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By Arthur Dubé

An account is given of the developments brought about in the last fifteen years by metallurgical research in the field of heat treatment of steels. The practical aspects of these developments are especially emphasized. Methods of representation of the phase-change during austenitizing and sub-critical transformation of austenite are described and the importance of time-temperature-transformation charts for the planning of heat treatment cycles is shown. Special copies such as retained austenite and internal stresses developed on quenching are also discussed in some detail. Due to the interest shown currently in these problems, it has been thought advisable to describe briefly the underlying principles and present some of the results already available.

Jan 1, 1945

By D H. Sharp

The Quebec Cartier Mining Company produces iron concentrate for twelve months of the year from Port Cartier. This J>Ort is designed to handle ship varying in size from 3,000 to 100,000 d.w.t., requiring 50 feet of water at low tide. The harbour was built on shore for reasons of economy and layout, after considering many more conventional offshore designs. It provides for heavy oil bunkering, tanker off-loading, a heavy lift derrick and freight handling, besides ship loading and mooring. The weather for the previous fifty years was studied to enable wind and wave conditions to be accurately assessed for design purposes, and to determine probable lost time due to adverse weather conditions through-out the year. The first ship to be loaded was 60,000 d.w.t.; the second, 20,000 d.w.t. The latter entered the harbour after dark, under its own power, following a tug through the partly dredged narrow entrance. Large ships use tug assistance. Ships may leave the loading berth with the other berths occupied.

Jan 1, 1963

By Alan Jessop

A small group has been set up at the Dominion Observatory, Ottawa, to make a survey of terrestrial heat flow throughout Canada. Terrestrial heat flow is the heat rising from the interior of the earth and escaping at the surface, and is calculated from a knowledge of under-ground temperature distribution and the thermal conductivity of rocks. A small number of diamond drill holes are being sunk for the purpose of measuring temperatures below the surface, but the program is inadequate for a thorough survey. Mines and holes drilled for other purposes are being sought by the Dominion Observatory group to supplement their own drilling program. F ROM January, 1.962, to December, 1964, geo-physicists of many nations will be cooperating in the "International Upper Mantle Project." Unlike tl1e International Geophysical Year, which was mainly concerned with the fluid layers surrounding the earth, the Upper Mantle Project is an intensive study of the solid earth. Canada, with its large land area and extensive Precambrian Shield, is an active participant in the project.

Jan 1, 1964

By J K. Irwin

The authors discuss the application of drum and friction hoists under modern conditions and give four examples of friction hoists proposed for various applications. The paper concludes with a summary of the advantages and limitations of friction hoists relative to drum hoists. Introduction T H~ introduction of the multiple-rope friction hoist m the late 1940's has complicated the se-lection of the right hoist for a given job. Once such considerations as rope safety factor, drum to rope ratio, hoisting distance, tons per hour and/or service duty have been decided upon, the selection of a drum hoist is relatively simple. We now ask our-selves "which hoist -drum or friction? (See Figure 1 and Figure 2). When a friction hoist is a possibility we are immediately concerned with how many ropes to use, whether to hoist balanced or counter-balanced, whether a friction hoist will be flexible enough for the application and, of course, what the relative costs will be.

Jan 1, 1964

By A. F. Brock

Introduction During the past ten years, shaft sinking has been going on continuously at Inco and new shafts and shaft extensions have been sunk under a broad diversity of conditions. The Murray mine and the Stobie section of the Frood-Stobie mine have?been opened and a main hoisting and supply shaft has been sunk at each of these mines; No. 2 shaft at Murray was sunk initially from surface to 1,960 feet and is now being extended; No. 7 shaft at Stobie was sunk from surface to 3,105 feet. No. 2 shaft at Garson has been extended from 2,200 feet to 3,200 feet in depth. At Levack, No. 2 shaft is being extended from 1,860 feet to 2,850 feet for ore hoisting from the 2,650 lev el. At Creighton, No. 6 shaft, collared on 52 level, was sunk 1,740 feet to a total depth of 5,563 feet below surface. It is the deepest Inco working. At Creighton, also, No. 7 shaft is being sunk from surface to the 30 level to handle the ore from caving operations. Ail Inco main hoisting and supply shafts sunk during the past twenty years have been vertical rectangular shafts equipped with two cages and two ore skips. The cages are standard and interchangeable for all shafts except Garson No. 2; they are single-deck, 13 ft. 4 in. by 5 ft. 2 in. inside and are designed to carry a maximum material load of 16,000 lb. The man load is 48 men. Skip capacities at the several shafts vary from 8 to 15 tons. Forty-two hundred feet bas been established as the standard vertical lift, and the permanent hoisting equipment at each shaft is designed for eventual hoisting from that depth.

