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By K. J. Palmer, D. A. Silva

"Evaluating resources and reserves requires the reliable modelling of geological domains and their grades. “Multiple point statistics” simulation is a relatively new geostatistical method to generate complex, high-resolution geological models by extracting high-order spatial relations from training images. A method based on combining multiple training images is developed to obtain the correct amount of large-scale continuity and short-scale variability. A calibration process matches the geological spatial variability between the final realizations and the drillhole dataset. A case study with data from the Red Dog mine, Alaska, United States, shows an appropriate reproduction of short-scale variability along boundaries between geological units.RÉSUMÉ L’évaluation des ressources et des réserves exige une modélisation fiable des domaines géologiques et de leur teneur. La simulation par « statistique multipoint » est une méthode géostatistique relativement nouvelle pour générer des modèles géologiques complexes à haute résolution par l’extraction de relations spatiales d’ordre supérieur à partir d’images d’entraînement. Une méthode basée sur la combinaison de multiples images d’entraînement est développée afin d’obtenir la bonne quantité de continuité à grande échelle et de variabilité à petite échelle. Un processus d’étalonnage fait correspondre la variabilité géologique spatiale entre les réalisations finales et l’ensemble des données de forage. Une étude de cas avec des données de la mine Red Dog, Alaska, États-Unis, montre une reproduction adéquate de la variabilité à petite échelle le long des limites entre les unités géologiques."

Jan 1, 2015

By J. R. Levin, E. J. Schelter

"We present some of our recent efforts in the development of predictive, directed oxidation chemistry of cerium(III) complexes under non-aqueous conditions. The electrochemistry of cerium(III)- alkali metal heterobimetallic aryloxide complexes is reported and compared with cerium aryloxide complexes that are kinetically stabilized by hydrogen bonding cations that span between the complexed aryloxide ligands. Comparative electrochemical measurements reveal differences between the heterobimetallic complexes and the hydrogen-bonded complexes.INTRODUCTIONThe rare earth elements comprise the lanthanides, La–Lu, and the element yttrium (Aspinall, 2001). Rare earth ores such as monazite, LnPO4, and bastnäsite, LnFCO3, typically bear mixtures of light rare earths: La–Sm while monazite, LnPO4, contains mixtures of heavy rare earths (Eu–Lu) (Cotton, 2006). Pure rare earth elements typically are isolated using a liquid-liquid separations process.(Bautista, 1995) The hydrometallurgy of these elements is a difficult problem because the separation factors between neighboring rare earths, which are predicated on the small differences in the sizes of the trivalent ions, are quite small (Cox, 1992). The element cerium, with its 4f1 electronic configuration in the trivalent state, is unique among the rare earth elements due to a relatively accessible 4f0 electronic configuration. The accessibility of the 4f0 configuration underlies the chemistry of cerium(IV), the only rare earth ion with molecular chemistry in the tetravalent oxidation state (Cotton, 2006). Cerium is trivially separated from mixtures of light rare earths by making use of its unique oxidation chemistry. In an effort to extend separations chemistry by oxidation reactions to other rare earth elements such as terbium and praseodymium, the solution electrochemistry of well-defined cerium complexes is of interest."

Jan 1, 2012

By K. Huang, L. Pan

"Darcy’s law has been used extensively to model cake filtration. It is a macroscopic model, in which particle size dominates the kinetics and cake moisture. In the present work, a capillary flow model has been developed from first principles to study the effects of microscopic parameters such as capillary radius, boundary layer slip, disjoining pressure, and surface tension that may be important for dewatering ultrafine particles. Laboratory-scale pressure filtration tests show that dewatering kinetics is strongly dependent on capillary radius, which in turn is influenced by surface hydrophobicity, surface charge, and length scales of particles. The model parameters determined from laboratory-scale filtration tests show that use of a hydrophobizing reagent can greatly improve fine particle filtration due to increased slip and decreased capillary pressure. The kinetics of dewatering kaolin clay is fastest at a pH where the layer-structured particles coagulate with a face-to-edge orientation. The capillary flow model developed in the present work may be useful for designing filters and optimizing operating conditions.INTRODUCTIONIn 2014, Canada produced 2.2 million barrels per day of crude oil from the oil sands resources in Alberta, which is expected to grow to 3.2–4.0 million barrels per day by 2030 (CAPP, 2013). One of the challenges to meeting these projections is the tailings management. At present, the industry uses ?77 km2 of the lands to construct tailings ponds. Significant amounts of the tailings disposed to the ponds are silts and clays that are slow to settle and consolidate, creating problems for reclamation. It is, therefore, the objective of the present work to develop a filtration model that may be useful for developing advanced dewatering technologies that can address the tailings management issues.Darcy’s equation is the governing law for filtration. It was derived as an empirical model by H. Darcy in 1856 while he was studying fluid flow in sand filters (Hall, 1956). Since then, many investigators derived it from first principles. It relates superficial fluid velocity to the pressure drop across a porous medium of known permeability. In filtration, the latter can be related empirically to particle size using the Kozney equation (Yoon, 2005)."

