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By Daniel Murray

"ACCIDENT PREVENTION in and around coal mines presents many problems of a type which are not encountered in any other industry. This is particularly true of the coal mines in Nova Scotia, where the underground workings are very extensive and the area of exposure to workmen is very great.Roof conditions at the coal faces and in the waste change very rapidly, almost from hour to hour, and it is at these places that the greatest dangers exist and where most mine accidents occur. It is only natural, therefore, that our attention, as far as accident prevention is concerned, should be concentrated •at the coal faces and in the waste, especially in mines where the longwall system is used in the operation •of the seam.It has been said that no hard and fast rules can be set down for timbering at the coal faces and in the waste in the coal mines in this area. We do not subscribe to this theory, however, for the following reasons:On the longwall faces in No. 18 Colliery of the Dominion Coal Company, Limited, where the 'Dosco Miner' has been in operation and where there is a very rigid system of timbering and roof supports, which is strictly followed, only one compensable accident has occurred on those faces from May 2ndJ 1950, to the time of writing this paper, February 3rd, 1953.The 'Dosco Miner' has worked on four different longwall faces in this mine and has mined and loaded some hundreds of thousands of tons of coal."

Jan 1, 1953

By N. Schreithofer, M. Aspiala, R. Serna

The novel attachment timer apparatus presented in this paper serves as a diagnostic tool that allows the detection of changes in bubble-particle attachment probability and therefore floatability caused by alterations in the chemical environment and particle properties. The apparatus consists of six identical capillaries where bubbles with defined size are produced simultaneously in a measurement chamber. The bubbles at the capillary tips are placed in contact with the submerged particle bed for specific time periods, controlled with the help of automatic actuators. The advantage of the instrument is that hundreds of bubble-particle contacts can be measured automatically within a short time period. Microscopic pictures of each measured bubble are taken while recording the movement of the bubble before, during and after contact with the solid particles. The recorded pictures can be used to determine the actual bubble size and its corresponding deviation, and to detect the attachment of particles. The attached particles are collected in a detachable chamber for subsequent characterization. Furthermore, the device is portable and can be taken to the mineral processing plants for quick evaluation of particle-bubble attachment efficiency with particles and process water sampled directly from real processes.

Jan 1, 2017

By V. F. Hollister

Four conditions are commonly accepted as being needed for the development of native sulphur deposits in sedimentary rocks : (1) ample sulphate-bearing evaporite, normally anhydritic; (2) proximity to petroleum deposits; (3) a hydrodynamic system of communication between these two; (4) a stratigraphic or structural trap to prevent escape of the sulphur and sulphur -bearing reaction products. When any of these requisites are absent, apparently no significant residual bio-epigenetic sulphur deposit will form. These requirements are, however, satisfied in some areas, which include both the Triassic and Devonian evaporites of northeastern British Columbia.

Jan 1, 1977

By J. Qi

Based on the commercial steel 42CrMo (4140, SCM440), a new generation of CrMo steel was developed by increasing the content of Mo, adding the alloy element of V and Nb, and decreasing the content of P and S. This new CrMo steel has higher strength of 1500MPa and better delayed failure property. TEM and EDS were used to study the distribution and function of the alloying elements in this steel. A new EELS technique was developed to study the bonding strength of the grain boundary in the steel. The mechanism of strengthening of the new steel has been studied.

