METE 256 ASSAYING – Ore Reserve Calculations – Control of Processes (Gravity Concentration) – Recovery Calculations – Smelter Schedule Dr

Total Page:16

File Type:pdf, Size:1020Kb

METE 256 ASSAYING – Ore Reserve Calculations – Control of Processes (Gravity Concentration) – Recovery Calculations – Smelter Schedule Dr 1/5/2017 Kwame Nkrumah University of Science & Technology, Kumasi, Ghana Course Objective • Determination of the constituents of ores and metallurgical products for: – prospecting METE 256 ASSAYING – ore reserve calculations – control of processes (gravity concentration) – recovery calculations – smelter schedule Dr. Anthony Andrews – bullion sales, etc Department of Materials Engineering Faculty of Mechanical and Chemical Engineering College of Engineering www.knust.edu.gh Course Outline Course Assessment • Sampling – Methods of sampling • Quizzes – 10 points – Sampling dividing techniques • Mid Exam – 20 points – Weight of samples relative to size of particles • Final Exam – 70 points • Statistical evaluation of data • Metallurgical testing – Bottle roll test, Column leach test, Acid digestion, Fire assaying, Diagnostic leaching • Characterization and instrumental methods of analyses www.knust.edu.gh www.knust.edu.gh Fire Assaying - Introduction Fire Assaying - Background • Many methods have been developed and refined over the years, but “Fire Assay” remains a favoured method for determining the • The particular fire assay method under discussion is total gold content of a sample. aimed only at measuring • In this method, a pulverised mineral sample is dissolved using heat Gold and Precious Metals and fluxing agents. • Precious metals are extracted from the melted material using • Variations of fire assay can be used for other metals, molten Lead (Pb). however, in most instances other analytical methods are favoured • The precious metals are then separated from the Lead in a secondary process called “cupellation”. • The gold content of the precious metals collected is then determined, using a variety of analytical techniques. www.knust.edu.gh www.knust.edu.gh 1 1/5/2017 Fire Assaying – Applications Traditional Fire Assay Method (After Sample Preparation) • Soil samples 1. Sub-sampling & Catch-weigh • Exploration drill samples 2. Fluxing 3. Firing • Grade control 4. Cooling & Separation 5. Cupellation • Mill solutions 6. Parting & Dissolution 7. Analysis • Tailings www.knust.edu.gh www.knust.edu.gh Sampling Significance of Sampling • A process of taking a portion from a bulk of material and using that portion to represent the bulk of material. • Convenience in size for transportation and testing Or • A sample is a small amount of material removed from a bulk, such that it contains all the components in the • Obtain the desired information at the smallest cost proportion in which they occur in the original lot. • Why Sample??? • Entire bulk may be inaccessible, too massive or too dangerous to deal with. E.g human blood www.knust.edu.gh www.knust.edu.gh Important Considerations in Categories of Sampling Sampling • Representative of the bulk • Exploratory – Samples taken during prospecting, exploration and proving of a • Results from analysis of the sample should be appropriate to mine predict the behaviour of the bulk • No sample can provide absolute information about the bulk • Controlled • Statistical technique – provide an estimate within probability limit – Samples taken to determine the content of specific constituents • All the components in the bulk should have equal chance of in a given environment reporting into the sample • Pre-sampling preparation to reduce biasness www.knust.edu.gh www.knust.edu.gh 2 1/5/2017 Principles of Sampling Methods for Sampling Material in a Lab • The distribution of values in an ore body is never Stratified or Unstratified uniform • When is this sampling • The results of the sampling shall represent as truly as technique used? possible the average metallic content of the ore/bulk • Where will you take a sample material from? • Each single sample must represent a true average of that portion of bulk from which it is taken