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By D. G. Cerigo

"INTRODUCTIONAn interim report covering an uncompleted project on revenue mill optimization was presented at the invitation of Mr. C.S. Stevens, the Secretary of the Canadian Gold Metallurgists. The work described summarizes the preliminary work carried out at the Noranda Research Centre on computer mill optimization and is an attempt to arrive at a model of a circuit using the ""black box"" approach and hence by using economic factors related to concentrate dollar value to maximize revenue. The help and cooperation of Mr. J.D. Wild, Mr. M.J.S. Bennett of Noranda and Dr. A. Bobkowicz of McGill University is gratefully acknowledged.DERIVATION OF MODELHistorical data from the Normetal mill were used for the study. Normetal ore contains chalcopyrite, sphalerite, gold, silver, pyrite and pyrrhotite. For simplicity, data were chosen for days when only two concentrates had been derived, a copper concentrate which also contains the gold and silver, and a zinc concentrate. In these periods when pyrite concentrate was not produced, its circuit was used as an extra zinc scavenger unit. Figure I is a schematic drawing of the circuit and Table I explains the nomenclature.The mill had been operated to obtain a fixed grade of copper and zinc in the copper and zinc concentrates respectively, at the same time insuring acceptable recovery levels. The target grade for the copper and zinc concentrates had been derived by manual calculations based on past experience. The data used were 170 sets of daily mill reports, a sample of which is shown in Table II. The data consist of daily tonnages of feed, concentrates and tailings and their average compositions obtained by taking samples every twenty minutes from each stream and analyzing the daily composite samples."

Jan 1, 1967

By G. C. Laurence

"This paper discusses the hazards and extensive precautions taken in Canadian uranium mines, concentrating plants and processing plants. It also outlines Canadian policy regarding the control of the sale and distribution of uranium and other nuclear materials.OVER THIRTY YEARS AGO, I spoke to The Canadian Institute of Mining and Metallurgy here in Montreal about radioactivity and its dangers. I must have made quite an impression thirty odd years ago, because now you have asked me to do it again. Of course, the picture has changed. Then they were mining uranium ore, recovering the radium from it and throwing away the uranium. Now they are still mining uranium ore, but are throwing the radium out on the tailings dumps. Thirty years ago, most people did not know what ""radioactivity"" meant. Nowadays, they have beard that it is dangerous, and some of them, recently, be-came worried about the radium in the tailings dumps and what becomes of it."

Jan 1, 1969

By K. Reinharter, J. Schmidl, D. Gregurek, A. Spanring

Copper smelting furnaces are typically lined with magnesia-chromite refractories, which are exposed to multiple and complex stresses. The selection of the processing route, furnace type and slag system will be dictated by the specific ore type available, this will determine the individual refractory wear. This paper evaluates the common refractory wear mechanisms as observed in the copper Peirce-Smith converter and in the copper anode furnace. The chemical factors include corrosion caused by fayalite type slag and sulfur supply, as well as, by Cu-oxide attack. Changes in the temperature during the furnace operation (thermal-shock) create stresses in the brick lining which can only be absorbed in limited extent. Mechanical factors include erosion, caused primarily by the movement of the metal bath, slag and charging material, as well as, stresses in the brickwork due to punching. Finally improper lining procedures can also effect the service life. All these wear parameters lead to severe degeneration of the brick microstructure and a decreased lining life. Therefore, a detailed investigation and understanding of the wear mechanisms through “post mortem studies” together with thermochemical calculations by FactSageTM software is an important prerequisite for the refractory producer. Based on these research results, combined with specific process knowledge, appropriate brick lining solutions for copper processing furnaces can be recommended. INTRODUCTION The refining of copper includes converting of matte or black copper into blister copper for final fire refining process in the anode section. Typically Peirce-Smith (PS) converters are in use. Other technologies include Hoboken Converter, TBRC but also Flash Converting Furnace and bath smelting furnaces (ISA, Ausmelt) (Davenport et al., 2002). For fire refining two types of furnaces are used – the rotary furnace type is dominantly used in the primary production route while secondary smelters tend to use hearth refining furnaces which are more suitable for scrap melting. Installed working linings are based on magnesia-chromite bricks but especially in the anode refining section the application of alumina-chromia bricks have become more popular in the recent years. It comes without saying that, to some extent, large variations in the slag composition can be observed from the data provided to RHI Magnesita during post-mortem studies of used refractory samples and this needs to be addressed properly during the selection process of refractory linings.77

