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By D. B. Felsher

"Lakeshore Gold’s Bell Creek Mill is located in Timmins, Ontario. The mill has been in operation since 2009 and has undergone several small expansions since then. In 2012 - 2013 the first major mill expansion was commissioned raising the mill capacity from 2,000tpd to 3,150tpd. This was done through the installation of a new ROM ore truck dumping facility, jaw crusher, ore storage dome, SAG mill, leach tank, CIL tank, and electrowinning cell. This paper will cover the equipment installed to raise the tonnage as well as the commissioning of the new equipment including problems encountered and how these problems were solved.IntroductionLake Shore Gold acquired the Bell Creek Mill, along with the Bell Creek Mine, from the Porcupine Gold Mines Joint Venture, a joint venture between Goldcorp Canada Ltd. and Kinross Gold Corporation, in December 2007.The Bell Creek mill, which processed ore from the Bell Creek Mine has consistently achieved recoveries of over 95%, is a conventional gold mill circuit, involving crushing and two stage ball mill grinding, gravity and leaching, followed by Carbon-In-Pulp (CIP) process for gold recovery. The facility had been placed on care and maintenance in 2002. At the beginning of 2009, the mill had been refurbished with an initial capacity of 800 tonnes per day and was subsequently refurbished to a capacity of 1,500 tonnes per day near the end of the third quarter of that year. The Mill was then expanded in 2010 to a capacity of 2,000 tonnes per day.In late 2011, the Company commenced a 50% expansion of its milling facility, from a processing capacity of 2,000 tonnes per day to 3,150 tonnes per day. Phase 1 of the expansion, which mainly involved enhancements to the solution circuit (“back end”) and increased the mill’s capacity to 2,500 tonnes per day, was completed at the end of 2012. Commissioning of Phase 2 of the expansion, to a capacity of 3,150 tonnes per day, commenced at the end of July 2013."

Jan 1, 2015

By J. Budac, E. Krause, C. L. Stewart, D. Wrana, S. W. Laundry

"As part of an over-all arsenic management strategy, Inco has developed a novel process that converts a by-product high moisture copper/arsenic sulphide precipitate into a crystalline copper arsenate suitable for the manufacture of wood preservation chemicals.The copper/arsenic sulphide precipitate is atmospherically leached with oxygen and sulphuric acid, producing a crude (blue) copper arsenate precipitate, elemental sulphur, and a copper and nickel containing solution. The blue copper arsenate is dissolved with sulphuric acid, the molar Cu/As ratio is raised to 2, and a crystalline copper arsenate (olivenite) is precipitated by the addition of sodium carbonate. Dissolved copper is recovered using metallic nickel (or matte) and elemental sulphur, to produce a low-moisture (low-arsenic) precipitate suitable for standard nickel-copper processing.The process was successfully piloted at Inco's Manitoba Division between September 1990 and June 1991. The copper arsenate product typically analyzed 43% Cu and 25% As, and the moisture content was about 10%."

Jan 1, 1995

By I. M. R. Duarte, J. A. Rodrigues-Carvalho, F. R. S. Rosa, A. B. Pinho

"This paper aims to contribute to the knowledge of the mechanical properties of the shales and greywackes which constitute the flysch-type deposits of the Baixo Alentejo Flysch Group, in the south of Portugal. These formations are flysch-type deposits constituted by sequences of usually thick greywacke beds alternating with thin shale beds, which include sometimes intercalations of conglomerate beds. All the sedimentation of these flysch formations was controlled by tectonics. At the same time, should have occurred along with the first Hercynian deformation phase, a low-grade metamorphic event (chlorite zone), that affected these flysch deposits. This study highlights the influence of anisotropy and heterogeneity of these flysch rocks on their physical and mechanical characteristics. The anisotropy verified in some physical properties and on mechanical properties, due to the foliation makes difficult the sample preparation for the laboratory tests. Besides, it induces a scattering of the properties values measured, as for example, the strength and the deformability. The heterogeneity is related to the main features of these geological formations, which are constituted mostly by thinly stratified greywackes and shale beds, which sometimes may affect the results of the laboratory tests making them less representative. The study is made by using both shales and greywackes that constitute these flysch-type deposits in order to evaluate their geotechnical properties, mainly of the shales. Samples of these two rock materials, are tested accordingly a laboratory testing programme, which includes which included mineralogical analysis (X-ray diffraction), physical tests (bulk density, porosity, and void index) and mechanical tests (uniaxial compression, and deformability tests). INTRODUCTIONOne of the factors that most influence the geomechanical behavior of rocks, as well as rock masses is the anisotropy. The word anisotropy comes from two Greek words ""anisos"" (meaning uneven) and ""tropos"" (meaning direction). A body or material is considered to be anisotropic, where the same property has different values depending in which direction it is measured, therefore, an anisotropic material is one whose magnitude of the properties depends on the direction in which these are studied or measured. Otherwise, it is about an isotropic material. However, the fully isotropic materials are quite rare in nature."