Jan 1, 2004

This paper discusses how elemental analysis of conveyed bulk flows in real time using PGNAA (Prompt Gamma Neutron Activation Analysis) technology has resulted in significant improvements in advancing plant control in mineral processing operations. Basis of operation of the PGNAA through belt, full stream, continuous, multi-elemental, real time analysis technology is explained. Capabilities and limitations in plant operating environments are discussed including comparison with other real time, online technologies through review of published information available for on-conveyor minerals applications. Case studies demonstrate benefits provided by this technology in two operating mines. An iron ore company had prior experience with the PGNAA analyser technology, implementing an early model in a minerals application in 2003 to develop confidence in its measurement performance and usefulness of the data. A number of analysers were subsequently included throughout the new plant design for extensive measurement and control of conveyed bulk flows, from conveying after mining through to rail load-out. A copper-gold company installed an analyser to address copper ore blending issues where an on-belt system was the only viable option for the degree of control required. Analyser suitability was evaluated through test work on site samples to determine customised multi-element precision guarantees for each application. Analyser results from normal operation are compared against laboratory analyses of multiple cross stream samples collected from conveyed flows to assess performance. Both projects discussed were able to realise benefits previously unattainable for plant quality control, surpassing capabilities of traditional technologies which were either unsuitable for measuring conveyed flows with adequate accuracy or in real time. Equipment payback within a few months was achieved for both sites. Through proven performance in these applications, the companies consider the technology an essential component in advanced plant control necessary in new process flow sheet designs, rather than an optimisation tool.

Jan 1, 2014

By G. H. Hope

"Pamour Porcupine Mines of Timmins, Ontario operates two 3,000 ton per day concentrators which receive ore from eight to ten mines in the area. The area milling concept was adopted by Pamour in 1971 and has been used successfully since then. The purpose of this paper is to discuss the advantages and the problems of area milling. Pamour Porcupine Mines Limited operates two 3,000 ton per day concentrators which receive ore from eight to ten mines in the Porcupine region. The area milling concept was adopted as the route to survival for Pamour and has worked successfully. HISTORICAL BACKGROUNDProduction of gold from the Porcupine region in Northern Ontario started in the early 1900's and has been continuous since that time. Some of the major operators were companies such as Mcintyre, Hollinger, Dome, Pamour, Paymaster and the list goes on. An underground survey would reveal hundreds of miles of drifts and raises. The main group of mines extends from South East of Timmins to the Pamour Mine, 15 miles to the east. During the lean years of the sixties when gold prices were low, labour costs were rising rapidly, and ore grades were dropping, many of the area mines closed down their operations."

Jan 1, 1981

By Côme Carbonneau

The ten -year case history of La Société Québécoise d'Exploration Minière (SOQUEM) is reviewed under the headings of the company's raison d'être, objectives, policies, structure and final goal. A brief analysis of its past operations is presented: aborted efforts, findings and developments. A projection is made of the future earnings, in terms of estimated present value, of its three main discoveries - Louvem , Niobec and Selim.

Jan 1, 1978

By Steve Dismuke, Tom Diment

In December 1994, Polaris decided to investigate the use of cemented rockfill (CRF) to supplement the existing frozen rockfill system. Extraction plans for the remaining ore reserves required a backfill with superior stiffness proper-ties and capable of developing high early strengths. Although CRF has been used success-fully at several mining operations, there was the additional challenge of making a reliable cemented product in permafrost conditions. There was also the challenge of procuring and storing one year’s supply (13 000 tonnes) of bulk cement. By the spring of 1995, following three months of research, test work and process design, the decision was made to proceed with the procurement and construction of a 3000 tpd batch plant. An ambitious completion date of December 1995 was set. Team Manufacturing of Langley, British Columbia was awarded the contract, complete with the considerable task of having the batch plant fabricated and ready for sea lift shipment by August, 1995.

