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By A. Mazhary

"Although ore sorting in mining is not a new concept, sensor-based sorting has failed to gain broad acceptance due to perceived challenges with the technology. In order to gain wider applications, this research focuses on treating waste rock and low-grade ore to identify and test appropriate sensors and to evaluate the response. Results showed that amenability of rocks to sensor-based ore sorting is both sensor and ore specific. It was also observed that the efficiency (recovery) of sorting is directly influenced by the degree of heterogeneity of the rocks. The overall outcome showed that with the right sensor, several of the materials tested are amenable to sensor-based ore sorting. Mining companies could benefit from multiple economic and design impacts, such as lower energy cost, lower transportation costs, higher metal recoveries and smaller footprints that lead to more sustainable mining. This paper will focus on the effects of heterogeneity of rocks on sorting potential and efficiency.IntroductionSensor-based ore sorting has been attracting more attention since the pressure for effective resource extraction and management has increased. An urge to make most of the current deposits, and to make the low-grade deposits economic to mine has ushered the technology to find new ways to overcome the new challenges. No matter the terminology used, such as coarse beneificiation, waste rejection, particle or bulk sorting, the purpose of sensor-based ore sorting is to remove low-grade rocks before the comminution circuit, increasing the feed head grade and quality while reducing the energy costs related to comminution.Despite nominal advantages, there have always been some concerns that have impeded the intorduction and acceptance of the technology. One of the most important shortcomings of ore sorting is their capability, or capacity, to keep up with the high-tonnage mining. Some other issues that have been mentioned as drawbacks to sorting include installation cost of such devices, feed preparation for effiecient sorting along with accuracy of sorting and probability of false negatives (Manouchehri, 2003)."

Jan 1, 2015

By E. V. Manlapig, K. R. Rahal, J-P Franzidis

"The Floatability Characterisation Test Rig or FCTR is a highly instrumented, mobile flotation pilot plant built by Baker Process (now EIMCO) for the AMIRA P9 Project for use in flotation plant modelling and simulation studies. With the Mintek Floatstar system controlling the level in every cell, and the facility for full stream sampling on all streams, the FCTR is a unique tool for producing data of sufficient quality for flotation plant modelling. The plant was commissioned at Lonmin's Karee and Eastern Platinum concentrators in 1999/2000, and completed a number of test work programs to investigate the effect of power input and regrinding on metallurgical performance. Lonmin's experience with the FCTR has caused it to build two of its own to undertake further projects on its various mines. This paper describes the design of the FCTR and the features that make it a unique research tool, and the benefits derived by Lonmin through their experience with the unit.INTRODUCTIONAs part of the Australian Mineral Industries Research Association (AMIRA) P9 project, a new model for flotation has been developed, in which the overall recovery, R, of the jth floatability class of the ith size class of a particular mineral, is given as (Savassi, 1998):"

Jan 1, 2002

By C. V. Umipig, G. G. Hutalle, E. E. Israel

TVI Resource Development (Phils) Inc. Canatuan mine is a polymetallic ore deposit located in the Province of Zamboanga del Norte on the island of Mindanao in the Philippines. The deposit consisted of an oxidized capping of gossan overlying a Besshi type volcanogenic massive sulphide lens which is near surface and flat lying. Construction and development of a sulphide processing plant began in early 2007 and commissioned in November 2008. During the initial stages of sulphide operation, high copper (Cu)-low zinc (Zn) ore was fed to the plant. Marketable copper concentrate at 91-95% recovery was produced utilizing a high-pH bulk sulphide rougher flotation and 2 cleaning stages. Because of increased levels of Zn of the ore body, a Cu/Zn separation circuit was initiated in early 2010 following an intensive laboratory test work program. This Cu/Zn separation circuit was necessitated because of the copper ion pre-activation of the sphalerite that lead to the zinc being readily recovered to the copper rougher concentrate. In-situ activation of zinc (in the pit and stockpiles) was caused by the leaching of secondary copper minerals in the ore (particularly from the dominant copper species, chalcocite and covellite). This problem required the development of metallurgically complex and intensive reagent regime to effectively depress the activated sphalerite. As well, the immediate reactivation of zinc after it has been depressed, at the onset of Cu/Zn separation flotation, added additional metallurgical complexity to the process. Subsequent to the Cu/Zn separation circuit, an unconventional, yet proven effective, simultaneous cyanide detoxification-zinc flotation circuit was set-up to recover the zinc. Laboratory test work results realized Cu-Zn recovery differential from a Cu/Zn separation circuit of over 40-45%. This performance has been achieved in the plant, at 72% Cu overall recovery. With the gradual improvements on-going with zinc circuit capacity and effective zinc separation being achieved, zinc recovery has currently reached 40%.

