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By Rhual L. Guerguerian

MINING has been practised by mankind for over sixty centuries (1). In 1876, the "ball mill" was patented, and during the century that followed rotary grinding developed to the state where individual machines are treating tens of thousands of tons of ore per day. This paper gives a brief description of design practices prior to the availability of advanced facilities, followed by modern analytical design development at Dominion over the past ten years.

Jan 1, 1978

By M. Grenon

"The presence, size, orientation, nature, and persistence of geological discontinuities dictate the behaviour of a rock mass. Block size, which is defined by discontinuity spacing, by the number of joint sets, and by the persistence of the discontinuities delineating potential blocks is an important indicator of the degree of fracturing of a rock mass. Consequently, block size is represented either explicitly or implicitly in all rock mass classification systems employed for analysis and design of surface and underground mining structures. Insitu block size distributions may provide a better means to describe the structural complexity of a rock mass. These are the distributions that would be derived if the in-situ rock mass was separated into its constitutive blocks, delineated by existing discontinuities, and each block measured. This paper presents the results of a field campaign at Louvicourt Mine aiming to characterize the rock mass using different methods for determining block size and block size distributions. IntroductionGeological structural data are used to provide input data for analysis and design methods for surface and underground structures. As the collection of structural data involves considerable investment of time and effort, it is sometimes overlooked, thus denying an important source of information for mine design. What is somewhat surprising, however, is that when structural data are available, they are not used to their full potential. Recent work has shown that data on block size have potential applications in different areas of rock engineering:• Blasting — Hudson (1993) has described the excavation process as the change of a preexisting natural block size distribution to the debris fragment size distribution (Fig. 1). Lizotte and Scoble (1994) have reviewed previous efforts on integrating site specific geological conditions into blast design. Grenon et al. (1997) provide a case study where in-situ block size distributions are compared to photogrammetric studies of blasted rock.• Rock mass classifications — Block size is used in the majority of rock mass classification systems either explicitly, as in the RMi classification system Palmstrøm (1995), or implicitly, such as in the NGI system, Barton et al. (1974)."

Jan 1, 1998

By C. M. Campbell

THE dire effects of rapidly vanishing natural resources, widespread unemployment, and increased debt and taxation in recent years have challenged Canadians to produce a practical solution to these national economic problems. In more recent months, wars and rumours of war have indicated, among other things, the need for better control of our mineral wealth. The erection of a smelter on the lower mainland coast of British Columbia, treating all Western ores, and such ores as it will be found advisable to import, will make an important contribution toward a solution of these problems. It is believed that the ores tributary justify a smelter of major proportions. A stock-taking to confirm this can be made with reason-able accuracy in a short time, and this should be undertaken without delay. Enough general information is, however, available .in this paper to justify the technicians of the Department of Mines at Ottawa and of interested smelting companies making a preliminary study of the matter. THE DEFENCE ARGUMENT As a factor in rearmament, metals play a vital part. That rearmament is to continue on an increasing scale is indicated in Premier Chamberlain's address of October 3rd last, when he said: ?'For a long period now we have been engaged in this country in a great programme of rearmament which is daily increasing in pace and volume. let no one think because we have signed 'this agreement between the four powers at Munich we can afford to relax our efforts or call a halt in our armaments at this moment'. As matters stand, the facilities in British Columbia are entirely out of line with the strategic importance of this Province as the Western Front of Canada and the Empire. All our copper ores, and an appreciable part of our lead and zinc ores, are sent for treatment to Japan, United States, and Europe, while we import our iron and alloys. A treatment plant on this Coast would not only give us control of war metals and chemicals but it would provide an increased industrial and research population, badly needed in this area and of the greatest value in the case of war. This is where the mining industry can do its bit.

Jan 1, 1939

By E. Gaucher, D. C. Gagnon

"The paper refers to methods and concepts used in the computer treatment of banks of geophysical, geochemical and geological data, relating to the exploration of massive sulphides. In particular, a data bank of 400 drill holes on independent conductors can be used to calculate probability levels of intersecting a certain quantity of sulphides according to the characteristics of the conductor. Inversely one can, using the data bank and some cost assumptions, simulate and optimize the cost of intersecting a certain quantity of sulphides by selecting drill targets among conductors according to conductivity, magnetism or gravity. Problems of noise, inherent in any simulation, are illustrated in this paper by the results of a study of the nomenclature of volcanic rocks of 27 drill holes by forty geologists. Compilations of data banks are long and timeconsuming, and it would help to standardize to allow exchange of data. We believe that such efforts may result in the discovery of more mineral deposits and at a lower cost. The present study is supported jointly by SOQUEM The New Jersey Zinc Co. and Cominco Ltd."

