Locating and Estimating Air Emissions from Sources of Lead and Lead Compounds
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Significance of Mineralogy in the Development of Flowsheets for Processing Uranium Ores
JfipwK LEACHING TIME REAGENTS TEMPERATURE FLOCCULANT CLARITY AREA COUNTER CURRENT DECANTATION It 21 21 J^^LJt TECHNICAL REPORTS SERIES No.19 6 Significance of Mineralogy in the Development of Flowsheets for Processing Uranium Ores \W# INTERNATIONAL ATOMIC ENERGY AGENCY, VIENNA, 1980 SIGNIFICANCE OF MINERALOGY IN THE DEVELOPMENT OF FLOWSHEETS FOR PROCESSING URANIUM ORES The following States are Members of the International Atomic Energy Agency: AFGHANISTAN HOLY SEE PHILIPPINES ALBANIA HUNGARY POLAND ALGERIA ICELAND PORTUGAL ARGENTINA INDIA QATAR AUSTRALIA INDONESIA ROMANIA AUSTRIA IRAN SAUDI ARABIA BANGLADESH IRAQ SENEGAL BELGIUM IRELAND SIERRA LEONE BOLIVIA ISRAEL SINGAPORE BRAZIL ITALY SOUTH AFRICA BULGARIA IVORY COAST SPAIN BURMA JAMAICA SRI LANKA BYELORUSSIAN SOVIET JAPAN SUDAN SOCIALIST REPUBLIC JORDAN SWEDEN CANADA KENYA SWITZERLAND CHILE KOREA, REPUBLIC OF SYRIAN ARAB REPUBLIC COLOMBIA KUWAIT THAILAND COSTA RICA LEBANON TUNISIA CUBA LIBERIA TURKEY CYPRUS LIBYAN ARAB JAMAHIRIYA UGANDA CZECHOSLOVAKIA LIECHTENSTEIN UKRAINIAN SOVIET SOCIALIST DEMOCRATIC KAMPUCHEA LUXEMBOURG REPUBLIC DEMOCRATIC PEOPLE'S MADAGASCAR UNION OF SOVIET SOCIALIST REPUBLIC OF KOREA MALAYSIA REPUBLICS DENMARK MALI UNITED ARAB EMIRATES DOMINICAN REPUBLIC MAURITIUS UNITED KINGDOM OF GREAT ECUADOR MEXICO BRITAIN AND NORTHERN EGYPT MONACO IRELAND EL SALVADOR MONGOLIA UNITED REPUBLIC OF ETHIOPIA MOROCCO CAMEROON FINLAND NETHERLANDS UNITED REPUBLIC OF FRANCE NEW ZEALAND TANZANIA GABON NICARAGUA UNITED STATES OF AMERICA GERMAN DEMOCRATIC REPUBLIC NIGER URUGUAY GERMANY, FEDERAL REPUBLIC OF NIGERIA VENEZUELA GHANA NORWAY VIET NAM GREECE PAKISTAN YUGOSLAVIA GUATEMALA PANAMA ZAIRE HAITI PARAGUAY ZAMBIA PERU The Agency's Statute was approved on 23 October 1956 by the Conference on the Statute of the IAEA held at United Nations Headquarters, New York; it entered into force on 29 July 1957. -
A Review of Flotation Separation of Mg Carbonates (Dolomite and Magnesite)
minerals Review A Review of Flotation Separation of Mg Carbonates (Dolomite and Magnesite) Darius G. Wonyen 1,†, Varney Kromah 1,†, Borbor Gibson 1,† ID , Solomon Nah 1,† and Saeed Chehreh Chelgani 1,2,* ID 1 Department of Geology and Mining Engineering, Faculty of Engineering, University of Liberia, P.O. Box 9020 Monrovia, Liberia; [email protected] (D.G.W.); [email protected] (Y.K.); [email protected] (B.G.); [email protected] (S.N.) 2 Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI 48109, USA * Correspondence: [email protected]; Tel.: +1-41-6830-9356 † These authors contributed equally to the study. Received: 24 July 2018; Accepted: 13 August 2018; Published: 15 August 2018 Abstract: It is well documented that flotation has high economic viability for the beneficiation of valuable minerals when their main ore bodies contain magnesium (Mg) carbonates such as dolomite and magnesite. Flotation separation of Mg carbonates from their associated valuable minerals (AVMs) presents several challenges, and Mg carbonates have high levels of adverse effects on separation efficiency. These complexities can be attributed to various reasons: Mg carbonates are naturally hydrophilic, soluble, and exhibit similar surface characteristics as their AVMs. This study presents a compilation of various parameters, including zeta potential, pH, particle size, reagents (collectors, depressant, and modifiers), and bio-flotation, which were examined in several investigations into separating Mg carbonates from their AVMs by froth flotation. Keywords: dolomite; magnesite; flotation; bio-flotation 1. Introduction Magnesium (Mg) carbonates (salt-type minerals) are typical gangue phases associated with several valuable minerals, and have complicated processing [1,2]. -
Calcination) 2
