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By Gordan Marrs, O. Matwijenko

"The Kidd Creek metallurgical site has been highly integrated to maximize revenues from its base metals mines. The site's operations include a Concentrator processing 4.3 million tonnes per year of copper-zinc ore, a Copper complex producing 100,000 tonnes per year copper cathode and a Zinc Plant producing 130,000 tonnes per year of zinc metal. To improve operating efficiency with increasing emphasis on productivity, process control, process automation and process optimization have been augmented and expanded during the last decade.New microprocessor based control systems provided the opportunity for the capturing of an expanded number of process related measurements. As supervisory computers were already in place, databases could be generated with only increased disc space and database management programs required. Once the data had been accumulated and stored, a method was then required for handling, screening and sorting large volumes of information in relatively quick and easy terms in order that the stored information could be used. By 1984, a decision to use personal computers for accounting, engineering and management reporting provided the vehicle necessary to handle this data. Using commercially available software, large volumes of stored process data can be downloaded from existing databases, filtered, sorted, analyzed, graphed, displayed, projected, reported and distributed. All this can be performed in very little time."

Jan 1, 1989

By G. Couture, J. -F. Dubé, F. Letarte-Lavoie

"The Xstrata Nickel Raglan concentrator, located in Quebec’s Nunavik region, has been in operation since 1997. Originally designed to process 800,000 tonnes per year of high-grade nickel ore, the plant’s current capacity is 1.3 million tonnes per year due to various optimization projects. In 2011 and 2012, the Metallurgical group, with assistance from BBA, updated and optimized the variables affecting SAG throughput in order to optimize process stability while maintaining maximum plant throughput. This project consisted of reviewing the control strategy and completely updating the pre-existing Fuzzy Logic controller. This paper describes the successful update of the controller including a complete revision of control rules, a new process control strategy and the integration of new process variables, most notably mill rotational speed. It will also show how this new approach has provided a simple and robust way of delivering both an increase in throughput while reducing process variability.INTRODUCTIONThe Xstrata Nickel Raglan Mine concentrator is located in Northern Quebec along the 62th parallel. It has been in operation since 1997 and was originally designed to treat 800,000 tonnes of ore annually. The Raglan Agreement held with the Makivik Corporation and the Inuit communities limits the annual tonnage of ore that can be processed at 1.32 million tonnes.The ore is processed in a 24 foot variable speed, semi-autogenous grinding mill (SAG). The conversion from Autogenous Grinding (AG) to SAG was completed in 2006. Before the ore is processed by the SAG, its size is analyzed by a Wipfrag camera that provides a granulometry estimate. A cone crusher reduces the SAG’s discharge screen’s oversize material. A 14 foot diameter ball mill ensures final grinding before the flotation stage.Many control strategies were used at the SAG over the past few years. Fuzzy Logic was first used in 2007 in order to control tonnage feed to the SAG. This first version only measured the value of the variables without taking into account their rate of change. Revisions were made over the course of the last few years to improve controller performance. Other variables were added such as slurry density and crusher Closed Side Setting (CSS). The previous revision of the Fuzzy Logic was done in 2009 with a review of the rules only."

Jan 1, 2013

By Ernest Baafi

A simulation model RoadSIM using the ARENA modelling system has been developed to evaluate roadway development options for a given development panel configuration. The RoadSIM simulation system has provisions for variability/randomness in operations including cutting and loading at the face, tramming and discharge of coal to the boot end and availability of equipment. The modelling system provides a means for assessing the operational limitations of roadway development practices at a particular coalmine. It is a ?what if? tool that allows a range of equipment, configurations and operating practices to be assessed in terms of achievable advance rates and equipment utilisation. Output from the system is in the form of a dynamic visualisation as well as summary reports and detailed logs of operations over time.

Oct 1, 2009

By E. V. Konopleva, H. J. McQueen

Steels in high variety have been providing strength and ductility for more than a century mainly through complex heat treatments following hot shaping. The economical and sustainable goal was a steel with the two operations combined through applying knowledge of dislocations and strengthening mechanisms aided by new mechanical and microstructural techniques. Primary hot reversing-mill rolling produced static recrystallization (SRX) between every pass to significantly finer grain size. Hot torsion showed that with lay-on temperature and rate of reduction suited to gradual precipitation of minor additions of Nb, the austenite grains would become highly pancaked; the existence of very fine subgrains along the grain boundaries (GB) could be deduced from tests on stainless austenite. The HSLA strip had to be water-jet cooled immediately to prevent SRX at austenite GB and ensuring complete transformation to ferrite avoiding grain growth after coiling. Confirmation on old mills and successful product led to the design of more flexible mills for wider range of compositions and products. A significant one was auto bumpers that reduced crash damage. More crack-resisting compositions were developed for strip welding into line pipe for arctic oil transport. Lower metal consumption and easier fabrication has resulted in more sustainable welded bridging.

