminations level in the effluents from acid mine water was 94%. (author)

  3. Riddle of depleted uranium

    International Nuclear Information System (INIS)

    Depleted Uranium (DU) is the waste product of uranium enrichment from the manufacturing of fuel rods for nuclear reactors in nuclear power plants and nuclear power ships. DU may also results from the reprocessing of spent nuclear reactor fuel. Potentially DU has both chemical and radiological toxicity with two important targets organs being the kidney and the lungs. DU is made into a metal and, due to its availability, low price, high specific weight, density and melting point as well as its pyrophoricity; it has a wide range of civilian and military applications. Due to the use of DU over the recent years, there appeared in some press on health hazards that are alleged to be due to DU. In these paper properties, applications, potential environmental and health effects of DU are briefly reviewed

  4. Uranium content in soils, vegetables, cereals and fruits

    International Nuclear Information System (INIS)

    As compared to other vegetable samples, parsley leaves showed a much higher uranium content, presumably due to tightly adhering dust which could not be removed by washing. Uranium transfer factors from the soil to the plants were calculated; these factors always include the total uranium concentration and not only the 'soluble' uranium. As compared to U-238 the activity of U-234 is nearly always higher in vegetable samples, but lower in soil samples. (orig./HP)

  5. Uranium 2009 resources, production and demand

    CERN Document Server

    Organisation for Economic Cooperation and Development. Paris

    2010-01-01

    With several countries currently building nuclear power plants and planning the construction of more to meet long-term increases in electricity demand, uranium resources, production and demand remain topics of notable interest. In response to the projected growth in demand for uranium and declining inventories, the uranium industry – the first critical link in the fuel supply chain for nuclear reactors – is boosting production and developing plans for further increases in the near future. Strong market conditions will, however, be necessary to trigger the investments required to meet projected demand. The "Red Book", jointly prepared by the OECD Nuclear Energy Agency and the International Atomic Energy Agency, is a recognised world reference on uranium. It is based on information compiled in 40 countries, including those that are major producers and consumers of uranium. This 23rd edition provides a comprehensive review of world uranium supply and demand as of 1 January 2009, as well as data on global ur...

  6. Uranium 2009: Resources, Production and Demand

    International Nuclear Information System (INIS)

    With several countries currently building nuclear power plants and planning the construction of more to meet long-term increases in electricity demand, uranium resources, production and demand remain topics of notable interest. In response to the projected growth in demand for uranium and declining inventories, the uranium industry - the first critical link in the fuel supply chain for nuclear reactors - is boosting production and developing plans for further increases in the near future. Strong market conditions will, however, be necessary to trigger the investments required to meet projected demand. The 'Red Book', jointly prepared by the OECD Nuclear Energy Agency and the International Atomic Energy Agency, is a recognised world reference on uranium. It is based on information compiled in 40 countries, including those that are major producers and consumers of uranium. This 23. edition provides a comprehensive review of world uranium supply and demand as of 1 January 2009, as well as data on global uranium exploration, resources, production and reactor-related requirements. It provides substantive new information from major uranium production centres around the world, as well as from countries developing production centres for the first time. Projections of nuclear generating capacity and reactor-related uranium requirements through 2035 are also featured, along with an analysis of long-term uranium supply and demand issues

  7. Uranium uptake of Vetiveria zizanioides (L.) Nash

    International Nuclear Information System (INIS)

    Uranium uptake of vetiver grass (Vetiveria zizanioides (L.) Nash) from Eutric Fluvisols (AK), Albic Acrisols (BG), Dystric Fluvisols (HP) and Ferralic Acrisols (TC) in northern Vietnam is assessed. The soils were mixed with aqueous solution of uranyl nitrate to make soils contaminated with uranium at 0, 50, 100, 250 mg/kg before planting the grass. The efficiency of uranium uptake by the grass was assessed based on the soil-to-plant transfer factor (TFU, kg·kg-1). It was found that the TFU values are dependent upon the soils properties. CEC facilitates the uptake and the increased soil pH could reduce the uptake and translocation of uranium in the plant. Organic matter content, as well as iron and potassium, inhibits the uranium uptake of the grass. It was revealed that the lower fertile soil, the higher uranium uptake. The translocation of uranium in root for all the soil types studied is almost higher than that in its shoot. It seems that vetiver grass could potentially be used for the purpose of phytoremediation of soils contaminated with uranium

  8. Criticality accident in uranium fuel processing plant. Emergency medical care and dose estimation for the severely overexposed patients

    Energy Technology Data Exchange (ETDEWEB)

    Akashi, Makoto; Ishigure, Nobuhito [National Inst. of Radiological Sciences, Chiba (Japan)

    2000-08-01

    A criticality accident occurred in JCO, a plant for nuclear fuel production in 1999 and three workers were exposed to extremely high-level radiation (neutron and {gamma}-ray). This report describes outlines of the clinical courses and the medical cares for the patients of this accident and the emergent medical system for radiation accident in Japan. One (A) of the three workers of JCO had vomiting and diarrhea within several minutes after the accident and another one (B) had also vomiting within one hour after. Based on these evidences, the exposure dose of A and B were estimated to be more than 8 and 4 GyEq, respectively. Generally, acute radiation syndrome (ARS) is assigned into three phases; prodromal phase, critical or manifestation phase and recovery phase or death. In the prodromal phase, anorexia, nausea, vomiting and diarrhea often develop, whereas the second phase is asymptotic. In the third phase, various syndromes including infection, hemorrhage, dehydration shock and neurotic syndromes are apt to occur. It is known that radiation exposure at 1 Gy or more might induce such acute radiation syndromes. Based on the clinical findings of Chernobyl accident, it has been thought that exposure at 0.5 Gy or more causes a lowering of lymphocyte level and a decrease in immunological activities within 48 hours. Lymphocyte count is available as an indicator for the evaluation of exposure dose in early phase, but not in later phase The three workers of JCO underwent chemical analysis of blood components, chromosomal analysis and analysis of blood {sup 24}Na immediately after the arrival at National Institute of Radiological Sciences via National Mito Hospital specified as the third and the second facility for the emergency medical care system in Japan, respectively. (M.N.)

  9. Uranium industry annual 1996

    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.

  10. Uranium industry annual 1996

    International Nuclear Information System (INIS)

    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

  11. Uranium industry annual, 1991

    International Nuclear Information System (INIS)

    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

  12. Uranium Processing Research in Australia

    International Nuclear Information System (INIS)

    Uranium processing research in Australia has included studies of flotation, magnetic separation, gravity separation, heavy medium separation, atmospheric leaching, multi-stage leaching, alkali leaching, solar heating of leach pulps, jigged-bed resin-in-pulp and solvent-in-pulp extraction. Brief details of the results obtained are given. In general, it can be said that gravity, magnetic and flotation methods are of limited usefulness in the treatment of Australian uranium ores. Alkali leaching seldom gives satisfactory recoveries and multi-stage leaching is expensive. Jigged-bed resin-in-pulp and packed tower solvent-in-pulp extraction systems both show promise, but plant-scale development work is required. Bacterial leaching may be useful in the case of certain lowgrade ores. The main difficulties to be overcome, either singly or in combination, in the case of Australian uranium ores not currently considered economically exploitable, are the extremely finely divided state of the uranium mineral, the refractory nature of the uranium mineral and adverse effects due to the gangue minerals present. With respect to known low-grade ores, it would be possible in only a few cases to achieve satisfactory recovery of uranium at reasonable cost by standard treatment methods. (author)

  13. Uranium ore processing at Lodeve

    International Nuclear Information System (INIS)

    The plant for ore treatment is described. Ore preparation, crushing, alkaline attack, by Na2CO3, washing of solid residues, treatment of uraniferous liquors and effluents are reviewed. Technical and economical information on capacity, personnel, consumptions and investments are given. 881 t of uranium were produced in 1984

  14. Uranium exploration of Samar Island

    International Nuclear Information System (INIS)

    Uranium exploration is being undertaken to meet the requirements of the Philippine Nuclear Power Plant-1 (PNPP-1) programmed to operate in 1982, for about 140 metric tons annually or 2664 MT of U3O8 up to the year 2000. Samar was chosen as the survey pilot project and the method used was a geochemical reconnaissance or low density observation survey to delineate broad areas where follow-up uranium surveys may be undertaken. Stream sediments or surface waters were collected at each sampling point at a density of one sample per 20-25 sq. km. The conductance and pH of the water were measured with a conductivity meter and pH respectively. Radioactivity was determined using a portable scintillometer. The stream sediment and heavy mineral samples were analyzed for uranium (U), copper (CCu), lead (Pb), zinc (Zn), manganese (Mn), silver (Ag), cobalt (Co), nickel (Ni). Water samples were analyzed for uranium only. The solid samples were digested in an acid mixture of 85% concentrated nitric acid and 15% concentrated hydrochloric acid, and the leachable uranium was determined using a fluorimeter. The detection limits for uranium were 0.3 ppb and 0.3 ppm for water and solid samples, respectively. Analysis for Cu, Pb, Zn, Mn, Ag, Co, and Ni were done by Atomic Absorption Spectrophotometry using the same leaching solution prepared for uranium analysis. Over 9000 determinations were done on nearly 1600 samples. The survey delineated at least two areas where follow-up surveys for uranium are warranted. These areas are the San Isidro - Catarman in Northwestern Samar, and the vicinity of Bagacay mines in Central Samar

