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By Karen Munro

Importance of Aquatic Studies for Mining ?Aquatic habitat is usually the first area where a mine interacts with the ?real world? outside the mine footprint ?Water management is a key consideration for a mine?Effects on the aquatic environment often extend to wildlife and human uses ?There is a lot of regulatory focus on issues of water quality, fish and fish habitat

May 1, 2011

By Doris Stüben, Geoffrey P. Glasby, Akira Usui, Jörg-Detlef Eckhardt, Bruce W. Mountain, Zsolt Berner

"Abstract - Twenty-seven marine Mn and Fe deposits chosen for their diverse origins have been analyzed for five platinum-group elements (PGE). The PGE display their highest concentrations in hydrogenous Mn crusts and nodules, lesser concentrations in diagenetic nodules and two to three orders of magnitude lower concentrations in hydrothermal Mn and Fe crusts. This difference of behavior reflects the well-known fractionation of Mn and Fe from the other transition elements, rare earth elements (REE) and PGE in hydrothermal Mn and Fe crusts. Pt, Ru, Rh, and Ir show a close geochemical coherence in these deposits and are differentiated from Pd which shows a negative anomaly with respect to the other PGE in hydrogenous and diagenetic Mn deposits. Pd is less depleted than the other PGE and the Pd anomaly much less pronounced in the hydrothermal Mn and Fe crusts relative to the hydrogenous and diagenetic Mn deposits.Stability field diagrams show no evidence for the oxidation of Pt to the tetravalent state in seawater as suggested by some authors. Rather, Pt appears to be present in seawater as Pt(OH)2 0. Adsorption of Pt(OH)2 0 onto the surface of Mn and Fe oxyhydroxide minerals may explain the enrichment of Pt in marine Mn deposits. However, Pt metal is the thermodynamically stable solid phase of Pt under seawater conditions and reduction of Pt(OH)2 0 to Pt metal, particularly in the vicinity of the oxygen minimum zone, is possible, although the high Ce/La ratios of the Co-rich Mn crusts do not support this hypothesis. Pt, Ru, Rh, and Ir display their maximum concentrations in the Corich Mn crusts. This may reflect, among other things, the low growth rates of these deposits. The stability field diagram of Pd shows that Pd is undersaturated in seawater and occurs in seawater dominantly as PdCl4 2- and anionic mixed-hydroxide-chloride complexes. This would explain the anomalous position of Pd among the PGE with respect to its uptake into marine Mn deposits. A study of inter-element associations indicates that the incorporation of the PGE from meteoritic dust plays only a minor role in the uptake of these elements into marine Mn deposits. The PGE remain the most poorly studied group of elements in marine Mn deposits. The data presented here emphasize the need for the establishment of a more comprehensive database of the PGE in marine Mn deposits in order to understand more fully their uptake into marine Mn deposits and their pathways through the oceans."

Jan 1, 1999

By Helen Shang, Jianjun He

In nickel and copper production, sulfur dioxide (SO2) is generated during mineral smelting. Emission of sulfur dioxide into the atmosphere causes serious health and environment issues. Sulfuric acid plants, which convert the harmful SO2 gas to commercially useful sulfuric acid product, ensures safe and environmentally sound smelter operations. The sulfuric acid plant is mainly composed of a SO2 to SO3 converter, a series of heat exchangers and SO3 absorption towers. The SO2 converter is crucial for minimizing SO2 emission in a smelter. In this paper, steady state and dynamic modelling are carried out for the converter using mole and energy conservations. Simulations are performed to investigate the effect of feed conditions on SO2 conversion. The developed model represents an important component for modelling the acid plant in a smelter and is expected to provide a fundamental tool for the future optimization and control development.