www.knust.edu.gh www.knust.edu.gh Methods for Sampling Material in a Methods for Sampling Material in a Lab Lab Grab sample Random – chance • Simplest, quickest, and most • Where will you take a sample flexible method from? • It can be carried out on small quantities using spatulas, or on large quantities using shovels Systematic – orderly • This method uses the least Mixing a sample on a rolling mat. equipment, but also is the most • Where will you take a sample Mix by first drawing corner A so that prone to human biases and has a from? the sample rolls towards C, then higher variance between samples drawing corner B to corner D, then than other methods. drawing corner C to corner A, then corner D to corner B, then repeat. www.knust.edu.gh www.knust.edu.gh Methods for Sampling Material in a Sample Dividing Methods Lab Composite sample • The sample does not pass through the sample device and hence prone to error • Individual samples combined as single sample • Sample is taken from the surface where it may not be typical of the mass. Scoop sampling • Shake sample before sampling. www.knust.edu.gh www.knust.edu.gh 3 1/5/2017 Sample Dividing Methods Sample Dividing Methods Chute-Type Riffle Sampler Coning and quartering www.knust.edu.gh www.knust.edu.gh Sample Dividing Methods Comparison of Lab Sample Devices Rotary Riffle Splitter Standard Deviation of Sampling Method Samples (%) Cone & Quarter 6.81 Grab Sampling 5.14 Chute-Type Sample Splitter 1.01 Rotary Riffle 0.125 www.knust.edu.gh www.knust.edu.gh Sampling Problems and Sampling Problems and Requirements Requirements • Degree of representativeness is based on heterogeneity • Problems in sampling centers on: • Issues with variations in the distribution of components within the – Nature and efficiency of sampling process bulk such as: – Weight reduction in the lab – Size segregation – Correctness in the interpretation of data – Mineralogy – Reliability of results – Chemical composition – Accuracy of results – Grade – Precision of results – Moisture content – Biasness in sampling and measurement – Weight – Shape • Incorrectness of the above will result in sampling error www.knust.edu.gh www.knust.edu.gh 4 1/5/2017 Size effect on sample integrity Sampling Calculations using Gy’s Method • Mineralogy, grade and moisture content may vary with size • This method is a general-purpose calculation to determine the minimum size of sample needed to ensure that it will be • Bulk material …Gross sample…Lab…Measurement representative of the whole lot, within specified limits. – Samples for lab measurement are obtained by standard techniques – Samples for lab measurement can be size-biased Before using, approximate estimates of the following will be needed: • Coarse samples presents challenges in size volume reduction • The content of the species of interest in the lot (assay) • Smaller volume samples are more representative when particle • The general shape of the particles size is fine • The densities of the various species and phases present • The particle size distribution • The degree of liberation, and the grain size www.knust.edu.gh www.knust.edu.gh Sampling Calculations using Gy’s Sampling Calculations using Gy’s Method Method Basic Equation: Basic Equation: When W is much larger than M, the equation is simplified to: www.knust.edu.gh www.knust.edu.gh Gy’s Equation – Working out C Calculating with incomplete information 1 1 푆2 = 푓푔푙푚퐷3 − Make the following conservative assumptions: 푀 퐿 • f = 0.5 (normal blocky particles); Where C is fglm • g = 0.75 (narrow size distribution. Use g = 1 if the sample is • f= particle shape factor (describes the shape of the particles) obviously monosized and 0.25 for broad size distribution); • g= granulometric factor (describes how much variation there is • l = 1 (grains are as large as the particles) in the size of particles) • l = liberation factor (how close to liberation the material has • The value of m will still need to be calculated, based on your best been ground) estimate of the assay of the sample and the densities of the • m = mineralogical composition factor (describes how much of components of interest. a rock is made up of the element of interest at a given grade) www.knust.edu.gh www.knust.edu.gh 5 1/5/2017 Calculating with incomplete Calculating with incomplete information information • The liberation factor, l, is a measure of the degree of dispersion • The composition factor (m), is calculated from the formula: of the valuable material through the bulk, and of the homogeneity of the material. 