Gravity Concentration in Artisanal Gold Mining
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From Base Metals and Back – Isamills and Their Advantages in African Base Metal Operations
The Southern African Institute of Mining and Metallurgy Base Metals Conference 2013 H. de Waal, K. Barns, and J. Monama From base metals and back – IsaMills and their advantages in African base metal operations H. de Waal, K. Barns, and J. Monama Xstrata IsaMill™ technology was developed from Netzsch Feinmahltechnik GmbH stirred milling technology in the early 1990s to bring about a step change in grinding efficiency that was required to make Xstrata’s fine-grained lead/zinc orebodies economic to process. From small-scale machines suited to ultrafine grinding, the IsaMill™ has developed into technology that is able to treat much larger tonnages, in coarser applications, while still achieving high energy efficiency, suited for coarser more standard regrind and mainstream grinding applications. The unique design of the IsaMillTM, combining high power intensity and effective internal classification, achieves high energy efficiency and tight product distribution which can be effectively scaled from laboratory scale to full-sized models. The use of fine ceramic media also leads to significant benefits in downstream flotation and leaching operations. These benefits are key drivers for the adoption of the technology into processing a diverse range of minerals worldwide, and offer major opportunities for power reduction and improved metallurgy for the African base metal operations. Keywords: IsaMill, regrind, energy efficiency, inert grinding. Introduction The development of the IsaMillTM, by MIM (now GlencoreXstrata) and Netzsch Feinmahltechnik GmbH, was initiated to enable the development of the fine-grained ore deposits at Mt Isa and McArthur River in Northern Australia. To liberate the valuable minerals and so produce a saleable concentrate this ultrafine-grained ore needed to be ground to a P80 of 7 μm. -
Contents 2009
INNEHÅLLSFÖRTECKNING/CONTENTS Page Forssberg, Eric, Luleå University of Technology Energy in mineral beneficiation 1 Acarkan N., Kangal O., Bulut G., Önal G. Istanbul Technical University The comparison of gravity separation and flotation of gold and silver bearing ore 3 Ellefmo, Steinar & Ludvigsen, Erik, Norwegian University of Science and Technology Geological Modelling in a Mineral Resources Management Perspective 15 Hansson, Johan, Sundkvist, Jan-Eric, Bolin, Nils Johan, Boliden Mineral AB A study of a two stage removal process 25 Hulthén, Erik & Evertsson, Magnus, Chalmers University of Technology Optimization of crushing stage using on-line speed control on a cone crusher 37 Hooey1, P.L., Spiller2, D.E, Arvidson3, B.R., Marsden4, P., Olsson5, E., 1MEFOS, 2Eric Spiller Consultants LLC, 3Bo Arvidson Consulting LLC, 4, 5Northland Resources Inc. Metallurgical development of Northland Resources' IOCG resources 47 Ikumapayi, Fatai K., Luleå University of Technology, Sundkvist, Jan-Eric & Bolin, Nils-Johan, Boliden Mineral AB Treatment of process water from molybdenum flotation 65 Johansson, Björn, Boliden Mineral AB Limitations in the flotation process 79 Kongas, Matti & Saloheimo, Kari, Outotec Minerals Oy New innovations in on-stream analysis for flotation circuit management and control 89 Kuyumcu, Halit Z. & Rosenkranz, Jan, TU Berlin Investigation of Fluff Separation from Granulated Waste Plastics to be Used in 99 Blast Furnace Operation Mickelsson1, K-O, Östling2 J, Adolfsson3, G., 1LKAB Malmberget, 2Optimation AB Luleå, 3LKAB Kiruna -
Mineral Processing
