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As land resources decrease, commodity prices increase, and technology evolves, deep sea mining is becoming a viable alternative to meet the increasing demand for minerals. Successful deep sea mining operations are built on sound identification of the resource, proper selection of equipment, a thoughtful production plan, and good project management. These four key activities can be further optimized by analyzing how the spatial variability and uncertainty of the ore body properties impact the final mining operation. To address this problem, IHC Merwede is in the process of developing a risk quantification framework in the context of deep sea mining, which makes use of state of the art geostatistical simulation methods and transfer functions to quantify geological uncertainty and translate it into decision or project risk. The paper introduces the Local Average Subdivision method (LAS) for generating simulated models of the deposit and presents a new extension to incorporate point measurements of geotechnical or ore grade properties. Due to its computational efficiency, the presented method is suitable for simulating largely extended sea floor deposits. The second part of the paper illustrates, through example case studies, the significant benefits of a risk based approach which translates geological uncertainty into financial or operational performance indicators. In particular, the focus is on assessing financial project risk and on the design optimization of the deep sea excavation equipment by analyzing cutting forces, specific energies, and power requirements.

Aug 1, 2013

By T. W. Wlodek

"AbstractSatisfactory mine drilling operations depend on the good performance of the drilling machine, and of what may be called the drill set, i.e., the following four elements: bit, attachment, drill rod, and shank end. The field performances of these four elements in the drill set are analysed and their service lives are compared. The most .common causes of service failure are reviewed and possibilities of increasing service life are discussed.The laboratory methods now employed for the simulated service testing of tungsten carbide bits, conical push-on and threaded .types of attachments, drill rods, and shank ends are described, and some results are discussed. The objectives of the research programme now being carried out •on the above mentioned elements are outlined.A number of mines in British Columbia, northern Ontario, and northern Quebec have been visited, and, with the co-operation of the C.I.M. Branches in these areas, meetings with representatives of the mining and steel industries concerned have been held. In this paper, the mechanical-metallurgical problems most frequently encountered and discussed during these visits and meetings are described and .analysed.IntroductionSUCCESSFUL mine drill operations depend to a great extent on• the satisfactory field performance of the four elements which form the mining drill set, shown diagrammatically in Figure 1.These important elements are:1. -The bit, which may be one of the following types:(a) Detachable tungsten carbide bit( b) Inserted rod bit, so called chisel bit( c) Detachable steel bit( d) Solid rod bit"

Jan 1, 1952

By Côme Carbonneau

The ten -year case history of La Société Québécoise d'Exploration Minière (SOQUEM) is reviewed under the headings of the company's raison d'être, objectives, policies, structure and final goal. A brief analysis of its past operations is presented: aborted efforts, findings and developments. A projection is made of the future earnings, in terms of estimated present value, of its three main discoveries - Louvem , Niobec and Selim.

Jan 1, 1978

By D J. McDougall

Due to changes in the solid-state conditions of minerals in the rocks surrounding hydrothermal, contact meta-somatic or metamorphosed ore deposits, positive or negative thermoluminescent anomalies may be found in their vicinity. Several types of equipment which can be used for both quantitative and semi-quantitative measurements of the emission are discussed and compared. Methods of selecting, preparing and testing samples to ensure reproducible results are outlined, along with the kind of data which can be obtained from different types of equipment. The normal thermoluminescence of rock-forming min~ erals in the common rock types is noted, and variations in the solid-state conditions in the wall rocks which will cause marked increases or decreases of true thermoluminescence are outlined, as well as the thermolum-nescence-like emissions which are present in the vicinity of ore deposits. Introduction T HERMOLUMINESCENCE occurs when certain crystalline materials are heated to temperatures ranging between 180' and 400°C. The light emission can be ascribed to the release of electrons metastably trapped within the crystal lattice, with peak emissions taking place at temperatures which are more or less specific for a particular set of traps; the area under

Jan 1, 1965

By T. L. McCall

CHANGES in mining practices have evolved so quietly and unobtrusively that perhaps we scarcely appreciate how truly startling these changes are unless we cast our minds back so as to compare the past with the present. Such retrospection is, indeed, necessary when attempting to forecast the future, for it is only by carefully reviewing the past that we can hope to obtain an indication of what the future may hold in store. In this instance, it is not necessary to delve into the very early history of . coal mining, as our purpose will be served if the last three or four decades are reviewed, a period that is still fresh within the memory of many of us. These earlier days might be termed the selective period of mining, for at that time the coal resources of the world had not been tapped to anything like the extent they are at present and this condition enabled the owners and operators to exercise selective powers and only mine such seams of coal as could be most easily reached an worked at the lowest possible cost and which, at the same time, would suit the requirements of the market. Carrying this thought of selective mining still further, the miner, who was then an artisan skilled in all the branches of his calling, was able to select or discard such parts of the seam he was working that the co al sent out of the mine was acceptable to the consumer with just the barest minimum of preparation. Compare these conditions with the? conditions prevailing today, when coal seams of medium height, good quality, and readily accessible have been largely depleted and the operator has been compelled either to carry on his operations under much greater depths of cover where the coal is more costly to win, or else to work seams of lesser height or of poorer quality.

