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By Victor F. Hollister, Robert W. Hodder

"The petrology and mineralogy of porphyry copper deposits are thoroughly described in recent literature and cited as the definitive characteristics for this type of deposit. The magmatic-hydrothermal aspect of genesis is also dealt with in detail. However, descriptions of their internal structure and regional setting are not as rigorous, and the genesis of this structure is simply stated as the release of high fluid pressures in a cooling magma emplaced along large fault zones. Genetic relationships between internal structure, regional setting and the tectonic evolution of continents has been alluded to infrequently in the past, but can now be considered together within the developing concept of orogeny at the margins of drifting crustal plates.Tensional structures, on both local and regional scale, and a Triassic to Tertiary age are described for porphyry copper deposits. We contend that such structure and age are distinct and unifying characteristics for this type of deposit and are genetically related to major crustal movements. British Columbia has porphyry copper deposits contemporaneous with plutons 180 to 200 million years old and 40 to 60 million years old. The former age group correlates with early stages of the continent's westward drift, and the latter group with a change in tectonic style during late development of the Canadian Cordillera. Hence, one can in British Columbia reflect on the genesis of a deposit's structure in the broader context of tectonic evolution. Such consideration should lead to more definitive criteria for area selection in exploration."

Jan 1, 1972

By A. M. Salomon de Friedberg

With respect to impurities, HBM&S' copper smelter, located in Flin Flon, Manitoba, is in an unusual position. In addition to the usual concerns, the fact that copper and zinc production at Flin Flon is closely integrated results in the unique situation where feed to the copper smelter typically contains 7% to 8% zinc. This paper discusses the ramifications to copper smelter operations resulting from the marriage of HBM&S' metallurgical plants. Distributions of impurities (specifically Zn, Pb, Ni, As, Bi, Sb, and Cd) are presented and operating practices designed to reduce the impact of impurities on anode copper quality are detailed.

Jun 1, 1993

By A. M. Salomon de Friedberg

"With respect to impurities, HBM&S' copper smelter, located in Flin Ron, Manitoba, is in an unusual position. In addition to the usual concerns, the fact that copper and zinc production at Flin Ron is closely integrated results in the unique situation where feed to the copper smelter typically contains 7% to 8% zinc. This paper discusses the ramifications to copper smelter operations resulting from the marriage of HBM&S' metallurgical plants. Distributions of impurities (specifically Zn, Pb, Ni, As, Bi, Sb, and Cd) are presented and operating practices designed to reduce the impact of impurities on anode copper quality are detailed.IntroductionHudson Bay Mining & Smelting Co. Ltd. (HBM&s), has been operating its metallurgical complex located in Flin Flon, Manitoba, since 1930. The smelter and zinc plant were originally separate entities with respect to production. The smelting operation consisted of traditional multiple-hearth roasters, a reverberatory furnace and Peirce-Smith converters. The zinc plant also utilized multiple hearth roasters and then followed with sulphuric acid leaching, purification and electrowinning. The zinc plant also recovered cadmium from a separate purification/electrowinning circuit.The two plants operated essentially independently of each other until rising zinc levels in the copper concentrate and large stockpiles of zinc-rich leach residues prompted the construction of the fuming plant in 1949. The smelter used pulverized coal to reduce zinc oxide present in the reverb slag and then captured the resulting zinc bearing fume in the fuming plant baghouse. The fume was sent to a separate ""oxide roaster"" in the zinc plant where it was first roasted to remove halogens and then leached to recover the contained zinc. This oxide fume became a major source of feed to the zinc plant accounting for roughly one quarter of the total zinc production. Furthermore, through the smelter's treatment of sulphide leach residue, both copper and zinc recoveries were improved for the over-all complex."