  15. Conceptual model for water management in Brazilian semi-arid regions: From intervention to sustainability, I. Case of Lagoa Real uranium plant

    International Nuclear Information System (INIS)

    The world water lack problem has been already diagnosed and is acknowledged as one of the greatest challenges for this century. The scientific literature, documents and either nationals or internationals official reports like the Brazilian Water Agency (ANA) and UNESCO point out the main shortages and general management practices. Also in Brazil, it is a multi-facet problem that envelops several social agents for many decades and has tragic consequences in some regions of the country, like is the case of the northeastern semi-arid region. This work presents the strategies for expertise integration to attend demands for the establishment of partnerships that include several institutions, with different experiences in the region, to improve the acquaintance with dry climate in Brazilian semi-arid. The general objective was developing a conceptual model of technical multi-institutional arrangements as tools for aquifer management, promoting sustainable use of groundwater in the semi-arid region. A conceptual model is shown, based on technical, political and socio-economical dimensions of sustainability that exchange information among them and with management requirements. This process must be turned in more productive agricultural systems with the introduction of new technology that respect the family arrangement of the production units. It is also expected that validation of this conceptual model allows an applicable alternative to other areas in the future, respected of course all the geo-socio-economical constraints of each site. The newest uranium plant being operated in Brazil is located at a semi-arid region, in the municipalities of Lagoa Real and Caetite, State of Bahia, northeast region of Brazil, which shows rainfall rates of 800 mm/a. Its known resources were estimated as being of 85,000 tU at below $80/kgU cost category. The ore is mined by open pit methods and uranium is extracted by acid heap leaching. The conceptual operation plan did not include liquid

  16. Uranium recovery from seawater

    International Nuclear Information System (INIS)

    The present publication describes the development work of a process to recover uranium from seawater and the proposition of a commercial demonstration plant. The essential components of this process are verified in the laboratory scale as well as in some field tests. A detailed engineering design for a model plant in a semi-technical scale to allow field tests in the marine environment is also presented. These field tests are expected to produce more realistic data on the technical and economical feasibility of the proposed technology. Production cost estimates based on state-of-the-art technology lie around 250 Dollar/1b U3O8. However, the effect of a corresponding uranium price increase on electricity costs are comparable to cost increases in coal operated power plants caused by the desulfurisation of coal. Further reductions of the production costs in the range below 150 Dollar/1b U3O8 seem possible through special research efforts in the area of sorber development and concept design. (orig.)

  17. Uranium market

    International Nuclear Information System (INIS)

    Neuxco's estimates of uranium output from operating US centers plus facilities under construction are tabulated through 1990. Buyer inventories will continue to grow through the end of 1982 and will fall off thereafter. The relative inventory level will remain at two years or above through 1984, and will consistently drop thereafter. This is an indication of the market available for imports and for new US production. 1 table

  18. Depleted uranium

    International Nuclear Information System (INIS)

    Full text: The Director General of the International Atomic Energy Agency (IAEA), Mohamed ElBaradei, issued today the following statement: The IAEA has been involved in United Nations efforts relating to the impact of the use of depleted uranium (DU) ammunition in Kosovo. It has supported the United Nations Environment Programme (UNEP) in the assessment which it is making, at the request of the Secretary-General, of that impact. In this connection, in November 2000, Agency experts participated in a UNEP-led fact-finding mission in Kosovo. DU is only slightly radioactive, being about 40% as radioactive as natural uranium. Chemically and physically, DU behaves in the same way as natural uranium. The chemical toxicity is normally the dominant factor for human health. However, it is necessary to carefully assess the impact of DU in the special circumstances in which it was used, e.g. to determine whether it was inhaled or ingested or whether fragments came into close contact with individuals. It is therefore essential, before an authoritative conclusion can be reached, that a detailed survey of the territory in which DU was used and of the people who came in contact with the depleted uranium in any form be carried out. In the meantime it would be prudent, as recommended by the leader of the November UNEP mission, to adopt precautionary measures. Depending on the results of the survey further measures may be necessary. The Agency, within its statutory responsibilities and on the basis of internationally accepted radiation safety standards, will continue to co-operate with other organizations, in particular WHO and UNEP, with a view to carrying out a comprehensive assessment. Co-operation by and additional information from NATO will be prerequisites. The experience gained from such an assessment could be useful for similar studies that may be carried out elsewhere in the Balkans or in the Gulf. (author)

  19. Demand of natural uranium to satisfy the requirements of nuclear fuel of new nuclear power plants in Mexico; Demanda de uranio natural para satisfacer los requerimientos de combustible nuclear de nuevas centrales nucleares en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez S, J. R.; Rios, M. del C.; Alonso, G.; Palacios H, J. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: jrrs@nuclear.inin.mx

    2008-07-01

    Due to the expectation of that in Mexico new plants of nuclear energy could be installed, turns out from the interest to evaluate the uranium requirements to operate those plants and to also evaluate if the existing reserves in the country could be sufficient to satisfy that demand. Three different scenes from nuclear power plant expansion for the country are postulated here that are desirable for the diversification of generation technologies. The first scene considers a growth in the generation by nuclear means of two reactors of type ABWR that could enter operation by years 2015 and 2020, in the second considers the installation of four reactors but as of 2015 and new every 5 years, in the scene of high growth considers the installation of 6 reactors of the same type that in the other scenes, settling one every three years as of 2015. The results indicate that the uranium reserves could be sufficient to only maintain in operation to one of the reactors proposed by the time of their useful life. (Author)

  20. Deactivation of waste waters in the Czechoslovak Uranium Industry

    International Nuclear Information System (INIS)

    Deactivation techniques are described used for the treatment of waste waters from uranium mines and uranium chemical treatment plants. With treatment plant waters this is done either by precipitation of radium with barium sulfate or using multistage evaporating units. Mine waste waters are deactivated by sorption on ion exchangers; strongly basic anion exchangers, mostly Wofatit SBW, Varion AP or Ostion AU are used for uranium, while the strongly acidic Ostion KS is used for radium. (Z.M.)

  1. Uranium enrichment in France

    International Nuclear Information System (INIS)

    Eurodif's uranium enrichment plant in France will undoubtedly remain reliable, flexible and competitive for at least the next twenty years. Its replacement is nevertheless already under study and evaluation by Cogema, the main shareholder, since the investment decisions about the technology chosen for the substitution of the gaseous process diffusion will have to be made in near future. Supporting the efforts of the nuclear utilities to keep the nuclear power option viable and competitive, Cogema presently focuses on the development of laser processes, designed to attractively offer fully loaded costs, i.e. including the returns on investment, not much higher than the variable production costs of today. (orig.)

  2. Brazilian uranium exploration program

    International Nuclear Information System (INIS)

    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.)

  3. The future of uranium: Filling the gap

    International Nuclear Information System (INIS)

    Full text: The supply of uranium from new production has fallen short of nuclear power plant demand since 1985. However, this has not been a problem because uranium suppliers produced a large quantity of uranium in prior years, in anticipation of major new plant construction. When the expected new construction did not materialize, the industry was left with an over-supply of uranium. The large disparity between supply and demand hit uranium producers hard. Uranium mines closed. Some companies sold assets, stopped exploring for new sources of uranium or went out of business altogether. During this period, the shortfall between new production and reactor demand was filled by inventory and, more recently, by surplus weapons material. Surplus weapons material involves high-enriched uranium, down-blended to low-enriched uranium and limited amounts of plutonium fabricated into mixed oxide fuel. By the end of this decade, these sources of non-production uranium will be almost exhausted. Because mining exploration largely ceased in the 1990s, there most likely will not be sufficient new production on line to fill the demand. The industry faces a big question: How is the gap between new supply and demand going to be filled? The approaches include, higher burn-up fuel, greater use of mixed-oxide fuel, use of enrichment versus uranium tails assay, and mining of enrichment tailings piles. There is no one answer. The amount of supply from any one source will be dependent on the prices of uranium, enrichment and reprocessing service. The mixture of these alternatives also will be a function of the energy policy of various countries. National energy policy will impact where and how material is produced as well as how it is consumed. It will include restrictions on access to material and facilities. This paper will not address national policy. In summary, while it is expected that new production will not meet the demand for uranium, for some period of time; there are alternative