Jan 1, 1996

By D. Mas Ivars, K. Suzuki, J. A. Vallejos

"A comprehensive geotechnical characterization has been undertaken at the El Teniente mine to describe and determine the rock mass behaviour strength properties of the primary copper ore. The Synthetic Rock Mass (SRM) modelling approach is used to simulate the mechanical behaviour of this heavily and unfractured rock mass. The micro-parameters of the model have been calibrated against mechanical properties and scaling laws for intact rock and veins, in order to represent virtual samples of four different geotechnical units. Results can be used to predict the rock mass scale effects, anisotropy, and brittleness properties that cannot be obtained using empirical methods.INTRODUCTIONThe primary copper ore at the El Teniente mine is described as very competent and massive, given that it exhibits a brittle behaviour (Rojas, Cavieres, Dunlop, & Gaete, 2000). This description is coherent with the geological description of the rock mass, which does not have discontinuities match as the definition provided by International Society of Rock Mechanics (ISRM, 1981). Only faults can be classified as discontinuities, but they are widely spaced. The primary copper ore has a high frequency of veins, where the cooper mineralization is hosted, these vein network structures are known as stockwork. Soft veins containing weak minerals as infill (chalcopyrite and anhydrite) control the disassembling of the rock mass during caving (Brzovic & Villaescusa, 2007).Presently, there are mainly two traditional methods used to estimate the strength of the rock mass: 1) determination of the strength envelope of the rock mass using scaling parameters from laboratory tests and 2) using numerical modelling based on back analysis of previous experiences of failure observed and measured in mining or civil excavations. The primary copper ore of El Teniente mine has no fractures; therefore, it is difficult to determine a rating that would enable to scale laboratory data, such as, RMR (Laubscher, 1977) or GSI (Hoek, 1994). This is the reason why the first option is not valid unless the entry data is manipulated or adjusted in order to obtain reasonable results. The second option requires, in general, a good characterization of a previous failure event in the rock mass, which is not always available. In recent years, new techniques of numerical modeling have been developed (PFC3D, ELFEN, Abaqus). Those methodologies are the third way to estimate the strength of the rock mass, but they are still in development. Particularly, the concept of SRM developed by Itasca is implemented in this study (Pierce, Mas Ivars, Cundall, & Potyondy, 2007; Mas Ivars et al., 2011), aiming to capture the real behaviour of the rock mass."

Jan 1, 2015

By T. W. Bingay

The production of both lead and zinc in Canada has steadily increased during recent years until today Canada ranks among the world's leading producers of both of these metals. The high prices which they have commanded have led to an energetic search for new deposits and also to an investigation of abandoned properties which, under the present conditions of better prices and more efficient methods of treatment, offer chances of commercial success. It is confidently expected that during the next few years success in both these lines of activity will further increase Canada's lead and zinc output, giving her a still higher ranking among the world's producers. In 1926, approximately 140,000 tons of metallic lead was produced from ores mined in Canada, and of this, 125,000 tons was refined in Canada at Tadanac, B.C. During the same year the production of metallic zinc from Canadian ores amounted to 68,000 tons, of which 62,000 tons was refined at Tadanac. History Of Lead and Zinc in Canada The production of lead in Canada is much older than that of zinc. The chief source has always been the interior of British Columbia. As earl y as the 'eighteen twenties', Indians and Hudson's Bay Company's trappers had discovered an outcrop of lead ore on the site of the present Blue Bell mine on the east shore of Kootenay lake, but it was not until1865 that active prospecting for lode deposits began. In the early nineties the activity of the silver-lead-zinc region of the Slocan reached its culmination and a steady production has been maintained down to the present time. Up to the end of 1924 the Slocan area produced over 38 million ounces of silver, nearly 300 million pounds of lead, and almost 122 million pounds of zinc.

Jan 1, 1927

By H. Rozovsky

"AbstractThis paper discusses the methods of handling air in a large asbestos mill presently being completed at the Jeffrey mine of the Canadian Johns-Manville Company in Asbestos, Quebec.The mill, being the largest single asbestos producer in the world and capable of handling over 14,000 tons of ore per day, requires vast quantities of air. A minimum of 2,500.000 c.f.m. is required or about 10 tons of air for each ton of ore milled.Short descriptions of the process and systems requiring this air are given, followed by details of the fans and filters which make up the heart of the mill.This 'draw through' system, located on the top or 12th floor, is an automatically .controlled volume-pressure system creating the required suction to draw .air throughout the mill building and its numerous air systems.The dry mechanical method of milling develops enormous quantities of airborne dust and fibre. A section of this paper is devoted to a description of the multiplicity of dust systems within a system to control, filter, and remove this dust.Finally, the paper describes the method of returning the filtered air to the• working floors or to the outside, with some notes on heat, humidity and dust counts.IntroductionGeneralTHE discussions in this paper deal only with operations where air movement is involved. No attempt is made to delve into production methods.The Jeffrey mine of the Canadian Johns-Manville Company, located about 100 miles east of Montreal, is the largest single asbestos producer in the world, being responsible for over half of Canadian asbestos fibre production."

