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By Gonzalo Bernstein, David G. Meadows, German Naranjo, Edgardo Tapia

"During the last decade Antofagasta Minerals’ Los Pelambres Mine has dramatically increased its ore throughput following the fast initial phase ramp up through a series of planned incremental expansions. The original 85,000 mtpd, two SAG line plant was commissioned in 1999 and rapidly exceeded nameplate tonnage in only a few months. Following this, the inclusion of a pebble crushing circuit resulted in throughputs in excess of 114,000 mtpd and a recent, final third line SAG and ball mill addition have taken the plant to over 175,000 mtpd even with increasing ore hardness and changing ore feed characteristics. The progressive changes are described in this paper together with how the technical challenges have been met.INTRODUCTIONMinera Los Pelambres is a world class copper-molybdenum operation located in the Salamanca area in Chile, in region four, approximately 500 km north east of Santiago, the capital of Chile. In the late 1990s Antofagasta Minerals developed the Minera Los Pelambres project in Chile at an investment cost of approximately $1.3 billion USDs. The project construction was successfully led and completed by Bechtel Corporation in 1999 and within a matter of months the plant was already exceeding the nameplate capacity of 85,000 mtpd. In 2001 a pebble crushing circuit was added to raise the capacity to 114,000 mtpd. In the early part of 2003-2004, it was recognized that the hardness profile was changing with depth and that in order to maintain the plant capacity additional power would be needed in the SAG mills together with upgrading of the primary crusher. In conjunction with these changes a fifth ball mill and a second primary crusher station would also need to be installed. A further detailed engineering study and evaluation was initiated by Minera Los Pelambres. This was lead by Bechtel Corporation with major design contributions from FLSmidth and Siemens in order to establish the re-powering requirements for the SAG mills. These re-powering changes together with the inclusion of a pebble crushing circuit took the plant to up to 125,000 mtpd even with harder more competent ores. Finally in the last two years an additional grinding line has been added to take the capacity to consistently over 175,000 mtpd. The third line was installed in a record time of 256 days. A schematic of the current comminution circuit, discussed in this paper, is shown in Figure 2."

Jan 1, 2012

By Jacque Turgeon, Gontran Foy

"The Mineral Research Centre of the Quebec Department of Energy and Resources has worked extensively on the development of a dry process to extract pure mica flakes from a phlogopite ore. The liberation of mica from the gangue is effected basically by impact crushing, and the ground ore is screened into several fractions, each having a fairly narrow range of grain size. Each sized fraction is then fed to an air separator where heavy grains are separated from light flaky grains. Heavy fractions are returned to hammer mills where gangue minerals are ground finer and blocky mica particles are exfoliated. A second stage of screening is performed and each fraction is sent to an air separator. This sequence is repeated until mica products are virtually free of gangue. These different fractions are then treated in a cage mill in which mica flakes undergo a more orderly exfoliation along cleavage planes. The ground mica is again submitted to a final screening stage, after which each fraction constitutes a final commercial product.This process permits the recovery of about 70% of the mica contained in the ore. The over-all process will be described along with technical details of each unit operation. Recent work on a wet grinding method to produce very fine mica will also be discussed.IntroductionRecords of production of mica in Quebec date back to 1886. Production has been more or less continuous since that time, with peak activity during the war years. Production was interrupted in 1966, but started again in 1972 when Marietta Resources and Laviolette Mining and Metallurgical Corporation started their joint operation in Canton Suzor, northwestern Quebec. Mica deposits of more or less importance exist in different parts of Quebec, of which three have attracted attention in recent years: the Canton Suzor deposit, the Canton Lamy deposit and the Canton Chasseur deposit. The Suzor orebody was first identified by Carl Faesler in 1936, who described the rock as ""brown biotite in flakes half an inch in diameter, with interstitial augite, apatite and feldspar""."

