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ABSTRACT Understanding process histories and worker exposures in nickel production operations is critical in determining the role nickel compounds play in respiratory cancer incidence. As part of a series on Vale Canada’s (previously known as Inco) nickel processing operations, this paper includes descriptions of Ni electrolytic operations at refineries in Port Colborne, Ontario (1922–1984), and Thompson, Manitoba (1961–present). Industrial hygiene measurements, by area and personal sampling, of workplace aerosols at these operations are reported.

Jan 1, 2014

By Robb. V. M., F. Walraven, L. J. Robb

"Abstract -The old Albert Silver Mine is a polymetallic deposit comprising concentrations of Cu­ Pb-Zn-Ag-U-F within a set of sub-parallel quartz-hematite veins which occur within the fine-grained apical phase of the 2050 Ma old A-type Bushveld granites. Mineralization occurs as an early pyrite­ chalcopyrite-arsenopyrite-galena-sphalerite-(argentiferous) tetrahedrite paragenesis followed by a later, more oxidized assemblage comprising chlorite-hematite-fluorite-pitchblende. Accumulation of metals appears to have taken place at the interface between a coarse-grained porphyritic granite and an overlying fine-grained phase: veins occur in the latter and represent leakage of magmatic fluids from the differentiated, water-saturated, subjacent granite.Mineralization processes in the Bushveld granites are believed to be related to long-lived circulation of dominantly magmatic fluids stimulated by the high heat productive capacity of the host rocks. Endo- and exogranitic tin-tungsten and base metal mineralization formed during an evolving hydrothermal system that lasted for several hundred million years, forming innumerable small- to medium­ scale polymetallic deposits. At the Albert Silver Mine, unroofing of the cover sequences at circa 1600 Mato 1700 Ma resulted in the incursion of lower-temperature, high-f02 meteoric fluids which remobilized the earlier sulfides and introduced the paragenetically late U-F mineralization ."

Jan 1, 1994

By K. Nasrallah

"The Dumont deposit is a large (1,179 Mt proven and 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 project from a scoping study in 2010 through to completing the feasibility study in July 2013.The Dumont deposit in a nickel deposit with the recoverable nickel contained in three minerals; pentlandite, haezlewoodite and awaruite. The minerals are recovered by a combination of flotation and magnetic separation. Over the course of the studies many flowsheet design decisions and changes were made. This paper outlines an overview of the project, flowsheet design including the comminution circuit, desliming and awaruite recovery. The overall resulting flowsheet that was used for the feasibility study is then presented along with the confirmatory locked cycle testing that showed the feasibility design basis was able to produce the predicted concentrate grade and recovery.IntroductionRoyal Nickel Corporation (RNC) is a mineral resource company headquartered in Toronto, Canada, primarily focused on the exploration, evaluation, development and acquisition of base metal and platinum group metal properties. RNC's principal asset is the Dumont Nickel project (Dumont project) located in the established Abitibi mining camp, 25 km northwest of Amos, Quebec. RNC acquired a 100% interest in the Dumont property in 2007. The mineral claims covering the Dumont deposit are currently held 98% by RNC and 2% by Ressources Québec.The Dumont project is located in the province of Quebec in the municipalities of Launay and Trécesson approximately 25 km by road northwest of the city of Amos, 60 km northeast of the industrial and mining city of Rouyn-Noranda and 70 km northwest of the city of Val d’Or."

