Comparative Study on Precipitation Methods of Yellow-Cake from Acid Leachate of Rock Phosphate and Its Purification
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In Situ Leach (ISL) Mining of Uranium
In Situ Leach (ISL) Mining of Uranium (June 2009) l Most uranium mining in the USA and Kazakhstan is now by in situ leach methods, also known as in situ recovery (ISR). l In USA ISL is seen as the most cost effective and environmentally acceptable method of mining, and Australian experience supports this. l Australia's first ISL uranium mine is Beverley, which started operation late in 2000. The proposal for Honeymoon has government approval and it is expected to be operating in 2008. Conventional mining involves removing mineralised rock (ore) from the ground, breaking it up and treating it to remove the minerals being sought. In situ leaching (ISL), also known as solution mining, or in situ recovery (ISR) in North America, involves leaving the ore where it is in the ground, and recovering the minerals from it by dissolving them and pumping the pregnant solution to the surface where the minerals can be recovered. Consequently there is little surface disturbance and no tailings or waste rock generated. However, the orebody needs to be permeable to the liquids used, and located so that they do not contaminate ground water away from the orebody. Uranium ISL uses the native groundwater in the orebody which is fortified with a complexing agent and in most cases an oxidant. It is then pumped through the underground orebody to recover the minerals in it by leaching. Once the pregnant solution is returned to the surface, the uranium is recovered in much the same way as in any other uranium plant (mill). In Australian ISL mines (Beverley and the soon to be opened Honeymoon Mine) the oxidant used is hydrogen peroxide and the complexing agent sulfuric acid. -
FACT SHEET Office of Public Affairs
FACT SHEET Office of Public Affairs Phone: 301-415-8200 Email: [email protected] Uranium Recovery Background The production of fuel for nuclear power plants starts with taking uranium ore from the ground and then purifying and processing it through a series of steps. Uranium recovery focuses on extracting natural uranium ore from the earth and concentrating (or milling) that ore. These recovery operations produce a product, called "yellowcake," which is then transported to a succession of fuel cycle facilities where the yellowcake is transformed into fuel for nuclear power reactors. In addition to yellowcake, uranium recovery operations generate waste products, called byproduct materials, that contain low levels of radioactivity. The NRC does not regulate uranium mining or mining exploration, but does have authority over milling of mined materials and in situ processes used to recover uranium, as well as mill tailings. Today’s conventional uranium mills and in situ recovery (ISR) facilities are operating safely and in a manner that is protective of the environment. The NRC regulates these facilities in close coordination with other Federal agencies and State and Tribal governments and provides technical support and guidance to those Agreement States that have authority over uranium recovery activities. Discussion The NRC becomes involved in uranium recovery operations when the ore is processed and physically or chemically altered. This happens either in a conventional, heap leach uranium mill, or ISR. For that reason, the NRC regulates ISR facilities as well as uranium mills and the disposal of liquid and solid wastes from uranium recovery operations (including mill tailings). -
Gas Phase Chemical Evolution of Uranium, Aluminum, and Iron Oxides Received: 22 January 2018 Batikan Koroglu1, Scott Wagnon 1, Zurong Dai1, Jonathan C