Jan 1, 1982

By A. Dave Mackintosh

The Current demand for potash has pushed world prices to record levels and allowed Saskatchewan producers to operate at maximum capacity. Several years of strong demand has resulted in a permitting rush not seen since the 1960?s. Even though Saskatchewan has a huge potash resource, mining and processing constraints will limit the areas of economic development. Introduction In 1969 M. E. Holter prepared a report ?The Middle Devonian Prairie Evaporite of Saskatchewan?, published by the then Dept. of Mineral Resources. Holter?s report has remained the bible of geologists working in potash ever since. It is astounding that a report written before there was really much potash mining history in the province, is as valid today as when it was first published. This paper re-iterates much of Holter?s report and adds a little mining experience to essentially confirm the importance of his work.

May 1, 2008

By S. S. Burns

"AbstractShovels of 18 cubic yard capacity and larger are described which incorporate advanced technology and techniques providing performance and operation tailored to meet the needs of open-pit mining.To achieve the goal s of increased production at lower cost with consideration of maximum availability, lower energy consumption per ton and low •impact on pit power, Harnischfeger Corporation developed a solid -state drive system (""Electrotorque"" - P&H trademark) and applied unique transmission methods.To date, more than 250,000 hours of experience in different parts of the world under varying operating and environmental conditions has proven that the ""Electrotorque"" shovel is the shovel of the future, today.This paper will discuss the electrical features and touch briefly on some mechanical features.Introduction to ""Electrotorque""THE hoist, crowd, propel and swing machinery of an electric mining shovel are driven by direct-current motors.A D.C. motor is used instead of an A.C. motor because the torque output per ampere input is at a maximum and the fact that it is doubly-fed (armature and field ) provides optimum flexibility in control.The power that is available in the pit is alternating current power. It is therefore necessary to change or convert this A.C. power to D.C. power so that the D.C. motors can be used."

Jan 1, 1977

By M. W. Grabinsky, P. B. Tomory, J. Carvalho, J. H. Curran

Many underground mining operations use Split Set friction stabilizer bolts for rock support. Currently, however, little has been done to quantify the effects of various rock mechanics and operational parameters on the capacity of frictional support systems. The strength of Split Sets is usually measured by means of a pull test wherein a jacking force is applied to the bolt and a slip load is obtained. In order to evolve a rational design procedure for this type of support, an extensive database of over 900 pull test results from more than 50 mines through- out North America has been assembled and analyzed. Associated relevant rock mechanics parameters (rock type and quality) and operational details (drilling method, bit size, drive time, time to pull test) were also obtained, as completely as possible, for each test. Analysis of the information has yielded several charts that relate pull-out strength to relevant parameters and simple statistical analyses were conducted where necessary. Quantified distributions for pull-out strength were also produced for several operating conditions. The factors that most significantly affect bolt strength have been identified and specific applications to design are discussed. The information presented will assist mining engineers in designing safer and more economic support using Split Sets.

Jan 1, 1998

By E. Topuz, C. Duan

"INTRODUCTIONOperations research (OR) applications have experienced a substantial growth within the mining industry during the last three decades. The purpose of this paper is to present a summary of the results of a comprehensive survey of the application of various OR techniques to the major mining activities. It is hoped. through this sur vey , that the most widely used OR approaches, the important areas of application, and future trends have been identified.This survey included more than 500 articles published in this field in English since the late 1950s. Most of the relevant literature was found in mining publications, but, in terms of quality and originality, important applications were also found in literature not related to the mining industry. The sources constituted periodicals, proceedings research reports, and a few books. A listing of selected publications from which three or more articles reviewed in this survey appear is given at the end. Operations Research MethodologiesOperations research is concerned with optimal decision making in, and modeling of, deterministic and probabilistic systems that originate in real-life situation s. One basic feature of the OR methodologies is the attempt to optimize certain design parameters, subject to a set of constraints. This distinction has been employed in the survey as a guideline for selection of the techniques covered under the title "" OR methodologies"". The methodologies thus encountered in the literature are listed below. In a few cases, simulation has not been considered because it is not an optimization method per se."

