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By A. LA. Salama, D. B. Hyma

"The Western Research Centre (WRC) of CANMET located in Devon, Alberta, is a modern research facility offering services ranging from fundamental research to pilot plant investigations. Recently, a 0. 76 metre diameter by 7.9 metre high Flotaire column flotation cell was installed as a demonstration unit for Canadian coal producers. Because the column cell is intended to be used for research, development and demonstration, WRC recognized that additional sensing equipment and improved process control would be required to generate good data for subsequent column scale-up and engineering design.A low cost, personal computer based control system was, therefore, designed and installed. This paper describes the stepwise procedure in developing the control strategies, selection of system software and hardware, and installation and configuration of the system.Preliminary performance data on a western Canadian coal sample are also presented. Future testwork is planned on additional coal samples to expand upon existing database."

Jan 1, 1993

By J. Baz-Dresch

"The most cost-effective method of placement of the high strength fill used in the Cannon Mine' s overhand cut-and-f ill bench stopes was determined to be truck haulage. Constraint s imposed by the mine layout dictated the use of a truck which could dump its load in a fifteen-foot high drift. The Dux Teledumper truck was selected as the most suitable unit for this application based upon operational and maintenance parameters which included a telescoping, tilting dump box; large load capacity; and robust construction. Development of the truck continues through the cooperation between the manufacturer and user. INTRODUCTIONThe Cannon Mine is situated in the centre of Washington state, approximately midway between the cities of Spokane on the east and Seattle on the west. The mine complex is located three block s south of the Wenatchee city limits at the eastern base of the Cascade Mountain range.Asam era Minerals (U.S.) Inc., with 5I% ownership, operates the Cannon Mine. Breakwater Resources, Ltd. holds the remaining 49%.Annual paroduction is 520 000 tons per year, presently on a 21-shift per week operating schedule for both the mine and the mill.All production is presently won by overhand bench stoping with backfill. Stoping starts with 15-ft high by 24- or 30-ft wide sill cuts driven above and below a stope block . A drop rai se and slot are used to open a bench which is then slabbed toward the open slot. Truck-placed backfill is dumped into the mined - out stope from the upper sill cut. This stoping sequence is repeated until the top of the ore block is reached . The top sill cut is then tightly filled with backfill to minimize subsidence and to provide adequate roof support during extraction of the pillars.Mining equipment consists of hydraulic drills and rubber-tired, diesel scoops and trucks."

Jan 1, 1989

By P. A. Studemeister

"A trondhjemite stock intrudes a volcanic sequence that has massive sulphide lenses and that is metamorphosed to the greenschist facies at Gutcher Lake, 25 km north of Wawa, Ontario. The stock is 4 km2 in plan and is partly enveloped by an aureole of chlorite-epidote-amphibolehornfels up to 1 km wide. Within this contact aureole, biotite is partly pseudomorphosed by chlorite;epidote and hornblende are mottled by chlorite, calcite, plus quartz; albite has 0% An to 8% An; and hornblende porphyroblasts have actinolite rims. The stock has chlorite pseudomorphous after biotite; and feldspar is mottled by white mica plus calcite and has a clear rim of albite. Fractures filled with quartz, calcite, ankerite, chlorite, white mica, pyrite, and native gold cross-cut the stock and its hornfels aureole. These gold-bearing veins are enveloped by foliated rocks with quartz, calcite, white mica, and chlorite that grade outward from the veins into trondhjemite or hornfels.The stock, emplaced into a submarine volcanic series, emanated heat that caused seawater to convect and formed a contact aureole of hornblende hornfels. The stock eventually intruded its aureole and this culminated with regional metamorphism to the greenschist facies. Regional metamorphism hydrated the stock and its hornfels aureole. Native gold precipitated with quartz along fractures from metamorphic flu ids in response to cooling and wallrock hydration. exploration for this type of gold deposits should focus around felsic intrusions that have albite and that have contact aureoles retrograded by regional metamorphism."