Jan 1, 2019

By N. Plint, D. Philips, J. Sweet, B. Durant

A pilot scale AG milling campaign was conducted at the AngloAmerican Platinum pilot plant in South Africa. Different blends of hard: soft (silicate: chromite) and coarse: fine particles in the AG mill fresh feed were tested. The effects of multi-component feed on the pilot scale autogenous grinding are presented in this paper, and can be used as a guideline for multi-component feed blends for AG mil

Jan 1, 2012

By LeRoy A. Thorssen

The use of lightweight aggregate as a constituent of concrete is not a recent development. Pumice was used by the early Romans, in pozzolana cement concretes, in the construction of many of their works. However, the recent development of manufactured lightweight aggregates, such as the expanded shales, vermiculite and perlite, has created a possible use for a whole new group of Portland cement concretes. Concrete can now be produced with unit weights ranging from 30 to 150 pounds per cubic foot and with various insulating, fireproofing, acoustical and structural properties. The tonnage of such materials being used has increased considerably in each of the past ten years, and can be expected to increase for the next several years as availability of the aggregates becomes more widespread and the properties of such concretes become more thoroughly investigated and more generally known. LIGHTWEIGHT aggregates of many types have become avail-able to the construction industry in most localities on this continent

Jan 1, 1963

By Guy Chevalier

QCM?s pellet plant, located in Port-Cartier, Quebec, produces up to 8.6 million tons of iron ore pellets annually. Four different types are produced: three for blast furnace operations and one for direct reduction furnaces. The paper presents the scientific approach that led to the installation of new process equipment to improve the reducibility of direct reduction pellets (DR pellet). The findings, the equipment selection and some post start-up modifications are presented. This low silica DR pellet is used in Midrex and HyL shaft furnaces. A good DR pellet has to meet strict chemical, physical and metallurgical specifications. An important metallurgical property is its ability to release oxygen when exposed to reducing gases. Considering that the market for DR pellets is expanding and being aware that reducibility is critical for our clients, a program to improve the latter was undertaken. Test work showed that one factor which has a negative effect on reducibility is the proportion of particles larger than 75 microns. Knowing that the best way to reduce the amount of coarse particles was to close our open grinding circuits, we began evaluating the most suitable classification equipment applicable to our process operations. We settled on hydro-classifiers based on their very sharp cut and their low operating costs. In light of the hydro-classifiers performance it was also decided to replace the hydro-cyclones of an already closed circuit.

May 1, 2003

By Simon C. Dominy, Patrick R. Stephenson, Alwyn E. Annels

Abstract - The often complex, erratic, and localized nature of gold is a common feature of many vein-style gold deposits. This style of mineralization is often referred to as being nuggety or possessing a high-nugget effect. As a result of these complexities resource estimation is difficult and in general, only Exploration Results can be provided or an Inferred Mineral Resource estimated from surface drilling data alone. Underground development, further drilling, and probably bulk sampling will be required to delineate Indicated and Measured Resources. Tonnages can generally be estimated from diamond drill and development information with a reasonable degree of confidence. Grade is much more difficult to define with confidence because it is commonly highly erratic and discontinuous in nature. The dependency of higher confidence Resource categories on development information may create a Catch 22 situation, with funding for such development often depending on the prior definition of at least Indicated Resources. There are no easy solutions to these challenges posed by high-nugget effect deposits, and it is important when classifying and reporting not to downplay the uncertainties often associated with Mineral Resource and Ore Reserve estimates for such deposits. However, in common with all deposit types, if the principles that underpin the estimation, classification, and reporting procedures are borne in mind and common sense applied, most issues can be satisfactorily resolved. This paper discusses the classification and reporting of Mineral Resources for high-nugget effect gold vein deposits within the framework of the JORC Code (JORC, 1999).

