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By Christiaan Zeilstra, Jan van der Stel, Koen Meijer, Gerard Louwerse, Tim Peeters

The steel industry is producing about 5% of the world wide CO2 emission. Therefore the European steel industry has defined a research program to reduce the CO2 emission by 50% per ton: ULCOS. Since its start in 2004 ULCOS has identified four technologies for further development. Two of these technologies which produce liquid hot metal are discussed. The ULCOS blast furnace is based on recycling of decarbonated topgas and the capture and storage of CO2. The concept has been demonstrated during three campaigns at LKAB EBF in Luleå, Sweden. The smelting reduction process HIsarna is a combination of the cyclone-technology and Hismelt. The process has been demonstrated successfully in four campaigns at a pilot installation on the IJmuiden steelmaking site.

Jan 1, 2015

By S Romanchuk, V N. Macvkiw, D. J. I. Evans

The paper describes the processes developed and piloted by Sherritt Gordon Mines Limited for recovering copper, in the form of specification copper powders, from Lynn Lake sulphidic copper concentrates and Fort Saskatchewan Refinery by-product copper sulphides. The process includes ammonia pressure leaching and hydrogen reduction from solution. Nickel and cobalt present in the con-centrates dissolve in the leach solution and a method was developed for separating these metals from the cop-per. Methods are described for con-trolling the physical properties of the copper powder produced in the reduction vessel. The chemistry of the process is briefly discussed and the effects of some of the more important process variables are described. SHERRITT Gordon Mines Limited have developed and proven on a pilot plant scale, a process (I) for the production of copper powder

Jan 1, 1961

By A. Himsley

This paper presents a review of the existing ion exchange resin systems for treating unclarified pregnant liquor, with particular reference to uranium extraction. A new concept of a truly continuous ion exchange system is described and operating details are given,of a 0.6.-m (24 in.) diameter pilot plant treating unclarified acid leach liquor.

Jan 1, 1977

Despite the fact that mined minerals and gemstones have allowed human beings to continuously improve their standard of living throughout the ages, mining has also been implicated in violent conflict for two principle reasons. The first is that mineral resources have been used or traded to conduct or finance violent conflict from small to large scales. The second is the substantial social, economic and environmental changes that occur in a community or a region as a result of mining activity which can either precipitate or re-awaken latent conflict. A modern complication of mining-related violent conflict is the trend for activists, international NGOs and intergovernmental organisations (e.g. the United Nations) to regard any human consequences of resource extraction in terms of Human Rights violations. Acknowledging but not labouring the Human Rights implications of mining-related violent conflict, this paper explores whether or not there is a relationship between the actual or perceived value of mineral resources and the level of violence that occurs in mining-related conflicts. Key to the investigation is a mapping exercise of mining related conflict from 2005 ? 2012: to see where mining related conflict is happening; to identify precipitant causes of mining related conflict; and, to discover what correlation ? if any ? there might be in the degree of violence and the value of the mineral(s) implicated. Findings of the analysis are presented in this conference paper.

Aug 1, 2013

By C P. Gravenor

In 1953, a deposit of sedimentary oolitic iron ore was discovered in the Clear Hills area of northwestern Alberta. Since that time, detailed drilling has outlined reserves in excess of 200 million tons of ore grading 30 to 35 per cent iron. Attempts to physically beneficiate the ore to meet blast furnace or direct reduction feed specifications have been, in general, unsuccessful. In 1960, Premier Steel Mills Limited and the Research Council of Alberta jointly sponsored a pilot-plant test at the R-N Corporation at Birmingham, Alabama. About 5,000 tons of ore were treated, and briquettes containing 90 per cent Fe were produced, with 83 per cent recovery. At the same time that the R-N tests were being made, the Research Council initiated a program to produce high-purity powders by chemical methods. Several purification techniques were investigated; hydrochloric acid dissolution of reduced ore was finally adopted. Briefly, the steps involved in this acid process are as follow

Jan 1, 1964

By B. N. Nandi

This paper is a study of the application of the science of coal petrology to the use of coal in the iron and steel industry. The petrography of coal is given the most attention, with some mention of coal palynology. The history of the petrographical analysis of coal is first out-lined, with a description of the various coal entities, and then the apparatus and experimental techniques employed for coal evaluation are discussed. The coke stability factor and the relation of coke strength to petrographical data are also covered, and some space is given to the new science of coke microscopy, in particular its use in following the oxidation of coals.

