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By D. Lascelles, J. A. Finch, E. El-Ammouri

Flotation separation is expected to be related to the degree of dispersion of the pulp. For instance, highly aggregated systems may show reduced selectivity, reduced entrainment and increased flotation rate. In an attempt to test the impact of aggregation on flotation, we have taken advantage of the effect of Mg ions. Using combinations of Mg2+ and pH gave a wide variation in aggregation of several Cu-Zn ores (measured by settling rate) and corresponding flotation response was determined by batch tests. The trials were conducted on-site at Louvicourt and Agnico-Eagle. In a majority of cases a similar trend in aggregation and flotation selectivity (grade at given recovery) was observed. At Louvicourt, improved selectivity with increasing aggregation at pH 10.5 was found. At Agnico-Eagle, an analogous association between aggregation and selectivity was observed at pH 11.5. It is suggested that aggregation influences particle entrainment, the increased effective particle size reducing gangue recovery and hence improving selectivity.

Jan 1, 2004

By Karol Kostúr

This paper briefly describes the current state of underground coal gasification (UCG) processes globally and in the Slovak Republic. Recent results of laboratory and technical tests are presented. In addition, on site measurements have added new knowledge of UCG technology. A series of laboratory tests based on physical models shows promise for managed UCG process control.

Aug 1, 2013

By P. W. Percival, J. J. Janssens

"Whitehorse Copper is a 2600-ton-per-day underground copper mine located within the city limits of Whitehorse, Yukon . In early 1978, due to increasingly difficult ground conditions. it was decided to investigate the conversion from longhole open stoping to vertical crater retreat mining. On-site crater testing by C-I-L demonstrated the feasibility of V.C.R. mining at Whitehorse Copper.After some investigation. a down-the-hole drilling rig was chosen and drilling began in November /978. Blasting began in June /979. and to September 1980 approximately one million tons of ore had been blasted. In-field changes to both drilling and blasting techniques have been implemented. Some of these changes were dictated by problems encountered; others were made to improve efficiencies.To date. V.C.R. mining has proven successful from a drilling and blasting aspect.IntroductionWhitehorse Copper Mines Ltd ., a division of Hudson Bay Mining and Smelting Co., Limited , is a 2600-Lp.d. underground copper mine. The plant site is located I mile west of the Alaska Highway, and approximately 7 miles south of Whitehorse city center. Production is from the Little Chief orebody, and total output is from vertical crater retreat stopes.The Little Chief and Middle Chief orebodies at Whitehorse Copper had original reserves in excess of 6 million tons, most of which graded 2.00/0 copper or higher . The orebodies are typical skarn deposits that have developed along the contact between an intrusive diorite and a limestone-quartzite flank pendant. The limestone has been metasomatized to form a calcium-magnesium skarn which, along the limestone / quartzite contact, has locally further developed into a mineralized magnetite-serpentine skarn. The principal copper minerals are bornite and chalcopyrite, with minor chalcocite and valleriite. Skarn gangue minerals are serpentine, diopside, garnet, epidote, calcite and wollastonite. Appreciable values in gold with some silver are present and recovered as well."

Jan 1, 1981

By Robert B. Parsons

"This article is based on a paper presented by Jim Scott at the 1988 annual convention of the Prospectors and Developers Association of Canada. The paper suggests a number of factors that might be taken into account in negotiating royalty terms.IntroductionRoyal ties are a part of mining life in Canada. They are used by many kinds of individuals in many kind s of situations. Prospectors commonly take royalty interests back when they transfer claims to development companies. Mining companies disposing of undeveloped (or sometimes even developed) properties are often paid at least in part by royalties. Royalties are even used by institutional investors with no other connection with the resource industry.Such different royalty holders have different investment goals, different cash flow requirements, and different risk / return preferences. These differences have given rise to a number of different royalty type s. These types range from the simplest cents-per-ton royalty (where the operator pays a royalty at a fixed rate per ton milled) to net smelter return or ""NSR"" royalties (where the royalty is based on a percentage of the operator's NSR) all the way to net profit interest or ""NPI"" royalties (where the royalty is based on the operator's bottom-line net profit),The fundamental difference between the many royalty types is in the risk/ return relationship. The cents-per-ton royalty, for example, is relatively risk-free. Of the many economic factors which affect a mine, the only one which will affect the royalty holder is the amount of ore physically milled. On the other hand, the potential for significant gains under a cents-per-ton royalty is also very limited. The royalty holder will not share in any increases in the market price of the end product or any cost reductions achieved by the producer."