Jan 1, 1993

By Vicken Aprahamian

"The Royal Canadian Mint (RCM) operates a gold and silver refining toll operation in Ottawa, Ontario, Canada. The silver refining line is a recent addition and was commissioned in 2005. One source of silver in the refinery is from gold doré which undergoes Miller chlorination before electrorefining to 99.99% cathode gold. Treatment of the Miller salt or silver-copper chloride produced consisted of a 2-stage high temperature reduction process step using soda ash prior to 2005. Copper-rich silver bars were produced and shipped offsite for further refining.The copper-rich bars could not be blended into sufficient high grade silver doré to dilute the copper and allow electrorefining in a silver nitrate medium. A new wet process was developed and commissioned to replace the high temperature reduction and allow removal of bulk copper. Thus upgraded impure silver produced was cast into anode for electrorefining to 99.9% purity silver flake. The 2005 RCM Hydromet Slag process is presented as well as its more current version. In addition, mention is made of a novel processing scenario for the introduction of Miller chlorination silver into the electrorefining circuit."

Jan 1, 2015

By E. Thune, F. Stålesen, E. O. Stensholt, O. M. Dotterud, E. E. Henriksen, P. O. Ramsdal

"The development and commercial operation of the Falconbridge chlorine leach process have been described in papers in 1985 and 1987. Since this time, various process improvements have been implemented and the capacity of the Kristiansand refinery has been increased to 85 000 t/y Ni, 40 0000 t/y Cu and 4500 t/y Co. The focus has been on continuous improvements in productivity, the use of energy and other costs. Several environmental issues have also been eliminated or reduced since 1987. IntroductionThe first nickel refining operation in Kristiansand, Norway, started in 1910 based upon raw materials from Norwegian mines. In 1929, Falconbridge Nickel mines purchased the refinery to acquire information and the patent rights to the Hybinette refining process that was practised at the small Kristiansand refinery. Falconbridge ownership has now, for more than 70 years, provided a strong base regarding raw material supply, financial resources and technical support for further expansions and major technical improvements at the refinery.The main concepts of the new chlorine leach process were developed in the laboratories from 1966 to 1969 and the process was piloted from 1970 to 1972. The main stages in the commercial plant were started in the 1975 to 1981 period. After 1981, there have been a number of process modifications, plant expansions and improvements to operating practices. The developments up to 1988 have been described in previous publications (Stensholt et al., 1986, 1988).This paper presents an overview of the process and how it is practised at Falconbridge Nikkelverk AS (FNA) today and describes some of the main changes that have been implemented since 1988. During this time, the nickel capacity has been expanded from 54 000 t/y to 85 000 t/y and the cobalt capacity from 2000 t/y to 4500 t/y. The paper describes how these expansions were achieved together with continuous improvements in operating efficiency and also gives an overview of the main environmental concerns at the refinery."

Jan 1, 2001

By J. F. Adams, V. G. Papangelakis

Chemical modelling is becoming increasingly useful in the development, analysis, design, and control of hydrometallurgical processes. The paper presents the development of reliable databases for chemical modelling of selected hydrometallurgical systems using state-of-the-art software, such as OLI. The modelling strategies are also demonstrated. The high pressure acid leaching (HP AL) of laterites, oxygen solubility in the oxidative leaching process of zinc sulfide, gypsum solubility and lead chemistry in mixed sulfate-chloride solutions are presented as case studies. This on-going work attempts to bridge the gap between theoretical research and industry needs. Computational Analysis in Hydrometallurgy 35th Annual Hydrometallurgy Meeting held in conjunction with the 44th Annual Conference of Metallurgists ofCIM Calgary, Alberta, Canada Edited by

Jan 1, 2005

By E. Michelotti, M. Cardu

This paper presents the results of a new method that has been tested to recover metallic cobalt lost by diamond beads from rock cuttings. When dimension stones are cut using diamond wire saws, the beads become worn and, before the end of their cycle life, lose a certain amount of material; this material is prevalently made up of sintered metal and diamonds. The material is then washed away, together with rock debris, in a dilute pulp. In effect, this process involves the dispersion of economically valuable, but potentially polluting, materials (such as cobalt) that are used to confer indispensable technological features to the beads. This current research aims to develop a waste-processing pilot plant (High-gradient Magnetic Separator or HGMS) to recover metallic components from the pulp by means of a suitable separation. The research\u2019s purposes are two-fold: a. to remove the polluting components from the rock debris before their disposal and b. to start a recycling process of the valuable metals.