Jan 1, 2001

By Yolaine le Beau

Plan de la présentation Le contexte mauritanien La situation de l?environnement en 1999 L?évolution de 1999 à 2010 Bilan La situation de l?environnement en 2011 Le contexte mauritanien Pays du Maghreb couvert à 75% par le désert du Sahara Un des plus pauvres au monde Index de développement humain : 136esur 169 pays en 2010 46,7% de la population ne peut subvenir à ses besoins quotidiens

May 1, 2011

By Andre Vien, D. H. Hendriks, D. Willet, B. C. Flintoff

"For many years the training of mill operators was an informal process which involved senior operators training junior operators on an as-needed basis. Recognizing the needs and benefits of better training some companies, and even some provinces through legislation, have moved to ensure that a formalized training program exists in the plants. These programs tend to focus on basic safety and operations. Much remains to be done. With the more rapid incorporation of new processing and information technologies, and the goal to keep labour costs to a minimum by doing more with less, operator training has become a critical issue. This paper briefly examines the evolution of training programs, provides some measure of their effectiveness, and explores some recent developments which could have a very significant impact on the industry.PreambleOne can draw an analogy between operator training and the mechanical support of production equipment. When we buy a piece of process equipment it is critical that the mechanical installation be done properly to ensure that the device will operate at peak performance on start-up. Once the equipment is running, some form of preventive maintenance is required to ensure continued efficient operation. The operators and the equipment are both elements of the processing system, yet the former do not seem to get the same ""start-up"" or ""operating"" support. Are they not seen as critical to efficient operation? Why is this so? What impact does it have? How can we improve?These are all very logical and important questions, although the answers are not nearly so obvious. In the mineral processing industry, progress in operator training over the past thirty years has been limited and quite variable. To address the perceived need for a more coherent and consistent approach, some provinces have moved to incorporate basic training requirements in their legislation. Some plants have gone a few steps further by building integrated training programs into their operating culture. One conclusion which can be easily reached is that there are no standards, and that the range of training activity is great. In other words, a flotation operator is not a flotation operator is not a flotation operator. Their knowledge and skills are very much a function of training and experience, which are clearly corporate and site specific."

Jan 1, 1994

By H. Gharahbagheri, S. Shafiei Zadeh, H. Hassan Nejad

Waste Electrical and Electronic Equipment (WEEE) is one of the fastest growing types of solid waste in the world, and often contains precious metals, especially gold. Gold processing and recovery from secondary materials, especially WEEE, have been under investigation for more than a decade now; however, a comprehensive review that illuminates the future path is missing in the literature. The aim of this short paper is to discuss the recent advances in gold processing and recovery from secondary electronic materials and why it has not yet become practical. The role of pyrometallurgical and hydrometallurgical methods, as well as their advantages and disadvantages will be discussed; however, the focus will be on Biosorption and recent advances.

Jan 1, 2014

By Daniel Gendron, Luc Morin

"Concentrate sampling is a growing concern in the world's mining and smelting industry. The main modes of transportation for concentrate to the smelter are by truck or rail car in a bulk form, thereby limiting access to sample extraction equipment. In many cases, concentrate is shipped to a smelter by several suppliers therefore requiring individual manipulation of different customer samples in a safe and reliable manner. The Heath & Sherwood Bulk Product Sampler offers this feature as well as an economical and effortless way of obtaining samples in rail cars or truck boxes.In 1994, Noranda Metallurgie in Rouyn-Noranda, Québec purchased a self contained Bulk Product Sampler to extract samples directly from inside rail cars before unloading the concentrate. After testing and comparing the results with the conventional sampling method, the bulk product sampler proved to be a practical and advantageous solution for concentrate sampling both for the customer and smelter. Since its installation at the Horne smelter in Rouyn-Noranda, the Bulk Product Sampler has been steadily used on rail cars which contain concentrates from around the world."

Jan 1, 1996

By Z. D. Hora

Several deposits of crystalline magnesite are known in southeast British Columbia. Deposits at Cross River and Marysville have been thoroughly explored, but as yet there has been no commercial production.

