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By C. Fortin

ABSTRACT The subject of gold flotation has been reviewed extensively. Most of these reviews focus on the theories of gold flotation and the physical and chemical effects that may impact the efficacy of the gold flotation process. The current status of gold flotation chemistry as it is being applied in industry has not been widely addressed. This paper reviews current gold flotation practice and research advancements and discusses how these applications tie in with the current understanding of gold flotation chemistry. Survey results from worldwide gold flotation operations are analyzed. Potential future areas of gold flotation research are highlighted.

Jan 1, 2013

By Wei Zhang, Jinhong Zhang

"The adsorption of ethyl xanthate on copper sulfides, i.e., chalcopyrite, chalcocite and bornite, has been studied in situ in aqueous solutions by applying an atomic force microscopy (AFM). AFM images show that xanthate, such as potassium ethyl xanthate (KEX), adsorbs strongly on chalcocite and bornite mainly in the form of insoluble metal xanthate, which binds strongly with the mineral surface without being removed by flushing with ethanol alcohol. This adsorption mechanism is totally different from the one obtained with chalcopyrite/xanthate system, during which oily dixanthogen is the main adsorption product on chalcopyrite surface. The findings obtained from the present AFM study suggest that an AFM image analysis is a powerful tool for the study of the collector’s adsorption on mineral surface and as well the development of novel collector for copper sulfide flotation.INTRODUCTIONIn mining industry, copper sulfide minerals, i.e., chalcopyrite, chalcocite and bornite, are usually separated selectively from non-valuable gangue by froth flotation, which treats the highest throughput and produces the maximum economic outcome of any surface chemistry process. In flotation, collectors are added into the pulp (mixture of water and fine-grained minerals) to selectively adsorb onto the target mineral and render its surface with high hydrophobicity, which is generally beneficial for a strong mineralbubble attachment and thus a high flotation recovery.The adsorption of collector on mineral surface, therefore, is vital for a successful flotation process and it has been studied by applying various surface analysis techniques, such as IR (Infrared Spectroscopy), CV (Cyclic Voltammetry) and XPS (X-ray Photoelectron Spectroscopy). (Poling, 1963; Allison et al., 1972; Mielczarski et al., 1984; Leppinen et al., 1989; Kartio et al., 1996) These studies have revealed a lot of information, such as the reaction, product and mechanism, of the adsorption of chemicals on mineral surface. It is also of great interest to directly get the image of adsorbed collectors on mineral surface changing with pulp chemistry, such as pH, redox potential, ionic strength and chemical’s dosage."

Jan 1, 2016

By Robert White

?Introduction of BMS?Paste fill generalities?Development through paste?Development through rock fill?Conclusion ?Brunswick mine is operated by Xstrata. The mine has been in operation since 1964 and produces around 10 000 tons per day of ore containing (in order) zinc, lead and silver? The ore body consists of close to ten sub-parallel massive sulfide lenses. The length of the ore body is 1200 m with a width of up to 200 m. From the surface, the ore body extends to a depth to 1200m ?There is 100 km of active drifts for a total 400 km ?The mine is divided by 7 levels and 23 actives sub levels

Feb 1, 2008

By M. Fan, H. E. Wyslouzil, J. Kohmeunch

Eriez HydroFloat(TM) separators and Canadian Process Technologies (CPT) flotation columns have been developed to overcome the limitations of traditional flotation cells in recovering coarse and fine particles, respectively. The flotation column can effectively separate 30-5 µm phosphate. Several industrial-scale HydroFloat separators have been installed in phosphate and potash beneficiation plants. Industrial-scale ultra-coarse (+850 µm) phosphate separation results suggest that a more-than 40% BonePhosphate- of-Lime (BPL) recovery increase and a 37% collector consumption reduction can be achieved. The paper describes the applications of Eriez HydroFloat separators to coarse particle separation and the CPT flotation column to fine/ultrafine particle flotation.

