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By Charlie Harper

Open Pit Mining of Golden Band Resources? EP Gold Deposit Golden Band Resources Inc. (GBN:TSX-V) is Saskatchewan's newest Gold Producer. Located in the La Ronge Gold Belt of northern Saskatchewan, GBN has over 875 km2 of claims with 12 known gold deposits and 4 former producing mines. Production has begun at the Roy Lloyd Mine (Bingo Deposit), to be followed initially by our EP and Komis properties. Development of the underground infrastructure at the Roy Lloyd Mineis continuing and on schedule. Production from these deposits will feed our centrally located and 100% owned Jolu mill. We have our provincial environmental permits in place, and we have an established infrastructure including a 400 tonne-per-day mill, year-round road access, and access to grid power. Construction of the grid power line and the above ground tailings facility are now complete.

Nov 1, 2011

By A. Warczok

Chalcocite concentrate obtained by magnetic separation and flotation of Bessemer matte is processed in the Inca top blowing bottom stirring MK reactor into semi-blister copper. The semi-blister is then converted into blister copper in the multi-purpose vessels (MPV) by oxidation of iron, nickel and sulphur. High melting point NiO and Fe30 4 are formed inside the MPV s, which together with Cu20 and smaller amount of fayalite are the major constituents of the solid mush. The accumulation of solid mush and buildup requires periodic MPV cleaning by adding reductant and copper-nickel matte, a unique process called "washout". Various reductants and their combinations, such as pig-iron, 15%Si Ferro-silicon and 50%Si Ferro-silicon, have been used for the reduction of solid mush and buildup. The possibilities of using calcium carbide as a reductant and slagging flux were examined experimentally at the crucible scale. The rate of reduction of MPV buildup was determined by continuous measurement of CO and C02 contents in the offgas and the flowrate of argon carrier gas. The rate of the buildup reduction with calcium carbide was approximately five times faster than the rate of reduction with coke. Additionally, the formation of CaO results in the melting of reduced buildup and formation of a slag at 1300°C and higher temperatures. It was found that simultaneous silica addition enhanced the melting and slag formation. The results showed the strong dependence of the reduction rate on temperature. Activation energy is approximately 225 kJ/mol. Expected benefits of using calcium carbide are related to cost saving on reductant, significant acceleration of solid mush reduction, and reduced amount iron input from reductant.

Jan 1, 2007

By T. Banerjee, Y. Dumais, R. Lemire

"Agnico Eagle LaRonde produces over 300,000 ounces of gold annually, along with silver, zinc and copper by-products. The LaRonde plant consists of a conventional SAG and Ball mill circuit, followed by flotation. Load management is imperative for maintaining stability in grind size and ensuring consistency of the flotation feed. In flotation, the mass pull profiles of the cells and reagent dosage rates need to be managed to maximize recovery, while maintaining product quality. This is achieved by controlling the air, level and reagent addition set-points across the circuit. However, disturbances such as feed size distribution, ore hardness and mineralogy make it challenging to maintain efficient control using traditional control techniques. LaRonde therefore worked to develop a progressive control strategy, targeting stability and optimization. This started with a year-long instrumentation upgrade campaign, focusing on optimizing the performance and reliability of plant-wide instrumentation. The process was then optimized, leveraging AwaRE advanced controllers running in closed loop with PARC modules embedded within the PLC. The installation of 8 PFC cameras in flotation changed the flotation operation from a level and air control based strategy, to one that controls mass pull. This new control philosophy has allowed the plant to effectively manage mill load, improving grind size and providing increased throughput with better flotation performance.INTRODUCTION Background Since 2015, Agnico Eagle LaRonde has been conducting an optimization campaign to maximise the performance of plant assets leveraging instrumentation and control. The grinding and copper flotation circuits were identified as the areas having the greatest opportunities and value proposition for advanced control. A disciplined approach was followed to design and implement a progressive control solution to achieve operational excellence."