Mineral Processing Foundations of theory and practice of minerallurgy 1st English edition JAN DRZYMALA, C. Eng., Ph.D., D.Sc. Member of the Polish Mineral Processing Society Wroclaw University of Technology 2007 Translation: J. Drzymala, A. Swatek Reviewer: A. Luszczkiewicz Published as supplied by the author ©Copyright by Jan Drzymala, Wroclaw 2007 Computer typesetting: Danuta Szyszka Cover design: Danuta Szyszka Cover photo: Sebastian Bożek Oficyna Wydawnicza Politechniki Wrocławskiej Wybrzeze Wyspianskiego 27 50-370 Wroclaw Any part of this publication can be used in any form by any means provided that the usage is acknowledged by the citation: Drzymala, J., Mineral Processing, Foundations of theory and practice of minerallurgy, Oficyna Wydawnicza PWr., 2007, www.ig.pwr.wroc.pl/minproc ISBN 978-83-7493-362-9 Contents Introduction ....................................................................................................................9 Part I Introduction to mineral processing .....................................................................13 1. From the Big Bang to mineral processing................................................................14 1.1. The formation of matter ...................................................................................14 1.2. Elementary particles.........................................................................................16 1.3. Molecules .........................................................................................................18 1.4. Solids................................................................................................................19 -
A History of Tailings1
A HISTORY OF MINERAL CONCENTRATION: A HISTORY OF TAILINGS1 by Timothy c. Richmond2 Abstract: The extraction of mineral values from the earth for beneficial use has been a human activity- since long before recorded history. Methodologies were little changed until the late 19th century. The nearly simultaneous developments of a method to produce steel of a uniform carbon content and the means to generate electrical power gave man the ability to process huge volumes of ores of ever decreasing purity. The tailings or waste products of mineral processing were traditionally discharged into adjacent streams, lakes, the sea or in piles on dry land. Their confinement apparently began in the early 20th century as a means for possible future mineral recovery, for the recycling of water in arid regions and/or in response to growing concerns for water pollution control. Additional Key Words: Mineral Beneficiation " ... for since Nature usually creates metals in an impure state, mixed with earth, stones, and solidified juices, it is necessary to separate most of these impurities from the ores as far as can be, and therefore I will now describe the methods by which the ores are sorted, broken with hammers, burnt, crushed with stamps, ground into powder, sifted, washed ..•. " Agricola, 1550 Introduction identifying mining wastes. It is frequently used mistakenly The term "tailings" is to identify all mineral wastes often misapplied when including the piles of waste rock located at the mouth of 1Presented at the 1.991. National mine shafts and adi ts, over- American. Society for Surface burden materials removed in Mining and Reclamation Meeting surface mining, wastes from in Durango, co, May 1.4-17, 1.991 concentrating activities and sometimes the wastes from 2Timothy c. -
Mineral Beneficiation Contents
Lecture 10: Mineral Beneficiation Contents: Preamble What constitutes mineral beneficiation Size reduction technology Concentration technologies: Basics Recovery and grade Separation efficiency Illustration on separation efficiency Concentration methods Conclusions References Keywords: mineral beneficiation, Milling, gravity concentration flotation Preamble Mineral beneficiation is the first step in extraction of metal from natural resources. With the depletion of high grade metal ores it is important to increase the metal grade of an ore by physical methods; which are termed mineral beneficiation .The objectives of mineral beneficiation are • To increase the metal grade of ore • To reduce the amount of gangue minerals so that lower volume of slag forms in pyromettallurgical extraction of metals .Slag contains mostly gangue minerals. • To decrease the thermal energy required to separate liquid metal from gangue minerals. • To decrease the aqueous solution requirement in hydrometturgical extraction of metals. In this lecture, mineral beneficiation science and technology are briefly reviewed so that readers can apply materials balance principles. Details about the mineral beneficiation can be studied in the reference given in this lecture. What constitutes mineral beneficiation? Ore is an