Jan 1, 2009

By R. D. Lindsay

Originally the focus of Deak Resources Corporation Business Plan was to establish a method for treating small gold and possibly base metal mineral deposits located in the Kirkland Lake - Noranda area of Northeastern Ontario, Northwestern Quebec at a central treatment facility. Since the establishment of this original business plan in 1988 other processing options have availed themselves for handling the base metal ores off site at a central facility which may preclude their processing at Deak.The site selected for the Deak processing plant was Kerr Addison's Virginiatown operation. At the time this property was acquired from the Receiver following Golden Shield Resources' Bankruptcy in 1989 the mill had been processing in the order of 1, 100 SDT per calendar day through one processing module; a module originally designed to process 1,500 SDT/day of a free milling gold ore. This tonnage level however had not been achieved since 1966 when an average throughput of 1481 SDT per calendar day was recorded.In order to realize Deak's overall Business Plan it would be necessary to expand the mills processing capabilities to provide:(1) A 2200 SOT per day circuit capable of processing a free milling, medium work index gold ore;(2) a 1 ,000 SDT per day flotation and/or cyanidation circuit capable of processing refractory gold bearing materials containing refractory minerals (i.e. copper) that should be removed prior to cyanidation; and possibly(3) a 1200 to 1500 SDT/day base metal circuit capable of processing the broad range of Deaks' Base Metal Property ores. If this circuit were introduced it would be completed in two tonnage phases.Further, it was recognized when operations resumed under Deak in 1990 that the existing tailings dam was suitable for, and had sufficient capacity for additional gold tailings with necessary physical modifications and changes in disposal techniques (including the construction of containment storage cells) that would allow storage for an additional 3.4 million tons of gold ore tailings approximately 1.0 million of which has been deposited since 1990. The focus of Deak's long term tailings disposal strategy is to acquire the Barber Lake Basin which is currently adjoined to our main tailings system which will provide an additional 10 million tons of storage capacity.

Jan 1, 1993

By Fernando Canales

In the last decade a great dealt of attention has been paid to the chemistry of polynuclear gold derivatives with a central heteroatom, not only from the experimental and structural but also from the theoretical standpoint (1). Interesting hypercoordinated species of the type [C(AuPR3)5]+, [C(AuPR3)6]2+, [N(AuPR3)5]2+, [P(AuPR3)5]2+ and [P(AuPR3)6]3+ have been described (2), apart from other complexes with more conventional stoichiometry, and all have in common the presence of gold-gold interactions of ca. 3 Å. Usually, the chemistry of the first row elements of the p-block is known to follow classical rules of bonding, and only in cases of extreme electron-deficiency has the traditional electron count to be reconsidered to account for special types of molecular or solid state structures. Many of these heteroatomcentered complexes are electron-deficient and the gold-gold interactions provide a significant contribution to their stability. The attraction between these closed-shell systems has recently captured the attention in inorganic and organometallic chemistry (1). P. Pyykkö has summarized the available theoretical and experimental evidence of intra- and inter-molecular interactions between heavy metal atoms, such as Au(I) (3). In general, when heavy metals are involved in such interaction, the closed-shell attractions are of metallophilic or van der Waals type, as has been found for d8, d10 coinage-metals, and d10s2 centers. Experimental evidence for the aurophilic Au(I)???Au(I) attraction is available from crystallography, NMR and Raman spectroscopies, and optical spectroscopic measurements of the interaction strength (4). It is manifested in molecular conformations with relatively close Au???Au interactions of ca. 3 Å, whose strength has been estimated at ca. 25-50 kJ/mol (5). These attractions are weaker than most covalent or ionic bonds, but stronger than other van der Waals bonds and comparable in strength to typical hydrogen bonds. The phenomenon cannot be satisfactorily explained by classical theories such as hybridization (3). From a theoretical point of view, the attractions close to equilibrium distances are caused by dispersive interactions together with relativistic effects (6). The attractive contributions are dominated by pair-excitations from the heavy metal, such as gold, strengthened by relativistic effects. In all the cases where there are inter- or intramolecular metal-metal attractions, the correlation effects are essential; if they are omitted, at the Hartree-Fock (HF) level, repulsive interactions are obtained (6). Hence, it is necessary to use at least second-order Møller-Plesset level (MP2) methods for the dispersive forces, which are included in the electronic correlation effects (7).