  4. Uranium in Mongolia

    International Nuclear Information System (INIS)

    Full text: Mongolian electricity is produced from fossil fuels (about 98%, mainly coal). Rapid growth in demand has given rise to power shortages, and the reliance on fossil fuels has led to much air pollution. Mongolia does not have nuclear reactor and thus is not a beneficiary of nuclear technology. In April 2008 Russia and Mongolia signed a high-level agreement to cooperate in identifying and developing Mongolia's uranium resources. Russia is also examining the feasibility of building nuclear power plants in Mongolia In our government need to create the environment for investment in nuclear power, including professional regulatory regime, policies on nuclear waste management and decommissioning, and involvement with international non-proliferation and insurance arrangements. Some 46 million kilowatt-hours of electricity are produced from one tones of natural uranium. The production of this amount of electrical power from fossil fuels would require the burning of over 20 000 tonnes of black coal or 8.5 million cubic meters of gas. Mongolia has a long history of uranium exploration commencing with joint Russian and Mongolian endeavors to 1957. Today the Canada-based Khan Resources owns a 69% share in the Dornod project through its subsidiary Central Asian Uranium Co. Ltd and Russia's Priargunsky Mining and Chemical Enterprise owns a further share. In 2007 Khan published NI 43-101 compliant indicated resource figure of 25 000 tU for the project, including probable reserves of 7 000 tU. A bankable feasibility study is now being undertaken, with capital cost estimate being US$283 million and first production in 2011. Khan has applied for a mining licence from the Mineral Resources and Petroleum Authority of Mongolia (MRPAM). (author)

  5. Uranium industry annual, 1986

    International Nuclear Information System (INIS)

    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

  6. Techno-economic influences on the long-term availability and cost of uranium

    International Nuclear Information System (INIS)

    The subject is covered in sections: the uranium resources base (list and description of uranium deposits; table of resources under type of deposit); influences (grade; uranium plant working cost distributions; costs; price; technology; scale of operation; exploration; effect of grade and throughput on production cost for a hypothetical uranium ore body; correlation between spot uranium price and exploration activity in the USA); conclusions. (U.K.)

  7. Uranium Industry Annual, 1992

    International Nuclear Information System (INIS)

    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

  8. Uranium Industry Annual, 1992

    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.

  9. Y-12 Uranium Exposure Study

    Energy Technology Data Exchange (ETDEWEB)

    Eckerman, K.F.; Kerr, G.D.

    1999-08-05

    Following the recent restart of operations at the Y-12 Plant, the Radiological Control Organization (RCO) observed that the enriched uranium exposures appeared to involve insoluble rather than soluble uranium that presumably characterized most earlier Y-12 operations. These observations necessitated changes in the bioassay program, particularly the need for routine fecal sampling. In addition, it was not reasonable to interpret the bioassay data using metabolic parameter values established during earlier Y-12 operations. Thus, the recent urinary and fecal bioassay data were interpreted using the default guidance in Publication 54 of the International Commission on Radiological Protection (ICRP); that is, inhalation of Class Y uranium with an activity median aerodynamic diameter (AMAD) of 1 {micro}m. Faced with apparently new workplace conditions, these actions were appropriate and ensured a cautionary approach to worker protection. As additional bioassay data were accumulated, it became apparent that the data were not consistent with Publication 54. Therefore, this study was undertaken to examine the situation.

  10. The manufacturing of depleted uranium biological shield components

    International Nuclear Information System (INIS)

    The unique combination of the physical and mechanical properties of uranium made it possible to manufacture biological shield components of transport package container (TPC) for transportation nuclear power plant irradiated fuel and radionuclides of radiation diagnostic instruments. Protective properties are substantially dependent on the nature radionuclide composition of uranium, that why I recommended depleted uranium after radiation chemical processing. Depleted uranium biological shield (DUBS) has improved specific mass-size characteristics compared to a shield made of lead, steel or tungsten. Technological achievements in uranium casting and machining made it possible to manufacture DUBS components of TPC up to 3 tons of mass and up to 2 metres of the maximum size. (authors)

  11. Uranium recovery from slags of metallic uranium

    International Nuclear Information System (INIS)

    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 (U3 Si2) from Hexafluoride of Uranium (UF6) with enrichment 20% in weight of 235U. 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 U3O8 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 U3O8. 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)

  12. Determination of Uranium and Plutonium Concentration in 1AF by Isotopic Dilution Mass Spectrometry Methods

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>It is important data to measure uranium and plutonium concentration for the reprocessing plant control analysis. The determination of uranium and plutonium concentration in 1AF by isotopic dilution mass

  13. 77 FR 53236 - Proposed International Isotopes Fluorine Extraction Process and Depleted Uranium Deconversion...

    Science.gov (United States)

    2012-08-31

    ... COMMISSION Proposed International Isotopes Fluorine Extraction Process and Depleted Uranium Deconversion... International Isotopes Fluorine Extraction Process and Depleted Uranium Deconversion Plant (INIS) in Lea County, New Mexico. On December 30, 2009, International Isotopes Fluorine Products, Inc. (IIFP), a...

  14. The End of Cheap Uranium

    CERN Document Server

    Dittmar, Michael

    2011-01-01

    Historic data from many countries demonstrate that on average no more than 50-70% of the uranium in a deposit could be mined. An analysis of more recent data from Canada and Australia leads to a mining model with an average deposit extraction lifetime of 10+- 2 years. This simple model provides an accurate description of the extractable amount of uranium for the recent mining operations. Using this model for all larger existing and planned uranium mines up to 2030, a global uranium mining peak of at most 58 +- 4 ktons around the year 2015 is obtained. Thereafter we predict that uranium mine production will decline to at most 54 +- 5 ktons by 2025 and, with the decline steepening, to at most 41 +- 5 ktons around 2030. This amount will not be sufficient to fuel the existing and planned nuclear power plants during the next 10-20 years. In fact, we find that it will be difficult to avoid supply shortages even under a slow 1%/year worldwide nuclear energy phase-out scenario up to 2025. We thus suggest that a world...

  15. Uranium enrichment

    International Nuclear Information System (INIS)

    This chapter discusses the development of uranium enrichment processes. In the introduction there is a brief history of uranium enrichment, followed by a summary of the criteria used for the assessment of an isotope separation process, e.g. the separation factor, separative power, and the power consumption of a separating element. This is followed by a discussion of the two main processes used, i.e. gaseous diffusion and centrifugation. The reason for the change from diffusion to centrifugation in the UK, mainly on power costs, is discussed. The development potential of centrifuges is also assessed. Other processes which have been developed up to pilot stage are described, e.g. the Becker jet nozzle and the South African process. This is followed by a description of some plasma-based methods. The next topic is concerned with chemical exchange methods and an attempt is made to assess their potential in the enrichment scene from published information. This chapter concludes with a discussion of the advanced laser isotope-separation methods. The two approaches, i.e. the atomic and the molecular routes are discussed again using published information. This information is insufficient to give a complete assessment of the methods, especially the molecular route, but is enough to give indications of their potential

  16. Chapter 1. General information about uranium. 1.10. Uranium application

    International Nuclear Information System (INIS)

    Full text: Metallic uranium or its compounds are used as nuclear fuel in nuclear reactors. A natural or low-enriched admixture of uranium isotopes is applied in stationery reactors of nuclear power plants, and products of a high enrichment degree are used in nuclear power plants or in reactors that operates with fast neutrons. 235U is a source of nuclear energy in nuclear weapons. Depleted uranium is used as armour-piercing core in bombshells. 238U serves as a source of secondary nuclear fuel - plutonium. (author)

  17. Uranium processing and properties

    CERN Document Server

    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

  18. Irradiated uranium reprocessing

    International Nuclear Information System (INIS)

    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

  19. Issues in uranium availability

    International Nuclear Information System (INIS)

    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

  20. Development of uranium industry in Romania

    International Nuclear Information System (INIS)

