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By Maryam Sadeghi, Jonathan Roy, Claude Bazin

"The operation of mineral processing equipments is intimately related to the mineral composition of the ore. However unit performances are usually characterized in terms of metal contents or recoveries as this data is easier to obtain than the mineral contents. This paper describes a method that combines the operations of material balancing and estimation of the mineral contents of the ore. The estimated mineral contents can be used for process analysis and diagnosis of operating problems.IntroductionThe ore that is feeding a concentrator is made of minerals that condition the energy requirements for the ore comminution and the performances of the subsequent separation circuit. Indeed a change in the mineral composition of the ore may lead to lower grinding mill throughput as well as lower recovery or grade of the economical products. Despite this relationship is recognized the mineral composition of the ore is seldom measured or estimated to provide regular information for the diagnosis of operating problems. Some methods such as the QEM-SCAN (Whiten, 2008; Lamberg and Vianna, 2006) are available to measure the concentration of the minerals in ore samples but the method is time demanding and plant operators usually base their evaluation of the plant performances on chemical assays of metals or elements since this data is easier to obtain from ore samples.Usually samples of the streams of mineral processing plants are collected on a daily basis to be assayed for strategic elements. The obtained concentrations are balanced to produce coherent data with the material conservation constraint and then used to characterize the day to day operation of the plant in terms of recovery of valuable metals and grades of the marketable concentrates. The behavior of contaminant elements can also be monitored from this data allowing the operators to explain for instance a lower zinc concentrate grade by a more important contamination of iron. However such diagnosis is only partial as the contaminant element can be transported by different minerals. Indeed the iron contamination of a zinc sulfide concentrate may be caused by an inadequate depression of pyrite or due to another iron carrying mineral. A possible way to answer the question is to determine the concentrations of the various minerals in the ore and produced sealable concentrates. Since measuring the mineral contents of the ore could be a demanding task one should consider to estimate this data from the daily chemical assays of the sample collected on the main streams of the circuit. Some authors have already investigated the problem. Whiten(2008) described a method to estimate the mineral contents of an ore sample. Lamberg and Vianna(2006) proposed a method to do a sequential mineral reconstruction followed by a material balance. Few of these methods account for the mass conservation of the reconstructed mineral contents."

Jan 1, 2016

By B. E. Shaw

This paper describes the use of the Free Piston Valve, and a simple hoist brake control system, which has been developed over the last two years, greatly improving the performance of low-pressure brake engines. The basic control system is outlined, with sections devoted to emergency trips and differential braking, and the application of the system to deep shaft hoisting is discussed.

Jan 1, 1966

By David S. Wong

With air emission limits for total particulates continually tightening, management of `potroom dust' or airborne particulates from aluminium smelting potrooms is of increasing importance. To better understand how settled and airborne particulates are generated within a potroom, methodologies have been developed to sample and analyse the compositional signature of dust, in relation to its sources. During a smelter case study, these methods allowed tracking of mineralogical phases in dust across a range of potroom locations, showing that the mechanisms of dust generation do vary spatially and vertically in a potroom. Such methodologies may also be applicable to other metallurgical industries.

Jan 1, 2011

By Guangyuan Li

A 3-D block-spring model (BSM) has been developed for simulating the behaviour of jointed rocks. The model uses a discontinuous formulation and an iterative procedure to solve the large displacements in jointed and faulted rock masses. The 3-D BSM has been used to simulate mining excavations in jointed rocks around an open pit and underground settings. The applications have demonstrated that it is a practical tool to solve complicated problems of rock mechanics in civil and mining engineering. This model has recently been modified to incorporate complex geological conditions, such as underground water flow (seepage), unstable blocks and the time-dependent behavior of backfill materials. To demonstrate the capability of the 3-D model this paper presents the fundamentals of the 3- D BSM and its application for open-pit mining. A complete computer package BSM3D has been developed based on the 3-D block-spring model. The package consists of a solving engine for numerical analysis and a Windows based processor for mesh generation and results display. The multi-functioned pre-processor provides tools and menus to help users setting up models easily and conveniently. The fully featured post-processor allows users to view the results in different windows and orientations. The graphical results include contours, vectors, animation of rock movement, and the failure state of the rock structures.