Jan 1, 2016

"Each and every flotation plant must produce daily/weekly/monthly production reports in which metal balances for payable and penalising elements are presented. Several factors including ore heterogeneity and harsh production environment affect the reproducibility of the reported data. Best practices of metal accounting thus prescribe that production reports be accompanied by measurement quality reports quantifying the reproducibility (a data quality metric often expressed as a relative standard deviation) of each data reported. Ignoring the irreproducibility of measurements may lead to the perception that random errors have been totally eliminated through statistical data reconciliation, which is wrong. This paper aims at explaining the full lifecycle management of reproducibility estimation from the outset at the measurement process to its reporting after having been through the statistical data reconciliation process. Indeed, the reproducibility of reported data can be obtained by performing a sensitivity analysis. Necessary conditions for obtaining a truly representative assessment of measurement reproducibility are stated. Typical levels of measurement reproducibility found in operating flotation plants are also reported. These numbers can be used as benchmarks for reproducibility levels that can be realistically expected.IntroductionEach and every flotation plant must produce daily/weekly/monthly production reports in which metal balances for payable and penalising elements are presented. Such production reports are the most expected output from a metal accounting system (MAS). The duly recurrence of this task combined with an insufficient level of automation has somehow contributed to the misleading perception that it is mainly a clerical work. However, as shown in Figure 1, a MAS encompasses way more than just a reporting system. Acknowledging that the content of production reports indubitably origin from raw measurements has important implications for how both the reports and MAS should be monitored."

Jan 1, 2016

By Walter Valery, Peter Radziszewski

"The NewCrest Cadia operation boasts the largest SAG mill commissioned last June 1998. A request was made to shed some more light on possible SAG mill charge behaviour. Three different software were used to simulate SAG mill charge behaviour:Mishra/Rajamanis MillSoft DEM charge motion program, Radziszewskis agglomerated DEM charge motion program and Powell/Nuricks MillTraj outer trajectories program. The contexts simulated are: 20/30 % charge volume, 65/75/85 % critical speed using the Hi-Lo lifter configuration specified for the mill as well as a Hi-Lo 60 degre lifter face configuration. Further, lifter interval was also studied to determine the effect on power draft. Power predictions are compared with those obtained during the commissioning period.INTRODUCTIONThe NewCrest Cadia operation is located outside of Orange, New South Wales, Australia. With proven reserves of 190 million tonnes at a grade of 0.75 g/t Au, the mill was designed to process 17 Mtpa (2065 tph) of ore with an 86% copper and 73% gold recovery. The grinding circuit (Fig. 1, Table I) boasts the largest SAG mill (Fig. 2) and was commissioned last June 1998."

Jan 1, 1999

By A. P. Craig

"I HAVE BEEN looking forward to addressing this particular audience about Trans-Canada Pipe Lines because you men, more than most, understand the problems of the pioneer. Trans-Canada Pipe Lines qualifies as a pioneer on two counts: it is certainly pioneering a completely new industry in Canada -the long-distance transmission of natural gas -and it has at least a few of the problems that are expected and normal to any pioneering venture.This morning, I’m going to try to give you a sketchy picture of our project and a brief report on its current status and our progress to date; and then a broad picture of Canadian markets for natural gas.The physical characteristics of the Trans-Canada Pipe Lines project have been discussed so often that I am not going to take the time today to quote a lot of statistics on pipe sizes, miles, tons of steel, etc. Suffice it to say that this project, estimated to cost approximately $350,000,000, will be the longest large-diameter gas pipe-line ever built anywhere.Let me try to paint a broad picture of this great national project, using only a few basic 'round' figures.First, it involves exploration for and development of the natural gas fields in Alberta and other provinces -the cost of which will run into hundreds of millions of dollars.Then comes the gathering, stripping, and cleaning of the gas before it can be delivered to Trans-Canada. This will cost close to $100 million.Next we have the Trans-Canada Pipe Lines project for transmission of the gas to Eastern markets -estimated to cost $350,000,000 during the first three to four years and making natural gas economically available to one-half the population of Canada."

