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By D. R. Griffiths

"Oxidation of pyrrhotite prcxiuces sulphuric acid which in turn leaches out heavy metals, resulting in acidic contaminated seepages. The establishment of a marsh on top of the pyrrhotite would result in an anaerobic sediment, which should prevent further oxidation of the pyrrhotite. Initial data indicates that concentrations of sulphates and heavy metals in the seepage water are greatly reduced. Further hydrogeological studies are required however, to determine if metal and acidic loadings to the environment have increased.L'oxidation du sulfure de fer produit de l'acide sulfurique qui a son tour attaque les métaux ayant pour resultat une contamination d'acide et de métal des eaux d'infiltration. L'etablissement d'une couverture faite de boue et de vase au-dessus du depot du sulfure de fer réduit les effets de l'oxidation.Les données initiales indiquent que les concentrations de souffre et de métaux dans les eaux d'infiltration sent grandernent réduites.Des études plus poussées sent nécessaires pour déterminer si les quantités de souffre et de métaux dans les eaux d'infiltration ont augmentées.INTRODUCITONPyrrhotite tailings are readily oxidized through a combination of precipitation and atmospheric oxygen causing acidification of the unsaturated zone above the water table. This reaction is usually catalyzed by the bacteria, Thiobacillus ferooxidans. As the pH decreases, heavy metals become more soluble resulting in contaminated seepages to ground and surface waters.By creating a marshland on top of the pyrrhotite, an anaerobic intermediate layer should form between the organic covering and the tailings, preventing the oxidation process from progressing.In September 1986, Falconbridge Limited implemented a tailing reclamation project that involved creating a marshland on top of pyrrhotite tailings. The following paper will discuss and illustrate the preliminary results obtained during the sampling period of May to September 1987."

Jan 1, 1988

By J. Gogal

Cameco's Cigar Lake Operation (CLO) started commercial uranium ore production in 2015. Initial mining was focused in areas of the ore body with relatively low concentrations of elements of concern (EOCs). As mining progressed into areas of the ore body that were richer in EOCs, some statistically significant behavior of certain analytes was noted in the water treatment circuits. It was ultimately found that the CLO ore body natively hosts numerous alkyl arsine compounds in addition to inorganic arsenide minerals. The alkyl arsines were found to be recalcitrant to typical adsorption on ferrihydrite, with the degree of recalcitrance associated with the degree of alkylation. A number of changes to the process circuits and water balance were performed and planned in order to inhibit the transport of alkyl arsines from the ore stream into the process water stream, and to optimize the overall site water usage. In some instances, the interactions of equipment in conjoined circuits of the process had controlling effects on the behavior of the overall circuit. Work continues to iterate upon the capital design features in order to further tighten the water balance, and to optimize water usage and operating costs.

Jan 1, 2020

By K. Cybulski

Coal dust explosions still remain the main hazard in the coal mining sector, notwithstanding their relatively wide recognition compared to other hazards and the development of effective methods of prevention. Coal dust explosions are still the cause of numerous catastrophes, often leading to fatalities. Fortunately, they rarely occur, and it is for this reason that their hazardous impact is often underestimated. This problem in Poland is being exclusively solved by the Central Mining Institute, Experimental Mine Barbara. Here, basic research on the phenomenon of coal dust explosions and prevention methods is carried out, as well as investigations into the causes and circumstances of past accidents. After 15 years of no coal dust explosion accidents in Poland (1987?2002), a few coal dust explosions have recently occurred, with tragic consequences. These events have taken place not only in hard coal mines, where the presence of dangerous coal dust is the result of common production cycle, and safety measures against coal dust explosions are subject to specific regulations, but also in coal-fired power plants. This is of special concern because prior to 1987, such accidents had been been reported only for coal mines and not for coal-fired power plants. In recent years, two dust explosions occurred in Polish power facilities: the Dolna Odra and Turow power plants. In both cases, coal dust explosions occurred in the fuel supply system, but biomass dust was also involved. The explosions caused significant damage to the systems and buildings. This paper gives description and schematics of the regions of catastrophic coal dust explosions that have occurred in recent years in Poland, as well as the results of post-accident investigations, presenting the coal dust explosion hazard at the accident scene The results specify in detail the state of safety measures against coal dust explosions in light of the relevant regulations in force, including amount of deposited coal dust, content of incombustible matter in coal dust, free moisture content in coal dust, state of coal dust explosion safety zones, and state of explosion barriers. The conclusions from the site inspection and post-accident investigations presented enable us to determine locations of explosion initiation, probable ignition sources, range of explosion flames, and explosion barrier performance. A complete elimination of coal dust explosion hazard at the site of dust deposition is practically impossible to achieve. Similarly, a total elimination of ignition source, which may be related to the occurrence of other natural hazards, equipment malfunction or human errors, is impossible. The examples of tragic events that took place in Polish coal mines and coal-fired power plants highlight shortcomings and mistakes made in terms of assessment and prevention measures taken against the coal dust explosion hazard.