Jan 1, 2016

By V. G. Papangelakis, J. E. Dutrizac, G. Azimi

A new model capable of predicting the solubility of calcium sulphate solid phases in zinc sulphate processing solutions from 25 to 95°C was developed. The model uses the Mixed Solvent Electrolyte (MSE) model of the OLI systems software to calculate the mean activity coefficients of the electrolyte species. The model was tested using recently developed experimental measurements. It was shown to predict accurately the solubility behaviour of calcium sulphate in multi-component zinc processing solutions containing ZnSO4, H2SO4, MgSO4, MnSO4, Fe2(SO4)3, Na2SO4 and (NH4)2SO4. The model can also explain the complex effect of coexisting metal sulphates on the solubility of the CaSO4 phases. The model is a practical tool for assessing the process chemistry of a wide variety of complex aqueous processing streams.

Jan 1, 2008

By Caroline B. Chapleau, Mélanie Proulx, Claude Bazin, Gaétan Lavoie

"Quebec Cartier Mining operates a pelletizing plant in Port-Cartier, QC. Grinding, agglomeration and pellets induration are the three main steps in the preparation of iron oxide pellets. In 1998, following different recommendations, the company increased the speed of one of its ball mill in order to increase the grinding efficiency of the machine. As expected, the increased speed lead to an increase of the power draught, which did not produce the expected increase of fineness of grind, neither its allows to increase the mill throughput. The change of behaviour of the mill could hardly be understood by comparison of discharge size distribution at initial and modified mill rotation speed. On the other hand, the use of the selection function from a population balance model provides an insight of the changes that occurred in the mill. This paper reviews the various steps required for the estimation of a grinding mill selection function. Results of the calibration to Quebec Cartier grinding mills show that the increase in the mill speed leads to higher rate of breakage of coarse particles, at the expenses of less efficient breakage of medium and fine size particles. In the case of the studied mill, breakage of coarse particles was probably not the critical step of the mill operation. INTRODUCTIONOre size reduction is the major energy consumption step in any mineral processing operations (Austin et al., 1984). Size reduction is required to either liberate valuable minerals from the gangue minerals in which they are imbedded, or to increase the specific surface of the ground material. Plant engineers continuously face the challenge to find grinding machines, operating conditions or grinding circuit flowsheet configurations that could improve the size reduction process at lower energy or m6dia consumption."

Jan 1, 2000

By Philip J. Guerney, S. O’ Leary, André R. Laplante

"Concentration of dense mineral phases (s.g. greater than 7) for characterisation of individual particles and mineral grains by electron microscopy is a well established technique for the detection and characterisation of valuable mineral phases. This presentation describes the type of data that can be generated when both the concentration and characterisation steps are carried to higher levels than typical. The concentration step is the gravity recoverable gold (GRG) protocol that has been used for over 100 ore samples. This protocol yields three concentrates that represent three progressive degrees of grinding and liberation. Three ore samples were subjected to the GRG protocol and three size classes of each concentrate were characterised using the mineral liberation analyser (MLA), an automated, EDX-based tool. This presentation briefly presents GRG and MLA technology, and then focuses on the results obtained: photos, images and databank, the latter used to evaluate the extent of particle liberation and particle shape.INTRODUCTIONThe practice of gravity concentration prior to characterization of mineral samples using electron beam microscopy is solidly established. Typically, a dense liquid such as tetrabromoethane (density: 2.97 g/cm3) is used to reject the light phase, typically carbonates and silicates. The heavy phase, mostly sulphides, oxides and precious metals, is then mounted in a polymer matrix and examined using beam microscopy.Both the pre-concentration and the sample preparation/examination steps have seen significant advances over the past ten years, but are not without problems. A major issue of preconcentration is that most dense liquids used are toxic, tetrabromoethane being a prime example. More recently, a dense liquid with little or no toxicity (sodium polytungstate, distributed by Sometu Inc.) has become commercially available, but its use is limited to relatively low s.g. splits around 3 g/cm3. Dense liquids are viscous, and their use is limited to particles coarser than 37 µm, although centrifuge separation can probably lower this limit to around 10 µm. Magnetogravimetric separators can achieve much higher specific density cuts, but upgrading below 100 µm or in the presence of magnetic minerals remains a problem. The use of centrifuge separators such as the 3-in Knelson Concentrator (KC MD3) or the Falcon 4-in SB (SB4) is particularly attractive since these units can easily process large masses (by laboratory standards) and achieve a cut density well above those of dense liquids."