    The management of the uranium resources is performed in Romania by the National Uranium Company. The tasks to be done are: 1. management and protection of rare and radioactive metal ores in the exploitation areas; 2. mining, preparation, refining and trading the radioactive ores, as well as reprocessing the uranium stock from the uranium concentrate in the national reserve; 3. performing geologic and technologic studies in the exploitation areas; 4. performing studies and projects concerning the maintenance of the present facilities and unearthing new ores; 5. building industrial facilities; 6. carrying out technological transport; 7. importation-exportation operations; 8. performing micro-production activity in experimental research units; 9. personnel training; 10. medical assistance for the personnel; 11. environment protection. The company is organized as follows: 1.three branches for uranium ore mining, located at Suceava, Bihor and Banat; 2. one branch for geologic survey, located at Magurele; 3. one branch for uranium ore preparation and concentration and for refining uranium concentrates, located at Feldioara; 4. One group for mine conservation, closure and ecology, located at Bucuresti. The final product, sintered powder of UO2 produced at Feldioara plant, was tested in 1994 by the Canadian partner and met successfully the required standards. The Feldioara plant was certified as supplier of raw material for CANDU nuclear fuel production and as such, Romania is the only authorized producer of CANDU nuclear fuel in Europe and the second in the world, after Canada. Maintaining the uranium production in Romania is justified by the existence of uranium ore resources, the declining of natural gas resources, lower costs per kWh for electric nuclear power as compared to fossil-fuel power production, the possibility for Romania to become an important supplier of CANDU nuclear fuel, the low environmental impact and high costs for total shutdown of activity, high

  1. Uranium industry annual 1985

    International Nuclear Information System (INIS)

    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

  2. Department of Energy depleted uranium recycle

    International Nuclear Information System (INIS)

    With its strategic supply of depleted uranium, the Department of Energy is studying reuse of the material in nuclear radiation shields, military hardware, and commercial applications. the study is expected to warrant a more detailed uranium recycle plan which would include consideration of a demonstration program and a program implementation decision. Such a program, if implemented, would become the largest nuclear material recycle program in the history of the Department of Energy. The bulk of the current inventory of depleted uranium is stored in 14-ton cylinders in the form of solid uranium hexafluoride (UF6). The radioactive 235U content has been reduced to a concentration of 0.2% to 0.4%. Present estimates indicate there are about 55,000 UF6-filled cylinders in inventory and planned operations will provide another 2,500 cylinders of depleted uranium each year. The United States government, under the auspices of the Department of Energy, considers the depleted uranium a highly-refined strategic resource of significant value. A possible utilization of a large portion of the depleted uranium inventory is as radiation shielding for spent reactor fuels and high-level radioactive waste. To this end, the Department of Energy study to-date has included a preliminary technical review to ascertain DOE chemical forms useful for commercial products. The presentation summarized the information including preliminary cost estimates. The status of commercial uranium processing is discussed. With a shrinking market, the number of chemical conversion and fabrication plants is reduced; however, the commercial capability does exist for chemical conversion of the UF6 to the metal form and for the fabrication of uranium radiation shields and other uranium products. Department of Energy facilities no longer possess a capability for depleted uranium chemical conversion

  3. The world market-situation for uranium and its enrichment

    International Nuclear Information System (INIS)

    The development of the uranium market is described as well as all pertinent facts which may have contributed to the strong rise in uranium prices of the past three years. The policies of countries which may in the future become major uranium exporters are discussed. For the conversion of uranium there is sufficient capacity. However, if construction of new plants is not started soon shortages could occur in the early 80ies. The market for enrichment has characterized in past years by substantial overcapacities. If new enrichment plants are constructed according to present schedules this overcapacity may prevail into the early 90ies. (orig.)

  4. Treatment of mine waters discharged from underground uranium mines

    International Nuclear Information System (INIS)

    Contaminated mine water treatment before discharging into surface water streams is mandatory for the uranium mines within the National Uranium Company SA - Romania in order to limit supplementary exposure of the population living downside the mine sites. Present mine water treatment plants have to be upgraded in order to ensure the stringent limits for uranium and radium concentrations even when processing waters resulted from the mine flooding process. Ion exchange method is used for uranium removal while radium is separated by adsorption on activated carbon. Separation process and performance are presented for the water treatment plant at an active mine and at a closed mine. (author)

  5. The environmental behaviour of uranium and thorium

    International Nuclear Information System (INIS)

    Uranium and thorium have had many uses in the past, and their present and potential use as nuclear fuels in energy production is very significant. Both elements, and their daughter products, are of environmental interest because they may have effects from the time of mining to the time of ultimate disposal of used nuclear fuel. To assess the impact on the environment of man's use and disposal of uranium and thorium, we must know the physical, chemical and biological behaviour of these elements. This report summarizes the literature, updating and extending earlier reviews pertaining to uranium and thorium. The radiological properties, chemistry, forms of occurrence in nature, soil interactions, as well as distribution coefficients and mode of transport are discussed for both elements. In addition, uranium and thorium concentrations in plants, plant transfer coefficients, concentrations in soil organisms and methods of detection are summarized. (auth)

  6. Speciation of uranium in environmental relevant compartments

    International Nuclear Information System (INIS)

    In the past, the chemistry of uranium was focused on its mining and milling for production of high pure uranium compounds as initial matter of reactor fuel elements for energy production and breeding of plutonium for weapons production. In this sense, the recovery of uranium and plutonium from the used reactor fuel elements was also technical realized. The increasing input of uranium into bio-sphere by mining and milling and industrial processes like production of cement, fossil fuels, and fertilizers has led to the realization of the importance of uranium environmental chemistry. For a better assessment of radiotoxicity and transport along the food chain knowledge about the chemistry of uranium is needed in all involved compartments. Starting from uranium content in geo- and bio-systems, about the determination of chemical behavior - the speciation of uranium - is reported in selected environmental compartments like seepage waters coming from mine tailings, different kinds of bacteria living in uranium contaminated soils, and relevant forage plants growing on these soils. For uranium speciation determination direct non-invasive methods are used like various laser spectroscopic methods, and X-ray absorption spectroscopy with synchrotron radiation source, The results obtained by spectroscopic methods showed that the speciation of uranium is dominated in surface waters by uranyl-carbonate complexes in opposite to the speciation in bacteria and plants. In these compartments the speciation is dominated by binding of uranium on carboxylic and phosphorous containing functional groups. It was shown, that in the investigated systems the speciation strongly depends on different physical chemical parameters like ionic strength, kind and amount of ligands, pH, Eh e.g. In experiments with living organisms it is necessary to characterize the state of the bio-system in dependence of the used parameters to compare the obtained results (ratio of dead or living cells of bacteria

  7. Uranium 2011: Resources, Production and Demand

    International Nuclear Information System (INIS)

    In the wake of the Fukushima Daiichi nuclear power plant accident, questions are being raised about the future of the uranium market, including as regards the number of reactors expected to be built in the coming years, the amount of uranium required to meet forward demand, the adequacy of identified uranium resources to meet that demand and the ability of the sector to meet reactor requirements in a challenging investment climate. This 24. edition of the 'Red Book', a recognised world reference on uranium jointly prepared by the OECD Nuclear Energy Agency and the International Atomic Energy Agency, provides analyses and information from 42 producing and consuming countries in order to address these and other questions. It offers a comprehensive review of world uranium supply and demand as well as data on global uranium exploration, resources, production and reactor-related requirements. It also provides substantive new information on established uranium production centres around the world and in countries developing production centres for the first time. Projections of nuclear generating capacity and reactor-related requirements through 2035, incorporating policy changes following the Fukushima accident, are also featured, along with an analysis of long-term uranium supply and demand issues

  8. Documentation of the Uranium Market Model (UMM)

    International Nuclear Information System (INIS)

    The Uranium Market Model is used to make projections of activity in the US uranium mining and milling industry. The primary data sources were EIA, the Nuclear Assurance Corporation, and, to a lesser extent, Nuexco and Nuclear Resources International. The Uranium Market Model is a microeconomic simulation model in which uranium supplied by the mining and milling industry is provided to meet the demand for uranium by electric utilities with nuclear power plants. Uranium is measured on a U3O8 (uranium oxide) equivalent basis. The model considers every major production center and utility on a worldwide basis (with Centrally Planned Economies considered in a limited way), and makes annual projections for each major uranium production and consumption region in the world. Typically, nine regions are used: the United States, Canada, Australia, South Africa, Other Africa, Europe, Latin America, the Far East, and Other. Production centers and utilities are identified as being in one of these regions. In general, the model can accommodate any user-provided set of regional definitions and data

  9. Environmental design of a uranium mill

    International Nuclear Information System (INIS)

    In the frame work of the Cleaner Technology Project for Uranium Mining and Milling, Australian Nuclear and Technology Organization (ANSTO), Environment Division of ANSTO has carried out a programme of research which seeks to identify, investigate and develop cleaner technologies that have the potential to minimize the environmental impact of uranium mining and milling. This paper describes three design options of a new uranium mill that can meet environmental, technical and economical objectives. The feasibility of such an approach was examined in the laboratory and in a pilot plant study. (author)

  10. Recent activities and trends in the uranium market

    International Nuclear Information System (INIS)

    Implementing the large number of nuclear power plant projects worldwide presupposes a considerable increase in the production of natural uranium. Preparations have been made: Higher uranium prices stimulate investments into future mines and into uranium exploration. In some countries, the uranium industry is undergoing structural changes so as to be able to meet future requirements. The terms and conditions laid down in long-term uranium supply contracts (prices and fixed delivery volumes) provide present and future producers with the necessary security in investing and planning. The electricity utilities have accepted the shift from a former 'buyer's market' to a 'seller's market' and adapted their uranium supply strategies accordingly. Numerous uranium mines, most of them small, with relatively low uranium ore concentrations, are under construction or in the commissioning phase. However, as secondary sources (fuels not made up of fresh uranium) are gradually coming to an end, many more uranium deposits need to be found and developed to commercial maturity in order to ensure uranium supply also on the long term. The steadily growing industries in the front end and the back end of the fuel cycle have intensified concerns about the non-proliferation of nuclear fuels. However, political considerations with respect to proliferation resistant uranium supply strategies have met with scepticism right from the outset. (orig.)