Jan 1, 1966

By M. Honarmand, Z. Moezifar, H. Ranjbar

Abstract - The Sar Cheshmeh area covers an area of 640 km2, and is located in the southern part of the Iranian Volcanic-Sedimentary Belt. ETM+ images have been used for alteration mapping. The Crosta method was found useful for enhancing exposed areas containing hydroxyl and iron oxide minerals. However, field checking has shown that this method is not able to identify all the known areas of hydrothermal alteration. Many of these altered areas are also not clearly resolved in the geophysical data. In order to improve resolution of such areas, integration of remote sensing and geophysical data may be helpful. The Darrehzar Cu deposit was chosen as a control area. The data have been divided into two sets: explanatory and target variables. The explanatory data are Landsat hydroxyl and iron oxide images and airborne geophysical data (K, U, and Th total counts, and total magnetics). The target variables are rock geochemistry and ground geophysics. Data analysis and integration of geophysical and remote sensing data were performed using directed principal components. This technique is found to be useful for the delineation of hydrothermally altered areas with more confidence.

Jan 1, 2002

By Bruce C. Smart

"Very little attention was given to the regulation of uranium mills by the Atomic Energy Control Board prior to 1974. The ore grade treated by Canadian mills in the past was in the order of 0.08 - 0.3% U and it was not difficult to keep the exposure of workers well below regulatory limits. Furthermore, uranium milling has also been substantially free of occupational illness because environmental control has been generally satisfactory (l).The discovery of higher grade ore bodies in Canada has resulted in higher radiation levels in one mill and this has partly contributed to a need for increased radiation monitoring in the mill. In addition, as greater insight is gained on the effects of radiation, the implementation of the ALARA principle is being stressed at all mills.The concept of ALARA was emphasized by the ICRP (International Committee for Radiological Protection) in 1977 and stands for '""as low as reasonably achievable'"". It is based on the premise that no proven threshold for potential effects of radiation exists and that the actual individual exposure should therefore be kept as far below the regulatory limit as possible, economic and social factors being taken into account."

Jan 1, 1982

By W. R. Bacon

"MAGNETITE HAS BEEN found in many .parts of the coastal area of British Columbia, but the more important deposits are on Vancouver Island and Texada Island. The locations of these deposits are shown on Figure 1.Interest in the magnetite deposits dates back to the 1870s, when land was acquired on the southwest coast of Texada Island by the Puget Sound Iron Company. This ground included the Prescott, Paxton, and Lake deposits. During the years 1885 to 1903, and 1908, 28,898 tons of magnetite ore was shipped to the company's blast-furnace plant at Irondale, Washington, U.S.A. This production was almost entirely from the Prescott open-pits.In the years following the Texada Island discoveries, other magnetite deposits were found in the coastal area, and various plans were proposed to utilize the local ores in the establishment of a steel industry in the Pacific Northwest. None was carried to fruition but, in 1951, open-pit mining was begun at Iron Hill, Vancouver Island, to furnish iron concentrates for steel mills in Japan. In 1952 mining of the Texada deposits was resumed to supply the same market. Production figures for these recent operations are as follows:"

Jan 1, 1949

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

Agenda ?The Context ?The Challenge ?The Solution ?Benefits and lessons learnt from pilots ?Next Steps The Context ?Facilitate management decision making process by supporting the development of value/risk based business cases. ?Large scale investments by extractive industries are expected tobring broad-based benefits to local communities (e.g.: health, education, jobs, infrastructure) ?Investors continue to expect the demonstration of social performance?Specific interventions bring direct value to companies (e.g. skills development) ?Social Investments are key to protecting a company?s license to operate ?Quantifying the value of these investments and planning accordingly, however, has long posed a challenge for the extractive industries and community development practitioners