Jan 1, 1955

By Gus Van Weert, Peter Kondos

"Ore sorting has been quite successful in providing a separation means in the rock size range of 1 to 6 inches; a range where mineral dressers do not have many options. The industrial minerals and recycling worlds have embraced this technology. However, ore sorting has not found wide application in the base or precious metals mining industry. One reason for this is thought to be the reliance of most sensors on rock surface characteristics, not very useful in case of sulphides, non-existing in case of gold. Microwave heating, however, is specific for sulphides and graphite (or carbonaceous matter) embedded in the rocks; washing or even drying does not appear necessary. Separation can be done afterwards by already existing ore sorting technology using infrared sensors. Test results on six Nevada gold ore samples are presented in detail. Some simple test procedures are also presented for those wishing to explore the microwave potential of sulphide sorting in their own operations.INTRODUCTIONMineral processing in the base metals industry most often involves upgrading of the ore, concentrating the valuable mineral fraction by classic methods, such as flotation. Since the liberation of minerals in the ore occurs mostly at or below the 100 micron level, the industry has been living with fault lines, so to speak, between blast hole spacing (10,000 mm), run-of-mine ore size (100 mm) and beneficiation size (0.1 – 0.01 mm). The acceptance of ore sorting will inevitably lead to the revisiting of the following questions: “Exactly how much below ore grade rock ends up in the mill because the geologists or the miners cannot define the resource boundaries more precisely? How can the economics of dilution be improved? How many ore grade rocks are lost with the overburden?”"

Jan 1, 2007

By Patrick R. Stephenson

The current version of the JORC Code was issued in 2004 and since that date the Australian Securities Exchange, in collaboration with JORC, has issued a number of companies? updates to provide guidance on various reporting issues. An interim review will be undertaken during 2010 to meld these updates with the current 2004 Code. This will be followed by a full review during 2010/11 covering all aspects of the Code and focusing particular attention on: ? clauses / guidelines relating to Exploration Results1, exploration targets and the reporting of historical estimates; ? issues relating to the Public Report2, including definition, the requirements for Competent Person sign-off, level of disclosure and mandatory requirements; ? guidance on techniques to quantify resource / reserve estimation uncertainty; ? the level of study required to convert Mineral Resources to Ore Reserves, and disclosure of prices and economic factors; ? expansion of the requirements for reporting of marketable material for bulk commodities; ? the use of language and tone that anticipates new and emerging technologies and techniques for the qualitative and quantitative measurements of data; and ? linkages to valuation and the valuation code (The VALMIN Code). Although the Canadian and Australian reporting regimes for public statements on Exploration Results, Mineral Resources and Mineral (Ore) Reserves are similar in intent and coverage, they differ in detail, sometimes substantially. Canadian requirements are generally more wide-ranging and prescriptive than Australian requirements, including in the need in many situations to publicly lodge a Technical Report, a requirement that does not exist in Australia. Australian-listed companies seeking to list in Canada, and Competent Persons seeking to act as Qualified Persons in Canada, need to ensure that they are fully conversant with Canadian regulations and how they differ from those in Australia.

May 1, 2010

By O. J. C. Runnalls

"Canada became the world's largest uranium producer in 1984. That leadership position is likely to be maintained for many years into the future because of a firm production base, many undeveloped known deposits with commercial promise, and a large geologicalpotential for new discoveries.There are some uncertainties on the horizon, principally because of restrictive actions in process within the U.S.A., which are aimed at preserving a deteriorating domestic uranium industry. Should such actions result in import restrictions, for example, there would be a negative effect on foreign producers at least in the short term. Canada may avoid such difficulties under a tentative U.S.-Canada free-trade agreement where restrictions on the import of Canadian uranium into the United States would be eliminated. Over the longer term, demand for Canada's uranium resources will grow because of the foreseen growth in the world's installed nuclear power capacity. IntroductionSince the phenomenon of nuclear fission was discovered in 1938, the utilization of uranium has grown substantially. Initially, the principal use for uranium was in the production of nuclear weapons. However, once civilian nuclear power reactors began to be built in the 1950s, an increasing fraction of uranium output was directed to the production of fuel elements for use in electricity generating stations.The cumulative uranium production by those countries in the World Outside Centrally-Planned-Economies Areas, WOCA, during the period 1938 to 1985 exceeded 800 000 tonnes of uranium. Some 60% of that was mined in the United States and Canada, as indicated in Figure 1. In 1986, nearly 80% of WOCA output came from five countries, Canada, United States, South Africa, Australia, and Namibia, as indicated in Table 1 and illustrated in Figure 2.During the past decade the world annual consumption of nuclear energy has more than tripled (Fig. 3). As of December 31, 1986, the world total of nuclear power reactors had reached 394 with a total net capacity of 270 GWe. The thermal output from nuclear power plants in 1985 exceeded 60% of the energy contained in all of the oil produced that year in the Middle East. Thus, nuclear power has already become an important component in the world energy supply picture."

