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By C. Allen

In 2004, Boliden Odda underwent an extensive modernisation project targeting mainly the leaching section of the plant. Direct leach technology was introduced as part of this project. The Direct Leach process, developed by Outokumpu, is an atmospheric oxidative leach of zinc sulphide concentrate. The effects of this new processing operation on behaviour of iron in the plant are discussed. As well, the filterability of the new residue on belt filters prior to its deposition in mountain caverns is also discussed. The solids from the direct leach process have been analysed by scanning electron microscopy, and the results of these analyses are presented.

Jan 1, 2006

By H. R. Banks

SHORTLY after the commencement of operations at the Sullivan concentrator, the use of a pilot table was instituted in order to present a visual control of various products by showing the amount of galena still present in the tailing from several stages of flotation. Among the products so treated, the final tailing was later included. It was sratifying to note that very little free galena was escaping, but a fine streak o a whitish mineral appeared at the concentrate zone. This mineral was identified as cassiterite. The amount was small and the newly recognized component in an already complex ore was considered primarily as of academic interest. However, the problem of recovering a usable metal was intriguing and, as opportunity presented itself in temporary lulls in research on Sullivan and other ores, the concentration of tin was a useful 'bit of knitting' to go on with. It was recognized from the start that the bulk of the mill tailing would have to be floated and the residue subjected to gravity treatment. Since one of the predominating features of Sullivan concentration operation has been the necessity of fine grinding, the problem of gravity concentration was thereby intensified. Several batch runs were made, and sufficient pulp was treated to produce about one ton of final tin concentrate assaying 67 percent tin. The overall recovery was under 30 percent and the estimated profit at full tonnage was only marginal. Testing was resumed several years later, when the price of tin again appeared attractive, in an attempt to develop a more compact plant with better recovery of tin. The weakness of the original plan of concentration was the large number of tables required to treat a feed so low in tin.

Jan 1, 1941

By J. H. Brown

"THE need for continuing education has been recognized only in fairly recent years as a major concern of the engineering profession. Formerly, it was acknowledged that engineers were required, at least informally, to follow the professional literature and to give some attention to new technical and technological developments. However, those relaxed days, when progress could be followed in a casual or incidental evening of reading, have disappeared in these days of mushrooming information. The engineer is now in the position of the man trying to control the flow from a fire hydrant with a child's pail. Our problem is that of developing an effective flow system -be it trough, hose, pipe or a bigger pail.The first step in achieving an effective means for continuing the education process is to realize that the need for the system is really an outgrowth of an increasingly sophisticated society. It is merely one more symptom of that society; others would• include the facts that new engineering graduates are more highly trained than those of several years ago, that graduate schools are now the norm and that even some fairly recent technologies are becoming outdated. There-fore, let us examine the education-al systems from which the bulk of the increasing sophistication has grown."

Jan 1, 1966

By Ronald G. Hamm

"With the advent in Canada of large open-pit equipment, the associated wire rope required must keep pace, especially in design and construction, along with the field that leads to increased rope life.This paper will first describe the various types of shovels and draglines in use today and also the unique characteristics of the wire rope required to efficiently service this equipment.Emphasis will be placed on the special equipment and techniques required in the wire rope manufacturing, along with the maintenance procedures required for a profitable operation.IntroductionOpen-pit and strip mining is increasingly playing an important role in the Canadian mining industry.An integral part of the surface mining industry is the excavation equipment used both to strip the overburden and remove the actual orebody. Two of the more prominent pieces of equipment are the electric power shovel and dragline. These two types of equipment have increased significantly both In size and number over the last decade.Wire rope plays a significant part in the operation of these machine s. Proper selection of the correct wire rope as well as proper maintenance procedures, can result in a major saving of a mine's wire rope consumption.The most prominent ropes for shovels are the hoist ropes. Some shovels also employ crowd and retract ropes. Boom pennants are manufactured from both wire rope or galvanized bridge strand.The most prominent ropes for dragline excavators are hoist, drag, and dump ropes. Some dragline excavators have boom hoist ropes, and most large dragline excavators have a boom suspension system using galvanized bridge strand."

Jan 1, 1983

By P. O. Parfitt

At the McIntyre mine, there are two distinct operations: a gold mine with narrow veins, mined by cut-and-fill methods, and a copper mine with large, open, long-hole stopes. The application of the Critical Path Method to scheduling work in the copper mine, where it has been used successfully for several years, is de-scribed briefly. This application is relatively simple. Use of C.P.M. has now been extended to the gold mine. To replace the former method of scheduling from bar-charts, a procedure was developed for scheduling automatically. To handle an operation of this size and complexity, a computer was essential. Improved schedules are now being produced, with a saving in time.