Jan 1, 2014

By G. D. Mcdowell, L. B. Cochrane, B. D. Thompson

"Abstract - Exploration for deep underground copper and nickel sulfide deposits in the Sudbury mining camp is carried out with surface drilling. More detailed drilling, with an advanced underground exploration program, may be necessary to establish an accurate interpretation of the deposit geology and upgrade the resource estimate to the measured category for reserve estimation and feasibility assessment. Resource evaluation is a lengthy and costly process that could result in a decision not to proceed with the project. For projects that proceed to production, significant reductions in the operating and capital costs could be achieved with a more accurate interpretative model of the deposit geology and mineralization. Quality control procedures to ensure the integrity of the drilling data and interpretation guidelines are essential steps in the development of a deposit model. The use of block modeling techniques and the application of geostatistics for resource estimation further improve the quality of the resource model.Significant improvements to the interpretive models can also be achieved by incorporating additional information from geophysical measurements to validate and constrain the geological interpretation. The geophysical models must be consistent with known geological environments and oreforming processes, which has required the concurrent development of comparative models from exploited deposits. These geophysical techniques can also provide key geotechnical information required for the optimum design of the mining method and mining sequence. The objective of this program is to improve the accuracy of the deposit model and the quality of the resource and reserve estimates in order to optimize capital investments and reduce the development and operating costs of underground mining projects. Several of these techniques are currently being tested at INCO Limited’s Sudbury operations. The results from those tests are presented and their applications are discussed within the framework of resource/reserve classification systems and project evaluation objectives."

Jan 1, 1998

By R. S. James, S. P. Goff, A. E. Armitage

"Oxide-facies banded iron formation in the Third Portage Lake area is hosted by ultramafic and calc-alkaline volcanic rocks and related sedimentary rocks of the Archean (2.8 Ga) Woodburn Lake Group, 80 km north of Baker Lake. These rocks record at least two phases of metamorphism/ metasomatism. Greenschist facies metamorphism, in the temperature range of 370°C to 520°C and at pressures above 2.3 kbar, has affected all rocks on a regional scale. Later mineralization and alteration of banded iron formation (BIF) and associated volcanic rocks resulted from metasomatic fluids which carried Mg, K, Ca, S, As, Cu and Au. These fluids were confined to ductile to brittle, cross-cutting and layer-parallel micro-shears developed in the thickened hinge region of a shallow plunging recumbent fold. Metasomatic reactions yielded cummingtonite + biotite-bearing assemblages which are associated with strongly mineralized iron formation. Pyrrhotite is the dominant sulfide phase and occurs within ductily deformed iron formation where it pervasively replaces magnetite. Minor fine-grained chalcopyrite and arsenopyrite generally occur as inclusions within pyrrhotite and recrystallized magnetite, and rarely as individual grains. Pyrite is restricted to brittlely deformed iron formation, and to the contact between iron formation and altered ultramafic rocks, where it is associated with quartz veins. Pyrite typically replaces pyrrhotite. Native gold is associated with both pyrrhotite and pyrite, but higher gold concentrations are associated with pyrite. Grunerite/Ca-amphibole + stilpnomelane and sparse pyrrhotite and pyrite characterize weakly mineralized iron formation. Within adjacent ultramafic rocks, metasomatic reactions yielded assemblages of interlayered Ca-amphibole + biotite, and talc + Ca-amphibole + carbonate + biotite. K-Ar geochronology on metasomatic biotite from mineralized BIF yielded a 1791 ± 32 Ma age.An epigenetic model is favored for the emplacement of gold. The age of the gold mineralization in the Third Portage Lake area is uncertain, but may be Proterozoic based on the preliminary isotopic age and by analogy with Proterozoic gold deposits elsewhere in this part of the Churchill Structural Province. Copyright"