Jan 1, 1955

By The Mine Staff

THE PROPERTY of the Lamaque Mining Company, Limited, ?is located in the Town of Bourlamaque, seventy miles east of Noranda, in Bourlamaque township, Abitrbi county, north western Quebec. Gold production commenced at Lamaque in April, 1935, with an initial mill capacity of 250 tons per day. The capacity was doubled in November of the same year, and in December, 1937, it further increased to 1,200 tons per day. During the war years the mill operated at a reduced tonnage, but in 1951 milling units were added along with complementary crushing and shop facilities to bring the capacity to 1,500 tons per day. Finally, in 1953, the capacity was raised to 2,000 tons per day, which rate is being maintained at the present time. The total production at Lamaque from April 2nd, 1935, to December 31st, 1956, has been 9,168,901 tons of ore from which 2,208,168 ounces of gold was recovered. The total value of this production , excluding E.G. M.À.*, was $77,869,653.

Jan 1, 1957

The primary steel industry of the Prairie Provinces consists essentially of three companies whose total annual melting capacity, as of January 1, 1963, was 333,000 net tons. These companies have steel rolling facilities. In addition, there are five other companies producing steel castings by melting scrap in electric furnaces which, with the plants having rolling facilities, gives a total annual furnace melting capacity of 380,000 tons. Since 1954, the annual production of steel ingots and castings has ranged from a low of 66,588 tons, in 1954, to a high of 211,138 tons in 1961. The present facilities on the Prairies for making steel ingots from scrap, and rolling them to produce light merchant mill products, appear to be sufficient for many years ahead. Steel scrap, as electric furnace feed to make steel ingots for the present line of products, will probably continue to be available at reasonable prices either on the Prairies or from the north-central United States. It is recognized, however, that residual elements in scrap may be-come of greater significance and necessitate more rigid control of scrap quality.

Jan 1, 1963

By H. H. Wang

Construction safety documents regulate significant safety actions and requirements by which construction workers or employees should abide in order to secure them from occupational hazard events. Therefore, facilitating faster identification of applicable safety requirements from the documents has become an important topic in the construction safety domain. To address the need in this regard, tools and techniques have been developed and research efforts have been made. One of the research efforts is to utilize ontology, a knowledge representation and reasoning approach, as the methodology to achieve the goal of identifying applicable safety requirements. In such ontology-based researches, the development and construction of the safety concept ontology is an essential task as the concepts and the relationships between the concepts both representing key safety knowledge need to be carefully identified. In this paper, the author focuses on the safety documents without predefined concept structure and aims to address the concept and relationship identification difficulties. Specifically, the author leverages the Formal Concept Analysis (FCA) methodology, a theory of data analysis that identifies conceptual structures among data sets, to mine and analyze the documents in order to discover safety concept structure and to further assist the development of the concept ontology for the construction safety documents. The author expects the application of FCA to construction safety domain can eventually benefit the ontology-based approaches for identification of applicable safety requirements.

Aug 1, 2013

By Oliver B. Hopkins

"WE HAVE patterned our lives on the things we take from under the earth's surface. Our civilization is built upon the ore from which we obtain our metals and the fuels which power the world as we know it.Today I should like to discuss with you a newcomer to the ancient mining industry. This lusty infant of which I speak is just a century old - the oil industry.While one doesn't commonly think of oil men as delvers in the earth, It was by sinking a shaft that the first oil was obtained commercially in Canada. Men sank a shaft in a ‘gum bed' in southwestern Ontario's Lambton county, not far from Petroilia, and distilled from the gum a burning oil That was just a hundred years ago. The gum was originally liquid petroleum which had seeped to the surface and lost most of its volatile components.Later, the miners dug down to •bed-rock and soon after they were not digging but were drilling wells, as they have been ever since. From the wells they obtained erode oil.What is crude oil? It is not an element like gold, silver or lead, •but a complex mixture of compounds. These compounds are made basically from two elements, carbon and hydrogen, and are called hydrocarbons (Figure 1).The remarkable ability of these. Two elements to combine in different ways gives crude oil its physical and chemical character. The lighter hydrocarbon compounds in it are gases, at normal temperature and pressure, and these are dissolved in the other, heavier compounds."