Jan 1, 1988

By Yasser Mohamed

Daily field management of earthmoving operations requires quick and regular decisions for allocating available equipment to different jobs on a project. A general foreman?s day starts with matching several activities with a suitable set of available equipment to achieve the highest productivity and lowest unit cost. Usually, this decision-making process needs to be quick, and depends to a great extent on the foreman?s experience, which varies from one individual to another. Many analytical solutions with various degrees of sophistication and optimization exist to address such decisions. However, adopting any of these solutions is contingent on how accessible and easy-to-use the solution is. This paper discusses the development process of a webaccessible solution for evaluating earthmoving fleet composition and allocation scenarios. The solution relies on discrete event simulation and an optimization backend engine, but introduces the user with a simplified and easy-to-use interface that is accessible from any mobile device, and is customized to specific user?s needs. The developed system gathers most equipment and site-related input data from a company?s information systems to minimize user input. The user mainly needs to formulate equipment and job combinations and allocation scenarios (e.g. soil type, quantity, and hauling distance), according to equipment availability each day. Then the system will evaluate the productivity and unit cost estimates for each scenario, allowing the user to choose the most suitable one. It may also be used to automatically recommend the optimum solution given an available list of equipment. The paper presents the process followed in prototyping the proposed system in collaboration with a major Canadian earthmoving contractor, and customizing it to the user needs within the company. It also describes the overall structure of the developed system and its core simulation model.

Aug 1, 2013

By Robert B. Parsons

"This article is based on a paper presented by Jim Scott at the 1988 annual convention of the Prospectors and Developers Association of Canada. The paper suggests a number of factors that might be taken into account in negotiating royalty terms.IntroductionRoyal ties are a part of mining life in Canada. They are used by many kinds of individuals in many kind s of situations. Prospectors commonly take royalty interests back when they transfer claims to development companies. Mining companies disposing of undeveloped (or sometimes even developed) properties are often paid at least in part by royalties. Royalties are even used by institutional investors with no other connection with the resource industry.Such different royalty holders have different investment goals, different cash flow requirements, and different risk / return preferences. These differences have given rise to a number of different royalty types. These types range from the simplest cents-per-ton royalty (where the operator pays a royalty at a fixed rate per ton milled) to net smelter return or ""NSR"" royalties (where the royalty is based on a percentage of the operator's NSR) all the way to net profit interest or ""NPI"" royalties (where the royalty is based on the operator's bottom-line net profit),The fundamental difference between the many royalty types is in the risk / return relationship. The cents-per-ton royalty, for example, is relatively risk-free. Of the many economic factors which affect a mine, the only one which will affect the royalty holder is the amount of ore physically milled. On the other hand, the potential for significant gains under a cents-per-ton royalty is also very limited. The royalty holder will not share in any increases in the market price of the end product or any cost reductions achieved by the producer."