Jan 1, 1996

By W. J. Mcgaughey, M. A. Vallée

"Abstract -The application of geophysical technology to resource delineation aims to improve the quality of resource/reserve estimates by integrating high-resolution survey methods, geophysical modeling and inversion with three-dimensional representations of geological and mineral deposit data. The use of geophysics can cost-effectively improve a geological interpretation based only on geological and sampling data. Success depends upon the ability to use geological visualization and modeling software, first to develop a three-dimensional geological model and then to modify it interactively by integrating geophysical data with the geological and sampling data.The high resolution required for mineral delineation geophysics results in a focus on borehole seismic and high-frequency electromagnetic methods. Borehole wireline logging is used to develop an understanding of the relationship between physical properties and geological description. Data from core samples and borehole wireline logs allow the construction of a three-dimensional physical property distribution, consistent with the existing geological interpretation. The three-dimensional physical property distribution is used for both geophysical forward modeling (to compare to field data) and as a starting model in iterative inversions.Advanced visualization techniques allow the simultaneous viewing of the three-dimensional physical property model, the geological information and data from which it is derived, and the geological interpretation and the geophysical results. Geophysical results may be simulated responses from a forward model or the output from a numerical inversion in the form of an updated physical property distribution. Iterative refinement of the geological interpretation is required to ensure consistency with the geological and geophysical data. The key to success with this approach is that all relevant geological, geophysical, and rock property data reside in a common, visual model of the earth.Examples from massive sulfide deposits illustrate the benefits obtained by the integration of geophysical and geological data."

Jan 1, 1998

By Shila Jafari, Mari Lundström, Aleksei Kritskii, Pia Sinisalo

A typical process adopted at nickel plant is the processing of nickel-copper mattes and converter mattes using the following technology: pressure oxidative leaching (POX), solvent extraction (SX), electrowinning (EW), cobalt recovery, and solutions purification. As a result of multi-stage atmospheric and autoclave process leaching, copper-nickel separation is achieved. Cobalt and nickel are further separated by SX. Copper in the process can be removed as copper cake (Cu-cake), which is a by-product with high content of valuable metals. In the current paper, a method combining atmospheric and pressure leaching of Cu-cake in sulfuric-acid media is discussed. Suggested method allows to obtain high copper extraction (>98%), with leach residue containing precious metals and PGMs. Sulfuric acid media was chosen to make the suggested technology adaptable for the primary POX-SX-EW circuit. The initial Cu-cake was analysed and a range of process parameters (t = 25–190°C; PO2 = 0–7 bar) investigated to achieve the optimal conditions for leaching process at the ambient as well as at increased pressure. As a result, an initial process block diagram for the treatment of Cu-cake with high copper leaching efficiency and low metal losses is provided. INTRODUCTION The conventional technology for nickel sulphide ore processing includes the following main stages: froth flotation, matte smelting and converting. The subsequent processing of nickel converter matte is possible using fundamentally different approaches - hydrometallurgical (Llanos, Queneau & Rickard, 1974; Rademan, Lorenzen & Van Deventer, 1999; Kshumaneva, Kasikov, Neradovskii & Belyaevskii, 2009; Dutrizac & Chen, 2013) and pyrometallurgical (Tsymbulov, Knyazev, Tsemekman & Golov, 2007). Hydrometallurgical approach in comparison with pyro-process has several advantages, such as reduced environmental load, reduced PGM losses, increased copper and nickel extraction. Typically, hydrometallurgical technologies include leaching, solvent extraction as well as nickel and cobalt recovery in metallic form by electrowinning or hydrogen reduction or as valuable metal salts via crystallization process (Crundwell, Moats, Ramachandran, Robinson & Davenport, 2011).

Jan 1, 2019

By Donald A. Cranstone

"This paper provides a bird's eye view of the pattern of gold discoveries since 1823, the year of Canada's first gold find, up to 1983. Within this 160-year period, more gold was discovered in Canada during the last ten-year period (1973-1982) than during any previous decade. The record suggests that the potential for further major gold discoveries is high, which bodes welt f or the future of Canadian gold mining.IntroductionCanada has an impressive history as a gold producer. Since 1921 we have occupied second or third place among the world 's gold producing nations, after South Africa and most of the time the U.S.S.R. Canadian gold production over the last hundred years has added up to some 6 per cent of all-time world production.The sharp rise in the price of gold in the 1970s led to a surge of gold exploration, which in turn resulted in the discovery of significant quantities of gold in Canada. How do these recent discoveries rate in comparison with those of the more distant past? For example, are the quantities of gold in notable discoveries of recent year s, such as Hemlo and Detour, in the same league with the amounts of gold discovered around 1910 in the Porcupine and Kirkland Lake district s of Ontario? Can the combined gold content of the recent discoveries be likened to that o f the almost 40 major Canadian gold deposits, along with numerous smaller ones, discovered in Canada during the 1920s and 1930s? What are the implications of the more recent gold discovery record for future rate s of gold discovery in Canada?This paper attempts to glean answers to such questions from an overview of the period that begins in 1823, the year of Canada's first gold discovery. Gold deposits come in two major types: placer deposits and lode deposits in solid rock . Placer gold is distributed in sand and gravel. Gold in solid rock occur s mostly in gold ore filling fissures."