Jan 1, 2015

By J. A. McLennan

Geological uncertainty is an unavoidable characteristic of all mining projects since only limited information is available from sampling. Mine planning and development decisions with significant economic consequences are made when the geological heterogeneity is inherently uncertain. Geostatistical simulation is preferred over kriging because the methodology provides alternative property realizations that can be combined into a model of geological uncertainty. Geological uncertainty can be transferred into production uncertainty, which can help characterize the economic risk of the project. This paper presents a case study for the Pogo property, being prepared for development near Fairbanks, Alaska. The exact dimensions, grades and production predictions have been modified; however, the methodology is illustrative. The geostatistical methodology consists of (1) assembling the relevant drillhole data and establishing a suitable coordinate system, (2) calculating the target distribution, (3) creating a model of spatial correlation, (4) generating multiple realizations at a small scale and (5) linearly averaging all the realizations to the chosen selective mining unit (SMU) support size. The geostatistical model is then used to calculate production uncertainty.

May 1, 2004

By R. D. Lawrence

"Suggestions have been made that the appraisal of mining assets using discounted cash flow techniques should be based solely on proven and probable reserves in reliance upon the widespread international recognition of uniform resource definitions. Following a review of general accepted valuation principles, a survey of the literature and, most importantly, a review of real transactions in the open market, it is clear that valuators should not be constrained by the growing acceptance of modern mineral resource codes. On the contrary, valuation practitioners should be encouraged to examine all classes of mineralization and, after making due allowance for risk, to utilize all mineral resources as a basis for determining fair market value.INTRODUCTIONGreat strides have been made recently in achieving an international consensus on mineral reserve and resource definitions and classifications. The Australasian JORC code, the CIM code in Canada, the SME proposal in the United States and even a proposed code from the United Nations have all brought the objective within reach.Unfortunately, this success has led to another problem for mineral valuators. Certain securities regulators, tax collectors and their ilk have begun to expound on the opinion that discounted cash flow projections carried out to calculate net present values that would form the basis for a valuation determination should be based solely on proven and probable reserves. The author disagrees with this position. This paper examines the subject from four points of view:"

Jan 1, 2003

By K. N. Subramanian

Previously reported work on total oxidative leaching of chalcopyrite concentrates ha s shown that high copper extractions are obtained at 210°C and 0.4 MPa oxygen pressure. A simple integrated flow sheet using pressure leaching, solution treatment involving precipitation with a calcium base, and electrowinning to produce wire-bar-quality copper is described. Reagent and energy requirements developed from this work indicate that the process could be attractive for small operations where a smelting-refining complex cannot be justified.

Jan 1, 1978

By Ken Dyck Sr.

"Construction of the Cigar Lake uranium mine in northern Saskatchewan is well under way. Production is anticipated to begin in the first half of 2007. When in full production, the mine is projected to produce a net 18,000,000 pounds of U3O8 per annum from a high grade ore averaging approximately 20% U3O8.Water management was a major issue that required substantial effort in the Cigar Lake design. Not only is effluent quality controlled, a tight water balance to minimize effluent volume is also designed into processes in order to minimize environmental impact. This paper focuses on the water treatment process and water handling equipment, as well as the operating philosophies that will reduce fresh water consumption to a minimum. An overview of the mining and ore handling systems, as well as aspects of controlling water production from the ore formation and the mine development areas will also be discussed.INTRODUCTIONThe Cigar Lake ore body has proven and probable reserves that total 232 million pounds U3O8. Cigar Lake is the world’s largest undeveloped high-grade deposit. It is the second largest highgrade deposit surpassed only by the McArthur River deposit another Cameco - operated mine in the Saskatchewan Athabasca Basin. Cigar Lake is owned 50% by Cameco Corporation, 37% by AREVA (COGEMA Resources Inc.), 8% by Idemitsu Uranium Exploration Canada Ltd. and 5% by TEPCO Resources Inc. When production starts in 2007, ground ore slurry from Cigar Lake will be shipped to the McClean Lake mill (owned by AREVA) some 80 km away. All of the Cigar Lake uranium will be leached from the ore at McClean Lake. During initial production ramp up, all uranium will be processed at McClean Lake to yellow cake (uranium oxide). After the average production has exceeded a 10 million pound per year rate, Cigar Lake uranium will begin to flow from the McClean Lake Mill to the Rabbit Lake Mill. At this point, subject to regulatory approval, 57% of the Cigar Lake uranium, in a uranium rich solution, will be transported to Rabbit Lake mill (owned by Cameco) for purification to yellow cake. A complete summary of the flow of uranium from the Cigar Lake ore body through to product at both McClean Lake and Rabbit Lake can be found in a recent paper titled “The Cigar Lake Project – Mining, Ore Handling and Milling” in the March 2004 issue of the CIM Bulletin. The paper was written by C.R. Edwards."