Jan 1, 1967

By A. McMullen

"IntroductionTHE LOW-VOLATILE bituminous coals of the Brazeau field, Nordegg, Alberta, are soft and weak in structure. The seams contain .bands of inferior material, locally designated 'black jack', and thin bands of friable carbonaceous shale having no definite horizon but usually 'floating' in the seam. Because of the weakness• of the coal and the friable nature of the shale bands, run-of-mine coal usually contains a very high percentage of fines, as •Shown in the following table:SIZE WEIGHT. %Plus 1/2 in 25.61/2 – 1/4 in 13.31/4 - 1/8 in 14.6Minus 1/8 in 46.5The most convenient way of cleaning the fine coal would be by treating it in association with the coarse coal, so that no additional plant would be necessary. To a limited extent this is possible in certain types of equipment, notably the jig. A system of washing without pre-sizing is not •attractive, however, when dealing with the friable coal under consideration, which contains •a preponderant proportion of fines. At the new Brazeau washery, separation is made at 3/8-inch on •a Robins 'Vibrex' •screen, the coarse sizes being cleaned in •a standard pulsator-type jig. A feldspar jig is used to clean the minus 3/8-inch fraction."

Jan 1, 1954

By Horace Freeman

The sulphur consumed in Canadian pulp mills and acid plants is worth approximately three million dollars annually and amounts to one hundred and fifty thousand long tons, all of which is imported from the United States. Concurrently with a decline in the value of newsprint there has been a gradual increase in the price of this raw material. Most pulp mills in Canada are situated within reasonable distance of domestic pyrite deposits; nevertheless it has not yet been found possible to mine these deposits and utilize the contained sulphur in competition with the imported material. It is the purpose of this paper to elucidate the reasons therefor, and to describe? a commercial-scale experiment undertaken with the object of introducing a native raw material into the Canadian pulp industry on the purely economic basis. Reasons for the Preferred use of Sulphur The known sulphur deposits in the United States are very large, so that at least a twenty-year supply of this material is assured. It is recovered cheaply and in pure condition. Although large deposits of pyrite are known in Canada, nothing has yet been developed to compare in size, cost of mining, or purity with the United States material. It has been necessary to handle and transport more than two tons of pyrite to equal a ton of sulphur.

Jan 1, 1930

By D. Groenveld, M. Rozou

"Recent trends move towards automation, smart sensors, internet of things, powerful DCS, and more data. Are those trends already utilized in a real time production environment? Today operators still have to monitor several complex processes at the same time and predict their behavior based on an overwhelming amount of data available.The fact of the operator being overloaded and humans being unable to process multivariable problems shows the need of a tool merging essential data and providing consistent, sound decisions for long-term profitability.This paper shows a successful execution of ABB’s process improvement services in Aitik (Boliden SA), a copper mine located in Sweden. Soft sensors, fuzzy rule blocks and model predictive control were seamlessly integrated in the control system of the grinding area, resulting in proper control of mill loads and particle size without violation of any constraints.INTRODUCTIONDepending on the ore characteristics and the targeted plant capacity, the design of the grinding circuit may vary significantly. Typically, the circuit consists of several mills (rod, ball, SAG, AG) in series and/or parallel with a number of classifiers and sumps at appropriate locations. The goal of the grinding section is to reduce the ore particle size to a level that enables efficient separation between gangue and precious metals in the subsiding processing step. The trade-off between quality and quantity has to be made. It is also crucial to execute this process step at the lowest possible energy and grinding media consumption.An optimal grinding process controller must manage to maintain a given fresh feed level while keeping the product size within a given range without violating any constraints such as power, torque or load limits. To accomplish the aforementioned, it is necessary to manipulate the ore feed rate, water feed rate and the mill speed. The most significant disturbances adding another degree of complexity to this control problem are ore hardness and the amount of circulating load."

Jan 1, 2016

By Leon J. Perrier

The paper describes the equipment in use, haulage grades, road conditions, tire sizes, tire performance and related problems. Various types of failures and causes, corrective action taken, tire records and reporting for control are also discussed.