Jan 1, 1985

By J. E. Nesset

The past 50 years have been a golden era, not just for the CMP but also for the development and success of Canadian technologies in the field of mineral processing. The CMP has played a critical role of technology transfer agent, and the success of these technologies is also linked to the success of the CMP itself. The presentation will cover, in brief, the growth of the CMP from its origins as the Canadian Gold Metallurgists in 1964, with some 39 attendees, to the present day when the annual meeting sees 500 and more from a dozen countries. Also covered will be selected technology success stories from the 50th anniversary volume to be given to all delegates ‘Canadian Contributions to Mineral Processing Technology 1968-2018’. The volume itself highlights some 40 technologies that have been divided into five categories; process water treatment and minesite environment, technology innovations, innovations in operations, technology providers and university contributions. Some international perspectives will also be shared.

Jan 1, 2018

By Jian Li, V. Y. Gertsman, David C. Katz, M. Elboujdaini

Analysis of stress corrosion cracking (SCC) usually involves high-end analytical tools including scanning electron microscope (SEM) and analytical transmission electron microscope (TEM). In recent years, focused ion beam microscope (FIB) has found many applications in materials science fields. In this study, high-resolution FIB images have shown details of crack morphology and a plan-view TEM specimen containing the selected crack-tip was successfully prepared. The preparation of cross-sectioned samples containing crack tips was of paramount importance for subsequent TEM analyses.

Jan 1, 2004

By Fathi Habashi

A new era in pressure hydrometallurgy is marked when the roasting - leaching - electrowinning process in the zinc industry was replaced by direct pressure leaching of zinc concentrate. Since then, the technology has received recognition as the technology of the future. Large autoclaves of unprecedented size have been manufactured and installed in a number of metallurgical plants for recovering copper and nickel from their concentrates or liberating gold from its refractory ores. An attempt to recover alumina from clay using pressure technology is underway. Autoclaves lined with acid resisting bricks or with titanium clad may weigh as much as 800 tonnes were transported successfully from the manufacturing workshop to the mine site over long distances.

Jan 1, 2014

By Rodney A. Cooper

The Mary River iron ore deposits were discovered in the 1960?s. The high quality of the deposits was immediately evident, and drilling programs were successful in defining a resource adequate for supporting a feasibility study. Through a combination of ownership, market and political forces, the deposits were not developed. Having missed the window of opportunity, the project remained dormant for over three decades. Baffinland Iron Mines Corporation, with its 100% ownership of the Mary River deposits, began trading publicly in 2004. Modern exploration and metallurgical test work began in 2004 and has continued in 2005 and 2006, resulting in total expenditures during this period of almost C$60 million. In May 2006, an engineering team lead by Aker Kvaerner E&C, a division of Aker Kvaerner Canada Inc., completed a scoping study based on the first of five identified deposits. Highlights of that study include direct shipping of high quality lump ore to Europe over a 34 year mine life at a production rate of 10 million tonnes per annum, based on an indicated resource of 309 million tonnes at 66.1% Fe and an inferred resource of 28 million tonnes at 65.9% Fe. Capital costs were estimated at C$1.5 billion. Using iron ore prices approximately 36% below that of the 2006 market, a pre-tax internal rate of return of 15% was estimated assuming equity financing. Payback on initial capital was 5.9 years. The pre-tax life-of-mine cash flow was estimated to be C$6.3 billion. As a result of this study, Baffinland initiated a Definitive Feasibility Study, under the management of Aker Kvaerner, which is scheduled for completion in December 2007. This paper touches on the geology of the deposits, the current resource and the outlook for expansion. Project permitting, construction planning, logistical challenges and ocean shipping considerations are discussed, providing a current perspective on the project scale, scope and timeline for commercial production. In addition, an overview of the Company?s bulk sampling program will be provided.