Jan 1, 2015

By Marc Ruest

A new instrumented cable bolt has been developed by the National Institute for Occupational Safety and Health at the Spokane Research Laboratory in Spokane, WA. Although various instruments are available to measure load distribution and magnitude along a grouted cable, this instrument is innovative in that it uses strain gauges internal to the cable as load-measuring sensors. The instrument has been successfully tested in the field at FMC?s Granger Mine, Meikle Mine, and Getchell Mine. A ?split-pipe? laboratory pull test was performed on each of three cable bolts instrumented with the new device. Each test consisted of grouting a 1.83-m-long cable in two 0.91-m-long sections of schedule 80 pipe. A numerical analysis was then performed in which laboratory boundary conditions were simulated and model properties derived from textbook guidelines. The loads calculated by the model were then compared to the measured loads.

May 1, 2002

By Alex Cormode, Carlos Perucca

"Sylvinite ore from the Saskatoon area typically contains about 5% insolubles, occurring as clays and carbonates. These insoluble slimes must be removed sufficiently well to permit an efficient subsequent potassium chloride flotation, due to their high adsorptive capacity for amines used as potash collectors. The insolubles are liberated from sylvinite by high attrition scrubbing in a slurry. The liberated slimes are separated by multistage cycloning or by a selective flocculation-flotation process.An outline of the potash processing operations at Agrium Vanscoy Potash Operations is given, emphasizing the insoluble slimes froth flotation separation process. This process was originally implemented at the Agrium plant in the mid- 1970's and replaced a hydrocyclone system.IntroductionAgrium Vanscoy Potash Operations is located 40 Km southwest of Saskatoon, almost midway between the communities of Vanscoy and Delisle. Processing operations started in 1969, and the annual production capability was subsequently increased to the current 1.8 MM tonnes per year of muriate of potash.The mining operation at Agrium Potash which was described in a paper by Jones and Pruggerl , is done underground using four large continuous double rotor boring machines for the main production with development done by heliminers. Annual ore production is 5.5 MM tonnedannum. Ore is hoisted 1,100 m to surface for processing."

Jan 1, 1999

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 Kallioinen Jouko

"Advanced Flotation Technology is the application driven design of Don-Oliver flotation cells to achieve the optimum performance for each type and grind of flotation. Optimum performance is the combination of both recovery and selectivity.Optimized performance is the combined product of optimized mixing and effective froth removal. Optimized mixing is applied to roughers, scavengers, cleaners and specialty cells such as those to float hydrocyclone underflows in both primary and regrind circuits in order to reduce overgrinding. Effective mixing for fine material is easy, but overmixing reduces selectivity in frothbed.Selectivity in flotation is an important target, especially when treating complex ores, and parameters in frothbed have been examined to improve the separation of minerals and eliminate circumstances that reduce separation rate.Advances in process control have been achieved with expert controls and instructive operator information data. This has gained a higher degree of understanding of cell operation and ore type being processed to be used in future process development work. Excellent results of this Advanced Flotation Technology have been achieved and designs through 7000 cu ft (200 m3) are currently available for high capacity concentrators. This paper will detail how flotation cells are more responsive to the exact requirements of the duty specified."