1 − 푎 푚 = 1 − 푎 푟 + 푎푡 • It is calculated from the expression: 푎 퐿 푙 = 푑 Where: r = specific gravity of the valuable component t = specific gravity of the remainder of the material Where: a = fractional average assay of the valuable substance L = the size where the values are essentially completely liberated (grain size), cm d = sieve size www.knust.edu.gh www.knust.edu.gh Gy’s Equation Work Example • A sample of 200 g is to be taken and used for fire • Simplified version of Gy’s equation: assaying from a bulk sample of weight 5 kg with 푊 ≥ 125000푑3 average particle size 10 mm. How fine should the material be crushed before a representative sample can W = weight, g be taken? d = diameter of the largest particle (cm) www.knust.edu.gh www.knust.edu.gh Home Work Important Terminologies Bulk Materials Parameters: • Materials of Interest: CuFeS2 in a silica matrix, 1.5% Cu • Replicates: - samples of the same size that are carried through an (4.3318% CuFeS2); Top Size = 1.5 cm; CuFeS2 grain size = 0.01 analysis in exactly the same way. cm. • Precision: - the closeness of data to other data that have been obtained in exactly the same way. • Desired sampling accuracy: ±0.02% Cu, certainty of 0.99 (2.576 • Accuracy: - the correctness of measurement or closeness of a result standard deviations) to its true or accepted value. • Outlier: - an occasional result in replicate measurements that obviously differs significantly from the rest of the results. • CuFeS2 specific gravity = 4.2; Overall specific gravity = 2.8; Broad size distribution. • Bias: - a measures of the systematic error associated with an Determine the minimum sample weight (in grams) needed for analysis.
Recommended publications
  • 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.
    [Show full text]
  • Treatment and Microscopy of Gold
    TREATMENT AND MICROSCOPY OF GOLD AND BASE METAL ORES. (Script with Sketches & Tables) Short Course by R. W. Lehne April 2006 www.isogyre.com Geneva University, Department of Mineralogy CONTENTS (Script) page 1. Gold ores and their metallurgical treatment 2 1.1 Gravity processes 2 1.2 Amalgamation 2 1.3 Flotation and subsequent processes 2 1.4 Leaching processes 3 1.5 Gold extraction processes 4 1.6 Cyanide leaching vs. thio-compound leaching 5 2. Microscopy of gold ores and treatment products 5 2.1 Tasks and problems of microscopical investigations 5 2.2 Microscopy of selected gold ores and products 6 (practical exercises) 3. Base metal ores and their beneficiation 7 3.1 Flotation 7 3.2 Development of the flotation process 7 3.3 Principles and mechanisms of flotation 7 3.4 Column flotation 9 3.5 Hydrometallurgy 10 4. Microscopy of base metal ores and milling products 10 4.1 Specific tasks of microscopical investigations 11 4.2 Microscopy of selected base metal ores and milling products 13 (practical exercises) 5. Selected bibliography 14 (Sketches & Tables) Different ways of gold concentration 15 Gravity concentration of gold (Agricola) 16 Gravity concentration of gold (“Long Tom”) 17 Shaking table 18 Humphreys spiral concentrator 19 Amalgamating mills (Mexican “arrastra”, Chilean “trapiche”) 20 Pressure oxidation flowsheet 21 Chemical reactions of gold leaching and cementation 22 Cyanide solubilities of selected minerals 23 Heap leaching flowsheet 24 Carbon in pulp process 25 Complexing of gold by thio-compounds 26 Relation gold content / amount of particles in polished section 27 www.isogyre.com Economically important copper minerals 28 Common zinc minerals 29 Selection of flotation reagents 30 Design and function of a flotation cell 31 Column cell flotation 32 Flowsheet of a simple flotation process 33 Flowsheet of a selective Pb-Zn flotation 34 Locking textures 35 2 1.