Jan 1, 2010

By T. H. Etsell, P. Kerr

Over the past 50 years, there have been a number of geological, mineralogical and metallurgical studies carried out on the Clear Hills ironstone deposits in northern Alberta, Canada. Due to the low grade and complex mineralogy, previous metallurgical studies have achieved limited success. After rejecting some of the more ‘conventional’ techniques for iron ore beneficiation, the authors chose to investigate the grain enlargement/iron segregation process for the beneficiation of the Clear Hills ironstone. The segregation reactions for iron have not been explored in as much detail as they have for copper and nickel. Iron segregation roasting involves the addition of a carbonaceous reductant and a chloride transport agent to an iron oxide ore, and heating the mixture to an appropriate temperature. The benefit of this process is that it allows ores in which the value minerals are intimately associated with gangue minerals to be processed in circumstances where conventional iron ore processing techniques are not suitable or capable of upgrading the material. As iron is one of the few elements that can be transported through this process, a clean high purity metallic concentrate can be achieved.Through the use of crucible testing followed by Davis tube magnetic separation, scanning electron microscopy, X-ray diffraction and atomic absorption spectroscopy analysis, characterization of the reaction products has been made with an improved understanding of the reaction mechanism.

Jan 1, 2015

By J. E. Nesset

Significant progress has been made over the past few years on characterizing and understanding the hydrodynamic properties of frothers and collectors and their effect on flotation performance. This new understanding of the relationship between chemistry and hydrodynamics has dramatic implications for how flotation circuits should be controlled and optimized. Previous work has shown that choosing a frother of the right 'strength' is critical to the optimization process, and the work and discussion presented here serve to strengthen the argument. In addition, we know that collector chemistry may also influence hydrodynamic properties and needs to be taken into consideration. To achieve the desired outcome, the overall system of reagents and operating parameters must be considered. This paper describes and discusses some of the findings from recent research on frother and collector chemistry effects (on hydrodynamics), and how this knowledge can be used to improve flotation performance. Examples from plant experience are discussed.

Jan 1, 2009

By P. K. Kaiser, C. D. Martin, F. Amann

"This article focuses on the uniaxial compressive strength (UCS) of homogeneous and heterogeneous rocks. Critical factors impacting the UCS of rocks are reviewed and then separate assessments of UCS data from homogeneous and heterogeneous rocks are presented. The variability (coefficient of variation) of UCS test results for homogeneous rocks is found to be generally <25% while for heterogeneous rocks the variability is >35%. Failure mode variation is found to be the cause of the variability of UCS test results in heterogeneous rocks. Empirical engineering design methods that use UCS as an input parameter are discussed and suggestions are provided for selecting appropriate UCS values.INTRODUCTIONThe UCS is one of the most commonly used rock engineering parameters whether for rock mass classification or for strength determination. The mean UCS and its variability are often assumed to represent a reliable rock material property. For the reasons discussed in this article, UCS is rarely representative of the intact rock UCS. The UCS test simply records the collapse load during uniaxial loading of a cylindrical specimen. As suggested by many, the UCS is an index rather than a unique engineering parameter. The UCS is thus a proxy for rock strength which depends on the loading rate (e.g., Bieniawski 1967), specimen geometry (e.g., Hudson et al., 1971), specimen size (e.g., Bieniawski 1968), and many other factors. Furthermore, the UCS is not the same as the Hoek-Brown strength criterion parameter sci.There are differences in opinion on what is commonly considered to be ‘intact rock’. When sampling ‘intact’ pieces of core from drillholes crossing blocks of rock bound by block forming discontinuities, samples will be ‘intact’ but some samples will be veined, others will be damaged, and others will be neither. According to Hoek (1983), intact rock pieces are “the unfractured blocks occurring between structural discontinuities in a typical rock mass” and the sci parameter for intact rock is determined using the fitting procedure proposed by Hoek and Brown (1997) based on the data requirements outlined by Hoek (1983). Studies (e.g., Bewick and Kaiser 2014; Kaiser and Kim 2014) have shown that independently determined UCS and sci values for the same rock type are not equivalent. Thus, UCS data cannot be used as a replacement for sci."