Jan 1, 1950

By A. Galip Ulsoy

This review paper is intended to provide, the mineral process engineer with an introduction to the concepts, terminology and practice of mineral process control. It also provides an extensive sampling of the vast body of literature relevant to this topic. The topics discussed include the principles of automatic control, instrumentation, mineral processing unit operations, process modeling and simulation, and process and plant control.

Dec 1, 1981

By D. A. Wheeler, Rémi Tremblay

"INTRODUCTIONDuring the last few years, through Column Flotation Company of Canada ltd, the Centre de Recherches minérales has worked on the column flotation of coal, phosphate, feldspar, talc, graphite, copper, lead-zinc and diamond ores. The operating companies and prospective deposits were located in Canada and in other countries. Since these projects were financed by the concerned mining companies, all results remain confidential unless we obtain permission to publish. Three companies have graciously allowed us to use their information which I will describe in this text. These are the Polkowice copper mine in Poland, the North Coast Industries ltd graphite deposit and a talc company which preferred to remain anonymous. I will also describe our 2 inch column which was used for all tests. Data is also given on how to scale-up the 2 inch column to industrial size.Figure 1 presents a schematic of a flotation column. Feed, at a controlled rate and pulp density, enters at about 1/4 of the height of the column from the top. A controlled rate of air is bubbled into the bottom of column through a fine-holed sparger. The column volume between the feed point and the top of the sparger is called the recovery zone. Tailings, at a controlled rate, always slightly greater than the feed rate, discharges from the bottom of the column. This difference in feed and tailings flowrates is called the bias. The floated mineral is carried through the recovery zone on air bubbles which rise into the cleaning zone which is that column volume between the feed point and the overflow at the top. As the bubbles rise in this zone they are washed of gangue material by wash water which enters over the top of the froth layer. The froth layer is maintained at a given depth during flotation but this depth will depend on the froth cleanliness, for quite a bit of cleaning by wash water is accomplished in this layer."

Jan 1, 1988

By I. Tinto

"IntroductionEnvironmental pollution problems, caused by gases or effluents, by high noise levels or from air borne dust, are placing increasing demands of the operators, from statutory authorities, and from the general public, to adopt more stringent dust control measures. This requires that a successful plant dust control program be an integral part of any plant operation. While a successful environmental program is a key factor in maintaining productivity and good labour relations, anticipation of future environmental regulations during the plant design phase can avoid the high cost of plant upgrading, or dealing with pulmonary conditions in the work force in subsequent years.Particulate removal, conventionally called dust collection, involves the removal of coarse- and fine-particulates from the airstream. Although generally limited to that required for contro!Hng plant generated air emissions, particulate control equipment also has a wide application for air cleaning and filtration inside the plant, as well as for recovery of usable products.In the late 1950s and early 1960s the public became more concerned with the problems of air pollution. This increasing concern was stirred by an awareness of the extremes to which water pollution had progressed in many of the rivers and lakes, by increasing perception of air pollution as detected by visible smog and harsh chemical odors, by the alarming rate of increase of smog plagued cities and communities, and by specific incidents where ill health could be traced to specific episodes of air pollution. Particle size is perhaps the most important single factor affecting particulate control. Large particles (over 5 microns) constitute the major mass fraction of most sources of emission and economical control equipment dqes exist for their efficient control. However, while these larger particles frequently represent the source of soiling and unsightly smoke plumes, they are not a major health problem as they tend to settle relatively quickly, are more easily scrubbed from the atmosphere by rain, and are not able to penetrate the respiratory system. By far the most important form of particulate air pollution is the fine particulate, (below 3 microns) which is harmful to the pulmonary system. The adverse effects caused by this particulate matter on human health are for the most part related to injury to the surfaces of the respiratory system. Particulate material in the respiratory tract may produce injury itself, or it may act in conjunction with gases, altering their sites or their modes of action. A combination of particulates and gases may produce an effect that is greater than the sum of the effects caused by either individually (i.e. synergistic effect)."