May 1, 2001

By M. Abdellatif

Successful demonstration of The Mintek Thermal Magnesium Process (MTMP) was achieved in November 2004 at the pilot-scale, About 30 tons of magnesium producing recipe was smelted in the DC arc furnace over a continuous operation of 8-days, Twenty-two furnace batching-tapping operations were carried out at a feed rate of 525kg/h and a smelting temperature of 1600-1700°C, The MgO content in the produced slag was as low as 6,7%, and averaged 9,2% MgO, resulting in an overall magnesium extraction of 77%, which reached 87% during good operating periods, Magnesium vapour was extracted at a rate of 70-85kg/h and was delivered to the condenser that was operated at 680-720°C, The magnesium was captured in the condenser crucible in a liquid state, allowing its prompt tapping, More than 3500kg of crude metal were produced over 15 on-line metal tapping operations, On average, a condensation efficiency of 85% was achieved during the entire testwork, which peaked at 87% during steady operations, The quality of the crude metal was similar to, if not better than, that of the Magnetherm's crude magnesium, A pre-feasibility study has indicated that the MTMP has the potential for lower capital and operating costs as compared to the electrolytic process, and therefore Mintek and its consortium partners are exploring opportunities for a commercial production facility.

Jan 1, 2006

By M. Askari, A. Ahmadi

"This study was conducted to establish the possible application of bioleaching in the pilot scale to recover valuable metals from the sulfidic tailings of Golgohar Iron Mine (Kerman, Iran). Using bioleaching processes, solvent extraction and sulfide precipitation recovery of valuable metals including, copper, cobalt and nickel from the tailing was investigated. The results showed that the optimum pH and temperature conditions relative to the bioleaching step was 1.5 and 45°C. The extraction of the metals from the low grade polymetal resource with complex mineralogy is very important from economic, environmental and technical point of views. Moreover, the proposed method has some advantages from energy saving, tailing management and creating added value from waste materials aspects.INTRODUCTION The growing demand for base metals and strategic such as: copper, nickel and cobalt as well as high-grade resource depletion has caused them, the mining industry to extract metals from low-grade resources and driven by complex mineralogy (Xie et al., 2005). Economic extraction of metals with low grade sources requires low-cost and efficient processing methods. A source with enormous potential for metals in future, secondary sources, such as: tailings mineral industries which the lack of appropriate technology and the high cost of processing weren't recoverable with previous procedures in the past. But it is possible that with develop new and efficient technologies have the economic exploitation ability. Recovery of metals from tailings resources is very important not only in terms of precious metals but also in terms of reducing environmental problems (due to heavy metals). The metals of copper, nickel and cobalt are mainly like sulfide compounds in the nature, usually for their recovery, first they make ore with flotation method to obtain the sulfide concentrate that containing valuable metals. then for the metal production, it will be melt and purification. Due to the environmental aspects, technical problems in the recovery of base metals from low grade ore and mixes, the presence of small reserves, in the past three decades they pay much attention to the use of hydrometallurgical processes for the recovery of base metals from these resources. These processes are classified according to the solver agent to leaching sulfates, chlorides, nitrates and amines (Hackl, 1995). Early, chloride leaching under oxidation condition in acidic or alkaline solutions was recognized the best process to produce sulfide concentrates. But then the basic processes sulfates was considered as the superior process because of being easier, a better understanding of the chemistry of leaching and recovery of base metals, especially copper from the environment easier sulfate solution with an organic solvent extraction and electro winning. The bioleaching is shown its ability on a commercial scale of low-grade sulfide minerals and ore that because of environmental reasons, the possibility of melting is not possible to them. The existing industrial base factories are based on primarily on the bioleaching and pressure leaching and recovery of cathode copper sulfate solution by extraction with organic solvents (SX) and electrowinning (EW) (Wang, 2005). Preliminary analysis has shown that valuable elements such as copper, nickel and cobalt are in the float flotation unit. Hence the plan to extract these metals from the wet tailing stream has been done."

Jan 1, 2017

By L. H. Bergmann

THE blasting practices described are fairly representative of those employed in the coal mines of Eastern Canada. As such, they may be of interest to Western Canadian coal mine operators. The treatment of the subject is general, no attempt being made to discuss blasting operations at any particular coal mine in detail. All the mines dealt with are mining bituminous coal and are classified under the Coal Mines Regulation Act of the Province of Nova Scotia as 'closed light' mines. As such, they are required to use only 'permitted' explosives and to apply them in a 'permitted' manner, except where authority is given by the Mines Department to do otherwise.