Jan 1, 2012

By Tom Gabardi, Peter Clarke

"MillMapperTM is a new 3D laser scanning technology that has only recently been introduced into the North American mining industry. It enables mill operators to gain a much more complete understanding of the condition of their mill internals and to more accurately predict how liners will perform in the future. This paper describes the technology and techniques used to obtain data on internal mill conditions, how this data is processed into meaningful information which enables better prediction of liner life and gives examples of the reports provided by the software. Examples are given, using client sites data, on how this information is being used to reduce the costs and improve the revenue from SAG and ball mills.INTRODUCTION Scanalyse Pty Ltd developed the MillMapperTM technology in Australia over a number of years and has recently introduced it into North America with a significant take-up in Canada. The technology was commercially released in Australia in late 2006 and there has been significant technical development in the features provided since that time. MillMapperTM has been accepted as a useful technology in the Australasian region and more recently has been introduced to sites in Chile, Peru, Brazil, USA, Canada, Laos and South Africa. Over 100 different mills have been scanned and the technology has been thoroughly tested and validated. It has become an integral tool in condition monitoring and improvement programs for SAG and Ball mills across many sites and is now providing significant and measurable benefits to the mining industry. Some of these benefits will be described in this paper using actual examples."

Jan 1, 2012

By G. K. Mann

Fragmentation analysis of blast or crushed rock material is a time-consuming and costly process. During the last two decades, the mining industry has been investigating image-based analysis systems as an alternative to generate fragmentation results. Many image-based techniques and commercial products have emerged during the last few years, and the mining industry has recently begun using these tools for real-time estimation of size distributions. Some existing systems require manual image editing to add or delete edges (or net) before executing the fragmentation analysis routine. This manual procedure may take hours of time for each image analyzed. Reliable and robust image segmentation should be able to handle a wide range of rock textures and sizes under a variety of lighting conditions. This paper describes a novel software application, which has the capability to autonomously capture images and analyze them to generate the particle size distribution. The system can also process a batch of images captured during a fixed duration of time and produce the overall particle size distribution. The new method has different layers of segmentation modules, which allows the system to operate under a wide range of rock textures and lighting conditions. A new grey-level slicing technique is developed which can perform under a range of illuminating conditions. The Canny-based edge detection technique is used to segment rocks appearing in dark regions.

Jan 1, 2006

By Tano Balbin, Valery Astakhov, Juha Timperi, Lauri Koresaar

"Online elemental analysis is the basis of optimal flotation control in mineral concentrator plants. Traditionally XRF analyzers have been used as the online analysis method. However, online XRF analyzers struggle to measure elements below calcium in atomic number (Z=20). For many processes lighter element assays would be beneficial to improve control of grade and recovery. Processes where elements below Ca are required include P, Mg and Si in phosphate concentrators, Si, Mg and Al in iron concentrators, and S and C in gold concentrators. Laser-Induced Breakdown Spectroscopy (LIBS) based elemental analysis can readily be applied to these processes. LIBS is based on generating plasma in the slurry sample by a high energy laser and analysis of the plasma by optical emission spectroscopy. Capabilities of a new Courier® 8 analyzer based in LIBS technology are demonstrated for elemental analysis starting from lithium (Z=3). Results of a plant installation in a sulfide gold concentrator provide a good agreement with the analyzer and laboratory assays.IntroductionEffective process control can be regarded as one of the fastest paying investments for a mineral processing plant. Process optimization in flotation circuits requires constant feedback of the process state. If only manual laboratory samples are available, this optimization becomes difficult due to the long delay between taking the sample and acquiring the laboratory result. If the element grades are available in online basis, the operator or automatic process control system can make corrective actions in real time.Online X-Ray Fluorescence (XRF) analyzers have been in use at concentrators for decades. The XRF analyzers can provide a fast, accurate and precise analysis from slurry streams. However, the drawback of XRF analyzers is their lack of capability to measure elements below Ca (Z=20) in atomic number. The low energy X-rays of the low atomic number elements get absorbed by water in the sample, protective window of the analyzer, or air between the sample and spectrometer."

