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By N. Behnood, W. Pascheto

"Laboratory wear tests are important tools that can be used for the evaluation of materials for wear applications and mitigation of wear problems in the mining industry. However, laboratory test parameters must be fully characterized and test results must be carefully interpreted if a material selection is to be made. Failure to do so may lead to erroneous conclusions. Suitable lab-oratory tests are valid only if they reflect the field conditions to which materials are subjected. Therefore, it is important to know, in detail, the field conditions, as well as the wear test techniques being considered. It is important to recognize the limitations of the various wear tests and the wear test data published in the literature. This work will review present wear testing technology, including the various wear tests avail-able, wear test equipment and test limitations. Several wear test procedures will be related to common equipment used in the mining industry.IntroductionThis paper will concentrate on non-lubricated wear mechanisms, because they are the most costly to the mining industry. Very frequently we are faced with the task of selecting materials for wear applications or improving existing systems that are giving poor performance. There are plenty of examples in the literature of practical wear cases and ranking of materials for wear applications. It is also very common to find materials manufacturers’ data -sheets listing wear tests results by comparing their materials performances against those of competitors. Much of the published wear data lack the description of the type of wear test, test parameters and the type of wear mechanism to which the data should be applied (if any).Before considering wear test data for a specific problem one should ask which type of wear mechanism is involved? What type of test and what test parameters were used to produce the results? Even if the type of wear tests and parameters are known, how accurate and useful are the published wear data? How are the results related to a particular type of wear? It is important to point out that even the standardized wear tests, such as those in ASTM standards, have limitations. Such limitations are recognized and clearly spelled out in the standards themselves. Basically, wear tests may lead to erroneous results if the test is not able to repro-duce the same wear mechanisms encountered in the field. Therefore, the use of published results may be helpful, as a starting point, but may be of little value for a final material selection.This work will discuss the main types of non-lubricated wear mechanisms encountered in the mining industry. In addition, it will discuss the many wear tests available and their correlation with the various types of wear mechanisms. The limitations of several standardized wear tests and the limitation of using published wear data will also be discussed."

Jan 1, 1997

By Deni Côte, Marcel Vallée

"The Guide to the Evaluation of Gold Deposits reviews the successive evaluation steps in the domains of geology, engineering, and economics. The Guide analyzes, in a systemic perspective, the sequence of exploration, development, and evaluation work required to bring a mineral deposit to production. The aim is to identify the metal/mineralization losses and ore dilution that each work step contributes to the evaluation and mining process. The procedure allows one to maximize the income and profits of a mining operation, and to reduce the risks of financial losses tied to investment decisions in the mining sector. For greater efficiency, the criteria of reserve estimation and classification should be integrated with the evaluation steps and methods. At earlier stages of deposit development, when quantitative knowledge is available mainly on the geological axis, the term ""delimited mineral deposit"" should be used. The term ""reserve"" should be used only in an operating mine or in a mining project, when information in the geological, engineering, and economic domains is adequate to ensure technical and financial feasibility. ""Reserves"" are by definition ""mining reserves"". Each category of proven/probable reserves and measured/indicated deposits should be subdivided into two classes to express better the many steps of mineral valuation. The category of ""possible reserves"" shall be replaced by that of ""inferred mineralization"". This system, derived from the Australasian Code, can easily be integrated into current practices of the exploration and mining industry within a short timeframe. The proposal to develop the use of the margins of error of the estimates at a confidence level of90% should be viewed in a longer timeframe. Establishing the precision of the mineral inventories and distinguishing between categories and classes by means of the margin of error will require more work and a longer break-in period.SOMMAIRELe ""Guide d’évaluation des gisements d'or"" analyse, dans une approche systémique, les travaux d'évaluation et de mise en valeur des gisements minéraux dans l'axe de la géologie, dans l'axée l'ingénierie et dans I ‘axe de l'économique. L’objectif est d'identifier la contribution aux pertes de métal et à la dilution du minerai des diverses étapes de l'évaluation et de l'exploitation du gisement. Ceci aid erra à maximiser les revenus et les profits, et ainsi, à réduire les risques départe financière que comportent les décisions d'investissements dans le secteur minier. Pour atteindre ces objectifs, iI est essentiel de relier les critères d'inventorie et de classification des réserves aux méthodes d'évaluation des gisements. Aux stades antérieurs du développement minéral, lorsque les connaissances quantitatives ne s'étendent qu’à l'axe géologique, le terme ""gisement délimite"" sera utilisé. Le terme ""réserve"" ne sera utilisé que dans une mine en exploitation au dans un projet minier, lorsque l'information dans les axes de la géologie, de l'ingénierie et de l'économique sera appropriée pour en garantir la faisabilité technique et économique. Chaque catégories des réserves, prouvée et probable sera subdivisée en deux classes pour mieux qualifier les niveaux d'évaluation du projet. La catégorie actuelle des réserves possibles sera remplacée par celle des ""minéralisations inférées"". Plusieurs essais démontrent que le système propose, qui s'inspire du Code australasien, peut facilement et rapidement s'intégrer dans les pratiques de l'industrie. II pourrait également contribuer à une standardisation des méthodes et des nomenclatures à l'échelle internationale. La proposition d'utiliser les marges d'erreur des estimes au niveau de confiance de90%pour caractériser les estimations se situe dans une plus longue perspective. Cette application demandera des développement méthodologiques additionnels ainsi qu'une période de rodage."