Jan 1, 2003

By Raju S. Sagi

This paper deals primarily with the different types of drilling methods used by the Iron. Ore Company of Canada for sampling the soft and friable hematite-limonite (secondary) iron ore deposits found in the Scheferville area. The problems associated with drilling, sampling, sample handling and sample preparation. for chemical analysis of these ores are discussed. Systematic evaluation of the various drilling methods led to the selection of an integrated drilling system. This system consists of a rotary dual- tube - reverse-circulation drill, with tricone bit, polymer mud and mechanical sample splitter, The historic al development of this drilling system is described in detail, as are the equipment , sample flow and quality control checks carried out to obtain representative samples. This integrated drilling and sampling system has been used satisfactorily on a routine basis for determining the grade and tonnage of ore for the various deposits for the last five years (1972-76) in the Schefferville area.

Jan 1, 1977

By Dennis Hoffmann

"Abstract - Banded iron formation rocks associated with massive sulfide lenses in the Broken Hill Pb-Zn-Cu-Ag deposit in the Namaqualand Metamorphic Complex, South Africa , were investigated with respect to the geochemistry of manganiferous silicate-rich bands. Two common varieties of these are: amphibole- and garnet-rich iron formation bands. The results reveal that the former are enriched in Fe, Mg, Cu, Co and S. The garnet-rich bands are enriched in Mn, Ca, P, Pb and Ba with significant detrital contamination of Ti, Al, Zr, Cr, Y, V, Ni and Nd.The silicate-rich bands have compositions, in terms of, Si/Al, Si/Fe, Fe/Mn, La/Ce and Co/Zn, comparable to submarine chemical sediments which precipitated from hydrothermal fluids. The garnet­ and amphibole-rich bands are interpreted as ""evolved"" and ""immature"" hydrothermal sediments, respectively. The latter resulted from rapid precipitation after exhalation, whereas the former had a longer residence within sea water. The silicate-rich bands both exhibit increasing Mn/(Mn+ Fe) fractions, which are consistent with a variation expected from proximal to distal depositional settings. The prevalence of garnet-rich bands over amphibole-rich bands is interpreted as the result of injection of hydrothermal fluids from a single vent situated along the northwest margin of the Broken Hill deposit."

Jan 1, 1994

By Dave Stefanuto

Voisey?s Bay Project Components ? Mine/Mill Port In Labrador ? Mini Plant in Mississauga ? Demonstration Plant in Argentia ? Supply Vessel (Umiak1) ? Transshipment Facility (Quebec) ? Concentrate Handling & Transport to Sudbury/Thompson ? Cobalt Refinery Upgrade (Thompson) Project Setting ? The Project is on the traditional lands of the Labrador Inuit and the Labrador Innu ? Canadian courts have held that Aboriginal peoples in Canada possess special rights to traditional Aboriginal lands Those rights can include requiring resource developers to enter into Impacts and Benefits Agreements (IBAs) on traditional lands to set forth how lands can be used and benefits to be received by Aboriginal people

May 1, 2006

By R. Erpelding

High Pressure Grinding Rolls (HPGR) are said to be a good option in new grinding circuits. Due to their low energy consumption compared to other grinding systems such as SAG milling, there is a strong incentive to check their behaviour for certain ore types. With rising energy prices the operation will become even more beneficial in future. As published in the past, the HPGR is claimed to increase the liberation of the valuable mineral component within an ore. An investigation at the research centre of Polysius was conducted to substantiate the liberation behaviour in finish grinding operations. A pilot scale HPGR test unit (POLYCOM MAGRO) with a roll diameter of 950 mm and processing capacity of 80 t/h was used. Grinding tests were completed with a screen and a two stage drying air separation process (SEPOL). Analysis included standard screen analysis, fractional XRF and modern MLA technology. A technique was developed to oppose the amount of produced slimes (resuming bad flotation) against the positive effect of producing high mass fraction at flotation-easy sizes. The paper shows how effective the use of a dry grinding separation could be in terms of production of mass of liberated metal.