Jan 1, 1988

By E. Amini

"While methods exist to allow the simulation and optimization of existing flotation operations, there is a deficit in the ability to predict the performance of a new ore type pre-processing. A laboratory scale batch flotation testing methodology has been developed to assess the flotation potential of ores (known as the JK Floatability Index or JKFI). Previous work conducted by Alexander and Collins (2008) showed that the test could be used to predict full scale results in base metal ores. In this work, JKFI tests were applied to three different types of ore and one blend from a greenfields gold deposit to show the test applicability to flotation of precious metals. The results from the JKFI test on one ore type were then used to predict the response of all ore types (including the blend). To validate the predicted kinetic parameters, a comprehensive survey was performed on a pilot plant where each of ore types was processed in the circuit. An acceptable agreement was found between the experimental recoveries and predicted recoveries which indicate the potential of this method for use in predicting the flotation response of an ore.INTRODUCTIONOver 100 years, flotation has been considered an efficient method to concentrate different types of sulphide and oxide minerals and coal. Thus, numerous research studies have been undertaken to find an appropriate model to predict the behaviour of particles in flotation circuits (Barnwal et. al., 2006; Bascur and Herbst, 1983; Cecile and Villeneuve, 1991; Deng et. al., 1996; Zheng et. al., 2006). Most methods are based on the ore flotation response in an industrial plant which is expensive and time consuming to characterise. It is difficult to reliably predict flotation response for new types of ores in industrial scale plants.The floatability component modelling (FCM) approach, developed within the Australian Minerals Industry Research Association (AMIRA) P9 project, has been used to derive models of operating flotation plants for the purpose of simulation and optimisation (Alexander and Morrison, 1998; Alexander et. al., 2000; Varadi, 2006). This approach has been applied at a large number of operating sites treating a wide variety of ores. The approach requires metallurgical surveys to be undertaken in conjunction with batch flotation tests and cell characterisation. This allows ore and machine parameters to be derived, which are then used in the P9 Flotation Model. The development of a FCM generally requires a large commitment of resources and time. While there has been significant support of this approach in industry, the FCM approach is limited to ores already being processed (Runge, 2004; Wightman, 2006)."