Jan 1, 2017

By Joe Pease

"The demand for minerals and metals is increasing. Head grades of ore bodies are dropping. Remaining ores are becoming finer grained, more complex, and more logistically challenging. Mineral processing – in particular comminution – already consumes a huge amount of energy. But in 20 years’ time, it will require about six times as much energy as today to meet the world’s mineral demand.Unless we do something different.As minerals professionals, it is our job to find that “something different”. The world is relying on us. Of course, we must look for new breakthrough technologies and techniques. We must find them, and we will find them – most likely in surprising areas.But what if we also already know how to make 30-50% improvements to efficiency? Just by using existing technologies, by applying modern analytical techniques, by custom designing our plants, by applying manufacturing principles, by breaking down our management silos between disciplines.The thing is, industry professionals already know this. Yet – in spite of a lot of intelligent people trying very hard – we just can’t seem to make it happen.This discussion considers why, despite our best efforts, we don’t get the best out of what we already have. Why we are wasting energy and money. Once we understand why, we can set about unlocking that value and improving industry productivity and energy efficiency. We will discuss the role that professionals and volunteer professional organisations like CMP and CEEC can play in catalysing the changes."

Jan 1, 2015

By Mike Robotham

When RFQ?s are received they often contain detailed technical specifications which suggest a departure from the suppliers own customary approach to the design. Both client and end user are quite rightly influenced by their own experiences. The question is who is right, the client and his consultant, the supplier or perhaps a combination of these. This paper looks at some of the fundamental variances that often occur in the approach to the mechanical design of drum hoists, based on our experiences of recent years. Director of Engineering, Mike Robotham is a chartered engineer and has been with DavyMarkham for over 30 years. Having completed a craft apprenticeship he later joined the engineering department as a junior engineer. He has a wealth of experience of working on medium to large engineering projects in the field of mechanical, electrical and hydraulic equipment

May 1, 2011

By Thomas. L. O.

Apart from a few sketches and incomplete maps, mainly topographical, and one or two detailed maps of placer-creeks, there is little information on the topography and geology of most of the country adjacent to the sections of the Alaska Highway in the Liard River area, particularly that part east of Kechika river. In 1943, the Geological Survey of Canada made a recon-naissance from Fort Nelson clown the river of that name to the Liard, thence up the latter to Hell Gate, and also up Beaver river for a distance of fifty miles. The whole of the area covered was found to be underlain by sedimentary rocks, not a single igneous dyke being seen. The British Columbia Department of Mines began reconnaissances near the highway both in and north of the drainage basin of Prophet and Muskwa rivers with a view to finding structures favourable for the accumulation of oil. In Liard River valley near the mouth of Smith river and at intervals from there clown to Devil' s Portage occur warm springs whose character and origin are not definitely' known, since they have not been investigated (21, p. 38A). Similar springs are said to occur at several localities over a broad belt extending from Muskwa river across the Liard to the Nahanni River country (26, p. 11). On Liard river below the mouth of Dease river, stratified sands, gravels, and clays of Pleistocene (?) age are constantly met with and in one or two places are underlain by sandy clays. The distribution of the latter, however, is very limited in the section cut by the river west of the Rocky mountains. The only range of these mountains that reaches the Liard is the high limestone ridge which approaches the mouth of Vents river from the southeast and then almost vanishes a few miles to the northwest of it (27, pp. 43-45). In general, the ranges of the Rockies in the area under consideration have been but little explored, but they are undoubtedly very largely sedimentary and, with the exception of some volcanics and intrusives on their western flanks, are probably almost entirely so. Unlike the high, deeply incised ranges in southern British Columbia, they dwindle in elevation north of Terminus mountain to low-wooded ridges separated by wide swampy valleys, and practically lose their identity between it and the Liard. The foothills, which, along the Liard, have a width of 38 miles (from near the mouth of Trout river to Hell Gate) are composed of a great series of alternating shales and sandstones, with some limestones, all folded closely together, which resemble those found in the foothills farther south (27, pp. 50, 19-20).