www.nature.com/scientificreports OPEN Gas Phase Chemical Evolution of Uranium, Aluminum, and Iron Oxides Received: 22 January 2018 Batikan Koroglu1, Scott Wagnon 1, Zurong Dai1, Jonathan C. Crowhurst1, Accepted: 19 June 2018 Michael R. Armstrong1, David Weisz1, Marco Mehl1,2, Joseph M. Zaug1, Harry B. Radousky1 & Published: xx xx xxxx Timothy P. Rose1 We use a recently developed plasma-fow reactor to experimentally investigate the formation of oxide nanoparticles from gas phase metal atoms during oxidation, homogeneous nucleation, condensation, and agglomeration processes. Gas phase uranium, aluminum, and iron atoms were cooled from 5000 K to 1000 K over short-time scales (∆t < 30 ms) at atmospheric pressures in the presence of excess oxygen. In-situ emission spectroscopy is used to measure the variation in monoxide/atomic emission intensity ratios as a function of temperature and oxygen fugacity. Condensed oxide nanoparticles are collected inside the reactor for ex-situ analyses using scanning and transmission electron microscopy (SEM, TEM) to determine their structural compositions and sizes. A chemical kinetics model is also developed to describe the gas phase reactions of iron and aluminum metals. The resulting sizes and forms of the crystalline nanoparticles (FeO-wustite, eta-Al2O3, UO2, and alpha-UO3) depend on the thermodynamic properties, kinetically-limited gas phase chemical reactions, and local redox conditions. This work shows the nucleation and growth of metal oxide particles in rapidly-cooling gas is closely coupled to the kinetically-controlled chemical pathways for vapor-phase oxide formation. Gas phase nucleation and growth of metal oxide nanoparticles is an important topic for many areas of chemistry, physics, material science, and engineering1–6. -
Implementing Safeguards-By-Design at Natural Uranium Conversion Plants
NIS Office of Nuclear Safeguards and Security Safeguards-By-Design Facility Guidance Series (NGSI-SBD-002) August 2012 Implementing Safeguards-by-design at Natural Uranium Conversion Plants U.S. DEPARTMENT OF ENERG National Nuclear Security AdministrationY IMPLEMENTING SAFEGUARDS-BY-DESIGN AT NATURAL URANIUM CONVERSION PLANTS Lisa Loden John Begovich Date Published: July 2012 iii CONTENTS Page CONTENTS ......................................................................................................................................... IV 1. INTRODUCTION AND PURPOSE ................................................................................................. 1 2. KEY DEFINITIONS ......................................................................................................................... 2 3. SAFEGUARDS AT NUCPS ............................................................................................................. 7 3.1 SAFEGUARDS OBJECTIVES ................................................................................................. 7 3.2 TRADITIONAL AND INTEGRATED SAFEGUARDS ......................................................... 7 3.3 SAFEGUARDS RESPONSIBILITIES ..................................................................................... 8 3.3.1 STATE REGULATORY AUTHORITY RESPONSIBILITIES ..................................... 8 3.3.2 IAEA RESPONSIBILITIES ............................................................................................ 9 4. ELEMENTS OF FACILITY DESIGN THAT ARE RELEVANT -
Molecular Characterization of Uranium(VI) Sorption Complexes on Iron(III)-Rich Acid Mine Water Colloids
Geochimica et Cosmochimica Acta 70 (2006) 5469–5487 www.elsevier.com/locate/gca Molecular characterization of uranium(VI) sorption complexes on iron(III)-rich acid mine water colloids Kai-Uwe Ulrich a,*, Andre´ Rossberg a,b, Harald Foerstendorf a, Harald Za¨nker a, Andreas C. Scheinost a,b a Institute of Radiochemistry, FZ Rossendorf e.V., P.O. Box 510119, D-01314 Dresden, Germany b Rossendorf Beamline at ESRF, B.P. 220, F-38043 Grenoble, France Received 7 November 2005; accepted in revised form 21 August 2006 Abstract A mixing of metal-loaded acid mine drainage with shallow groundwater or surface waters usually initiates oxidation and/or hydrolysis of dissolved metals such as iron (Fe) and aluminum (Al). Colloidal particles may appear and agglomerate with increasing pH. Likewise chemical conditions may occur while flooding abandoned uranium mines. Here, the risk assessment