Jan 1, 2006

By H. W. Parsons

Several low-temperature, dry chlorination processes for the treatment of sulphide minerals are reviewed, in a chronological order. These processes include the following: the Swinburne-Ashcroft, Baker-Burwell, Maim, Comstock-Wescott (Aldermac) and the Mitterburg Mining Process. Dry chlorination investigations at the Canadian Mines Branch (now CANMET) and the U.S. Bureau of Mines are discussed, as is a proposed process by the South Africa National Institute for Metallurgy. The techniques used in the process are discussed, as are the shortcomings, problems and failures of the methods.

Jan 1, 1978

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 Peter A. Hacquebard

Recent drilling programs have shown that the in-situ coal resources of Nova Scotia are very substantial. The grand totals of the measured, indicated and inferred categories amount to 232 m, 646m and 993 m tons, respectively. This vast quantity of coal occurs essentially in five main fields: Sydney, Mabou, Port Hood, Pictou and Springhill. The largest resources (84% of the total) occur in the submarine area of the Sydney coalfield. With a 65% recovery rate, there are at present 150m tons of proven, recoverable coal in Nova Scotia. At a predicted maximum annual production of 5 m tons, this amount equals a lifespan of 30 years. However, additional drilling, particularly in the Sydney offshore area, holds promise of increasing the recoverable reserve tonnage to at least 350 m tons. This figure may be compared with the 484 m tons production obtained during 191 years of mining (from 1785-1976). The geological appraisal of the remaining coal resources in the five fields mentioned is presented in three-dimensional diagrams, per individual seam and corresponding reserve area. In addition, the submarine extensions of the Sydney and Mabou coalfields are discussed in light of results obtained from off shore oil exploration wells. The terminology and standards of coal resource calculations are pointed out, and the phenomenon of seam splitting and its prediction from geological data is illustrated. The availability in Nova Scotia of either thermal or metallurgical coal is considered in relation to rank and sulphur content. This paper was presented in June 1977 at the 90th Annual Meeting of the Mining Society of Nova Scotia. The coal resource estimates, however, have been updated to include the results obtained with the offshore drilling in the Sydney Coalfield to November 1977.

Jan 1, 1979

By J. Suarez Condezo, E. Herrera Alarcon

The Ilo Smelter Modernization Project will require treating the slag from the Peirce Smith converters in Slag Cleaning Furnaces using pig iron technology. Currently the slags from the converters show variable magnetite contents. The copper contained in this slag is recovered in Reverberatory Furnaces, where the smelting rate was improved due to the high silica content of the converter slag. Preliminary industrial tests where developed to clean the slag from converters using pig iron. The results showed that the magnetite content has a significant influence in this process. This work describes the actions that are being implemented in the converter operation to control the magnetite content in the slag in order to maintain the high copper recovery of the smelter when the new facilities are commissioned. This task will demand a strong control of both the slag chemistry and converter practices in order to get the copper recovery considered as the design criteria (~97.4%).