Jan 1, 2000

By Å. Kruukka, H. F. Broicher

The iron ores of the Kiruna mine in Sweden are of exceptional quality except for the phosphorus content in certain zones of the orebody. The prevention of mixing ores high in phosphorus with those low in phosphorus has always been of significant economic importance. The ongoing introduction of tele-mining and automatic haulage by LHDs requires new means in the field of quality control underground, as the experienced miner as well as the underground laboratory assistant no longer are involved in the process. As of 1998, LKAB has been testing prototypes of LIF (laser-induced fluorescence) analyzers for non-contact and real-time measurement of the phosphorus content of ore being transported by LHDs from the stopes to the respective ore pass assigned to a certain ore quality. The principles of the analysis of laser-induced fluorescence, the different test phases and results are described and conclusions made. With bulk sorting of ore underground, the mining engineer supports the efforts of the metallurgist in the processing plant.

Jan 1, 2002

Safe underground mine backfilling with hydraulic fill requires efficient fill drainage and stable fill retaining walls or bulkheads. If any or both the above two requirements are not satisfied, such a backfilling operation creates unsafe conditions and may lead to backfill retaining wall failures. Mine backfill retaining wall failures are always associated with economic losses, fatalities and interruption to mine production. Mining industry wants to either reduce or eliminate these fill retaining wall failures. The fill retaining wall failures could be effectively avoided through the use of fibre reinforced shotcrete fill retaining walls and engineered drainage systems through the retaining walls. This paper presents the experience of the author in developing, implementing, and monitoring several hundred fibre reinforced shotcrete fill retaining walls at a mine in Australia with the highest safety standard. The details on the mine backfill drainage system and fibre reinforced shotcrete fill retaining wall designs are also presented.

May 1, 2007

By J. A. Meech, G. R. Baiden

"A dynamic simulation of a mine-mill complex has been conducted using networked microcomputers (IBM PC/AT and IBM PC/XT). These models allow simultaneous operation of an open pit using shovels and trucks, a primary crusher, and a secondary crushing plant. Each process transmits information via the network, linking all operations together. The effects of blasting, ore quality, equipment utilization and configuration on productivity can be studied either interactively or from a report listing at the end of each shift. Programs are menu driven leading the user through the decisions required in day to day operations. The mine-mill simulator is currently being used as a teaching tool at Queen's University to provide senior mining and mineral processing engineering students with an experience and appreciation for the operating problems across the mine-mill interface. The need for coordination and close communication between the mine and mill can be aptly demonstrated using these models. The simulator could be used to contribute to the training of operating personnel in a real mining operation. INTRODUCTIONThis paper describes a computer simulator that is capable of showing the interactions and operating strategies between a mine and a secondary crushing plant. The simulator uses two models developed at Queen's University; one for open pit mining and the second for secondary crushing. PITSIM is a dynamic shovel/truck haulage model origin2lly developed by P.D.D. Chick (1) and K.G. Fytas (2) to solve shovel/truck scheduling problems. CRUSHSOFT is a dynamic secondary crushing plant model developed by R.J. Tucker (3) and C.A. Harris (4) to study alternative operating and control strategies in a crushing plant."

Jan 1, 1987

? Founded In 1953 ? Mining growth of 83% since 2007 ? We produced over 1 million ounces of Au in 2012 ? We Forecast of 20% Au production in 2013-2015 ? We have paid a dividend 31 years consecutively. Terry Reid ? 1992-93 Electrical Technical, College ? 1994-95 On the job placement College ? 1998 ? Licensed Millwright, ? 2005-12 ? Maintenance Reliability Planner ? 2012- Present Business Process Owner