Jan 1, 2018

By P. R. A. Andrews

"Graphite is one of the most versatile of non-metallic minerals because of its diversified properties, for example: it is unctuous; it marks readily; burns slowly; is almost chemically inert; is flexible over a large temperature range; is a good conductor of heat and electricity; is hydrophobic; has a negative temperature coefficient of resistivity; has excellent weathering properties; tends to emulsify with water-in-oil; is readily soluble in iron; and after oxidative treatment, can exfoliate like vermiculite. These properties give rise to its major uses in lubrication, refractories, marking instruments, electrical products and paints.Flake graphite is the variety which commonly occurs in Canada; the provinces of Ontario and Quebec contain the deposits of economic significance, although graphite occurs in other provinces. The beneficiation of graphite has been the subject of many investigations at CANMET, thus reflecting graphite 's importance as an industrial mineral. Thirty-eight studies relating to various aspects of beneficiation were conducted between 1918and 1989anda review of some of the more important studies is presented. The information includes mineralogy, beneficiation methods and results; flotation parameters and reagent concentration data are presented in tabular form. By so arranging the principal data, the research worker and production metallurgist will be assisted in the evaluation of graphite ores from a variety of origins."

Jan 1, 1992

By M. L. Wacker

"Cigar Lake high-grade uranium mine in Saskatchewan is operating after 25 years of test mining, construction, and mine flood remediation. Factors include ground stability, groundwater control, radiation exposure, and ore handling. A 10 year test program resulted in validating “jet boring”, a non-entry mining method involving artificially freezing the orebody and surrounding rock; tunnelling to develop access crosscuts below the orebody; installing cased pilot holes through ore; extracting ore using rotating high-pressure water jets within pilot holes; and cavity concrete backfilling. Ore slurry is prepared underground, pumped to surface, and trucked to McClean Lake mill for processing to uranium concentrate.RÉSUMÉ Après 25 années d’essais sur les méthodes minières, de construction et d’assainissement suivant les inondations à la mine, l’exploitation de minerai à haute teneur en uranium Cigar Lake, localisée dans la province de la Saskatchewan, est opérationnelle. Les principales difficultés concernent la stabilité du terrain, le contrôle des eaux souterraines, l’exposition aux rayonnements et la manutention du minerai. Un programme d’essai de 10 ans a abouti à la validation du « forage à érosion », une méthode minière qui consiste à congeler artificiellement le corps minéralisé et les roches environnantes ; à creuser des tunnels pour développer des travers-bancs d’accès en dessous du corps minéralisé ; à installer des puits de fondation pilotes à travers le minerai ; à extraire le minerai à l’aide de jets d’eau à haute pression dans les puits pilotes ; et à remblayer les cavités avec du béton. La boue de minerai est préparée sous terre, pompée vers la surface puis transportée par camion jusqu’à l’usine de concentration de McClean Lake pour le traitement afin d’obtenir du concentré d’uranium.INTRODUCTIONThe Cigar Lake deposit is in northern Saskatchewan, 660 km north of Saskatoon, Saskatchewan, Canada, at the east edge of the Athabasca basin (Figure 1; Bishop, Mainville, & Yesnik, 2016). The operation is jointly owned by Cameco Corporation, AREVA Resources Canada Inc., Idemitsu Canada Resources Ltd., and TEPCO Resources Inc. Cameco has been the operator of Cigar Lake since January 2002. The discovery hole was drilled in 1981. Commercial production was declared in May 2015 and the Phase 1 operation will have a mine life of 15 years."