Jan 1, 2009

By W. W. Culver

The paper explores the substance, circumstances and significance of the Whelpley and Storer Copper Process. The 1866 Whelpley and Storer patent specified a process combining mechanical and chemical engineering. The process called for a down-drafting shaft furnace with a horizontal flue connected at the bottom of the shaft. Powdered sulphide ore was roasted in the shaft and then sent forward fully oxidized to a bath of sulphuric acid and/or calcium chloride. The “water furnace” was developed in Boston, at a time when the city was home to most Michigan copper mining companies. The process was field-tested at Quebec’s Harvey Hill copper mine. In 1865 James Douglas, Jr. took over management of the Harvey Hill mine with the challenge of saving the family investment. He needed a way to make money from low-grade sulphides. Through his relationship with chemist T. Sterry Hunt, Douglas learned of a possible way ahead using the process developed by Whelpley and Storer. The paper confirms the centrality of publications, meetings, and networking in the advancement of metallurgy. The process is of interest historically, as much as anything, because it is one of the pillars of James Douglas’ distinguished career in copper. INTRODUCTION At the 1866 meeting of the American Association for the Advancement of Science (AAAS) in Buffalo, New York, T. Sterry Hunt (1826–1892) read a paper “On the Metallurgical System of Messrs. Whelpley and Storer.” The paper is part of a chain of events that constitute the foundation of James Douglas’ (1837–1918) success in the copper mining industry. To understand the career of Douglas over the early years of modern copper mining, we must necessarily start with Whelpley and Storer. Going back to Hunt’s paper, he concluded his remarks by asserting that the Whelpley and Storer Process was “capable of such wide and varied application, that it is probably destined to have a very important influence on the industry of the world” (Hunt, 1867a). He reached this conclusion reasoning that the process had overcome a critical metallurgical hurdle (Hunt, 1867a). Hunt, a geo-chemist in modern terms, recalled that the chemist of those years easily separated copper from “sulphuretted” ores by converting it to a soluble salt from which pure metal was precipitated by “an equivalent of iron.” The problem was to “…apply this principle in the working of copper ores on a great scale...” (Hunt, 1867a). Hunt noted that this very problem had “…engaged the attention of many metallurgists, and has given rise to various processes for obtaining copper by the moist way, many of which are nearly or quite perfect in their operation, but are lacking in practicability and cheapness” (Hunt, 1867a). Hunt thought Whelpley and Storer had overcome the low-grade sulphide hurdle with a commercially viable engineering breakthrough. Yet in the history of copper metallurgy, the process is missing. What happened?

Jan 1, 2019

The uphole bench extraction strategy at EKJV Management Pty Ltd?s Raleigh Mine, requires simultaneous horizontal and vertical exposure of paste filled stopes. In order to prevent excessive ore dilution, the paste fill must be of sufficient strength to prevent failure during exposure. A numerical modelling methodology has been developed to accurately simulate the initial stress distribution within paste filled stopes, together with the strain-softening loading response of paste fill material. Due to the narrow orebody width and high deformation behaviour of the host rock mass, high closure strains are likely to cause a stiff, brittle fill material to undergo crushing failure upon exposure. The stability of paste fill exposures at the Raleigh Mine was determined by conducting a series of three-dimensional numerical models that incorporate the extraction, filling and exposure sequence of paste filled stopes. Stability charts for 2.5 m and 3.5 m wide simultaneous horizontal and vertical exposures have been derived based upon the numerical modelling results. Implementation of the stability charts has proved successful in limiting the amount of ore dilution from paste fill and provides a basis to optimize paste fill cementation and stability throughout the life of the mine.

May 1, 2007

By G. H. Gale, M. A. F. Fedikow, L. B. Dabek

Rare earth element (REE) data are reported for ores, sul?de-bearing rocks and host rocks from massive sul?de deposits and barren sul?de facies iron formations in Proterozoic volcanic rocks of the Flin Flon-Snow Lake area, Manitoba. Some of the rare earth elements (e.g., Eu), are selectively leached in zones of intense alteration and redeposited together with the sul?des and silicatesin the uppermost parts of the alteration zones and at the rock-water interface. Chondrite normalized REE pro?les of layered sul?de ores and exhalites proximal to the deposits typically have positive europium anomalies and are enriched in light REE. In contrast, barren sul?de facies iron formations exhibit negative or ‘normal’ Eu pro?les. REE data are useful to explorationists in determining the presence of ‘off-hole’ metal-bearing sul?de zones, in distinguishing metal-poor sul?dic layers related to ‘economic’ hydrothermal activity from barren sul?de facies iron formation and in some instances as a means of establishing ‘ore-equivalent’ strata.

Jan 1, 1997

By G. H. Gale, M. A. F. Fedikow, L. B. Dabek

Abstract-Rare earth element (REE) data are reported for ores, sulfide-bearing rocks and host rocks from massive sulfide deposits and barren sulfide facies iron formations in Proterozoic volcanic rocks of the Flin Flon-Snow Lake area, Manitoba. Some of the rare earth elements (e.g., Eu), are selectively leached in zones of intense alteration and redeposited together with the sulfides and silicates in the uppermost parts of the alteration zones and at the rock-water interface. Chondrite normalized REE profiles of layered sulfide ores and exhalites proximal to the deposits typically have positive europium anomalies and are enriched in light REE. In contrast, barren sulfide facies iron formations exhibit negative or ‘normal’ Eu profiles. REE data are useful to explorationists in determining the presence of ‘off-hole’ metal-bearing sulfide zones, in distinguishing metal-poor sulfidic layers related to ‘economic’ hydrothermal activity from barren sulfide facies iron formation and in some instances as a means of establishing ‘ore-equivalent’ strata.