Jan 1, 1944

By John Frostiak

"Kahama Mining Corporation Limited, a wholly owned subsidiary of Barrick Gold Corporation, poured the first dore bar and filtered the first concentrate produced at the Bulyanhulu mine on February 28, 2001. This event marked the completion of the initial development of the Bulyanhulu Mine – Barrick’s first mine located outside of the Americas.Bulyanhulu is a 2,500 tpd underground mine located in the Lake Victoria gold belt of northern Tanzania. Gold is recovered as a gravity concentrate and smelted on site to produce dore bars or collected in copper concentrate that is shipped to offshore smelters. The facilities were constructed to meet Canadian standards. Unit operations include single stage crushing, SAG milling, gravity recovery, flotation, thickening and dewatering. Tailings are converted to paste and returned underground as paste backfill or pumped to the surface tailing site. The surface paste tailing disposal system is believed to be first of its kind in the gold industry. Paste disposal has several advantages over slurry, including lower dam construction costs, reduced water losses, and lower reclamation costs. This paper describes the facilities and discusses the challenges faced during development and construction including logistics, lack of infrastructure, recruiting and training, security, and social issues as well as initial operating results.INTRODUCTIONBarrick Gold Corporation completed the Bulyanhulu mine development in 2001. Capital cost of the project was US$280 million. The mine produced 241,575 ounces from start of milling to year end at a total cash cost of $197 per ounce. Numerous challenges were overcome in the mine’s development due to the general lack of infrastructure in Tanzania and the mine’s location some 1200 km inland by road from the port of Dar es Salaam."

Jan 1, 2003

By Anna M. Ferrero

Stability condition of underground excavations have to be assessed to guarantee safe operations within the quarrying working areas. This objective requires a reliable assessment of the rock mass natural state of stress and of the stress redistribution induced by the excavations. This goal is often complicated by difficult geological conditions induced by tectonic stresses, complex topographies and large and irregular excavation geometries. Consequently, the acting state of stress needs to be measured by specific in situ measurement devices. This work refers on an in situ measurements campaign carried out by CSIRO tests in an underground quarry located in the Carrara marble basin. The difficult path carried out for interpretation of the measurements is described in this paper. In particular, the numerical modeling performed using the Boundary Element Method (BEM) first, to study the influence of both surface topography and excavation geometry and then the Distinct Element Method (DEM) to evaluate the influence of rock discontinuities in the measurement zone are illustrated in this work. Parametrical analysis of the rock mass mechanical features is also described in order to calibrate the numerical models and analyze the experimental results. The work has been carried out trough several phases, which are: characterization of the rock mass through geostructural surveys: this allowed us to classify the rock mass and determine the mechanical and physical parameters necessary for modeling; on-site measurement of stress levels through the application of over coring techniques; numerical analyses for the simulation of excavation phases, using the Examine3D (BEM) engineering analysis code. comparison between the measured stress levels and those numerically calculated and subsequent calibration of the BEM model; Numerical model of the forecasted excavation based on the calibrated (BEM) model.

May 1, 2009

By Hasan Ozturk

Laboratory testing examined the effect of a variety of intrinsic rock properties and environment conditions that influence the adhesive bond between rock and thin spray-on liners. The liner materials used for these tests were Tekflex, provided by Fosroc, Castonite, provided by Rohms and Haas Co., Rockweb provided by Spray-on Plastics, and CS 1251 2K, provided by Master Builders. Some of the variables examined include: rock strength (tensile/compressive strength) rock mineralogy, rock surface roughness (grain size, fracture/joint roughness), and surface contamination (oil, water or dust). Under optimal conditions, adhesive strengths reaching at least 3 MPa can be achieved. Where the rock surface is contaminated with dust or the rock is weak in tension, it may be difficult to reach adhesion strengths of 1 to 1.5 MPa.

May 1, 2004

By William J. Purdy

Successful design, operation and completion of a surface waste management facility for a diamond mine located in Canada?s northern environment requires careful planning to minimize short and long term environmental impacts. As part of the mine development application process, best practice standards were applied using conventional engineering to reduce the environmental effects of the mine waste facility at the Snap Lake Diamond Project. This paper presents the design criteria, site conditions, material characteristics and engineering management objectives considered for optimization of the development plan. Insight into the engineering analyses, development alternatives, monitoring program and reclamation strategy plan to be undertaken during mine operations to provide opportunity for adaptive management and to minimize environmental impacts is provided.