    [Show full text]
  • Xstrata Technology Update Edition 13 – April 2012 Building Plants That Work
    xstrata technology update Edition 13 – April 2012 Building plants that work You have to get a lot of things it takes another operator to get them right to build a plant that works. right. Someone who has lived through the problems, had to do the maintenance, operated during a midnight power Of course the big picture must be right – doing the right project, in the right place, failure, cleaned up the spill. Someone at the right time. who has “closed the loop” on previous designs; lived with previous decisions After that, the devil is in the detail. You and improved them, over and over. need a sound design, good execution, good commissioning, and ongoing This is why Xstrata Technology provides support after commissioning. You need a technology “package”. Just as a car to operate and maintain your plant in is more than an engine, technology is the long run, long after the construction more than a single piece of equipment. company has left. That’s when all the Technology is a system. All the elements “little” details become important – how of the system have to work with each easy is it to operate, how good is the other and with the people in the plant. maintenance access, what happens in We want our cars designed by people a power failure, where are the spillage who love cars and driving. So should points and how do we clean them our plants be designed by people with up? Are the instruments reliable and experience and passion to make each is the process control strategy robust one work better than the last.
    [Show full text]
  • Copper Recovery Using Leach/Solvent Extraction/Electrowinning Technology
    Copper recovery using leach/solvent extraction/electrowinning technology: Forty years of innovation, 2.2 million tonnes of copper annually by G.A. Kordosky* small scale in analytical chemistry3 and on a large scale for the recovery of uranium from Synopsis sulphuric acid leach solutions4. Generally Mills had already developed and commercialized The concept of selectively extracting copper from a low-grade dump Alamine® 336 as an SX reagent for the leach solution followed by stripping the copper into an acid recovery of uranium from sulphuric acid leach solution from which electrowon copper cathodes could be produced liquors5 and believed that a similar technology occurred to the Minerals Group of General Mills in the early 1960s. for copper recovery would be welcome. This simple, elegant idea has resulted in a technology by which However, an extensive market survey showed about 2.2 million tonnes of high quality copper cathode was produced in year 2000. The growth of this technology is traced over that the industry reception for copper recovery time with a discussion of the key plants, the key people and the by L/SX/EW technology was almost hostile. important advances in leaching, plant design, reagents and The R&D director of a large copper producer electrowinning that have contributed to the growth of this predicted at an AIME annual meeting that technology. Some thoughts on potential further advances in the there would never be a pound of copper technology are also given. recovered using solvent extraction and his comment prompted
    [Show full text]
  • Pretreatment of Copper Ore Prior to Heap Leaching Includes Crushing and Agglomeration Processes Which Were Studied in This Thesis Research
    PRETREATMENT OF COPPER ORE PRIOR TO HEAP LEACHING by Phanindra Kodali A thesis submitted to the faculty of The University of Utah in partial fulfillment of the requirements for the degree of Master of Science Department of Metallurgical Engineering The University of Utah August 2010 Copyright Phanindra Kodali 2010 All Rights Reserved The University of Utah Graduate School STATEMENT OF THESIS APPROVAL The thesis of Phanindra Kodali has been approved by the following supervisory committee members: Jan D. Miller , Chair 11113/2009 Chen-Luh Lin , Member 11113/2009 Xuming Wang , Member 11113/2009 Michael S. Moats . Member 11113/2009 and by Jan D. Miller , Chair of the Department of Metallurgical Engineering and by Charles A. Wight, Dean of The Graduate School. ABSTRACT Pretreatment of copper ore prior to heap leaching includes crushing and agglomeration processes which were studied in this thesis research. Crushing is a high energy consuming process. In mining operations generally jaw and gyratory crushers are used for primary crushing and cone crushers are used for secondary crushing. During the past couple of decades High Pressure Grinding Roll (HPGR) crushers are being considered by mining companies due to lower energy consumption. In the present research copper ores (copper oxide and copper sulfide ores) were crushed by a jaw crusher and by HPGR and the products evaluated for particle damage, as well as by column leaching to determine the rate and extent of copper recovery. X-ray computed tomography analysis and laboratory column leaching experiments on copper oxide samples revealed that products from HPGR crushing have more particle damage and higher copper recoveries when compared with products from jaw crusher crushing.
