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By B. Adams, T. Angelov, G. Sasov, D. Steinhilber, A. L. Tsekov, S. Neufeind

A complementary ion exchange/solvent extraction process for the recovery of copper from low- grade ores is described. It has successfully been implemented on a full-scale plant level at the Buchim Copper Mine in Macedonia, yielding a maximum copper cathode production of 2400 tons per year. Compared with conventional SX/EW operations, this technology makes the exploitation of low-grade copper ores economically attractive, due to reduced operational and capital expenditures. Furthermore, the additional Lewatit® ion-exchange installations diminish the volumes of harmful organic substances in the following SX step and minimise the risks associated with the handling and usage of these chemicals, such as environmental pollution or fires. Finally, the significantly diminished quantities of liquids for the SX operation have a tremendous effect on the footprint of the plant (ca. 50% less) thereby leading to a reduction of capital expenditures. This paper reviews the main stages of the combined IX/SX process, the applications for metal recovery and introduces projects where the process is applied. Key findings of the process are also presented. A comprehensive technical comparison between processes has been carried out. This paper also evaluates the advantages of using combined IX/SX technology as a purification and separation step in copper production process, with the aim of further increasing the overall copper recovery and to ensure that a suitable copper concentration in the advanced electrolyte is achieved. The implementation of a Ion Exchange (IX) process in the classic Solvent Extraction-Electrowinning process(SX/EW) is found to be beneficial for processing of pregnant leach solutions both from spent and new copper heaps and dumps, acid mine drainage and other industrial streams without any preconditioning as well as in terms of achieving improved recoveries and copper cathode quality. INTRODUCTION The concentration and separation of copper from primary leachates is one of the key operations in the hydrometallurgical processing of oxide ores (Langner, 2011). Conventionally, this basic operation is conducted by submitting the pregnant leach solution (PLS), with a 1–5 g/L Cu content, from the initial sulfuric acid leach to a solvent-extraction (SX) process in which copper reports to the organic phase. After phase separation, the metal is stripped from the extractant/diluent mixture employing sulfuric acid to furnish a concentrated metal solution, usually containing 40–50 g Cu/L. The final products of the overall process are copper cathodes, which are obtained from a terminal electrowinning step.

Jan 1, 2019

By Roger C. Parsons

"The problems presented by ice formation and interference with processes, structures and mechanical operations in the mining industry can be expected to increase sharply as more of our mineraI needs are supplied from the far north. A process of rapid ice destruction is presented which lends itself to the effective removal or penetration of ice. Suggestions are offered for applying the system to problems related to mining activity in cold environments. The system can be readily adapted to large-scale operation, the reactant components being transported in crystalline form and volatilized on site.IntroductionThe number of operational mines in northern environments, relative to the number of mines in the temperate zone, will increase in the years ahead. This is not surprising, because:(a) in the past, those mines closest to centres of commerce had minimum transport charges and hence were more economic to develop;(b) great centres of commerce were far removed from northern environments;(c) the exhaustion of ores and lowering of grades in temperate zones now offset to some degree the extra transport costs applied to northern ores;(d) the abundance of excess energy in the north in the form of oil, gas and hydropower attracts mining as a means to justify its development; (e) assuming that the frequency of mineral occurrence north of the 52° N latitude is no different than south of it, there are many deposits waiting to be developed.As a result of current and projected activity in northern environments, we are faced today, and will be increasingly so in the future, with mining problems rarely encountered before-problems related to below-freezing temperatures. Engineering activity in permafrost regions will increase as new mining ventures are developed north of the 52° N latitude, roughly coinciding with the -1.1 ° C isotherm in Labrador, the upper temperature boundary for permafrost."

