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Project Located in northwestern British Columbia 70km West of Cassiar Highway Galore Creek Project and Road Access Corridors Designated For Mineral Development in Stikine-Cassiar Land Resource Management Plan (LRMP)Approved in 2000Strong BC Government, local community and Tahltan First Nation Support for Project

May 1, 2006

By Hans von Michaelis

"INTRODUCTIONThe renaissance in gold and silver recovery technology has continued to unfold and it is appropriate to review some of the useful new technologies as well as try to identify some of the industry's future needs and frontiers.The remarkable strengthening in the US dollar has resulted in a relatively low gold price in US Dollars of around $310/oz at the time of writing and silver at $6.25/oz. This general softening in the dollar prices and the recent confusion as to environmental compatibility of cyanidation tailings and effluents, has led to a slowdown in announcements of new operations. Another reason for the slackening off in the USA is that in the past few years a large part of the capital has come from oi I and gas companies that now seem to be losing interest in mineral ventures, and foreign investors for whom the dollar is becoming out of reach. In the author's opinion this represents an unprecedented window of opportunity.Elsewhere in the world where local currencies have weakened, the price of gold is at or close to its all time high.For example, in South African Rands, the gold price was R571.00/oz when the rand was US$1.47 and the gold price reached US$800. Now at US $309/oz and with the Rand at US$0.51 = Rl .00, the local gold price is R600. The price of si Iver in Mexican pesos is not much less than it was when silver reached US$50/oz. Gold, and silver prices in local currencies outside North America are still buovant and at levels where additional investment in new projects is more encouraging.Even in Canada where the dollar is worth about US$0. 75, this provides a smaller but significant cushion compared with US operations. Considering the present strength of the US dollar and even the Canadian dollar relative to many other gold producing countries, there should be significant investment opportunities at today's prices. Mining companies have started to descend on Brazil, for example, where in a matter of just a few years annual gold production has increased from 10 to 70 tons. In South Africa, a Canadian company backed by Swiss financing has been able to take over a Witwatersrand gold mining operation and is installing a huge new tailin9s retreatment plant to process about 1 million tons per month of tailings."

Jan 1, 1985

By Mostafa Benzaazoua, Bruno Bussière, Philippe Poirier, Denis Bois

"Environmental desulphurisation is an attractive alternative for the management of acid generating tailings. Non selective froth flotation is the most commonly used method to produce desulphurized tailings, as shown from many previous works (McLaughlin and Stuparyk, 1994; Bussière et al., 1995; 1998; Benzaazoua et al., 2000a,b; 2002). This process can reduce the volume of problematic tailings to manage, by making a sulphide fraction concentrate. The desulphurized tailings can then be used as a moisture retention layer in a cover with capillary barrier effects to prevent acid mine drainage.In this paper, the authors present the results from different laboratory and pilot scale flotation tests which confirm that low sulphide, non-acid generating tailings can be produced by froth flotation. It is also demonstrated that the sulphide concentrates obtained from desulphurisation, when mixed with binders gave good long term results in terms of mechanical behaviour, thus demonstrating that the sulphide fraction can be used for paste backfill material. From previous work (Bussière et al. 1998, 1999) on the evaluation of the operating and capital costs of the desulphurisation process for different ore types, the use of desulphurized tailings to create a dry cover was then studied for several scenarios. The desulphurisation process was compared with other technologies (underwater disposal, engineered soil cover) currently used to prevent acidic drainage (AD) for a new mining operation and the advantages and disadvantages of desulphurisation are presented as well as the costs of this method of AD prevention.INTRODUCTIONThe principal environmental problem of the mining industry today is the generation of acidic drainage (AD) resulting from the natural oxidation of the sulphides in mine tailings. This phenomenon involves the generation of acidity which increase the amounts of toxic metals in the waste water released into the environment by a mine. The environmental impact of the AD has been described in detail in previous work (e.g. Down et Stocks, 1977; Ritcey, 1989; Gray, 1997; Ripley et al., 1996; Aubertin et al., 2002)."

