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By F. McGravie, S. T. Solinski, W. W. Robertson

During this, the Centennial year of the discovery of the Hall-Heroult process, it seems appropriate to review some of the developments which have taken place in Canada and to explain why it has become an important world centre for the production of primary aluminum. For many years after it was recognized that the element aluminum existed, scientists were frustrated in their efforts to isolate it. In the early 1800s H. C. Oersted and Frederick Woehler prepared small quantities sufficient to measure some of the physical properties. A quasi-commercial process involving reduction with metallic sodium was developed by the French scientist H. St. Claire Deville in 1855 but the cost was very high ($30. 00 per kg). It was not until 1886 that Charles Martin Hall in the United States and P.L.T. Heroult in France, more or less simultaneously but completely independently, discovered the process which is essentially that in use today. Some of the early pioneers in the industry quickly recognized the potential of the hydro-electric resources in Canada as economic energy suppliers for aluminum production. The first commercial production in Canada was in Shawinigan, Quebec in 1901, only 15 years after the process was discovered. Subsequently operating plants were established at nine different locations in Canada (Quebec and British Columbia) (Table 1). Operations continue today in all locations except one (La Tuque). The table shows present plant capacity which for the older plants was reached in an evolutionary manner including replacement of obsolete capacity or upgrading and modernization of existing designs.

Jan 1, 1999

By Pierre Sauvé, Alex Makila

"The Camflo stock of porphyritic quartz syenite is an irregular pipe-like body 200 metres in diameter injected along the axial plane of an E-W trending F2 fold, near the contact between the. Kewagama and Malartic groups. The stock plunges 55° to the NE, almost parallel to the fold axis. The stock, exhibiting pervasive, weak cataclasis with numerous, locally auriferous quartz veinlets, is cut by minor faults striking WNW and dipping about 45°NE.Two types of gold ore are distinguished at Camflo: ""porphyry"" ore and ""fault zone"" ore. ""Porphyry"" ore, accounting for 90% of the gold produced, forms wide zones within the stock. The zones are irregular in shape but tend to be oriented E-W in plan view (on a horizontal plane) and are elongated paraliel to the plunge of the stock. These zones are more abundant in the northern part of the stock. Differences between ore and barren porphyry are not obvious. ""Fault zone"" ore occurs outside the stock along minor faults, particularly in differentiated sills offer rodiorite and felsic granophyre. Gold grade is roughly proportional to the pyrite content which in turns depends in part on the original magnetite content of the host rock. Although both types of ore show some correlation between Au and S, the Au/S ratio is considerably higher in porphyry ore.The bulk of the gold is in quartz syenite and in felsic granophyre, the most brittle lithologies at the mine. Presumably, the vertically continuous, pipe-like stock, made up of shattered rock, provided the main channelway for the ascending mineralizing solutions."

Jan 1, 1990

By Serena Biella

Gold has received a growing interest as a catalyst for the selective oxidation of organic molecules using oxygen under mild conditions1. In the liquid phase application small gold particles (2.5-7 nm) deposited over different solid supports can be used but, like many other noble metals, their catalytic activity depends upon the nature of the support and the preparation metod2-5. In particular, gold on carbon is the preferred catalyst for the oxidation of the alcoholic 2-7 and the aldehydic7-9 groups and one of the best preparation method is the immobilisation of colloidal particles2-5,8,9. Suggested application of gold catalysis in fine chemicals production, tested on laboratory scale preparations, is reported in table 110. In order to produce more efficient catalysts for the liquid phase oxidation and to derive new insights into the reaction mechanism, we have made a comparison among catalytic systems based on different metals. The first effort was to test the activity, if present, of naked metal particles and then to study the influence of various materials commonly used as a support.