Jan 1, 1982

By AIME AIME

THE sixteenth annual meeting of the Woman's Aux¬iliary, A. I. M. E., was held Tuesday morning, Feb. 16, at the Engineering Societies Building. The meeting was well attended, there being 99 registered from the metropolitan area and 78 from the sections throughout the United States. Mrs. Sharpless, the secretary, read the minutes of the annual meeting held a year ago, after which Mrs. Bassett, the president, gave her address of welcome. Mrs. Bassett said in part: "I would like, at this time, to welcome you all to this, our sixteenth annual meeting, and to express my appreciation to all the national officers and members of the board of directors for their loyal support and for the excellent work done by the chairmen of sections and their members. It is with much pleasure that I look back upon my visits with the sections in Washington, Arizona, Northern and Southern California, Chicago, Colorado, Western Pennsylvania and Utah before I assumed the office of president. During the last year I have much enjoyed meeting with the sections in Boston, Washington and New York. It is our duty to see that the achievement for 1932 be equal to that of the year that has just passed."

Jan 1, 1932

MR. L. C. BALL, chief government geologist, Queensland, wrote: This paper is intended as a severely mechanical exposition of the means adopted to deal with tremendous inflows of water concurrently with development and exploitation; but incidentally it serves as a splendid exposition of close co-operation maintained between the geological and engineering branches of this large organization.I have been impressed by the completeness of the mine plans of 'Mount Isa Mines Ltd.; but only such a paper as this has brought fully to my understanding the difficulty and complexity of the solid geometry involved in the detection and plotting of the orebodies and their stratigraphic control, including faults and large-scale brecciations, and the managerial foresight that set going the initial investigations.The company's geological branch of course must be given full credit for the results attained, but it gives me pleasure that the Geological Survey of Queensland has been closely associated in much of the study.It is noted that complete drainage was affected, but it would be interesting to learn whether the brecciated zone will again become waterlogged and whether from above or from below, and whether there has been any change in the dissolved mineral content of the water as the work progressed.

Jan 1, 1939

The development of computers is examined in the context of the mining industry. The risk element is given as a reason for the slow introduction of the computer into mining. Dealing with mining's uncertainty is seen as a major role for computers. The use of computers is traced from early accounting applications to current involvement with all aspects of mining. The problems associated with increasing use of computers and their impact on management is discussed in depth. Disenchantment of management is thought to arise from unfulfilled expectations. Contributory causes are given as overselling of computers, reaction against change, speed and growth of computer technology. The solution is seen to lie in a more dominant role for user management in the development of computer systems and greater emphasis on education. The computer of the future will then become integral to the mining process as an extension of management's planning and control function.

Jan 1, 1974

By R. S. C. Rogers

A mathematical model is proposed as a general formulation for the analysis and simulation of once-through crushing machines. Methods are described which can be used to estimate parameters of the proposed model from experimental data, thus minimizing reliance on backcalculation. The applicability of the model is demonstrated in the analysis and simulation of laboratory and full scale double roll crushers, and with evidence given for a laboratory scale cone crusher. An extension of the model for closed circuit crushing is also described.

Jan 1, 1984

By F. Pošepný

Part I.—General Facts and Theories. PAGE 1. Systems of Classification Employed Hitherto, . . 199 2. Standpoint and View of the Present Paper, . . . 206 3. The Xenogenites in General, ...207 4. The Subterranean Water-Oirculation, . . . 212 A. The Vadose Underground Circulation, . . . 213 Filling of Open Spaces Formed by Vadose Circulation, . . 217 B. The Deep Underground Circulation, . 220 Ascending Waters Encountered in Mines, , 222 Related Phenomena near the Surface, . 225 Mineral Springs at the Surface,. . 230 Chemical Constitution of Mineral Waters, . 232 Minute Metallic Admixtures in Mineral Waters, . . . 238 Alterations Produced by Mineral Springs, . 240 Structural Features of the Deposits of Mineral Springs, . . 244 5. Origin of Ore-Deposits in the Deep Region, . . . 247 Manner of Filling of Open Spaces in General, . . . 254 Part II.—Examples or Classes of Deposits. 1. Ore-Deposits in Spaces of Discission, .. 264 General Features and Illustrations, a. Ore-Veins in Stratified Rocks, .. 269 Clausthal, 269; Andreasberg, 270. b. Ore-veins in the Neighborhood of Eruptive Masses, 271 The Erzgebirge, 271; Przibram, 272. c. Ore-Veins Wholly Within Large Eruptive Formations, 274 Hungary, 274; Dacian Gold-field. 275; Verespatak, 276; Vulkoj, 276 ; Comstock lode, 278.