Jan 1, 1985

By R. M. Clowes

"As part of LITHOPROBE's multidisciplinary earth science research program to understand the evolution of the North American continent, studies have been undertaken in a number of key areas in Canada. In the Trans-Hudson Orogen of Manitoba and Saskatchewan, LITHOPROBE results require re-evaluation of tectonic models related to its origin. In the Abitibi greenstone belt of Quebec and Ontario, results indicate a more complex evolution for the southern Superior province, one that links with the development of gold and massive sulphide deposits. As part of the program, the seismic reflection profiling method is being adapted for the mining industry. Three examples demonstrate the subsurface information that can be obtained. In Noranda, the base of the volcanic Blake River group is imaged and reflectivity is tied to geology through well logs; in Matagami, the zone of mineralization is shown to be downdropped along a majorfault; in Sudbury, a new structural model is developed, one that shows marked asymmetry at depth and indicates that some ore-bearing units on the margins of the igneous complex may be repeated at depth. IntroductionLITHOPROBE is Canada's national, collaborative earth science research project, established to develop a comprehensive understanding of how the North American continent has evolved. Ten transects, or study areas, were chosen to investigate pivotal geological features to their deep lithospheric roots. They span the country from the Pacific to the Atlantic Oceans and from the U.S. border to the Yukon and Northwest Territories, and geological time from four billion years ago to the present. A multidisciplinary approach, which is spearheaded by seismic reflection techniques, is essential to developing complete interpretations and outstanding scientific results. LITHOPROBE also has pioneered the use and demonstrated the value of using reflection technology to determine subsurface geology in mining camps.This paper provides an overview of the transects and their significance for the tectonic evolution of North America. Two specific examples demonstrate how we detennine present three-dimensional lithospheric structure and past geotectonic processes which formed it. The application of the reflection method to imaging complex structures in ""shallow"" crystalline rocks has been developed with funding and other support from the mining industry and provincial geological surveys. Sustaining funds, however, are derived from the Natural Sciences and Engineering Research Council and Geological Survey of Canada. Emphasis has been placed on developing deeper penetrating tools for exploration of deeply buried, but economically retrievable, mineral resources near existing mines, where an expensive infrastructure already is in place. Three examples, Rouyn-Noranda in western Quebec, Matagami in northwestern Quebec and Sudbury in northeastern Ontario, illustrate these developments."

Jan 1, 1994

By G. R. Sadowski

"Large subhorizontal joints have been found in the foundation excavations in basalt and granite of Brazilian Dams. Some spread for hundreds of square meters showed slickensides—polished surfaces plus striations—and laminations interpreted as related to shear displacement, what substantially reduced their shear strength and imposed special reinforcement measures against the potential sliding of overlying concrete structures. The geological characteristics of these discontinuities have raised speculations related to their origin, be it related to mechanisms of bulging, cambering or to some tectonic or primary geological event.Several geologists and engineers from the northern hemisphere including Terzaghi already showed to be concerned with their role in granite foundations while in the southern regions Brazilian authors have found similar occurrences but also affecting individual lava flows of continental flood basalts in the foundations of major dams of the Parana Basin, which they designated under the particular name of “fault-joints”. This double-standard designation is self-explanatory of the difficulties involving their origin and related geomechanical properties: faults or just shear joints?Recently, similar features were encountered in the foundations of large dam constructions in anorogenic granites inserted in the realm of the Brazilian Amazon, where some of these discontinuities exhibit features common to tectonic thrusting combined with deep tropical weathering.The evidence of preshearing along the surfaces of such fractures, also associated to products of deep weathering, reduces their geomechanical strength substantially, suggesting values of ultimate phi spanning 12 to 28°. The detection of these descontinuities during initial investigation phases continues to be a major complex task in geological risk evaluations surveys. Trenching associated to some geophysical exploration techniques, although considered to be very basic exploration techniques are still the suggested methods for their forecast and previous determination."

Jan 1, 2015

By Shahram Tafazoli

This article presents a novel technology for sensing the size of rocks after blasting in hard rock mines. Blast engineers require rock size statistics to carefully adjust the blasting parameters. The rock fragmentation requirements vary depending on the ore type and crusher specifications. The most popular statistical parameters in the industry are the so-called P numbers (e.g., P80 and P100). A machine vision based system is introduced here for automatic image collection and fragmentation analysis of the material right inside the bucket or dipper of mining shovels. A heavy-duty camera provides the required imaging data to an embedded computer mounted inside the cab. A custom machine vision software continuously analyzes the captured bucket images and stores the suitable ones in local storage which are then fed to a Desktop software for automatic fragmentation analysis. This technology has been developed by Motion Metrics International and is commercially available as FragMetrics?.