Aug 1, 2013

By K. Reipas

"Westmin Resources Ltd. operates the 3300 TPD H-W underground copper/zinc mine on Vancouver Island. Ore storage underground is handled in a 6000 tonne coarse ore bin and a 3000 tonne fine ore bin. Both of these bins have experienced significant wear since excavation and construction in 1985. Wear problems have included both deteriorating rock walls as well as worn out steel liners and concrete at the discharge points from the bins. Extensive rehabilitation work was completed in 1993.The basis o/this paper is the rehabilitation work done on the coarse ore bin. The design and installation of ground control measures are discussed. The bin access methods used to allow the work to proceed quickly and safely are also presented. This involved the use of a Tekfoam safety bulkhead to protect workers.IntroductionMine DescriptionThe H-W mine was commissioned in 1985. Mine access is by vertical shaft with most production areas at a depth of about 500 m. Host rocks are composed of andesite and rhyolite. Mine capacity of 3300 tonnes per day is achieved mainly by longhole open stoping methods, complemented by room and pillar mining. Metals recovered from the massive sulphide ore are copper, zinc, gold, and silver. Mineable reserves at January I, 1994 were 9.7 million tonnes."

Jan 1, 1995

By Bryon Bisiaux, Walter Valery, Sonny Mwansa, George Amonoo, Adrian Dance

"Newmont Ghana Gold Limited’s Ahafo operation have been working with Metso Process Technology & Innovation (PTI) since early 2009 to increase mill throughput from a combination of controlled blasting practices and optimised primary crusher and grinding circuit conditions. For such Mineto-Mill projects, PTI’s methodology is termed Process Integration & Optimisation (PIO).Ahafo operate a SAG mill, ball mill and pebble crusher (SABC) circuit that processes a range of primary ore of varying hardness from different pits which is blended with soft oxide material. The PTI study focussed on ball mill limited material from the Apensu open pit.Following a benchmarking study of all blasting, crushing and grinding practices in January 2009, PTI recommended changes in both blasting and crushing conditions in order to generate a finer feed size to the SAG mill. Additional operating changes in the grinding circuit were recommended.A series of trials were conducted in November 2009 where three blasts were fired using a different blast design (hole diameter and explosive type) in the same area of the Apensu pit as the benchmarked material in January 2009. Top and bottom benches (or flitches) from each blast were sent exclusively to the grinding circuit and the material was tracked using PTI’s SmartTag™ system.The results from the six trials showed a significant increase in primary ore throughput at a reduced blend of oxide material. Ahafo have since standardised on these modified blasting conditions for all Apensu ore zones and have been able to sustain higher throughput compared to historical performance on similar material.This paper summarises the phases of the PIO project, the changes made in operating practices and the outcomes of the blasting trials that validated the predicted increase in mill throughput."

Jan 1, 2012

By Zhiye Zhao, Jianping Sun, Zhipeng Xu

"The subsea rock cavern project is an underground storage facility. For cost-effective and safe excavation, the risk caused by the groundwater seepage into the rock cavern must be addressed. As one of the essential steps of the assessment work, the hydraulic conductivities of the fractured rock masses should be reliably determined based on the limited measured data and geological information from the few boreholes. On the basis of site investigation data and monitored water flow and water pressure data during excavation, this paper presents an estimation method for hydraulic conductivities of the rock masses containing water bearing zones.INTRODUCTIONIn the development of underground rock caverns/tunnels, the uncertainty of hydro-geological conditions plays a critical role in terms of construction cost and construction safety. Excessive groundwater seepage has been identified as one of the key safety factors which always lead to vast loss, such as the Seikan Tunnel in Japan which encountered sudden water inflow and then catastrophic face collapsing, tunnel flood during excavation (Xu et al., 2013). As a key factor in the risk management associated with the groundwater leakage into rock cavern, the hydraulic conductivity determination is very important for cost estimation, reliable water control and construction management.The case presented in this paper is an underground project consisted of a cluster of rock caverns/tunnels for storage of hydrocarbon products. These caverns are located in heterogeneous sedimentary bedrock, at a depth of 130 m beneath a basin, and the crowns of caverns are located at about 100 m below the sea bottom. The caverns/tunnels are designed at two levels, the water curtain tunnels are at the upper level, and oil storage caverns are at the lower level, as shown in Figure 1. A number of horizontal and vertical water injection holes drilled from the upper water curtain gallery tunnel will establish continuous horizontal and vertical water curtains for providing a stable pressure distribution around the caverns, to keep oil/gas inside the lower storage caverns. As the hydrostatic pressure of groundwater around the storage caverns is higher than the pressure of stored oil and gas, the stored oil and gas will not leak out of the cavern (Lu, 2010; Xu et al., 2015). Groundwater pressure gauges are installed in the water curtain gallery tunnels, and water from the operational and access tunnels is injected continuously into the curtains to maintain the pressure. Some monitoring data are recorded at different construction stages. This paper proposes suitable methods to predict the hydraulic conductivity in rock mass and to determine the hydraulic conductivity in the water bearing zones."