May 1, 2004

By Turgut Yalcin

"Recent years have seen a resurgence of interest in flotation cell design, and one of the areas where attention is being focused is flotation in centrifugal fields which aims at increasing the flotation rates by forced bubble-particle contact.A new cycloflotation device was developed at Laurentian University and tested on the nickel ore of Falconbridge Limited in Sudbury. In comparison with conventional flotation, cycloflotation yielded at least seven times faster flotation rates in terms of the mass of solids floated per unit time per unit flotation volume, while producing concentrate grades similar to those of conventional flotation. These results, which were obtained with a bench-scale ""cyclofloat cell,"" suggest that cycloflotation has the potential of setting a new direction in flotation technology.IntroductionFroth flotation is no doubt the dominant separation technique in the mineral processing industry. Since its inception early in this century, much research effort has been and is still being expended on this process. Until recent years, emphasis seems to have been placed on the chemical aspects of flotation, but there is now an increased awareness for the need to improve flotation machine performance and more and more attention is being directed towards this area. In a 1982 article on ""Flotation Machines"" (Young 1982) it is stated that "" ... by now the design of the machines used would have reached a high level of perfection, ... In fact, this is not the case ... "".The process of flotation in a flotation device may be considered to take place in several distinct stages as follows:"

Jan 1, 1994

By W. J. Young, K. B. Macneill, C. N. Smith

"A BRIEF HISTORY OF THE MURRAY BROOK MINERAL DEPOSITDuring the mid-1950's intensive exploration activity in northern New Brunswick followed the discovery of the world class Brunswick base metal deposit. Using the prototypes of modern airborne geophysical and geochemical exploration techniques many mineralized areas in the Bathurst-Newcastle area were quickly identified. This base metal - silver camp is situated within the metavolcanic - metasidementary rocks of the Tetagouche Group which forms a roughly circular caldera-chaped voloanio complex of Ordivician age.One of the early results in the exploration history in the camp was the discovery of the Murray Brook Deposit by Kennco Explorations, (Canada) Limited. During routine ground checking of geophysical anomalies, most of which turned out to be graphitic schist, the discovery of some copper bearing float was made by the exploration team. This encouraged the company sufficiently to carry out a regional stream sampling program which lead to a large anomaly associated with a hematitic gossan. Diamond drilling of a weak Slingram anomaly over the gossan zone resulted in the discovery of massive sulphide lenses. This was followed in 1956-7 with an intensive drilling program. The result was the delineation of a potential ore body containing an estimated 23 million tons with an overall grade of 0.44% copper, 0.86% lead, 1.95% zinc, 25.73 g/tonne (0.91 oz/ton) silver, 0.28 g/tonne (0.01 oz/ton) gold. Within this package were higher grade zones of copper and lead-zinc mineralization approaching ore grades.A thick blanket of gossan was present and is reported to have caused the drillers considerable trouble as they attempted to penetrate it to get to the underlying sulphides. The gossan, consisting of iron oxides and silica fragments sits on top of the massive sulphides and attains a remarkable thickness of 45.5 meters (150'). Early work had suggested that the gossan was enriched in gold and silver. If this were the case and if the precious metal could be leached out with cyanide, then mining and recovering those values might be economic.With this in mind Northumberland Mines Limited optioned the property from Kennco in 1985. Preliminary leach tests indicated that indeed the gold in particular leached readily. Subsequent drilling of the gossan (using triple core barrel technology for better recovery of the easily ground core) indicated 1,536,363 tonnes (1,690,000 tons) with an average grade of 1.05 g/tonne (0.037 oz/ton) gold and 42.13 g/tonne"