Oct 1, 2003

By H. Hejny

Economy needs mineral raw materials in almost each sector of modern life. They can only be provided by mining activities. An increasing share of the total mining production will be by underground mining. The mineral deposits will be found at gradually greater depths, including all problems associated with them. It involves an increase in overburden pressure with subsequent rock stability problems and risks of structural collapse. There is a need for new and safe technologies for almost all parts of a modern mine. The mining industry faces a number of challenges which require technical solutions that encompass the entire network and include the economic, social and environmental issues. The industry needs a new image based on pioneering solutions and a modern structure that can exploit minerals at greater depths and promote both high productivity and safe working conditions. Funding has been secured from the European Commission for the I²Mine project. Work started in November, 2011. This initiative is designed to focus on the technological challenges that the mining industry is currently facing including the exploitation of ever deeper deposits and the aspiration for an invisible, safe, zero impact mine. The project comprises a consortium of 27 organisations from 10 European countries. I²Mine marks the start of a series of development activities aimed at realising the concept of an invisible, zero impact, deep mine. The extractive sector, still seen as being old fashioned and environmentally unfriendly, will show that mineral extraction and processing can be done in a highly innovative and sustainable manner with low impact underground and zero impact above ground. The concept of I²Mine is to develop innovative methods, technologies, machines and equipment necessary for the efficient exploitation of minerals and disposal of waste, all of which will be carried out underground. This will dramatically reduce the volume of surface transportation of both minerals and waste, minimising above ground installations and reducing the environmental impact. New eco-efficient technologies will be applied in order to make the entire mining process more efficient and environmentally sound. The concept is for an integrated mine, with the majority of the installations underground, and only the final product will be transported above ground to be shipped to the customer. Production waste will be treated and stored underground and gaseous emissions will be managed underground as far as practical. I²Mine will also focus on ideas and concepts that increase energy efficiency and decrease waste. The core of the project will be to develop breakthrough technologies for autonomous, highly selective, continuous mineral extraction processes and machinery based on new sensor technologies, face front separation as well as innovative concepts for mass flow management and transportation integrating state of the art technologies. The concept of an invisible, zero impact mine requires a refined process underground that selectively extracts the mineral thereby reducing waste. For this reason, improved extraction machines and near to face processing methods, including backfill procedures, need to be developed. These developments include rock mechanics and ground control solutions, incorporating health, safety and environmental issues.

Aug 1, 2013

By T. Feldmann, G. P. Demopoulos

The feasibility of chloride leaching processes depends on interfacing them with cost-effective HCl regeneration technologies. This paper summarizes the most important findings of research conducted in the past 3 years concerned with a novel process to regenerate high-strength HCl from concentrated CaCl2 solutions at temperatures below 100°C, via reaction of CaCl2 with H2SO4 resulting in the formation of calcium sulfate phases (gypsum, a-hemihydrate or anhydrite). From constant supersaturation semi-batch experiments in pure solution it was found that the crystal growth rate of hemihydrate, and hence the particle size, was influenced by the rate of reagent (Ca2+, SO4 2-) supply to the reactor. Additionally, growth studies of DH in presence of impurities (K+, Mg2+, Sr2+, Ba2+, Fe2+/3+, Al3+, La3+, Y3+, F- and PO4 3-) showed that specifically Sr2+ and PO4 3- are taken up during crystal growth. Furthermore, it was found that decreasing water activity (via different HCl/CaCl2 concentrations) and increasing temperature reduce the metastable life-time of DH and HH by increasing the phase transformation speed. The DH/HH transformation was identified to be dissolution-precipitation based, while HH to AH is a topochemical process. Finally, continuous experiments on bench scale are underway to confirm the feasibility of the process to obtain super-azeotropic strength HCl with up to 9 mol/L (~30wt.%) from 5 mol/L CaCl2 (~40wt.%) solution.

Jan 1, 2014

By J. Güntner

A significant portion of Outotec's business relates to the application of fluidized bed for processing a wide range of industrial materials, including gold ore and gold concentrate. As part of the former Lurgi and Boliden organization, our division constructed the first industrial reactor for roasting sulphur-bearing materials in 1950, based on the principles of fluidized bed technology. This process, when combined with efficient heat recovery and off-gas treatment and its conversion to sulphuric acid, became the standard for processing sulphur-bearing ores. In the last 60 years we have delivered more than 265 plants and developed (in addition to the standard fluidized bed solution) variants of the fluidization technology, such as the circulating fluidized bed and the bubbling fluidized bed. This paper describes the different options of the fluidized bed technology for gold roasting reflecting on main process design criteria.