May 1, 2011

By G. P. Cooper

A comprehensive computational heap leach model was used to evaluate options for operating a chalcocite-ore heap leach process. The stockpile leach model is based on the computational fluid dynamic software framework PHYSICA+ and incorporates various physical and chemical phenomena to simulate fluid transport, mineral reaction kinetics, bacterial effects, and heat, energy and acid balances for the overall leach process. The leach model is calibrated against small-scale column leach tests, and simulation results are validated against closely controlled column pilot-scale tests. For a given set of ore conditions, the effects of raffinate irrigation rate are examined. Several options for pulse leaching were investigated, and the effects on copper recovery and pregnant leach solution (PLS) grade are described. Model simulations indicated that pulse leaching could be used to control copper grade of the PLS. Finally, an analysis of inventory issues is presented for various lift heights including multi-lift simulations to examine potential operating options. U sing irrigation rate, raffinate copper grade, and lift height as variables in a factorial design of experiments, the simulations showed that raffinate copper grade is the main factor that affects the soluble copper inventory grade.

Jan 1, 2007

By M. Al-Hilal, G. Rajja, A. Al-Ali, Y. Jubeli

Abstract -A radiometric survey was carried out over clastic sediments in the immediate vicinity of some phosphatic sediments of Cretaceous age in the Wadi Qasser Al-Hallabat basin of central Syria. The objective was to explore for uranium and to define its dispersion pattern. This was based on ground radiometric surveys and geological studies. All ground surveys (using radon emanometry, track etching, gamma-ray survey and geochemistry) gave similar results, outlining the locations of the radioactive phosphatic formations in the basin, and indicating the dispersion pattern of uranium in the clastic sediments in the surrounding area. The dispersal of uranium from upper Cretaceous phosphatic formation occurs by mechanical weathering and chemical leaching by oxidizing surface waters. A rough estimate is that about one-third of the original uranium content of the Cretaceous sediments has been dispersed. Mechanical erosion is responsible for the main part of this released uranium, which now occurs in Recent sediments. However, the occurrences of spotty secondary U mineralization indicates that another small part of the available uranium must have been chemically leached out by the prevailing oxidizing waters, forming minor surficial minerals.

Jan 1, 1998

By A-A. Bogno, M. Rappaz, J. Valloton, H. Henein

"Rapid solidification of Al-Cu droplets of eutectic composition was carried out using Impulse Atomization in an argon atmosphere, to study the microstructures forming at different cooling rates and undercoolings. Two distinct morphologies were observed within the investigated Al-33wt%Cu droplets microstructures: (i) A regular lamellar morphology and (ii) an undulated morphology. The volume fraction of each type of morphology was measured as a function of the droplet size and the nucleation undercooling was deduced using the hypercooling limit equation. The scale of the microstructures was determined through measurements of inter-lamellar spacing across and along the growth direction. Growth velocity and undercooling were deduced using Jackson and Hunt (1966) eutectic growth theory. Finally, mechanical properties were estimated through micro-hardness analysis using a Vickers hardness tester, revealing exceptional properties for an aluminum-copper alloy. Indeed, the hardness values, increasing with growth rate and undercooling, were 3 times higher than the values obtained in hypo-eutectic Al-Cu alloys.INTRODUCTION Eutectic alloys are very attractive due to their good fluidity allowing ready shaping of parts in casting processes as well as in thermal spray deposition. In addition, they yield microstructures with high mechanical properties, by the virtue of their scale/size which is defined by the solidification parameters and the thermodynamic and thermophysical properties of the given alloy. Therefore, it is important to understand the relationship between the microstructures and the solidification parameters of eutectic alloys in order to control their solidification path and mechanical properties. The latter could be improved by either adding an appropriate strengthening component to a base eutectic material (Böyük, MaraslI, Kaya, ÇadIrlI, & Keslioglu, 2009) or by refining the microstructures for more effective dislocation pinning (Campbell & Campbell, 2003). Tailoring the microstructure can also be beneficial to chemical (Freitas, Osório, Spinelli, & Garcia, 2014; Osório, Freire, Caram, & Garcia, 2012) or electrical (Kaya, 2012) properties of the material. Eutectic-type microstructures, usually formed from liquid (eutectic transformation) or solid (eutectoid transformation), are made up of two or more different phases, generally of lamellar or fibrous (rod like) morphologies (Kurz & Fisher, 1998). In general, a binary eutectic structure can be regular (when both phases are non-faceted) or irregular (one of the two phases is faceted), the two solid phases having roughly the composition of the liquid from which they are formed."