Aug 1, 2013

By P. Radziszewski

"The comminution energy curve is a profoundly simple graphical technique that displays detailed operating efficiency information for industrial comminution processes. The database underlying the methodology has recently more than doubled, to now contain a substantial fraction of the international comminution output (1.7 billion tonnes of rock per year) across more than 8 major commodities. This increase has deepened the analytical capabilities and effectiveness for assessing comminution circuit performance in relation to comparable operating mines. This paper will explore how the energy curve methodology can be used to examine the ability of stirred mill technologies to increase efficiency.Specifically, this paper explores how the energy curves methodology can be used to present energy efficiency gains achieved at three mines employing a stirred mill technology under different duties. The first of these cases studies was conducted by Rosa (2014) who compared the performance of two ball mills operating in parallel with a Vertimill in the regrinding circuit at the Samarco Iron project in South East Brazil. The Vertimill was found to achieve the same product specification while consuming 40% less energy. Brissette (2010) investigated the impact of grinding media on the performance of both ball mills and Vertimills. The energy savings achieved varied from 10% to 40% for the ball mills and 30% to 60% for the Vertimills. Lastly, Bergerman (2012) investigated the operating conditions of the Sossego regrind circuit from 2006 to 2011 against design specifications and laboratory testing. The operating work index of this circuit varied from 5.2 kWh/t to 44 kWh/t over this 5 year period. The full suite of energy curves"

Jan 1, 2016

By M. C. Villeneuve

A numerical modelling approach was developed to explicitly simulate geomechanical characteristics of intact rock: mineralogy, grain size and fabric. The approach involved creating a representative constitutive model for each of three common rock-forming minerals: mica, quartz and feldspar. The constitutive models developed are valid within the low confinement realm of excavation boundaries, where tensile fracture processes dominate. The mineral types were assigned to numerical elements, which were associated with each other through an algorithm created in a finite difference model, FLAC 2D (Itasca 2007a), to simulate real crystal geometries and orientations. The numerical models were used in a parametric investigation of the geomechanical characteristics and compared with published observations of the rock yielding process in laboratory testing. This approach has allowed the explicit grain-scale investigation of the impact of geomechanical characteristics on rock yielding at low confinement, leading to an improved mechanistic understanding of excavation-scale rock yielding processes at excavation boundaries.

May 1, 2009

By Manqiu Xu, Songtao Yang, Zongfu Dai, Robert Pelton

"Hydrophobic polystyrene nanoparticle suspensions were evaluated as potential flotation collectors for pentlandite. Experiments involving both clean model mineral suspensions and complex ultramafic nickel ores confirmed that conventional water-soluble molecular flotation collectors such as xanthate could be partially or completely replaced by hydrophobic nanoparticle flotation collectors. The ability of nanoparticles to induce flotation was demonstrated by floating hydrophilic, negatively charged glass beads with cationic polystyrene nanoparticle collectors. Electrostatic attraction promoted the spontaneous deposition of the nanoparticles on the glass surfaces raising the effective contact angle sufficiently high to promote the adhesion of beads to air bubbles. As little as 10% coverage of the bead surfaces with our most effective nanoparticles could promote high flotation efficiencies, whereas conventional small molecular flotation collector requires ~ 20% or higher coverage for a good recovery. Surface functionalized nanoparticles enhanced the ability for nanoparticle collectors to selectively deposit onto surfaces of the desired mineral particles in the presence of gangue. For example, poly (styrene-co-vinylimidazole) nanoparticles were designed to selectively deposit onto nickel mineral (pentlandite) in the presence of Mg/Si slime. Flotation tests of ultramafic nickel ores at Vale with these nanoparticle collectors have shown improvements in both pentlandite recovery and selectivity. On-going work includes attempts to identify specific applications where nanoparticle flotation collectors might be cost effective.INTRODUCTION Most mineral processing operations include multiple stages of froth flotation to concentrate and isolate the desired product. Before flotation, chemical collectors are routinely added to ground ore slurries, selectively binding to mineral-rich particles, increasing their hydrophobicity thus promoting selective flotation. (Fuerstenau, Jameson, & Yoon, 2007) Conventional collectors are surfactants with a short hydrocarbon tail and a head group, such as xanthate. A typical conventional collector is potassium amyl xanthate (PAX), which is a small molecule with an extended molecular length of about 1 nm. Critical characteristics of a good collector include the ability to selectively adsorb onto desired mineral surfaces and to lower the water/mineral surface energy. Despite the extensive role of flotation in mineral processing, some ores are difficult to process by flotation. For example, ultramafic nickel sulfide ore containing both valuable pentlandite and large quantities of unwanted Mg/Si slime [primarily serpentine, (MgFe)3Si2O5(OH)4] responds poorly to flotation. (Mani, Xu, Quinn, & Stratton-Crawley, 1997) Fibrous hydrophilic Mg/Si slime usually masks the surface of pentlandite (known as “slime coating”) due to electrostatic interaction (Edwards, Kipkie, & Agar, 1980) and dramatically depresses pentlandite flotation. Consequently, new approaches are required for processing these difficult ores."