Jan 1, 2004

By S. Junnikkala, K. Föhr

"Experiments were performed with plant feeds with a continuous 1,8 m3 cell at Pyhasalmi mine with Cu flotation feed in order to test the applicability of the bubble surface area flux as an indicator of the flotation rate constant. It was found that bubble surface area flux could not predict the rate constants of coarse Cu containing fractions. In the middle size fraction, the correlation coefficient in the rate coefficient estimation was higher but not statistically significant. Only the fine fraction showed a linear relationship with a moderate correlation coefficient.The bubble surface area flux was shown not to be a function of the impeller velocity above a threshold value. The flux was an almost linear function of the superficial gas rate enabling to use the superficial gas rate instead of flux if the operation of an existing cell is to be estimated.INTRODUCTIONBubble area flux seems to offer a simple way of modeling flotation. It relates the flotation rate constant with the bubble surface area flux by a simple linear equation. Due to this, there has been a considerable interest in using the bubble area flux for flotation computations. It has even caused claims that a cell producing a high bubble surface area flux automatically produces a high rate constant and therefore a high recovery.This paper discusses some of the assumptions of the relationship and gives some plant results during two sampling campaigns.The bubble surface area flux s b is describing the area of bubbles available for flotation in a cell per unit area. The bubble surface area flux is related to the superficial gas rate J, by the Sauter mean diameter as follows"

Jan 1, 2001

By J. K. Gowans

"INTRODUCTIONTo bring a mining property into production in the Canadian High Arctic a company must deal with the harsh environment, the short shipping season and the high cost of labour. In trying to minimize the effect of these factors, the concept of a barge-mounted process plant was investigated as an alternative to the conventionally built concentrator. Cominco's previous experience gained at the Black Angel Mine on Greenland's west coast suggested that this would be a practical alternative.The normal shipping season at Little Cornwallis Island is approximately six weeks long, from mid-August to the end of September. All equipment and materials must be delivered during this small ''shipping window."" The logistics problems are enormous; if the conventional approach had been used the major process equipment would have been delivered to Little Cornwallis Island at the same time as the completed barge actually was! Construction would also be starting at the start of the worst climatic conditions, the Arctic winter. Nine months production was gained by opting for the ""Barge"" approach.What the Arctic winters do to the shipping season, so do they affect the productivity and the cost of labour. Construction labour must come from southern Canada. Thus higher transportation costs and higher wage rates, with more overtime and incentives, increase the labour costs to approximately 50% over normal southern rates. Couple these rates with the lower productivity involved with men working in the extreme cold temperatures and the net effort is worth avoiding. A process plant being constructed in Southern Canada can take advantage of more accessible labour at lower costs, increased productivity and a faster construction schedule. The barge concept must still deliver the equipment and materials during the ""shipping window"" but it can in the completed form."

Jan 1, 1983

By Bern Klein

Motivation for Improved Energy Efficiency in Mining ? Canada potentially adopting Greenhouse Gas Emissions and Intensity Legislation in 2013 ? BC -Climate Action Plan and Energy Conservation Agreement in 2008 ? BC Energy Plan 2007 -BC Hydro is mandated to save 50% of new load growth ? TSM Initiative -Energy Management, Energy Reporting, Setting Energy Targets, GHG Management BC MOU for Energy Conservation Agreement -MEMPR, MABC, BC Hydro