Jan 1, 1894

MARSHAL Foch has been made an honorary member of the four national American societies of civil, mining and metallurgical, mechanical, and electrical engineers. The governing bodies of these societies, aggregating 45,000 members, conferred this signal honor in expression of the appreciation of American engineers for the unmatched services of this master of engineering principles. At Engineering Societies Building, in New York City, on Tuesday afternoon, Dec. 13, the presidents of the four societies presented one beautifully engrossed certificate of honorary membership in the four societies. The auditorium was filled so that not even standing room was left, more than a half hour before the cere-monies began, and the main entrance on the street had to be closed. J. Vipond Davies, president of the United Engineering Society, made the opening address. Col. William Barclay-Parsons, 'who was commander of the first engineer regiment to go abroad, addressed Marshal Foch in French. Colonel Parsons said: The art of engineering was defined a long time ago as "the art of directing the great sources of power in nature for the use and convenience of man." No better definition can be found today. Of all the sources of power in nature, the greatest, the most valuable, and at the same time the most difficult to direct, is the energy of man himself. He who can direct human energy and turn it to the service of mankind is a great engineer. You, Marshal, have directed a greater mass of human energy than any other man has ever done. And you have successfully directed this mass for the highest uses of mankind, in that you by its aid have preserved for him one of the most precious of human possessions-liberty-liberty not only for your own illustrious country, but for all the nations of the world. The four national engineering societies, of the United States now desire to make record of their appreciation of this fact and to convey to you an expression of their most profound admiration for the great leader of men by conferring on you honorary member-ship in all the societies, the highest honor in their gift and one hitherto never conferred on a single individual. Four thousand members of these societies were enrolled in the armed service of the United States, the greater part of whom had the glorious distinction to serve the common cause in France under your orders. They heard the voice and they saw the hand of the master as he led them through battle to victory. Now we desire that you will still continue to lead us, but in peace, by permitting us to inscribe your name at the head of our roll of honor, where it will be, as your deeds have been, an example to us to do better work, and where it will remain forever a noble inspiration for all future generations. Marshal, in the name of those members of the societies who served under your orders and particularly .in the name of those who fell on the field of honor in France, I salute you.

Jan 1, 1922

By Robert Craig, Earl L. Rau

Introduction Grinding circuits are used to reduce the particle size of ores to the size desired for beneficiation or to grind a concentrate to a size required for final marketing. Grinding and classification can be carried out using either wet or dry circuits. Most sulfide ores are ground in wet circuits using one or more stages of grinding to obtain the necessary mineral liberation to produce a final concentrate which will meet the desired criteria. Iron ores are ground in circuits applicable to the particular ore using either wet or dry grinding. Nonmetallic minerals frequently present different requirements. Barite is likely to be subjected to wet grinding before beneficiating the ore; the concentrate is dried and then dry ground to meet market particle size requirements. The one thing that most mill operators will agree to is that there is no such thing as the "best" configuration of equipment for grinding. The circuit which works well on one ore may be totally unsatisfactory for another ore body. The general trend in the industry is flow sheet simplication with fewer parallel circuits instead of multiple-line circuits using small mills. This change in philosophy has been brought about by the saving of both capital and operating costs that may be possible with larger equipment. Remember that comminution is basically a very inefficient process, and that the costs can range upwards to 50% of the total milling costs. It, therefore, behooves the mill operator to carefully design his grinding and classification circuits. He must ascertain the optimal economic particle size for beneficiation and then make certain he has achieved the best balance between capital and operating costs to achieve the desired mesh of grind. Equipment Grinding circuits consist of one or more pieces of equipment to grind the solids. Generally, these circuits include one or more grinding mills, classification equipment, and the necessary materials handling equipment such as pumps, pipelines, and conveyors. There are many different types of equipment available which are used to grind and classify ores and minerals. Following is a tabulation of most of the equipment used for wet and/or dry grinding.