of hazards requires reliable knowl- edge on the mobility of uranium (U). A flooding process was simulated at mesocosm scale by mixing U-contaminated acid mine water with near-neutral groundwater under oxic conditions. The mechanism of U-uptake by fresh precipitates and the molecular structure of U bonding were determined to estimate the mobility of U(VI). Analytical and spectroscopic methods such as Extended X-ray Absorption Fine-Structure (EXAFS) spectroscopy at the Fe K-edge and the U LIII-edge, and Attenuated Total Reflectance Fourier Transform Infra- red (ATR-FTIR) spectroscopy were employed. The freshly formed precipitate was identified as colloidal two-line ferrihydrite. It removed U(VI) from solution by sorption processes, while surface precipitation or structural incorporation of U was not observed. -
Depleted Uranium Technical Brief
Disclaimer - For assistance accessing this document or additional information,please contact [email protected]. Depleted Uranium Technical Brief United States Office of Air and Radiation EPA-402-R-06-011 Environmental Protection Agency Washington, DC 20460 December 2006 Depleted Uranium Technical Brief EPA 402-R-06-011 December 2006 Project Officer Brian Littleton U.S. Environmental Protection Agency Office of Radiation and Indoor Air Radiation Protection Division ii iii FOREWARD The Depleted Uranium Technical Brief 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 material. It addresses relative questions regarding the chemical and radiological health concerns involved with depleted uranium in the environment. This technical brief was developed to address the common misconception that depleted uranium represents only a radiological health hazard. It provides accepted data and references to additional sources for both the radiological and chemical characteristics, health risk as well as references for both the monitoring and measurement and applicable treatment techniques for depleted uranium. Please Note: This document has been changed from the original publication dated December 2006. This version corrects references in Appendix 1 that improperly identified the content of Appendix 3 and Appendix 4. The document also clarifies the content of Appendix 4. iv Acknowledgments This technical bulletin is based, in part, on an engineering bulletin that was prepared by the U.S. Environmental Protection Agency, Office of Radiation and Indoor Air (ORIA), with the assistance of Trinity Engineering Associates, Inc. -
Final Report
BNL-52661 Formal Report MECHANISMS OF RADIONUCLIDE-HYROXYCARBOXYLIC ACID INTERACTIONS FOR DECONTAMINATION OF METALLIC SURFACES A.J. FRANCIS, C.J. DODGE, AND J.B. GILLOW Brookhaven National Laboratory, Upton, NY 11973 G.P. HALADA AND C.R. CLAYTON Department of Materials Science, SUNY at Stony Brook, NY 11794 FINAL REPORT PROJECT PERIOD: 10/1/98 TO 9/30/01 PROJECT NUMBER: 64946 DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United State Government nor any agency thereof, nor any of their employees, not any of their contractors, subcontractors, or their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency, contractor, or subcontractor thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency, contractor or subcontractor thereof. MECHANISMS OF RADIONUCLIDE-HYROXYCARBOXYLIC ACID INTERACTIONS FOR DECONTAMINATION OF METALLIC SURFACES* A.J. FRANCIS, C.J. DODGE, AND J.B. GILLOW Brookhaven National Laboratory, Upton, NY 11973 G.P. HALADA AND C.R. CLAYTON Department of Materials Science, SUNY at Stony Brook, NY 11794 FINAL REPORT PROJECT PERIOD: 10/1/98 TO 9/30/01 PROJECT NUMBER: 64946 *This work was performed under the auspices of the U.S. -
Two Paths to a Nuclear Bomb Iran Has Historically Pursued Work on Both Uranium- and Plutonium-Weapons Programs, Western O Cials Say