May 1, 2010

By J. H. Archibald

"IntroductionShot-saws are used for sawing rock throughout the dimension stone industry especially in granite quarry mills. Shot-saws, as currently designed, have an inherent wear problem which leads to slow cutting rates and repetitive blade changes which consumes much time. Because the saw blades are made from steel the abrasive shot used with them is limited to a certain hardness which effects the over-all efficiency of the sawing operation. Suggestions are made toward optimization of blade design and the sawing process. Blade DesignA common steel blade design is shown in Figure I. Note the perforations in the blade. These perforations or holes in the blade serve two or three purposes. The most obvious reason is to allow the abrasive shot a pocket in which to collect at the bottom of the blade, so that it can be distributed from these pockets into the cutting zone underneath the blade. The abrasive is fed to the saw in a slurry and usually comes in from the top. The blade must then cut a kerf wider than itself in order that the abrasive grains have a path leading from the top of the blade, down along its sides, and finally reaching the pockets and cutting zones. This circuitous path followed by the abrasive leads to side wear on the blades and high friction which can lead to blade buckling in severe cases. However, the fluidized path of the abrasives down the sides of the blade serves another purpose which is a positive gain if conditions are properly controlled. The abrasive slurry interacts with the perforations of the blade, the blade itself and the rock. This gap and the perforations in the blade, which are fluid filled, are sites of constant shearing motion. Eddy currents form in these gaps and pockets which tend to stabilize the blade by setting up balanced hydrodynamic forces which otherwise might not form in a non-perforated blade. A stable blade produces a more uniform cut in the rock. The third and final reason for the perforations are to allow the blade to wear in such a fashion that new pockets are always being formed and, consequently, new cutting surfaces between these pockets are also formed."

Jan 1, 1993

By Pavel Vasak

The Laurentian University Virtual Reality Laboratory (VRL) has provided a unique platform for the development and testing of novel seismic and microseismic data processing and visualization technology. In collaboration with Vale?s Creighton Mine, the technology was implemented at the mine site and consists of a VRL system and site calibrated Seismic Excavation Hazard Map (SEHM) software. The SEHM was developed as a practical solution for the mine operator to identify areas of elevated, active rock mass damage processes caused by recent mining activity. This paper is a pictorial representation of the 3D stereoscopic demonstration of the Creighton Mine seismic data distribution and interpreted SEHM for the first quarter of 2009. A live demonstration is scheduled at the Laurentian University VRL as one of the conference field trips. The demonstration highlights the technology transfer of research concepts into a near-real-time excavation hazard system that utilizes the key aspects of virtual reality technology; the ability to integrate large datasets (geology, mine excavation, (seismic) monitoring data, production scheduling, stress model, etc.); the ability to manipulate and visualize large datasets in both space and in time (mining sequence); and the ability to review the datasets by a group of experts in an immersive (3D stereoscopic), collaborative environment to better understand the processes and context of the mining-induced seismicity and evaluate potential risks to the mining operation.

Oct 1, 2010

By Corby G. Anderson

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

Jan 1, 2006

By J. Don Scott

Analytical predictions of the rate and magnitude of settlement of deposited oil sands tailings slurries generally overestimate how fast pore pressures will dissipate. Field deposits of nonsegregating tailings to mature fine tailings show continued high pore pressures near the surface which impede surface reclamation. In geotechnical analyses which predict the consolidation behavior of soft soils a finite strain theory is used. Effective stress-void ratio and void ratio-hydraulic conductivity relationships determined from laboratory large strain consolidation tests, are used in the finite strain predictions. This theory, however, cannot predict the full range of sedimentation, consolidation and pore pressure dissipation which occurs in large scale deposits of thixotropic tailings slurries. A new large strain consolidation model which assumes that the creep rate of the slurry exceeds the pore pressure dissipation rate is being investigated. This model is relevant for rapidly deposited, low permeability thixotropic slurries where the upwards drainage path increases by several meters a year, such as, in oil sand fine tailings ponds and nonsegregating tailings deposits. The model will be verified by analyzing the 10m high column of fine tailings at the University of Alberta which has been monitored for over 20 years and in which the excess pore pressures are still very high.