Jan 1, 1982

By J. Larsen-Badse

The resistance to dry sliding abrasion us been measured for some hardened and tempered carbon steels. The wear resistance, defined as the reciprocal of the volume loss per unit sliding distance, is found to vary linearly with the hardness of the abraded surface. The data fit two lines, one, of high slope, for the pure metals and for the annealed steels and another, of smaller slope, for the hardened and tempered carbon steels. A relationship is developed showing the alwasion resistance to be proportional to the hardness of the material and to en, where n is the exponent of work hardening. The values of n and of the hardness FOR most materials a high resistance to abrasion is generally associated with a high value of indentation hardness. Brine11 even used the abrasion resistance as a measure of hardness in an attempt at expanding the hardness range covered by his indentation-hardness test.' When comparing different types of materials there is, however, only a very general relation between abrasion resistance and hardness. Sample brittleness seems to contribute to the deviation from a direct relationship. In general, increased brittle- are those relating to the heavily deformed abraded surface. However, for materials having n constant or varying m a regular manner over a wide range of strailts, the wear resistance will also be a linear function of the bulk hardness of the material. For tempered steels containing a dispersion of cementite in ferrite the increase in wear resistance due to the dispersion is found to be a linear function of the volume fraction of Fe3C and of the reciprocal of the mean free ferrite path. This indicates indirectly that the yielding of this material, when it is already heavily deformed, follows the Orowan criterion. ness leads to decreased abrasion resistance.' When comparing materials in the same group, e.g., the metals, the spread is less. Kruschov found that the abrasion resistance of pure metals and of annealed steels is directly proportional to the hardness of the metal. For hardened and tempered steels he obtained another linear relationship, one of smaller slope and intersecting the line for the pure metals at the location of the data for the annealed steels. He also found that the abrasion resistance of cold-worked metals is independent of the degree of cold working. This shows, as he concluded, that the process of abrasion work hardens the metal in the surface region to a very high degree.

Jan 1, 1967

By R. Y. Wan

Thiocyanate was evaluated for gold recovery from low-grade refractory gold ores following biooxidation for an acidic heap leaching approach. One of the important features in using thiocyanate is that the leaching can be performed in acidic media, thus avoiding problems related to neutralization and material handling as leaching with alkaline cyanide. Also, the acidic leaching enables the use of ferric ion or bioleach solution as oxidants. In this study, Newmont-Nevada low-grade refractory sulfidic ore was biooxidized in columns at a particle size of 100% passing 102 mm. Thiocyanate leach on the biooxidized ore sample was performed on both ground samples in pulps and coarse material in columns using ferric ion as an oxidant. The variables of thiocyanate and ferric ion concentrations were compared for effect on leaching. Thiocyanate leach results are encouraging and indicate potential for development of a practical process. Gold extractions by thiocyanate are comparable to cyanide leach. Thiocyanate consumption was higher than cyanide, but was in an acceptable level.

Jan 1, 2003

By T. M. Barton, M. Gauna, A. A. Campoli

Coal mine bumps, the violent failures of overstressed coal, present a safety hazard to miners when longwall mining is conducted in deep, bump-prone coal mines. Two different longwall gate entry systems were evaluated in a southern Appalachian coal mine located in the Pocahontas No. 3 coalbed under approximately 610 m (2000 ft) of overburden that included a massive sandstone member. Both gate entry systems employed a center abutment pillar flanked by yield pillars. The original design used a 24.4-m (80 ft) square abutment pillar, while the new design employed a 36.6-m x 54.9-m (120 ft x 180 ft) abutment pillar. Rock mechanics instrumentation data analysis and in-mine observations indicated that this increase in abutment pillar size significantly decreased bump potential. The new design in worst-case conditions increased effective bearing area 62%, with only a 9% increase in gate entry system width, and eliminated face bumps that were experienced with the original gate entry design.