Jan 1, 1997

By Michael Stuart Parsons

The haulage cycle is the sequence which a haulage vehicle must first arrive at the loading area, then turn around and reverse into position. Once it is loaded, the vehicle leaves and travels to the unloading area, where again it must turn around and back up to unload. The cycle is repeated over and over again. The Vector Neutral truck is a rubbertired, self-propelled hauling vehicle designed such that it eliminates the requirement to turn around and back-up to either load or unload. Vector Neutral Truck Cycle: 1.) Travel from the load station to the dump station. 2.) Stop and dump load. 3.) Travel from the dump station to the load station. 4.) Stop and load. The Advantage is in the Difference: 1.) Shorter distance traveled. 2.) Fewer brake and steering actuations. 3.) Easier to automate. 4.) Easier to adapt for remote control operation.

May 1, 2003

By Jose R. Hernandez-Aguilar

"Three models to predict the effect of bubble size (Db) on metallurgical response were tested in a pilot-scale flotation column at Teck Highland Valley Copper mine. The column was fed with slurry collected from the Cu/Mo separation circuit. The first model was the one developed by Gorain et al. (1997), which assumes that the collection zone rate constant (kc) is inversely proportional to Db. The second model was the one proposed by Hernandez-Aguilar et al. (2010), which considers kc as an inverse square function of Db. The third model was the one developed by Yoon and Luttrell (1989) which provides expressions to describe the efficiency of particle collection (E) based on first principles. The results showed a significant bias between experimental and predicted data using the model of Gorain et al. (1997), possibly reflecting the model’s inability to explain the impact of bubble size, bubble rise velocity and flow regime on E. The model of Hernandez-Aguilar et al. (2010) well described the experimental evidence. The model of Yoon and Luttrell gave accurate and unbiased predictions. However, Yoon and Luttrell’s approach calls for a criterion to determine whether the flow regime is potential or intermediate, a subject that requires more fundamental research.INTRODUCTIONParticle collection, i.e., bubble-particle collision followed by attachment, is the basis of flotation. In a quiescent environment (such as the one observed in a column, or away from the impeller in a mechanical cell), a collision event can take place as long as the “degree of turbulence” caused by the rising bubble does not prevent particle and bubble to flow in close proximity. Upon collision, the particle slides on the bubble surface for a period of time. If the particle is hydrophobic, attachment occurs when the “sliding time” is longer than the “induction time”, which is the time required to thin and rupture the intervening liquid (usually water) film forming a three-phase contact angle. While the induction time is largely influenced by the degree of hydrophobicity of the particle, the degree of turbulence is governed by the bubble size. Generally, direct control of bubble size is not exercised by most mineral processing practitioners, in spite of its obvious importance. Studies to model the effect of bubble size on particle collection using fundamental approaches have been conducted (e.g., Anfruns and Kitchener, 1977; Webber and Paddock, 1983; Yoon and Luttrell, 1989; Dai et al., 1999). However, these models have been validated under highly idealized laboratory conditions (micro-scale experiments using single minerals and uni-sized bubbles), far from resembling those existing in practical industrial applications. Fundamental studies to interpret the effect of bubble size on particle collection in industrial environments are largely absent in the literature. Partly because of this lack of practical knowledge, many mineral processing practitioners perceive laboratory “bubble size” studies to be valuable academic exercises, but not something that can be directly applied to daily production issues."