May 1, 2004

By J. A. Meech, R. J. Tucker

"A dynamic computer model has been developed to simulate the operation of ore crushing plants. The model was created in a general form to allow imitation of a wide variety of secondary crushing circuits with only minor program modifications. The system can be run on either a microcomputer or a large time-sharing main frame computer as required.The size reduction and separation characteristics of crushers and screens are based on standard manufacturers' design and performance data. These calculations are isolated within various subroutines to facilitate tailoring of the model to emulate any particular plant of interest. Input and output data are presented in a variety of formats. Crusher, screen and conveyor amperages and surge bin levels can be presented in a tabular form along with appropriate alarms arising from improper circuit operation or process interruptions. Graphical representation of the circuit together with strip chart data output are features of the system when operated in a microcomputer environment.The program is currently being used at Queen's University as a teaching aid to demonstrate plant operating characteristics, control strategies and design concepts. The acceptance of, and reaction to the program at this level indicates a good potential for it to provide a valuable tool for operator training."

Jan 1, 1985

By C. J. Martin, M. P. Hay

"A methodology was developed in the mid-1980’s to predict plant performance from standard laboratory flotation tests. The technique is based on a simple, empirical kinetics model, and is tailored for use by the practical metallurgist.To date the performance of more than 20 flotation plants has been predicted, including copper, lead, zinc, phosphate, pyrite, graphite, cassiterite, platinum, nickel and various slags. The method has successfully been used to predict and size four flotation plants directly from bench-scale laboratory flotation testwork. All have since been commissioned, and have performed as predicted.The technique has now received broad acceptance within the South African mining industry, for example in the last year alone it has been used to drive flowsheet development for at least seven new plants. It is also being used to assist in the optimisation of existing operating plants.The methodology is described in this paper and verification of the methodology is presented using case studies of porphyry, polymetallic and PGM operations.INTRODUCTIONThere is considerable interest these days in the use of modelling to simulate flotation circuits, for process design and plant optimisation purposes. Although these models are proving to be useful tools for plant design and optimisation, their complexity can make them cumbersome – expensive to use and difficult for metallurgists to visualise and mentally absorb, without a background in each specific technique. In “SUPASIM” no attempt is made to measure flotation fundamentals, rather to use empirical relationships between laboratory flotation kinetics and plant performance – relationships that hold up well to validation exercises as will be demonstrated later in this paper. Although not designed to be as comprehensive as other models, “SUPASIM” is easily understood by the operating metallurgist and can be quickly and easily applied."

Jan 1, 2004

By Steve Cole

"The economic and strategic importance of PGE bearing deposits is fuelling renewed exploration and development efforts in the precious metals mining sector.This paper presents a review of the various techniques used in the processing of PGE bearing ores, from primary benificiation to processing routes for the different flowsheets that have been developed amongst current producers. Recent innovations such as preconcentration of ore using gravity separation, recent trends in flotation circuit design and the development of hydrometallurgical routes for the direct treatment of flotation concentrates without the need for smelting will be discussed. Data from recent projects will be presented to illustrate common characteristics of PGE ores and concentrates.INTRODUCTIONThe six platinum-group elements (PGE): ruthenium, rhodium, palladium, osmium, iridium and platinum, together with gold and silver, are considered to be ""precious"" metals. The recent spike in platinum and palladium prices coupled with the projected increase in demand for the metals has fuelled a spate of exploration and new projects in the PGE sector. Historically primary producers of PGE metals have controlled the flow of information relating to the mining and processing of these ores into the public domain. Very little published information relating to individual operations and processes is available in comparison to the abundant literature relating to other metals.The purpose of this paper is to provide a general overview of the issues relating to the processing of PGE ores. Each topic discussed could easily be the topic of a paper or book and so in many cases only the surface of the topic will be scratched. An attempt has therefore been made to provide as many references as possible.This paper discusses the classification and location of PGE ores, the mineralogical factors that affect recovery of PGE's, methods currently used for recovering PGE's and process trends in PGE metallurgy."