Jan 1, 2015

By Dharmendr Kumar, Pradip, Sivakumar Subramanian, Beena Rai, Venugopal Tammishetti

The separation efficiency in a mineral processing plant is generally assessed and reported in terms of elemental assays constituting the minerals of interest. However, different minerals comprising of same elements behave differently under similar process conditions. Thus, it is imperative to track the mineral composition thank elemental composition of different streams in a processing plant. The availability of automated mineral analyzers such as QEMSCAN and TESCAN in recent times has made it possible. However, due to the high cost and expertise required, their adaptation in day to day monitoring of operations is not yet a common place. X-ray diffraction (XRD) profile fitting (Rietveld Refinement) is another technique which can provide estimates of mineral proportions in a sample. The results of Rietveld Refinement however are affected by coating of fines on coarse particles, method of sample preparation, particle size distribution of sample, elemental substitution in mineral crystal lattice. In the present work, we propose a simple and efficient method for quantitative estimation of minerals in iron ores using elemental assays and thermo-gravimetry analysis data. The minerals (hematite, goethite, gibbsite, kaolin and quartz) are identified using powder XRD analysis. It is also observed that goethite contains Al substitution in the crystal lattice. The samples were analyzed for %Fe, %Al2O3 and %Silica using chemical analysis. The measured Loss on Ignition (LOI) in the sample is contributed from goethite, gibbsite and kaolinite phases. LOI from gibbsite and goethite occur in temperature range 250–350°C and LOI from kaolinite occur in temperature range 400–700°C. According, LOI are determined in two different temperature ranges that are 100–400°C and 400–850°C. We have used the data to successfully determine the mineral compositions of iron ore samples. We have also employed a data reconciliation algorithm on the calculated data for further improvement and consistency of our results. Our method is very convenient for quick estimation of mineral proportions in a sample. The proposed method can also be used for quantitative phase estimation in bauxite ores and red muds.

Jan 1, 2016

By F. Chiesa

Experimental results on thin and thick castings poured in aluminum A356 and magnesium AZ91E by the low pressure permanent mold process have been compared to the result of filling simulations for thin and thick castings. If the results of modeling is reliable when the liquid remains above the liquidus temperature, this is no longer the case when partial solidification occurs. The visco-elastic behavior of a partially solidified liquid is difficult to put into equation as it depends on the amount of shear it has been been subjected to. Attempts to predict misruns with a commercial software has been proven to be very difficult if not impossible; divergence of the numerical solution has been observed unless prohibitively long computing times are used. In order to overcome these difficulties from a practical standpoint, a simple method is proposed which consists in tracking the temperature of the advancing liquid metal front so as to make sure it will always be above so-called `Misrun Critical Temperature&apos; (MCT) determined experimentally for thin and thick aluminum A356 and magnesium AZ91E castings. If the liquid metal front falls below this temperature, a cold-shut or misrun is likely to happen at this location. The values of MCT for thin and thick in aluminum A356 and magnesium AZ91E were determined experimentally on misrun castings of extreme geometries (a thin 2.5 mm wall cover and a 6mm to 25 mm thick bell housing). MCT was found to be lower for magnesium AZ91E and for the thicker castings.

Jan 1, 2011

By J. S. De Lury

The metalliferous areas of Manitoba have been described in more or less detail. Since the descriptions were written some new prospects have come to light and considerable mining development has taken place in two or three localities. No attempt will be made in this paper to give an account of recent activities or to describe the several areas in detail. In a general way, geological conditions are similar in all metalliferous areas of the province, a similarity that invites a discussion of the prospects as a whole, the features that are common to all deposits and the reasons for their uniformity. Modern theories of metallogenesis have a direct bearing on such a discussion and an effort will be made to show their application.

Jan 1, 1925

By C. Díaz, M. Barati

Prof. Torstein Utigard&apos;s untimely death, in the spring of 2012, put an abrupt end to a meritorious career in the field of high temperature chemical process metallurgy. As an academic in the Department of Materials Science and Engineering of the University of Toronto, Torstein made solid contributions to the advancement of knowledge pertaining to production and refining of both nonferrous and light metals, and to the development of inquisitive and innovative young people in extractive metallurgy. In this profile, the authors highlight aspects of Torstein&apos;s rich personality and of his contributions to his field of expertise.