Jan 1, 2017

By W. Curlook

"A review is presented of a growing number of imperatives, some self-imposed, some imposed by society, which the mining and metals industry faces in carrying out its business. These imperatives bear on all activities from the exploration phase, through engineering, design, plant construction and operation, to decommissioning.IntroductionThe mining and metals industry must learn to cope with, i.e. manage, a growing number of imperatives. Some of these, such as the need for responsible stewardship of natural resources, the requirement to respect laws and regulations, the need to provide for safe and healthy workplaces, and the need to provide appropriate returns to investors of capital , have been with the industry for a long time (fable I). But the industry now faces additional imperatives that are growing in number and in importance (fable 2):• There is the growing concern about the impact of operations, not only on the workplace environment and the external environment, but also on the need to monitor not only the chemical concentrations in various effluents but to also monitor the effects of such emissions on the environment; i.e. there is a growing concern about the ""net"" consequences of operations.• There is the need for on-going improvement in productivity and safety to compete and survive in a global economy. The global business environment has become paramount.• There is the imperative to failsafe all designs, equipment and operational procedures, and having done that to provide for containment of unavoidable spills, and to have ready and in place systems for emergency response.• There is the need, indeed the imperative, to involve all employees in various quality improvement programs.• There is the imperative to face up to ""virtual elimination/zero emissions""; and• One must have waste management plans in place to cope with the need to reduce, reuse, and recycle; and• There is the need for decommissioning plans for all operations, for the restoration of business habitats to their original states (or better). Indeed, one must engage in the decommissioning exercise from day one, i.e. right from the time of design and commissioning."

Jan 1, 1992

By M. Bélanger, H. -L. Jacob

"The province of Quebec has a strong tradition in industrial minerals. Ten commodities are produced and the annual total shipments have exceeded $600 million in recent years. Quebec is a world renowned producer of chrysotile, titanium slag, graphite, and ilmenite. Quebec is an important North American producer of mica, talc, and peat moss. This paper reviews the main minerals and commodities that have been the object of exploration or development in recent years, namely graphite, wollastonite, dolomite, and silica. Some of the leading projects concerning magnesium minerals and apatite-ilmenite are described. IntroductionQuebec has a strong tradition in industrial minerals. It goes back to the second half of the 19th century when the first graphite and apatite mines in the Gatineau area and asbestos mines in the Eastern Townships were opened. Since then, more than 25 commodities have been produced in Quebec, making industrial minerals an integral part of the Quebec mineral industry. Today, industrial minerals and building materials count for one third of the total mineral production in Quebec.Present industrial mineral production includes 10 commodities (Table 1). In the last five years, the value of industrial mineral shipments has varied between 500 and 700 millions dollars annually, which represents 20% to 25% of Quebec’s total mineral production. For many years, Quebec has been a major producer of chrysotile and titanium slag, the only producer in eastern North America of mica, graphite and ilmenite, and a leading Canadian producer of talc and peat moss. Quebec also produces, mainly for domestic markets, dolomite, limestone, salt and silica.Quebec’s industrial mineral sector has been quite active in the recent years. Exploration by government geologists and companies has led to the outlining of new deposits, some of which are now in production; others are currently being evaluated. Technical and economic studies are also underway to determine the feasibility of various development projects."

Jan 1, 1999

The University of New South Wales (UNSW) has been a world leader in the development of innovative virtual reality technologies over the last 10 to 15 years. These developments have included developing the world?s first 360° surround, virtual reality (VR), stereo projection theatre system known as AVIE (Advanced Visualisation and Interactive Environment), which was developed by iCinema, a collaborative venture between the UNSW Faculties of Engineering and College of Fine Arts. The UNSW School of Mining Engineering has been responsible for development of mining applications virtual reality software modules and to date, has developed eighteen different mine safety training and mining engineering education modules which run in the AVIE environment. This platform and technology package provides a unique ?immersive environment? experience for groups of trainees or students who can engage with the simulated environment in the complete safety of the virtual reality theatre. In all of the major international mining industries, safety is of paramount importance, and training of personnel is an essential component of any comprehensive proactive safety management system. All personnel need to be aware of the inevitable hazards around them at all times, as well as understand appropriate safety and operational procedures. This can be done by conventional class-room style training sessions, or by provision of training documentation. However the effectiveness of such systems is often very limited due to the inability of trainers to engage with the audience for a lengthy period of time; or to convey the often complex and variable mining environments and situations which can exist in a typical mine. The ability to immerse the trainees in a virtual mine environment, with all the reality of an actual mine but with none of the physical exposure to actual hazards, provides a far more effective and engaging training experience. Furthermore, in the virtual world, trainees can be exposed to the very unlikely, but nevertheless high consequence hazards such as mine fires, falls of ground or outbursts, without any risk to their safety and well-being. The end result is that trainees will be far more engaged with the learning environment they find themselves in, and will develop a far higher level of understanding of the topics, rather than simply experiencing a passive class-room style learning environment offered by conventional training modes. The UNSW systems have been implemented widely within the Australian mining industry and the mining engineering education sector and are now being adopted internationally. This paper presents an overview of the innovative technologies involved in these virtual reality systems ? as applied to the mining industry. Modules developed for both mineworker training and mining engineering student learning will be presented, to illustrate the effectiveness and value of such a training and education approach.