Jan 1, 1992

By Bert S. Hall

"IntroductionThe purpose o f this paper is to review the evidence at hand concerning the earliest centuries of cast iron in Europe, from roughly 1400 A.D. until the second half of the sixteenth century. For the most part it is concerned with the relationship between two technologies which emerged first in China and then later appear in Western lands, gunpowder weapons and iron founding. We should not assume, as I hope to show later in this discussion, that weapons constituted the only product for which the iron founder had any market, but it is clearly true that attempts to produce weapons constituted the most severe technical challenge for the early founder. Firearms appear for the first time in Europe in the 1320s and develop into significant weapons on the field of battle by the end of the century. Theirs is a complex history, subject neither to easy summary treatment nor to simplified models of development. I hope to be able, through the analysis of the evidence concerning cast iron, to show that one important strand in the fabric of gunpowder's history concerns the materials from which cannon could be made. This question is subject to a number of shades of meaning, because ""cannon"" can be made for many purposes under a profusion of different names, and under sharply varying conditions of use. As a result, the question of materials is frequently really a question of competing materials, and involves a complex set of factors, of which production costs and the ultimate safety of the user seem the most important. Judged in this manner cast iron was an important but unsatisfactory metal for weapons purposes until 1543, at which time English founders learned to make iron muzzle-loading cannon which could rival bronze ordinance in most important performance criteria, but which cost much less to produce. With that event, the history of cast iron and the history of weapons entered into the close relationship that persisted until the advent of rifled artillery made of steel in the middle of the nineteenth century."

Jan 1, 1983

By D. S. Cronan, S. P. Varnavas

Abstract - Metalliferous precipitates from submarine hydrothermal discharges have been investigated at four inshore locations off Milos in the Hellenic Volcanic Arc. The fine fraction of the sediments shows considerable variability in the concentrations of elements frequently associated with hydrothermal activity. Manganese varies from 30 ppm to 2500 ppm, encompassing the entire range of values found off Santorini also in the Hellenic Arc. Iron occurs in lower concentrations than off Santorini and Yali, while other elements often associated with hydrothermal activity such as Pb, Zn, As, and Cu also show enrichments in sediments from the hydrothermal vent areas. Selective leaching studies have shown that most elements are variably distributed between the different phases of the sediments but with enriched Pb, Zn, and Mn mainly in easily soluble secondary phases. Hydrothermal inputs are strongest at Palaeochori Bay, less at Voudia Bay and lowest at the Airport Springs and Rivari. The weathering of sulfide and possibly other orebodies is also thought to contribute to some of the elements enriched, while background concentrations are largely supplied from detrital sources.