Jan 1, 2012

By M. H. Govett, G. J. S. Govett

"The current American ""energy crisis"", occurring in the midst of a global debate on the adequacy of mineral supplies to support present and projected levels of world consumption, has focused attention on Canada as a major world producer of minerals. Exports of minerals account for approximately one-third of Canadian foreign earnings; more than half of these exports are to the United States. Although the United States is a net importer of most industrially important metals, with the exception of nickel and zinc, only a small part of American mineral imports are from Canada; these imports are minerals for which geographical proximity and strategic considerations are important. In the short-term, Canada is more dependent on her exports to the U.S. than America is on imports from Canada. It is argued that Canada, far from indulging in economic nationalism to preserve her resources, should expand her exports while the markets are available."

Jan 1, 1973

By Jean Vavrek, Rob Barber

"What is CIM’s role on a planet-wide scale?That question has been coming back to the forefront of many discussions regularly in the months since we came on board as Executive Director and Vice- President International. CIM, by its name and by the nature of its history and make up, has mainly been a Canadian entity. It has been created by an act of Canadian Parliament and it is set up to work within the Canadian federal and provincial framework.Yet the name CIM is one well known and recognized for quality and professionalism worldwide. One could say that CIM has established a level of brand recognition that transcends it name and its origin. CIM has also evolved with the times, as the world has evolved and more so as the world of mining has evolved. So we stand today with a fairly large portion of our membership residing outside Canada and outside the United States. We also stand today looking back at the role CIM has played in events that we have been partners in organizing outside Canada; and for a long time CIM has provided insights into what is going on in the rest of the mining world by inviting authors and by featuring topics from around the globe.Today, Canada is still a leader in the mining industry. Canadian mining companies are involved in exploration and operations around the world. Canadian operations serve a good portion of the global demand of many metals and minerals, recently adding diamonds to the slate. Canadian expertise in various areas also makes Canada a good base for exporting a wide range of products and services around the world."

Jan 1, 2004

By Catalin Florin Petre, Elahe Ghasemian Langeroudi, Abdelaaziz Azizi, Éric Proulx, Caroline Olsen, Paul Blatter, Faïçal Larachi, Claude Gagnon

"The recovery of gold from ores is often accompanied by the release of other species in the leach solution. This state of affairs leads to depleted free cyanide levels in the slurry. Therefore, separation and quantification of these cyanicides and free cyanide at different stages of the cyanidation process as well as in waste solutions is crucial to provide mitigation tools by preventing leaching of deleterious metals for environmental considerations.COREM and the research group of Prof. Larachi have been working together on the control of gold passivation and cyanicides during cyanidation for several years. Previously, a first capillary electrophoresis (CE) protocol for the speciation of sulfur and cyanicides (SCN-, Cu, Fe) during cyanidation of gold complex sulfide ores was developed and validated for assessing industrial process water.The separation of zinc cyanide complexes used to be confronted with a number of difficulties due to the weak and/or undetectable cyanocomplexes in formally available CE protocols. Moreover, according to our knowledge, no direct CE protocol exists to separate free cyanide. Therefore, a new study aimed at developing a second CE protocol for the detection and quantification of cyanide complexes of zinc and nickel as well as of free cyanide in the cyanidation process water.To achieve this goal, six common carrier electrolytes such as pyridine, trimellitic acid, 4-methylbenzylamine, sodium chromate, phthalic acid and tris base were studied, using an indirect UV detection method. The best results were obtained using sodium chromate for which all ions were successfully separated and quantified. In addition, the effect of electric field strength, injection volume, electro-osmotic flow (EOF) modifier and background electrolyte (BGE) concentration were examined, while peak height, peak area and noise were considered for optimization.As a result, the new protocol is expected to complete the initial CE protocol by detecting cyanide complexes of zinc and nickel as well as free cyanide. Moreover, analytical determination of free cyanide in the presence of weak cyanide complexes achieved by the new protocol was also compared to conventional titration using silver nitrate solution. This new CE protocol will contribute to applied research and help plants to better understand and eventually control the behaviour of cyanidation circuits."