Jan 1, 2011

By W. G. Spencer, E. Sulis, P. M. Tiley

"Dome Mine's No.8 shaft is located about 1 km northeast of Dome's No.3 shaft and mill complex in South Porcupine, Ontario.No.8 shaft was brought into production in 1984 to hoist ore and waste for the complete mine as well as to service the mine from the 1600 level and below. Access above 1600 level is provided by No. 3 shaft.The rectangular shaft has six compartments consisting of two skips, a cage, counterweight, manway, and a service compartment. The over-all size of the shaft is 14 ft 7 in. by 20 ft by 7 in. (Fig. 1). A 7th compartment for shaft deepening is incorporated in the bottom 500 ft of shaft. The shaft is 5470 ft deep. The loading pocket is located at 5300 ft and the dump 61 ft below the collar.Surface facilities consist of a concrete headframe and a structural steel hoistroom which houses the cage and production hoists . The service hoist is a 12-ft diameter double drum, with one 1750 HP DC motor, and the production hoist is a 15-ft diameter double drum with twin 1750 HP DC motors.Both hoists have a single clutch and a single reduction gear train built by Orenstein & Koppel, and equipped with Canadian General Electric drives. The cage hoist is equipped with a disc pinion brake.The skips were originally aluminum 14-ton capacity, Rolla-chute design with steel liners on three sides and 4 in. of rubber on the back, to absorb the loading impact. The original guide rollers consisted of fixed 10 in. pneumatic tires. The face-to-face units were eventually replaced with larger airplane-type tires mounted on a spring loaded pivot arm."

Jan 1, 1993

By R. H. Chambers, L. Alderman

"The paper is introduced by an examination of the factors which have led to the present world-wide interest in charging preheated coal to coke ovens. Various possible methods of preheating and charging the coal are considered and reasons are given for the adoption of the methods chosen. The design of the pilot preheating plant for the British Coke Research Association is discussed and its influence on the design of the commercial units for the South African Iron and Steel Corporation's plant at Pretoria and the British Steel Corporation's plant at Beighton are explained. Operating procedures on the pilot plant are described, particularly with regard to the charging of the preheated coal. Design features of the commercial installations, engineered by Simon-Carves Ltd., are explained with emphasis on the built-in safety of the control system of the preheating plant, and the particular problems associated with the erection of such plants on working coke oven batteries. Commissioning and operating procedures are described and the problems associated with the integration of the preheating plant into the normal pushing schedule of the plant are discussed. Preliminary operating results with regard to the effect of preheating on coal throughput on the commercial plants and on the properties of the coke produced are given."

Jan 1, 1972

By A. A. Brant

Self-potential methods are based ?on measurements on the surface of voltage distributions caused by natural sub-surface oxidation phenomena. The attempt is made to. correlate voltage minima or maxima with the location of mineral materials or geological conditions which may give rise to such naturally produced spontaneous potentials. Any orebody undergoing oxidation is a source of electric current. Ground waters carrying free oxygen attack the upper surface of the body, rendering this the positive pole of a galvanic cell, with the lower portion of the body the negative pole and the surrounding weak acidic waters the electrolyte. Current flow is from positive to negative through the orebody and negative to positive through the electrolyte, i.e., through the surrounding rock. The upper end of a steeply dipping, tabular orebody is hence indicated as lying below the point on the surface where the largest negative potential is observed(l). From its basis, it is apparent that the self-potential method was developed primarily for ore exploration.

Jan 1, 1942

By A S. Leitch

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

Jan 1, 1964

By Tom Demorest

SMART is an association of mining companies that meet regularly to coordinate the technology development needed by the mining industry. Since 1995, the member companies and institutions have directed research and influenced the manufacturers and suppliers to improve surface mining technology and services. SMART actively supports learning seminars, collaborative research projects, and user groups. Members of SMART include some of the major surface mining companies in North America and Australia. These companies have recognized the value that collaboration can bring to the needs of individual organizations as well as the global mining industry.

May 1, 2009

By G. Goodlad

This paper describes some of the main aspects involved in implementing the European “Equipment and Protective Systems for Use in Potentially Explosive Atmospheres” (ATEX) Directive (No.94/9/EC) in the British mining industry by the year 2003. It provides a brief background to the Directive and considers its main objective of removing all barriers to trade in Europe. It outlines the need for the European Standards making bodies to write new editions of the ’explosion protection concept standards’ and for manufacturers to adopt new quality management procedures and develop new versions of equipment in conformity with the ATEX categories of “M1” or “M2.” Finally, it assesses the possible future relationship between the European enforcing authorities, manufacturers and users of explosion protected equipment.

Jan 1, 1999

By G. S. Hume

FOR MANY YEARS Canada lived in the hope of attaining a substantial production of petroleum and natural gas that, to geologists familiar with the sedimentary basins of this country, seemed an entirely reasonable expectation. There have been surges of exploration activity stimulated by oil and gas discoveries and development such as occurred in Turner Valley. However, it was not until the Leduc field in Alberta was found in 1947, and the significance of that discovery was realized, that the search became really intensive and continuons. Expansion now has become a matter-of-fact attitude based on results which would have been considered impossible of achievement a few years ago.