Oct 1, 2009

By Shahram Tafazoli

This article presents a novel technology for sensing the size of rocks after blasting in hard rock mines. Blast engineers require rock size statistics to carefully adjust the blasting parameters. The rock fragmentation requirements vary depending on the ore type and crusher specifications. The most popular statistical parameters in the industry are the so-called P numbers (e.g., P80 and P100). A machine vision based system is introduced here for automatic image collection and fragmentation analysis of the material right inside the bucket or dipper of mining shovels. A heavy-duty camera provides the required imaging data to an embedded computer mounted inside the cab. A custom machine vision software continuously analyzes the captured bucket images and stores the suitable ones in local storage which are then fed to a Desktop software for automatic fragmentation analysis. This technology has been developed by Motion Metrics International and is commercially available as FragMetrics?.

Oct 1, 2009

By Raja V. Ramani, Sukumar Bandopadhyay

"The dispersion of diesel contaminants into the mine atmosphere is a variant of general class of diffusion-dilution problems relevant to underground mining practice. The equipment operations in underground mining are characterized by different activities with different time duration s, i.e. varying duty cycles. Therefore the volume and quality of diesel emissions and consequently, instantaneous concentrations are quite variable. Design of mine ventilation systems under these conditions becomes complex. In this paper, the development and use of mathematical models of mine production system, the engine exhaust air quality and engine exhaust transport in the design of ventilation system are discussed.IntroductionThe turbulent diffusion of suspended matter in an atmosphere is not only a topic of considerable intrinsic interest to the mathematical physicist and meteorologist, but also a problem of great practical interest. Release of particulate matter into the atmosphere at large has created o ne of the acute problems of the present day. Pollution of environment by industrial and domestic smoke, fumes and grit is widespread and has necessitated extensive studies in order to determine the concentration and distribution of pollutants in various areas. Pollutants discharge from stacks, whether chemical or radioactive, give rise to similar, but more localized, problems. The laws which govern turbulent diffusion in the atmosphere are also applicable to the study of the diffusion of toxic gases and the deposition of radioactive dust from nuclear explosion.The dispersion of diesel contaminants into the mine atmosphere is but a variant of a general class of diffusion-dilution problems relevant to underground mining practice. Most of the mine air pollutants, such as respirable dust, methane, diesel exhaust, and blasting fumes are produced in the face areas and haulage ways. Understanding of their dispersion in the mine airways is important to calculate their concentrations. In this paper, the development and use of mathematical models of mine production system, the engine exhaust air quality and engine exhaust transport are discussed. The over-all objective of this research effort is to evaluate the impacts of dieselization on production and ventilation systems and to aid in mine planning and design, as shown in the flow model in Figure I."