Jan 1, 2017

By J. Zhou1

"The extractive metallurgy of gold ores is largely driven by their grade and mineralogy. The concentration of gold in the crust is extremely low and highly variable, resulting ore variability in many gold and copper-gold deposits. More importantly, gold in an ore may occur in two or three forms (i.e. microscopic gold, submicroscopic gold and surface gold), making gold ore processing extremely challenging. Geometallurgy is a technique to document variability within an orebody and quantify and evaluate the impact of many factors including geology and mineralogy on grinding, flotation, leaching and metal recovery processes. The objective of gold geometallurgy is to reduce and minimize the technical risk in project evaluation, plant design, mine planning and production forecasting through geometallurgical modelling, representative sampling and subsequent systematic mineralogical and metallurgical testwork. Gold deportment study is a powerful tool in characterization of various gold ores. Effective and quantitative gold deportment results are critical and useful for predicting gold recovery and building geometallurgical models of gold ores. This paper provides an overview of geometallurgy fundamentals and applications in gold processing, with a focus being on the ore characterization and gold deportment study.INTRODUCTION Geometallurgy is an inter-disciplinary approach which links the geological, geochemical and mineralogical characteristics to the metallurgical performance of an orebody. Combined with mine planning, it has been used in scoping, prefeasibility and feasibility studies, process design and optimization of gold, copper-gold, copper-moly, nickel and iron projects among others (Williams & Richardson, 2004; Dobby, Bennett, Bulled, & Kosick, 2004; Bulled, 2007; Bulled, Leriche, Blake, Thompson, & Wilkie, 2009; Kormos, Sliwinski, Oliveira, & Hill, 2013; Muinonen, Sciortino, Korczak, & St-Jean, 2013; Leichliter & Larson, 2013; Leichliter, Jahoda, & Montoya, 2013; Hatton & Hatfield, 2013; Baumgartner et al., 2011, 2013; Hoal, Woodhead, & Smith, 2013; Zhou, 2013). The goal of a gold or copper-gold geometallurgical program is to characterize and understand the metallurgical variability of an orebody, such as comminution, gravity, flotation and cyanidation parameters and metal recoveries, and to build a geomet model which can be used to assist in mine planning and to predict the plant performance. In any geometallurgical program, representative sampling is the key to ensure the results of a geometallurgical study will reflect future performance once the plant is commissioned. Geometallurgy compliments, but does not replace, the traditional mineralogical and metallurgical approach during the development and operation of a gold or copper-gold project. Geometallurgy is a methodology for testwork design and a framework for mine planning. The first part of this paper provides an overview of geometallurgy fundamentals and application in gold ore processing."

Jan 1, 2017

By Jirí Faltus

The paper deals with studying the impact of structural properties and anodizing of surface on the corrosion properties of extruded rods from commercial aluminium alloys: AA6082, AA6262, AA6012, AA2007 and new lead-free aluminium alloys AA6023, AA2015 and AA2111B. Samples were exposed to the corrosive atmosphere NSS, AASS in the chamber by EN ISO 9227. Surface of samples were either in the original state or anodizing by selected mode. The depth of corrosion attack and the form of corrosion attack are evaluated depending on the type of alloy, the metallurgical condition and surface treatment of the samples.

Jan 1, 2015

By R. D. Browns

In his Budget Speech on March 31, 1 977, the Honourable Donald S. Macdonald expressed concern about the financing of investments through new equity issues. He mentioned the need to render more attractive participation in the equity market by investors in all in come brackets. One of the measures introduced in the budget to accomplish this goal is the proposal to increase the dividend gross-up and tax credit in respect of most dividends received by an individual from Canadian companies. The following comments and tables serve to illustrate the impact of this particular proposal.