Oct 1, 2003

By K. Soldenhoff, M. Fainerman-Melnikova

The use of strong base resins for uranium recovery is severely affected by the presence of chloride ions in solution. In areas where high-quality process water is not readily available, the use of saline water would extend the potential application for ion exchange in uranium processing. This study presents measurements of uranium uptake, using a wide range of commercially available weak base anionic exchangers, from solutions with chloride concentrations ranging from 2.5 to 22 g/L Cl. Out of 14 weak base anionic resins tested, 3 were identified that were not severely impacted by the presence of chloride and significantly outperformed a gel strong base resin typically used for uranium recovery in high-chloride environments. The uranium loading was sufficiently high for the consideration of development of the application of uranium recovery from uranium ores leached with seawater.

Jan 1, 2012

By Maurice Séguin

The primary aim of all ground geophysical work has been, of course, to locate orebodies. As with any geo-physical method, its success depends on a proper mastering of the types of surveys and equipment used and their application to the physical properties associated with the orebodies. The Schefferville deposits are iron ores subjected to enrichment by the process of leaching. Although some ore types are porous and low in demiity, most of the ore zones have had a net increase in density brought about by enrichment. In the course of their formation, the magnetic characteristics of the rocks have usually changed, as much of the magnetite was altered to relatively non-magnetic iron oxides and hydrous iron oxides. Ali drift-covered areas underlain with iron-formation are potential ore-producing areas. From these first two physical proper-ties and a determination of the thickness of the over-burden, a combined gravity-magnetic-seismic and/or resistivity survey allows for the detection and sorting out of iron-formation and potential ore zones from the country rocks. If the iron-formation possessed relatively uniform physical and chemical properties, the problem of locating areas underlain with ore, using geophysical methods, would be greatly simplified. Unfortunately, the iron-formation is a complex assemblage of rock types, each having different physical and chemical characteristics. In spite of this, qualitative and semi-quantitative correlation between the results of the surveys and the geology and structure of the area could be established. In addition, a semi-quantitative to quantitative correlation of the values of the residual gravity anomalies with the specific gravity, the iron content, the porosity factor, the dimensions of the under-lying orebodies and the values of the ground magnetic intensity above a reference lithologie unit, with the per cent weight Fe304 recovery and the susceptibility, led to the discovery of a direct-shipping iron ore deposit in the Schefferville mining district of Canada.

Jan 1, 1968

By Zainelabdin Khalid Zainelabdin Elfaki

The influence of partially replacing cement with marble waste on the workability and compressive strength of concrete bricks was investigated. Three replacement percentages, 10%, 20% and 30% weight marble waste, were used with different curing times of 7, 14 and 28 days. Two specimens were prepared for each percentage and curing time. For this study, marble powder from the Mining House Company in Saudi Arabia was used. It was observed that the replacement of cement in Concrete brick with marble waste enhanced the loading strength and the workability of the prepared concrete bricks. It was also observed that 20% replacement of cement with marble waste was the best replacement percentage compared to the other replacement percentages tested. Marble waste from manufacturing companies, either in powder, sludge or slab form, has negative impacts on the environment. In contrast, reusing marble waste has both economic benefits (i.e., selling the marble waste) and lessening the need for raw resources.

Jan 1, 2014

By Ron Tessier, Claude Bazin, Robert Grant, Mike Cooper

"Grinding simulators are now widely available to assist in the optimization of industrial circuits. They provide circuit operating conditions or flowsheet designs that yield a given product size distribution. However, they do not provide information of the impact of a change of product size distribution on the subsequent flotation or leaching stages. This paper presents a method to predict grade and recovery indices for a flotation plant as a function of the flotation feed size distribution. The application of the method to various size distributions allows the determination of the optimal fineness of grind. A case study for a CuPb rougher circuit of a New Brunswick complex sulphide processing plant is presented to illustrate the method.IntroductionIs the grinding circuit product fineness optimum for the subsequent separation steps? This is a question that is certainly very difficult, but critical, to answer. Laboratory and pilot plant testworks can provide clues as to whether grind should be finer or coarser. For a full scale operation there is no other way than trying to change the setup of the grinding circuit and verify the effect on flotation. True effects can, however, be masked by the numerous and unexpected disturbances inherent to grinding and flotation circuit operations. A good preliminary investigation requires a noise free environment to elaborate possible solutions for the question.Plant simulators provide this noise free environment. However, despite grinding and flotation simulators having evolved significantly for the last 20 years, very little is available on the integration of both simulators to analyze the effect of fineness of grind on metallurgical performances. For instance, a grinding circuit simulator may help to find the tuning of a grinding circuit that will yield the desired fineness of grind, but does not inform on the effect the new product size distribution will have on the separation stages. Linking grinding and flotation would require a flotation plant simulator with the rate and infinite recovery parameters for each mineral in each size interval considered. This approach is seldom used because of the tedious work required to estimate the model parameters. Recently Leroux(1992) proposed a method to predict mineral liberation from grinding ore of known mineralogical texture. Although the method is still at its infancy it may provide, when combined with a reagent conditioning model (e.g Niemi et al., 1982; Bazin et al., 1988), a way to simulate flotation without the need of entering the numerous parameters of a flotation model."