Jan 1, 1952

By Chan-ho Park

As the building has recently become bigger, higher, and freeform, a technology called BIM(Building Information Modeling), which is a key technology that integrates construction and IT(Information Technology), has been rapidly introduced and expanded. Because BIM technology offers various benefits, countries that introduced BIM early has been actively promoted. However, misperceptions of BIM are prevalent in countries such as South Korea that have adopted it relatively late, with lack of awareness of its fundamental purposes. Under these circumstances, transparent and quantitative performance assessment needs to be executed in order to eliminate the misperceptions, and to explain and revitalize the BIM introduction. These quantitative performance measure KPI (Key Performance Indicators) to be measured should be prioritized. As derive performance indicators in terms of the four types (financial, customer, internal processes, learning and growth), and performance management systems, Uses the BSC to seek a balance between short-term financial goals, values and the value of long-term goals. Uses the BSC(Balanced Scorecards) to derive performance indicators in terms of the four types (financial, customer, internal processes, learning and growth), and performance management systems, seeking a balance between the value of short-term financial objectives and the value of long-term objectives. Through this, the KPI (Key Performance Indicators) which is used for measuring the effect of the BIM will be generated and also the method that can determine whether the generated KPI figures are objectively inter-connected will be suggested as well.

Aug 1, 2013

By Daniel Hodouin, Claude Bazin

"This paper examines the economic advantages of tuning the operation of a differential Cu-Zn flotation circuit as a function of metal prices. Three operating strategies are considered in the analysis: 1) the operation of the circuit at planned copper and zinc concentrates grade with maximum recovery of both metals; 2) the operation of the Cu circuit at maximum copper smelter return per ton of ore and of the Zn circuit at a maximum zinc smelter return per ton of ore; and 3) the operation of the circuit at maximum copper and zinc smelter return per ton of ore. The second strategy tunes the copper circuit independently from the zinc circuit, while the third strategy tunes both circuits simultaneously IntroductionMetal prices play a very important role in the mineral industry (Malhotra and Dowling, 1991). In many cases, metal prices can be the basis for the GO/NO GO decision of a mining project (Malhotra and Dowling, 1991; Apostolides, 1983; Davis, 1996). This direct impact of metal prices on company revenues is highlighted in many annual reports. The 1995 Noranda Annual Report indicates that a variation of 10% of the copper price impacts its yearly revenues by $25,000,000. Some mine operators claim to mine stopes as a function of metal prices (Liimatainen, 1996; Hartman, 1992). This impact of metal prices is also recognized by mill operators that seek strategies to tune ore processing circuits to maximize revenues from the concentrate they sell to smelters (McKee, 1991; Barker et al., 1989; Hales and Ynchausti, 1994; Cipriano et al., 1995). In many cases the problem of tuning the operation of an ore processing circuit is complicated by the fact that the ore contains two or more valuable metals which have to be recovered into separate products. The Agnico-Eagle (Robitaille and Cousin, 1995) and Barrick East Malartic (Pelletier, 1996) Cu-Au mines are examples, as well as the Cu-Pb-Zn Brunswick mine (Shannon et al., 1993) or the Cu-Zn Louvicourt (Whiteway, 1995) and Selbaie (Wright, 1995) mines."

Jan 1, 2000

By A. H. A. Robinson

Until quite recently-practically up to the present time-all but an insignificant amount of the copper produced in Canada was shipped abroad in the form of ore, matte, blister, etc., there to undergo the further treatment necessary to bring it to the refined state in which it is required by fabricators of copper. Consequently, Canadian manufacturers were forced to import nearly all the copper required in their business; and a considerable portion of the ultimate value to be derived from a Canadian raw material was lost to the country of its origin. In the early days of Canadian copper mining, when both the production and consumption of copper in Canada were much smaller than now, such a condition of affairs was perhaps economically unavoidable, and, in any case, was not a matte~ of sufficient importance to attract general attention. Later on, however, when there had been large and rapid increases both in the production and consumption of copper in Canada, it formed the basis of much adverse criticism, deserved or not, of producers of Canadian copper-criticism that became intensified during the war and subsequent years. Happily, the chief grounds of complaint have now been removed, and there are today copper refineries in Canada, either operating or under construction, that are capable, in the aggregate, of turning out amounts of refined copper greatly in excess of any indicated Canadian consumption.