Jan 1, 2007

By Sengpasith Houngaloune

Arsenic, which is a toxic and carcinogenic element, causes serious environmental problems throughout the world. It is also known as a major contaminant in the non-ferrous mining and extractive metallurgical industries, thus its disposal is one of the most important environmental issues for the mining and metallurgical industries. In order to ensure a safe disposal environment for the final wastes, stabilization of arsenic has been studied extensively with various approaches. Solidification/stabilization (S/S) represents one of the most effective methods to reduce the availability of arsenic in soil and waste by transforming toxic or potentially hazardous phases into less hazardous ones. Cement based S/S processes could reduce the solubility of arsenic in solid waste, using inorganic binders such as cement, lime, and pozzolanic materials. A new tailings management technique, called cemented paste backfill (CPB), has become widely employed for improving mining techniques and for tailing storage purpose and this technique could also enhance arsenic stabilization, by fixing the contaminants in the binder matrix. Disposal of arsenic in the form of scorodite (FeAsO4?2H2O) has been widely accepted as currently the most suitable method for stabilization and the safest known storage material. The Bio-scorodite process has been reported to be more economic and environmentally friendly method than the chemical crystallization processes. Retention of arsenic by schwertmannite (Fe8O8(OH)6SO4), a metastable ferric oxyhydroxy sulfate mineral, has gained more attention in the recent years. Schwertmannite has a large specific surface area and high capacity to adsorb arsenic in solution. Several researchers have reported that the transformation of schwertmannite to goethite could be retarded by the presence of adsorbed arsenic; therefore schwertmannite might be viable alternative for long-term storage of arsenic. In this paper, various approaches used in arsenic stabilization are reviewed with emphasis on the development in the recent years.

Aug 1, 2013

By H. C. L. Reemeyer

"The mining industry faces increasing economic, environmental and social challenges, as easier deposits deplete and ores become more difficult to mine and process; head grades decline; projects migrate to increasingly remote and difficult geographies; and the industry faces more stringent environmental and social standards. While these factors increase costs and risks, they also present opportunities for a more integrated approach to mining, processing, materials handling and waste management. Two key areas of risk are in tailings and water management. As mining and processing tonnage rates continue to increase, the disturbance footprints, water and energy consumption and scale of tailings storage facilities also rise. These factors can be mitigated by more selective mining, ore sorting and pre-concentration, and more intensive tailings dewatering. Such alternatives must be considered in conjunction with the selection of mining method, metallurgical flowsheets, major equipment selection, and key process design criteria. For example, increasing the grind size of a concentrator reduces energy consumption and eases tailings dewatering, but may cause challenges with metal recovery. Emerging technologies will be reviewed, and economic and environmental trade-offs for eco-efficient alternatives will be presented for metal sulfide mines.INTRODUCTION The metals mining industry faces significant challenges that can affect its financial viability and social license to operate. There has been a consistent decline in ore grades and a relentless push towards larger operations to capture perceived economies of scale. With these larger operations, the environmental footprint of mines has increased. Water and energy consumption, and resulting GHG emissions have also risen. In recent years, two issues have raised special concerns for stakeholders and companies: • Water scarcity, particularly in drier regions of the world such as Northern Chile, SW USA, Southern Africa and Australia • Tailings risks, following the high-profile failures of the Fundao tailings dam in Minas Gerais, Brazil in 2015 and the Mount Polley tailings dam in BC, Canada in 2014"

Jan 1, 2017

By W. R. Smith

Introduction No commercial deposits of silica sand are known to occur in British Columbia, so all requirements for foundry and other uses must be imported. During the war, nearly 5,000 tons per year were used, all originating in Illinois and delivered to local consumers for about $12.00 per ton. Present requirements are somewhat less, but the cost is still of the same order. The relatively high cost of silica sand in British Columbia is not only a serious item for present consumers, but might be a deterrent to the establishment of a glass industry, should this be contemplated at any time. The present investigation was undertaken in an attempt to provide a cheaper source of silica sand within the Province. In 1936, a large number of beach and bank sand deposits in the lower coastal region of British Columbia were examined by the British Columbia Department of Mines, and samples were analyzed chemically and mineralogically. The deposits over the whole area proved remarkably uniform in mineral composition, consisting essentially of quartz, feldspar, ferromagnesian minerals, rock fragments, and various accessory minerals, and differing only in the relative proportions of the various constituents. In no case did the quartz content of any sand exceed about 40 percent and the average was of the order of 20 to 30 percent.