aggregate of minerals and contains valuable and gangue minerals .The mineral beneficiation involves separations of gangue minerals from ore and is done in the following two stages: 1. Liberation of valuable mineral by size reduction technologies. In most ores the valuable minerals is distributed in the matrix of ore. 2. Concentration technologies to separate the gangue minerals and to achieve increase in the content of the valuable mineral to increase the metal grade. Sizes reduction technologies Size reduction or communication is an important step and may be used 9 To produce particles of required sizes and shapes 9 To liberate valuable mineral so that it can be concentrated. -
Isamill™ Technology Used in Efficient Grinding Circuits
1 IsaMill™ Technology Used in Efficient Grinding Circuits B.D. Burford1 and L.W. Clark2 High intensity stirred milling is now an industry accepted method to efficiently grind fine and coarse particles. In particular, the IsaMill™, which was invented for, and transformed the fine grinding industry, is now being included in many new comminution circuits in coarser applications. While comminution has always been regarded as important from a processing perspective, the pressure being applied by environmental concerns on all large scale power users, now make highly energy efficient processes more important than ever. The advantages that were developed in fine grinding in the early IsaMill™ installations have been carried over into coarse grinding applications. These advantages include a simple grinding circuit that operates in open circuit with a small footprint, the ability to offer sharp product size classification, as well as the use of inert media in a high energy intensive environment. This paper will examine the use of IsaMill™ technology in fine grinding (P80 below 15 micron), and examine the use of the technology in conventional grinding applications (P80 20 - 150 µm). Recent installations will be examined, including fine and coarse grinding applications, as well as the recent test work that was undertaken using an IsaMill™ in a primary grinding circuit, and the resulting circuit proposal for this site. While comminution has been relatively unchanged for the last century, the need to install energy efficient technology will promote further growth in IsaMill™ installations, and result in one of the biggest challenges to traditional comminution design. 1. Senior Process Engineer, Xstrata Technology, L4, 307 Queen Street, Brisbane 4000, Qld, Australia 2. -
Damage Cases and Environmental Releases from Mines and Mineral Processing Sites
DAMAGE CASES AND ENVIRONMENTAL RELEASES FROM MINES AND MINERAL PROCESSING SITES 1997 U.S. Environmental Protection Agency Office of Solid Waste 401 M Street, SW Washington, DC 20460 Contents Table of Contents INTRODUCTION Discussion and Summary of Environmental Releases and Damages ......................... Page 1 Methodology for Developing Environmental Release Cases ............................... Page 19 ARIZONA ASARCO Silver Bell Mine: "Waste and Process Water Discharges Contaminate Three Washes and Ground Water" ................................................... Page 24 Cyprus Bagdad Mine: "Acidic, Copper-Bearing Solution Seeps to Boulder Creek" ................................ Page 27 Cyprus Twin Buttes Mine: "Tank Leaks Acidic Metal Solution Resulting in Possible Soil and Ground Water Contamination" ...................................... Page 29 Magma Copper Mine: "Broken Pipeline Seam Causes Discharge to Pinal Creek" ................................ Page 31 Magma Copper Mine: "Multiple Discharges of Polluted Effluents Released to Pinto Creek and Its Tributaries" .................................................... Page 33 Magma Copper Mine: "Multiple Overflows Result in Major Fish Kill in Pinto Creek" ............................... Page 36 Magma Copper Mine: "Repeated Release of Tailings to Pinto Creek" .......................................... Page 39 Phelps Dodge Morenci Mine: "Contaminated Storm Water Seeps to Ground Water and Surface Water" ................................................................ Page 43 Phelps Dodge -
Identification and Description of Mineral Processing Sectors And