Jan 1, 1973

By C. R. Kato, G. Proulx

"Within the continuous scenario of reduced aluminium price and plants production costs increase, the energy consumption optimization in the aluminum electrolytic pots continues as the main focus for the producers. Energy consumption was chosen as a key performance indicator to drive the efforts and actions for improvements. Alcoa improved the energy consumption by approximately 3% from 2005 to 2015. This improvement was a result of best practices implementation, new technologies introduction, strategic actions with plant curtailments and management practices. The main objective of this paper is to highlight the importance of the management practices for planning and operational improvements beyond the technology changes. About 10 years ago, Alcoa reorganized its approach to retain knowledge in the Smelters by using a Best Practices format. For each specific subject, a skilled team defined the minimum requirements and the Best Practices for several aspects of operation and maintenance, which affect the environment, safety, cost, customers and performance. These Best Practices were deployed to all Smelters combined with training sessions to process and operation professionals. We will describe how the Best Practices were organized, the deployment strategy used, and the approach to measure the plants’ success. We will describe the management approach that includes Manufacturing Analyses focused on 3-year potential, annual planning, and weekly monitoring of plant stability. A manufacturing analysis is organized at select plants with cross-functional participation of specialists from technical, operational, procurement and finance. The output of a manufacturing analysis includes a roadmap of enablers to improve energy efficiency. A quarterly follow-up of enabler deployment is held with the plant and resources that participated in the analysis. Annually, there is a Planning Process where energy consumption enablers are selected to be implemented during the next 3 years for each plant. A monthly critical analysis is made by the plants with regional best practice support. On a weekly basis, key performance indicators are reviewed with determination of a stability index for each plant. Any deviation signal of unstable condition is alerted and supporting resources are diverted to the plant to reverse trend with countermeasures.INTRODUCTIONDue to factors like excess aluminum in the market and lower consumption in China, the LME price is declining along the last years, as showed in Figure 1. In 2011, the price peaked at US$ 2,400/ton and since then, continues to trend down and approaching the lowest level at US$ 1,500/ton in the last 5 years."

Jan 1, 2016

By J. Kolacz

"A new sensor based sorting system has been developed, providing a possibility for laboratory scale testing and further scale-up of the separation results to the industrial operation. The new system contains different sensors as: X-ray detectors, visible light cameras, NIR cameras, ultraviolet cameras and magnetic sensors, in the same sorting unit. The sorting unit allows advanced calibration options and fine-tuning of the installed sensors to achieve the best separation effect under controlled conditions. Finally, the processed material can be analysed and separated by the rejection mechanism, similarly to the industrial scale operation. At the same time, the process is carried out with limited amount of material allowing detailed statistical calculations for processed particles and all sensor types. The optimal settings and sensor types are specified for the industrial application.The paper describes the scale up of the results achieved for iron ore and coal, where the test work was first carried out using the new laboratory sorting system and where the industrial scale sorting system has been built, in the final stage. The industrial scale sorting results showed a very good correlation between the laboratory and full scale operation. Thanks to the detailed study carried out in the laboratory equipment, the settings of the sensors in the full scale operation provided much better separation efficiency. It was especially important to provide proper setting for the X-ray sensor data calculations, which can be very critical for achieving the best results. During the industrial scale sorting of coal, the input material had 40-55% rock particles as the direct source of ash in the coal stream. The optimal laboratory unit settings and transferring these settings to the industrial sorter, provided 98.8% efficiency for removing rock particles with only few % losses of coal."

Jan 1, 2016

By N. J. Bunce, B. Vollick, A. F. Souza, D. Bejan, P. Maharaj, C. Shamshoom

"Copper electrodeposition from synthetic and authentic acid mine drainage (AMD) is inhibited by ferric iron (Fe(III)), through re-oxidation of copper. Polarization to –2.5 V versus standard hydrogen electrode prevents the dissolution of predeposited copper from the cathode. Above pH 1, copper deposition is independent of Fe(III) concentration to approximately 25 g/L. Fe(III) is reduced to ferrous iron (Fe(II)), with a high combined current efficiency for iron and copper reduction. In a divided cell, the conversion of Fe(III) to Fe(II) is almost quantitative, with efficient transfer of acidity from catholyte to anolyte. Prospects for developing electrochemical technology for complete remediation of AMD are discussed.RÉSUMÉ En raison de la réoxydation du cuivre, le fer ferrique (Fe(III)) nuit à l’électrodéposition du cuivre à partir de drainage minier acide (DMA) véritable et synthétique. Une polarisation à -2,5 V par rapport à l’électrode standard d’hydrogène empêche la dissolution du cuivre déjà déposé de la cathode. À un pH supérieur à 1, la déposition du cuivre est indépendante de la concentration en Fe(III) jusqu’à environ 25 g/L. Le fer ferrique est réduit en fer ferreux (Fe(II)) avec une efficacité combinée élevée pour la réduction du fer et du cuivre. Dans une cellule divisée, la conversion de Fe(III) en Fe(II) est près de la quantité théorique, avec un transfert efficient de l’acidité de catholyte à anolyte. Les perspectives de développement d’une technologie électrochimique pour la remédiation complète du DMA sont discutées."