    [Show full text]
  • In-Situ Chromium and Vanadium Recovery of Landfilled Ferrochromium
    Chemical Engineering Journal 303 (2016) 359–368 Contents lists available at ScienceDirect Chemical Engineering Journal journal homepage: www.elsevier.com/locate/cej In-situ chromium and vanadium recovery of landfilled ferrochromium and stainless steel slags ⇑ Jeroen Spooren a, , Eunyoung Kim a,b, Liesbeth Horckmans a, Kris Broos a, Peter Nielsen a, Mieke Quaghebeur a a VITO – Flemish Institute for Technological Research, Boeretang 200, B-2400 Mol, Belgium b Department of Bioengineering, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium highlights NaOCl assisted alkaline heap leaching of Cr and V from slags was investigated. The matrix material of stainless steel slag and ferrochromium slag remains intact. 11–19% Cr and 7.0–7.5% V were leached selectively after 64 days. A model shows that Cr will leach for 4–5 years at chosen heap leaching conditions. Cr and V extraction potentially improves the slags’ environmental quality. article info abstract Article history: A novel heap leaching method was investigated for selective removal of chromium (Cr) and vanadium (V) Received 26 March 2016 from ferrochromium (FeCr) and stainless steel (SS) slags. In particular, alkaline oxidative heap leaching Received in revised form 25 May 2016 was simulated on lab-scale by batch and column leaching tests. The results show a selective leaching Accepted 26 May 2016 of Cr (11–19%) and V (7.0–7.5%) after 64 days of column leaching, with a very low dissolution (<2.2% Available online 27 May 2016 (FeCr slag) and <0.15% (SS slag)) of matrix elements (e.g. Al, Fe, Si, Mg, Ca), when NaOCl is applied as oxi- dation agent and NaOH as alkaline agent.
    [Show full text]
  • Study of the Calcination Process of Two Limonitic Iron Ores Between 250 °C and 950 °C
    Lisbeth Longa-Avello - Cristina Pereyra-Zerpa - Julio Andrés Casal-Ramos - Pedro Delvasto Study of the calcination process of two limonitic iron ores between 250 °C and 950 °C Estudio del proceso de calcinación en dos minerales de hierro limoníticos entre 250 °C y 950 °C Estudo do processo de calcinação em dois minerais de ferro limoníticos entre 250 °C e 950 °C Lisbeth Longa-Avello* Cristina Pereyra-Zerpa** Fecha de recepción: 20 de septiembre de 2016 Julio Andrés Casal-Ramos*** Fecha de aprobación: 20 de marzo de 2017 Pedro Delvasto**** Abstract The dehydration process of two limonitic ores from Venezuela was studied between 250 °C and 950 °C by means of thermogravimetry, infrared spectroscopy, and x-ray diffraction. These techniques indicated for both minerals that the goethite-to-hematite transformation occurred in the range of 250-350 °C. In addition, the x-ray diffraction showed a structural re-arrangement within the orebody above 350 °C, temperature above which only the hematite structure is recognizable. Finally, infrared spectroscopy revealed that such transformation implies the loss of structural OH- functional groups, characteristic of the limonite. Keywords: Iron Ore; Limonite; Thermal Modification of Minerals. Resumen Se estudió el proceso de deshidratación de dos minerales limoníticos de Venezuela entre 250 °C y 950 °C, usando termogravimetría, espectroscopia infrarroja y difracción de rayos x. Para ambos materiales, estas técnicas indicaron que la transformación de goethita a hematita ocurrió en el rango de 250 °C a 350 °C. Adicionalmente, la difracción de rayos X mostró un rearreglo estructural dentro de la mena a una temperatura por encima de 350 °C; a temperaturas mayores, solo se reconoce la estructura de la hematita.