Jan 1, 2015

By D. Michaud, C. Bazin, S. Lévesque, L. Pérez-Barnuevo, H. Longuepée

In recent years, with the emergence of Geometallurgy, a great effort has been made to characterize ore resources as early and accurately as possible, to allow better design and a more efficient operation of mineral processing circuits. In this context, core logging plays an important role, since drill cores provide the first insight into the ore characteristics. However, to satisfy geometallurgical requirements, traditional core logging does not suffice. New tools and methodologies need to be developed for the automation of core logging and the acquisition of mineralogical data better related to mineral processing performances. In this paper, a methodology for the geometallurgical characterization of drill cores is proposed, based on the drill core textural patterns. Textural pattern is defined here as the macroscopic spatial arrangement of minerals. The Mont-Wright iron ore deposit (Quebec, Canada) is used as a case study. The first part of this work aimed at analyzing the potential link between the iron ores textural patterns observed in drill cores and their response to ore processing, namely comminution and concentration. Preliminary results show similar performances in terms of energy consumption and heavy liquid separation for samples showing the same textural pattern. In the second part, this work seeks to develop a methodology for the automated identification of drill core textural patterns by the application of digital image analysis and discriminant function analysis. The results obtained show that this methodology is able to discriminate between the textural patterns identified at Mont-Wright with a good rate of success. Therefore, this work lays the foundation for the development of a new drill core characterization tool, which would allow for the early prediction of the iron ore behaviour during mineral processing through the identification of drill core textural patterns.

Jan 1, 2016

By G. P. Gu, B. Fang, R. W. Revie, M. Elboujdaini

Stress-corrosion cracking (SCC) tests were conducted in the near-neutral pH standard solution, NS4, and in an actual soil solution, using four-point bending at high a stress ratio and low frequency conditions very similar to those of operational pipelines. Pitting incubation appeared first and then pitting initiated and grew in both solutions although there were many more pits on the specimen tested in soil purged with 5% CO2 + 95% N2 than in the specimen tested in NS4 solution purged with the same gas. These observations show that samples in soil solution are more susceptible to pitting than those in NS4 solution. When the pit reached a critical size, the increased stress concentration around the pits, resulted in the transition to a crack.

Jan 1, 2005

By H. Ranjbar

The Darrehzar porphyry Cu deposit is situated in the Urumieh-Dokhtar magmatic suite of Central Iran. The REE and trace element data suggest that the deposit lies within a continental margin setting. Phyllic and propylitic alteration are pervasive in the area but potassic and argillicalteration are not readily recognized on the surface. This is possibly the result of super gene weathering of the surface rocks or because of an intense phyllic overprint. Poor soil development and abundant outcrop make the area suitable for a case study of lithogeochemical exploration technique for Cu deposits. A total of 262 rock samples was collected over the area and analyzed for 15 elements. The geochemical data cor-relate with the mineralogical composition of the rocks with the phyllic zone being marked by high-er concentrations of Si, Al, K, and by a high sericitization index while Ca, Mg, Sr, total Fe and Mn are more abundant in the propylitic zone. The lithogeochemical study indicates a metal zonation from a Cu + Mo-rich core to a Zn + Pb ± Ag-rich outer zone. Principal component analysis is useful for separating element associations, which in turn reflect the alteration halos. Principal components 1 and 2 depict alteration zoning, where-as 3 shows an association of Cu and Mo, that roughly defines the mineralized area.