Jan 1, 1989

By W. A. Roliff

The renewed interest of the past few years in the Appalachian and Michigan oil provinces has not, as yet, created any marked increase in activity in Southwestern Ontario. During 1960 development drilling in-creased somewhat over 1959, but exploratory drilling decreased slightly. More attention was devoted to the deeper horizons, but lake drilling de-creased considerably. Oil production reached a new peak and gas production increased slightly. During 1960 an interesting oil and gas discovery was made in the Cambrian and gas discoveries six miles off-shore in the eastern part of Lake Erie were made in the Clinton-Cataract zone of the Silurian. This paper reviews activities during 1960, summarizes the discoveries made to-date and the pertinent exploration data relating to the prospects of the region and discusses some of the economic aspects of exploration and development. D URING the last few years there has •been a marked renewal of interest in the old petroleum

Jan 1, 1961

By Roger J. Berdusco

Kaiser Resources Ltd. owns and operates a 5-million-tonper- year open-pit and hydraulic coal mine near Sparwood in southeastern British Columbia. Since 1969, Kaiser has maintained a field-scale reclamation program dedicated to the reclamation of disturbances associated with past and present mining and exploration activities . Since that time, over 1400 acres have been treated using modified forestry and agricultural techniques with encouraging results.

Jan 1, 1978

By Jerry Ran

Many large underground mines using the open stoping method have changed their primary applications of consolidated rock fill (CRF) to paste or consolidated hydraulic fill due to considerations of demand in infrastructure and equipment, system reliability, backfill capacity and material sources. However, some smaller or even large mines still use or consider using CRF for backfill purpose due to factors such as capital expenditure, availability or suitability of other fill types or in some cases local regulatory requirements. As demands on CRF applications diminish among major mining companies, there is a lack of recent literature on application of CRF to open stoping in design and operation. There are several methods being used for fill strength design. Results from these methods have been successfully applied to paste or hydraulic fill. However, the design strength for CRF is much higher than that determined by use of these widely accepted methods. In operation, CRF preparation and placement have significant impacts on the quality of placed CRF and therefore the mining performance. This paper reviews the current fill design methods and their applications to open stoping with presentation of the bench marking data, presents fill failure cases and various CRF preparation and placement arrangements and discusses quality assurance and control programs.

Jun 1, 2012

By P .. H. Grimley, N. Champigny

"Fourteen companies (Appendix) representing senior mining organizations in Canada were canvassed in order to assess: (1) the current usage and trends, and (2) the usefulness of computer applications in ore reserve estimation and grade control. The results of the questionnaire suggest that:• computers are unsurprisingly, predominant in the mining industry for calculating reserves and performing grade control;• time and cost savings are realized;• computer-based approaches are applicable to underground situations;• geological information is incorporated to the computerization process; and• computer usage does not hinder the collaboration of geologist and mining engineer.A clear need is identified for case histories comparing computer-calculated ore reserves and actual production data.IntroductionAmong the management and technical staff of some mining companies there is a perception that the application of computer based technology for the estimation of ore reserves and grade control, has as many drawbacks as benefits. Some of the objections raised against the utilization of computers for ore reserve estimation are that:• computer-based reserve models work for large open pit mines but not for underground situations;• computer-generated reserves ignore the geologist's knowledge base; they are strictly a number crunching exercise; and• the use of computers for ore reserves hinders collaboration between the geologist and mining engineer.In order to determine (I) the extent of current computer usage and future trends and (2) whether the objections noted above are borne out by experience, a number of senior Canadian mining companies were canvassed.The respondents were asked to provide:• an assessment of the importance of the computer in the ore reserve estimation and grade control process;• the level of involvement of individuals and staff groups with computer-based ore reserve estimation;• the advantages perceived and realized from the utilization of computer-based ore reserve approaches;• the current and future human resources requirements for the evaluation, implementation, maintenance and development of computer-based ore reserve systems;• the hardware and software resources presently used and planned; and• the developments needed to increase the use and acceptance of computer-based ore reserves."