Aug 1, 2013

By J. Boldy

This paper is an attempt to place Canadian Precambrian volcanogenic deposits in perspective, by examining and compiling data regarding certain neglected fundamentals of size, grade, value, frequency distribution and spatial density. The discovery roles played by various exploration methods are compared and contrasted, and. using empirical methods, the probabilities of discovery are discussed, combined with the use of an effective 'cost-per-target' program. From these basic observations, realistic exploration judgments may be made. Using similar methodology, this format may be applied to other types of deposits. Precambrian volcanogenic deposits occur in a natural geometric progression in size. They number 110, of which 70% are pre-producers, producers or past-producers. These deposits are bonanzas and generally have a 'net pre-smelter' value of between $43 and $62 per ton. The statistically typical deposit is that which occupies the modal position, has 400,000 tons of ore, a value of $20 million and occurs with a frequency of 40%. A median deposit has 1.4 million tons of ore, a value of $70 million and occurs with a frequency of 15%. An upper-decile deposit ha s 13.3 million tons of ore. a value of $750 million and occurs with a frequency of 6.5%. The major, mid-upper-decile deposits have a minimum of 50 million tons of ore, a value of $3 billion and occur with a frequency of 4%. Five major volcanogenic deposits occur in the Precambrian and account for 54% of production. This contrasts with 55 deposits (all below the median) which account for 3.9% of production.

Jan 1, 1977

By M. H. Cullender

THE determination of the flow characteristics of gas wells depends upon the analysis of pressure data obtained under shut-in conditions and under one or more known flow conditions. These data are commonly referred to as back-pres-sure test data, and I know you are all familiar with the back-pressure equation where, Q rate of flow, Mcfd @ standard conditions C coefficient of the back-pres-sure curve P 1 formation pressure, psia P • sand face flowing pressure, psia P2 (psia)2/1000 n exponent of the back-pres-sure curve Figure 1 is a graphical presentation of the back-pressure equation; the coefficient is the rate of flow at a difference in squared pressures of 1, in this case 2250 Mcfd, and the exponent defines the manner in which the rate of flow changes with a change in the difference in squared pressures. In Figure 1, the exponent of the back-pressure curve is 0.554 which means that for a 10-fold change in the difference in squared pressures, there will be a 3.58-fold (10 raised to the 0.554 power) change in the rate of flow.

Jan 1, 1961

By K. D. Eng, W. T. Tierney

"During the past century, the development of vehicular transportation has benefitted tremendously from the performance improvement in engines in a situation where low-cost, plentiful fuel supplies were the order of the day. Engine advances were enhanced by and also dictated fuel modification to better adapt the energy source to the power plant.In discussing the several aspects of the change in approach from ""an engine and its fuel to a fuel and its engine"", the authors touch on the following areas:1. Description of an engine concept that provides the needed flexibility in fuel appetite at good efficiency to cope with future requirement s.2. The constraints placed on liquid fuel resource energy utilization efficiency by special engine-required fuel properties and the fuel efficiency of the various engine types available.3. Future vehicle engine fuel sources. This review will put into perspective the problem associated with the net energy available from future fuel sources under extensive research and development at present.4. A brief review of test data to show that fuel-tolerant and fuel-efficient engines are viable and that, in a fuel-resource-limited future, they can be a ""light at the end of the tunnel.""The Texaco Controlled Combustion System (TCCS)The TCCS is a unique means for stratified charge operation of an internal combustion engine in such a manner as to eliminate the requirement for octane or cetane number specification for the fuel. Octane rating is an empirical engine test method that evaluates a gasoline's resistance to spontaneous ignition or ""knock."" Cetane is based on a different engine test, which determines a diesel fuel's ease of spontaneous ignition . High cetane number enhances cold starting and permits high-speed diesel engine operation. As one would expect, the fuels in current use cover a band when the two values, octane and cetane, are plotted against each other."