Jan 1, 1977

By M. Sukhram, S. A. Argyropoulos

"In the aluminum and steel processing industries there is a need for velocity sensors to measure the flow characteristics of liquid metal. This paper will present a sensor and an inverse heat transfer technique to determine the direction of velocity in flowing liquid aluminum. Experimental research work with the sensor involving liquid aluminum was conducted, using the Revolving Liquid Metal Tank at the University of Toronto, which rotates 50 kg of liquid aluminum with velocities up to 0.35 m/s. Experimental data for various magnitude of velocity demonstrate that the sensor records different thermal profiles under different fluid flow conditions. Using the transient temperature information and the inverse technique, the direction of velocity of the molten aluminum flow field can be inferred. INTRODUCTIONOur research at the University of Toronto has focused on developing invasive sensors to determine the velocity of high temperature liquid metals. High temperature in this setting is defined at VALUES (in excess of 660 °C. The discussion which will persist in this manuscript involves detecting the direction of flow in liquid aluminum using an inverse heat transfer technique. We first reported on the sensor which is used in this article in the following two publications (Sukhram and Argyropoulos, 2011a; Sukhram and Argyropoulos, 2011b). The motivation to perform this research is due to the lack of sensors available to characterize the conditions within a high temperature liquid metal reactor/vessel. A report conducted by The Minerals Metals and Materials Society (TMS Energy 2011) has suggested that the introduction of sensors into molten metal processing environments has the potential to increase process efficiency up to 15%. Such sensors will aid in the understanding of high temperature liquid metal processing operations with the goal to implement more efficient process design and practice."

Jan 1, 2012

By J. Lipp

The lion share of lithium produced globally originates from South American salars. The standard operation for lithium production utilizes an array of evaporation ponds. This process consume vast areas and is either very slow when relying on solar evaporation - roughly 18 months of residence time; or with very high energy consumption since over 90% of initial water volume needs to be evaporated. A new technology, based on solvent extraction was developed. Results indicate a distribution coefficient up to 30, and selectivity greater than 1,000 towards Na extraction. The loaded solvent is stripped using a strong mineral acid, and the product solution is the lithium derivative of that stripping acid. Utilization of this new LiSXTM technology results in reducing the area needed for a commercial plant as well as reduces the residence time. In addition applying different stripping acids can diversify the product line of such facility.

Jan 1, 2014

By Shin-Kun Ryi

The world nowadays faces many challenges associated with excessive utilization of fossil, fuels, such as poor air quality and greenhouse gas emissions. Hydrogen appears to be an attractive alternative to the conventional, fossil, fuels with better energy efficiency and less environmental, impact. Pd and Pd-based alloy are the most often used membranes for hydrogen separation due to their superiority over other membranes. However, the stability of the commonly-used thin Pd-based composite membranes at high temperatures still, remains a big challenge. In this presentation, we will, report our progress on thin Pd-Ru alloy composite membrane by electroless plating high temperature applications.

Jan 1, 2010

By G. M. Humphrey

It is a great honour and privilege to be here in this distinguished company of the outstanding men in the mining industry and the political life of Canada. I fully recognize that I am so honoured as a symbol of the combination of American and Canadian leaders in industry who are partners in the sponsor-ship of the Quebec-Labrador iron-ore mining development which we are undertaking, and as such I want to express our great appreciation of the co-operation and assistance we have met on every hand in Canada, and the genuine friendliness and never-failing courtesy which we are always accorded. We are quite aware that it springs primarily from the very high regard in which our partner and sponsor, Jules Timmins, and our other Canadian associates are held. Their high standing among you is well known and we quite naturally fall heir to the benefits of the great esteem in which you hold them. Jules Timmins and his long-time associate, John Knox, were the original inspiration for our participation in this venture. It was their enthusiasm and vision which caught our interest and led to our joining with them in the years of exploration and search which have brought us to the threshold of this great development where we stand today. So much has been written of the details of our exploration and plans for future development that it would bore you for me to review them further here, but there is a phase of this development, and an extremely important phase of it, which I think has passed almost unnoticed and which it may be well worth while for me to bring to your attention this evening.

Jan 1, 1951

By H. A. Steane

THIS PAPER describes the re-grind section in the 2,000-ton per day, lead-zinc flotation mill of Canadian Exploration Limited, near Salmo, B.C. There are two re-grind units in operation, one in the lead circuit, and one in the zinc circuit. In each unit, the rougher concentrate is re-ground ahead of the cleaning circuit. These re-grind units have made valuable improvements in the concentrate grade, and with no loss in recovery by over-grinding galena or sphalerite. Since the initial installation of this re-grind section, the plant throughput has been increased gradually from 1,600 tons to 2,000 tons per twenty-four hours, and, as shown by the screen analysis of mill tailing, a coarser overall grind has been accepted, from 55 per cent to 45 per ?cent minus 200 mesh. There has been no increase in grinding capacity, but two mills have been taken from the main grinding circuit and used for the re-grind circuit.