Jan 1, 1983

By J. E. Nesset, E. R. Bobicki, K. L. Bilaniuk

The introduction of froth flotation technology in Canada, and in particular, in British Columbia, began not long after it was successfully applied in the Broken Hill mining area of Australia which began around 1905. It proved to be a revolutionary and transformative technology that resulted in marginal operations in copper, lead and zinc becoming profitable in spectacular fashion. The paper presents the technology of both oil flotation and froth flotation in the context of the challenges of the time and its early application in British Columbia at the Le Roi No.2 mine (1903), the Britannia Copper mine (1912), and at the Allenby concentrator of the Copper Mountain mine (1918-19). New-found archival documents indicate the Britannia application to be the first production application of froth flotation for copper ore outside Australia, a claim that is currently made by the Braden mine (now El Teniente) in Chile. Flotation was initially an add-on process following gravity methods but was rapidly shown to be far superior method for the bulk and selective recovery of metal sulphides. Flotation proved particularly successful for the recovery of zinc sulphide (the so-called ‘zinc problem’) which was considered a contaminant at the time. The ‘copper problem’ related to the poor recovery of fine copper sulphide particles that were not amenable to gravity methods. The success of flotation led to changes in both the scale and methods of mining, concentration and smelting in a manner that allowed integrated mining companies to flourish. Many are still with us today. INTRODUCTION The advent of froth flotation in the early 20th century was truly a revolutionary technological development, not only for the mining and metallurgical industries, but arguably more so for business and society overall. The Canadian technology historian Jeremy Mouat stated (1996) “The development of flotation was the greatest single metallurgical improvement of the modern era...it is not overstating the case to claim that flotation was of central importance to the smooth functioning of the global economy”. It should, therefore, be a story of interest to us all. The aim of this paper is not to retell the full story, that has been well covered by others (Hoover, 1912; Rickard, 1916a; Hines & Vincent, 1961; Lynch et al., 2010) but rather to add some Canadian perspective and the key role played by companies and individuals in those early days, focusing on events in British Columbia’s copper industry. EARLY DEVELOPMENTS During the later half of the 19th century, a number of flotation-related patents were issued. These include the 1860 patent (Britain) granted to William Haynes for a process to separate sulphides from ground ore by mixing it with oil (1-10% wt) followed by a separation process in a water-filled vessel; the 1877 patent granted to Georg and Adolph Bessel (Germany) for a process involving the mixing of oil and graphite ore followed by boiling in water to produce a high grade graphite froth (>90% carbon); and the 1885 patent granted to Rebecca ‘Carrie’ Everson for the separation of sulphides by mixing sulphide ore with small quantities of oil, and adding water followed by sulphuric acid. These processes are more properly referred to as bulk oil flotation due to the relatively large quantity of hydrocarbon used.

Jan 1, 2019

By G. Robert Guillet

"Ontario enjoys the advantage of its proximity to the large industrial market of northeastern North America. Together with Quebec and fifteen nearby U.S. states, an industrial base of more than half the total for both countries is provided by a population of 100 million.Mineral fillers such as barite, calcium carbonate, kaolin, mica, silica and talc are of major importance in the manufacture of paper, paint, plastics, rubber, vinyl tile, carpet backing, putty, caulks, sealants and adhesives. Ontario has all of these minerals, but domestic production falls short of demand in some cases, and mica and kaolin are not produced at all.This paper reviews the market and outlines the distribution of the major filler-consuming plants of northeastern North America. It also identifies the principal producers of filler minerals in the United States and Canada.IntroductionOf all the uses for industrial minerals, mineral fillers are probably the least understood. Originally used primarily to add low-cost bulk to a variety of commodities without seriously affecting their properties, filler minerals have become essential components that enhance and extend the properties of their hosts. Hence the term ""extender"" which, for all practical purposes, is synonymous with ""filler"". Today, fillers and extenders are not solely low-cost additives, but ingredients that provide essential characteristics to the products they fill.The major markets for mineral fillers are paint, paper, plastics, rubber, adhesives and floor coverings. But there are many others: putty, pesticides, wire and cable coatings, caulking and asphaltic compounds, oilcloth, wall-paper, joint cements, inks, sealants and many others. Barite, calcium carbonate, kaolin, mica, silica and talc are among the more important filler minerals discussed in this paper, but there are at least a dozen others. And the increasing practice of coating the mineral surfaces with certain coupling agents or metal stearates is constantly expanding the range of characteristics and hence the marketing opportunities.Whiteness, particle shape, fineness of grind and cost are the principal considerations in selecting a filler, but other characteristics such as weight, opacity, hardness and chemical inertness may be dominant considerations in specific applications."

Jan 1, 1987

Bahuerachi Project Characteristics Why it?s nicer at Bahuerachi Mexico is a mining country Low political, regulatory and trade risk Low social/permitting risk Proximity to infrastructure Road Power grid (8 km) Rail line (25 km) High grade zones (skarns), CRD and near surface oxide component are sweet spots to the overall system. Size of low grade system points to potential long mine life?and numerous new targets developing. Timelines-2006? 90 to 100 combined RC and core holes to go! MAIN ZONE Drilling ? Goat ?Finish Mid April ? Main Zone, going North, depth of testing dependent, estimated for May ? North Lobe-May ? Commission independent resource estimate by May 06 for results of first pass drilling to date ?tonnesand grades ?Main Zone Milestone. ? Continue infill or expanded drilling to July (minimum) ? 1stpass RC scheduled until September OTHER Targets ? Begin drill testing North Skarn target Mid-April, minimum 5 drill holes, 1,000 meters. Ongoing expansion of target with surface work (mapping) ? Road to Colome(Skarnin north of Main Zone) as part of porphyry program ? Tule(southern) porphyry and skarn system-soils and mapping OUTSTANDING events Metallurgical report on floating and leaching tests (Sulphide/oxides).