Jan 1, 1994

By L. Tong

"The oxidation of Quebracho was evaluated by acid-butanol assay, which indicates depolymerization of Quebracho. Anthocyanidin, an oxidation product of Quebracho, is stable at 95?C for up to 2 h. The ionization, complexation, and oxidation properties of Quebracho were discussed. Complexation of metal-Quebracho occurs at ambient temperature. The formation of complex precipitates is influenced by the acidity of the solution. Temperature is another important parameter that influences the oxidation and the complexation of Quebracho. Quebracho-ferric complex precipitate forms at 90?C, 0.1 mol/L H2SO4. The formation of Quebracho-metal complex in the leach solution is a possible reason for the consumption of Quebracho. Quebracho molecules adsorption on the mineral surface is reduced by consumption of Quebracho, resulting in poor sulfur dispersing effect in the leaching process. INTRODUCTIONQuebracho is used as a sulfur dispersing agent (SDA) in the pressure leaching of zinc concentrate as stated in U.S. Patent No. 3,867,268 (1975). It prevents the zinc sulfide particles from being coated with molten sulfur, thus preventing the inhibition of the zinc leaching reaction. Recently, the sulfur dispersing effect of Quebracho was investigated in the oxygen pressure leaching of nickel concentrate. The oxygen pressure leaching of pentlandite can be represented by reactions 1-3."

Jan 1, 2012

By Jean-Jacques Bouillon, Michel Jébrak, Stephane Faure

"Le gisement polymétallique (Cu-Zn-Au-Ag) des Mines Selbaie est forme par un réseau de filons encaisses dans une séquence de pyroclastites felsiques du sill on Harricana-Turgeon. Les minéralisations sont encaissées dans le tuf de Selbaie, situe sous une épaisse séquence d'ignimbrites Iitées. Ce gisement se distingue des autres gites archéens par une chronologie atypique des minéralisations: les veines de chalcopyrite, de sphalérite et de galène recoupent un amas exhalatifpyriteux stérile. Un vaste halo d'altération hydrothermale a chlorite et mica blanc est associe à cette minéralisation.La mise en place des veines minéralisées est associée à une phase d'extension NNW-SSE. Le complexe volcanique subit, par la suite, trois phases de déformation. Une compression, orienté N-S, développe une schistosité à peine pénétrative et un réseau de fentes de tension. Une réorientation des contraintes locales selon une direction WNW-ESE conduit au chevauchement de I' écaille d'andésite et de tonalite de Brouillan. Un réseau conjugue de failles normales cassantes est associe au relâchement des contraintes."

Jan 1, 1990

By Lawrence Devon Smith

"The Management and Economics Society has undertaken a survey of industry practice in the evaluation of mineral projects. The survey addresses a number of issues relating to evaluation techniques, discounted cash flow methodology, and risk. Completed during the spring and summer of2005, the results provide a record of opinion at an active and vital time in our industry.The 2005 survey questionnaire was distributed by e-mail to groups and organizations around the world. There were 22 respondents out of several hundred questionnaires distributed (we gather this small proportion of respondents is typical for such surveys). The responses, although a small number, show a consistency that suggests that the survey has captured the views of the industry. The results of the survey are summarized below in series of tables and graphs.The reader is cautioned that the results are a snapshot of industry practice at a point in time as represented by a small sampling of the industry's practitioners. These results should be viewed as indicative values."

Jan 1, 2003

By Nichols. R. S.

