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By J. A. Russell

AS THE LOCAL electric generating plants increased in size and capacity and costs of producing electricity came down, it became apparent that it was no longer good economy to operate individual boiler plants at the Company's various collieries to power steam hoists and compressors. Great economies could be made by burning the Coal at central power plants and using electric power at the collieries. During the period after the end of the war, a steady and continuing programme of replacing first the smaller steam-driven units, and later the steam-driven compressors, was undertaken, and finally the larger hoists, those at No. 12 Colliery in New Waterford and No. 20 Colliery in Glace Bay, were the last units operated by steam.

Jan 1, 1958

En quoi consistent les études de suivi des effets sur l?environnement (ESEE)? Les ESEE constituent une méthode de suivi scientifique que l?on peut employer pour déterminer la santé des écosystèmes aquatiques (qui peuvent être touchés par l?activité humaine) et l?efficacité des mesures de protection de l?environnement. Les ESEE sont des évaluations scientifiques itératives du poisson, de l?habitat du poisson et des ressources halieutiques. Le programme comporte des phases séquentielles de deux à six ans de suivi, d?interprétation et de compte rendu au cours desquelles la fréquence et le type de suivi dépendent des résultats des études précédentes. Le programme des ESEE pour les mines de métaux est fondé sur un accord conclu à l?unanimité entre les intervenants. Les exigences du programme et les guides techniques connexes ont été élaborés à la suite d?une consultation multilatérale à laquelle ont participé les représentants du secteur privé, du gouvernement et des collectivités. Toutes les mines assujetties au Règlement sur les effluents des mines de métaux (REMM), aux termes de la Loi sur les pê ches, doivent procéder à une ESEE dans le cadre de l?autorisation qu?ils ont reç ue de rejeter des effluents. Le REMM a été enregistré le 6 juin 2002 et publié dans la Partie II de la Gazette du Canada le 19 juin 2002 (SOR/DORS/2002-222).

Nov 1, 2002

By Leslie B. English

"HistoricalWHILE DIGGING caves and underground passages for living quarters, primitive man must have had some means of illumination. Most likely he used pieces of wood or slim bundles of reeds or grasses as torches, perhaps steeped in animal fats to give more light. If this is so, we may accept these as the first means of underground illumination. Very little was clone to improve lighting devices for many generations, but slowly there was developed a fount holding fatty oils, with a spout in which was inserted a form of wick.Actual mining. for metals first of all, was started about 3,000 B.C. Some of the old Greek and Roman records refer to the use of torches underground, and some evidence of clay lamps has been found. Candies came into use some time during the first century A.D. When coal mining began about the 14th Century in England, candles were used for illumination because of the ease of manufacturing and handling them. Open oil-lamps came into use early in the 16th century -Agricola, in his De Re .Metallica, written about 1540. pictures a miner with such a lamp. However, the expense of these was so great that candies still continued as the general means of underground lighting.Unfortunately, as miners went deeper underground, they encountered a mysterious gas which. upon coming in contact with open lights, flamed violently, resulting in explosions and accompanying loss of life. The first reference to the results of these gas explosions appeared in 1621. No help seemed to be available. The gas was given off when the coal was mined and the miners could not see without lamps. Attempts were made to use the phosphorescent glow from partly decayed fish, fish skins, and fungus, also to bring daylight clown into the workings by means of a series of • mirrors; •but these means of illumination proved to be impracticable."

Jan 1, 1955

By R. A. Bergman, C. A. Pickles, J. M. Toguri

"Black calcium cyanide is utilized mainly as a reagent for gold extraction. It is produced by reacting calcium cyanamide, sodium chloride and calcium carbide at temperatures in the range of 1200°C to 1400°C in a smothered arc furnace. The equivalent sodium cyanide content of the product is in the range of 45% to 50% and the calcium cyanamide conversion efficiency is in the range of 90% to 95%. Since black cyanide contains impurities such as salt and lime and also because the conversion efficiencies are below 100%, the product contains unwanted materials which significantly increase the shipping costs.The impurity content of the raw materials can not be lowered without increasing their cost and/or the processes to produce them, and therefore the present research was focussed on studying those factors which affect the cyanide grade. The major variables investigated were: the heating rate, the reaction temperature, the salt to cyanamide ratio, the nitrogen content of the calcium cyanamide, moisture additions and calcium carbide additions. It was found that each of these variables had a significant effect on the product grade. The highest cyanide content of the product was obtained for salt to cyanamide mass ratios of 0.55 to 0.60. The salt reduces the decomposition rate of the cyanide and, therefore, at low salt to cyanamide ratios and at higher temperatures, the product grade is decreased. It is likely that the salt evaporates at the higher reaction temperatures and this decreases the cyanide capacity of the melt. High heating rates minimize the residence time and thus salt evaporation is reduced and higher grades can be obtained. As expected, the cyanide content increased with the nitrogen content of the cyanamide. Calcium carbide additions resulted in an increase in the product grade. The presence of small amounts of moisture in the charge caused a significant decrease in the cyanide content of the black cyanide. An equilibrium reaction is postulated in order to explain the black cyanide process and in particular the effect of calcium carbide on the product grade."