Jan 1, 2015

By C. Chapman, P. Cowx

"INTRODUCTIONTetronics Research and Development Co. Limited has installed several plasma torches for steel heating in continuous caster tundishes. An extensive demonstration program on a 14 tonne tundish reported the following advantages of plasma heating.• close control of steel temperature to ± 5°C;• a reduction of the furnace tapping temperature of up to 20ºC, leading to savings in energy and refractories costs ;• improvement in steel quality, to produce a slab product with an equi-axed crystal structure and a reduced number of large sub-surface slag inclusions;• the virtual elimination of oxygen pickup in the tundish; and• the capability of making ferroalloy trim additions to the tundish to permit a change of steel grade during casting, greatly decreasing inventory costs.The Need for Tundish HeatingIn the continuous casting of steel, the function of the tundish is to transfer the molten metal between the ladle to one or more continuously fed casting moulds. Figure I shows a typical temperature profile of molten steel in the tundish over the first cast cycle. It is observed that a rapid drop in temperature occurs both at the start of the cast, due to the tundish refractories absorbing heat, and also during ladle changeover. In addition, as a result of thermal losses through the ladle sidewalls, there is a gradual decline in the bulk steel temperature over the entire heat cycle. Consequently, in normal tundish operation, it is necessary to cast with a high superheat (25°C to 30°C + above steel liquidus temperature) in order to prevent freeze-up of the strand. Problems of high temperature variation and the potential of the steel solidifying in the tundish are greater for small caster units of low thermal mass . A high steel superheat increases the steelmaking vessel process time and refractory wear and prevents the formation of a uniform equi-axed solidification structure in the cast steel, resulting in centre line segregation and porosity. The large drop in the casting temperature that occurs during unsteady state operation causes an increase in the number of sub-surface inclusions, reducing the value of the product. Accordingly, plasma heating may be employed to maintain the molten steel at an optimum temperature to produce a slab of consistent quality."

Jan 1, 1989

By W. R. Richmond, T. S. Li, D. Ilievski

The reactive precipitation of ferrihydrite was studied in a laboratory semi-batch precipitator, where a highly concentrated sodium hydroxide solution was fed into an iron nitrate solution. Instantaneous hydrolysis of iron[III] takes place when the two reagents are mixed generating supersaturation, and leading to immediate precipitation of ferrihydrite via a primary nucleation mechanism then followed by limited crystallite growth to 3 to 7nm. A mathematical model of the semi-batch laboratory precipitator was used to simulate the pH responses during the precipitation of ferrihydrite at different reagent feed rates. The model comprised of interconnected compartments of averaged hydrodynamic conditions, incorporating physically meaningful turbulent mixing time constants. The precipitation process is described by the solute concentration conservation equation incorporating a postulated ferrihydrite primary nucleation model. It was found that the semi-batch precipitator model predicted the experimental pH response reasonably well. The experimental results demonstrated that the reagent feed rate has a critical effect on the course of the precipitation of ferrihydrite, i.e. it is a rate determining step given the fast hydrolysis and precipitation kinetics.