May 1, 2007

By Ch. Wenzl

Anodes must have a certain physical and chemical quality in order to provide uniform anodic corrosion and meet the requirements of electrorefining, i.e. to achieve a high current efficiency, low energy consumption, low amount of anode scrap and low effort together with high cathode quality. Various properties of the anodes can be influenced directly by the casting process, which is the interface of pyro- and hydrometallurgy of copper. The aims of anode casting ? high output and long mould lifetimes ? are not consistent with good physical anode quality. The physical requirements of an anode are smooth surfaces, uniform weight and thickness, minimal edge effects, minimal distortion of the body and the lugs, as well as a homogeneous microstructure, in order to achieve uniform dissolution behaviour. The chemical quality of the anode copper is a task of electrorefining operations, but the elemental distribution within the anodes, which should be as homogeneous as possible in order to provide uniform anodic corrosion, can be influenced by the casting process.

Jan 1, 2007

By D. Harris, S. Murugesan, G. Ye, G. Oprea, J. Rigby, T. Troczynski

The spinel-added and in-situ spinel bonded castables have been developed and widely used in steel industry. It is challenging to develop magnesia-based castables for the non-ferrous industry because the temperatures in industrial furnaces are significantly lower than those in the steel industry and therefore the binding systems of these castables must have the capability to develop a ceramic matrix below 1300°C. It is also challenging to develop a good binding system without addition of fume silica, because the hydration of magnesia may take place during installation, curing and firing of the castables. This work presents the experimental results on developing magnesia-based cement-free, silica fume-free refractory castables using hydratable alumina as the hydraulic binder and a spinel phase as the final ceramic binder. In order to activate the sintering and have a ceramic matrix well developed at the relatively low required temperatures, ultrafine aluminas, chromia, magnesium-aluminate spinel and aluminum titanate powders were used as components of the binding system.

Jan 1, 2004

By Todd Smith

AGENDA Newalta overview Dewatering underground slimes: current technique & challenges Why centrifugation? Process improvements & advantages How centrifuge technology works Implementation: first step Summary of benefits

May 1, 2013

By Matt Manson

Renard?1-10 kimberlite pipes and ?Lynx-Hibou?kimberlite dyke system within ?Foxtrot?property 50/50 JV with SOQUEM, Stornoway operator 2001: Discovery of the Renard kimberlite pipes 2003: Discovery of the Lynx-Hibou kimberlite dykes 2006-2007: Bulk sample program 2008: First 43-101 Resource and Preliminary Assessment 2009/2010: Updated 43-101 Resource

May 1, 2010

By J. A. Hudson

"The paper begins with a brief summary of Professor Müller’s formation of the ISRM and the contents of the previous six Müller lectures with their emphases on rock fractures. The geological origin of fractures is described via a deformational spectrum diagram and a matrix characterising the consequences of a sequence of superimposed deformational events. The different fracture frequencies encountered along lines in all directions through a fractured rock mass are explained. The value of computer modelling and simulation is demonstrated through an example of the effects of fracture zones on the distribution of the in situ stress field. The need to establish the validity of computer programs, i.e., that the modelling/simulation, does actually represent the rock reality, is discussed with reference to the work of the DECOVALEX project. Finally, examples are given of the effects of rock fractures on engineering design and construction, from pre-split blasting to caverns.INTRODUCTIONIt is a great honour to have been chosen as the recipient of the ISRM 7th Müller Award and I am grateful to the representatives of the International Society for Rock Mechanics (ISRM) National Groups who voted for me. In addition, I am especially pleased because my working life in rock mechanics and rock engineering has been devoted to understanding the geometry and mechanical properties of rock fractures and rock masses—which were the key subjects that Professor Müller promoted. In the ISRM 50th Anniversary Commemorative Book, Hudson and Lamas (2012), Professor Charles Fairhurst notes that on 24 May 1962, i.e., the day before the constitutional meeting of the ISRM took place in Salzburg, a reporter asked Professor Müller, “Do we know the strength of rock?”, to which Professor Müller replied, “For rock tested in the laboratory, yes. For a rock mass, no. This is what we need to determine. This is why we need an International Society for Rock Mechanics”. Also, in his Opening Address at the 1st ISRM Congress in Lisbon, Professor Müller, as the then ISRM President stated,“Many experts agree with me that discontinuity and anisotropy are the most characteristic properties of the material rock and that the properties of jointed media depend much more upon the fabrics bond of the unit rock block system than upon the rock material. Therefore any theoretical investigation of that material has to go its own ways, in the same way as the construction material of soils years ago suggested to soil mechanics its own methods, which differ greatly from the way of thinking of technical mechanics”."