Jan 1, 1958

By A. H. Lang

THE recent production of important quantities of high-grade muscovite at the Purdy mine, near Eau Claire, Ontario, bas brought that district into prominence and bas added another strategic mineral to the list of Canadian products. The discoveries are thirteen miles west of Mattawa and about two miles north of the Trans-Canada highway and the Canadian Pacific railway. HISTORY Clear mica of low power factor is in considerable demand in Canada and in the United States for war purposes such as radio and telephone condensers, aircraft spark-plugs, radio tubes, and transformers. Some muscovite (white mica) bas been produced in North Carolina and New Hampshire, but the United States trade bas depended largely on importations of muscovite from India and of phlogopite (amber mica) from Madagascar. For many years Canada bas been a substantial producer of phlogopite, but was unable to compete extensively in the United States with importations from abroad. Canadian production of muscovite bas been negligible as no important deposits were known. Ever since the construction of the Canadian Pacific railway, attempts have been made from time to time to mine the pegmatite dykes in and near the Eau Claire area, but, although some feldspar has been mined, no appreciable muscovite was produced. Lace in 1941, J. Purdy and H. MacDonald discovered a dyke containing large crystals of high-grade muscovite from which they are reported to have sold $700 worth of mica. They recorded claims 35974 and 35975 in December, 1941, and claim 36095 in May, 1942.

Jan 1, 1943

By Ralph L. Rutherford

Geologists or mining engineers familiar with geology are frequently requested by mine operators to give correlation in-formation regarding some mining property with respect to an adjacent area on one at some greater distance. It is the object of this article to mention a few of the difficulties involved in securing this information and to point out some of the salient factors upon which correlation is dependent. In view of the nature of the following discussion, a brief statement of the general character of coal formations .. seems appropriate. Coal formations, by reason of their environment of deposition which is in fresh or brackish water, exhibit the features common to continental deposits, in contrast to those of marine deposits. Such deposits are characterized by rapid variation in thickness and in lithological character both later-ally and vertically. (Plate 1 A). They consist essentially of sandstones and clay shales with all gradations between them, and also a few beds of coal and frequently some conglomerates.

Jan 1, 1924

By J. Contreras

In the period 2003-2004, the situation of the copper concentrate market was unfavourable for smelters and refineries, with low TC/RC values and euro-dollar parity affecting European companies negatively. Within this scenario, Atlantic Copper decided to develop a plan to increase its competitiveness and to improve its results in these market circumstances. The plan affected all departments in the Company and was based mainly on cost reduction in energy and manpower. A general analysis of the Complex's overall efficiency was carried out and, based on this analysis, two major Projects emerged, "Primavera" and "KF". Each Project consisted of smaller sub-projects which aimed at improving the areas which could perform better according to our general analysis. The paper describes how this entire project developed and the final results obtained by the Company.

Jan 1, 2007

By Joseph F. Daniels

In recent considerations of the utilization and beneficiation of coal, the chemise and the chemical engineer have been occupying the centre of the stage with their presentation of the picture of new fuel forms. The stage hands and supernumeraries of the cast, the miners and the consumers who carry the brunt of the present-day burdens, are apt to be forgotten in the glorious settings and the climaxes. With no thought of disparaging or of minimizing the efforts of our fellow scientists, let us remember that economic considerations as well as technical difficulties will limit these chemical applications, which must develop and move slowly before reaching the stage of industrial application at some later day. In the meantime, the coal-mining industry must live on hard faces rather than rosy dreams. In these brief notes it is my purpose to call attention to some of the physical advances in the utilization and beneficiation of coal which have been of interest to the industry in the State of Washington.

Jan 1, 1928

By E. Godfrey

The average man one meets on the street thinks of an explosive as a medium of death and destruction, something unstable which should be given a wide berth, because he knows little or nothing about its use or its stability. Briefly, explosives are compounds that develop very large quantities of heat and gas in an extremely short time and in a small space, thereby exerting enormous pressure upon surrounding bodies, and by the rapid expansion of this highly heated gas are able to perform a considerable amount of useful work. The amount of heat generated and the volume of gas produced by the decomposition of an explosive determines the amount of mechanical work it can do, and the time occupied by its change from solid or liquid condition to gaseous condition determines its shattering effect. Explosives manufactured by reputable people are not extremely dangerous, on the other hand they are quite safe if handled in a proper manner. Furthermore, before an explosive can be placed on the Canadian market a sample must be submitted to the Explosives Division of the Mines Department, who may condemn or permit its manufacture, according to their findings regarding its safety in handling and its stability during storage.

Jan 1, 1926

By S. Parkash, A. J. Szladow

Vigorous agitation of suspensions of coking coals in water (or light mineral oils) will often result in catast rophic loss of caking properties. It is shown that this deterioration is not a consequence of oxidation of the coals (by dissolved oxygen), but that it can be qualitatively connected with internal "solid-state" reactions which appear to derive their activation energies from cavitation of the liquid.

Jan 1, 1971