Jan 1, 1999

By MAX VOS

Lithium is the lightest and electrochemically most reactive of all metals. Renewed interest in lithium coincides with research in lithium batteries and power generation by atomic fusion. Ontario lithium resources are contained in spodumene pegmatites that can form where medium- to high-grade metamorphic volcanic-sedimentary formations are intruded by pegmatite and porphyritic granitic rocks. Spodumene pegmatites occur in at least twelve locales throughout northern Ontario, all of which are in the Superior Province of the Precambrian Shield. Tantalum, cesium, rubidium, beryllium, niobium and tin also were noted with lithium in spodumene pegmatites. Considerable potential remains for discovery of additional lithium and rare-element pegmatites in northern Ontario.

Jan 1, 1984

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 Erwin L. Zodrow

"This paper is based on a statistical analysis of the Smallwood iron ore mine (6). In this mine, the prediction of magnetite is especially difficult because of strong trends. Recognizing the statistical limitations of the sample data, the paper approaches the basic statistical analysis of the magnetite by endeavouring to obtain a first approximation of its sample density function. The knowledge of the distribution of a random variable is essential for several reasons, but particularly: (1) to obtain reliable estimators of the population parameters -for example, mean and variance; and (2) to use these estimators in hypothesis-testing concerning future experiments -sample points and sample intervals."

Jan 1, 1968

By M. L. Smith

"In the Phosporia formation of SE Idaho, ore quality varies by depth, seam and distance along strike; phosphorus recovery is sensitive to these variations. Plant ore feed can be blended over time to minimize this fluctuation by using a combination of mine production and inventory stockpile scheduling. Mixed-integer and goal programming has been used to optimize short-term mine production, but the seasonal nature of mine haulage requires the use of stockpiles both at the mill and the mine. The contents of the stockpiles can also be optimized as part of the production scheduling problem, but introducing inventory control introduces a nonlinear term into the formulation. A solution using a piecewise linear formulation is modelled and solved using AMPL/Cplex, and solution strategies are discussed for similar large-scale problems. IntroductionIdaho’s minable deposits of phosphate rock are found in the Meade Peak member of the Phosphoria Formation; two separate zones of this formation are mined with a combined thickness of 30 ft to 60 ft. A generalized stratigraphic section of the Phosphoria section is shown in Figure 1, illustrating the degree of complexity encountered when scheduling mine production. Alteration of the formation results in higher grade ore zones near the surface and variable in P2O5 levels between seams and along strike. This variability is seen as well in other quality characteristics critical to the production of acid and elemental phosphorus. Further, plant recovery and nodule quality are sensitive to variations in ore feed; variability in SiO2, carbonates, moisture, organics (carbon), P2O5 and other constituents of the ore can strongly affect plant recovery. Because ore quality characteristics can vary as a function of the alteration zone (or seam) being mined as well as the depth and distance along the strike of the formation, scheduling of mine production can have a highly significant effect on recovery in the plant. As illustrated in Figure 1, there are nine seams containing 20% to 35% P2O5. Phosphoric acid and elemental phosphorus production requires an ore content of 30% and 25% P2O5, respectively. Variability between numerous beds that are mined and quality variation within a seam due to alteration greatly complicates production scheduling with the result that erratic mill feed characteristics greatly decrease recovery."