Jan 1, 1993

By J. A. Dlas Lima

Alunorte is a metallurgical-grade alumina refinery located in northern Brazil. This plant which was designed to produce 1.1 million mtpy of calcined alumina, started operation in July 1995. A process information system was installed before refinery start-up. It has been a main factor in process improvements, which resulted in an increase in production from 1.1 to 1.5 million mtpy. This system has been particularly useful for analyzing data and allowing retrieval of data by process engineers. This paper describes how a quality monitoring system to evaluate all aspects and stages of production, as well as alumina silo level and blending percentage, was developed. This system was designed to give support to ISO 9002 certification, which happened in December 1998. The quality monitoring system was developed using Microsoft Excel 7.0 and makes extensive use of VBA macro. The primary users of the system are shift foremen, managers and engineers, who use it to track the process and avoid variations in alumina quality.

Jan 1, 2000

By B. A. Rogers

ACCORDING to petrographic investigations, 1-4 cooled steel furnace slags contain a number of substances that have been shown to be ferro-magnetic5,6 and hence capable of undergoing appreciable changes of susceptibility with temperature. Since any alteration of the suscepti-bility of a constituent affects the average susceptibility of the sample, information concerning the nature of the substance should be deducible from its magnetic behavior. The possibility of obtaining information concerning slags in this way led to the construction of the apparatus to be described. FUNDAMENTAL PRINCIPLES OF APPARATUS The most convenient method of observing changes in mass suscepti-bility? with temperature is the one employed by Curie7 in his original investigation of the changes in magnetic properties of substances at elevated temperatures. As the method has been described frequently in the literature and in textbooks, only a brief review of the fundamental principles need be given here, but the particular arrangements used in the present work require a more detailed description.

Jan 1, 1939

The magnesite deposits near Young, N.S.W., occur in decomposed serpentine rock below a soil. and alluvial cover. They show considerable variation in both quality and depth which greatly hampers mining operations. Seismic refraction techniques afford methods of conducting detailed and reconnaissance surveys which yield a depth and velocity analysis of the serpentine/magnesite refractor. The measured seismic velocities may be used as an index of the presence and quality of the deposits. The Seismic Timer which was used in the test surveys is a simplified seismograph which makes use of seismic reciprocity by replacing the conventional seismic shotpoints with geophone stations and the conventional geophone stations with impact points of a sledge hammer. Thi,s enables the use of detailed seismic refraction techniques which yield the depth and velocity analysis of the refractor.INTRODUCTIONThe magnesite deposits near Young, N.S.W., were produced by a process of leaching and enrichment of magnesium in serpentine rock. The magnesite occurs in nodular form emplaced in decomposed rock at shallow depths below soil and alluvium. The depth ranges from close to the surface down to some tens of feet. The deposits are patchy and show considerable variation in both quality and depth, giving riseto considerable difficulties in mining operations.Due to the thorough leaching of the surface material, geochemical tests carried out so far have not proved satisfactory for locating the pockets of magnesite enrichment.It was decided to test the application of detailed shallow seismic refraction methods to the investigation of both the depth and quality of the deposits. The tests were carried out...

Jan 1, 1962

By L. C. McCabe

THE object of the present investigation was to discover a physical basis for rank differentiation of coals, particularly the coals of the Illinois basin. Vitrain1 was selected as the most appropriate coal material to use in the investigation, because of its homogeneity and ease of acquisition and handling. Previous Investigations.-Hoffman and Jenker2 have shown that their index of reflection is a characteristic of coal rank and that the Leitz slit microphotometer may he used in determining the different intensities of reflection. Zhemchuzhnikov3 measured the luster of several Russian coals with a color analyzer and found that the degree of luster was indic-ative of rank. Luster-volatile matter curves based on data from Sucan and Donetz coals were satisfactorily used for determining the rank or volatile content of other coals after the luster strength was determined. In 1934 Fisher4 reported refractive indices of 1.76 for bituminous vitrain and 1.87 for semibituminous vitrain. Investigation of Angle of Polarization.-Early in the present investiga-tion several determinations of the refractive indices of the vitrains were made by immersing the minus 150 plus 200-mesh powder in oils. It was found that all the samples fell within the range 1.6 to 1.8. However, difficulty was encountered in securing oils in this high index range that were closely enough spaced to separate some of the coals. The writers made a number of determinations of the angle of maxi-mum polarization from the polished surfaces of the vitrains and derived their refractive indices by the procedure described in the follow-ing paragraphs.