Jan 1, 2002

By Jocelyn Bouchard, Claude Bazin, Sami Makni, Rolando Quispe

"Finely disseminated minerals in ores require intensive size reduction to achieve sufficient liberation for the subsequent concentration process. The use of small grinding media in conventional ball mills as a replacement for the usual 2.5 to 3.8 cm balls (1.0 to 1.5 in) produces a finer size distribution at a lower power drawn by the mill motor. However, the conditions ensuring a successful application of using small media for fine grinding are still not fully understood and some plants faced issues to keep the newly introduced steel charge inside the mill during industrial trials. The retention conditions of small media are investigated in this paper using a continuously operated 40 x 40 cm laboratory grinding mill. The tests assess the effect of the steel charge level, the slurry solids concentration and the feed rate on the rate of ejection of the grinding media. The dominant variable is found to be the filling of the mill with the grinding media, followed by the mill feed rate. Results show that increasing the slurry solids concentration within a grinding mill may be favorable for the retention of the media inside the mill.IntroductionProcessing of complex ores often requires the use of fine grinding to liberate finely disseminated minerals. Grinding requirements for a P80 of less than 0.02 mm are not uncommon, and different grinding mills are available for such application (Leonida, 2014; Pease et al., 2006; Davey, 2006; Orford et al., 2006; Nesset et al., 2006). Even conventional horizontal ball mills charged with of 2.5 cm or larger grinding media can be used for fine grinding. However, simulation (Orford and al., 2006) and plant observations (Alves and L-Bouchet, 2005; Brisette, 2010; Brisette and Roman, 2012) demonstrated the advantages of using smaller grinding media in terms of size reduction and energy consumption."

Jan 1, 2015

By Ronald E. Hamilton

"An attempt to review the recent literature on comminution reveals at once that the subject has many ramifications and that the applications are so diverse that there are very few general statements which can be made.It. seems reasonable to start classification on the basis of size of material as Input to the comminution process. However, we find that this can only be done in a very imprecise manner.The initial step of breaking rock from its natural state of very large pieces in geological formations into sizes suitable for processing is accomplished by blasting. This step in the process has not been ex-amined in this project except to note that great changes have been made during the last decade or so in the explosives used, and in the method of handling them. We should determine what effect changes in mining methods can have on the need for crushing.The second step in the process is usually primary crushing, performed by gyratory or jaw crushers. The largest chunk which can be fed to a jaw crusher depends on the size of the machine, and should be larger than the largest fragment produced in the miring process. It is obvious that the larger the crusher, the less care required in mining to en¬sure the absence of rocks too large to be crushed. The optimum size of crusher to minimize overall cost of mining and reduction is not at all obvious, and no information on this point has come to light in this investigation.It is rather generally accepted that size reduction is most efficiently done in small stages, and that different machines have different opti¬mum size ranges of feed. For example, crushers are preferred for sizes above about 1"", rod mills for the range between 1"" and 0.1"", ball mills are preferred from 0.1""down to perhaps 10 microns, and vibratory mills, or jet mills, below 10 microns."

Jan 1, 1976

By R. W. Watson, H. D. Peer

"This paper outlines the history of steel linings in the Autogenous Mills, the factors influencing the decision to convert to rubber lining, and the operating and cost experience with the rubber liners to date. INTRODUCTIONSherman Mine is an open pit iron ore mining, concentrating and pelletizing operation located at Temagami, Ontario. The operation employs 392 hourly employees and 81 salaried employees and has an annual capacity of over one million L.T. of high quality iron ore pellets produced from low-grade magnetite ore.The Sherman Mine is a joint venture; 90% owned by Dominion Foundries and Steel Limited (Dofasco) of Hamilton, Ontario, and 10% owned by the Tetapaga Mining Company, a wholly-owned subsidiary of the Cleveland Cliffs Iron Company of Cleveland, Ohio. The operation and management of the mine is by Cliffs of Canada, Limited. Development of the property was started in 1965, with pellet plant production beginning on March 17, 1968. At the present time, the orebodies contain sufficient reserves to sustain operations at current production levels for 30 years. Mining was originally carried out in three orebodies, the North, South, and West pits. The North Pit has been exhausted and mining operations ceased in the spring of 1980. A fourth pit, the East Pit, will be developed during the early 1980's."