Jan 1, 1957

By E. M. De Souza, A. M. Coode

"When Canadian potash was brought into production in the 1960s substantial research was carried out to develop the technology needed to cope with the unique conditions in Saskatchewan mines. The intense research has established Saskatchewan's position as a leader in production technology on a world scale, and as a leader in setting international standards for potash production. The industry is now more than two decades old and, although the mines operate efficiently, there are a number oj prominent areas of concern. High among these is the prediction, prevention and control of sodium rich brine inflows. Control has proven difficult or elusive in the potash mining horizon, but work continues in this area. Control of brine in the superincumbent limestone formation has proven to be easier and more conclusive.The first part of this paper describes the rehabiltation, diamond drilling, and grouting completed at Central Canada Potash, which reduced the brine inflow from approximately 82 l/min . at the beginning of the work to O.9/1min. when the backfilling was placed.The second part of the paper describes the rationale for choosing the rock mechanical instrumentation, the reasons for their placement and the rock mechanical data recorded with some interpretation.IntroductionCentral Canada Potash is located approximately76 km southeast of Saskatoon, near the Yellowhead Highway. The commercial production of potash at CCP started at the end of 1969 at a depth of 1021m below surface. The potash zone, which is presently mined, is approximately 3.35 m thick . Stress relief methods using yielding pillars are used in the design of the mining layouts. The planned extraction ratio averages 35070 . The mine is designed to produce approximately 3.3 million tonnes of sylvinite per year to give approximately 1.3 million tonnes of finished product (muriate of potassium) per year."

Jan 1, 1990

By R. R. Tatiya

"The ultimate aim of a mine design is to determine the development work involved and resources required by adopting one or more specific alternatives. A part of the process is the production of mining plans/designs, an outline of the amount of work and costs involved as well as a prediction of the revenues expected. The paper aims to examine these aspects of mine design using the computer models developed. These models are capable of designing and performing economic analysis for one or more stopes for a continuous orebody. IntroductionTatiya and Allen (1987) have described ’defining stope boundaries using a computer.’ Using the stope boundaries defined or even hypothetical ones, algorithms have been prepared to design the layouts of the following stoping methods: 1. sublevel stoping (longitudinal as well as transverse);2. DTH (Down-the-hole) stoping; and3. flat back cut and fill stoping with posts and pillars.Tatiya (1989) presented this work at the 21st symposium on the application of computers and operations research in the mineral industry (APCOM). Economic analysis of a stope is the additional feature incorporated with these algorithms.The system has been tested by an economic analysis of the three stoping methods modeled for a small portion of a deposit of a copper mining complex. The deposits at this mining complex form lenses of varying shapes and sizes, having low copper content. These chalcopyrite lenses are steeply inclined with a thickness in the range of 5 m to 60 m. The strata are competent and suitable for underground mining.In different sections of the mines different sets of equipment are used to perform the basic unit operations. Some of the ore handling levels in the mines are trackless, the rest are tracked."

Jan 1, 1998

"Eastern Canadian thermal coal mined at Minto, New Brunswick, and in western Cape Breton at St. Rose, Inverness County, Nova Scotia, contains 6-8 per cent sulphur. Both coals are high volatile bituminous. types. The Minto coal averages 18 per cent ash, 7 per cent sulphur and has a Btu rating of 11,900 per lb. Pyritic sulphur accounts for 75 per cent of the total sulphur and the remainder is largely organic; the amount of sulphate sulphur is negligible. This means that in a 7 per cent sulphur coal, 2 per cent is organic and 5 per cent pyritic sulphur. Pit-head St. Rose coal contains approximately 10 per cent ash, 7 per cent sulphur and 11 ,800 Btu/lb. The distribution of sulphur is different to that of Minto coal because about 12 per cent sulphate sulphur is present. Thus, a 7 per cent sulphur coal would contain 4 per cent pyritic, 2 per cent organic and 1 per cent sulphate sulphur.The iron sulphides, pyrite and, to a lesser extent, marcassite occur over a wide size range from large sulphur balls to crack fillings, lenses, and individual crystals and framboids. Coarse-grained pyrite and sulphur balls are easily separated during washing. It is the fine grain sizes, intimately mixed with the coal constituents, that are difficult to separate. Quantimet analyses of the fine grains in coal from both localities showed that about 50 per cent were smaller than 30 micron(1).No efforts have been made to wash the Inverness coal of Nova Scotia and in 1980 washing ceased in New Brunswick. Previously, the Minto coal was processed in an antiquated jig circuit which reduced ash from the strip operation run-of-mine value of more than 20 per cent to less than 18. More effective removal of ash and sulphur could clearly be obtained. Laboratory tests on both Minto and St. Rose coal have shown that ash rejection rates of 40 to 50 per cent at yields of 70-80 per cent were possible(2), Little information on sulphur removal was available."