Thermal Treatment of Catalysts Modern Methods in Heterogeneous Catalysis Research Friederike C. Jentoft, October 31, 2003 Outline 1. Terminology (calcination) 2. Sample vs. oven set temperature 3. Self-generated atmosphere & self-steaming of zeolites 4. Combustion 5. Glow phenomenon & zirconia catalysts 6. Crystallization 7. Loss of surface area 8. Effect of additives 9. Solid-solid wetting 10.Reductive treatments & SMSI Steps of Catalyst Preparation v IUPAC defines 3 steps of catalyst preparation 1. Preparation of primary solid, associating all the useful compounds 2. Processing of that primary solid to obtain the catalyst precursor for example by heat treatment 3. Activation of the precursor to give the active catalyst (reduction to metal, formation of sulfides, deammoniation of zeolites) Heat Treatment of Intermediate Solids or Precursors v drying v thermal decomposition of salts (nitrates, ammonium salts) v calcination v product is a "reasonably inert solid" which can be stored easily Annealing v in a general meaning: a heating of a material over a long time span; strain and cracks in a crystalline solid can be removed Origin of the Term "Calcination" v latin "calx" = playstone limestone, (greek chálix) v burning of calcium carbonate (limestone) to calcium oxide (quicklime) -1 CaCO3 → CaO + CO2 ΔH(900°C)=3010 kJ mol v used to construct Giza pyramids (ca. 2800 A.C.), burning of limestone ("Kalkbrennen") mentioned by Cato 184 A.C. v performed in kilns (ovens) at 900°C v addition of air to sustain combustion + cool product Examples for -
Curbing Illicit Mercury and Gold Flows in West Africa: Options for a Regional Approach
Curbing Illicit Mercury and Gold Flows in West Africa: Options for a Regional Approach i INCLUSIVE AND SUSTAINABLE INDUSTRIAL DEVELOPMENT ii Curbing Illicit Mercury and Gold Flows in West Africa: Options for a Regional Approach iii November 2018 iv © UNIDO 2018. All rights reserved. This document has been produced without formal United Nations editing. The designations employed and the presentation of the material in this document do not imply the expression of any opinion whatsoever on the part of the Secretariat of the United Nations Industrial Development Organization (UNIDO) concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries, or its economic system or degree of development. Designations such as ‘developed’, ‘industrialized’ or ‘developing’ are intended for statistical convenience and do not necessarily express a judgement about the stage reached by a particular country or area in the development process. Mention of firm names or commercial products does not constitute an endorsement by UNIDO. Unless otherwise men- tioned, all references to sums of money are given in United States dollars. References to ‘tons’ are to metric tons, unless otherwise stated. All photos © UNIDO unless otherwise stated. Cover photo by Sadibou Sylla Acknowledgements This report was authored by Marcena Hunter of the Global Initiative Against Transnational Organized Crime. The report is part of the United Nations Industrial Development Organization (UNIDO) project, funded by the Government of Switzerland, to assist the Economic Community of West African States (ECOWAS) in its early implementation of the Minamata Convention. More information about the Minamata Convention and UNIDO’s work can be found on UNIDO’s website <https://www.unido.org/mercury> or by emailing Gabriela Eigenmann at [email protected]. -
221 Gaas GRADED A
USOO6403874B1 (12) United States Patent (10) Patent No.: US 6,403,874 B1 Shakouri et al. (45) Date of Patent: *Jun. 11, 2002 (54) HIGH-EFFICIENCY HETEROSTRUCTURE OTHER PUBLICATIONS THERMONIC COOLERS N N. W. Ashcroft, et al., Solid State Physics, manual, 1976, pp. (75) Inventors: Ali Shakouri, Santa Cruz; John E. 318-319, 320-321, 362-363. Bowers, Santa Barbara, both of CA D. A. Broido et al., “Effect of Superlattice structure on the (US) th ermoelectriclectric fiIlgure OIf meril:t: , Theline Am erican PhPinySIca 1 Society (Physical Review B.), vol. 51, No. 19, May 15, (73) Assignee: The Regents of the University of 1995, pp. 13797-800. California, Oakland, CA (US) D. A. Broido et al., “Comment of Use of quantum well Superlattices to obtain high figure of merit from nonconven (*) Notice: Subject to any disclaimer, the term of this tional thermoelectric materials”, Appl. Phys. Lett. 63, 3230 patent is extended or adjusted under 35 (1993), Applied Physics Letters, vol. 67, No. 8, Aug. 21, U.S.C. 154(b) by 0 days. 1995, pp. 1170–1171. D. A. Broido et al., “Thermoelectric figure or merit of This patent is Subject to a terminal dis- quantum wire Superlattices”, Applied Physics Letters, Jul. 3, claimer. 1995, vol. 67, No. 1, 100-102. (21) Appl. No.: 09/441,787 (List continued on next page.) (22) Filed: Nov. 17, 1999 Primary Examiner—Bruce F. Bell ASSistant Examiner Thomas H Parsons Related U.S. Application Data (74) Attorney, Agent, or Firm-Gates & Cooper LLP (60) Pisional application No. 60/109,342, filed on Nov. -