Jan 1, 1989

By Mehmet F. Taner

"Abstract - The East Sullivan Stock (ESS) is a small, composite felsic alkaline pluton of presumed late Archean age in the Val d’Or mining district. Three main facies have been distinguished: monzonite sensu stricto, porphyritic monzonite, and green trachytic porphyry. This monzonitic group of rocks is of relatively homogeneous composition with high abundances of Na2O, K2O, Ba, Sr, Rb, Zr, Mo and LREE. The alkaline ESS is distinguished from other igneous units in the Val d’Or mining district, such as the Bourlamaque Batholith, by relatively high concentrations of Ba, Sr, Rb, Mo, Cu and Au. The ESS hosts many base (Cu, Mo) and precious (Au) metal occurrences, including: (1) porphyry style Cu-Au-Mo disseminated sulfide deposits, (2) Cu-Au deposits in volcanic rocks near the ESS contact, and (3) pyritic gold mineralization in east-west trending shear zones. The ESS is well defined by concentrical zoning on the aeromagnetic vertical gradient color map, and displays four linear trends, which are assumed to be structural lineaments, at 035°-055°, 320°-300°, eastwest, and north-south. The main mineral occurrences related to the stock display a preferred spatial association with the east-west linear magnetic trends.The ESS is preferentially located along a major structure and was emplaced late in the evolution of the Abitibi subprovince like other felsic alkaline plutons. This stock is similar to late-tectonic mineralized felsic alkaline intrusions of the Kirkland Lake and Larder Lake mining districts in Ontario, and to the Allard stock in the U.S.A. which is associated with gold and base metal mineralization. Similarities also exist with younger alkaline plutons associated with Cu-Mo-Au porphyry deposits in the Canadian Cordillera, which formed in tensional tectonic environments. The felsic alkaline magma may have formed by partial melting of deeply buried supracrustal rocks, concomitant with the development of deep fractures such as the Cadillac Fault. In such an environment, hydrothermal solutions carrying remobilized metals from deep supracrustal rocks may have deposited gold and base metals in structural traps. Plutons similar to the ESS should be good targets for mineral exploration. Résumé - Le Stock de East Sullivan (SES) est une intrusion composite alcaline d’âge tardiarchéen, situé dans le camp minier de Val d’Or. Trois principaux faciès ont été identifiés: une monzonite sensu stricto, une monzonite porphyrique et un porphyre trachytique vert. Les données chimiques montrent que ce groupe des roches monzonitiques est relativement homogène en composition avec des concentrations élevées de Na2O, K2O, Ba, Sr, Rb, Zr, Mo et ETRL, définissant une suite alcaline typique. Cet alkalin stock peut être facilement distingué des autres unités géologiques de la région de Val d’Or, tel le batholite de Bourlamaque, par une concentration élevée de Ba, Sr, Rb, Mo, Cu et d’Au. Le SES contient plusieurs importants prospects de métal précieux (Au) et de métaux de base (Cu, Mo), incluant: (1) une minéralisation disséminée de type porphyre Cu-Mo-Au, (2) une minéralisation de Cu-Au dans les roches volcaniques encaissantes hôtesses près du contact et (3) une minéralisation d’or pyritique dans une zone de cisaillement de direction est-nordest. Le SES est bien défini sur la carte aéromagnétique en couleurs du gradient vertical par des zonages concentriques, où quatre linéaments structuraux ont été reconnus: 035°-55°, 320°-300°, est-ouest, et nord-sud. Les principales zones minéralisées spatialement associées au stock sont généralement situées soit près des linéaments magnétiques est-ouest, soit le long de ceux-ci.Le SES semble s’être mis en place le long d’une structure majeure, développée tardivement dans l’évolution de la Sous-province abitibienne, comme les autres plutons alcalins felsiques. Ce stock est similaire à la suite tardi-tectonique d’intrusions alcalines minéralisées des camps miniers de Kirkland Lake et de Larder Lake en Ontario, ou"

Jan 1, 1996

By D. N. Thurston

Luscar Stereo commenced construction of the mine at Coal Valley, Alberta, in August, 1976. It is designed to produce approximately 2.5 million clean short tons of steam coal annually - 2.0 million tons per year being committed to Ontario Hydro and 0.5 million tons per year being committed to Neptune Terminals for sale on the export market. The project involves constructing a heavy-media coal preparation plant, erecting a 42-cubic-yard dragline, constructing a shop/office complex, and developing three surface mining zones and associated facilities. As there were no existing facilities in the Coal Valley area, it was necessary to establish access roads, an airstrip, temporary utilities, fuel supplies, a construction camp, rail upgrading and communication services.