Jan 1, 2011

By C. M. Davidson, D. J. Drexler

"Sulphuric acid treated with hydrogen peroxide to destroy organic contaminants could conceivably show increased corrosivity toward carbon steel shipping and storage vessels, caused by the persistence of a peroxide residual. This paper describes work performed to determine the effect of 0-200ppm hydrogen peroxide on the corrosion of carbon steel by 93% and 98% sulphuric acid at room temperature (23ºC) and 50ºC.Steel electrodes were exposed to acid containing several peroxide levels (0. 45, iOO and 200 ppm) for up to two weeks. Specimens were removed at intervals and weight loss, open circuit potential, depth of metal loss and residual peroxide concentration recorded.Hydrogen peroxide decomposes considerably over two weeks in iron-contaminated sulphuric acid. initial peroxide concentrations > l00 ppm suppress corrosion, but the effect is lost when concentration decays below about 60 ppm. Sustained peroxide levels in the range below 60 ppm may increase corrosion rates. These phenomena are interpreted by analogy with anodic passivation."

Jan 1, 1987

By H. Kolcz, G. S. Dobby, R. Stratton-Crawley, S. W. Wilson

"The Matte Separation plant at Inco's Copper Cliff Smelter Complex is described. The continuing implementation of flotation column technology in the flowsheet in various applications is reviewed. Comparative studies on 0.038, 0.10, 1.1 and 1.8 m diameter columns have been carried out. It was demonstrated that consistent metallurgical performance was obtained with both pilot- and plant-scale units. Grade-recovery relationships for plant columns can be predicted with confidence from data obtained from test equipment. The work indicates further areas of the flowsheet in which columns present an attractive alternative to conventional cells. INCO’s MATTE SEPARATION PROCESSNickel concentrate from Inco’s Sudbury area mills has been processed in the Copper Cliff smelter for sixty years. Prior to that, Sudbury ores had been smelted directly. Historically, copper-nickel separation from smelter converter matte was achieved by the classical Orford process. In the mid-1940s Inco developed an improved separation scheme based on mineral processing methods, the Matte Separation Process. A generalized Copper Cliff Smelter Complex flowsheet is shown in Figure 1.Iron sulfide and gangue contained in the nickel concentrate are rejected in the smelting-converting process. The molten product, typically containing 50% Ni, 25% CU and 22% s, is cast at about 1000 ºC, into floor moulds and allowed to slowly cool for four days. During this period nickel sulfide (heazlewoodite, Ni,S,), copper sulfide (chalcocite, cu,S) and a copper-nickel metallic alloy precipitate and form a coarse grain structure that is amenable to separation by physical means. The phase chemistry of this system has been described previously by Sproule et al (1). This matte then becomes the feed to the Matte Separation Process.A simplified block flowsheet of the Matte Separation Process is shown in Figure 2. Matte ingots, typically weighing 20 tonnes each, are broken and crushed in a three stage crushing plant to approximately minus 0.01 m and conveyed to the Matte Separation building. Grinding is carried out in two parallel circuits each consisting of a rod and ball mill in series producing a flotation feed which is 65% minus 44 microns. Typical throughput of each grinding circuit is 650 tonnes/day. The metallic fraction of the feed is recovered by magnetic separation. This product, containing about 66% Ni and 15% CU, is a major component of the feed to the Copper Cliff Nickel Refinery."

Jan 1, 1990

By Corby G. Anderson

"Laboratory testing, plant optimization, and the interpretation and application of metallurgical technologies can be tedious, time consuming and costly. This paper outlines the use of proven statistical design of experimentation software for rapid laboratory testing and optimization of operating plants with limited representative sample utilization. This results in less costly required testing, a more thorough understanding of results and the ability to simultaneously optimize several variables and outcomes at once. At the Center for Advanced Mineral and Metallurgical Processing (CAMP), this testing methodology has been used successfully in many metallurgical development and plant optimization projects thereby confirming its real world utility and application. Accordingly, several applied examples in flotation and hydrometallurgy will be outlined in this paper. This will include flotation testing of a copper gold ore, flotation testing of a copper, cobalt and gold ore, optimization of an industrial hydrometallurgical jarosite circuit and optimization of industrial nitrogen species catalyzed pressure leaching of a copper enargite concentrate.INTRODUCTIONWhile flotation technology is now 100 years old, the testing, interpretation and application of lab results can be tedious, costly and time consuming requiring extensive sample collection and preparation. In addition, recent applications like hydrometallurgical pressure leaching and associated unit operations, such as precipitation, still remain more of an art than a quantifiable science. This paper will elucidate the application of STAT-EASE Design-Expert software to minimize required laboratory testing while rapidly optimizing multiple results and outcomes in a statistically valid manner. The STAT-EASE program is based on proven design of experiment fundamentals. In this paper, the real world application of this methodology for lab testing, plant optimization and process development will be elucidated."