V. SUMMARY OF FINDINGS As shown in Exhibit 5-1, EPA determined that 48 commodity sectors generated a total of 527 waste streams that could be classified as either extraction/beneficiation or mineral processing wastes. After careful review, EPA determined that 41 com modity sectors generated a total of 354 waste streams that could be designated as mineral processing wastes. Exhibit 5-2 presents the 354 mineral processing wastes by commodity sector. Of these 354 waste streams, EPA has sufficient information (based on either analytical test data or engineering judgment) to determine that 148 waste streams are potentially RCRA hazardous wastes because they may exhibit one or more of the RCRA hazardous characteristics: toxicity, ignitability, corro sivity, or reactivity. Exhibit 5-3 presents the 148 RCRA hazardous mineral processing wastes that will be subject to the Land Disposal Restrictions. Exhibit 5-4 identifies the mineral processing commodity sectors that generate RCRA hazardous mineral processing wastes that are likely to be subject to the Land D isposal Restrictions. Exhibit 5-4 also summarizes the total number of hazardous waste streams by sector and the estimated total volume of hazardous wastes generated annually. At this time, however, EPA has insufficient information to determine whether the following nine sectors also generate wastes that could be classified as mineral processing wastes: Bromine, Gemstones, Iodine, Lithium, Lithium Carbonate, Soda Ash, Sodium Sulfate, and Strontium. -
National Instrument 43-101 Technical Report
ASANKO GOLD MINE – PHASE 1 DEFINITIVE PROJECT PLAN National Instrument 43-101 Technical Report Prepared by DRA Projects (Pty) Limited on behalf of ASANKO GOLD INC. Original Effective Date: December 17, 2014 Amended and Restated Effective January 26, 2015 Qualified Person: G. Bezuidenhout National Diploma (Extractive Metallurgy), FSIAMM Qualified Person: D. Heher B.Sc Eng (Mechanical), PrEng Qualified Person: T. Obiri-Yeboah, B.Sc Eng (Mining) PrEng Qualified Person: J. Stanbury, B Sc Eng (Industrial), Pr Eng Qualified Person: C. Muller B.Sc (Geology), B.Sc Hons (Geology), Pr. Sci. Nat. Qualified Person: D.Morgan M.Sc Eng (Civil), CPEng Asanko Gold Inc Asanko Gold Mine Phase 1 Definitive Project Plan Reference: C8478-TRPT-28 Rev 5 Our Ref: C8478 Page 2 of 581 Date and Signature Page This report titled “Asanko Gold Mine Phase 1 Definitive Project Plan, Ashanti Region, Ghana, National Instrument 43-101 Technical Report” with an effective date of 26 January 2015 was prepared on behalf of Asanko Gold Inc. by Glenn Bezuidenhout, Douglas Heher, Thomas Obiri-Yeboah, Charles Muller, John Stanbury, David Morgan and signed: Date at Gauteng, South Africa on this 26 day of January 2015 (signed) “Glenn Bezuidenhout” G. Bezuidenhout, National Diploma (Extractive Metallurgy), FSIAMM Date at Gauteng, South Africa on this 26 day of January 2015 (signed) “Douglas Heher” D. Heher, B.Sc Eng (Mechanical), PrEng Date at Gauteng, South Africa on this 26 day of January 2015 (signed) “Thomas Obiri-Yeboah” T. Obiri-Yeboah, B.Sc Eng (Mining) PrEng Date at Gauteng, South Africa on this 26 day of January 2015 (signed) “Charles Muller” C. -
How to Recover Ultra-Fine Particles
How to Recover Ultra-Fine Particles 1. BACKGROUND There is no controversy around the fact that mineral processing keeps getting harder and harder. Mineral deposits are getting more challenging and complex as mining companies are forced to bring new, low quality mines into production and try to squeeze as much as they can out of the long- neglected nether regions of existing ore bodies. Increasingly there is also a mandate to get more out of each tonne of ore processed and the focus often falls on fine (-75 micron) and ultra-fine (-38 micron) particles that historically might have been sent straight to the tailings dam. Why send these particles straight to the tailings dam? There are several problems that fine and ultra- fine particles can cause depending on the process. In gold leaching operations they can cause carbon fouling or interfere with Merrill-Crowe. Fines are notorious for being difficult to selectively float as well as degrading the