Jan 1, 1978

By V. Concha, M. Hashemzadeh

"The objective of this study was to gain a better insight into the kinetics of chalcocite leaching in an acidic ferric sulfate media. Chalcocite leaching in acidic media is known to occur in two sequential stages, with the first stage being much faster than the second. The leaching residue from the first stage is typically assumed to be a covellite type of material. This study hypothesized that the mineralogy after the first-stage leaching varies in response to different leaching conditions. We investigated the dependency of the mineralogy of the first-stage leaching residue on temperature and initial ferric concentration. The experimental results showed that chalcocite leaching behavior altered upon temperature and initial ferric concentration. A proposed combined reaction model was found to be able to describe the experimental data. The first stage was described very well by the shrinking core diffusion model while the second stage was described very well by the shrinking core chemical reaction model. This finding has important implications for mine operations to manipulate leaching conditions to create the desirable leaching kinetics.INTRODUCTION The kinetics of chalcocite leaching in sulfate media has been extensively studied (Cheng & Lawson, 1991; Fisher, 1994; Fisher, Flores, & Henderson, 1992; Niu, Ruan, Tan, Jia, & Sun, 2015). Sullivan (John D. Sullivan, 1930) proposed a two-stage process for chalcocite leaching in an acidified ferric sulphate solution. The two-stage leaching of chalcocite is presented as the following reactions:"

Jan 1, 2017

By T. G. Joseph

ABSTRACT: The Canadian oil sands provide some of the harshest mining conditions in the world. Asoperations demand ever bigger tools, the toll on large mobile mining equipment is high, with structurallife often half of that expected. Soft ground conditions predominantly lead to fatigue failure scenarios, poor stability, and inconsistent payload evaluations. These challenges are not solely a concern for Canadian oil sands mines; there are far-reaching implications for surface mining equipment in any poor ground-operating environment. This paper focuses on the basics of payload evaluation, motion response and a simple estimate of structural life for haulers.

Jan 1, 2011

By G. M. Behrend

"The mining and processing of mineral ores is a very old industry which is steeped in tradition. Rising demand for metals has recently forced the exploitation of lower-grade orebodies which require extensive beneficiation. The high capital expenditures involved, together with market pressures for high-quality concentrates and pellets, have forced the development of new process technologies which are heavily dependent on automatic process control. Development of suitable instrumentation has been rapid and it is being applied to mining processes today with a high degree of sophistication. The drive for higher efficiency and profitability goes on and has reached a level at which modern digital computers appear to be the only answer. However, the efficient application of a digital process computer is extremely complicated and is therefore approached by the mining industry with considerable hesitation.Some of the benefits promised by the digital computer can be obtained today by other means, which are more manageable and can provide immediate payoff. The result would be a building-block system which would utilize the digital process computer as its final component, to perform true plant optimization, free from routine chores."

Jan 1, 1971

By C. J. Cajka

Commodity agreements, trade liberalization, producer cartels, the New International Economic Order, price stabilization and access to supply are buzz words of the day. The international concern and dialogue on these concepts, often by a new breed of politically motivated experts, have generated intense interest in seeking an international solution to natural resource problems. While this momentum was maintained during the past year, the growing incidence of protectionist actions by several major nations has been eroding confidence in the global approach. The seriousness of current difficulties has created an urgent need for decisive action. At the same time, the limitations of the global approach have become more evident.