Jan 1, 2002

By Andy Lemay

Vale (previously known as CVRD) is: ? The second-largest mining company by market capitalization (NYSE:RIO) ? Headquartered in Brazil ? Global workforce of over 100,000 employees including outsourced workers. Vale Inco Limited is a wholly?owned subsidiary of Vale Vale Inco Limited ? is based in Toronto, Ontario Canada: ? Operations and Projects in 20 countries ? Marketing Network extending to 40 countries ? Over 12,000 employees worldwide ? Last years sales of US $8 Billion

May 1, 2008

By David Evans, David Barnes, Robert Raponi

"The Williams Mine processes, on average, 6,450 t/d of gold bearing ore using two parallel grinding circuits, leaching and C.1.P., carbon stripping, electrowinning and refining. At present, each grinding circuit consists of a SAG mill in closed circuit with a spiral classifier and a ball mill in closed circuit with two stages of cyclones.Since grinding has always constituted the largest portion of milling costs, the Williams Mine has been proactive in trying to reduce such costs through innovative changes. One project under consideration is the replacement of one spiral classifier by a vibrating screen.This paper discusses the testwork performed to evaluate the replacement of one spiral classifier by a vibrating screen, and the preliminary engineering performed to date.IntroductionThe Williams Mine, located in northwestern Ontario, approximately 40 kilometres east of Marathon, is part of the Hernia gold camp. The mine is operated by the Williams Operating Corporation and is owned by the Teck Corporation and Homestake Canada Incorporated. Operation of the mine started in October 1985 at a rate of 3,000 t/d. After a mill expansion in August 1988, throughput increased to 6,000 t/d. Production has increased steadily since the mill expansion and in 1995, an average of 6,450 t/d of ore was processed at a recovery of 95.1 %."

Jan 1, 1997

By N. R. Thote, J. L. Porathur, C. P. Verma

Highwall mining is a highly mechanized coal mining method associated with several advantages, such as a very high production rate (approximately 3,000 t/d) and low production costs. There is no requirement for underground support, ventilation, or blasting. Production leads to added recovery, which is otherwise lost in the ultimate pit. The use of highwall mining can bridge the gap that exists between supply and demand in the energy sector. This paper presents a brief review of highwall mining technology, including current status, analysis tools, and design techniques. In addition, it identifies important parameters from the analysis of failure case studies.

Jan 1, 2014

By Hans Lundberg

Introduction Today, geophysical exploration is recognized as a special science wedged between geology and mining. Universities and technical institutes have special professors teaching geophysics applied to oil and ore prospecting. The list of literature on geophysical exploration has grown from practically nothing at all some twenty-five years ago to ~ several thousands of books, some of them very imposing volumes. Most of the methods now used have been developed since the first World War, and very large systematic exploration campaigns have been carried out in many places, in many countries. It has been rather difficult to obtain enough information as to what is going on in Canada. However, since the Associate Committee on Geodesy and Geophysics of the National Research Council became more actively engaged in promoting geophysical research, it may be easier to obtain information and, in the future, the quarterly issued Canadian Geophysical Bulletin may throw considerable light on the current geophysical activities in Canada. Some twenty crews have been engaged the last few years in geophysical prospecting for ore. In the United States, between 500 and 600 crews are employed exclusively in geophysical prospecting. Most of these, however, are engaged in oil exploration. During the winter 1942-1943, the German Government employed some fifty crews on geophysical exploration, and some ten crews were working for private enterprises.

Jan 1, 1948

By B. Simser

Noranda?s Brunswick mine is a 10 000 t/d producer of lead-zinc-copper-silver ore that has been in operation since 1964. Mining of this multiple lens deposit is primarily by blasthole stoping techniques between 400 m and 1200 m below surface. The combination of a high overall extraction ratio, an overall steeply dipping tabular shape, and high horizontal stresses (twice the vertical) have elevated the induced stress regime to levels comparable to much deeper operations. Improved mine design, and a better understanding of how the rock mass responds to mining in high-stress environments is essential to improve overall recoveries and maintain safety. Seismic monitoring has proven to be an essential tool at Brunswick, for both short-term safety of workers, and long-term strategic planning. Practical case studies illustrate how seismic data, particularly source parameter information, can be used to measure the rockmass response to mining and improve mining layouts in difficult regions. As the global trend continues toward mining in deeper, higher stress environments (e.g., South African Witswatersrand Basin, Sudbury Basin) and as local extraction and thus ground stresses continue to increase in existing deposits, seismic monitoring will play a critical role in mining safely and economically.