ITP Metal Casting: Advanced Melting Technologies
Advanced Melting Technologies: Energy Saving Concepts and Opportunities for the Metal Casting Industry November 2005 BCS, Incorporated 5550 Sterrett Place, Suite 306 Columbia, MD 21044 www.bcs-hq.com Advanced Melting Technologies: Energy Saving Concepts and Opportunities for the Metal Casting Industry Prepared for ITP Metal Casting by BCS, Incorporated November 2005 Acknowledgments This study was a collaborative effort by a team of researchers from University of Missouri–Rolla, Case Western Reserve University, and Carnegie Mellon University with BCS, Incorporated as the project coordinator and lead. The research findings for the nonferrous casting industry were contributed by Dr. Jack Wallace and Dr. David Schwam, while the ferrous melting technologies were addressed by Dr. Kent Peaslee and Dr. Richard Fruehan. BCS, Incorporated researched independently to provide an overview of the melting process and the U.S. metal casting industry. The final report was prepared by Robert D. Naranjo, Ji-Yea Kwon, Rajita Majumdar, and William T. Choate of BCS, Incorporated. We also gratefully acknowledge the support of the U.S. Department of Energy and Cast Metal Coalition (CMC) in conducting this study. 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 any of their employees, makes any warranty, expressed 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. -
AP-42, CH 12.9: Secondary Copper Smelting
12.9SecondaryCopperSmelting 12.9.1General1,2 Asof1992,morethan40percentoftheU.S.supplyofcopperisderivedfromsecondary sources,includingsuchitemsasmachineshoppunchings,turnings,andborings;manufacturingfacility defectiveorsurplusgoods;automobileradiators,pipes,wires,bushings,andbearings;and metallurgicalprocessskimmingsanddross.Thissecondarycoppercanberefinedintorelativelypure metalliccopper,alloyedwithzincortintoformbrassorbronze,incorporatedintochemicalproducts, orusedinanumberofsmallerapplications.Sixsecondarycoppersmeltersareinoperationinthe U.S.:3inIllinoisand1eachinGeorgia,Pennsylvania,andSouthCarolina.Alargenumberofmills andfoundriesreclaimrelativelypurecopperscrapforalloyingpurposes. 12.9.2ProcessDescription2,3 Secondarycopperrecoveryisdividedinto4separateoperations:scrappretreatment,smelting, alloying,andcasting.Pretreatmentincludesthecleaningandconsolidationofscrapinpreparationfor smelting.Smeltingconsistsofheatingandtreatingthescrapforseparationandpurificationofspecific metals.Alloyinginvolvestheadditionof1ormoreothermetalstocoppertoobtaindesirable qualitiescharacteristicofthecombinationofmetals.Themajorsecondarycoppersmeltingoperations areshowninFigure12.9-1;brassandbronzealloyingoperationsareshowninFigure12.9-2. 12.9.2.1Pretreatment- Scrappretreatmentmaybeachievedthroughmanual,mechanical,pyrometallurgical,or hydrometallurgicalmethods.Manualandmechanicalmethodsincludesorting,stripping,shredding, andmagneticseparation.Thescrapmaythenbecompressedintobricquettesinahydraulicpress. Pyrometallurgicalpretreatmentmayincludesweating(theseparationofdifferentmetalsbyslowly -
Application of a Central Composite Design for the Study of Nox Emission Performance of a Low Nox Burner