Jan 1, 1984

By Paul G. Dunn

Safe rapid drift development results principally in reducing exposure of underground workers to the working face. This reduction in exposure is not achieved until either the rock walls have been suitably scaled or sufficient support has been put in place. Rapid drifting enables quicker access to orebodies (increasing returns), higher production rates and a resultant lower cost of mining. The Mining Innovation, Rehabilitation And Applied Research Corporation (MIRARCO) has been developing technology and a methodology for safe rapid drift development within the underground metalliferous mining industry. In terms of rock scaling for underground metal mines, there is still considerable use of manual and mechanical impact rock scaling techniques. Two main issues result from this approach. The first is that in highly stressed or highly fractured ground, a decision has to be made as to when sufficient scaling has taken place. This is not always easy to do and hence operator judgment is a crucial element in this approach. During a baseline study of current rock scaling practices, a wide range of scaling practices were observed within five different underground mining operations; this demonstrates the difficulty inherent in the rock scaling quality decision making process. The second issue is related to the exposure of workers to freshly created rock surfaces. In manual scaling techniques this is unavoidable and despite the best scaling practices, accidents still occur. In an attempt to provide an alternative scaling technology, MIRARCO has been investigating highpressure water jet scaling for removing loose rock as part of the drift advance process. This technology not only provides a means by which scaling practices can be engineered (remove the loose material you want to in a given rock mass condition), it is also quicker and easily automated. Automating the scaling process removes workers from exposure to freshly created rock surfaces and also enhances the application of spray-on liners through improved adhesion of these support types to the rock surface. This paper describes the water jet scaling technology research and methodology for safe rapid drifting within the underground metaliferous mining industry and highlights the key issues and major drivers behind their continued development at MIRARCO.

May 1, 2004

By R. H. Seraphim

"The Phoenix Camp, in the Boundary Creek district of southern British Columbia, produced before 1920 about 15 million tons of ore averaging more than l ·5 per cent copper, about 0.03 ounces per ton in gold, and 0·5 ounces per ton in silver. Attwood Copper Mines Ltd. conducted an exploration program in the Phoenix area from 1951to1953.Publications on the camp are listed in the bibliography. Brock's work was not sufficiently detailed to unravel the structural and stratigraphic pro bl.ems. The work of LeRoy and McNaughton is referred to later.The stratigraphic column is as follows:Tertiary.Midway Formation: Volcanics and hypabyssals; dacitic to basaltic flows, with associated dykes and sills of syenite (pulaskite in part) and augite porphyry.Jura-Cretaceous.Intrusives of quartz diorite and diorite (nearest outcrop two miles from Phoenix).Late Palaeozoic or Triassic (Attwood Series).Brooklyn Formation: Sharps tone conglomerate, limestone, grey-wacke and/ or andesitic tuff, with minor shale and basalt. Rawhide Formation: shale with minor conglomerate.Early Palaeozoic.Knob Hill Formation: Chert and andesite, with minor limestone, shale, and serpentine.This column differs from that of LeRoy in two important respects: (I) Attwood's work indicates that the Rawhide shale is basal to, rather than stratigraphically above, the Brooklyn formation. The shale contains conglomerate lenses, which become more abundant and thicker toward the top, and grades upward into Brooklyn conglomerate. Ripple marks indicate that the shale is right side up."

Jan 1, 1949

By J. D. Templeton

A petroleum well that is not in use because it has ceased to produce oil/gas economically and dry holes are referred to as abandoned wells. Once a well is abandoned it is plugged with cement and can take anywhere from two days up to a week to cure depending on the number of plugs in the well. Since plugging a well costs capital, most wells are abandoned at the lowest possible cost and with the minimum obligations set by regulation agencies. These wells can present an enduring liability to petroleum companies. However, the depth and abundance of abandoned petroleum wells makes them an economically attractive source of geothermal energy. Geothermal energy harvested from an oil/gas well is a renewable energy source as long as it is extracted in a sustainable manner. The energy can be used to generate electricity, used directly for heating, incorporated into a water desalination process, or used by a heat pump for heating/cooling applications. In this paper we examine the possibility of extracting geothermal energy from abandoned oil/gas wells by studying the heat transfer in underground geothermal heat exchangers installed in these wells. The design configurations for the geothermal heat exchangers embedded inside a petroleum borehole can be a u-tube design or a shell and tube design (i.e. double pipe). Using in-situ gathered information from some representative petroleum boreholes, the effects of key parameters such as geothermal gradient, ground temperature values, and the flow inside of the tubes are evaluated. In order to provide a constant power production the inlet temperature can be adjusted to keep the difference between outlet and inlet temperatures equivalent. Higher differences between inflow and outflow temperatures will result in a less sustainable load put on the in-situ geothermal energy. Adding insulation to certain sections of the designs can minimize the transfer of thermal energy from the fluid to the surroundings. Insulation can also limit the thermal loss between the inflow and outflow tubes in the shell and tube design. Minimizing the energy loss of these designs leads to an increase in the outlet temperature, meaning a higher grade of heat. The sustainability of long term geothermal heat extraction is a balance between the rate at which geothermal energy is extracted and the rate at which the ground formation can replace this heat. Higher outlet temperatures can lead to a larger amount of power generation, and a higher coefficient of performance for heat pump applications.