Jan 1, 2005

By Deepak Bhadouriya, Saurabh Singh, Aditya Raj Suman

"An experimental study of chemically enhanced filtration and dewatering of fine coal slurry with and without additives was carried out. The experiment involved determination of effect of slurry concentration, additives (cationic, anionic and nonionic), filter area, filtration velocity, particle size and cake resistance on dewatering and filtration using vacuum filtration cell. Finally, the rate of filtration and dewatering and optimum amount of additives used were determined under suitable filtration condition. Overall, it was found that the filtration and dewatering characteristics were enhanced by increased slurry concentration, larger filter area and larger particle size. In addition of additives, the kerosene was found to be best for enhancing the filtration which yielded cake moisture reductions of approximately 17% by weight. At optimum dosages, the final cake moisture contents were reduced by 3.6% and 5.8% by weight using the appropriate surfactant and flocculent, respectively.INTRODUCTIONFor India, it is estimated that coal constitute a principal source of energy for the next several decades. It is majorly used at thermal power plants to generate electricity and also to a great extent in steel and cement industry. It has been observed that its consumption is increasing so as to meet the energy requirements of the country. It has been found that in a coal preparation plant; approximately 20-25 percent coal is of the mined coal of the range below minus 0.5 mm (28 meshes). Generally, this fine fraction is discarded due to its high cost of processing and further utilisatisation is very minimal. But with ongoing research and development for advanced clean coal technology, various new techniques have been evolved to maximize the utilization of available coal. In recent time technologies such as column flotation, cleaning of fine size coal to lower the ash content and low pyretic sulfur is feasible at high recovery value. But in various researches it is found that one of the biggest hurdles in utilization of fine coal cleaning technology by the coal industry is the economic dewatering of the fine clean coal product. Thus, until an economical and practical solution to dewatering of fine clean coal is achieved, the efforts devoted to developing fine clean coal technology will be wasted. In this paper an effort toward enhancing and developing the optimum technique of dewatering and filtration of fine coal slurry has been made."

Jan 1, 2016

By H. Salamanca

Recently, the mining industry has become one of the leading target markets for the technology industry as they need to innovate in their productive processes in order to boost productivity, reduce operation costs, increase operation safety, and improve the quality of life of their workers. This work presents the technological developments that HighService has done in different stages of the mining productive processes to include robotic manipulators in their automation solutions as well as the development of new equipment and sensors. The robotic technology integration is presented in different applications such as handling and selection of cathodes in E-W machines, automation of base plate maintenance, automation of cathode stripping machine, and multi-tools handler for liner bolt replacement in SAG mill liner maintenance activities. The proposed solutions show technical and economical viability with low initial investment and short implementation period of six (6) to ten (10) months. The results have been validated in plant, obtaining higher production rates and availability.

Jan 1, 2007

By Madaah Hosseini H. R., P. Abachi, S. Miraghaei

In this study, the effects of milling time, chemical composition and heat treatment on microstructure and magnetic properties of nanocrystalline Fe-Si (6.5-25 at.% Si) alloys prepared by mechanical alloying have been investigated. The results show that increasing the milling time or the Si content, decreases the lattice parameter and increases the internal microstrain. The prepared powders mainly consist of micron-sized particles with an average grain size of less than 20 nm. The specific saturation magnetization values are slightly less than those of single crystal or conventional Fe-Si alloys and decrease as Si content increases. The coercive force values of the nanocrystalline as-milled powders are much higher than those of corresponding Fe-Si bulk alloys with a minimum at 13.5 at.% Si. The values of coercive force decreased after annealing but it seams that the residual strain developed during milling is not the major contributing factor to the higher values of coercive force in the mechanically alloyed powders and nanocrystals behave as single-domain particles without exchange interaction between them.

Jan 1, 2006

By J. Pontt

Gearless mill drives (GMD) offer high performance for torque and speed control for grinding mills and have been applied successfully in modern concentrators for wet grinding with mill diameters from 34 to 40-feet. It is considered a mature technology. However, recently, some large GMD?s have presented unexpected failures in stator and rotor subsystems. The phenomena involved in such failures has shown a complex nature and surprised users and manufacturers. The manifestation of such failures has been observed as mechanical damages to certain components of ring motors. This paper presents a discussion on the electromagnetic forces that can generate stresses in the electrical ring motor that can produce failures and outages. Guidelines for further research and contributions to improved reliability of GMD?s are proposed.

Jan 1, 2012

By H. Arima

The Akita Zinc Company is the only refinery which produces hematite from the iron content in the zinc leach residue. The Akita Hematite Process consists of five stages, which are SO2 pressure leaching, the first neutralization stage, the de-arsenic process, the second neutralization stage and pressure hematite precipitation. In order to strengthen its cost competitiveness and stabilize its operation, the Akita Hematite Process has been modified continuously. Most recently, two process modifications were carried out. The first was an improved ability to maintain a lower arsenic concentration in the de-arsenic process, and the second was an increased throughput in the hematite precipitation autoclave. The details of these recent changes in the Akita Hematite Process are presented in this paper.