  11. The ultimate disposition of depleted uranium

    Energy Technology Data Exchange (ETDEWEB)

    Lemons, T.R. [Uranium Enrichment Organization, Oak Ridge, TN (United States)

    1991-12-31

    Depleted uranium (DU) is produced as a by-product of the uranium enrichment process. Over 340,000 MTU of DU in the form of UF{sub 6} have been accumulated at the US government gaseous diffusion plants and the stockpile continues to grow. An overview of issues and objectives associated with the inventory management and the ultimate disposition of this material is presented.

  12. Depleted Uranium Management

    International Nuclear Information System (INIS)

    The paper considers radiological and toxic impact of the depleted uranium on the human health. Radiological influence of depleted uranium is less for 60 % than natural uranium due to the decreasing of short-lived isotopes uranium-234 and uranium-235 after enrichment. The formation of radioactive aerosols and their impact on the human are mentioned. Use of the depleted uranium weapons has also a chemical effect on intake due to possible carcinogenic influence on kidney. Uranium-236 in the substance of the depleted uranium is determined. The fact of beta-radiation formation in the uranium-238 decay is regarded. This effect practically is the same for both depleted and natural uranium. Importance of toxicity of depleted uranium, as the heavier chemical substance, has a considerable contribution to the population health. The paper analyzes risks regarding the use of the depleted uranium weapons. There is international opposition against using weapons with depleted uranium. Resolution on effects of the use of armaments and ammunitions containing depleted uranium was five times supported by the United Nations (USA, United Kingdom, France and Israel did not support). The decision for banning of depleted uranium weapons was supported by the European Parliament

  13. URANIUM DECONTAMINATION

    Science.gov (United States)

    Buckingham, J.S.; Carroll, J.L.

    1959-12-22

    A process is described for reducing the extractability of ruthenium, zirconium, and niobium values into hexone contained in an aqueous nitric acid uranium-containing solution. The solution is made acid-deficient, heated to between 55 and 70 deg C, and at that temperature a water-soluble inorganic thiosulfate is added. By this, a precipitate is formed which carries the bulk of the ruthenium, and the remainder of the ruthenium as well as the zirconium and niobium are converted to a hexone-nonextractable form. The rutheniumcontaining precipitate can either be removed from the solu tion or it can be dissolved as a hexone-non-extractable compound by the addition of sodium dichromate prior to hexone extraction.

  14. Natural uranium

    International Nuclear Information System (INIS)

    This sheet belongs to a collection which relates to the use of radionuclides essentially in unsealed sources. Its goal is to gather on a single document the most relevant information as well as the best prevention practices to be implemented. These sheets are made for the persons in charge of radiation protection: users, radioprotection-skill persons, labor physicians. Each sheet treats of: 1 - the radio-physical and biological properties; 2 - the main uses; 3 - the dosimetric parameters; 4 - the measurement; 5 - the protection means; 6 - the areas delimitation and monitoring; 7 - the personnel classification, training and monitoring; 8 - the effluents and wastes; 9 - the authorization and declaration administrative procedures; 10 - the transport; and 11 - the right conduct to adopt in case of incident or accident. This sheet deals specifically with natural uranium

  15. Arbuscular mycorrhizas contribute to phyto stabilization of uranium in uranium mining tailings

    DEFF Research Database (Denmark)

    Chen, Bao-Dong; Roos, Per; Zhu, Yong-Guan;

    2008-01-01

    Uranium (U) tailings pose environmental risks and call for proper remediation. In this paper medic and ryegrass plants were used as host plants to examine whether inoculation with an AM fungus, Glomus intraradices, would help phytostabilization of U tailings. The need of amending with uncontamina......Uranium (U) tailings pose environmental risks and call for proper remediation. In this paper medic and ryegrass plants were used as host plants to examine whether inoculation with an AM fungus, Glomus intraradices, would help phytostabilization of U tailings. The need of amending...

  16. First aid to fight hazards at the uranium ore processing plant at Seelingstaedt/Thuringia. Sofortgefahrenabwehr im Bereich der Uranerzaufbereitungsanlage Seelingstaedt/Thueringen

    Energy Technology Data Exchange (ETDEWEB)

    Gellermann, R.; Molitor, N.; Ripper, P. (Trischler und Partner GmbH, Darmstadt (Germany))

    Mining for uranium ore in Saxonia and Thuringen under the ownership of the German-Soviet group SDAG Wismut has severely affected the environment in the concerned regions over the last 45 years. By means of a special project, the article gives an overview of hazard potentials, acute hazards and envisaged first aid, as well as on additional measures to restore and revegetate the landscape. The state of knowledge on which the article is based is as at June 1991. (orig./HP).

  17. Phytoaccumulation of uranium by Phaseolus Vulgaris

    International Nuclear Information System (INIS)

    Radioactive contamination of the environment surrounding facilities where uranium has been mined and processed has occurred in many countries. If phytomanagement of uranium contaminated areas is envisaged, the impact of the contamination on the vegetation has to be investigated. Uranium is a radiotoxic and chemotoxic heavy metal. Mechanisms of toxicity have been predominantly studied on man and on some animal species. For plants, little information on uranium toxicity at the cellular level is available. In plants facing environmental stress, for example contamination by heavy metals, an increase in the formation of highly reactive oxygen species (ROS) is often observed. ROS are naturally produced in the plant cells and consequently, cells have developed several anti-oxidative defense mechanisms in order to control the redox state of the cell, an essential parameter for normal physiological and biochemical functioning. The defense system comprise antioxidative enzymes (superoxide dismutases, peroxidases, catalases, glutathione reductase) and antioxidants (e.g. glutathione, ascorbate,I). The presence of heavy metals, in particular uranium, results in an enhancement of the antioxidative defense mechanism. The objective of the study was to analyze the biological effects (biometry, stress enzyme and antioxidant content, DNA integrity) induced by bioaccumulation of uranium in the bean Phaseolus vulgaris, to evaluate whether the various investigated biomarkers are related and to define possible dose-effect relationships

  18. Uranium and the War: The effects of depleted uranium weapons in Iraq

    International Nuclear Information System (INIS)

    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.

  19. Geochemistry of natural radionuclide in soils surrounding a mining and plant uranium concentration;Geoquimica de radionuclindeos naturais em solos de areas circunvizinhas a uma unidade de mineracao e atividade de uranio

    Energy Technology Data Exchange (ETDEWEB)

    Cardoso, Gildevan Viana, E-mail: gildevan.cardoso@vta.incra.gov.b [Instituto Nacional de Colonizacao e Reforma Agraria (INCRA), Rio de Janeiro, RJ (Brazil); Amaral Sobrinho, Nelson Moura Brasil do; Mazur, Nelson, E-mail: nelmoura@ufrrj.b, E-mail: nelmazur@ufrrj.b [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil). Inst. de Agronomia. Dept. de Solos; Wasserman, Maria Angelica Vergara, E-mail: angelica@ird.gov.b [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2009-11-15

    The environmental impacts resulting from uranium exploration and processing are to a great extent identical to those caused by extractive mining activities in general. This study aimed to determine the geochemical partitioning of the natural radionuclides {sup 238}U, {sup 226}Ra and {sup 210}Pb in areas surrounding the Uranium Mining and Concentration Plant (URA) of the Brazilian Nuclear Industries S.A., in the uranium deposit region of Lagoa Real, in Caetite, southwestern Bahia state. Representative soil samples of the main regional soil classes were collected from the layer 0-20 cm, in five areas around the URA. The level of total activity and geochemical fractionation (F1 slightly acidic, F2 reducible, F3 oxidisable, F4 alkaline, and F5 residual) were determined for the five areas. The average total radioactivity levels were, in Bq kg{sup -1} soil: 50 for {sup 238}U, 51 for {sup 226}Ra, and 159 for {sup 210}Pb. During the potentially bioavailable phase (F1) 11 % were extracted for {sup 238}U, 13 % for {sup 226}Ra and 3 % for {sup 210}Pb. The bioavailability of {sup 238}U was higher in more acidic soils and the affinity for iron oxides was greater, unlike in the case of {sup 226}Ra, with the greatest bioavailability. {sup 210}Pb was predominantly associated with F5. The high percentage of {sup 238}U, {sup 226}Ra and {sup 210}Pb in the geochemical fraction F5 indicates that the concentrations observed in the five soils are predominantly associated to the parent material of these soils, rather than to an artificial contamination caused by the URA activity. (author)