Aug 1, 2013

By Adriana Ramirez, Bradford C. Wesstrom, Blanca Olave

The Freeport McMoRan El Paso Copper Refinery optimizes electrolyte quality using a number of systems. The facility controls copper, arsenic, antimony and bismuth using electro-winning cells within the Tank House and Nickel Carbonate Plant Liberator Circuit (NCP). The NCP manages sulfuric acid content utilizing recycled electrolyte in the slimes autoclave as well as operation of the Acid Purification Unit, APU. The El Paso Refinery removes common sulfates using metal hydrolysis with sodium carbonate. Finally, a Mechanical Vapor Recompression, (MVR), at the water recovery plant removes sodium sulfate generated by the NCP. This paper will provide a summary of these operations. INTRODUCTION In the mid 1920’s Nichols Copper Company, in Laurel Hill, New York, recognized the need for a modern copper refining facility in the southwest. Because of the many railroad heads, affordable power and abundant labor supply, and the close proximity to regional copper smelters in Mexico, Arizona, and New Mexico, El Paso became the ideal location. In December 1928, ground was broken for the joint venture refinery between the Nichols Copper Company, Phelps Dodge, and the Calumet and Arizona Mining Company. In September 1930, Nichols Copper Company became a part of Phelps Dodge Corporation after a stock exchange. In July 1938, Nichols Division officially became Phelps Dodge Refining Corporation. In March 2007, Freeport McMoRan Copper & Gold acquired Phelps Dodge. Water is a precious commodity in the desert southwest, making conservation of this natural resource an important goal for the El Paso Operations. In the 1980’s, work on the treatment of slimes was improved through the use of pressure leaching of the refinery slimes using an autoclave. Due to the high tellurium content in the leached slimes solution, it was crucial to implement a method for its removal before the solution returns to the tank house electrolyte. A copper telluride cementation operation was installed for tellurium recovery and the ability for the recycle of the leachate and wash water to the refinery electrolyte. In October of 1997, ground was broken for the construction of the water recovery plant using an MVR to reuse process water, reducing water consumption by 25%. In 2002, electrolyte purification was further improved with the installation of an Acid Purification Unit, (APU) (Sheedy, Pajunen, & Wesstrom, 2007). The APU recycles 90% of the acids (both sulfuric and arsenic acids) back to the tank house electrolyte. The solution that passes through the APU is treated with soda ash to precipitate metals out of solution as carbonates and generates a sodium sulfate solution. This sodium sulfate solution is easily processed in the new water recovery plant, where the majority of the water recycles back into the plant as pure condensate. In 2012, the power plant at the refinery upgraded its Reverse Osmosis System to provide RO water to the tankhouse. This insured that the refinery would not have to bleed electrolyte for metals contained in well water such as: calcium, magnesium, iron and sodium chloride.

Jan 1, 2019

By Robert B. Parsons

"Canadian investment abroad has been the focus of considerable attention in recent years. Canadian mining companies have been heavy investors in Latin America and are taking a hard look at Central Asia and the Pacific Rim. This international flow of capital is not one-way however. Foreign mining companies continue to make substantial investments in Canada's mining industry. This month. Tax Notes addresses some of the main Canadian income tax implications of foreign investment in Canada.Foreign Investment in CanadaThere are two basic forms of foreign investment in a Canadian company: share capital and debt. The following comments deal with each of these investments separately. It is appreciated that the relevant tax legislation is, as always, quite complex, and that the notes that follow are intended only to serve as a guide. This article should not be relied on as a substitute for professional advice."