Jan 1, 1989

By Judith S. Chan

With the increasing awareness of the need for the reduction of carbon emissions globally, geothermal energy, which offers a potential for cleaner energy generation, is one potential new source. In Alberta, these geothermal resources are likely to be found in the sedimentary basin, or in the deeper crystalline basement rocks. Alberta exhibits a very low geothermal gradient compared to other existing geothermal fields located in areas of volcanic and tectonic activity. To mitigate this effect, the focus in Alberta will involve the development of engineered geothermal systems (EGS) in the target resource. The first goal for EGS research and development is to develop a detailed geological-geophysical characterization of selected sites to delineate potential geothermal reservoirs in Northern Alberta. One of the selected sites is in the Fort McMurray area. The deepest well drilled in the oilsands areas of Northern Alberta is located just west of Fort McMurray. It has a depth of 2363 m and as such can provide details on the physical properties of the rocks, the state of stress, and the existence of fracture porosity toward geothermal investigations. To date, we have acquired temperature logs to study the change in geothermal gradient with depth, and a series of petrophysical logs to study the finer scale structure of the rock formations with vertical resolutions in the range of 0.05 cm to 80 cm. Our aim is to identify geological features such as zones of fractures in the basin and/or basement that could provide an indication of enhanced fluid flow potential ? a necessary component for any geothermal systems to be viable. Zero offset and walkaway vertical seismic profiles (VSP) were also conducted to measure the seismic responses at the borehole. VSP data can be used to delineate the structural and stratigraphic features surrounding the borehole that could not be resolved from surface seismic reflection data that are also available near the borehole. The full integration of well logs, VSP data and surface seismic reflection data are expected to provide a detailed characterization of the sedimentary basin and crystalline basement rocks of the Canadian Shield in Northeastern Alberta and will assist in future planning for drilling.

Jun 1, 2012

By R. E. Phelan

Introduction The Flin Flon deposit was discovered by Tom Creighton, an experienced prospector and trapper, who in 1914 made his headquarters at The Pas, Manitoba, and still lives there. The discovery was made in the fall of 1914, and Creighton and his associates spent the next summer in investigating the find. In August of 1915 the first claims were located. The property was optioned to Hayden Stone & Company, and in the spring of 1916 they started a diamond-drill campaign. Hayden Stone spent $50,000 on the property and, among other things, completed over 7,500 feet of diamond drilling. The ore not being as high grade as expected, and also being complex in character, Hayden Stone then abandoned their option. In the spring of 1917, Messrs. Earle, Faskin and associates took an option on the property and started an extensive drilling campaign. This campaign accomplished approximately 18,000 feet of drilling and secured for the Faskin interests a 32 per cent interest in the property. In 1920, W. B. Thompson and The Mining Corporation of Canada secured an option, and, while this option was in force, sunk two shafts in the ore-zone and did a considerable amount of drifting and cross-cutting in the ore to study the manner in which it occurred in place, and, by actual channel sampling, to check the grade indicated by the previously accomplished diamond drilling. All of this work had indicated that an ore-body existed on the property containing at least 18,000,000 tons of ore, assaying as follows: gold, 0.074 oz./ton; silver, 1.06 oz./ton; copper, 1.71 per cent; and zinc, ). 45 per cent (1). Complete analyses of composites from the drill holes showed that the ore was very complex in character. It contained the above values in gold, silver, copper, and zinc, as well as large amounts of sulphur and iron, and traces of lead, arsenic, antimony, cobalt, and various other metals. Although the ore was obviously pyritic in character, pyritic smelting, the usual method of treating this class of ore, could not be used to beneficiate the ore with any reasonable expectation of making such a venture a financial success, since coke and coal landed at Flin Flon would be expensive, and siliceous flux was known to be scarce locally and low in grade. The property therefore lay idle until 1925.

Jan 1, 1935

By X. F. Liu, O. Buzzi, Y. Sieffert

This study falls in the context of underground coal fires (UCF) where burning coal can elevate the temperature of a rock mass in excess of thousand degrees. The objective of the research was to experimentally investigate the change in mechanical behavior of a rock when subjected to temperatures up to 900 °C. Several blocks of an Australian mudstone were collected from a mining site in New South Wales, Australia. X-ray diffraction and thermal-gravimetric analysis were conducted on powdered rock in order to determine the critical temperatures at which the main mineralogical changes occur. Then, cylindrical specimens were prepared from intact rock blocks for unconfined compression tests. These rock specimens were then treated by heating in a temperature-controlled furnace at temperatures varying from 100 °C to 900 °C. The heating process consisted of two stages: raising temperature with very slow rate of 1 °C per hour followed by a holding period of 24 hours and then a slow cooling process to room temperature. The compression tests were carried out on treated rock specimens to characterize the change in compressive strength. The macroscopical study was complemented by microstructural investigations via optical microscope, scanning electron microscope (SEM) and mercury intrusion porosimetry (MIP). Results show that the unconfined compressive strength of mudstone decreases with increasing heating temperature up to 450 °C, beyond which it increases. This can be explained by the combined effects of micro cracks and mineral thermal reactions caused by heating process.