Two Paths to a Nuclear Bomb Iran has historically pursued work on both uranium- and plutonium-weapons programs, Western ocials say. The 2015 nuclear deal set temporary limits on a wide range of Iran's nuclear work and committed Tehran to never work on nuclear weapons. Here's how far down those paths Iran is. Creating weapons-grade nuclear fuel Uranium 1 Low-grade uranium ore is 2 Centrifuges are set up in 3 Enriching uranium to 5% is the 4 It takes roughly 200 kg to 250 kg of 20% mined and chemically treated cascades to enrich the uranium. most time-consuming part of enriched uranium to produce the 25 kg of to produce a concentrated The sophisticated process can producing weapons-grade material. 90% enriched uranium, the amount needed yellowcake. After a conversion take years to establish. Iran Iran on Monday exceeded its for a bomb. Iran has reached 20% purity in process, it is fed into produced around 20,000 basic permitted 300-kg stockpile of the past but has never enriched above that centrifuges. centrifuges but is doing research uranium enriched to 3.67%. level. The enriched uranium is converted to Weaponizing nuclear fuel on more advanced machines. uranium metal for weapon use. Deploying the nuclear fuel in a Centrifuges weapon presents technical challenges, many of which Iran isn’t believed to have mastered. Detonating the 5% enriched Uranium Yellowcake Uranium 20% weapon requires a fission ore hexaflouride uranium 90% reaction. The nuclear payload 25kg must be attached to a missile, and the payload must be able 200-250 kg to withstand reentry through through earth's atmosphere as Plutonium it descends to its target. -
Precipitation of Aluminum Containing Species in Tank Wastes
PNNL-13881 Precipitation of Aluminum Containing Species in Tank Wastes S.V. Mattigod K.E. Parker D.T. Hobbs D.E. McCready April 2002 Prepared for the U.S. Department of Energy under Contract DE-AC06-76RL01830 PNNL-13881 DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor Battelle Memorial Institute, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof, or Battelle Memorial Institute. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. PACIFIC NORTHWEST NATIONAL LABORATORY operated by BATTELLE for the UNITED STATES DEPARTMENT OF ENERGY under Contract DE-AC06-76RL01830 This document was printed on recycled paper. (8/00 PNNL-13881 Precipitation of Aluminum Containing Species in Tank Wastes S. V. Mattigod D. T. Hobbs K. E. Parker D. E. McCready April 2002 Prepared for the U.S. Department of Energy under Contract DE-AC06-76RL01830 Pacific Northwest National Laboratory Richland, Washington 99352 Summary Aluminisilicate deposit buildup experienced during the tank waste volume-reduction process at the Savannah River Site (SRS) required an evaporator to be shut down in October 1999. -
Comparative Study on Precipitation Methods of Yellow
Precipitation and purification of uranium from rock phosphate Elshafeea H. Y. Abow Slama1, Etemad Ebraheem2 and Adam K. Sam1 1Sudan Atomic Energy Commission P.O. Box 3001, Khartoum-Sudan 2 Sinner University ABSTRACT This study was carried-out to leach uranium from rock phosphate using sulphuric acid in the presence of potassium chlorate as an oxidant and to investigate the relative purity of different forms of yellow cakes produced with ammonia {( NH 4 )2 U2O7 }, magnesia (UO3.xH 2O ) and sodium hydroxide Na2U 2O7 as precipitants, as well as purification of the products with TBP extraction and matching its impurity levels with specifications of the commercial products. Alpha-particle spectrometry was used for determination of activity concentration of uranium isotopes (234U and 238U) in rock phosphate, resulting green phosphoric acid solution, and in different forms of the yellow cake from which the equivalent mass concentration of uranium was deduced. Likewise, atomic absorption spectroscopy (AAS) was used for determination of impurities (Pb, Ni, Cd, Fe, Zn, Mn, and Cu). On the average, the equivalent mass concentration of uranium was 119.38±79.66 ppm (rock phosphate) and 57.85±20.46 ppm (green solution) with corresponding low percent of dissolution (48%) which is considered low. The isotopic ratio (234U: 238U) in all stages of hydrometallurgical process was not much differ from unity indicating lack of fractionation. Upon comparing the levels of impurities in different form of crude yellow cakes, it was found that the lowest levels were measured in UO3.xH2O. This implies that saturated magnesia is least aggressive relative to other precipitants and gives relatively pure crude cake. -