Jan 1, 2015

By J. W. Merks

"Simulation is the process of designing a computerized model, of a system or procedure, for the purpose of understanding its behaviour and developing strategies to control its operation. Simulation models are rapidly becoming an effective tool for mineral processing plants. Powerful software and fast hardware are more readily available than a basic understanding of the theory of mathematical probability and applied statistics that process simulation models demand.Simple spreadsheet software can be used to develop simulation models that take into account any set of conditions at a mineral processing plant. In addition to an unbiased estimate for each variable in the set on which two-and three-product formulas are based, reliable variance estimates for all variables are required. How to estimate variances, effectively and at the lowest possible cost, and how to compute variances for simple functions such as the metal content of a quantity of ore or concentrate, or more complex functions such as the percentage recovery at a mineral processing plant, are the key to useful simulation models.IntroductionSimulation models for systems and procedures have become one of the most powerful and effective applications for computers( 2.6). Simulations are applied to a wide range of scientific and engineering disciplines. Generally, a model is designed to investigate the effects of changes in and interactions between a set of variables before a system is in operation or a procedure is implemented, by simulating weeks, months, and even years of operation, in a few minutes of computer time. Along with practical and useful applications always comeabuse and misuse. For a simulation process cannot be more reliable than the methodology that was applied to design the model, to estimate variables and variances, to check performance, and to verify validity. A mineral processing plant is a dynamic system that changes continuously as a function of time but within probabilistic constraints that can be estimated by applying statistical tools and techniques to the variables and variances that interact in the system.A model should be designed to simulate not only the set of variables but also the variance for each variable. Models in which constant variances are used to generate normally distributed random numbers, are less realistic than models in which the variances are simulated first, and then used to simulate the variables."

Jan 1, 1991

By J. Basi, J. A. Finch

ABSTRACT Testing the effects of bubble size (Db) in a Mo cleaning ?otation column at Highland Valley Copper mine indicated that increasing the proportion of small (< 1 mm) bubbles signi?cantly improved column metallurgical response, compared to typical operation. The results were a three- to four-fold Mo recovery increase and a 1 to 2% Mo (absolute) concentrate grade increase. The improvedcolumn operation produced a 4% Mo plant recovery increase. This study also showed that modelling the ?otation rate constant (k) as an inverse square function of Db was more accurate than considering k to be inversely proportional to Db.

Jan 1, 2010

By Joseph B. de Hart

Two papers recently published on the subject of mine ventilation: "The Theory of Ventilation," by Douglas Hay. and "The True Effect of Natural Ventilation in Deep Mines," by Robert Clive, form the first and second reports respectively of the committee on the Ventilation of Mines appointed by the Midland Institute of Mining Engineers. The purpose of the present paper is to draw attention to these two papers and the discussion thereon. The theory of ventilation as taught in our schools is based on Atkinson&apos;s formula, which is a variation of Chezy&apos;s formula for the flow of water in pipes. The formula depends on two assumptions : 1. That air is an incompressible fluid within the limits ordinarily encountered, and; 2. That the pressure required to produce ventilation varies as the square of the rate of flow. The Atkinson formula has been assumed to hold good over the entire range of conditions met with in mines.

Jan 1, 1924