Jan 1, 1982

By Chris Harris, Kamal Adham

The use of HCl acid is gaining momentum among hydrometallurgical processes. However, the issue of environmentally efficient and economically viable ways to regenerate HCl acid (from various metal chloride intermediate products) remains a technology and operational challenge. The authors provide a state-of-technology review based on Hatch’s years of testing, design and commissioning experience with high-temperature units (fluid bed and spray roasters), plus the recent efforts in the area of low-temperature HCl regeneration.

Jan 1, 2014

By P. R. La Pointe, J. Clark

"Studies have shown that the roof in coal mines is nearly twice as likely to fail at intersections as at entries due to enlarged roof spans, stress redistribution and other factors. However, the relative stability of intersections in a mine varies, and an improved understanding of what factors impact roof instability can lead to efficient, proactive mining practices that both enhance stability and mining efficiency.A study was undertaken at an underground longwall coal mine to develop a model to predict the stability at the intersections of entries and cross-cuts. The statistical analyses relied upon observational and measured data regarding the development of tension cracks, seepage, intersection geometry, mining practices, geological attributes and geomechanical factors at 783 intersections. Each intersection was given a NIOSH roof. Common data mining techniques, such as multivariate linear regression, multinomial logistic regression, decision trees and probabilistic neural nets, were considered and evaluated to establish correlations and associations between stability and the other variables. Two of the more successful techniques were Decision Trees and Multinomial Logistic Regression. The analyses showed that a number of factors impacted stability:• Overburden thickness (impact on stress concentration magnitudes)• Initial opening area (impact on stress concentration magnitudes)• Sulfur content (depositional environment & impact of mechanical properties, leaching effects)• Intersection type (impact on stress concentrations)• Gob distance (impact on stress concentrations)• Presence or proximity of a particular sandstone (impact on mechanical properties)• Roof bolt type and diameter (impact on reinforcement)Some factors showed no statistically significant relation to stability. These included:• Total area• Supported areaSeepage was a more problematic variable in assess. Seepage is associated with instability, but it is not clear whether seepage occurs as a consequence of instability, for example, through the creation of tension cracks, or whether the intersection has been excavated where water already exists and has degraded the rock prior to excavation, leading to greater instability.Seepage appears related to the geology of the roof rock mudstones, not the sandstones. Tension cracks in the intersections occur preferentially where the Sulfur content is below 0.9%. The Sulfur may relate to mechanical differences in the roof rock, and where the Sulfur is low, the roof is less stable, there are more tension cracks, and seepage is greater. This suggests that the weaker mudstones may be more prone the development of tension cracks, not because these rocks are more brittle, but possibly weaker.2-way and 3-way intersections appear to have less seepage than 4-way, although very few intersections overall have any seepage. This is similar to the roof stability, in which the 2-way and 3-way are more stable. 2-way and 3-way intersections have fewer-than-expected tension cracks, while 4-way have more than expected. These results suggest that four-way intersections are weaker and more prone to tension crack development, also suggesting that increased seepage results from weaker roof conditions, rather than the converse. Thus seepage appears to be mostly a consequence of instability rather than a cause and is higher where there are 4-way intersections, mudstone geology and external loading factors like depth of cover and proximity to gob that promotes crack development. The study also indicated that a better understanding of the mudrock facies could reduce uncertainty."

Jan 1, 2015

By J. Bouchard, A. Desbiens, M. Maldonado, R. del Villar

ABSTRACT: Despite many years of practical applications in mineral processing plants, the potential of column flotation has still not been fully exploited. The challenge in measuring some key variables is certainly an important contributing factor to this situation. Reliable online measurement of variables, such as the froth depth, bias, gas hold-up, frother concentration, bubble surface area flux, and bubble size distribution, provides opportunities for the application of various advanced control strategies and real-time optimization based on an economic criterion. For several years, Université Laval’sLaboratoire d’observation et d’optimisation des procédés researchers have been working on these opportunities. This paper describes the most recent advances and current research trends.