Jan 1, 2016

By J. M. Livingstone

"This paper covers some of the problems confronted by Canada's railways in moving bulk materials from their source to the dock-site. The ""cost center"" concept is presented, and hypothetical examples of its use given. Also discussed are systems design, the unit train and pipelines.INTRODUCTIONCANADA LIVES BY RER EXPORTS and the Port of Vancouver by the exports of the Mountain and Prairie Empire at her back. The most recent estimates of off-shore shipments of bulk from the Port of Vancouver rise to 35.8 million shipping tons in 1985 and deep-sea general cargo estimates, in and out, are estimated at 7.6 million shipping tons for the same year. This compares to 7.67 and 2.87 million shipping tons, respectively, in 1965."

Jan 1, 1968

By MAX VOS

Lithium is the lightest and electrochemically most reactive of all metals. Renewed interest in lithium coincides with research in lithium batteries and power generation by atomic fusion. Ontario lithium resources are contained in spodumene pegmatites that can form where medium- to high-grade metamorphic volcanic-sedimentary formations are intruded by pegmatite and porphyritic granitic rocks. Spodumene pegmatites occur in at least twelve locales throughout northern Ontario, all of which are in the Superior Province of the Precambrian Shield. Tantalum, cesium, rubidium, beryllium, niobium and tin also were noted with lithium in spodumene pegmatites. Considerable potential remains for discovery of additional lithium and rare-element pegmatites in northern Ontario.

Jan 1, 1984

By M. L. Trépanier

"Engineering and technical services are supplied by the Engineering Department, located at Thetford Mines, Quebec, approximately 60 miles southwest of Quebec City. The department serves the three operating mines in the Thetford area, the Asbestos Hill mine at Putuniq, Nouveau Quebec, and the Nordenham plant at Nordenham, West Germany. The Engineering Department is responsible for supplying the following services. 1. Administration and coordination of capital projects. 2. Engineering, design and drafting services for in-plant changes or improvements. 3. Preparation of geological plans for mine planning and ore reserves determinations. 4. Short-, medium- and long-term mining plans. 5. Rock mechanics studies and monitoring. 6. Grade control monitoring. 7. Environmental control engineering and construction. Details of the organization and services rendered will be the basis of the paper."

Jan 1, 1976

By M. Somppi, D. Weirmeir, Z. Yamak

"Milling operations commonly employ activated carbon to capture complexed gold from lixiviants in leaching processes. As the carbon moves through pipes, pumps, vessels, kilns and other processes in the gold leaching circuit, this consumable may experience losses by various mechanisms like attrition, breakage, and rupturing. Whenever possible, capturing the fine gold-bearing carbon portion of this stream could provide value to milling operations at low capital cost and manageable financial risk. Identifying, testing, and validating the successful payback of a low-tech flocculant system is described. However, the work more closely explores a Monte Carlo risk-based methodology for understanding the potential payback of this project at various confidence levels – an approach that many improvement projects can follow where some level of uncertainty exists.INTRODUCTION Gold milling operations commonly employ activated carbon to adsorb gold from solutions. Normal handling causes the carbon particles from this material to abrade, break, rupture to a size that becomes too small for further use in the process. Operations often concentrate on capturing the fine particles because gold is associated with the carbon and this metal content can be a valuable revenue stream for toll processing. However, the small particle sizes become difficult to separate from the process and can ultimately leave the facility in the waste stream. Hence, operations often place a great deal of care in capturing as much fine carbon as possible by a variety of methods including using screens, settling tanks, and chemical methods. Retrofitting a circuit to capture more carbon fines is common but can expose the operation to financial risk. Approaching this potential improvement by leveraging a Monte Carlo methodology can be effective in understanding the risk and the associated payback of a project at various confidence levels. This method provides a strong framework for capital go-no-go decisions and the structure to validate the potential project success before implementation."