Jan 1, 2006

By J. Dong

"Xanthate is a sulfide collector that has been widely used in flotation for almost a century. It is inexpensive, easy to synthesize and apply, and produces good metallurgy in the right applications. However, a major drawback of xanthate is that it decomposes easily and generates CS2 gas in transportation, storage and operation, which can be harmful to human health. Also, excessive xanthate in tailings pond leads to toxicity of the process water and potential damages to aqua-life systems. New regulations in Ontario require that the TWA (time-weighted-average) value of CS2 in the work place is below 1 ppm, which is 1/10 of the previous limit. The stringent regulation may eventually sweep other regions of Canada with the increased awareness of healthy working conditions and environment protection. Therefore, it becomes very important to find xanthate replacements which will be “green”, i.e., environmentally friendly.In this research work, a systematic procedure is used for collector evaluation using the Sudbury nickel sulfide ores from Vale’s Ontario operations, starting with the collector properties (MSDS) evaluation, followed by batch flotation tests, miniplant tests, plant trials and economic evaluation. It is found that the most promising xanthate replacement is dithiocarbamate.INTRODUCTIONSulfide mineral flotation has been practiced since the early 20th century. Its industrial importance is well recognized as mineral concentrates from flotation can be economically smelted and refined to provide primary metals. Collectors play a vital role in froth flotation. There are reagents possessing both a polar group that binds them to the mineral surface and a nonpolar group that is oriented away from the surface to attach air bubbles. The introduction of xanthate as a sulfide collector in 1925 was a remarkable development in froth flotation (Keller, 1925). It is low cost, easy to synthesize, water soluble, simple to control in application. Most importantly, it has strong capability and usually good selectivity for sulfide mineral flotation, which have been keeping its application prominent for almost a century."

Jan 1, 2011

By Tim Hughes, A. H. (Sandy) Gray, Jennifer Abols

"The selective recovery of gold and silver from solutions containing other metals such as copper is possible using AuRIX®100 resin in conjunction with the Gekko Resin Column. Selectivity is driven by controlling the solution pH, which enables activities such as loading copper, gold and silver and then selectively stripping copper before gold and silver. Alternatively gold and silver can be loaded and the copper left in solution. The selective loading of gold while reducing the silver loading has also been demonstrated opening the possibility of producing high grade gold doré from high grade silver pregnant leach solutions. This paper reviews the AuRIX®100 resin and Gekko Resin Column Technologies, discusses the uses of AuRIX®100 in the recovery of gold and silver and the chemistry relating to several projects for which AuRIX®100 is being tested.INTRODUCTIONGekko SystemsGekko Systems specializes in the design, development and distribution of innovative mineral processing equipment and systems with a particular focus on gravity separation for the gold and diamond industries. The company, which has been around since 1996, has five main products: the InLine Pressure Jig, the InLine Spinner, the InLine Leach Reactor (ILR), Gekko Resin Column and Modular Systems.The InLine Leach Reactor is an intensive cyanidation reactor that uses high cyanide (0.5 – 2 % NaCN) and high oxidant (20 ppm dissolved oxygen as O2 or hydrogen peroxide) to dissolve gold from medium and high-grade gravity or flotation concentrates. The ILR, which typically replaces a shaking table in the gold room, is available in both batch and continuous models. There are 42 installations worldwide. Further details on this technology can be found in papers written by Gray et al (2003) and Longley, McCallum and Katsikaros (2003). By replacing a shaking table with an ILR, the overall gravity and plant recoveries can be increased significantly. Other advantages include reduced security risks, lower operating costs, reduced operator involvement due to the automatic process and increased safety for gold room operators."

Jan 1, 2006

By Pritii Tam Wai Yin, Tony Leong, Neetu Bansal, James Vaughan, Amiel Boullemant

Mercury is a toxic element that is associated with many industrial activities including the Bayer process. Mercury is known to enter the Bayer process with the bauxite feed material and has the potential to accumulate as the process solution is recycled. This paper explores the speciation of mercury in Bayer process streams. The process parameters considered are the oxidising-reducing potential, basicity and temperature. The results of a refinery circuit survey are presented and compared with the thermodynamic predictions. Electrochemical measurements on relevant synthetic systems are also included.

Jan 1, 2014

By P. L. Drake

This paper comprises a discussion of the role which mineral resources will play in Canada's future export trade and the growing demand for minerals in Canada.

Jan 1, 1979