Jan 1, 1981

By T. Lux, M. Hanel, Degel, A. Filzwieser, R., H. Joubert

It is the increasing demand for an economic and cost saving operation mode that requires effective cooling in order to achieve low refractory wear and good furnace lifetime, which is making cooling technology an important aspect of furnace operation. In addition, the requirements for safety are getting more and more into focus. However, the use of water—today’s standard cooling medium—has major drawbacks as it can cause problems both during furnace start up and operation, namely hydration problems, corrosion, and explosion. Not to forget the severe risks for the operators as well as economical damage in case of a malfunctioning water cooling system. With this new and patented cooling technology ILTEC and the ionic liquid IL-B2001 as the cooling medium, it is possible to realise a water-free cooling solution and therefore the door is wide open to rethink existing and conventional cooling solutions. Furthermore, there is also the chance to recover heat from the process in a more efficient way. However, since the technology is novel and unique there are a lot of concerns and doubts regarding safety for plant operators and employees. The paper is intended to cover both: highlighting the enormous potential of the technology but also to eliminate concerns mainly caused by rumour and unawareness. INTRODUCTION All of us are aware of the risks when water is used as a coolant and placed in the vicinity of the liquid metal phase. Unsuitable design solutions or wrong operation modes of the furnaces or failures of refractories can cause a direct contact of water with liquid metal. The consequences can lead to equipment failures, vessel destruction but even worse to injuries and even fatalities. Over the past decades, countless incidences were reported. Fatal accidents caused by water coming into contact with liquid metal happen every year (Oterdoom, 2014; Filzwieser, Konetschnik, Filzwieser, Wallnerm & Preiss, 2014). With the novel ionic liquid cooling technology virtually all negative effects of a water cooled system regarding safety are eliminated and even additional benefits can be provided (Voermann, Ham, Merry, Veenstra, & Hutchinson, 1999;Verscheure, Kyllo, Filzwieser, Blanpain & Wollants 2006; Wallner, Filzwieser & Kleicker 2006). The fact that no explosion occurs when IL-B2001 gets in contact with molten metal results in a revolutionary solution for the metallurgical industry in terms of safety—new safety standards can be achieved.

Jan 1, 2019

By H. Warren Newcomen

The southwest wall of the Lornex Pit at the Highland Valley Copper mine has been experiencing slope displacements since 1978. Measures to manage the displacements on previous pushbacks have included stepping out, scheduling pushbacks to unload the crest of unstable areas, slope dewatering and mining with intensive slope monitoring. The final pushback on this wall is currently being mined and substantial modifications to the slope geometry could prove to be uneconomic. As a result, a campaign of surface water collection and diversion, horizontal drainhole drilling and deep well drilling is currently underway to maintain an acceptable degree of stability to the end of mine life. The various factors contributing to instability, including engineering geologic controls, rock mass strength, and surface and groundwater hydrology are presented. Movement trends, displacement magnitudes and stability analyses results are also discussed.

May 1, 2002

By C. J. Van Treeck

PGE concentrations of 18 g/t occur in the pyroxene rich rocks at the Union Bay Alaskantype complex. This PGE enrichment is hosted in magnetite veins. These veins cross magmatic layering and have an irregular morphology in both outcrop and thin section. Fe-Ti oxide geothermometry suggests that this mineralization took place between ~700-400°C. A variation in the amount of ilmenite and Mg- Al spinel exsolution in magnetite correlates with temperature estimates, lower temperature magnetite has less exsolution. Hydrous silicates form an alteration envelope around magnetite veins with a formation temperature of <575oC, vary with temperature, and contain appreciable amounts of Cl. Interaction of a PGE-Fe-Cl rich fluid with clinopyroxene increased the fluids pH and decreased PGE and Fe solubility depositing a PGE enriched magnetite within the Pyroxenites and Olivine Pyroxenites of the Union Bay complex.

May 1, 2003

By Don Thompson

It isn?t a lie if you don?t tell the whole truth The pictures National Geographic didn?t print Other photos National Geographic didn?t print?

May 1, 2009