Jan 1, 1994

By Timothy W. Ellis

Gold-based materials have been a mainstay of the electronics and semiconductor industry since the physics was just a laboratory curiosity. Gold is the workhorse material in wire bond, flip chip and off wafer interconnections due to its corrosion resistance, ability to form metallurgical bonds by soldering or cold welding, and ease of fabrication. As the electronics and semiconductor industries grew, so did the use, of Gold in spite of the feature size reduction so elegantly demonstrated in Moore?s law. However, several revolutions in the Silicon miracle are threatening Gold?s place as the material of choice. Although cost is always an issue, the limitations are associated with the chemistry of Gold based alloys. Will Gold remain? Emerging requirements of bioelectronics, photonics and power requirements in conventional device represent new opportunities for Gold to shine. Additionally, as the world market demand for electronic, semiconducting, bio-electronic and photonic technology increases, given the right technology, Gold still can provide value proposition.

Oct 1, 2003

By Xiaolin Cheng, A. J. Sinclair

"Norm calculation procedures originally designed principally for igneous rocks are very rigid in their application and, in general, do not utilize important alteration minerals. For instance, volatile components are essential constituents of many metasomatic rocks but either are not used or are not used effectively in determining normative minerals by the CIPW norm or Niggli-Barth norm procedures. Our approach to determining norms for metasomatic rocks allots all major, minor and volatile constituents to a set of standard normative minerals which are commonly observed as products of hydrothermal alteration. A useful procedure is to have a metasomatic norm approximate the mode as closely as possible. Petrographic information helps to provide the necessary mineralogical constraints. With the recognition of an immobile component and knowledge of sampling and analytical errors in lithogeo chemical data, it is possible to recast norms into amounts of alteration minerals relative to a given amount (100 grams) of parent rock. Combining these results with the calculations of absolute loss or gain of individual chemical constituents and considering errors (e) for an appropriate confidence level, an overall (net) material exchange equation can be presented as follows:<equation>where all items have extensive units (e.g., grams). The model includes the initial and final mineralogy of rocks (evident in the field) as well as gains and losses of specific elements. Only those constituents whose calculated losses and gains are significantly different from zero are retained in the above model, and only the normative minerals with abundances significantly different from zero are included in the model (equation). One advantage of the chemico-mineralogic model is that parent rock and product are modeled in mineralogical terms that are familiar to and easily usable by exploration geologists."

Jan 1, 1995

By Xiaolin Cheng, A. J. Sinclair

"Abstract - Norm calculation procedures originally designed principally for igneous rocks are very rigid in their application and, in general, do not utilize important alteration minerals. For instance, volatile components are essential constituents of many metasomatic rocks but either are not used or are not used effectively in determining normative minerals by the CIPW norm or Niggli-Barth norm procedures. Our approach to determining norms for metasomatic rocks allots all major, minor and volatile constituents to a set of standard normative minerals which are commonly observed as products of hydrothermal alteration. A useful procedure is to have a metasomatic norm approximate the mode as closely as possible. Petrographic information helps to provide the necessary mineralogical constraints. With the recognition of an immobile component and knowledge of sampling and analytical errors in lithogeochemical data, it is possible to recast norms into amounts of alteration minerals relative to a given amount (100 grams) of parent rock. Combining these results with the calculations of absolute loss or gain of individual chemical constituents and considering errors (e) for an appropriate confidence level, an overall (net) material exchange equation can be presented as follows:SMineralparent rock ± e + SConstituentgained from solution ± e= SMineralaltered rock ± e + SConstituentlost from wall-rock ± ewhere all items have extensive units (e.g., grams). The model includes the initial and final mineralogy of rocks (evident in the field) as well as gains and losses of specific elements. Only those constituents whose calculated losses and gains are significantly different from zero are retained in the above model, and only the normative minerals with abundances significantly different from zero are included in the model (equation). One advantage of the chemicomineralogic model is that parent rock and product are modeled in mineralogical terms that are familiar to and easily usable by exploration geologists."

Jan 1, 1995