Jan 1, 1990

By G. Tairova, M. Murchie, B. Esford, E. Lam

"The objective of this project is to investigate methods to lower the sulphate concentrations in the mill effluent. Currently, the concentration of sulphate in mill effluent is approximately 2 g/L. The high concentration of sulphate ion in the effluent has the potential to become a regulatory issue. The target sulphate concentration in mill effluent for this work was less than 500 mg/L. The pilot studies, using sulphate precipitation, were carried out at the mill. The results of the sulphate precipitation pilot study, using calcium hydroxide and sodium aluminate, indicated that:• The sulphate concentrations in effluent could be reduced to less than 500 mg/L.• The concentrations of most other elements of concern, such as selenium, arsenic, cobalt, nickel and vanadium, were also reduced.INTRODUCTIONHistorically, the concentration of sulphate, SO4 2-, in water has not generally been subject to regulation. However, with the increasing global consumption of water, stricter regulations on sulphate quantity may be imposed. Sulphate is a concern in process waters as it forms scale on process equipment and leads to operational problems. High sulphate concentrations may result in adverse health effects. The taste theshhold for the most sulphate salts in drinking water ranges from 250 to 500 mg/L.A literature search and review to identify methods to reduce sulphate concentration in the mill effluent was carried out. A number of methods were selected and tested in the lab. The experimental results indicated that the precipitation methods, using calcium hydroxide and aluminum compounds, barium compounds, as well as the ion exchange and the membrane methods, were effective for the removal of sulphate to below the required limits. Some other elements, such as vanadium, nickel, cobalt, selenium and molybdenum, were also removed.The process, using calcium hydroxide and aluminum compound for sulphate precipitation, similar to the Cost Effective Sulphate Removal (CESR), also known as “Walhalla” process, described in the Montana Tech report (“Demonstration Of Sulfate Removal” 1999), was selected for further consideration [1]. In the CESR process, the water is treated with lime for precipitation of gypsum, followed by the reaction with a proprietary aluminum compound for removal of a residual sulphate. The final pH adjustment is carried out using carbon dioxide. Results of a preliminary cost estimate indicated that the removal of sulphate using calcium hydroxide and aluminum compound was the preferred method of treatment, considering its low cost, availability of chemicals and minimal changes to the existing plant circuit."

Jan 1, 2012

By Wang Wenqian, George W. Poling

"Devices and flowsheets for recovering fine placer gold are reviewed. Inefficiencies of gravity processing techniques are documented and discussed. Prospects of combining gravity and froth flotation techniques are presented. Possibilities of using other separation techniques, such as magnetic and electrostatic devices are also discussed.IntroductionSeveral new methods for beneficiating different types of placer ores have been developed in the last two decades. Improved efficiencies in the recovery of fine particles have been achieved by improving gravity flowsheets and machines as well as by developing multiple treatment techniques involving flotation, magnetic and electrostatic separations. Placer gold processing, however, has been an exception to some extent. Gravity concentration using riffled sluices accompanied by mercury amalgamation is still the main method in use today. Because of this, the recoveries of fine gold and the other associated values are often similar to those achieved several decades ago. For example, very few sluice systems recover significant placer gold finer than 100µm in size.Only a few proposals for using alternatives to simple gravity methods for recovering fine placer gold can be found in the published literature. The fixed, low gold price discouraged research in this field for many years. Development of more efficient processes has not kept pace with the recent rapid escalation in the price of gold. Froth flotation for saving fine placer gold might now prove economic, for example. This paper reviews literature published on the recovery of fine placer gold over the period 1907 to 1980. Suggestions for improving the performance in this field, based on the authors' current testwork, are also presented."