Jan 1, 1945

By J. Doucet, C. Price

In an industrial setting, operational changes are continually introduced, driven by new technologies or changing economics. Because of day-to-day variability, quantifying the impact of these changes based on metallurgical performance requires long trial periods to achieve statistically significant results. Tools and techniques developed by the mineral processing group at McGill University have allowed for direct measurement of process variables (e.g., bubble size, gas and solid holdup). Two case studies are described where direct measurement techniques were used to evaluate: a) a new rotor stator mechanism; and b ), the introduction of a new frother type. Application of these methods has accelerated the evaluation of process changes and improved confidence in results.

Jan 1, 2009

By L. Henry Smith, David C. Arthur

"The Williams Mine is Canada’s largest gold producer, with annual production of 450 000ounces from 2 300 000 tonnes of ore. Highly mechanized and automated underground mining practices are employed in order to achieve and maintain high levels of productivity and minimize costs.The mine ventilation system is modified to include a new vent raise and variable pitchvane-axial fan. This addition allows several fan installations underground to be decommissioned. A substantial net savings in installed horse power is achieved.Heating costs associated with under-ground ventilation air are a significant portion of mine operating costs. Air heating costs are substantially reduced by recovering heat from upcast exhaust air, minewater and compressor cooling circuits. This waste heat is used to supplement propane fired air heating systems for underground ventilation air. An additional benefit is the availability of a heat sink for summer cooling of the compressors.System design, energy savings data and payback calculations are presented."

Jan 1, 1996

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

By F. Fournier Dit Chabert, F. Tancret, J. François Castagné, R. Le Gall

During the repair of turbine blades by a laser cladding process, it is observed that interdendritic cracking occurs in the heat affected zone (HAZ). Auger electron spectroscopy, performed on sample broken at high temperature, reveals interfacial sulfur segregation, which is known to be one of the main causes of microcraking in the HAZ during welding processes. Moreover, thermal gradients generated by the process are responsible for important thermomechanical stresses. In the present work, the finite element code Comsol Multiphysics is used to simulate the laser cladding process in order to determine both the thermal field and, using an elastoplastic law, the stress field inside the component. The originality is that the temperature history calculated in the thermomechanical model is extracted then injected in a segregation model in order to calculate the local segregation behavior. This model can be eventually used to predict the risk of cracking as a function of process parameters and alloy chemistry.

Jan 1, 2006

By Nav Dhadli

Tailings from Oil Sands MiningWhat are they? Challenges Solutions Regulatory Environment Definition of the AFD Tailings Treatment Process 2010 AFD Pilot/Demonstration ProgramTechnical challenges Performance and Results Next steps Oil Sands Industry Collaboration on Tailings Technology TAILINGS ?WHAT ARE THEY? Mixture of remaining water and solids following bitumen extraction process Composed of water, sand, silt, clay, small amounts of hydrocarbon (bitumen, solvent, and asphaltenes) A necessary part of production in excavation of oil sands and removal of bitumen

May 1, 2011

By N. Ogbonna, D. G. Dixon

Although heap bioleaching has been recognized as an economic alternative for treating low grade mineral ores, the underlying physical, chemical and biological processes involved are complex. A detailed investigation into the dynamics of heap bioleaching processes has provided much insight into the underlying complexities, and has led to the development of a sophisticated modelling tool - HeapSim. This tool can be of great help in the design and operation of heap bioleaching processes. In this paper, the mathematical model implemented in HeapSim is examined. The model takes into account mineral kinetics, particle level effects, bacterial growth, oxidation and adsorption, gas absorption, pore diffusion, bulk advection, gas balance and heat conservation. Three case studies where the model has been applied are briefly discussed. Computational Analysis in Hydrometallurgy 35th Annual Hydrometallurgy Meeting held in conjunction with the 44th Annual Conference of Metallurgists of CIM Calgary, Alberta, Canada Edited by