Jan 1, 1999

By J. A. MacLellan

"CONSTRUCI'ION OF SHERRITT'S CONCENTRATORSSherritt Gordon is operating two mills north of the 56th parallel, and is presently engaged in building a third. The author was closely involved in the design and construction of all three of these concentrators.The Lynn mill is the oldest of these three concentrators-it is a 4,000 ton per day nickel-copper plant built in 1953. The Fox mill is a 3,000 ton per day copper-zinc concentrator built in 1970. The Ruttan mill will be a 10,000 ton per day copper-zinc plant scheduled to go on line in July 1973.LYNN MILL The Lynn mill including the crushing, concentrating, drying and load out plant is about 69,700 square feet or 17.4 square feet per ton per day. '!his plant was originally built in 1927 at Sherridon, 150 miles south of Lynn Lake, as a 2,000 ton per day copper-zinc plant. In 1952 the plant was moved by tractor train to Lynn Lake. The whole plant was re-oriented within the original perimeter walls as a 2,000 ton per day nickel-copper plant. This plant was expanded to 4,000 tons per day by the addition of t1-Jo rod mills and a 5-1/2 short head crusher in 1959.The Sherridon mill processed its last ore in Sherridon in September 1951 and the first load of nickel concentrate was loaded at Lynn Lake on November 9, 1953 when the railroad arrived at Lynn Lake.The site for the Lynn Lake mill was cleared of overburden in the summer of 1952 and foundations for structural steel and SO!l8 equipment foundations were poured the late summer and fall of 1952 • Steel was erected from January to June 1953. Most of the equipment came in from January to March of 1953 by tractor sleighs. Sane sleighs upset but no equipment was lest through the ice."

Jan 1, 1972

By T. Hartmann

The presence of crud represents a permanent challenge for solvent extraction in the hydro-metal industry. The crud is a stable emulsion which slowly spreads along the phase boundary between the aqueous and organic phase. The crud can significantly impair the efficiency of hydro-metal extraction because the phase boundary between the aqueous and organic phases assumes substantial proportions, and the settlers cannot react flexibly. In a chain reaction, all settlers connected in series become infected with crud. The transfer of organic phase to the electrowining (EW) cell can cause 'cathode burn'. Continuous treatment of the crud is extremely effective and reliable with a 3-phase separating solid bowl centrifuge. All three phases are separated distinctly from one another. All associated process steps exhibit a steady uniform efficiency. First and foremost, they ensure a reliable, continuous extraction process and, second, they recover valuable re-usable organics from the crud.

Jan 1, 2007

By Paul Guliov

Potash dominates the industrial mineral scene in Saskatchewan accounting for 44% of total provincial mineral production in 1981. More than 7 million tonnes of potash have been produced annualy in recent years; ten underground mines are presently (1983) active. Sodium sulphate and cement are also important mineral products. Construction aggregates, clay products, bentonite, salt, peat moss and sulphur complete the list of industrial mineral products.

Jan 1, 1984

By H. Utsunomiya, Mehdi Sanjari, Abu Kabir, Steve Yue, Jing Su, L. Kestens, In-ho Jung

The microstructure and texture evolution of low temperature rolled AZ31 magnesium alloy during annealing were investigated. The specimens were rolled at the temperature of 100? at a high rolling speed of 1000m/min with a reduction of 30% in one pass. Annealing was conducted at various temperatures ranging from 200? to 500? for different time. To study the effect of fast speed rolling, the same annealing procedures have been applied for the specimens rolled at a significantly lower speed of 15m/min. The microstructure was characterized by optical microscopy and scanning electron microscopy, while the texture was analyzed by X-ray diffraction analysis and electron backscattered diffraction analysis. Texture weakening occurred during annealing at both fast and slow rolling speeds. However, at the same annealing condition, fast rolled specimens always had weaker intensity of basal texture than slow rolled ones.

Jan 1, 2014

By D. Letzig

Wrought magnesium alloys are of special interest as lightweight structural components as a result of their more homogeneous microstructures and improved mechanical properties compared to cast components. Extrusion as a shaping technology offers the possibility to produce a wide variety of magnesium alloy profiles. In this contribution we describe the role of extrusion parameters such as extrusion speed, ratio and temperature as well as the type of extrusion process on the microstructural development of AZ-series magnesium alloys and the resulting mechanical properties. The effect of microstructure on the tensile/compression deformation behavior of the alloys has also been investigated. Aspects of process optimization designed to overcome technical and economic limitations and thus establish magnesium alloy profiles for industrial applications will also be discussed.