Jan 1, 2015

By A. Nielsen

"The Polaris mining operation (Fig. I) is located on Little Cornwallis Island in the Canadian Arctic, an area with a very limited shipping season and a hostile climate. The operation consists of the underground works, barge-mounted concentrator facilities, concentrate storage and shipping facilities, a personnel accommodation complex and an airstrip.The electrical energy for the operation is provided by four 2.3 MW diesel-generators installed on the barge. The power is distributed through a 4.16 KV system connected directly to the generators and to the large motors. All other loads are supplied at 600 V or 120 V.The power plant has been designed as a Total Energy System with maximum energy efficiency and thus designed for maximum heat recovery. The waste heat recovered on a year 'round basis is expected to be sufficient for the process heating and drying as well as the space heating for offices and accommodations. The engine cooling system consists of two glycol-water loops, a "" cold"" loop for charge air and lube oil cooling and a ""warm"" loop for jacket water cooling. Each loop is complete with heat exchangers f or heat recovery and out-door forced air radiators to dispose of excess heat. A water loop in the concentrator area transfers the heat from the jacket water loop and the exhaust gas boiler to the space heating equipment, the process and the heating system for the accommodations. Part of the exhaust gas is diverted to the concentrate dryers.IntroductionThe Polaris Mine is a highly mechanized, trackless mine with access through a decline. Drill equipment is electrically powered to minimize fumes and heat. Dry development and production drilling eliminates the need for an underground water supply system.The concentrator, power generators, work shops and auxiliary facilities are located on a barge which is beached in a prepared berth on the shore of Crozier Strait. Oil storage tanks, concentrate storage and accommodation buildings are built on shore. The concentrate storage building ha s a 12-month capacity and is fed from the concentrator by a conveyor system.The accommodation building houses up to 240 people, includes administration office, dining and recreation facilities. The complex is housed in on e interconnected building with public use areas alternating with accommodation units.At full production annual concentrate shipments will amount to about 220,000 wet tonnes. This will be accommodated by about 8 shipments during the regular shipping period-August 15 to October 15. Re-supply of general cargo and fuel will be carried out annually in about 3 shipments within the same period."

Jan 1, 1984

By F. Osmond, R. Kelly

"Malcolm Knowles, the famous adult educator once wrote: ""What a challenge we in human resources development face if we are to avoid the obsolescence of our workforce. I can foresee this challenge requiring that we reconceptualize (...) and redefine the role of HRD, away from that of managing the logistics of conducting training activities to that of managing a system of learning resources"".The context in which this was written surrounds the subject of adult education and the need for business and industry to change its approach to the treatment of adults as learners. In explaining what 'managing a system of learning resources' means, Knowles refers to line supervisors and managers as the most ubiquitous resources for day-in and day-out employee development. In many organizations training has been largely a staff rather than line responsibility. Even where trainers reported to line management, it was still seen as a staff function performed by a few specialists.This change referred to by Knowles places a much heavier responsibility on line supervisors and managers for the development of their personnel than has traditionally been the case. Managing that change - handing over the responsibility to the line organization - is the supreme challenge for the HRD function.Just why is this change necessary? Because too often, the learner does not effectively use on the job what he or she learned in the classroom. In fact, learners often discard new methods and revert to the older ways. The reason training does not stick is that the systems for training and work management are most often separate entities and while one may support the other, they need to be a single integrated system in order to ensure the transfer to the job effectiveness of training and some real value for the training dollars.Because much training can be wasted, steps have to be taken to ensure that it fulfills its intended purpose. The effective and continuing application of knowledge and skills that learners acquire can only be realized when line supervisors and managers are at the centre of the training system.This paper describes how such a systemis being developed at the Iron Ore Company of Canada (IOC) as a functional training program is introduced. The following text provides background information on the IOC - who they are and where they are located, a definition of functional training, an evaluation of the suitability of this approach for adults in industry, a description of how the program is being implemented at IOC and some observations that have been made as this change is experienced."