May 1, 2006

By G. Gabra

"A process of leaching niobium oxide from pyrochlore concentrate using hydrofluoric acid is described. Variables such as acid concentration, temperature, reaction time, solid/acid ratio, agitation speed and particle size are correlated to the recovery of niobium oxide.The relatively low activation energy (1,86 Kcal/mole) and the dependence of reaction rate on agitation suggest that the process is diffusion controlled. The optimum conditions for extracting niobium oxide from the leach solution, using either methyl isobutyl ketone or tributyl phosphate have been determined.IntroductionMost of the commercial production of niobium and tantalum has been derived from the treatment of columbite - tantalite minerals.In recent years (1960) , pyrochlore mineral has been found to be an alternate source of niobium . This mineral varies widely in composition and contains in addition to the main elements of calcium , sodium and niobium, some tantalum, fluorine, rare earth elements, titanium, alkali an d alkaline earth elements.It is well known that the province of Quebec possesses several pyrochlore niobium deposits totalling approximately 151 million ton s at an average 0.45% niobium oxide(1). One of the deposits, the St-Honor carbonatite, was brought into production by Niobec Inc. in 1976. Flotation o f this material produces a concentrate of about 60% Nb205(2).In view of an expanding niobium market in recent years and the presence of large niobium deposits in the province, a research and development program was initiated at the Centre de Recherches Miner ales to evaluate known processes for the separation of niobium and tantalum from each other as well as their purification . Some work has also been undertaken at the CRM to develop an improved extraction process. T his work will be the subject of further communication s."

Jan 1, 1985

By Jan Butra

In copper ore mines located in the Pre-Sudeten Monocline the deposit mining using room and pillar systems has been carried out for more than forty years. When implementing mining systems in deep copper ore mines it appeared to be necessary to adapt them to variable geological conditions and natural hazards. In the initial period of exploitation there were mainly caving and rockburst hazards. The adaptation of room and pillar system was connected with a state of knowledge in the scope of identifying, forecasting and controlling rock mass hazards. The new solutions allowed the safe and efficient exploitation of a blanket deposit of variable thickness from about 2 to 15m, seated on progressively increasing depth. They included exploitation in constrained conditions, such as in protective pillars. In the exploitation period, technical and organisational activities aimed at rockburst hazard control were introduced including active methods for controlling rockburst hazard and procedures for conducting mining works in the rockburst hazard conditions. When mining at a depth exceeding 1,200 m, the exploitation method and technique are additionally affected by thermal hazard and by gas and rock breakout hazard. New solutions of the room and pillar system and a longwall system with mechanical mining have been developed for exploitation in the associated hazard conditions. The require application of many innovative solutions in the scope of mining process and ore haulage mechanisation, excavation support and forecasting and control of existing hazards. The main purpose of these solutions is to conduct the safe and economically effective exploitation of the deposit.