Jan 1, 2006

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 X. -G. Chen, E. M. Elgallad

Direct chill (DC) cast ingot plates of 2xxx alloys have been increasingly used for large mold applications in the plastics and automotive industries. A novel heat treatment practice for Al-3%Cu-1%Mg DC cast ingot plates has been developed, involving solution treatment, furnace cooling to the desired aging temperature and holding for appropriate time at the aging temperature. The mechanical properties of the plates were studied for different combinations of aging temperature and time, using hardness measurements and tensile testing. The evolution of the strengthening precipitates was investigated under different cooling rates corresponding to cold water quenching, still-air cooling and furnace cooling, using electrical conductivity measurements. The results showed that by applying the novel heat treatment, the cast ingot plates could provide a wide range of combinations of strength and ductility satisfying the design specifications of large molds. This, in turn, offers a practical solution for the fabrication of extremely large DC cast plates combining between good mechanical properties and low levels of residual stress using the shortest possible heat treating cycle.

Jan 1, 2015

By J. B. Edwards

"The case is presented for the use of simulators for the computer-based training (CBT) of mining plant operators and for introducing them to automatically controlled systems. As well as their use in the classroom, the role of simulators is examined for ""on-plant"" use in trouble-shooting, fault-finding and maintenance of automatic systems. Case studies are presented showing how specific simulators are becoming established or have potential in the areas of automated materials handling, machine testing, setup and guidance. The evolution of scientific simulations into simulators of widespread practical use is discussed and present-day limitations of computer speed and graphics are considered. Related areas of research for the Canadian Centre for Automation and Robotics in Mining (CCARM) are identified.IntroductionCCARM's Commitment to Simulator DevelopmentAs automation is progressively developed and exploited in mining operations, there arises an urgent need to educate and train staff responsible for its introduction and operation in our mines and for its maintenance. For this purpose , an essential ingredient of an automation program is the development of appropriate mining system simulators for use by a wide variety of personnel. The author has been fortunate to have been closely involved with the development of automatic control systems for a variety of mining machines and mining systems in the United Kingdom. A key ingredient of the research phase in each case has been the use of simulation techniques. As projects have moved toward their commissioning and exploitation phase, the simulations have evolved into simulators tailored for use by machine operators and maintenance personnel. Illustrative case studies are presented later. The researach of the newly constituted Canadian Centre for Automation and Robotics in Mining (CCARM) will likewise involve extensive simulation, and the development of simulators (from the scientific programs) for use at the mine by operators and technicians will be given high priority in the Centre's over-all work program."

Jan 1, 1990

By C. C. Walden, D. W. Duncan, P. C. Trussell

Thiobacillus ferrooxidans released copper from -400-mesh chalcopyrite at a rate of 54 mg/I/hr. Any flotation chemicals remaining on the concentrate did not inhibit the leach rate. Zinc rougher tailings were also leachable. With bacteria, 75 per cent of the zinc and 68 per cent of the copper came into solution. In the sterile controls, only 16 per cent of the zinc and 10 per cent of the copper were released; 100 per cent of the copper and 36 per cent of the zinc were leached from pyrite cinders through the action of bacteria, and 17 per cent of the copper and 10 per cent of the zinc were solubilized in the sterile controls. Less than 0.027 per cent of ~he iron came into solution. The majority of the copper in a converter slag was acid-soluble, but a reverberatory slag responded to microbiological leaching. About 62 per cent of the copper came into solution, compared to 12 per cent in the sterile control. The various factors influencing the rate and extent of microbiological leaching are discussed.