Energies 2015, 8, 3606-3627; doi:10.3390/en8053606 OPEN ACCESS energies ISSN 1996-1073 www.mdpi.com/journal/energies Article Application of a Central Composite Design for the Study of NOx Emission Performance of a Low NOx Burner Marcin Dutka 1,*, Mario Ditaranto 2,† and Terese Løvås 1,† 1 Department of Energy and Process Engineering, Norwegian University of Science and Technology, Kolbjørn Hejes vei 1b, Trondheim 7491, Norway; E-Mail: [email protected] 2 SINTEF Energy Research, Sem Sælands vei 11, Trondheim 7034, Norway; E-Mail: [email protected] † These authors contributed equally to this work. * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +47-41174223. Academic Editor: Jinliang Yuan Received: 24 November 2014 / Accepted: 22 April 2015 / Published: 29 April 2015 Abstract: In this study, the influence of various factors on nitrogen oxides (NOx) emissions of a low NOx burner is investigated using a central composite design (CCD) approach to an experimental matrix in order to show the applicability of design of experiments methodology to the combustion field. Four factors have been analyzed in terms of their impact on NOx formation: hydrogen fraction in the fuel (0%–15% mass fraction in hydrogen-enriched methane), amount of excess air (5%–30%), burner head position (20–25 mm from the burner throat) and secondary fuel fraction provided to the burner (0%–6%). The measurements were performed at a constant thermal load equal to 25 kW (calculated based on lower heating value). Response surface methodology and CCD were used to develop a second-degree polynomial regression model of the burner NOx emissions. -
S Ndlovu (PDF)
Extraction of Gold Then, Now and the Future Prof Sehliselo Ndlovu DST/NRF SARChI: Hydrometallurgy and Sustainable Development University of the Witwatersrand, Johannesburg Building a Robust Minerals Industry 3 – 4 July 2017, Cresta Lodge, Harare University of the Witwatersrand Johannesburg Founded Oct. 1896: School of Mines Approx. 37 000 Students 5 Faculties, 33 Schools, 3610 Courses >160 000 Degrees Conferred since 1922 55% Female Students 10 National Centres of Excellence Home to the Bidvest Football Club( Current PSL league Champions) Evolution in Gold Processing Past Technologies • Amalgamation • Panning Current Technologies • Cyanide leaching • Processing of Emerging and Future refractory ores Technologies • Bio-oxidation • Ionic liquids • Alternative leaching • Ultrasonic leaching reagents • Corn starch?? Past Technologies Used in Ancient Times History of gold extends back at least 6,000 years. Egypt and Mesopotamia around 4000 BC. Gravity Separation: Gold Panning Gold concentrated by washing lighter river sands with water Leaves dense gold particles Alternative- wash gold-bearing sand and gravel over a woollen fleece Traps heavier gold dust that would sink into the wool fibres. Advantages • Simplicity Disadvantages • Labour intensive Gravity Separation: Sluicing • Water is channelled to flow through a sluice-box. • Sluice-box is essentially a man-made channel with riffles (barriers) at the bottom. • Riffles create dead-zones in the water current which allows gold to drop out of suspension. Sluicing and panning results in the direct recovery of small gold nuggets and flakes. Gold Parting: Salt Cementation Process • Invented to remove Ag from Au-Ag mixtures around 6th century BC. Mix: argentiferous gold foil, common salt, brick dust or burnt clay and urine in a sealed container. -
Recommendations for Design Parameters for Central Composite Designs with Restricted Randomization
Recommendations for Design Parameters for Central Composite Designs with Restricted Randomization Li Wang Dissertation submitted to the Faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Statistics Geoff Vining, Chair Scott Kowalski, Co-Chair John P. Morgan Dan Spitzner Keying Ye August 15, 2006 Blacksburg, Virginia Keywords: Response Surface Designs, Central Composite Design, Split-plot Designs, Rotatability, Orthogonal Blocking. Copyright 2006, Li Wang Recommendations for Design Parameters for Central Composite Designs with Restricted Randomization Li Wang ABSTRACT In response surface methodology, the central composite design is the most popular choice for fitting a second order model. The choice of the distance for the axial runs, α, in a central composite design is very crucial to the performance of the design. In the literature, there are plenty of discussions and recommendations for the choice of α, among which a rotatable α and an orthogonal blocking α receive the greatest attention. Box and Hunter (1957) discuss and calculate the values for α