Jan 1, 2011

By J. A. Finch

Individual mineral cyclone performance curves were determined for the four major minerals at two lead-zinc concentrators. Sizing was by screen and cyclosizer down to approximately 10 um, with lead , zinc and iron as saying of each size fraction. The performance curves were similar in shape and located according to the mineral specific gravity, Pm. The curves displayed a discontinuity at the fine end and a magnitude of short-circuiting of fines to the underflow which increased with Pm. Mass fraction of water to the underflow was only a guide to this short-circuiting. Sharpness of separation seemed in dependent of Pm. An inflection in the over-all performance curve was shown to be a consequence of the individual component mineral performance. A general relationship was observed showing that the flow regime of classification changed from laminar/ intermediate to turbulent with increasing cyclone feed size. Individual mineral size reduction for the four major minerals at one of the concentrators was also determined. Size reduction of the silica was greater than that of the galena, in contradiction to their accepted relative grind-ability. The observation did correlate with silica being much coarser than the galena in the feed to the ball mill. It is suggested that the silica acted as a buffer to the galena.

Jan 1, 1977

By Guy Chevalier

The QCM Mount-Wright mine and concentrator complex produces about 14 M tonnes of iron concentrate annually. Approximately 9.5 M tonnes of this concentrate are used to produce iron ore pellets at four different silica grades: Three for blast furnace operations and one for direct reduction furnaces. The paper presents the scientific approach that led to the realization of two projects where the acquisition of new process equipment led to an improved pellet plant iron recovery, a better flexibility and to lower operating costs as well as to the production of fine iron ore concentrate from the Port-Cartier tailings pond. Typical 4.8 % SiO2 concentrate is processed to achieve required pellet silica content. This is obtained with the aid of hindered settlers or hydraulic classifiers, screens, whims and, lately, spirals. The increasing demand for low silica iron ore products resulted in a greater need for upgrading. The Pellet Plant upgrading capacity being limited, more and more iron units were lost. Base on test works results and economic evaluations, QCM engineers figured out a way to increase efficiently their upgrading plant capacity and go back in the pond gather what has been lost in recent years of operation.

May 1, 2007

By Eugene (Gene) Bounds

The Mining industry faces many challenges, one of which is the demand to communicate over a variety of media, be it visual, sound, voice, data or any combination. Over the years multiple infrastructures have been put in place to overcome environmental obstacles and address these communication needs. A mine is an aggressive environment for electronic equipment and as such only the best quality equipment can perform under those special conditions of e.g. temperature, dust and humidity. Siemens Canada and its partner LComm will discuss a mining solution using a unique combination of technologies based on fibre optics, standard communication interfaces, passive antenna infrastructure and wireless services. The presentation looks at maximizing the use of infrastructure, reducing costs, addressing difficulty of communications coverage above and below the surface and the capability to future proof the capital investment as new requirements and applications are identified. Discussion will address: Wireless voice, high speed data Data acquisition for process control from sensors Video for remote control and security Miner safety and location Timely receipt of large volumes of information

Apr 1, 2005

By Thomas Deschamps

The main objective of this work was to investigate the effect of binder addition on the geochemical properties of surface paste tailings. Nine leaching columns were prepared following different disposal configurations: non-cemented, non-cemented with cemented layers, and cemented .The proportions of cement by total paste weight were between 0 and 1% for a whole column; the maximum amount of cement in a single layer was 2%. The material used was a sulphide-rich tailings coming from a Canadian hard rock polymetallic mine. The columns have been flushed once a week during 30 weeks. The recovered leachates were analyzed for pH, Eh, conductivity, and a wide range of elements. The drainage rates were monitored during the initial disposal as well as after each column flush. The results show that binder addition can improve the whole environmental performances for some of the studied disposal configurations. The disposal configuration consisting of intercalation of three 2% cement paste layers within non-cemented layers (0.66 wt.% of cement for the whole column), and the configuration with 2% cement added only in the two bottom layers (0,44 wt.% of cement for the whole column), showed the best results in terms of water quality and drainage rates.

May 1, 2007