Jan 1, 2006

By Bert Taylor

"The Mining concessions of Quemont Mining Corporation, Limited, are located at 48°16'N latitude, 79°00'W longitude, in Rouyn township, northwestern Quebec. Six hundred and forty acres in area, they lie directly north of, and contiguous to, the Horne mine of Noranda Mines Limited. The north arm of Osisko Lake covers a large area of the southern part of the property. The orebodies lie below the Jake with one body extending through to the bedrock surface.The property was staked in 1922, and was originally known as the Murray Claims. The group attracted interest from numerous exploration companies because of the proximity of the Noranda orebodies.The United Verde Extension Company, of Arizona, optioned the claims in 1926. They sank a shaft to a depth of 235 feet, at a short distance from the Noranda boundary. From a level established at a depth of 215 feet they completed 3000 feet of exploratory driving from which 6000 feet of diamond drilling was done. Only a small body of siliceous gold ore was found before they dropped their ·option.In 1928, The Mining Corporation of Canada purchased a 90 per cent interest in the property. An operating company, later named Quemont Mining Corporation, was formed. An electrical survey was carried out on a portion of the property, followed by deepening of the shaft to 922 feet. Levels were established at 500 and 900 feet, and 4,800 feet of driving and more than 3000 feet of diamond drilling were carried out from them.Geological knowledge at that time recognized that a major break, the Horne Creek fault, lay not far inside the south boundary. Striking north 80 degrees east, the fault dipped south at 85 degrees. The rock on the north side of the fault was massive rhyolite; to the south, meta-diabase and a little rhyolite. A left-handed movement was indicated by a 600-foot offset on a north striking diabase dyke. The small body of siliceous gold ore, referred to previously, was confined to the 215 level."

Jan 1, 1949

By Geo. E. Cole

A GREAT deal of time and energy is now being devoted to the study of post-war reconstruction and rehabilitation, in spite of the fact that as yet we have not won the war in which we are presently engaged. If you feel that the study of post-war problems takes our thought away from the problem immediately before us, you may well query, "Well! What has all that to do with winning the war, our most urgent problem today?" The answer has been given by Principal James of McGill University, Chairman of the Cabinet Committee on Reconstruction: "Reconstruction is something which must be thought of in advance, partly for the purpose of recognizing exactly the influence of war-time activities, controls, and regulations on the post-war Canadian scene. Many people are acutely interested in this great problem. It is not that they are not interested in the war itself, or epochal events that are taking place from day to day. They have a vision of that future which they hope will be Canada's, and this vision inspires them to even greater efforts at the present time". The trend of events would indicate that changes, economic and industrial, after this war will be greatly out of line with those that followed previous wars in history, for the present struggle has involved every nation in the world. In the peace that will come, every engineer will have a task in bringing the most desirable order out of the most distressing chaos. We certainly are living in a changing world; we are witnessing geo-graphical and economic readjustments that no other generation in world's history has ever witnessed. And there is an opinion gaining strength in our Dominion, as in other lands, that after this war we shall live in a world in which our process of thinking and our very way of life will have to undergo drastic changes to cope with the new order of things. Sadly our world of today has had to revise the sublime vision that nation shall not lift up sword against nation, while salvage operations continue to beat ploughshares into tanks and the peaceful pruning-hook into a weapon for the deviltry of the commando.