that achieve rotatability, which is a way to stabilize prediction variance of the design. They also give the values for α that make the design orthogonally blocked, where the estimates of the model coefficients remain the same even when the block effects are added to the model. In the last ten years, people have begun to realize the importance of a split-plot structure in industrial experiments. Constructing response surface designs with a split-plot structure is a hot research area now. In this dissertation, Box and Hunters’ choice of α for rotatablity and orthogonal blocking is extended to central composite designs with a split-plot structure. -
Principles of Extractive Metallurgy Lectures Note
PRINCIPLES OF EXTRACTIVE METALLURGY B.TECH, 3RD SEMESTER LECTURES NOTE BY SAGAR NAYAK DR. KALI CHARAN SABAT DEPARTMENT OF METALLURGICAL AND MATERIALS ENGINEERING PARALA MAHARAJA ENGINEERING COLLEGE, BERHAMPUR DISCLAIMER This document does not claim any originality and cannot be used as a substitute for prescribed textbooks. The information presented here is merely a collection by the author for their respective teaching assignments as an additional tool for the teaching-learning process. Various sources as mentioned at the reference of the document as well as freely available material from internet were consulted for preparing this document. The ownership of the information lies with the respective author or institutions. Further, this document is not intended to be used for commercial purpose and the faculty is not accountable for any issues, legal or otherwise, arising out of use of this document. The committee faculty members make no representations or warranties with respect to the accuracy or completeness of the contents of this document and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. BPUT SYLLABUS PRINCIPLES OF EXTRACTIVE METALLURGY (3-1-0) MODULE I (14 HOURS) Unit processes in Pyro metallurgy: Calcination and roasting, sintering, smelting, converting, reduction, smelting-reduction, Metallothermic and hydrogen reduction; distillation and other physical and chemical refining methods: Fire refining, Zone refining, Liquation and Cupellation. Small problems related to pyro metallurgy. MODULE II (14 HOURS) Unit processes in Hydrometallurgy: Leaching practice: In situ leaching, Dump and heap leaching, Percolation leaching, Agitation leaching, Purification of leach liquor, Kinetics of Leaching; Bio- leaching: Recovery of metals from Leach liquor by Solvent Extraction, Ion exchange , Precipitation and Cementation process. -
Effect of Design Selection on Response Surface Performance
NASA Contractor Report 4520 Effect of Design Selection on Response Surface Performance William C. Carpenter University of South Florida Tampa, Florida Prepared for Langley Research Center under Grant NAG1-1378 National Aeronautics and Space Administration Office of Management Scientific and Technical Information Program 1993 Table of Contents lo Introduction ................................................. 1 1.10uality Qf Fit ............................................. 2 1.].1 Fit at the designs .................................... 2 1.1.2 Overall fit ......................................... 3 1.2. Polynomial Approximations .................................. 4 1.2.1 Exactly-determined approximation ....................... 5 1.2.2 Over-determined approximation ......................... 5 1.2.3 Under-determined approximation ........................ 6 1,3 Artificial Neural Nets ....................................... 7 1 Levels of Designs ............................................. 1O 2.1 Taylor Series Approximation ................................. 10 2,2 Example ................................................ 13 2.3 Conclu_iQn .............................................. 18 B Standard Designs ............................................ 19 3.1 Underlying Principle ....................................... 19 3.2 Statistical Concepts ....................................... 20 3.30rthogonal Designs ........................................ 23 ........................................... 24 3.3.1.1 Example of Scaled Designs: ....................