Jan 1, 1993

By Ahmad Ghahreman, Lin Li

Silver and cupric ions have been proven to play the roles of catalysts to promote the oxidation kinetics of chalcopyrite in acid solution. In this study, the interaction between silver ions and cupric ions during ferric leaching of chalcopyrite in sulfuric acid solution has been investigated. The electrochemical study by Tafel analysis showed a significant boost of dissolution rate for chalcopyrite dissolution in Fe3+- Cu2+ containing sulfuric acid solution after Ag+ was added in the solution. For 10 ppm Ag addition, the dissolution rate of chalcopyrite increased to 7.94 ×10-6 A/cm2 from 3.2 ×10-7 A/cm2, when Ag+ was absent. On the other hand, the effect of Cu2+ on the dissolution of chalcopyrite in Fe3+-Ag+ containing sulfuric acid solution was not obvious from electrochemical measurements. The chalcopyrite leaching tests in different acid solutions showed that silver addition had an obvious catalytic effect on promoting chalcopyrite dissolution. Comparing the leaching rates of chalcopyrite leached in Fe3+ containing, Fe3+-Ag+ containing, Fe3+-Cu2+ containing and Fe3+-Cu2+-Ag+ containing sulfuric acid solutions, it was found in Ag+-Fe3+-Cu2+ containing sulfuric acid solution, the leaching rate was highest among all the aqueous acid systems. Further leaching tests suggested that with increase of the Ag+ concentration from 0 to 20 ppm, the leaching rate of chalcopyrite in Ag+-Fe3+-Cu2+ containing sulfuric acid solution also increased and reached 57.62% with 20 ppm Ag+ addition after 24 h. INTRODUCTION Chalcopyrite is the most important copper mineral in copper hydrometallurgy and it accounts for nearly 80% of the universal copper resource (Olvera, Rebolledo, Mora, Dixon, & Asselin, 2018). The hydrometallurgy of chalcopyrite has been intensively studied with emphasis on solving the slow dissolution kinetics of chalcopyrite in acid environment. A variety of aqueous systems, such as sulfate (Hiroyoshi, Miki, Hirajima, & Tsunekawa, 2001), chlorides (Liu, Chen, & Yang, 2017), and ammonia (Hua et al., 2018) have been studied to improve copper leaching. From another perspective, chalcopyrite leaching studies have indicated that the mechanism of chalcopyrite dissolution in acid solution is essentially electrochemical (Li, Kawashima, Li, Chandra, & Gerson, 2013). Therefore, extensive studies have recently been carried out to explain the dissolution kinetics of chalcopyrite in different media by various electrochemical techniques.

Jan 1, 2019

By Rory Cameron, Chuck Edwards

"Stringent environmental performance criteria and regulations, and the desire to minimize water use have made membrane-based treatment and separation processes an attractive option. This has lead to many advances in all aspects of the technology. Membrane separation processes have found application in sea water desalination, brackish water treatment, decontamination of ground water, and wastewater treatment. Development of membranes with better resistance to harsh feed conditions has created new opportunities for the broader application of membrane separation technologies to mineral processing streams. There are examples in mineral processing operations, including treatment of acidic drainage, pre-concentration of pregnant leaching solution in heap leaching operations, separation of acids and metals from waste streams and intermediate process streams, as well as gold and cyanide recovery from a heap leaching operation. This paper provides a brief overview of membrane technology principles, followed by a discussion of current membrane technology applications relevant to the mining and mineral processing industry. The paper further explores the potential for the application of membrane separation as an integrated component in mineral processing operations.INTRODUCTION Increased regulatory pressures, emphasis on water conservation, and scarcity of water in arid regions have resulted in substantial changes in industrial practices in recent years. As a result, many industries have become more open to adopting innovative technologies such as membrane separation. The mining industry, which is typically very conservative, has adopted membrane separation as an effective end-of-pipe solution for effluent and acidic drainage (AD) treatment; however, its use as an integrated component in plant operations has progressed more slowly. With increasingly stringent environmental regulations coupled with the desire for low- and zero-discharge operations, the use of membrane separation technology for achieving acceptable environmental performance may be unavoidable in the future. The relatively small footprint requirement, versatility, and modular construction of membrane separation units facilitate their introduction into existing processes with a suitable feed stream. Membrane separation is not a stand-alone process that provides the ultimate solution to water and wastewater treatment; however, it can often be economically added to conventional waste treatment plants to increase throughput and/or decrease contaminant output (Mortazavi, 2008). Although membrane separation technology has become an established separation technique that is widely used in drinking water production and other industries, it is still considered an emerging technology within the mining and mineral processing industry. This technology offers many potential benefits such as clean water recovery from wastewater, significant reduction of volume requiring conventional treatment, decreased usage of reagents, and acid recovery, all of which lead to increased treatment efficiencies and lower reagent consumption. This could translate to smaller and more efficient plants with lower capital and operating costs and lower environmental impacts. Plant expansion may be facilitated by incorporating a membrane separation unit operation in order to utilize existing treatment systems at higher throughputs."

Jan 1, 2012

Les Mines Inmet ? La Division Troilus exploite une mine d?or à ciel ouvert depuis 1996 et produit un concentré de cuivre. La Division Troilus est localisée à 175 KM au nord de la ville de Chibougamau? au 51 parallèle.