Jan 1, 1943

By Robert A. Brown

"The O'Brien mine is in the west-central part of Cadillac township along the Cadillac 'break', which extends for 7,500 feet from west to east across the property.The ground was staked in 1924 by A. Dumont and W. Hermeston, prospecting for M. J. O'Brien, Limited. The first vein discovered is that now known as No. 1. The No. 4 vein was later exposed on the surface; the other veins known to be present were revealed by underground work and diamond drilling carried out both from the surface and underground.The mine is developed from three vertical shafts: No .. 2 extending from the surface to 2,000 feet; No. 3 from the surface to 1,500 feet; and No. 4 from 2,000 to 3,000 feet. There is on the property a mill of about 200 tons a day capacity, the usual shops, and a townsite housing about forty-five families. Gold production to the end of September, 1944, amounted to 295,824 fine oz. from ore having an average grade of 0.505 oz. a ton. In addition, the mill recovered 3,237 tons of arsenic trioxide having a purity of 83 per cent As2O3.GENERAL GEOLOGYThe four main groups of rocks of the Cadillac area- the Cadillac, Blake River, Kewagama or Pontiac, and Malartic- are found within the boundaries of the property. However, as these rocks have been fully described in · various government reports (1,2,3,4,5,6) and all the known orebodies occur within one group- the Blake River-a detailed description of the geology will be dispensed with here. The known ore deposits lie south of the Cadillac 'break' in a group of rocks that includes 'greenstones', greywackes, conglomerate, porphyries, and a rock of gabbroic composition that may be intrusive. Both flows and tuffs can be recognized in the 'greenstones'. The two bands of porphyry that trend easterly across most of the property have been considered by some observers to be dyke rocks and by others to be flows. Certain evidence points to their being dykes that were intruded as sills considerably prior to the emplacement of the gold-bearing veins, but the possibility of flow origin cannot be fully rejected. North of the talc-chlorite-carbonate schist zone forming the 'break' the rocks are conglomerate and greywacke with iron formation, in which there are no known veins of ore grade. Within the schist zone are minor acid and basic intrusives. The general trend of both bedding and schistosity is a few degrees south of east. The dip is generally vertica1 or steep to the south."

Jan 1, 1954

By D. H. Wilson

"This paper examines the increasing need for mechanical-electrical people within the industry and some of the reasons why such a shortfall exists. It is suggested that, in part, it is image related. The present industry-education relationship in addressing the situation is examined and some thoughts are expressed on how these may be built on, in order to help solve the problem of attracting people to this critical area.IntroductionAs a long-time proponent of plant engineering and maintenance as a management function, I would like to review the progress made by the industry/ educational approaches in satisfying the needs in that area. In doing so, I would like to make the following points:1) that there has been an accelerating shortfall of mechanical-electrical people relative to the needs of the industry;2) that the condition will probably get worse before it gets better; ,3) that the past industry I educational approaches to alleviate the problem have met with limited success; and finally4) I would like to review some of the things being done and consider how these efforts might be extended."

Jan 1, 1981

By R. Drozd

"The Bullmoose Mine is currently under construction in the North East Coal area of British Columbia, and approximately $300 million will be spent to bring this 2.3 million-tonnes-per-year metallurgical and thermal coal mine into production by December 1, 1983.The project is an unincorporated joint venture undertaking, with Teck-Bullmoose Coal Inc., a wholly-owned subsidiary of Teck Corporation, holding 51%, Lornex Mining Corporation holding 39%, and Nissho-Iwai (Canada) Ltd. holding 10%. Bullmoose Operating Corporation will be the manager and operator of the project.This paper will broadly cover the history and exploration work on the property, the geology, open-pit mining plans and equipment, the preparation plant flowsheet from breaker station to clean coal silo, the 35 km highway truck haul, the railroad loadout system, manpower requirements, construction progress, approvals and permits, and general financial arrangements.IntroductionThe Bullmoose Mine Project"" is located about 87 road kilometres south of Chetwynd, B.C. and consists of an open-pit coal mine, a plant facility in the Bullmoose Creek valley below the mine, and a separate rail loadout facility on the British Columbia Railway Branchline near the new town of Tumbler Ridge some 35 road km to the east.The plant will be capable of producing a total of 2.3 million tonnes per year (mty) of washed metallurgical and thermal coal. Long-term metallurgical coal contracts for high quality, medium volatile, bituminous coal have been signed with nine Japanese buyers for 1.7 mty, and the balance of 0.6 mty will be thermal coal production.Plant construction began in the spring of 1982, and in May 1983, preproduction waste and overburden removal in the mine will commence. The plant should be fully operational by December 1983, and first vessel loading at the Ridley Island port is scheduled for January 1984."

Jan 1, 1983

By A S. Leitch

This paper is based on the accident prevention pro-gram carried out in the coal mines of Alberta. It defines the role of the Alberta Mines Branch and of The Work-men's Compensation Board, and relates how a safety pro-gram was initiated. The formation of the Alberta Class 1 Mining Safety Council is also described. The responsibilities of both management and the individual worker are then outlined, and the main features of a successful accident prevention program are delineated. T HE purpose of this paper is not to repeat generalities and platitudes about industrial safety, but rather to relate the experience of Alberta coal mines during the past number of years in their efforts to keep accidents to a minimum. It has been learned from experience that many basic principles are as sound today as they were 20 years ago. How-ever the complexities of modern mining methods and the modern man or miner have created problems that did not exist then.

Jan 1, 1964

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