Jan 1, 1978

By Masashige Makifuchi, Hiroki Kumakura, Kota Nagai, Takahiro Kikuchi

"A large amount of platinum group metals (PGM) are used in automobile catalyst. It is important to recover the metals from wasted catalyst. Nomura and Kageyama (2013) suggested recovery process that PGM oxides were absorbed to perovskite-type oxide based on LaScO3. In their process, the PGM in wasted catalyst as absorbed to the perovskite-type oxide as PGM oxide. It has potential to each element in the process if the perovskite-type oxide is selected properly. In this study, the PGM oxide absorption properties of various perovskite-type oxides are investigated to develop a new recovery and separation process. The various perovskite-type oxide were synthesized with metallic platinum, palladium, rhodium at high temperature in air atmosphere. And the PGM contents in the perovskite-type oxide after the experiment are determined by chemical analysis. Some of them have the properties to absorb specific PGM oxide selectively. In addition, in order to increase the amount of absorption of PGM oxide and composition of the perovskite-type oxide experimental temperature was investigated. Then it is also found that doping another specific element to the perovskite-type oxide is effective to increase the amount of absorption of PGM oxide. Then a new recovery process of PGM from wasted automobile catalyst, in which PGM can be separate to each element, was designed.INTRODUCTIONA large amount of Platinum (Pt), Palladium (Pd), and Rhodium (Rh) are used in automobile catalysis (Figure 1) (Platinum, 2013). Natural supplies for these metals are limited and PGM mining can detrimental environmental impact. Therefore, the recycling of PGMs from wasted automobile catalysis is very important. The Rose process (Figure 2) was developed as a process to recover PGM from wasted automobile catalysis. In this process, the automobile catalysis is first crushed mechanically, and then extracting agent, copper (Cu), and flux are melted at high temperature. The mixture separates into a metal phase, (Cu alloy containing PGM) and slag. The PGM is enriched by oxidizing. Cu to Cu oxide. The PGM are then recovered and separated to each element in a wet process. However, it is hard to dissolve the PGM with acid because they are chemically stable and strong oxidation agent such as aqua regia is used. Moreover, to separate the PGM to each individual element, a solvent extraction process is required."

Jan 1, 2016

In the leaching and recovery of gold from copper containing gold ores using cyanidation, some copper minerals also dissolve which can have a detrimental effect on the process efficiency and economics. There are also environmental concerns with current operations discharging cyanide and copper cyanide species into tailings dams, and strict regulations prohibit this for greenfield plants. Cyanide destruction however is not an economic option for new plants treating copper-gold ores. This paper evaluates a potential recovery process to overcome the copper cyanide problem. Despite gold dissolution occurring in copper cyanide solutions having no free cyanide, gold recovery from ores is lower compared to free cyanide. Thus, cyanide addition has to be optimised to maximise the gold recovery whilst endeavouring to eliminate free cyanide at the completion of leaching (CN:Cu less than 3:1). Subsequently, copper cyanide can be recovered using activated carbon. The loaded copper cyanide is easily recovered from the carbon with a cyanide soak and distilled water wash such that the eluted CN :Cu ratio is less than 4:1. The copper could be recovered efficiently by electrowinning, by decreasing the pH of the eluant to 5. The remaining cyanide solution, after electrowinning, is then neutralised to form NaCN and recycled.

Jan 1, 2005

By Alessandro Navarra, Kristian Waters

Mineral concentrators are designed from preliminary geological data, and are therefore subject to geological uncertainty. This uncertainty has a demonstrable impact on the mining lifecycle, and has motivated stochastic strategic mine planning algorithms. The current paper describes how these algorithms may be extended to consider mineral processing operations in conjunction with open-pit mining operations. In particular, the paper describes an effective way to incorporate variable concentrator feed grade into these algorithms, which is the first step toward more elaborate representations of mineral concentrators. The resulting framework will be able to connect geological data to alternate configurations of the downstream resources, hence comparing the benefit of each configuration, and the corresponding capital investments. Sample computations are presented, comparing the NPV and utilization for several different mineral processing capacities.

Jan 1, 2015

By J. B. Watts

"THE Mine Engineering Department at Gaspe Copper is staffed by a chief engineer, assist-ant engineer, research engineer, chief surveyor, four instrument men, chief bonus clerk, draftsman, and a helper pool of four permanent men plus one or two students in the summer. The men are grouped according to function for organization purposes. Routine services provided by the Mine Engineering Department in-elude ail surface and underground surveying and mapping, preparation of working drawings, compilation of engineering reports, recommendations on ventilation, testing the mine air for carbon monoxide, research on mine equipment and its use, and the calculation of incentive bonus. Demand jobs from departments other than the Mine Department .are done on request. Such jobs may be in the plantsite, the Town of Murdochville, or at the shipping points at Gaspe harbour or the St. Lawrence river."