Jan 1, 1995

By Phil Keele

"Manalta Coal Ltd. 's Vesta Mine will supply Alberta Power Limited's 740 MW Battle River Generating Station with 1 128 000 tonnes of sub-bituminous ""C"" coal in 1983. Mana/ta Coal Ltd. and Alberta Power Limited are in their seventh year of a 31-year coal supply agreement. With the exception of localized topographic highs where three coal seams are mined, the Vesta Mine is primarily a single-seam mining operation. Vesta's comprehensive programs of mine planning, preventative maintenance, reclamation, and employee relations make it an efficient and a well run operation. Introduction The Vesta Mine, located in east-central Alberta approximately 300 km northeast of Calgary, supplies sub-bituminous ""C"" coal to Alberta Power Limited's 740 MW Battle River Generating Station. The coal reserves and principal stripping equipment are owned by Alberta Power Limited. Manalta Coal Ltd. owns and operates the additional mining equipment and support facilities. Coal production is from a single pit, 3.5 km in length. Both single and multi-seam operations are encountered in the active pit. In 1983, production is anticipated to increase to I 128 000 tonnes from 906 000 tonnes in 1982. The additional tonnage will be achieved by operating 24 hours per day, 5 days per week. The following sections briefly highlight historical, geological and mining/reclamation aspects of the Vesta Mine. Figure I illustrates the location of the Vesta Mine in relation to the cities of Calgary and Edmonton. History Coal mining for domestic use began near the turn of the century in the Vesta Mine area. Initially, small underground room-and-pillar operations were dominant. As equipment technology advanced, surface strip mining replaced the underground methods."

Jan 1, 1985

By So-Yeong Lee, Moosang Lee, Seung Hwan Ahn, Ho-Sang Sohn, Jongshin Chang

It is necessary to understand the characteristics, phase changes and chemical reactions of flue dusts introduced from a furnace to an off-gas line in order to achieve the stable operation and the improvement. This study is to develop the dust reaction model for chemical reactions of dusts in an uptake shaft of smelting furnace and a waste heat boiler. Phase equilibria and reaction paths in this system were determined by thermodynamic calculation with experimental and industrial data. The oxidation reaction rate of dusts was determined by the gas film mass transfer controlling. And the sulfation reaction rate was evaluated by the unreacted shrinking core model. Kinetic parameters were estimated by reference data including industrial ones. The present study with the developed model shows various effects of temperatures, dust particle sizes, and O2 gas partial pressures on dust reactions. INTRODUCTION The flue dusts from a copper smelting furnace move along a furnace off-gas stream into an uptake shaft and a waste heat boiler (WHB) and electrostatic precipitator(s). It is necessary to control the dust quality in order to stabilize the operation because the sticking behaviors differ depending on the phase of dusts. Phase changes of dusts are caused by chemical reactions at given conditions such as temperature and partial pressure of gases. Therefore, it is required to understand the phase changes and chemical reactions of dusts in order to perform the improvement and stable operation. The present study carried out the investigation to understand their fundamental knowledge. Especially, this study was focused on the kinetics of chemical reactions of flue dusts, developed the model. In particular, the scope of development and utilization of the model was defined as the uptake shaft of the Mitsubishi S furnace and the S-WHB radiation section in the Onsan smelter. Information needed for the modeling work referred to data from these processes.