  20. Morphology Characterization of Uranium Particles From Laser Ablated Uranium Materials

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    In the study, metallic uranium and uranium dioxide material were ablated by laser beam in order to simulate the process of forming the uranium particles in pyrochemical process. The morphology characteristic of uranium particles and the surface of

  1. Kvanefjeld uranium project

    International Nuclear Information System (INIS)

    This report contains a description and an investment estimate for the infrastructure connected with establishing uranium mining activities at Narssaq. The infrastructure comprises dwellings for employess, etc., personnel and cargo transport, incl. harbours, primary storage facilities and supply routes. The report does not cover the production plant, ore and tailings transport systems, energy supply, nor workshop and administration buildings. The report assumes that the Greenland mining enterprise will employ approx. 280 persons in mining and administration, and approx. 300 persons in processing plants, etc. An increased population will also provide increased demand for shops, institutions and facilities for leisure activities. It is expected that areas will be reserved for local shops, and one or two day-care institutions for children will be built. The increase in cargo transport to and from production plants and in connection with population growth will necessitate the construction of new harbours and/or extension of the existing harbour in Narssaq. The annual volumes of coal and chemical products in bulk for the processing plant will amount to approx. 160,000 t. Approx. 8,000 tons a year will be needed to satisfy the requirements of both mining and the increased population. The present volume passing through the harbour in Narssaq is approx. 7,000 t. (EG)

  2. Feasibility study of the dissolution rates of uranium ore dust, uranium concentrates and uranium compounds in simulated lung fluid

    International Nuclear Information System (INIS)

    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

  3. Balancing needs. Global trends in uranium production and demand

    International Nuclear Information System (INIS)

    In many countries, uranium is a major energy resource, fueling nuclear power plants that collectively generate about 17% of the world's electricity. With global demand for energy especially electricity projected to grow rapidly over the coming decades, the price and availability of all energy sources, including uranium, are key components in the process of energy planning and decision-making. Particularly affecting the uranium market were changing projections about nuclear power's growth and the consequent demand for nuclear fuel; the emergence of a more integrated free market system including former centrally planned economies; and the emergence into the civilian market of uranium released from dismantled nuclear weapons. All these factors contributed to uncertainties in the commercial uranium market that raised questions about future fuel supplies for nuclear power plants. Signs today indicate that the situation is changing. The world uranium market is moving towards a more balanced relationship between supply and demand

  4. Uranium management activities

    International Nuclear Information System (INIS)

    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)

  5. Uranium Provinces in China

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Three uranium provinces are recognized in China, the Southeast China uranium province, the Northeast China-lnner Mongolia uranium province and the Northwest China (Xinjiang) uranium province. The latter two promise good potential for uranium resources and are major exploration target areas in recent years. There are two major types of uranium deposits: the Phanerozoic hydrothermal type (vein type) and the Meso-Cenozoic sandstone type in different proportions in the three uranium provinces. The most important reason or prerequisite for the formation of these uranium provinces is that Precambrian uranium-enriched old basement or its broken parts (median massifs) exists or once existed in these regions, and underwent strong tectonomagmatic activation during Phanerozoic time. Uranium was mobilized from the old basement and migrated upwards to the upper structural level together with the acidic magma originating from anatexis and the primary fluids, which were then mixed with meteoric water and resulted in the formation of Phanerozoic hydrothermal uranium deposits under extensional tectonic environments. Erosion of uraniferous rocks and pre-existing uranium deposits during the Meso-Cenozoic brought about the removal of uranium into young sedimentary basins. When those basins were uplifted and slightly deformed by later tectonic activity, roll-type uranium deposits were formed as a result of redox in permeable sandstone strata.

  6. Uranium industry annual 1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-04-22

    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.

  7. Uranium industry annual 1998

    International Nuclear Information System (INIS)

    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

  8. Uranium industry annual 1994

    International Nuclear Information System (INIS)

    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

  9. Vaal Reefs: 1700 t/a uranium by 1982

    International Nuclear Information System (INIS)

    South Africa's 16th uranium plant - the South Plant of Anglo American's Vaal Reefs mine in the Western Transvaal - has been officially opened by Dr A.J.A. Roux. Vaal Reefs is South Africa's principal producer of uranium, and responsible for a quarter of the output - a proportion which will increase with the new South Plant coming fully on stream. Vaal Reefs is also the largest gold mining operation in the world

  10. Studies on uranium ore processing

    International Nuclear Information System (INIS)

    For the exploitation of domestic uranium ore deposit, comprehensive studies on uranium ore processing of the Geum-San pit ore are carried out. Physical and chemical characteristics of the Geum-San ore are similar to those of Goe-San ore and the physical beneficiation could not be applicable. Optimum operating conditions such as uranium leaching, solid-liquid separation, solvent extraction and precipitation of yellow cake are found out and the results are confirmed by the continous operation of the micro-plant with the capacity of 50Kg, ore/day. In order to improve the process of ore milling pilot plant installed recently, the feasibility of raffinate-recycle and the precipitation methods of yellow cake are intensively examined. It was suggested that the raffinate-recycle in the leaching of filtering stage could be reduced the environmental contamination and the peroxide precipitation technique was applicable to improve the purity of yellow cake. The mechanism and conditions the third phase formation are thoroughly studied and confirmed by chemical analysis of the third phase actually formed during the operation of pilot plant. The major constituents of the third phase are polyanions such as PMosub(12)Osub(40)sup(3-) or SiMosub(12)Osub(40)sup(4-). And the formation of these polyanions could be reduced by the control of redox potential and the addition of modifier. (Author)

  11. The case for enrichment of uranium in Australia

    International Nuclear Information System (INIS)

    Information is presented on the number of nuclear power plants in operation and under construction and on the extent of the use of uranium. The case for enrichment of uranium in Australia is then considered in detail and the status of feasbility studies being carried out is discussed. Arguments to support an enrichment industry include: the need for additional enrichment capacity; added value; potential profitability; increased employment and industrial opportunities; and retention of depleted uranium

  12. Uranium resources, production and fuel fabrication

    International Nuclear Information System (INIS)

    Almost all the known disseminated and vein-type uranium deposits in India are located in the Precambrian igneous and metamorphic complexes in the Peninsular Shield; the most significant reserves occur in the Singhbhum Thrust Belt of Bihar. Adequate resources of uranium to meet the country's fuel requirements for the nuclear power programme have been established. The Uranium Corporation of India has been operating commercially an underground uranium mine and a mill at Jaduguda (Bihar) since 1968. The uranium ore body is mined by the cut-and-fill method. The present mine workings, 530 m below ground level, comprise many innovative features, namely, a tower-mounted Koepe winder system, skip-loading with an underground crushing system, concrete headframe, etc. Surveillance, control and monitoring systems, especially required in the mining of low grade uranium ores, have been successfully introduced. The uranium mill adjacent to the mine uses the acid leach and ion-exchange processes of recovery. The effluents are suitably treated in a specially designed tailings pond. Other accessory economic minerals, namely chalcopyrite, molybdenite and magnetite, are profitably recovered as by-products. Fuel fabrication commenced in India with the manufacture of aluminium-clad metallic uranium fuel for the CIR reactor. Power reactor oxide fuel manufacture has been carried out initially at Trombay for the Rajasthan Power Reactor I (RAPP-I). For transferring the technology developed, industrial-scale plants have been set up in the Nuclear Fuel Complex (NFC) at Hyderabad for the manufacture of zirconium-clad natural uranium fuel for PHWRs and low enrichment uranium fuel for the BWR Tarapur Power Station

  13. From history of reception of native uranium

    International Nuclear Information System (INIS)