selective flotation of coarser particles when they are intermixed. Filtration capacity is dramatically decreased when fines are present. With the exception of cyanide leaching for gold, fine and ultra-fines have traditionally proven to be very difficult to selectively recovery. Combining the process issues with challenges in selective recovery, many mines simply make the decision to remove the fines early in the process and send them straight to tailings. In fact, we have seen tin, tungsten and tantalum mines reject more than 10% of the target mineral in slime reject streams. ide Recovery (%) Recovery ide ph l Su Particle Size (microns) Figure 1: Sulphide flotation on 2 different ores (Feng & Aldrich, 1999) 2. -
Stillwater Mine, 45°23'N, 109°53'W East Boulder Mine, 45°30'N, 109°05'W
STILLWATER MINING COMPANY TECHNICAL REPORT FOR THE MINING OPERATIONS AT STILLWATER MINING COMPANY STILLWATER MINE, 45°23'N, 109°53'W EAST BOULDER MINE, 45°30'N, 109°05'W (BEHRE DOLBEAR PROJECT 11-030) MARCH 2011 PREPARED BY: MR. DAVID M. ABBOTT, JR., CPG DR. RICHARD L. BULLOCK, P.E. MS. BETTY GIBBS MR. RICHARD S. KUNTER BEHRE DOLBEAR & COMPANY, LTD. 999 Eighteenth Street, Suite 1500 Denver, Colorado 80202 (303) 620-0020 A Member of the Behre Dolbear Group Inc. © 2011, Behre Dolbear Group Inc. All Rights Reserved. www.dolbear.com Technical Report for the Mining Operations at Stillwater Mining Company March 2011 TABLE OF CONTENTS 3.0 SUMMARY ..................................................................................................................................... 1 3.1 INTRODUCTION .............................................................................................................. 1 3.2 EXPLORATION ................................................................................................................ 1 3.3 GEOLOGY AND MINERALIZATION ............................................................................ 2 3.4 DRILLING, SAMPLING METHOD, AND ANALYSES ................................................. 3 3.5 RESOURCES AND RESERVES ....................................................................................... 3 3.6 DEVELOPMENT AND OPERATIONS ........................................................................... 5 3.6.1 Mining Operation .................................................................................................. -
On the Association of Palladium-Bearing Gold, Hematite and Gypsum in an Ouro Preto Nugget
473 The Canadian Mineralogist Vol. 41, pp. 473-478 (2003) ON THE ASSOCIATION OF PALLADIUM-BEARING GOLD, HEMATITE AND GYPSUM IN AN OURO PRETO NUGGET ALEXANDRE RAPHAEL CABRAL§ AND BERND LEHMANN Institut für Mineralogie und Mineralische Rohstoffe, Technische Universität Clausthal, Adolph-Roemer-Str. 2A, D-38678 Clausthal-Zellerfeld, Germany ROGERIO KWITKO-RIBEIRO§ Centro de Desenvolvimento Mineral, Companhia Vale do Rio Doce, Rodovia BR 262/km 296, Caixa Postal 09, 33030-970 Santa Luzia – MG, Brazil RICHARD D. JONES 1636 East Skyline Drive, Tucson, Arizona 85178, U.S.A. ORLANDO G. ROCHA FILHO Mina do Gongo Soco, Companhia Vale do Rio Doce, Fazenda Gongo Soco, Caixa Postal 22, 35970-000 Barão de Cocais – MG, Brazil ABSTRACT An ouro preto (black gold) nugget from Gongo Soco, Minas Gerais, Brazil, has a mineral assemblage of hematite and gypsum hosted by Pd-bearing gold. The hematite inclusion is microfractured and stretched. Scattered on the surface of the gold is a dark- colored material that consists partially of Pd–O with relics of palladium arsenide-antimonides, compositionally close to isomertieite and mertieite-II. The Pd–O coating has considerable amounts of Cu, Fe and Hg, and a variable metal:oxygen ratio, from O-deficient to oxide-like compounds. The existence of a hydrated Pd–O compound is suggested, and its dehydration or deoxygenation at low temperatures may account for the O-deficient Pd-rich species, interpreted as a transient phase toward native palladium. Although gypsum is a common mineral in the oxidized (supergene) zones of gold deposits, the hematite–gypsum- bearing palladian gold nugget was tectonically deformed under brittle conditions and appears to be of low-temperature hydrother- mal origin.