    [Show full text]
  • Extractive Metallurgy of Copper This Page Intentionally Left Blank Extractive Metallurgy of Copper
    Extractive Metallurgy of Copper This page intentionally left blank Extractive Metallurgy of Copper Mark E. Schlesinger Matthew J. King Kathryn C. Sole William G. Davenport AMSTERDAM l BOSTON l HEIDELBERG l LONDON NEW YORK l OXFORD l PARIS l SAN DIEGO SAN FRANCISCO l SINGAPORE l SYDNEY l TOKYO Elsevier The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, UK Radarweg 29, PO Box 211, 1000 AE Amsterdam, The Netherlands First edition 1976 Second edition 1980 Third edition 1994 Fourth edition 2002 Fifth Edition 2011 Copyright Ó 2011 Elsevier Ltd. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means electronic, mechanical, photocopying, recording or otherwise without the prior written permission of the publisher Permissions may be sought directly from Elsevier’s Science & Technology Rights Department in Oxford, UK: phone (+44) (0) 1865 843830; fax (+44) (0) 1865 853333; email: permissions@ elsevier.com. Alternatively you can submit your request online by visiting the Elsevier web site at http://elsevier.com/locate/permissions, and selecting Obtaining permission to use Elsevier material Notice No responsibility is assumed by the publisher for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions or ideas contained in the material herein British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging-in-Publication Data A catalog record for this book is available from the Library of Congress ISBN: 978-0-08-096789-9 For information on all Elsevier publications visit our web site at elsevierdirect.com Printed and bound in Great Britain 11 12 13 14 10 9 8 7 6 5 Photo credits: Secondary cover photograph shows anode casting furnace at Palabora Mining Company, South Africa.
    [Show full text]
  • Cyanide Heap-Leach Gold Mining and Its Impacts on the Environment
    l CYANIDE HEAP-LEACH GOLD MINING AND ITS IMPACTS ON THE ENVIRONMENT Prepared for: John C. Parks Senior Environmental Coordinator Atlas Precious Metals Inc. Princeton, New Jersey By... Diane Young Technical Writing Beth Camp, Instructor November 20, 1989 Diane Young 1405 Southwest Brooklane Drive Corvallis, Oregon 97333 November 20, 1989 Beth Camp Technical Writing Instructor Linn-Benton Community College Albany, Oregon 97321 Dear Beth, The purpose of "cyanide heap-leach gold mining and its impacts on the environment" is to introduce alternative mining techniques that will help alleviate wildlife death, and ground and surface water pollution due to cyanide ponds and leaks. Cyanide heap-leach gold mining is a process where micro-gold is extracted from ore. The ore is spread out in heaps and sprinkled with a dilute cyanide solution. The gold-laden or ''pregnant" cyanide is contained under the ore by plastic liners and a layer of clay. The "pregnant'' solution is pumped through a series of carbon columns which separates the gold from the cyanide. This cyanide solution is then sent to a "holding pond'' where it is restored to its former strength and later reused. Through library research and personal interviews, I have recommended that the following alternative systems be implemented. They are: -installing French drains and double liners for the detection of cyanide leaks, -installing nets and flags, and double fences for wildlife preservation. Atlas Mining Company's benefits will include improving relationships with environmental agencies,
    [Show full text]
  • 2015 US Bond
    NOTICE THIS OFFERING CIRCULAR IS AVAILABLE ONLY TO INVESTORS WHO ARE EITHER (1) QUALIFIED INSTITUTIONAL BUYERS WITHIN THE MEANING OF RULE 144A UNDER THE U.S. SECURITIES ACT OF 1933, AS AMENDED (THE “U.S. SECURITIES ACT”) OR (2) PERSONS WHO ARE NOT U.S. PERSONS (AS DEFINED IN REGULATION S UNDER THE U.S. SECURITIES ACT) AND WHO ARE OUTSIDE OF THE UNITED STATES IN ACCORDANCE WITH REGULATION S UNDER THE U.S. SECURITIES ACT (AND, IF INVESTORS ARE RESIDENT IN A MEMBER STATE OF THE EUROPEAN ECONOMIC AREA, A QUALIFIED INVESTOR). IMPORTANT: You must read the following before continuing. The following applies to the offering circular following this notice, whether received by email or otherwise received as a result of electronic communication. You are advised to read this disclaimer carefully before reading, accessing or making any other use of the offering circular. In accessing the offering circular, you agree to be bound by the following terms and conditions, including any modifications to them, each time you receive any information from us as a result of such access. NOTHING IN THIS ELECTRONIC TRANSMISSION CONSTITUTES AN OFFER OF SECURITIES FOR SALE IN ANY JURISDICTION WHERE IT IS UNLAWFUL TO DO SO. THE SECURITIES HAVE NOT BEEN, AND WILL NOT BE, REGISTERED UNDER THE U.S. SECURITIES ACT OR THE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES OR OTHER JURISDICTION AND THE SECURITIES MAY NOT BE OFFERED OR SOLD WITHIN THE UNITED STATES EXCEPT PURSUANT TO AN EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE U.S.