    Full text: Tajikistan is a mountainous country. In its recourses may found almost all chemistry elements of periodic system. Not a secret that in practical solving of problem of uranium Soviet country in 40th and after years important role play uranium resources of the Tajikistan. Academic V. Vernandskiy in his diary rouse an alarm for work state on proceeding for uranium in Soviet Union. He was entirely aware of important appeared in world, particularly, in war period in connection to open possibility of carrying out of nuclear chain reaction. He not agreed the decision to close works in Taboshar uranium mine (North Tajikistan) taking all possible actions to destroy this decision. V. Vernandskiy write that physicists 'direct all efforts for study nuclear and its theory, and here (e.g. Kapitsa, Landau) make a lot of important - but life order ore-chemical direction', which means that task of extraction of isotope of uranium-235 from uranium ore. It should mention that aim directed search of uranium ores in Tajikistan appeared in after-war years and result with openness of a number of mines, from 1926 was known Taboshar uranium mine, from ore of which, periodically was found radium. Discovery of number of uranium mines in that region did that region as with priority on organization of their industry manufacture and proceeding. With Decision of created 30 June 1941 emergency party-state body - State defense commission (SDC) from 27 November 1942 in Tajikistan was organized mining of uranium ore and its proceeding up to concentrate. Implementation of those jobs was ordered to Ministry of color metallurgy of USSR, and after two years Order of SDC from 8 December 1944 No. 7102 this industry transferred to People Secretariat on internal affairs of USSR (NKVD USSR). By order of SDC from 12 May 1945 was created in region of Leninobod-city the specialized mining plant No.6 (from 1967 Leninobod mining plant, and from 1990 State enterprise 'Vostokredmet'). On base of local

  14. Uranium: one utility's outlook

    International Nuclear Information System (INIS)

    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

  15. Uranium: a basic evaluation

    International Nuclear Information System (INIS)

    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

  16. Enriching recycled uranium

    International Nuclear Information System (INIS)

    The paper reviews the progress of the use of recycled uranium during the period 1985-8. This article was originally presented as a paper at the 1988 Uranium Institute symposium (which was held in London). A description is given of the differences between natural and recycled uranium, and the presence of U236 in recycled uranium. The concept of equivalent reactivity is described, as well as the cost benefit of using recycled uranium. A summary of Urenco tests and trials with reprocessed uranium is given. Enrichment, UF6 conversion and fuel fabrication are also discussed. (U.K.)

  17. Uranium health physics

    International Nuclear Information System (INIS)

    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

  18. Removal of uranium from uranium-contaminated soils -- Phase 1: Bench-scale testing. Uranium in Soils Integrated Demonstration

    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.

  19. Uptake of uranium by lettuce (Lactuca sativa L.) in natural uranium contaminated soils in order to assess chemical risk for consumers

    OpenAIRE

    Neves, O.; M.M. Abreu; Vicente, E.M.

    2008-01-01

    Uranium mining activity in Cunha Baixa (Portugal) village has left a legacy of polluted soils and irrigation water. A controlled field experiment was conducted with lettuce (Lactuca sativa L.) in an agricultural area nearby the abandoned mine in order to evaluate uranium uptake and distribution in roots and leaves as well as ascertain levels of uranium intake by the local inhabitants from plant consuming. Two soils with different average uranium content (38 and 106 ...

  20. El Mesquite: uranium for the future

    International Nuclear Information System (INIS)

    Mobil Oil Corporation's new Uranium Extraction Plant at El Mesquite, Texas, uses the relatively new process of in-situ leaching, which causes little environmental damage at the surface and will produce 650,000 pounds of uranium yellowcake yearly or the equivalent of 60,000 barrels of oil a day. In-situ leaching technology builds on the experience Mobil gained in waterflooding oil fields to increase production. Leaching operations will be carried out at four or five wells at a time before moving on to a new field. All land will be restored to its natural state. The uranium is separated from the leaching solution by five ion exchange units. Only four operators are needed to run the highly automated plant. Local and state cooperation were praised at the plant dedication ceremony

  1. Uranium: myths and realities the depleted uranium

    International Nuclear Information System (INIS)

    Uranium is an element whose name causes worry. The uranium properties are very unknown for people. However the element plays an important roll in the Earth as responsible of numerous natural phenomena, which are vital for life evolution. An example of the low knowledge about uranium has been the Balkan syndrome. A relation between cancers and the use of depleted uranium in ammunition in the Balkan War has been pretended to be established. From the beginning, this hypothesis could have been discarded as it has been confirmed and stated in recent reports of UNEP Commissions who have studied this matter. (Author)

  2. Uranium production

    International Nuclear Information System (INIS)

    The domestic uranium industry is in a state of stagflation. Costs continue to rise while the market for the product remains stagnant. During the last 12 months, curtailments and closures of mines and mills have eliminated over 5000 jobs in the industry, plus many more in those industries that furnish supplies and services. By January 1982, operations at four mills and the mines that furnish them ore will have been terminated. Other closures may follow, depending on cost trends, duration of current contracts, the degree to which mills have been amortized, the feasibility of placing mines on standby, the grade of the ore, and many other factors. Open-pit mines can be placed on standby without much difficulty, other than the possible cost of restoration before all the ore has been removed. There are a few small, dry, underground mines that could be mothballed; however, the major underground producers are wet sandstone mines that in most cases could not be reopened after a prolonged shutdown; mills can be mothballed for several years. Figure 8 shows the location of all the production centers in operation, as well as those that have operated or are on standby. Table 1 lists the same production centers plus those that have been deferred, showing nominal capacity of conventional mills in tons of ore per calendar day, and the industry production rate for those mills as of October 1, 1981

  3. Uranium plutonium oxide fuels

    International Nuclear Information System (INIS)

    Uranium plutonium oxide is the principal fuel material for liquid metal fast breeder reactors (LMFBR's) throughout the world. Development of this material has been a reasonably straightforward evolution from the UO2 used routinely in the light water reactor (LWR's); but, because of the lower neutron capture cross sections and much lower coolant pressures in the sodium cooled LMFBR's, the fuel is operated to much higher discharge exposures than that of a LWR. A typical LMFBR fuel assembly is shown. Depending on the required power output and the configuration of the reactor, some 70 to 400 such fuel assemblies are clustered to form the core. There is a wide variation in cross section and length of the assemblies where the increasing size reflects a chronological increase in plant size and power output as well as considerations of decreasing the net fuel cycle cost. Design and performance characteristics are described

  4. Technico-Economical study of retreated uranium reenrichment

    International Nuclear Information System (INIS)

    Spent fuel from nuclear power plants is reprocessed at La Hague reprocessing plant in France. Recovered and stored reprocessed uranium has an energy potential unutilized so far. A modelisation is proposed in this paper for evaluating the economic interest reprocessed uranium reenrichment for using it again in a power plant. After briefly recalling the fuel cycle in light water reactors and reprocessed uranium specificities, a mathematical model for multi-isotope enrichment gives a differential system governing isotopic separation. Different solutions are proposed and compared. A. de la Garza analytical model's is retained. An economic value is attributed to reprocessed uranium. Results are presented as curves for determining the sensitivity of this value to simulation parameters (natural uranium cost, enrichment required by the electricity board etc.)

  5. Uranium mining and processing: their radiation impact into the environment

    International Nuclear Information System (INIS)

    Based on Thorium and Uranium determination in soil and plants samples collected in the region of Aktau, Kazakhstan the distribution pattern of environmental pollution by these elements was correlated with the radiation dose. The main radiation source was the waste deposit of the equipment used by the uranium processing (dose higher than 5 μSv/h). The mining area and also the transportation way from mine to the uranium factory has also an radiation impact which is difficult to estimate. Based on the data found by plants and soil samples all the area under study has a higher pollution level by Thorium and Uranium than the control area (about 0.1μSv/h). Due to observed strong wind blowing in different directions it is possible that the particle of uranium ore has been transported for long distance and polluted the plants and upper soil layer. The further investigations should get more information about this supposition. (author)

  6. Uranium deposits of Ukraine for ISL mining: Developments in uranium resources of Ukraine for in situ leach (ISL) uranium mining - Historical analysis, operational, geological, environmental and economic aspects

    International Nuclear Information System (INIS)

    From 1961-1968 uranium production center of Ukraine, East Concentrating Mill and Zheltiye Vody Hydrometallurgical Plant has carried out first Ukrainian In Situ Leaching (ISL) uranium project in Devladovo of Sofiivka district (Dnipropetrovska province) and in 1964-1969 the second in Bratske of Mikolaivska province. The experiences were executed with the acid leach system. Despite its limited applicability for this time to specific types of uranium deposits called as Sandstone Uranium Deposits, the in situ leaching (ISL) method of uranium production has grown in importance for its competitive cost and has proven to be an environmentally sound technology with very little disturbance to the environment. It was also recognized that there are two distinct approaches of ISL uranium production being practiced in Eastern Europe, in particular, in Ukraine, and in the USA, later in Kazakhstan and Uzbekistan. Commercial in situ leach (ISL) uranium mining in the United States began in the mid-1970s. In 1968, for the first time in the former USSR, the East Concentration Mill and Zheltiye Vody Hydrometallurgical Plant has implemented In Situ Leach (ISL) uranium mining technology in the Devladovske uranium deposit. (author)

  7. Improvements in process technology for uranium metal production

    International Nuclear Information System (INIS)