Jan 1, 2019

By F. Urekar, R. B. Pankhurst

"Air spaces and air gaps in an explosives column are known to allow greater distribution and cushioning of explosive energy from the rock mass. This energy distribution is enhanced if the explosives ' gases can be confined in the borehole for as long as possible by plugging and stemming above the air space.Power Plug is an inflatable plug which can seal a borehole at any point to separate the stemming from an air gap and explosive toe load.IntroductionThis paper will discussion-going work by C-I -L Inc. and operators of two open pit mines to study the results of using Power Plugs:I. Pit wall stability - the authors have found the Power Plug effective for wall control blasting in open pit mines.2. Selective mining of coal seams - the authors work shows the Power Plug allows mining selective coal seams by predrilling underseam waste wedges.Pit Wall StabilityWall stability in an open pit mine is essential for safety. Good wall stability can be achieved with wall control blasting techniques which cushion the effect s of the explosives charge by decoupling the charges from the borehole wall. The usual method of decoupling a charge in a large-diameter rotary borehole is to load the explosives in tubes (Fig .I) . We now believe the air deck system is effective in sea ling a borehole above the explosive charge to create an air deck within the borehole which will cushion the blast.In a linear decoupled charge, an air annulus surrounds the explosives charge and cushions the effects of detonation genera ted gases on the pit wall. In an air deck, i.e. with the hole plugged at the collar, the gases genera ted by an explosive toe load are sealed in the empty borehole column. After a period of time, these trapped gases produce radial cracking between holes along the entire length of the borehole.It is common practice to employ de coupled explosive charge columns in the borehole to limit blast damage to surrounding rock. The exact mechanism of energy transfer in such blasts, however, is not well understood. Interruption of the continuous explosive column in a borehole by means of stemming, or air decks, may also be viewed as another form of decoupled blast. Decoupling of the explosive charge from the borehole wall affects both explosive energy release and explosion pressure developed in the borehole."

Jan 1, 1988

By René G. del Villar, Jules Thibault, René del Villar

"Some key control variables of industrial processes, associated with product quality, often cannot be measured directly or frequently enough to establish adequate control. In such cases, it is possible to use available measurements to provide a prediction for these process variables and use them in a control strategy, thereby giving rise to what is now commonly called a softsensor.In some industrial grinding circuits, the on-line particle size analyzer is shared between various sampling points. Therefore, for a given location, the actual measurement is only available every 10 to 20 minutes, a delay which is unacceptable for automatic control purposes. To alleviate this problem, a softsensor based on an artificial neural network has been investigated. First, the structure of the neural network and different schemes for the training process are analyzed. Then, the performance of the neural network softsensor is compared with other inferential methods such as ARMA models and Kalman filters.IntroductionGRAHM, French acronym of the Research Group on Computer Applications in the Mineral Industry at Laval University, began in 1990 a research project on Knowledge Based Automatic Control (KBAC). This project, sponsored by a consortium of eight mining companies and the federal and provincial governments, seeked to screen advanced (knowledge-based) methods for data processing (filtering, mass balancing, etc) and automatic control (model-based) for their use in the mineral processing operations and the transfer of the project results to the sponsor companies.In parallel to more academic research work, a number of case-studies have been undertaken with the cooperation of partner companies. Among such works, a very successful one has been the design and installation of a new control strategy for one of the Kidd Creek (Falconbridge Ltd.) grinding circuits. This project was related to the evaluation of a number of control strategies and the implementation of one of them, as selected by the plant management, in the concentrator.A total of sixteen control schemes were evaluated on one of the dynamic phenomenological simulators developed at GRAHM, a trademark of this research group [ l]. The calibration of the simulator models was done based on industrial data gathered by GRAHM and Kidd Creek personnel. Then, the simulator was used to test the performance of various PID-based control schemes, designed to achieve the control objectives set by the Kidd Creek personnel. The best scheme proposed called for controlling the cyclone overflow particle size by manipulating the water addition rate to the cyclone feed box and the circulating load by manipulating the circuit ore feed. The particle size analyzer (PSI-200) available for monitoring the product size, was unfortunately shared (multiplexed) among various streams of the plant, which meant a 14 min delay between two consecutive readings for any particular stream. This induced the plant personnel to choose an alternative control strategy, one which controlled the cyclone feed density instead of the cyclone overflow particle size."