Jan 1, 2012

By Sylvie Brassard

Available information ?? InfoMine: mineral properties ?? Metals Economics Group: budgeted exploration expenses ?? MineScan: Canadian and American Mining Companies ?? Statistics Canada: Canadian Direct Investment Abroad, by Sector in the world OR all sectors by Country

May 1, 2008

By Jan E. Nesset, Julie Fournier, Jorge Torrealba, Colin Hardie

"Gas dispersion studies have been used to benchmark and optimize plant flotation performance for more than a decade, although this technology is not as widely in use as it likely should be based on the significant improvements that have been reported. Part of the reason may be a general lack of awareness within the industry of just what these improvements have been. This paper reviews a number of the reported case studies, groups them into categories of improvement, and draws some general conclusions. The paper will be of interest to plant engineers and technology providers seeking new approaches and tools for improving their own and clients’ processes.INTRODUCTIONThe sector of flotation hydrodynamics that is now known as gas dispersion technology, and the corresponding terminology, had its beginnings in the 1980’s and early 1990’s in the laboratories of McGill University where the students of Prof. J.A. Finch and Dr. C. Gomez conducted studies of gas holdup, superficial gas rate and water recovery on laboratory flotation columns (Laplante et al., 1983; Xu et al., 1991;, Banisi and Finch, 1994; Finch et al., 1999; Nesset, 2011). Sensors were developed for gas holdup (eg), gas rate (Jg) and bubble size (Db) distribution (Tavera et al., 1996: Finch et al., 1999; Dahlke et al., 2001; Chen at al., 2001; Hernandez-Aguilar et al, 2002, 2005). The sensor measurements were rapidly adapted for use in mechanical flotation machines in plant environments (Gomez and Finch, 2002; Gomez et al., 2003; Cooper et al, 2004; Torrealba-Vargas et al, 2004; Nesset et al., 2007). Somewhat parallel developments were being conducted by Gorain and colleagues at the University of Queensland’s JKMRC on pilot and industrial flotation machines using the McGill approach but utilizing alternate sensor designs for eg, Jg and Db (Gorain et al., 1997, 1999; Schwarz and Alexander, 2006) to link flotation kinetics to bubble surface area flux (Sb). Early industrial applications were those led by the university teams from McGill (Canada), the JKMRC (Australia) and the University of Santa Maria (Chile) at plants in North and South America, Australia, South Africa, Asia and Europe. Industrial organizations that brought the technology on-board in the early 2000’s included Teck Resources (then Teck Cominco), COREM, Vale (then Inco), Anglo American Platinum. Several of the major flotation cell manufacturers also purchased the McGill bubble viewer technology for their own equipment studies. The sensors have continued to evolve with multiple and continuous measurement of Jg (Torrealba-Vargas and Finch, 2006, Bartolacci et al., 2008), gas holdup by acoustic means (O’Keefe, 2007) and a combined Jg-Db device called the Anglo Bubble Sizer (Harbort and Schwarz, 2010). A review of the gas dispersion technology use and development have been provided by Gomez and Finch (2002), Harbort and Schwarz (2010) and Nesset (2010)."