Jan 1, 2019

By Randy Settgast, Daniel Moos, Hyunil Jo, Ghazal Izadi, Christine Baba

"Analyses of production logs of multiply fractured horizontal wells in unconventional plays show that only a small percent (~30%) of perforation clusters contribute to production. We present in this paper one possible approach to mitigating this problem, based on use of a fully 3-D numerical model of fracture propagation through a heterogeneous medium, by studying the influence both of spacing and of perforation friction on the initiation and propagation of simultaneous hydraulic fractures from a horizontal wellbore. The results indicate that while limited-entry perforating can help to equalize the lengths of fractures simultaneously growing from multiple clusters, it cannot equalize their widths. Both fracture width and fracture length can be equilibrated by combining non-even cluster spacing with limited-entry perforating. This has obvious benefits as it allows equalized placement of proppant across the entire series of perforation clusters, resulting in similar fracture widths and conductivities which enhances the likelihood that all clusters will contribute equally to production.INTRODUCTIONThere is substantial evidence from production logs and other information that during the hydraulic stimulation of horizontal wells, not all perforation clusters within a given stage will produce. One possible cause is the interaction between the hydraulic fractures emanating from each perforation cluster. Typically fractures created at the outer perforation clusters create “stress shadows”, i.e. increases in compressive stress in the minimum principal stress direction, which limit the growth of fractures growing from interior clusters; this is confirmed by modelling [1, 2, 3]. An example of this can be seen in Figure 1 which shows the final configuration of simultaneously propagating fractures from multiple, evenly spaced clusters when there is no perforation friction. The inner fractures are substantially shorter, reproducing the results by Bunger and Peirce [3]. The inner fractures also have substantially smaller widths.One approach to equalize the growth of simultaneously propagating fractures from a horizontal wellbore is by using limited-entry perforating as a method to equilibrate the flow rates into each of the different perforation clusters. Perforation friction is caused by the finite diameter of the entry points into the formation, and leads to a pressure drop across each perforation which is proportional to the flow rate squared. Fractures that take more fluid have a higher fluid velocity through the perforations than fractures receiving less fluid. This causes a larger pressure drop between the wellbore and more rapidly growing fractures, compared to the same pressure drop between the wellbore and the fractures that grow more slowly. Because pressure within the wellbore is approximately the same at each entry point, the larger pressure drop leads to less pressure being delivered to rapidly growing fractures, thereby decreasing their ability to propagate and reducing the amount of fluid they are able to receive. Because the mass rate of injection into the wellbore is constant, this forces more fluid into the fractures that were propagating more slowly, increasing their growth rate. It also increases the pressure required to drive fluid injection. The balance of these effects makes the system largely self-regulating and delivers more balanced fracture growth. While this effect is well known, it is often neglected in current numerical models."

Jan 1, 2015

By D. S. Campbell

THE chief factors influencing the decision to build the Big Missouri mill underground were the topography of the country and the climate. The location underground assured certain saving in the cost of operation, such as the hearing of the mill, shovelling snow, and handling ore, which, over a period of time, would offset the greater initial cost of the mill excavation and machinery installation underground, as compared with the cost of a like plant on the surface. At Gilman, Colorado, where conditions are somewhat similar, the Empire Zinc Company, at their Eagle mine, are treating their lead-zinc ore in a mill built entirely underground. Company officials made a study of this plant before proceeding with the mill at Big Missouri. LOCATION, CLIMATE, TOPOGRAPHY The Big Missouri mine is situated on the Upper Salmon river, 22 miles north of Stewart, B.C., which is at the head of Portland canal, a narrow natural channel which penetrates 100 miles inland from the coast into the Coast Range mountains. Stewart, the distributing centre for the district, is about 600 miles north of Vancouver. The Big Missouri claims lie on and down the sides of the Big Missouri ridge, which extends north and south between the Salmon River and Cascade Creek valleys. The ridge rises to an elevation of 3,600 feet, is about half a mile wide, and to the east slopes down to the Joker flats in Cascade Creek valley. The Big Missouri camp is located on the flats at elevation 2,800 (see Figure 1). Preliminary development of the property took place from this point with an adit driven under the ridge. The western side of the ridge slopes steeply down to the Salmon glacier at elevation 1,900. Ore found on the 2,850 level extended down, and, in order further to explore the ore-body, the 2,850 level was driven through to the west side of the ridge, a surface incline tramway was built, and a lower tunnel driven at elevation 2,350, five hundred feet below the original 2,850 level, from the west side of the ridge. This tunnel development avoided the necessity of sinking, which would have been costly, as the mine makes a great deal of water (see Figures 1 and 2).