Jan 1, 1996

By E. R. Dixon

Copper SX/EW plants often bleed part of their electrowinning electrolyte to control impurities and maintain consistent cathode quality. Depending on the specific situation at each site, the bleed is either returned to raffinate, to an SX extraction stage, to an SX wash stage, or to the PLS pond, to avoid losing the copper in the bleed. This practice can have undesirable effects on the overall process. An alternative is to electrowin all or most of the copper in the bleed, thus avoiding the recirculation of the copper in the bleed. In this manner, the bleed is converted to metallic copper without interfering with the SX circuit. This in turn reduces the copper concentration in the raffinate, improving global copper recovery because of improved leaching conditions.

Jan 1, 2007

By Friedrich Benthaus

"The natural and man-made realities on either side of the Atlantic are different. Therefore, a large part of the other side' s knowledge and experience cannot be transferred easily. In the following, the author will attempt to describe some of those developments in the German hard coal industry which may be of particular interest to readers on this side of the Atlantic.The area of the Federal Republic is quite small, especially if compared with a country as large as Canada. On a territory the size of the maritime provinces of New Brunswick and Nova Scotia, Germany holds coal reserves roughly corresponding to the total Canadian reserves. More than 20 billion tons of hard coal down to a depth of 1500 m, and more than 30 billion ton s of brown coal of lignite are technically and economically extractable acording to current technology.However, not only are Germany's coal resources more concentrated; the country is also densely populated, and there are dense networks of railroads and highways All components of the so-called infra-structure are available everywhere, be it electricity, any machinery or personnel. Public opinion is likely in favour of an increased utilization of coal.The coal industry is well developed through a long evolution covering centuries. As a consequence, there is an effective and intensive cooperation of numerous bodies and institutions concerned with coal mining, from government agencies including the inspectorate to suppliers, trade union s, producing companies, to jointly operated management and research organizations. In the Federal Republic, hard coal is mined in deep mines only, and lignite in general, only from open-cast pits. There is a complete organizational and geographic separation of hard and brown coal in Germany. Because the Federal Republic holds only insignificant mineral oil and very little natural gas deposits, coal is essentially the only and consequently the most valuable source of energy."

Jan 1, 1984

By D. Lauzon, H. de Ruiter

"In 1988a decision was taken to design and install a computerized mine monitoring and control system. This system had to monitor and control all pumping and ventilation underground. The operation of the mine air heating, using waste heat from the mine water and compressors, was to be part of the system. It ultimately also had to interface with the four existing Canadian General Electric Series 3 PLC's which controlled the No .3 shaft loading pockets. Beside operational control and trouble shooting, the system is a valuable tool in energy management and ultimate savings are estimated at $50,000 per year.The final equipment selection was a General Electric Series Six PLC on surface with a total of 17 Series One Plus and Juniors PLC located underground. Data is transferred through a two-pair shielded cable using modems. Both analog and digital functions are being utilized.The basic monitoring and control system was commissioned during 1989and, due to a higher level of technology today, further improvements have been planned for the future. The system was designed by Walter Dow together with Gordon Champion of D.G. Champion Engineering Ltd. of Toronto. Advice for the ventilation part of the project was obtained from Maurice White, Independent Ventilation Consultant.The Ministry of Energy, Mines and Resources and the Ministry of Energy of Ontario approved this project together with the waste heat recovery project to qualify for a grant of$135,000 under the Enerdemo-Canada program.IntroductionThe Macassa mine is a narrow vein gold mine situated about 2 km west of the town of Kirkland Lake in northeast Ontario. The mine has been in continuous operation since 1933 and a total of about 3.0 million ounces have been recovered out of 6.6 million tons of ore ."