Jan 1, 2005

By Charles Camsell

THE Northwest Territories covers a very large area-more than one-third of all Canada-and its most northern point, Cape Columbia in Ellesmere island, is distant only 500 miles from the Pole. Our first knowledge of the Arctic Archipelago, of which Ellesmere island forms a part, resulted from a gold-mining venture in Queen Elizabeth's reign. The English navigators of that time were eager to find a north-westerly and shorter and Jess hazardous route to the riches of China and Japan than that which Magellan had discovered, but they were unaware that the continent then known to bar a direct route extended in great width far to the north. Frobisher was one of these navigators. He reached in 1576 the bay in Baffin island now named after him, convinced that he had found a passage connecting the Atlantic with Asiatic seas. Forced to re-turn after ordeals in which ice, wind, and Eskimos flayed formidable parts, he brought back, among other novelties, a piece o black stone which had been picked up casually by one of his officers, and gave a little of it to the wife of one of the venturers, or financial backers of the enterprise. To quote now from Hakluyt: ? 'She by chance threw and burned it in the fire so long that , at length being taken forth and quenched in a little vinegar, it glistered with a bright marquesset of gold. Whereupon the matter being called in sorne question, it was brought to certain goldminers in London to make assay thereof, who indeed found it to hold gold and that very richly for the quantity." On the strength of this, the venturers, anticipating much profit, launched a second expedition to secure more of this stone, and 143 persons, including 14 miners and finers, set forth in 1577 and returned the same year, with, however, 200 tons of another mineral. Influenced by glowing accounts of veritable mountains of this mineral and by assays made after "additaments"-that is how "salting" in those days was described-the venturers, including Elizabeth, supplied funds for erecting a smelter and refinery at Dartford and outfitting a stilllarger expedition. And so, in 1578, fifteen ships departed with the Queen's blessing, for the same remote shores. After many mishaps, they returned with over 1,000 tons of the mineral, but when it yielded very little of value at the works in Dartford, the? Company of Venturers was forced into liquidation. Though our first prospector and miner was rather inconsiderate of the investors, he proved the existence of an archipelago, hitherto unknown, and secured much information about the new land and its dwellers.

Jan 1, 1938

By N. W. Hendry

ABSTRACT Exploration by geophysical methods and diamond drilling of an occurrence of chrysotile asbestos, located ten miles east of Matheson, Ontario, was commenced on March 25th, 1949, by the Canadian Johns-Manville Company, Limited. The asbestos is associated with a narrow sill-like body of basic and ultrabasic rocks which strikes northwesterly across portions of Munro and Beatty townships. To date, asbestos zones of commercial interest, many hundreds of feet in length, width, and depth, have been outlined by diamond drilling along a 2-mile length of serpentine. The fractures occupied by the asbestos veins are closely associated with the regional faulting in the area. The mining of the first occurrence, or A orebody, will be by open-pit methods. Milling will commence at a rate of 50 tons an hour. INTRODUCTION OCCURRENCES of chrysotile asbestos in Munro township have been known at least since 1914 and references to them appear in reports published by the Ontario Department of Mines in 1915 (1) and 1919 (2). J. G. Ross (3) in his excellent publication on Chrysotile Asbestos in Canada, mentions an occurrence in Munro township. The area was first mapped in detail by J. Satterly, of the Ontario Department of Mines, in 1944, and brief mention is made of chrysotile asbestos in Satterly's preliminary report (4), which was published the following year.

Jan 1, 1951

By Gerald Blackmore

"This paper suggests that with the settlement of long-term contracts of fifteen years' duration, with prospects of extension, the coal mining industry has, for the first time, a complete commercial justification for large-scale planning.The labour costs of coal production over past years are analyzed and, with the acceptance of the premise that the basic shift rates are certain to rise in the years to come, the paper suggests that forward planning should provide &r capital investment to make a traditionally labour-dense industry into a capital-dense industry.Automated methods of manpower deployment and timekeeping and the monitoring of all equipment back to a central control point are discussed as ail-important means of obtaining maximum utilization of high-cost capital investment.Principles of payment of the work-force, and the utilization of equipment 24 hours a day, seven days a week and the maximum number of days a year, are dealt with as means of achieving maximum capital utilization. Some of the new technical underground and coal preparation problems which will undoubtedly result from the concentration of workings and maximum machine utilization are discussed, and the author makes suggestions as to how these might be solved.In short, the author predicts that if the coal mining industry is prepared to recognize the problems and invest in modern equipment backed by highly trained staff. then the outcome will justify the high capital investment involved. He stresses the importance of human communications in achieving this end."