May 1, 2004

By B. Simser, V. Falmagne

"Noranda’s Brunswick mine is a 10 000 t/d producer of lead-zinc-copper-silver ore that has been in operation since 1964. Mining of this multiple lens deposit is primarily by blasthole stoping techniques between 400 m and 1200 m below surface. The combination of a high overall extraction ratio, an overall steeply dipping tabular shape, and high horizontal stresses (twice the vertical) have elevated the induced stress regime to levels comparable to much deeper operations. Improved mine design, and a better understanding of how the rock mass responds to mining in high-stress environments is essential to improve overall recoveries and maintain safety. Seismic monitoring has proven to be an essential tool at Brunswick, for both short-term safety of workers, and long-term strategic planning.Practical case studies illustrate how seismic data, particularly source parameter information, can be used to measure the rockmass response to mining and improve mining layouts in difficult regions. As the global trend continues toward mining in deeper, higher stress environments (e.g., South African Witswatersrand Basin, Sudbury Basin) and as local extraction and thus ground stresses continue to increase in existing deposits, seismic monitoring will play a critical role in mining safely and economically."

Jan 1, 2004

By C. W. K

This little sketch of the late Willet G. Miller, Provincial Geologist of Ontario, is intended to be neither a biography of his career nor a eulogy of his life. His biography has already been written in an incomparable manner by Mr. T. A. Rickard, his eulogy by Canon Cody. What more can be said of Dr. Miller than is summed up in the words of that great Canadian divine, Canon Cody, that he was "Big in body, big in heart, and, as we learned, big in brain." This article, then, will merely record a few personal reminiscences of the man himself, and while they are necessarily disjointed, they may at least serve to illustrate certain traits in his character which are not generally known or appreciated outside of the circle of his intimate friends. In the latter part of May in the year 1904, Willet G. Miller, with two? assistants, set out for the small village of Haileybury to begin his geological work in the area a few miles to the south which he was soon to name Cobalt. At that time the Timiskaming and Northern Ontario railway was not finished, although the right-of-way was cleared and partly graded. The nearest railway station was on the Canadian Pacific at the south end of lake Timiskaming, from which point the old steamer Meteor carried passengers and freight up the long, narrow and deep waters of lake Timiskaming, a very pleasant trip of some sixty miles. On this particular trip there was a fairly large crowd on board consisting of settlers going into the clay belt north of lake Timiskaming, of lumbermen, and of a few merchants and commercial travellers who were interested in the small business centres of Haileybury, New Liskeard and Ville Marie. Scarcely any attention was paid to the reports of the newly found silver deposits, although the daily papers had announced discoveries in the district six months before. As a matter of fact, the chief excitement on board was afforded by a moose, which, in swimming from the Ontario to the Quebec shore of the lake, crossed the bow of the boat, the captain steering to within a few yards of the terrified animal.

Jan 1, 1925

By Peter Broad

"Extracting any metal, especially specialty metals and rare earth elements, requires an in-depth analysis of the costs and potential revenue as well as a due diligence study of other stakeholder interests. Rare earth projects are generally in the billion dollar US range or above, and thus failure to accurately predict any loss of revenue caused by impurities within the product or additional effluent treatment costs can destroy an otherwise viable study. Two prime sources of input impurity are considered: impurities in the material feed and from reagents. The effect of these impurities factor on both the product (in reduced revenue) and on residual “tailings” that may incur additional unforeseen costs.INTRODUCTION“Truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident” – Arthur SchopenhauerThe era of unscoped, unbudgeted construction ended about 150 years ago. Today’s engineer must design with confidence; but do so amidst proprietary secrets and unfamiliar pollutants, which present a myriad of interesting challenges. Is it possible to build a viable rare earth plant to a realistic budget, without destroying that which we cherish? Some see this as contradictory but in reality it is the only viable option.WHEN GOOD PROJECTS FAILWithout rare earths the Copenhagen agreement might be null and void. Running a wind turbine with a 30 tonne conventional magnet requires some hefty engineering and prohibitive investment. Despite their ‘Green metal’ applications, production of rare earths have created environmental nightmares, as Folger stated in 2011 when visiting Baotou, or has Jaing Mainheng who has been quoted by Ambrose Evans-Pritchard 6 Jan 2013. This comment is not a criticism of China; the details are from a 2012 white paper published by the Chinese Government that initiated a $6 billion environmental clean-up. Nor is China unique; other plants have had problems as well. There were toxic leaks in the 1990s from Mountain Pass, and the Mitsubishi Bukit Merah Plant (built in Malaysia in 1958) required a $100 million clean-up."