Jan 1, 1937

By S. Ostap

INTRODUCTION Paradoxically, it has been found that the people who are the most aware of the origin, mineralogy and composition of bauxite are also the people who are the least aware of how bauxite composition affects its treatment by the Bayer process. These people are the exploration and mining geologists normally associated with aluminum producing companies. The purpose of this paper is to give some idea of how the concentration and physical nature of the different minerals found in bauxites affect the operation of the Bayer process used to extract their alumina content. The bauxites we will consider here will be only the tropical bauxites such as occurring in Jamaica, various countries in South America i.e. Guyana, Surinam, Brazil, African bauxites, Malaysia and in Australia. When we speak of the Bayer process, it will be the North American version of the Bayer process using low caustic concentrations and bauxite digestion temperatures varying between 130° to 250°C. TABLE 1 shows the minerals and elements of interest occurring in tropical bauxites. The minerals and elements listed in the table do not by any means represent all of those identified in bauxites. Using mass spectrographic analysis on six bauxites from different geographic locations, we managed to identify between 50-60 different elements. Fortunately, only about 13-14 of these elements possess the necessary chemical properties to be able to accumulate in caustic Bayer solutions. The remainder are either not attacked, or form insoluble reaction products with some main liquor component, i.e., hydroxide, aluminate or carbonate, or reprecipitate with alumina trihydrate during the precipitation stage.

Jan 1, 1984

Page Fundamental Principles Involved in Segregation in Alloy Castings. By R. M. Brick. (With discussion)............................* Review of Factors Underlying Segregation in Steel Ingots. By B. M. LarseX.. (With discussion)............................. 4x4 Introduction to the Session on Segregation in Steel. By Earle C. Smith......436 Relation of Open-hearth Practice to Segregation in Rimmed Steel. By J. W. HaLley and G. L. Plimpton, Jr. (With discussion)................438 Segregation in a Large Alloy-steel Ingot. By S. W. Poole and J. .4. Rosa. (With discussion) .............................459

Jan 1, 1945

By H Indirawati, R Ayres, A Nur Kasnanto, S Konopa

As a project moves through the mine life cycle, the quantity of data available increases and the understanding of the orebody matures. Incorporating new information quickly and efficiently in current 3D models, is essential for adding value across the life-of-mine value chain. At the Martabe Gold Mine, the resource development group manages 14 drill rigs on six resource projects, including three operating mines. The Martabe deposits are geologically complex and the volume of new information that becomes available each day is substantial. It is imperative that new geological and assay information is integrated into the 3D models as soon as possible, so that drill planning and targeting can be modified accordingly. Martabe uses Leapfrog<sup>®</sup> 3D software to update and interrogate the 3D models on a dynamic basis as data becomes available. This results in faster and more effective changes to drill planning and schedules. The impact of this is better drill productivity and cost savings due to optimal drill targeting, and availability of up-to-date models incorporating the most current data. CITATION: Konopa, S, Ayres, R, Nur Kasnanto, A and Indirawati, H, 2018. Optimised drill targeting using dynamic 3D modelling, Martabe Gold Mine, Indonesia, in Proceedings Complex Orebodies Conference 2018, pp 99–101 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

The American Petroleum Institute, 250 Park Ave., New York, N. Y. Lacey Walker, Secretary. A complete price list of publications will be sent upon application. The American Petroleum Institute issues a variety of publications; in addition to the Daily Oil Digest ($25 per year) and a weekly Statistical Bulletin ($12.50 per year to nonmembers), a Quarterly is published ($4 per year to nonmembers). Books published by the Institute: American petroleum supply and demand, $3; A series of "Petroleum facts and figures" for each of the years 1928, 1929, 1930 and 1931, $2 for each copy; Function of natural gas in the production of oil, $1; Bibliography of organic sulphur compounds, $4; and "Oil" (Oil Industry Series in one volume), 50 cents per copy. Volumes of the first six annual Meeting Proceedings are out of print, but the Proceedings for the 7th annual meeting in 1926

Jan 1, 1933