Jan 1, 1970

By A. K. Verma

This paper provides a brief overview of evolution of deformations, stresses, and pore pressures due to different excavation stages during construction of an URL. Excavation of a rockmass develops a damage zone of finite width around the excavated zone which is associated with changes in permeability and which affects the fluid flow mechanism. In this study, a coupled hydromechanical (HM) analysis has been conducted for a water saturated porous rock mass which has been created by sequential excavation and backfill of vertical disposal pit of an URL. For this purpose, an Atomic Energy of Canada Limited?s in-floor concept for a deep geologic repository suitable for Indian conditions has been used. Changes in rock deformations, stresses, strains and mechanically induced pore pressure in an undrained condition, during excavation, as well as those caused by mechanically induced rock deformations after backfill of the disposal pit, have been modeled. A three-dimensional finite difference tool FLAC3D has been used for the analysis.

Jun 1, 2012

By D. E. Wakefeld

"My first reaction to Joanna LaForte’s discussion paper is that she has quite properly assumed that I would like the process of equitable participation between aboriginal landowners and mining companies to be a fast process. On the other hand, I have been a business lawyer long enough to know that the past experiences of the parties will have a significant effect on how they will proceed at any one time.In my article, I was trying to convey the importance of responding to the wishes, aspirations and fears of aboriginal communities in Arctic regions without land settlements. I agree that if it is necessary to wait for governments, the process will be quite slow. My article did point out that often aboriginal communities and mining companies who have become comfort-able that a project is in their mutual interest regard the government(s) involved as their common enemy. I agree that the education and training of aboriginals should “expedite the negotiations and end the power struggles equitably”. Also, I did not mean to suggest that the elders distrust of changes in traditional land use was solely due to concern for alienation and separation from their offspring; however, I suspect it is one reason for their caution. I also agree with this author that establishing opportunities that enable the young aboriginal community members to remain in the north and avoid the problems that await them in southern urban culture should be a common concern of the mineral developer and the Arctic aboriginal community.When this author suggests I am “overly concerned about how much land the aboriginals will control, how educated they may become, how ignorant they are of mining procedures, how objections from aboriginals will escalate expenses, etc.”, she attributes to me as “concerns” matters that were intended to be general information for my readers. My references to the increased land holdings and the improvement in education of aboriginal peoples was intended to deter mining companies from any attempt to be inequitable in their dealings with aboriginal communities."

Jan 1, 1996

By M. A. Clayton, D. Kinakin

The Mitchell Creek Landslide is a large, structurally controlled, complex bedrock instability located in northwestern British Columbia. Characterization of the landslide using aerial photograph, exploration geology, and geotechnical investigation data has been completed allowing the development of a three dimensional conceptual model of the landslide domains and slope behaviour. Three domains have been identified in the landslide, from top to bottom: the Sliding domain, a relatively intact slab slowly sliding into the valley; the Transition domain, located in the mid slope of the landslide and showing evidence of significant extension and continuing to subside and displace into the valley; and a Toppling domain, at the toe of the landslide in an area of overturned foliation. Movement is greatest in the Toppling domain, with long term estimated rates of movement up to 4 times that of the Sliding domain; the Transition domain exhibits the greatest range of displacement rates, with average long term values approximately double the slower Sliding domain. This paper documents the results of numerical modelling of the Mitchell Creek Landslide with variation in geomechanical properties, basal rupture surface configuration, structural fabric, and pore water pressure conditions. The locations of internal shear surfaces within the landslide have been estimated from surface scarps, structural fabric orientation, and borehole monitoring data. The performance of each numerical model was evaluated against observed behaviour of the landslide. The configuration and properties of the basal rupture surface were identified as critical to model behaviour, as was spacing and location of internal structures.

Jan 1, 2015

By D. J. Hallbom

This paper presents a novel methodology for the hydraulic design of mine backfill distribution systems. The ?operating range? method uses the concepts of the hydraulic grade line and equivalent pipe length to determine flows and pressures as the pipeline route and static head change over the life of the mine. The operating range method is easy to learn because it is semi-graphical and uses well-known design concepts (e.g., the hydraulic grade line) and slurry design models (e.g., the Durand deposition velocity model). However, by changing the paradigm in which these concepts are used, the operating method allows all potential pipeline cases to be analysed simultaneously without the need to know the exact pipe routing. It also allows the hydraulics engineer to quickly identify ?pinch points? and ?slack flow? zones, to estimate the effect of changing the size or length of any given section of pipe, to assess the impact of changing the material properties of the backfill slurry, to size the slurry pumps, and to size and locate rupture discs when required.

May 1, 2007