    The research reactors in Trombay use uranium metal as a fuel. The plant to produce nuclear grade uranium metal ingots has been in operation at Trombay since 1959. Recently, the capacity of the plant has been expanded to meet the additional demand of the uranium metal. The operation of the expanded plant, has brought to the surface various shortcomings. This paper identifies various problems and describes the measures to be taken to upgrade the technology. Some comments are made on the necessity for development of technology for future requirement. (author). 6 refs., 1 fig

  8. Uranium - a factor limiting nuclear energy?

    International Nuclear Information System (INIS)

    Nuclear power has been back as a topic of public debate since early this year. A special subject under discussion is the extension of nuclear power plant life. Hardly had it been on the agenda, when interested parties announced that this st ep was impossible because uranium reserves were no longer sufficient. A variety of terms are being used in this discussion without their meaning being taken int o account: stocks, resources, and reserves. To clarify the situation, this artic le outlines important aspects of short and long term uranium supplies, and analy zes their meaning. Here are some of the most important issues under consideration: - For what period of time is there really enough uranium? - Is uranium becoming the limiting factor in the use of nuclear power? - Is uranium really a 'sustainable' energy resource? - Will higher prices extend the range? - What is the in fluence of the price of uranium on the cost of electricity generation? Among oth er results, it is found that comprehensive sources of low-price uranium and nucl ear fuels are, or can be made, available worldwide. Consequently, the 'range' is beyond the time frames currently mentioned, also as a function of technological factors, i.e. reaching several hundred years. It is also important to note that nuclear power - ensures greater independence of volatile imported sources, - guarantees reliably low electricity prices, - has a huge potential of environmental protection, and - is a clean source of energy. (orig.)

  9. Uranium, a factor limiting nuclear energy?

    International Nuclear Information System (INIS)

    Nuclear power has been back as a topic of public debate since early this year. A special subject under discussion is the extension of nuclear power plant life. Hardly had it been on the agenda, when interested parties announced that this step was impossible because uranium reserves were no longer sufficient. A variety of terms are being used in this discussion without their meaning being taken into account: stocks, resources, and reserves. To clarify the situation, this article outlines important aspects of short and long term uranium supplies, and analyzes their meaning. Here are some of the most important issues under consideration: - For what period of time is there really enough uranium? - Is uranium becoming the limiting factor in the use of nuclear power? - Is uranium really a 'sustainable' energy resource? - Will higher prices extend the range? - What is the influence of the price of uranium on the cost of electricity generation? Among other results, it is found that comprehensive sources of low-price uranium and nuclear fuels are, or can be made, available worldwide. Consequently, the 'range' is beyond the time frames currently mentioned, also as a function of technological factors, i.e. reaching several hundred years. It is also important to note that nuclear power - ensures greater independence of volatile imported sources, - guarantees reliably low electricity prices, - has a huge potential of environmental protection, and - is a clean source of energy. (orig.)

  10. Uranium 2014: Resources, Production and Demand

    International Nuclear Information System (INIS)

    Uranium is the raw material used to fuel over 400 operational nuclear reactors around the world that produce large amounts of electricity and benefit from life cycle carbon emissions as low as renewable energy sources. Although a valuable commodity, declining market prices for uranium since the Fukushima Daiichi nuclear power plant accident in 2011, driven by uncertainties concerning the future of nuclear power, have led to the postponement of mine development plans in a number of countries and raised questions about continued uranium supply. This 25. edition of the 'Red Book', a recognised world reference on uranium jointly prepared by the OECD Nuclear Energy Agency and the International Atomic Energy Agency, provides analyses and information from 45 producing and consuming countries in order to address these and other questions. It includes data on global uranium exploration, resources, production and reactor-related requirements. It offers updated information on established uranium production centres and mine development plans, as well as projections of nuclear generating capacity and reactor-related requirements through 2035, incorporating policy changes following the Fukushima accident, in order to address long-term uranium supply and demand issues. (authors)

  11. Uranium Mining and Remediation in India

    International Nuclear Information System (INIS)

    The paper describes the present situation of uranium mining and remediation in India. In India, the nuclear energy sector encompassing the complete fuel cycle is under the control of Department of Atomic Energy, Government of India. Uranium Corporation of India Ltd. (UCIL), a public sector undertaking under Department of Atomic Energy, with its headquarter at Jaduguda has been operating four underground mines, one opencast mine and two ore processing plants in East Singhbhum district of Jharkhand state. All these units are located in a geologically significant province - called Singhbhum Shear Zone, known for its uranium-copper resources. In addition, two large uranium mining and processing projects have been planned in the States of Andhra Pradesh and Meghalaya. These mines will be brought into production during the period between 2007 and 2012, and thereby increase the uranium production in the country for India's nuclear power programme. Though the mining operations for uranium in India commenced way back in the year 1968, no uranium mine has been closed so far in India. (author)

  12. Report of Sectional Committee on Industrialization of Uranium Enrichment

    International Nuclear Information System (INIS)

    In order to accelerate the development and utilization of atomic energy which is the core of the substitute energies for petroleum, it is indispensable requirement to establish independent fuel cycle as the base. In particular, the domestic production of enriched uranium is necessary to eliminate the obstacles to secure the energy supply in Japan. The construction and operation of the pilot plant for uranium enrichment by centrifugal separation method have progressed smoothly, and the technical base for the domestic production of enriched uranium is being consolidated. For the time being, the service of uranium enrichment is given by USA and France, but it is expected that the short supply will arise around 1990. The start of operation of the uranium enrichment plant in Japan is scheduled around 1990, and the scale of the plant will be expanded stepwise thereafter. The scale of production is assumed as 3000 t SWU/year in 2000. Prior to this commercial plant, the prototype plant of up to 250 t SWU/year capacity will be operated in 1986, starting the production of centrifugal separators in 1983. The production line for centrifugal separators will have the capacity of up to 125 t SWU/year. The organization for operating these plants, the home production of natural uranium conversion, the uranium enrichment by chemical method and others are described. (Kako, I.)

  13. The uranium industry of South Africa

    International Nuclear Information System (INIS)

    This paper was originally published in 1954 and is reproduced in this centenary issue of the journal of the South African Institute of Mining and Metallurgy. South Africa's economy was (and is) based on mining. The early history of the uranium mining industry (until 1954) is discussed in detail, together with its status and economy. The first quantitative assessment of the uranium potential of the Witwatersrand goldfield was made in 1945 when it was reported that South Africa had one of the largest low-grade uranium fields in the world. The first metallurgical plants brought considerable benefit to the area. The process of uranium extraction was basically similar to that employed in the recovery of gold. It could be divided into the same three main headings: agitation, filtration and precipitation. It was predicted that the program, in full swing, would possibly consume as much as 20,000 tons of manganese ore a month, as the extraction process requires dioxide. It was for this reason that manganese recovery plants have been incorporated in the process. Other materials that were to be used in large quantities were lime, limestone, animal glue and water. Considering the increasing importance of uranium in the economy of the country, the question of secrecy was becoming a problem. At that time the demand for South African uranium was guaranteed by a ten-year agreement with the British and American authorities. 3 figs

  14. Uranium exploration in Australia

    International Nuclear Information System (INIS)

    Australia has more low-cost uranium in deposits than any other country, but finding it is not easy. While the price for uranium has been low, little was found but now exploration is starting to increase.

  15. DEPLETED URANIUM TECHNICAL WORK

    Science.gov (United States)

    The Depleted Uranium Technical Work is designed to convey available information and knowledge about depleted uranium to EPA Remedial Project Managers, On-Scene Coordinators, contractors, and other Agency managers involved with the remediation of sites contaminated with this mater...

  16. Uranium mining in Australia

    International Nuclear Information System (INIS)

    The mining of uranium in Australia is criticised in relation to it's environmental impact, economics and effects on mine workers and Aborigines. A brief report is given on each of the operating and proposed uranium mines in Australia

  17. International trade in uranium

    International Nuclear Information System (INIS)

    The subject is discussed under the following headings: need for security of uranium supply; pressures on international trade; mechanism of international trade; non-proliferation and uranium trade; means of increasing security of supply. (U.K.)

  18. Brazilian uranium deposits

    International Nuclear Information System (INIS)

    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.)

  19. Uranium in Niger

    International Nuclear Information System (INIS)

    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

  20. Determination of uranium traces in nuclear cans of nuclear reactors

    International Nuclear Information System (INIS)

    To quantify the uranium content as impurity can be found in zirconium alloys and zircaloy, utilized to construct the sheaths containing fuels of the reactors of nuclear plants. The determination by fluorescence spectroscopy was employed as quality control measurement, at once the corrosion resistance, diminish with the increase of the uranium content in the alloys. (Author)