Aug 1, 2013

By G. Girard, A. Larouche, J. Colbert, G. Doyer

"The Direct Chill (DC) casting process uses water to extract heat from molten aluminium and helps to control the solidification process. Many factors such as the water flowrate, water distribution around the mould and water impingement angle have significant impacts on the solidification process. It has been noted that the chemistry variation of the cooling water is also an important factor that has a major impact on the presence of defects on the ingot. A significant change in the water quality can produce defects on the ingots such as cracks, bleedouts, or runouts. Understanding the impact of water quality variation on ingots is therefore essential to ensure good ingot production and reduce defects. This paper aims at describing a new approach to follow the variations of process water quality over time. It is an original and innovative method, which is still under progress. A water quality and stability index (WQSI) is under development to evaluate changes in the water composition based on water physico-chemical parameters. The index is calculated by comparing each of the actual parameters with historical values previously modeled by a statistical law. It is a dimensionless number having an adjustable weight factor for each parameter. The positive or negative contribution of each parameter, with respect to the water cooling capacity, is taken into account to calculate the WQSI. The current selection of parameters is based on knowledge from the literature as well as on empirical experience. When the developed tool will be mature, it could be used to track water variations upon time and anticipate problems, enabling proactive actions to ensure good ingot production.INTRODUCTIONFor many years, the impact of water chemistry on heat transfer, during DC casting, has been of great interest in the aluminum industry. Several papers have been published to demonstrate the correlation between water chemistry and heat transfer (Yu, 1985), (Gildemeister, 2014). Although numerous studies do present the effects of water parameters (i. e. hardness, conductivity, oil, and grease…) on cooling capacity under controlled experimental conditions, they do not reflect the strong interactions between the parameters and variations present in a casting center. Wells and Cockcroft also demonstrated that laboratory based studies are not fully representative of real heat transfer in an industrial casthouse, there are too many factors involved (Wells, Li, & Cockcroft, 2001). In this context, it becomes very difficult to obtain a quantifiable relationship between the capacity of water to cool the ingot and ultimately the performance of the cast."

Jan 1, 2016

By Daniel D. M. Adams

In 2004, Rio Tinto started a major project to implement Mine Monitoring and Control (MMC) systems worldwide. A detailed selection processes was undertaken and migration to a standard system was started. Today systems are operating around the world and serve as the core of to many business processes. Implementations include highly union areas, large mines, centrally managed mines, and remote areas. Each implementation has unique challenges but all are working towards the common goal with common systems. This paper reviews two projects that Rio Tinto has deployed in diverse conditions. The projects are the Rossing Uranium upgrade from the original Wenco system to the common standard and Iron Ore of Canada?s general technology upgrade. Also discussed is the future of mining at Rio Tinto, specifically the drill automation projects, and how it is utilizing the common standard MMC systems.

May 1, 2010

By J .. R. Brown, G. Deschenes

X-ray Photoelectron Spectroscopy (XPS), X-ray Diffraction (XRD) and Electron Probe Micro-Analysis (EPMA) were used to characterize chemically the gold complex adsorbed on activatedcarbon from a solution containing 102mglL Au and 0.5 giL thiourea. This paper also considers the gold chloride and the gold cyanide systems. The results indicate gold is adsorbed on activated carbon from the thiourea solution as the gold (I) thiourea complex, i.e. Au [CS (NH) 2];' Other gold species such as metallic gold were not detected on the carbon support. These results also suggest the elution of the gold (I) thiourea complex can be performed with high recovery.

Jan 1, 1993

By Jose R. Hernandez-Aguilar

"This paper revisits data from previous studies (Hernandez-Aguilar, 2010, 2011) to better understand the link between metallurgical performance and bubble size (Db) in the collection (pulp) zone of full-scale flotation systems. To obtain conclusive evidence exclusively related to the collection zone, the experiments were designed in those studies to control both the bubble generation method and the influence of the froth zone on the overall metallurgical performance in industrial and pilot-scale flotation columns. The results showed that generating small (1 mm) bubbles had a significantly higher beneficial effect on the recovery of coarse (> 75 µm) particles compared to the effect on fine (< 16 µm) particles. It was observed that, under certain practical conditions, the recovery of liberated coarse particles was close to zero, but could be recovered almost completely by reducing bubble size. The evidence revealed an apparent inconsistency of the so-called “k–PSb” model: at constant froth recovery, increasing Sb did not always result in higher recovery, as the model predicts. Overall, the evidence showed that it was not the Sb but the bubble size that proved to be a more reliable link to metallurgical performance. Only under highly suboptimal bubble size conditions (Db = 3 mm) did the froth zone seem to play a role, possibly reflecting an effect of pulp-zone bubble size on froth stability. However, for the most part, both the bubble generation method and the froth zone played inconsequential roles. An empirical model that better describes the kinetics of particle collection is proposed.INTRODUCTIONStudies showing the link between metallurgical performance and the interactions of bubbles and particles in the collection (pulp) zone of industrial flotation systems are scarce. A common belief among a number of mineral processing practitioners considers that “small” bubbles are favourable to recover “small” particles and that, conversely, “larger” bubbles are more efficient at floating “coarse” particles. However, perceptions like this are often substantiated by anecdotal evidence rather than by rigorous data analysis. What is the optimum bubble size for a particular case, how operating conditions can be adjusted to control a target bubble size, and whether the bubble size needs to be changed in the first place to optimize the operation of a flotation plant are questions that usually remain without solid answers.The studies reported by Hernandez-Aguilar (2010, 2011) were, in part, performed to test the effect of bubble size on flotation response and, thus, help address some of the above questions. The focus of the studies was to optimize the metallurgical grade-recovery performance of the Cu-Mo separation plant at Teck’s Highland Valley Copper mine (HVC). The outcome was compelling and significantly valuable: consolidated production data showed that in 2008 – the year when the recommendations from the studies started to be implemented – the Mo plant recovery was 89%, and gradually increased to 92% and 94% in 2009 and 2010, respectively, along with an increase in Mo concentrate grade. (Note: these production figures were not included in the publications quoted above; however, they were shown during an oral presentation at the 43rd Annual Meeting of the Canadian Mineral Processors in 2011.)"