Jan 1, 2015

By M. J. Beus

Many mines in Canada, the United States and South Africa are reaching the hoisting limit. Very little payload will be possible without compromising safety due to the excessive weight. It has been suggested (DeLorme, 2000) that one of the most attractive concepts to enable deeper hoisting is to reduce the allowable factor of safety in the wire rope. Researchers at the Spokane Research Lab are developing new technology to improve hoisting safety and productivity by providing new monitoring and analytical tools. A Shaft Conveyance Monitoring System (SCMS) has been developed which determines hoist rope end load, true conveyance position and acceleration, and rope safety factor, as well as other hoist operating parameters. This information is transmitted to the hoist operator display 20 times per second. Recent field measurements on 45 mm (13/4 in.) diameter hoist rope indicate that dynamic forces during loading of a 9000 kg (10 ton) skip could exceed the safety factor of the rope. To improve on the current understanding of the mechanical behaviour of hoist ropes, and to help interpret the results from field-testing of the SCMS, a new approach to computer modelling of stranded wire rope is also being developed. Particle Flow Code, PFC3D (Itasca, 1999), is used to simulate the structural behaviour of wire rope and the interaction between individual strands when the rope is subjected to static and dynamic end loading. Details of the SCMS, field results from the measured rope loads, and the results of numerical modelling on the wire rope will be discussed.

Jan 1, 2002

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

"The Dumont deposit is a large (1066 Mt probable reserve) low grade (0.27% nickel), nickel sulphide project located in the Abitibi region 25km west of Amos, Quebec. Royal Nickel Corporation acquired the project in 2007 and has since taken the deposit through pre-feasibility. And updated, revised pre-feasibility was released in July 2012.The disseminated nickel sulphide and alloy mineralization is hosted within the serpentinized dunite subzone of the Dumont Sill; a differentiated, pervasively serpentinized, ultramafic sill of komatitic affinity. Pentlandite, heazlewoodite and awaruite are the dominant nickel-bearing, metallic phases and can be recovered by conventional methods (flotation, mag separation). Non-recoverable nickel is also present within the silicate matrix of the serpentinized dunite and is locked in serpentine (Fe and Mg-rich variants) and minor olivine.A detailed mineralogical program including 1097 QEMSCAN® samples and 4300 electron microprobe points were undertaken to increase the understanding of the nickel deportment in the various recoverable and non-recoverable phases in a spatial context across the deposit. Eighty-three (83) metallurgical tests performed under a standard procedure have linked the mineralogy to metallurgical performance. This has allowed the creation and modelling of geometallurgical domains on a block by block basis to understand the recovery variation and metallurgical performance throughout the deposit. Understanding the spatial variability of Ni deportment in recoverable and non-recoverable phases through mineralogy is the key to understanding metallurgical performance thus, unlocking the value of the Dumont deposit and other large tonnage low grade ultramafic nickel deposits."

Jan 1, 2013

By M. R. Dion, K. Frenette, R. K. Jonas, S. Simard, F. Robichaud

"In 2011, a site study indicated that the application of Honeywell’s Multivariable Predictive Control Technology (MPC) to the Goldex processing facility would provide significant opportunities for improvement. Grinding MPC was implemented in the SAG Mill in June 2015. This pilot application, called Phase 1, featured one of the first Multivariable Predictive Controllers to be installed in a Canadian mineral processing plant. Since the implementation of MPC, gold recovery from the gravity circuit has increased. MPC contributed to a decrease in flotation feed particle size (120 to 112 µm) and an increase in the SAG feed tonnage (8.5% increase). MPC also increased and stabilized the % solids of the SAG feed, which can have an impact on cost reduction (mechanical maintenance). Additionally, MPC increased productivity, providing grinding operators with more time to perform other tasks. Further anticipated benefits include the standardization of the grinding circuit operation from one team to the next, thereby minimizing circuit disturbances resulting from different operating philosophies. This paper will discuss the advanced control project development and justification, the technology and rapid implementation process, the performance results and the benefits obtained.IntroductionGoldex is an underground mine located near Val-d’Or that is owned and operated by Agnico Eagle Mines Limited (AEM). Between 2008 and 2011, mining focused on the Goldex Extension Zone (GEZ). In 2011, the project was halted due to geotechnical problems; operations ceased until late 2013. Goldex operations resumed in September 2013 with the M and E zones, for which there were 0.7M gold ounces of proven and probable reserves, 2.1M ounces of measured and indicated resources and 1.2M ounces of inferred resources, totalizing 4M ounces. Life expectancy was extended until 2024."

Jan 1, 2017