Jan 1, 2016

By A. B. Rossetti

"THE MISSION TO Offshore Scotland was in my opinion a very worthwhile venture, as it indicated the scope of the offshore oil and gas business and how we might exploit it to the fullest here in Nova Scotia - if our offshore fields eventually become producing fields. The writer was able to attend a considerable number of lectures and as a result gained some valuable know-how on the engineering design, financing and operation of the North Sea oil industry. There are many new fields of technology that had to be developed to overcome the North Sea's hostile environment and a great deal of the same technology will have to be developed to win oil and gas from our continental shelf. The visit left me with several impressions, which in the main are:(1) The high order of investment required to develop offshore oil. The investment ranges from 10 to 20 times that required for a similar output on land. Each barrel of oil costs on the average of about $2,- 500 per barrel per day.(2) Because of the high investments required, before the first oil is produced the field must be brought into production at the earliest possible date and initial lead time from decision to production is less than four years. In the British Petroleum field, working at a depth of 450 feet will require an investment of $900,000,000 to develop a production of 400,000 bbl per day. (3) The size and complexity of equipment required is beyond anything ever imagined. Problems which must be overcome are such factors as water depth, wind velocities, wave height, wave period, long periods of darkness, low temperatures, distance from land, and fog."

Jan 1, 1973

By John C. Wilmot, Robert E. Brewer, Royce J. Smith

In March 2003, Phelps Dodge started up an innovative pressure leach facility for processing copper concentrates at the Bagdad mine in Arizona. This paper describes the development of the concentrate leaching plant at Bagdad and the operational results from start up to present. Optimization efforts and an approach to mineralogical modeling of the concentrate to calculate oxygen utilization are also presented.

Jan 1, 2004

By J. G. Kelly, C. P. Brown

"In June 1983 a new borehole hoisting system was commissioned at Sherritt Gordon's Fox Mine. Twelve hundred tons-per-day of ore from the 2600 and 2800 levels are being hoisted to the 2000 level through an 8-jt diameter bored winze. This new method replaces the diesel truck haulage system which had been in operation at the mine since 1975.A study was initiated in 1980to determine the most effective method of achieving the required production. The study examined several hoisting alternatives including: expanding the existing trucking system; converting to electrically -powered truck haulage; and deepening the skip compartments of the existing main shaft. The alternative selected as the hoisting method most suited to the requirements was borehole hoisting.Development of the new system commenced in April 1982. Underground excavations included 700 feet of 8-ft diameter borehole, a hoistroom and headframe, storage bins, and a grizzly and rockbreaker station. Equipment installations included: a 5-ft diameter double-drum Nordberg hoist; a counterweighted Kimberley-type skip; two rockbreakers; and the steel sets in the winze. These installations were completed in June 1983. Some problems were encountered after the initial commissioning but these were solved, and since August 1983, the system has proven that the designed capacity is achievable within expected costs."

Jan 1, 1985

By C. O. Brawner, J. Kalejta II

"The classical approach to control rock fall and ravel in open pit mining has been to use catch benches. The width and volume of benches is most dependent on the bench height, size of loading equipment, blast damage to the face and mining regulations. This was compatible with open pit slopes of less than approximately 45 degrees.As our understanding of rock mechanics and blasting control has improved over recent years, much steeper rock slopes can be developed at many open pit mines. However, narrower benches result in less rock fall capacity.The transportation industry has been very successful in using catch fences to protect highways throughout North America and Europe for years. The authors recommend that cable and ring net fences have a potential major application in open pit mining to allow steeper rock slopes with significant economic benefit. This paper outlines the application, design and operation of catch fences in surface mining for specific conditions. Typical case examples are presented."