Jan 1, 1983

By Jae-Chun Lee, Rajiv Ranjan Srivastava, Min-seuk Kim, Byung-Su Kim

Recycling of spent hydrotreating catalysts (HTC) can potentially contribute towards the sustainable extraction of metal values. Treating such materials by hydrometallurgical methods to separate metals from the leach liquor of either acid/alkali media is a major step. In the present study, separation of molybdenum from HCl leach liquor of spent NiMo type HTC has been investigated by applying solvent extraction using Cyanex-923. For this, the chloride solution containing 973 mg/L Mo, 254 mg/L Ni and 1634 mg/L Al was taken as the aqueous feed. The parameters including contact time, concentration of the extractant, acid and chloride, and phase ratio were varied to investigate their effect on the extraction efficiency. The McCabe-Thiele plot suggests that > 99% Mo-loading using a 2-stage extraction process. From the molybdenum depleted solution, nickel was selectively extracted by Cyanex-301 leaving Al in the raffinate.

Jan 1, 2014

By R. S. Jones

"Fording Coal Ltd. is now in its fifth year of a 15-year contract to supply 3 million long tons of clean coal per annum to its Japanese steel-making customers. The mine employs both conventional truck-shovel and unconventional ""walking"" dragline coal mining techniques in multiple-seam pits. This paper describes the present and future application of the 60-cu.-yd dragline and truck-shovel pre-stripping fleet in 1•ecovering 5- to 40-footthick coal seams in mountainous terrain. Deep blastholes, coal flow demands, spring ""run-off"", seam and inter-seam thrust faulting, limited seam outcrop data and regional faulting are a few of the problems encountered in this application. The author discusses these problems and their solutions as applied at Fording Coal Ltd."

Jan 1, 1976

By I. Haskett

ABSTRACT The Redwater pool, in north-central Alberta, was discovered in October, 1948, and at the end of 1950 was about 85 per cent developed. Production is from a Devonian coral limestone reef and is found at an average depth of 3,150 feet. The pool has an estimated .productive area of 37,000 acres, and a maximum oil zone thickness of slightly over 200 feet. Wide variations exist in both type and values of porosity, with the average value determined for the reservoir being 6.16 per cent. The total stock tank oil in place is about 1.24 billion barrels. The crude has a saturation pressure of 485 psig, com-pared to the original value of 1,050 psig for the reservoir, and the principal recovery mechanism so far has been the natural water drive. Cumulative production to January 1st, 1951, has been about 15.5 million barrels. These withdrawals resulted in a reservoir pressure decline of slightly over 100 psi. Predictions of future behaviour indicate that the water drive will not be of sufficient magnitude to maintain the reservoir above saturation pressure past 1953, and that, with natural depletion, the pool will be produced largely by a solution gas drive. Pressure maintenance by water injection has been considered and the possibility of raising the pressure to the original value of 1,050 psig is also discussed. INTRODUCTION WITH the discovery of the Lewduc pool, early in 1947, the Devonian limestone became the major geological formation contributing to Western Canada's rapidly growing petroleum reserves. Redwater, discovered in October, 1948, is now the largest known Devonian pool in Canada, with a recoverable reserve estimated at approximately 500 million barrels. Until recent years, the knowledge of the nature and characteristics of this type of limestone reservoir has been comparatively limited.