Jan 1, 1959

By J. Zhang, T. Oleniuk

It is well-known that Saskatchewan has the world’s richest uranium deposits and advanced processing technologies. Unlike the Saskatchewan deposits, complicated mineralogy is common for other places in the world. Mineralogy dictates the process. Mineral Processing at the Saskatchewan Research Council has been working with the uranium industry worldwide since its inception to develop effective processing technologies to suit the unique mineralogy of each deposit. This paper reviews the research and development of uranium processing technologies in the current major uranium production areas such as Canada, as well as the potential development regions like Argentina and Sweden. Acidic and alkaline leaching processes, as well as by-product recovery technologies are discussed based on mineralogy.

Jan 1, 2020

By G M. Thorpe

This paper discusses mine research at Inco, giving specific examples of research projects which illustrate the approach to mining problems. The first example covers the development of a new mining method, "undercut and fill," which was originated for mining badly broken-up pillars, but which is now rapidly replacing the square set method of pillar recovery. In the new method, ore is extracted in a series of successive horizontal cuts, progressing downward, a cut being completely mined and filled before the cut below is started. In the second example, improvements to the "cut and fill" method of mining are discussed. These improvements are the result of improved techniques and improved equipment, etc., with, in many cases, the former being made possible by the latter. The advances made have permitted the use of the "cut and fill" method at much greater depths than before. The third example is presented to illustrate research undertaken to obtain the earliest maximum advantage of the introduction of a new piece of equipment or material. For this purpose, the development of the "Under-ground use of AN /FO Blasting Agent " has been selected. Work on this project started in May, 1960, at a time when there was very little in-formation regarding the potentialities of AN /FO for underground blasting, either primary or secondary. By the end of 1961, AN /FO made up 64 per cent of the explosives used under-ground at Inco mines.

Jan 1, 1963

By M. Epiney, A. Ghahreman, R. Kim1and

"In the presence of sulfidic refractory ores, increasing the dissolved oxygen (DO) concentration can positively affect the gold leaching rate. To identify the role of DO in gold cyanidation, electrochemical behavior was studied in the presence of 3 different ores. Sample 1 was a low sulfide pyrite ore, contained 5.14% pyrite, 0.19% galena and 3.09% S. Sample 2 was a pyriticore as well, contained more sulfide as 8.35% S, and 12.4% of pyrite. Sample 3 was a tailing of silicate gold ore, still containing75 g/tAu, 0.13% Pb and 0.18% S. Gold cyanidation kinetics were studied by cyclic voltammetry (CV) and chronoamperometry tests. With sample 1, the gold oxidation peak current density from CV curve was increased to 1.38mA/cm2under oxygen injection, while it was only 0.66 mA/cm2with air injection. From chronoamperometry test, the reaction rate was also faster under oxygen injection. Sample 2 showed similar behavior with sample 1, but the gold oxidation peaks higher than sample 1, i.e. 1.75 and 2.27 mA/cm2, under air and oxygen injection, respectively. However, it seemed that the gold oxidation was impeded by sulfide ions for a longer period. In the presence of sample 3, the gold oxidation peak was the highest among three ores –2.75mA/cm2under oxygen injection, because of its lowest sulfide content. However, from chronoamperometry test, it was also shown that the gold oxidation was impeded because of a significant amount of Pb in the ore sample.INTRODUCTIONIt is well known that gold is leached under oxidative condition (Marsden &House, 2006). Through the most representative and oldest gold leaching technique, cyanidation, more than 90% of gold can be selectively leached from an ore. According to Elsner’s equation, gold is leached in cyanide solution by forming cyanide complex [Au (CN)2–], and oxygen is consumed as an oxidant(Eq. 1)."

Jan 1, 2017

By Tatsuya Oki

Tantalum capacitors can be found mounted on printed circuit boards of domestic appliances such as personal computers. These capacitors contain a considerable quantity of expensive metal tantalum and can be detached and liberated from printed circuit boards by impact breakers. In this study, the size and density distribution of the liberated electronic devices were investigated. Then, tantalum capacitors were recovered from other electronic devices using size separation and pneumatic gravity concentration methods. More than 70% of Newton's separation efficiency was obtained for tantalum capacitors. High Newton's separation efficiency could be also obtained for other types of electronic devices such as chip resistors.

Jan 1, 2011