    [Show full text]
  • Nonoxidative Leaching of Non-Ferrous Metals from Wastes of Kola Mining by Sulphuric Acid
    International Journal of Mining Science (IJMS) Volume 1, Issue 1, June 2015, PP 17-24 www.arcjournals.org Nonoxidative Leaching of Non-ferrous Metals from Wastes of Kola Mining by Sulphuric Acid Anton Svetlov, Dmitry Makarov, Vladimir Vigdergauz 1Institute of Industrial North Ecology Problems of the Kola Science Centre of RAS, Fersman St., 14a, Apatity, Murmansk Region, Russia. [email protected] Abstract: Dressing tailings and metallurgical slags, while being a major source of non-ferrous metals, pose a serious environmental hazard if unprocessed. In this study, the leaching kinetics of copper and nickel from low- grade wastes of Kola Mining was investigated. Leaching experiments were conducted in sulfuric acid electrolyte at a room temperature. The output solutions were analyzed using the atom-absorption spectrometry and the solid phase was analyzed using X-ray diffraction. The dynamics of metal leaching in the experiment show that heap leaching is quite advantageous when re-extracting metals from pelletized copper-nickel ore dressing tailings of current production, or of lean additional concentrate of tailings flotation. Taking into account the availability of excess sulphuric acid turned out by the "Kola MMC" JSC enterprises, sulphatization of pellets, where H2SO4 acts as a binder in tailing pelletizing, is recommended. Keywords: Cu-Ni ore dressing tailings, granulated slag, heap leaching 1. INTRODUCTION From the accumulated on the territory of Russia wastes three quarters fall to the mining industries. For producing of a ton of metal it is formed from 30 up to 100 tons of tails of benefication. For their removal and storage it is spent from five to eight percents of the costs of produced metals.
    [Show full text]
  • In Situ Resource Recovery from Waste Repositories: Exploring the Potential for Mobilization and Capture of Metals from Anthropogenic Ores
    J. Sustain. Metall. DOI 10.1007/s40831-016-0102-4 RESEARCH ARTICLE In Situ Resource Recovery from Waste Repositories: Exploring the Potential for Mobilization and Capture of Metals from Anthropogenic Ores 1 1 1 Devin Sapsford • Peter Cleall • Michael Harbottle Ó The Author(s) 2016. This article is published with open access at Springerlink.com Abstract Wastes and the waste repositories in which they Introduction reside are becoming targets for resource recovery, both for legacy wastes and for future waste arisings as part of a Waste repositories can be considered the ore deposits of the desire to move toward a circular economy. There is an ‘anthropocene.’ Having historically disposed of vast urgent requirement to explore concepts for practicable quantities of industrial, municipal, metallurgical, and technologies that can be applied to these ends. This paper mining waste into or onto the ground, societies have put presents a synthesis of concepts concerning in situ tech- into geological storage an enormous quantity of resource in nologies (developed from mining and contaminated land a range of materials of value such as metals and energy (in remediation industries) that have enormous potential for the form of biomass and polymers). Therefore, instead of application to technospheric mining. Furthermore, poten- considering these waste repositories to be a legacy waste tial target waste streams and their mineralogy and character issue and a long-term liability, a paradigm shift is required are presented along with a discussion concerning lixiviant to view these installations as ‘resource hubs’ for future and metal capture systems that could be applied. Issues of recovery.
    [Show full text]