Feb 1, 2008

By Monique Pharand, Jeet Basi, Simon Hille

"High quality activated carbon is essential in the recovery of gold in Carbon-in-Leach (CIL), Carbon-in-Pulp (CIP), and Carbon-in-Column (CIC) circuits. Goldcorp’s Campbell complex at Red Lake Gold Mines (RLGM) experienced a period of low soluble gold (Au) recoveries during Q3 2013, during which time the processing plant saw higher than typical Au grades in the CIP tails solution stream. A technical review identified that the CIP circuit may be experiencing a carbon-fouling issue. To further understand the degree of fouling, and to troubleshoot the low recovery problem, samples of carbon were collected from the CIP, elution, acid wash, and regeneration circuits, and submitted for characterization test work. This paper summarizes the steps taken to remedy the carbon-fouling problem at RLGM resulting in increased overall Au recovery.Overview of Red Lake Gold MinesRed Lake Gold Mines is located approximately 450 kilometres northeast of Winnipeg, Manitoba, in Ontario’s western boundary region.All mining is carried out through underground operations, utilizing overhand cut and fill, underhand cut and fill, and long-hole mining methods. Ore types include: silica-replaced carbonate veins with free milling gold, siliceous replacement-type mineralization (rich with arsenopyrite) marginal to veins, broad disseminated sulphide mineralization along major shears, and some minor sulphidized chemical sediment-hosted ore. The operation is supported by two milling complexes: Red Lake, and Campbell.Process DescriptionThe Campbell processing plant's main unit operations consist of grinding, gravity concentrating, flotation, autoclaving, leaching, carbon-in-pulp (CIP), carbon elution and reactivation, electro-winning, bullion smelting/refining and cyanide destruction, and concentrate handling. A schematic of the plant flowsheet is shown in the figure below.BackgroundHigh quality activated carbon is essential in the recovery of gold at many CIP/CIL/CIC processing plants. At RLGM, gold-bearing ore is milled and cyanide is added to leach the gold from the solids into solution. The dissolved gold then comes into contact with activated carbon, and adsorbs onto its highly porous surfaces. Gold is then recovered by separating the activated carbon from the main slurry for further refining. As such, the characteristics and quality of the activated carbon have a significant and direct impact on overall gold recovery."

Jan 1, 2016

By Charles Knilans, Tassos Grammatikopoulos, Nicole Hoffmann

"Twin Metals Minnesota LLC, (TMM) has recently completed a prefeasibility study evaluating the development and operation of an underground copper (Cu), nickel (Ni), platinum (Pt), palladium (Pd), and gold (Au) mining project on the Maturi deposit in northeastern Minnesota.The Maturi deposit is a magmatic Cu-Ni-sulphide deposit occurring along the basal contact of the South Kawishiwi intrusion, comprised of heterogeneous troctolites to gabbros forming a tabular body designated the BMZ (basal mineralized zone). These rocks provide the major gangue mineralogy (plagioclase, olivine, and clinopyroxene) with local, minor rock-forming orthopyroxene, biotite, magnetite, and ilmenite. Altered silicates exist within local fracture and/or alteration zones, which are commonly associated with minor faults in the regional area. The Maturi deposit is comprised of four main mineralized zones within the BMZ, referred to as Stage 1, Stage 2 (S2), Stage 3 (S3), and Upper Heterogeneous. Chalcopyrite, cubanite, pentlandite, and pyrrhotite are mainly hosted within the S2 and S3 units, with talnakhite frequently occurring within the S3 unit.A cross-discipline approach combining geology, geochemistry, metallurgy, QEMSCAN™ mineralogy, and mine planning has been implemented to develop a preliminary geometallurgical model and life of mine metallurgical performance forecast. This paper provides an overview of the methods that were used to develop the model and forecast, and discusses the advantages of such a model in project development and evaluation.INTRODUCTIONThe TMM Project proposes mining a copper-nickel-palladium-platinum-gold-silver (Cu-Ni-PGM) magmatic sulphide deposit situated in the Duluth Complex of northeastern Minnesota, USA. The prefeasibility study proposes a 45,000 million tonnes per day mine and concentrator facility to produce two saleable concentrates. The mine will access two separate deposits, Maturi and Maturi Southwest. Saleable concentrates are the final products of the sequential flotation plant where a high grade Cu concentrate is produced followed by a Ni concentrate."

Jan 1, 2015