Jan 1, 1981

On the recent trip from Vancouver to Calgary with the President, Mr. C. C. Huston, and yourself, I had the opportunity of outlining a plan based on the following: Among the aims of the Institute are, obviously, the fostering of the confraternity of those engaged in the technical and management fields of the mining and petroleum industries. This may be achieved in a number of ways, of which, to me, the interchange of ideas and experience between different parts of Canada and different sections and divisions of the Institute appears to be one of the most important. I think you and the membership as a whole are, and have been, well aware of this. The annual tour of the President .and Secretary, particularly their visits to Branches, shows this to be true. The interchange of ideas through the medium of the BULLETIN also illustrates the point; indeed, most Institute activities are directed along these lines. I am convinced that much more could be accomplished if it became financially possible to do so. Many able and fine men are, I think, willing and anxious to give their time and energy to furthering these phases of Institute activity, but it is unfair to expect them to assume as well the financial obligations involved. Specifically, I would suggest that the following could be done if sufficient funds were available:

Jan 1, 1952

By Larry A. Morris

The environmental impacts of industrial activities have become very serious concerns of the public over the past few decades. Not surprisingly, governments have responded with legislation and regulations to force industry to operate in a more environmentally responsible manner and, more recently, have prompted industry to initiate voluntary measures in response to specific environmental issues. The concept of Product Stewardship has evolved as a system or vehicle for the industrial sector to demonstrate an active concern about the environmental impact of their products, services and processes.

Jan 1, 1996

Iron deposits of every major type except laterite occur in Quebec, and form one of the major iron ore resources of the world. The five principal types of ore described are: (1) hematite-goethite masses derived from iron formation through the oxidation and enrichment of iron by natural processes; (2) taconites consisting of fine-grained iron formation; (3) metataconites composed of coarse-grained iron formation; (4) iron and titanium oxide minerals in massive or disseminateed deposits within gabbro and anorthositic rocks; and (5) replacement or contact? metasomatic magnetite deposits associated with complex silicate and skarn mineral assemblages. Most of the ore, although relatively low grade, is easy to concentrate. The physical properties of the ores that affect the choice and efficiency of beneficiation methods are described. The extent to which iron ore from this area can be utilized in the future will depend on the continued use and improvement of highly efficient methods of beneficiation.

Jan 1, 1964

By Robert B. Parsons

"While it might seem like heresy to suggest that ""taxation"" can be a source of financing, never the less some generous tax rules can considerably enhance the tax savings pertaining to a particular expenditure or project. A basic tax knowledge, and careful tax planning, can optimize government participation in a project. INTRODUCTIONIn trying to identify sources of financing for a project, ""government"" as a source of funding is normally thought of in terms of government grants, loan guarantees, interest rate buy downs, property tax waivers, hydro subsidies, and so on. Generally, such concessions are somewhat difficult to obtain, especially in the current period of apparent fiscal restraint. One source of government funding which should not be overlooked is the income tax regime, and, at the provincial level, the various provincial mining tax regimes.While the taxpayer would not normally view a tax system as a potential source of government financing, nevertheless various federal and provincial rules applicable to the mining industry can offer attractive tax deductions - and tax savings - with respect to particular expenditures. In fact, it is not unusual for a civil servant to refer to a tax deduction as a tax ""subsidy"". For example, in the right circumstances, the cost of a smelter expansion in New Brunswick would cost the operator only 31 cents on the dollar, with the federal and provincial governments paying for the other 69 cents by foregoing tax revenues (Table I). In a sense, such tax savings could be compared to a government grant equal to 69% of project costs. Of course, not every project expenditure will generate that degree of government funding. The fact of the matter is that the percentages of tax savings attached to different expenditures cover a wide range, depending on a complex mix of factors. The point to understand is that the tax rules can offer some valuable savings, even after tax reform, and that a basic knowledge of the tax rules can yield some fruitful rewards."

Jan 1, 1989