Jan 1, 1997

Mineral resource development activities impact the health and well-being of many people, from workers, to families and surrounding communities. In the decade up to 2010, mining revenues increased from 6% to 14% of Australian GDP, and minerals contributed 55% of total exports, with a growth in mining employment from 1% to 1.7% of the national workforce (Connolly and Orsmund, 2011). The growth in Australia?s minerals operations is mostly located in remote areas, or in rural communities with a limited population. As a result, operations have increasingly implemented long distance commuting (LDC) programs, often called ?fly-in, fly-out? (FIFO) and ?drive-in, drive-out? (DIDO), as a staffing strategy to meet rapid industry growth in locations with limited local populations. The rapid expansion of the minerals industry has resulted in considerable public debate about the benefits and costs to all sectors of Australian society. In response to the concerns of constituencies from many parts of Australia, the Minister for Regional Australia, Regional Development and Local Government, The Hon Simon Crean MP, asked the House Standing Committee on Regional Australia on Tuesday 23 August 2011 to inquire into and report on the use of ?fly-in, fly-out? (FIFO) and ?drive-in, drive-out? (DIDO) workforce practices in Regional Australia. The recently published report highlights the national interest and the diverse opinions about this practice in Australia. Resource extraction companies have developed several options to meet the accommodation requirements of their long distance commuting workforce. In this paper, initial results are reported from an ongoing survey of FIFO (and other non-residential) resource industry workers (n = 286) in the Australian resource extraction industries. The purpose of this study was to better understand how accommodation arrangements may impact on the health, wellbeing and job satisfaction of non-resident workers; and to attempt to find a relationship between different accommodation variables and workforce wellbeing and retention. In doing this it investigates evidence for the linkage between accommodation factors, hours of work, health, well-being, job satisfaction and job retention in the LDC work force.

Aug 1, 2013

By Jing Chai

The Cenozoic unconsolidated strata with the thickness of 100 to 240m in the east area of China are composed of clay, sandy clay and hardpan, etc. Numerous shafts of the coal mines in these areas have been damaged to various degrees since 1987, with the main reason for this being the subsidence of the super-thick unconsolidated strata. To prevent the continuing settlement deformation of unconsolidated strata caused by groundwater removal, long-term water injection through multiple boreholes controlled the settlement deformation of unconsolidated strata. A new type of fiber Bragg grating (FBG) sensing system was successfully used for real-time strain monitoring of the unconsolidated strata during water injection at a coal mine in China. A mathematical model for the compression settlement induced strain calculation is proposed which can assist understanding of the effect of water injection on the ground. With the increase in water injection, the unconsolidated strata compressed state was improved by the transition of the stress state from compressive to tensile stress. The wavelength change of fiber Bragg grating sensors corresponded with the trend of the water level in the same strata. Engineering practice indicates that these sensors can normally, safely and reliably survive conditions associated with hydrous unconsolidated strata. The FBG sensing can be used for continuous lifetime monitoring of the system, starting with real-time monitoring during low-pressure water injection process of multi-borehole. The results will give important guidance for water injection and mastering stratum subsidence.

Aug 1, 2013

By M. B. McClenaghan

"Abstract- The Ontario Geological Survey completed a regional till sampling project between 1984 and 1988 in the Black River Matheson (BRiM) area of northeastern Ontario. The project was designed to aid mineral exploration in the area by documenting the Quatemary stratigraphy and by providing a database of till geochemistry. This paper summarizes the results from the sonic overburden drilling component of the BRiM project carried out in areas of thick drift (> 5 m). Results from till sampling in areas of thinner drift (<5 m) have been presented in a separate paper. Approximately 1100 till samples were collected from 225 sonic drill holes. For each sample, the non-magnetic heavy mineral (> 3.3 S.G.) and fine (-250 mesh) till fractions were analyzed geochemically and visible gold grains were recovered by panning.Gold and other multielement geochemical data were plotted using proportional symbols to high­ light anomalous areas and to demonstrate how to evaluate and interpret a very large geochemical dataset. Thresholds for identifying anomalous concentrations of Au in till samples, defined using the 95th percentile, are 1500 ppb and 12 ppb for the heavy mineral and fine fractions, respectively. The heavy mineral fraction of older tills and to a lesser extent, Matheson Till, display a number of significant gold anomalies in the study area, which in a few cases, are associated with base metal anomalies. The vertical position of gold anomalies in Matheson and older tills varies from directly on bedrock to several meters above the bedrock surface and can provide information of relative ice transport distances."

Jan 1, 1994