"Surface coal mining production from Elk Valley and area in southeastern British Columbia began in 1913. Since 1970, five open-pit mines have been put into production: Westar Mining&apos;s Hanner and Greenhills Operations; Fording Coal&apos;s Fording River Operation; Byron Creek Collieries&apos; Coal Mountain Mine and Crows Nest Resources&apos; Line Creek Operation.ln 1983 these mines produced 14.9 million tonnes of raw coal at an average strip ratio of 4.9 bank cubic metres of waste to 1.0 tonne of raw coal. This is 70% of the estimated 21.1 M tonnes annual capacity .Multiple seams are recovered with truck/shovel and dragline equipment. There is a wide range of equipment types in use with a recent trend toward larger and more mobile equipment.Coal mining in Elk Valley involves advancing along strike in four steps: hangingwall waste removal; seam cleaning; coal recovery; and foot wall waste removal. Each mine is unique in its approach to these four steps but the truck/shovel methods can be categorized into three main groups: seam dips < 35 degrees as at Harmer, Fording and Greenhills; seam dips 35 to 50 degrees as at Line Creek; and seam dips >50 degrees as at Byron Creek. Dragline mining at Fording involves bath waste and coal removal by draglines."

Jan 1, 1984

By Richard D. Moffett

The MineSight® Implicit Modeler arms geologists, engineers and surveyors with a better approach to 3D modeling. Use the tool to quickly retrieve a 3D wireframe from drillhole data and onscreen interpretation. Generate faster and more informed decisions to guide future work and improve reproducibility of results. Implicit Modeling is a mathematical surface fitting method that interpolates points to give a smooth and realistic fit. Control results by mixing planar, sectional and non-orthogonal polygons or polylines, as well as drillhole information to create solids or surfaces. The outcomes are particularly valuable to identify ore body trends, generate 3D contours of drillhole intercepts, or produce cut-off 3D maps. MineSight Implicit Modeler (MSIM) is fully integrated in MineSight?s robust and versatile suite of products, allowing you to interpret, interpolate and calculate while moving between applications. It connects seamlessly with the MineSight Torque SQL database, offering access to extensive filtering options. MSIM makes modeling much faster, allowing geologists more time to analyze data and test theories. The presentation will reveal how MSIM complements MineSight?s geomodeling workflow.

May 1, 2013

By G. P. Gormley

"Future open pit metallurgical coal mines in western Canada will be developed in complex geological environments. The success of these operations will be influenced by the mine operators&apos; ability to prepare accurate mine plans and to predict and, subsequently, 10 control both out-of-seam dilution and coal recovery. Quintette Coal Limited has been mining its tightly folded and severely faulted Mesa depo sit at annual rates of up to 9 Mt of raw coal, since October 1982. Ongoing development drilling combined with continuous utilization of blast hole information, has been required to achieve an acceptable geological data base for short range mine planning. Thrust faulting has been a primary geological cause of difficulty in selectively mining waste and coal, which has resulted in higher than expected dilution in plant feed. The same geological phenomenon has also increased reserves by 6.3% and allowed for expanded mine plans to include a lower thrust plate, ultimately doubling the mines original reserve base. This paper illustrates the geology of the Mesa deposit and the type of work involved in its interpretation. Regional GeologyThe Quintette Coal Limited (QCL) property is located in the Peace River Coal Field of northeastern British Columbia. In this area, northwesterly-trending folds of the Rocky Mountain foothills are commonly cut by multiple, low-angle thrust faults, which dip to the southwest. The Lower Cretaceous Gates Formation, of near shore continental origin, contains 5 to 7 mineable seams of medium volatile bituminous metallurgical coal (Figs. I and 2). These seams normally range in thickness between 0.75 m and 9.5 m and have an aggregate thickness of between 15 m and 22 m."