Jan 1, 1966

By Noel Brien, O&apos

General: National Asbestos Mines Limited has operated an asbestos mine and mill near Thetford Mines, Quebec, since 1958. As a result of additional exploration of the orebody in 1962-63, it became apparent that long-range mining plans would have to be revised to allow for a large increase in both ore and waste tonnages. It was decided that the task of checking out possible mine designs could best be analyzed by a computer to obtain data from which an optimum open-pit configuration could be plotted. Object: It was desired to arrive at an optimum open-pit configuration with an over-all pit slope of 45 degrees and a minimum operational width of 200 ft. at the bottom. Calculations were based on assay values from diamond drill holes in cross sections of the mine. The computer's assignment was to select and describe, by coordinates, the optimum cross section for the mine. Mine engineers then assembled the various optimum sections to produce the pit outline. As this would not necessarily result in a practical mining arrangement, the computer also provided alternate solutions,

Jan 1, 1965

By P. M. Huck, R. John

"The National Uranium Tailings Program was established in 1982 to develop, in part, a mathematical predictive model which would allow the assessment of the impact of uranium mill tailings on the environment and particularly on humans. . To achieve this , various studies were undertaken to establish the role played by key constituents of the tailings. This paper summarizes the findings of a study carried out under that program, to examine the leachability of barium-radium sulphate sludges produced in the treatment of uranium mill tailings decants. The investigators performed detailed chemical an alysis of the sludge, applied geochemical computer models to investigate sludge leaching behaviour, and conducted experiments to assess the impact of bacteria on leaching. The modelling showed that the redox state o f the sludge-leachant system was the most important factor. Substantial bacterially-mediated dissolutio n of the sludge and release of radium was demonstrated experimentally under suitable reducing conditions . INTRODUCTIONIn September 1981, Phillip A. Lapp presented the final report of the National Technical Planning Group on uranium tailings research to the federal government (Lapp, 1981). Lapp' s group had performed an in-depth survey of the status of uranium tailings research in Canada and, as a result, recommended that a national program be funded in the amount of $18 .6 million. Half of this fund ing was to come from the federal government, with the two producing provinces , Ontario and Saskatchewan, providing the balance. However , the provinces declined to support the program and the federal government decided to inaugurate a reduced program with $8.5 million o f funds .In late 1982, the formation of the National Uranium Tailings Program (NUTP) was announced by the minister of state for mines. A primary objective of this program was to develop a mathematical predictive model that would permit the assessment of the impact of uranium mill tailings on the environment, a nd particularly on humans. The program was to use existing information to the greatest possible extent, and then fund research to fill in gaps or substantiate data where necessary .The NUTP was established to administer this program of contract research over a five-year sunset life. By the end of the 1986-87 fiscal year the NUTP had completed about 100 contracts. One of those projects was to study the effect of placing barium-radium sludge ba ck within the tailings matrix. Th is paper gives the results of that study."

Jan 1, 1989

By J. P. Norrie

The presence of copper-bearing rocks in the Coppermine River area of Arctic Canada has long been known. Word of this was probably circulated along the Arctic and Hudson Bay coasts by the Eskimo, who no doubt traded articles made from native copper among themselves. It is not known whether any of these ever reached the southern shores of Hudson bay. The Indians, also, knew of the occurrence of copper here, as they served as guides to Hearne when he made a successful trip over land from Hudson bay to the Coppermine river. The possible commercial importance of these copper deposits was early appreciated by the Hudson's Bay Company, who on December 7th, 1770, despatched Samuel Hearne from Fort Prince of Wales, now Fort Churchill, to investigate them. He reached the then unnamed river at a point forty miles from its mouth on July 14th, 1771, and after surveying the river to its mouth and naming it the Coppermine, he retraced his steps to Fort Churchill by an overland route. Hearne's expedition was probably the most remarkable and arduous ever attempted in Arctic exploration, but the actual value derived from the trip was entirely out of proportion with the hardships he must have suffered. He verified the occurrence of native copper, but his astronomical and other observations were of little value. Until 1912 no concerted effort was made to obtain any definite information as to the geology and economic value of the Copper-mine deposits.

Jan 1, 1931