Jan 1, 1977

By R. L. Bruening, J. B. Dale, N. E. Izatt, S. R. Izatt

IBC Advanced Technologies' Molecular Recognition Technology (MRT) SuperLig® products selectively and rapidly bind with target metal ions to remove them from solution. The MRT process can produce a high purity separation product of maximum added value at low cost. This paper discusses applications for MRT in the gold industry, including recovery of gold and silver as well as metal contaminants from various process and recycle streams.

Jan 1, 2011

By W. H. MacLean, S. Liaghat

The Key Tuffite is a thick (0.3 m to 6 m) and laterally extensive (-10 km) cherty, sulfide-bearing tuff unit in Archean greenstones in the Matagami mining district in northwestern Quebec. It lies at the contact of the Watson Lake Group and overlying Wabassee Group volcanic rocks, and is host to major Zn-Cu volcanogenic massive sulfide deposits. The tuff component is highly altered and its volcanic precursors are not identifiable by petrographic means. The tuff is mixed with a volcanic exhalative component comprising chert, carbonate and sulfides (pyrite, pyrrhotite, and minor sphalerite and chalcopyrite). The normative mineral composition of the Key Tuffite is 33% quartz, 28% sulfides, 16% sericite, 8070 carbonate, 6% chlorite and 9% other minerals. In the vicinity of the Bell Allard and Orchan mines, the precursor tuff components are identified using immobile major and trace elements, as Watson Lake tholeiitic rhyolite (Zr/Y = 1.5 to 3.5, LaN/ybN = 1.7 to 2.8, SiO2 = 72.5 ± 1.2 wt %, and Wabassee calc-alkaline andesite (Zr/Y = 9, LaN/YbN= 4 to 8, SiO2 = 56% to 65%). Immobile element computation techniques were used to calculate mass additions and losses in the conversion of the tuff to the Key Tuffite. Average net amounts of FeP3 (27% total iron), Si02 (14%), Cao (8%), S and K2 (+ 2%), were added, Nap was removed (-2.8%), and MgO was over-all unchanged. Total net mass change was +63%, which comprises mainly exhalative additions, but also includes changes owing to hydrothermal alteration of the tuff component.

Jan 1, 1992

By G. Granata, C. Tokoro, M. Matsuoka, K. Horiuchi

"Given the high demand of copper and the lack of new high-grade deposits, low grade copper ores containing copper oxides and refractory sulfides need to be processed as well. However, in order to recover copper from refractory copper ores, the leaching performances should be improved. In this study, we investigated the effect of the mechanical activation in the leaching of copper from covellite. The influence of a mechanical treatment by planetary ball milling on leaching rate in sulfuric leaching media was evaluated by using X-ray diffraction (XRD), mineral liberation analysis (MLA) and X-ray absorption fine structure (XAFS). Results showed a significant increase in copper leaching from around 50%up to 100% along with an improvement of the leaching kinetics when using planetary ball milling. XRD spectra showed the disappearance of the covellite peak from (101) face, thus suggesting the amorphization of covellite associated with the use of planetary ball milling. XAFS results showed that the coordination number of Cu changed from 6 to 3, thereby confirming the effectiveness of the mechanochemical effect.INTRODUCTIONDuring the last decades, while the copper grade in copper ores has been decreasing, the concentration of impurities such as arsenic tends to increase, thus requiring for the processing of low grade copper ores. For a suitable processing of copper minerals, hydrometallurgical processes are preferable due to the lower costs, the lower environmental impact and the easier implementation (Watling, 2006). However, for an economical recovery of copper, the leaching performances must be improved.Among the recent advancements in leaching technologies, the mechanochemical activation allows for an improvement of the leaching performances by means of high-intensity grinding(Mohammadabad et al., 2016). In the first place, the improvement is the result of the dramatic decrease of particle size, which results in an increase of the mineral surface area and the consequent enhancement of leaching kinetics. Furthermore, the intense mechanical stress due to the high-intensity grinding could induce the rupture of the crystal structure producing a decrease of crystallinity. Such changes of the mineralogical structure, also known as mechanochemical effect, can lead to more leachable mineral, thereby resulting in a greater dissolution of copper. Last but not least, whereas the mineral surface might undergo passivation during leaching, the high-intensity grinding can continuously refresh the surface of the mineral, thus exposing portions of unleached bulk mineral."

Jan 1, 2017