Jan 1, 1951

By J. D. Bateman

Introduction The lifting of restrictions on the development of radioactive mineral deposits by private individuals has re-opened the search for uranium in Canada to a large body of professionally trained prospectors. The entry of private capital and experienced prospecting techniques into the search for radioactive minerals has been enormously stimulated by the atomic developments of the past several years; and we can now look forward to the discovery of new productive sources of uranium. The rate of new discoveries will, how ?ever, depend on the effectiveness of the methods used. The large number of new pitchblende occurrences reported within the past several months is largely a measure of the energy with which the portable Geiger-Müller counter has been applied in the field. The counter is simply a 'radio' receiver tuned to one of the products of spontaneous atomic disintegration that is characteristic of all radioactive materials. Its effective use depends largely on how it is applied under the various geological and topographical conditions that ma y be encountered, and also on an understanding of its limitations. Extensive geological information relating to the occurrence of radioactive minerals in Canada has been accumulated during the past several years, and it is now possible to define in a general way many of the geological formations in which pitchblende and related minerals are likely to occur. Furthermore, prospecting can be localized in those parts of the favourable formations that offer the greater promise of containing commercial deposits. In this selection, the Geiger counter is the most useful tool available to the prospector for the actual detection of radioactive materials. As an example, an area of two square miles in the Northwest Territories, within which about a dozen pitchblende occurrences had been found over a several year period by conventional prospecting methods, yielded more than forty-five additional discoveries by application of the Geiger counter. Yet earlier attempts at prospecting this area with the counter had failed, due largely to faulty instruments and lack of experience in field application. The limitations of the counter are very considerable; but, when they are recognized, there is no more useful tool for the discovery of radioactive ores. It was not until 1944 that a practicable portable counter was developed, and then only by co-operation in the field by geologists and physicists. Officers of the Geological Survey of Canada working with physicists of the National Research Council brought about the development of the modern counter.

Jan 1, 1949

By P. J. Noakes

Remote and isolated, located in a frigid, hostile environment, the Black Angel mine in Greenland had to create a warm social environment which would help attract and retain a stable work force of miners and support staff. The high cost of personnel turnover plagues many mines and, when the mine is inside the Arctic Circle, accessible by helicopters which are highly vulnerable to unpredictable weather conditions during the long, dark winters, the potential costs of personnel turnover become critical factors in the success or failure of the mining venture. Manpower planning should start from the date the engineers begin the technical design of the new mine. The plan should include provisions not only to ensure an adequate, skilled work force, but also to ensure a stable work force of people who are happy enough in the mining environment to want to remain, take their vacation and return to work at the mine. The skilled work force was assured with training courses of four months, designed to produce highly specialized underground workers from unskilled Danes and Greenlanders supported by trained Swedish and other Scandinavian miners. The stable social unit was assured by plans the primary attribute of which had to be flexibility. The accommodation changed from shared accommodation with communal washroom facilities to single accommodation with private washroom facilities. A recreational director was hired to help the workers make use of elaborate recreational facilities. A closed-circuit TV and radio system was installed to operate as a private broadcasting system using taped programs originally broadcast on European TV networks or developed by the mine personnel themselves. The liquor rules were changed and the mine manager became a licensed innkeeper responsible for the orderly operation of the Black Angel Bar in accordance with the Danish laws governing the services of a public bar. The result is a relatively stable work force. Some 35% of the people have more than two years' service with the company, Greenex A/S, and some 62% complete 10 months of service.

Jan 1, 1978

By J. W. Hohn

The precipitation of Fe(III) to form ferrihydrite in the presence of arsenic is the United States EPA's Best Demonstrated Available Technology for treating arsenic-containing hydrometallurgical solutions and waste streams. This technology has been widely adopted throughout the world and developments have been well reviewed. The adsorption and long-term stability of ferrihydrite can be improved by co-precipitating Fe(III) and Al(III) together to form an aluminum-modified ferrihydrite. Arsenate adsorption into ferrihydrite and modified ferrihydrite as a function of pH, Fe/As or (Al+Fe)/As mole ratio, and the initial As(V) concentration is presented and compared. The results of long-term aging of both adsorbents at 70°C for over a year are also summarized.

Jan 1, 2006