Jan 1, 2011

By E. Haccuria

Due to the growing share of electrical cars, the use of lithium ion batteries significantly increased. Recycling of these batteries is essential to safely dispose hazardous materials as well as to recover valuables (Cu, Ni, Co, etc.). In order to optimise the recycling process, accurate information is required on the slag phase equilibria for battery smelting. The slag is a multi-component system containing alumina from the battery cases, silica and lime from fluxes, and manganese and lithium from the electrode materials. The present study accurately determined the phase equilibria in the "MnO"-Al2O3-SiO2 sub-ternary system at metal alloy saturation. Particular attention was given to the accuracy and reliability of the final results by highlighting the different reaction pathways, mass transfer- and reaction mechanisms taking place in the system during experiments. This attention enabled improved experimental methodology and measurements. Based on the present study, further measurements will be undertaken in the quaternary "MnO"-Al2O3-CaO-SiO2 system at low "MnO" concentrations, which closely represents the future recycling industrial slags.

Jan 1, 2014

By R. E. G. Caines, P. Alport

"Operating heavy equipment in Labrador, where the winters are 8 months long and the temperature frequently drops below -40°F (-40°C) for days and sometimes weeks presents unique problems in both the operation and maintenance junctions. Winterization programs must be well designed and implemented at the proper time. These programs must include the proper selection of fuel oil, engine oil, hydraulic oils, greases, cooling system fluids, etc. More often than not, modifications have to be made to the original equipment in order that it can be operated safely and economically in the Canadian North. Manufacturers usually design equipment for a less harsh environment and the user makes adaptations by trial and error.Operators have to be trained for the proper operation on ice- and snow-covered roads in an open-pit mine. Special emphasis must be put on haulage road conditions. In this paper, the authors will cover some specific maintenance procedures, equipment modifications and operator training problems experienced by the Iron Ore Company of Canada in its open-pit operation in Labrador.IntroductionT he Iron Ore Company of Canada is engaged in open-pit mining , concentrating and pelletizing of iron ore. The company operates in two provinces, Quebec and Newfoundland (Fig . 1) . The Knob Lake operation "", based in Schefferville, Quebec, has mine sites located both in Labrador and Quebec . The Caro l Lake Project is situated in Labrador, 25 kilometres east o f the Quebec border at Labrador City. The Carol operation mines, concentrates and pelletizes it s o re before rail transportation to the seaport o f Sept-lies via the Quebec North Shore and Labrador Railway."

Jan 1, 1984

By M. Scobie, G. R. Baiden

"This paper describes recent developments at Inco Limited, Ontario Division, in the field of information systems for automated mining. A CA TV cable network has been combined with a broad spectrum radio antenna system to allow the supply of voice, data and video services to underground mining. The system formed the basis of a field experiment at the Copper Cliff North Mine of the Ontario Division in 1990.The experimental information system was developed to supply underground mining with voice, data and video services to mobile and stationary locations. In order to test the communication system, telephones and radios were linked together with the outside phone lines for voice communication. Stationary data was implemented on a SCADA (Supervisory Control and Data Acquisition) system for mine monitoring and control using PLCs (Programmable Logic Controllers), while using personal workstations for the mine planning and engineering functions. Stationary video was installed in the experiment to observe crushing, conveyor transfer points and skip dumping areas. Mobile data and video were tested by the teleoperation of an LHD. The functions supplied to the vehicle were monitored through a computer, with control being maintained through a standard radio interface and real time video pictures for the operation of the machine.This paper discusses the field testing of the information system and results achieved to date. It concludes by discussing the options considered to be open to provide information systems for future automated mining."