Jan 1, 2002

By D. C. Crothers

"What is new in air compressors? A good deal - the designers have been keeping pace with technical developments in related fields and also contributing new techniques of their own. Plant reliability no longer requires bulky slow-speed machines. Even the reciprocating machines, which still provide the most efficient method of compressing air, have been greatly reduced in size and installation cost for a given capacity rating. New materials and fabrication techniques are being used, by most manufacturers, to produce less costly plants in total. Many packaged plants are available, which generally means a more complete assembly for shipment. This type of construction offers savings in handling and erection costs at the site. A warning is in order, however - the extent of packaging in any given plant should be investigated carefully to determine what is included and just what field costs can be realized. A suggested specification has been offered for consideration when studying comparative costs. Rotating machines intrigue many because of their potential as regard fewer wearing parts, higher speeds and hence smaller units, utilizing less expensive drivers, and lack of contamination of the compressed air by lubricants. The inherent shortcomings of these machines - lower •efficiency and capacity control - have been much improved lately, and this type of plant is now becoming quite popular. Noise control, of much concern to everyone, is another development that has received considerable attention.Systems for efficient capacity control and continuous monitoring of compressor operation offer additional reliability and low-cost operation of the modern compressed air plant. Accessory equipment and its effect on over-all plant operation is also considered."

Jan 1, 1972

By Chris Brown

"The Island Copper plant was designed and built by Fluor Utah Ltd, in conjunction with Utah design staff, Originally designed to treat 33,000 tons/day (t/d) of ore, the current average milling capability is 38,000 t/d (Nov'74). The first of six semi-autogenous grinding lines was brought on line in October 1971, startup of the remainder being governed by equipment delivery schedules.The summer of 1973 saw the start-up of an additional three ball mills, and attainment of the present production level. The current process flowsheet is shown in simplified form.CRUSHINGThe crushing circuit is relatively simple, comprising single stage crushing of the ore followed by screening to fine and coarse fractions.The crusher is a 54 x 74in. Allis Chalmers Superior Gyratory with a setting of 9-lOin., driven by a 500-hp motor. Trucks dump on three sides of a rectangular dump pocket. An 84in. x 20ft. link belt apron feeder draws crushed ore from a 250-ton surge bin below the crusher, discharging onto a 72in. wide inclined steel cord conveyor belt. A fixed splitter box at the conveyor discharge separates feed to two parallel Jeffreys 6 x 20ft. vibrating grizzlies for screening into +4in. and -4in. fractions. The fractions are collected on short reversible conveyors which feed the coarse and fine ore stacker conveyors. Trippers distribute ore to outside stockpiles adjacent to, and above, the concentrator grinding 'floor."

Jan 1, 1975

By R. Laplante, P. Radziszewski, P. De Ciccio

"Predicting the effect of wear can lead to improved control strategies that can possibly minimize the risk of catastrophic failure due to wear while maximizing useable life. In the field of geological exploration, diamond drill rod wear illustrates just such a case. Wear conditions vary with geological formations and compositions. The objective of this paper is to determine a general relationship, based in theory and practice, that will approximate drill rod wear and therefore predict remaining drill rod life in the context of Canadian, Australian and South American drilling campaigns. Simulation results allow the definition of simple graphical tools that permit the estimation of the potential drill depth remaining on a given drill rod string. IntroductionWear, in many industrial processes, is an undesired phenomenon for which enormous efforts are made to control, if not eliminate. However, wear, in many other cases, is an intrinsic phenomenon of the given process. In such cases, predicting the effect of wear can lead to improved control strategies that can possibly minimize the risk of catastrophic failure due to wear while maximizing useable life. In the field of geological exploration, diamond drill rod wear illustrates just such a case where abrasive conditions vary with geological formations and compositions.A number of studies have been published on drill rod wear especially with regards to the petroleum industry over the last thirty years (Lewis, 1968; Rollins, 1968; Smith, 1978; White 1978; Rowe and Wilson, 1981; Cheng, 1982; Eustes, 1986; Dudman et al., 1989; Besaisow et al., 1990). Of these, most studies covered management techniques (Rollins, 1968; Smith, 1978; White, 1978; Rowe and Wilson, 1981; Besaisow et al., 1990) and some described case histories (Cheng, 1982; Eustes, 1986; Dudman et al., 1989). However, little (Lewis, 1968) was presented that could aid in predicting wear in the particular case of diamond drilling in the metal mining industry.The objective of this paper is to determine a general relationship, based in theory and practice, that will approximate diamond drill rod wear and therefore predict remaining drill rod life in the context of Canadian, Australian and South American diamond drilling campaigns."

Jan 1, 2002

By E. W. Vekris

Patents are playing an increasingly important role in the business world. A diverse patent portfolio can enable a company to secure a monopoly within the market, which can provide a competitive advantage over competitors. At the same time, possessing a diverse patent portfolio greatly increases the value of a company's intangible assets. This paper provides an overview of the patenting process as it pertains to the fields of metallurgy and mining, and summarizes some general patenting strategies. A review of new "green technology" initiatives recently adopted by Patent Offices around the world is also provided.

Jan 1, 2011