Jan 1, 1988

By R. Sharma, I. Miskovic, S. Miskovic

Solvent extraction (SX) is a widely used method for the extraction of copper from pregnant leach solutions or other ionic solutions in hydrometallurgical applications. About 17% of total refined copper production worldwide is produced using SX followed by electrowinning (EW). Conventional SX units, such as mixer-settlers, consume a large amount of extractant, offer poor process control and yield low extraction efficiency. Extraction efficiency is poor due to low specific interface area, crud formation, emulsification, and slow phase separation stage. Micro solvent extraction (micro-SX) is a rapidly developing technology that provides an opportunity for improved process control, higher extraction efficiency, lower residence time and, as such, has a potential to reduce the environmental footprint of SX operation. In this research, extraction of copper ions in an acetate buffer media is investigated using D2EHPA with kerosene as a diluent. Chemical factors such as extractant concentration and ionic concentration of aqueous phase are varied to determine the optimum conditions. Subsequently, the extraction efficiency and reaction time of new micro-SX reactors are compared against previous bulk SX studies. Extraction in the microfluidic reactor was observed to be faster with a residence time more than an order of magnitude lesser than bulk SX. This study forms a prelude for developing new modular micro-SX units which will enable continuous, effective, and safe operation on a large scale. In future studies, numerical and analytical models validated through this work will help eliminate rigorous experimentation and enable faster design and fabrication of micro-SX units. INTRODUCTION Conventional industrial solvent extraction (SX) units such as mixer-settlers, extraction columns present various disadvantages. Low specific interfacial area, crud formation, and emulsification in industrial reactors lead to long extraction times and severely hamper extraction efficiency (Priest et al., 2011; Chen et al., 2017). Microfluidic extraction considerably improves upon the current extraction practices by (1) creating a large surface to volume ratio that enables rapid mass transfer across the interface, (2) better process control, and (3) easier separation of phases (Kashid, Renken, & Kiwi-Minsker, 2011; Ciceri, Perera, & Stevens, 2014). These factors establish micro-SX as a crucial mode for process intensification. Although, a micro SX unit has significantly low processing volume than conventional extraction methods, their throughput can be increased via massive parallelisation (‘numbering up’), which is an area of active research (Darekar, Singh, Mukhopadhyay, & Shenoy, 2016a; Kriel, Woollam, Gordon, Grant, & Priest, 2016).

Jan 1, 2019

By F. P. Hassani, Jacque Ouellet, M. Hossein

A laboratory investigation was undertaken to evaluate the effectiveness of different binding agents in a paste backfilling operation suitable to be used in a sulphide-rich environment. Different combinations of Portland cement and fly ash type C as well as ferrous slag were used as the binding agents. The unconfined compressive strength of the samples was measured for extended curing periods. The results indicate that the addition of 3% slag in the binding agent mix could produce strengths up to 0.5 MPa in the samples under investigation. For higher binding contents, the addition of Portland cement will lead to higher availability of calcium hydroxide and calcium aluminate, which are susceptible to deterioration from the phenomenon known as sulphate attack. Using slag, on the other hand, will reduce the permeability, availability of calcium hydroxide, and dilute the calcium aluminate ions reducing the susceptibility of the samples to sulphate attack. However, gypsum will form which could have the same detrimental effect on the strength of the treated matrix. Therefore, special attention must be given to the content and properties of agents used to activate the pozzolanic properties of the slag.

Jan 1, 2001

By G. C. Hambleton

"The author has had wide experience in the reclamation of coal from coal mine waste dumps in the United Kingdom.The paper includes such topics as the processing decision and factors affecting processability; method of testing and appraisal; test data interpretation; historical influences in apppraisal; special contaminants and processing difficulties; methods of treatment; review of systems in use and their comparative economics; over-all system economics including excavation, handling methods, recovery system and shale disposal; effluent treatment; environmental considerations; alternatives to processing for coal recovery; light aggregate and cement usage; burned shale heaps; land reclamation; shale deposition for encouragement of vegetation by natural or artificial means; use of tailings fines; the environmental argument for action."

Jan 1, 1972

By J B. Maughan

Gas and oil seeps have been known in Quebec for more than one hundred years. These occur in three main areas which contain sedimentary rocks with a total thickness estimated to vary from 6,000 to 20,000 feet. The strata in these areas are similar in many respects to those in producing areas of southwestern Ontario and the Appalachian basin, and the prospects for finding and developing commercial reserves of oil and gas in Quebec would therefore also appear to be favourable. Little of the exploratory drilling to date has been con-ducted in a systematic manner, and most of the drilling has utilized improper or inadequate equipment. Many wells have also failed to adequately test and fully evaluate the principal zones of interest. Relatively high drilling costs have hindered systematic exploration; however, with improved portable equipment, it is expected that future wells can be drilled with greater efficiency and at less cost. Most of the mineral rights in Quebec are held by the Provincial Government, and acreage can still be leased in large blocks on favourable terms.

Jan 1, 1964