Jan 1, 1938

By J. E. McMenamin, R. B. Hall

"With the emphasis in the past decade on larger and more efficient equipment for open-pit operations, the Normandie mine of the Asbestos Corporation has followed the trend, switching from the smaller type of percussion drills to down-the-hole rigs. One 5 Y2 -in. percussion drill is still in use, but is limited to a ""smooth blasting"" role or to the control of the slope on final benches.In keeping with the times, an attempt was made to eliminate, as much as possible, the use of high explosives and to maximize the percentage of ammonium nitrate -fuel oil mixture. As the concentration of ground water increased with increased mining depths, small pumps were initially employed for the dewatering of boreholes. This proved unsuccessful, and a hole-blowing rig was built and a conversion to plastic liners made. The acquisition of a bulk-mix AN-FO truck has permitted the changeover from an AN premix to an ammonium nitrate prill -fuel oil combination at the borehole."

Jan 1, 1966

By Wm. F. Wuest

INTRODUCTION THE Western Canada sedimentary basin has one feature in common with the Precambrian Shield area: it also was a great chemical laboratory. The mining industry of Canada exploits the end products of chemical experiments that occurred on the Shield during periods of repeated disturbances in Precambrian times. The petroleum industry on the other band exploits what also appears to be the final results of chemical experiments that took place throughout all of post-Precambrian up to Tertiary times. Since the subject of this paper is a factual study of Alberta well waters, no attempt is made to answer significant questions pertaining to the probable role waters play in the generation of oil, or to the significance of the effects of structure and depth on waters. Data from several hundred well-water analyses were compiled by the writer in a series of charts and diagrams, of which those included in this paper are representative. Early studies indicated the possibility that outstanding anomalies in general concentration of waters and in greatly increased concentration of elements such as calcium, magnesium, bromine, and iodine for example, might be expected from wells that produced oil or were in the immediate vicinity of producers. The water analyses from wells which? were drilled at a later date did not confirm this possibility, and it is suggested that, aside from their initial value to the petroleum engineer or to. those interested in the commercial possibilities of brines, no definite significance as an aid in oil discovery can be attributed to water analyses.

Jan 1, 1951

About Barrick Paste Backfill at Barrick Goldstrike Rodeo Paste Plant Cyclone Lab Testing Challenges and Lessons Learned Future Barrick Projects

May 1, 2013

By V. Ushakov, P. Bogdan

Daily production scheduling in a highly dynamic smelter environment has always been a great challenge for the operation management due to a significant amount of uncertainties. Planned and unexpected equipment failures, various energy outages, inaccuracies in flow and mass balancing, manpower availability conflicts and other constraints make the job of daily production planning exceptionally difficult. This paper discusses a general scheduling approach utilized by the production management of the Phelps Dodge Miami Smelter (the Smelter). It also describes logical assumptions and some practical software solutions that have been exploited by the Smelter managers to assist the front line supervisors in dealing with daily planning activities for several years.

Jan 1, 2007

By John J. Laffin

"IN THE BOOK that has been rated the best seller of all time, it is predicted that man will earn his livelihood by the sweat of his brow. Apparently man has accepted the statement as a challenge and has been attempting to refute it ever since, as he continues to transfer the workload to his inanimate servants - the many types of machines and other labour-saving devices that are available to assist or perform for him in the normal tasks of the day. The history of the evolution of the use of energy takes us back to primitive man, who existed in a very low energy environment, the only energy available being his own muscle power. Although man took a great leap forward when he discovered fire, which was used for lighting, heating and cooking, he still depended upon his own muscles for power. Early man's greatest achievement was probably the invention of the wheel, which permitted him to utilize the muscle power of animals. While still in a very primitive state when viewed from the perspective of the twentieth century, man, with fire and the wheel, had achieved a standard of life far exceeding that of his predecessors. Looking beyond the very basic elements of human energy, fire and the muscle power of animals, we find the next additions of energy coming from man's mastery of other elements of nature. The Phoenicians utilized the power of the wind and the Romans adapted the energy of falling water to the water wheel."

Jan 1, 1972

By R. R. Montigny

A brief description is given of the history, location and geology of the Granisle Copper Limited operation on Copper I land in Babine Lake. Detailed information is given with regard to pit design, planning, drilling, blasting, excavation and haulage. Equipment maintenance and mining costs are also presented.

Jan 1, 1971

By Melvin S. Taylor

The environmental control program at Cassiar Mine is an active one involving government, unions and company personnel all working together to achieve a goal- "A clean and safe working environment". This can only be achieved by utilizing three of Cassiar's most important resources; i.e., people, time and money. Past environmental programs have more than proved that the goal can be reached and. with the future programs now in progress. Cassiar Asbestos will achieve its environmental goals.

Jan 1, 1978