Uranium, Cesium, and Mercury Leaching and Recovery from Cemented Radioactive Wastes in Sulfuric Acid and Iodide Media
Article Uranium, Cesium, and Mercury Leaching and Recovery from Cemented Radioactive Wastes in Sulfuric Acid and Iodide Media Nicolas Reynier 1,*, Rolando Lastra 1, Cheryl Laviolette 1, Jean-François Fiset 1, Nabil Bouzoubaâ 1 and Mark Chapman 2 Received: 28 September 2015 ; Accepted: 10 November 2015 ; Published: 20 November 2015 Academic Editor: Mostafa Fayek 1 CanmetMINING, Natural Resources Canada, 3484 Limebank Rd., Ottawa, ON K1A 0E4, Canada; [email protected] (R.L.); [email protected] (C.L.); jean-francois.fi[email protected] (J.-F.F.); [email protected] (N.B.) 2 Canadian Nuclear Laboratories, Chalk River Laboratories, Plant Road, Chalk River, ON K0J 1 J0, Canada; [email protected] * Correspondence: [email protected]; Tel.: +1-613-954-5602; Fax: +1-613-954-6929 Abstract: The Canadian Nuclear Laboratories (CNL) is developing a long-term management strategy for its existing inventory of solid radioactive cemented wastes, which contain uranium, mercury, fission products, and a number of minor elements. The composition of the cemented radioactive waste poses significant impediments to the extraction and recovery of uranium using conventional technology. The goal of this research was to develop an innovative method for uranium, mercury and cesium recovery from surrogate radioactive cemented waste (SRCW). Leaching using sulfuric acid and saline media significantly improves the solubilization of the key elements from the SRCW. Increasing the NaCl concentration from 0.5 to 4 M increases the mercury solubilization from 82% to 96%. The sodium chloride forms a soluble mercury complex when mercury is present as HgO or metallic mercury but not with HgS that is found in 60 ˝C cured SRCW. -
Uranium for Nuclear Power: an Introduction 1
Stichting Laka: Documentatie- en onderzoekscentrum kernenergie De Laka-bibliotheek The Laka-library Dit is een pdf van één van de publicaties in This is a PDF from one of the publications de bibliotheek van Stichting Laka, het in from the library of the Laka Foundation; the Amsterdam gevestigde documentatie- en Amsterdam-based documentation and onderzoekscentrum kernenergie. research centre on nuclear energy. Laka heeft een bibliotheek met ongeveer The Laka library consists of about 8,000 8000 boeken (waarvan een gedeelte dus ook books (of which a part is available as PDF), als pdf), duizenden kranten- en tijdschriften- thousands of newspaper clippings, hundreds artikelen, honderden tijdschriftentitels, of magazines, posters, video's and other posters, video’s en ander beeldmateriaal. material. Laka digitaliseert (oude) tijdschriften en Laka digitizes books and magazines from the boeken uit de internationale antikernenergie- international movement against nuclear beweging. power. De catalogus van de Laka-bibliotheek staat The catalogue of the Laka-library can be op onze site. De collectie bevat een grote found at our website. The collection also verzameling gedigitaliseerde tijdschriften uit contains a large number of digitized de Nederlandse antikernenergie-beweging en magazines from the Dutch anti-nuclear power een verzameling video's. movement and a video-section. Laka speelt met oa. haar informatie- Laka plays with, amongst others things, its voorziening een belangrijke rol in de information services, an important role in the Nederlandse anti-kernenergiebeweging. Dutch anti-nuclear movement. Appreciate our work? Feel free to make a small donation. Thank you. www.laka.org | [email protected] | Ketelhuisplein 43, 1054 RD Amsterdam | 020-6168294 Woodhead Publishing is an imprint of Elsevier The Officers’ Mess Business Centre, Royston Road, Duxford, CB22 4QH, UK 50 Hampshire Street, 5th Floor, Cambridge, MA 02139, USA The Boulevard, Langford Lane, Kidlington, OX5 1GB, UK Copyright © 2016 Elsevier Ltd.