Jan 1, 2016

By L. S. Jen

Canadian copper, nickel, zinc, lead and molybdenum mines are characterized by the mining of ores from which more than one metal is recovered. During the 1980s, approximately 15% of the gold, 25% of the zinc, 30% of the copper, 55% of the molybdenum, 80% of the silver and 90% of the lead produced from Canadian mines were produced as co-products and by-products of base metal mining operations. This trend is not expected to change significantly in the near future. The presence of co-products and by-products affects the level of production and the level of revenue from base metal mines in several ways: (I) in general, production of one base metal cannot be expanded or cut back without affecting the amount of production of another metal;(2) the commercial success of certain base metal mining operations depends on the substantial bonus revenues from co-products and by-products; (3) the quality and economic viability of many ore deposits are significantly improved by the presence of co-products and by-products; and (4) while coproduction is critical to the survival of some mines, bonus revenue from by-products can also be life saving to others during economic downturns. For these reasons, deposits with significant co-product or by-product values are likely to continue to be significant targets for exploration and for acquisition.

Jan 1, 1992

By P. L. Claessens, S. Belisle, C. Bowen

"Use of zinc shot feed is a well-established procedure among North American electro-galvanizers. This form of zinc is easy to handle and relatively inexpensive when compared with zinc oxide. This paper reports results on the kinetics of zinc shot dissolution in traditional pure zinc solutions and in electrolytes used for the plating of nickel/zinc alloys. Despite the cementation of minor amounts of nickel in the latter solution, acceptable dissolution rates of the zinc shot can be achieved through proper adjustment of the solution velocity. Under these conditions, the nickel shell produced by cementation is continuously abraded, exposing the underlying zinc.IntroductionThe use of insoluble, noble metal-containing anodes rather than soluble zinc anodes for the operation of high current density electro-galvanizing lines has gained almost universal acceptance. Two major reasons for this trend are:• improved control of the process by virtue of constant inter-electrode distance; and• increased productivity because the operation of the lines does not require the relatively frequent interruptions for replacement of consumed anodes .The results of the principal anode and cathode reactions are, respectively, depletion of the zinc content of the electrolyte and the increase on its acidity;"

Jan 1, 1991

By J. Dubinski

This paper describes the key circumstances of the underground coal gasification (UCG) process, which is planned to be carried out in the Polish hard coal mine ?Wieczorek?. The construction and field tests of a UCG pilot plant have key issues that need to be addressed to realize the research project goal: the elaboration of a highly effective technology of fuel and electricity production. The project will conduct several monthly tests of gasification in the pilot geo-reactor, which will be constructed based on the results of laboratory tests. The realization of the process requires numerous appropriately prepared actions adjusted to natural conditions in the hard coal deposit. Based on scientific principles, it is necessary to elaborate the procedures related to the location of the UCG installation (including its legal and safety aspects), and to perform a technical risk analysis. In addition, it is necessary to determine the required mining, geological, technical, economic and organizational circumstances, while at the same time considering the real but constantly changing process conditions.

Aug 1, 2013