Jan 1, 1991

By R. Grau

"After commissioning and start-up of the first 500m3 TankCell® flotation cell in 2014, the over 300m3 mechanical flotation cells have earned their place in large-scale flotation operations. These 500 to 630m3 cells, designed for projects with large throughputs, are proven to provide savings in project capital and operational expenditure through savings in foot print, energy consumption, and less equipment to install and maintain. Addition to savings in different phases of a project, these cells provides operational flexibility and has shown improvements in metallurgical performance. In this paper a case study from Kevitsa TankCell® e500 installation and Buenavista del Cobre TankCell® e630 installations will be given.INTRODUCTION After development (Grönstrand and Bourke, 2008), characterization (Morales et al. 2009; Yanez et al. 2009; Grönstrand at al. 2009), validation (Elgueta et al. 2009; Coleman and Dixon, 2010), and more than 350 industrial installations of the Outotec TankCell® e300 flotation cell, the well proven energy efficient TankCell® product family introduced the TankCell® e500 forced-air flotation cell late June 2012 (Outotec.com, 2012). The introduction of the 500 m3 flotation cell followed by introduction of a 630 m3 flotation cell, TankCell® e630, in October 2014 (Outotec.com, 2014). These large flotation cells are designed for projects with high throughputs where the number of cells needed for operation with smaller equipment would become large. The benefits of this size of flotation cells comes from the lower capital expenditures due to lower equipment costs, savings in plant footprint, less installation work with less auxiliary equipment, lower energy consumption, and less units per installation resulting in less components, spare parts and maintenance.The first TankCell® e500 was commissioned and taken into operation in October 2014 at FQML Kevitsa Cu-Ni-PGE concentrator, nowadays owned by New Boliden. The first TankCell e630 was taken into operation in January 2018 at GrupoMexico’s Buenavista del Cobre Cu-Mo concentrator. The start-ups of the first TankCell® e500 and TankCell® e630 followed with test work where the hydrodynamic performances of the cells were characterized and metallurgical performance studied. The results of the TankCell® e500 test work were presented in detail by Mattsson et al (2015a; 2015b) and TankCell® e630 by Grau et al. 2018. In this paper the metallurgical improvements achieved with the large cell installations will be presented."

Jan 1, 2019

By Wayne D. Goodfellow, William M. Luff, Steven J. Juras

Brunswick No. 12 is a vent-proximal massive sulfide deposit that formed above a feeder pipe with associated hydrothermal alteration. Because of the replacement of bedded sulfides deposited above the hydrothermal vent, individual sulfide lenses show the following vertical and lateral zoning outward from the vent complex: massive pyrite-pyrrhotite-ehalcopyrite core interlayered pyrite-sphalerite-galena (pb-Zn ore zone) - bedded pyrite. The feeder zone which underlies the Cu-rich core consists of an anastomosing network of pyrite-pyrrhotite-chalcopyritequartz veins with variable and generally minor contents of ferroan carbonate, Fe-rich chlorite, sphalerite, galena and arsenopyrite. Hydrothermal alteration of felsic igneous rocks hosting and adjacent to the feeder pipe is represented by an inner zone (zone I) characterized by sulfide stringers, Fe-rich chlorite, muscovite, quartz, and ferroan carbonate that formed at the expense of feldspars and what was probably glass; outer zones (II and III) are represented by Mg-rich chlorite and muscovite formation, and the albitization and silicification of K-feldspar. Accompanying these alteration trends is a marked decrease of Na + Ca, and an increase in Fe + Mg + C03 in zone I, and increases in Mg + Na in the outer zones. The classic zoning of metals within the sulfide lenses, the formation of a feeder pipe below the vent-proximal sulfide core, and the hydrothermal alteration of felsic volcanic rocks cut by the feeder pipe all support a vent-proximal origin for the Brunswick No. 12 deposit. Furthermore, restriction of sulfide stringer mineralization to the footwall sequence, the folding of the stringer zone by an F, fold, and the difficulty of long distance mass transfer of metals from the sulfides into the host rocks all argue against a tectonic origin for the stringer zone. All of the evidence indicates that the feeder pipe formed during the ore forming hydrothermal event, but has been distorted and in some areas detached from the overlying massive sulfides during subsequent deformation.

Jan 1, 1992