Jan 1, 1992

By J. W. Reynolds

"The use of approved fire-resistant hydraulic fluids in equipment operating underground was made mandatory in British Columbia by amendment to the Provincial Mines Regulation Act effective January 1, 1975. This paper covers the action taken to achieve this, in the largest underground metal mine in British Columbia. Some evaluation of costs and effects based on experience to date is included.BackgroundAn amendment to the Mines Regulation Act of the Province of British Columbia was passed in July 1974 as follow s: "" Rule 111 (b) Hydraulic Fluids. After the first day of January 1975, all hydraulic fluids used in equipment operating underground shall be of a fire-resistant type accept able to the chief inspector.""Unquestionably, its intent was justified as a safety improvement measure. The list of fires in mines involving machinery where hydraulic fluid was a factor in the fires is long and sobering. In British Columbia, in a 22-month period from 1972 to 1974, there were six fires in metal mines resulting in extensive equipment damage and injury to four workmen. Nevertheless, no provision was made for research or development of systems modifications compatible with conditions encountered in B.C. and, as late as June 1977, the Mining Association of British Columbia continued to argue that fire suppression systems should be considered sufficient until a universal suitable hydraulic fluid could be developed. The sole concession was to issue permits for continued use of mineral oil in equipment bought prior to 1975 in order to allow producing operations to continue. The burden of developing the necessary technology was laid on the industry.The Sullivan Mine at Kimberley, the largest and longest established underground mine in the province, and Cominco's most important source of ore s for its smelter at Trail, B.C., was at the outset of a conversion from conventional to trackless mechanized mining methods in pillar recovery operation s. Introduction of fire-resistant hydraulic fluid s had to be done in a period of change, in many instances on equipment for which no data existed, and called for research which had to be done while retraining the work force.The introductory phase is complete. All equipment is on FRF, the requirements of Rule 111(b) are being satisfied, and a number of research and development programs continue."

Jan 1, 1980

By Rodrigo Craig Cerello

The Brazilian economy has always presented a strong correlation with the mineral activity. Since colonization days, due to the territorial expansion caused by the explorers search for gold, mining in Brazil became a basic sector of national economy. Currently, the Brazilian mineral sector¹ estimates a 550% production increment (Figure 1A) in the last 10 years, reaching the US$ 50 billion value, reflecting the increased global demand for raw materials from mineral origin. According to the Brazilian Constitution², mineral resources belong to the Federal State and, consequently, their exploitation must be authorized, under penalty of engendering federal crime. Furthermore, activities of this nature are prone to cause environmental degradation such as, but not limited to, deforestation, pollution, soil deterioration and water contamination. The GPEMA represents the forensics group of the Brazilian Federal Police responsible for the technical analysis of traces related to crimes against the environment and consequently, illegal mining cases.

Aug 1, 2013

By E. Kouame, M. D. Everell, D. Hodouin, T. Kasongo

"To properly operate a mineral beneficiation plant it is often necessary to have systematic evaluations of the performances of a piece of machinery, of one of the processes or of the plant as a whole. The state of a process can be described from a collection of data: flow-rate values, particle-size distributions and chemical compositions of the various streams of the circuit studied.However, the obtained raw data are generally redundant and inconsistent from a material balance viewpoint, due to natural disturbances, sampling errors, unreliable instrument readouts and laboratory analysis inaccuracies.BILMAT is a computer program which upgrades mineral processing data, adjusting them in a least-squares sense in order that they may verify material conservation constraints. As a consequence, the program is able to calculate the best values of unmeasured flow rates (such as. circulating load ratios). BILMAT is a very general program in the sense that it can accept various data from any type of mineral processing circuit, and its usefulness is demonstrated here for three processing circuits of a pyrochlore concentration plant: grinding, desliming and flotation.IntroductionComputation of the material balance around any metallurgical process, that is the determination of stream flow rates and composition. is a basic step in its evaluation. In spite of the simplicity of the physical laws of mass conservation. and of the very fundamental need to know the flow of components around a process. it appears, particularly in mineral processing. that material balancing is quite often a difficult task. The reasons for this involve the problems associated with collecting measurements in mineral dressing plants. They are generally poorly instrumented and invariably data must be collected through hand sampling. Due to the heterogeneous nature of the streams, segregation occurs and samples are often not adequately representative, a problem made worse by the lack of circuit sampling facilities, which are often completely ignored by plant designers. Furthermore, the nature of the measurements to be performed (for instance particle size distributions in the fine range) frequently gives inaccurate results."

Jan 1, 1981