Jan 1, 1931

By L. Gawlik

Since the beginning of the 20th century, coal has been the world?s main source of primary energy. In the last few decades, consumption of coal has gradually decreased in some European countries and elsewhere due to the introduction of other energy sources. Regardless, industry continues to use solid fuels for energy production despite of their association with carbon dioxide emissions (about 7 billion Mg). For global development going forward, it is important to estimate what level of energy consumption can be expected as far into the future as the next few decades. To answer this question, specialized global institutions such as the International Energy Agency, the World Energy Council, the World Coal Institute, the U.S. Energy Information Administration, the International Institute for Applied Systems Analysis, as well as oil companies (BP, Shell), conduct periodic forecasts of world energy consumption. The development of such forecasts is very complex because their reliability is influenced by many factors that are difficult to estimate, such as economic development, population growth, climate change, and public awareness. We are all aware that the global demand for electricity will rise significantly in the coming years as a result of anticipated population growth, industrial development, rising living standards, and the general development of civilization. The world?s mineable resources in 2010 were as follows: coal 665.6 million Mg, brown coal 195.4 billion Mg, oil 163 million Mg, and natural gas 185.5 billion m3. The annual global primary energy demand in 2008 was more than 12 billion toe (12,267 Mtoe). In 2006, electricity production in the world amounted to 18,921 TW?h. The structure of the primary energy mix in TW?h (2006) was as follows: coal 41.0%; natural gas 20.1%; nuclear fuel 14.8%; hydro energy 16.0%; liquid fuels 5.8%; and other renewable energy sources 2.3%. The European Union (EU) is one of the largest coal consumers in the world. In 2010, the EU-27 produced 396.1 million Mg of brown coal, and 132.9 million Mg of hard coal; 188 million Mg of coal was imported from outside the EU. The largest hard coal producers in the EU-27 are Poland, Great Britain, Germany, the Czech Republic, and Spain; major brown coal producers are Germany, Greece, Poland, the Czech Republic, and Hungary. For many years, the Polish energy sector has been based on domestic fuel sources ? hard coal and brown coal. The characteristic feature of the Polish balance of primary energy resources is a very high share of coal ? much higher than the world average. Pursuing the decarbonisation of the Polish economy may jeopardize Poland?s energy security, leading to a significant increase in electricity prices, which would hamper the country?s economic development. Price volatility and supply uncertainty are now the dominant features of the international markets for oil and natural gas. The high share of these fuels in meeting energy needs is the reason for unrest in many countries, including those in the EU. Under these circumstances, coal may become the stabilizing element of EU energy security.

Aug 1, 2013

By Gerald Blackmore

"This paper suggests that with the settlement of long-term contracts of fifteen years' duration, with prospects of extension, the coal mining industry has, for the first time, a complete commercial justification for large-scale planning.The labour costs of coal production over past years are analyzed and, with the acceptance of the premise that the basic shift rates are certain to rise in the years to come, the paper suggests that forward planning should provide &r capital investment to make a traditionally labour-dense industry into a capital-dense industry.Automated methods of manpower deployment and timekeeping and the monitoring of all equipment back to a central control point are discussed as ail-important means of obtaining maximum utilization of high-cost capital investment.Principles of payment of the work-force, and the utilization of equipment 24 hours a day, seven days a week and the maximum number of days a year, are dealt with as means of achieving maximum capital utilization. Some of the new technical underground and coal preparation problems which will undoubtedly result from the concentration of workings and maximum machine utilization are discussed, and the author makes suggestions as to how these might be solved.In short, the author predicts that if the coal mining industry is prepared to recognize the problems and invest in modern equipment backed by highly trained staff. then the outcome will justify the high capital investment involved. He stresses the importance of human communications in achieving this end."

Jan 1, 1970