Jan 1, 1947

By C. Jay Hodgson, P. J. MacGeehan

"The gold ore zones of the Campbell and Dickenson mines occur within a km-wide, 2 km-long zone of highly altered and anomalously fissile and deformed volcanic and subvolcanic intrusive rocks, cut by a series of mainly post-deformation mafic and quartz-feldspar porphyry felsic dykes.Three main periods of gold ore-forming hydrothermal activity are recognized. In the first, the mine rocks were extensively altered and gold and arsenic enriched; syn-volcanic auriferous veinlet and low-grade chemical sedimentary ores were deposited in what was a major discharge zone of a submarine hydrothermal system. The chemical sedimentary ores are closely associated spatially and temporally with domal rhyolitic extrusions. Because of its mechanical and chemical properties, this synvolcanic alteration zone became the locus of later deformation, and the site of the generation of auriferous hydrothermal solutions, perhaps by pressure solution processes at depth. These solutions deposited, synchronously with deformation and metamorphism, the second and most economically important type of ore zones in the mine: large foliation-parallel and foliation-oblique banded carbonate- 'chert' Rssure-filling veins.In the third and final mineralizing event, high-grade, pipeshaped zones of siliceous replacement-type mineralization, and quartz-arsenopyrite-gold veins, were superimposed on the previous mineralization types after most of the deformation, but before the emplacement of the late dykes. The source of heat and also possibly the fluids for the third mineralizing period may have been the dyke-forming igneous activity. The textures and mineralogy of the banded carbonate- 'chert' veins suggest a near-surface (<3 km) environment of deposition, but their relationship to the fabric of their host rocks indicates they were emplaced in an environment, presumably at considerable depth (5-10 km?), in which the rocks were undergoing intense penetrative deformation. This anomaly is unresolved."

Jan 1, 1982

By R. L. Stanton

"The present contribution is complementary with a preceding one on the field association of the conform-able ""pyritic"" deposits. It considers the more important features of their mineralogical constitution and their microtextures, re-examines the present interpretations of these, and of-fer-some alternative explanations. The term ""pyritic"" for these de-posits is m many cases a misnomer, as two quite distinct ore types are inuolve. One is a banded pyritic sphalerite-galena-chalcopyrite ore (for which the term '•pyritic"" is in-deed quite suitable), while the other is non-banded and is composed essentially of pyrrhotite and chalcopyrite. In addition to these constitutional differences, each is distinctive in general appearance and texture. The occurrence of two such consistent but clearly distinguishable ore types is attributed -rather than to difference in source material and pressure-temperature conditions of deposition -to the contribution of similar source material to dissimilarly oxygenated environments of sedimentation. Textures in the banded ores generally thought to be indicative of replacement or of high-temperature exsolution are explained by slow, law-temperature segregation in situ during compaction, folding, and regional metamorphism."

Jan 1, 1960

By W. J. Witte, M. K. Witte

"The purpose of this report is to present a generalized preliminary design and cost estimates for a typical heap leach operation such as might be undertaken in Northern Ontario. This report should be of value to anyone in the mining industry planning, or contemplating, a heap leaching operation in Ontario, either on a large or small scale. While more detailed costing and design work will obviously be required for each specific project being contemplated, the data provided in this report should enable parties to make preliminary estimates of the costs of proposed projects and should identify most of the planning and design parameters that will need to be considered.Although heap leaching has been used extensively as a low cost gold recovery method in other parts of the world for many years, it has only recently become of interest to the Canadian mining industry.In order to investigate and demonstrate the feasibility of using heap leaching in Ontario, the Ontario Ministry of Natural Resources in 1982, undertook to locate a private sector proponent willing to undertake a 10,000 ton demonstration project. This project was to have been carried out at a production scale under normal northern Ontario field conditions. The Ministry was to have provided technical management and design for the designated project."

Jan 1, 1985

By Steven Townend

Mining-related activities have been known to create a challenging operating environment for mining companies located in close proximity to communities. Issues such as noise, vibrations from mining operations, land use and emissions are often a concern for community residents. In order to develop good community relationships it is necessary to take a proactive approach. This paper documents this approach and also deals with the social implications for Vale associated with mining activities in the heart of the community of Copper Cliff, Ontario, Canada.

May 1, 2011

By James R. Hunter, Sandra K. Zacharias, Ursula M. Franklin

Archaeometallurgical remains can be a valuable source of information about past technological activities and, by inference, the societies that undertook them. Material traces of former metal-producing or metal-working centres can include raw materials, products, or metallurgical installations such as mines, furnaces or forges. Of these remains, the most common is slag, often left undisturbed since its original production. Physical and chemical analyses of archaeological slag and metal can often reveal the processes and materials involved in their formation. Mineral composition and softening temperature of a slag, for instance, can indicate the conditions of the metallurgical operation, such as temperature and atmosphere and, thus, help identify metallurgical processes which took place at a site(1). The present report illustrates the value of such analysis. Metal-working remains from Sainte-Marie among the Hurons, near Midland, Ontario, on the south side of Georgian Bay have been analyzed in order to determine the techniques and processes used by the 17th-century blacksmith who worked at the mission headquarters from 1642 to 1649. Samples were selected from a very large collection of blacksmith refuse which was excavated from the site by archaeologist Kenneth Kidd in 1941-42(2).

Jan 1, 1999