Jan 1, 1938

As a bubble travels through the pulp region of a flotation cell, it will collect the most hydrophobic particles of an intermediate particle size range, this being the primary source of true flotation selectivity. Despite its role on bubble-particle attachment, however, particle hydrophobicity is still missing a mathematical definition that can be used for plant simulation. In this paper, particle hydrophobicity is defined in terms of the induction time necessary for attachment and then linked to the mass of collector adsorbed per particle. This allows particle hydrophobicity to be written as a function of density of collector adsorption as well as particle size and mineralogy. The model is calibrated from the experimental measurement of the flotation rate constant. Liberation data from an industrial flotation rougher is used for model validation. It is demonstrated that the model can describe a broad experimental dataset by means of a minimal number of parameters. Main industrial application is in simulating the effect of the chemical environment upon plant metallurgical performance.

Jan 1, 2006

By V. N. Mackiw, H. Veltman

"A process is described which permits the separate recovery of lead and zinc from complex low-grade sulphide concentrates such as are produced from the New Brunswick type of disseminated pyrite ores. This process calls for the preparation of a lead-zinc bulk concentrate from the original ore by flotation. The bulk concentrate is then oxidized under pressure in autoclaves in aqueous sulphuric acid solution, such as return electrolyte from zinc electrolysis. This yields a zinc sulphate solution and a residue containing lead sulphate, unaltered pyrite and elemental sulphur generated during the oxidation. After the oxidation, the leach slurry is briefly heated to above the melting point of elemental sulphur and then cooled. Thus, pellets containing pyrite and elemental sulphur are formed, and they are separated from the lead sulphate by screening and/or flotation. Laboratory tests have shown that about 95 per cent of the zinc and lead can be separately recovered from complex bulk concentrates. Process possibilities are discussed."

Jan 1, 1967

By J. W. Spyker, D. H. Filson, W. H. W. Husband

"Large deposits of sodium sulphate exist in southern Saskatchewan in the brines or muddy crystal beds of alkali Jakes. Currently, more than 300,000 tons per year of sodium sulphate are produced from these lakes and sold as salt cake to the paper industry. Most of the production is obtained from the brines of a limited number of Jakes.The Saskatchewan Research Council was requested to develop a process for recovering sodium sulphate from the muddy crystal beds so that this type of deposit could be exploited in the future. A flowsheet was developed with the aid of phase diagram data and the process was studied on a pilot-plant scale using raw material from three different lakes. Satisfactory yields and product purities were obtained in all cases, and an economic analysis indicated that a 100,000-ton-per-year sodium sulphate plant could produce salt cake at a cost of $12.26 per ton for a rate of return upon investment of 16 per cent at current market prices."

Jan 1, 1966

By P. H. Agson Gani, T. Sitorus, N. P. Widodo

"PT ANTAM UBPE Pongkor underground mine use blasting to develop its tunnels which will cause poisonous and dangerous gases trapped inside mine. To analyze this case, a study of mine ventilation, the dispersion of carbon monoxide (CO) gas concentration and diffusion coefficient is commenced. At the end, the re-entry time formula will be determined. Results indicate that this study is site specific and could only be applied in the place this study executed. The aim of this study is to be further developed by applying Principal Component Analysis (PCA) to find a universal re-entry formula. KEYWORDS Mine Ventilation, Re-Entry, Smoke Clearing, Diffusion Coefficient, Carbon Monoxide Gas, Gas Dispersion INTRODUCTION Pongkor underground mine is using cut and fill as its mining method. Thus, its development and production processes require blasting to develop its tunnel. This process caused poisonous and dangerous gases spread and trapped inside the mine, one of them is carbon monoxide (CO) gas. CO is formed in an unbalanced reaction of explosives detonation and could be the cause of headache, blackout and death to people who inhale CO at certain concentration (McPherson, 2011; Hartman, Mutmansky, Ramani, & Wang, 2012). Mine ventilation system is installed in the mine to resolve this problem. Mine ventilation play an important role to disperse CO gas by absorb the poisonous/dangerous gases and deliver clean air into mine. The important parameter is diffusion coefficient, because diffusion is affecting particulates or gasses spreading from its sources throughout the mine. Diffusion coefficient is the total diffusion in axial direction of turbulent flow mainly by convection of bulk motion, advection and eddy diffusion, while the effect of molecular diffusion is appreciably negligible (Widiatmojo et al, 2015). Taylor (1953, 1954) develops a theory about the dispersion by inducing a slow stream of solvent into a capillary tube. Taylor used Reynolds assumption of radial diffusivity to be analogous with the transfer of the matter in turbulent flow as well as the transfer of momentum and heat. Then, Taylor proposed the formula of diffusion coefficient, D (m2/s), against pipe diameter and turbulent shear velocity are as follow:"

Jan 1, 2019

By George P. Demopoulos

For more than 20 years the author had the privilege of working closely on a number of R&D projects with Lucy Rosato and her team at CEZinc. Several of these projects were driven from the sustainability agenda that Lucy Rosato championed as an innovation leader that supported research collaborations. Highlights from this highly rewarding collaboration are to be presented in this paper. In particular we will deal with the following works-topics: (a) iron control via solvent extraction as alternative to jarosite precipitation; (b) production of high-density gypsum by controlled neutralization of simulated zinc plant process/waste waters; (c) selenium removal from weak acid solutions; (d) electrolyte purification by cementation; and (e) manganese control by oxidative precipitation with SO2/O2.

Jan 1, 2015

By Laura Steeves, Inoka Eranda Perera, Jhon Silva, Arend Spaeth

"This paper reviews the main concepts ruling the design, implementation and performance of active explosion barrier systems for underground coal mines in the USA. The document examines the parameters needed for the design of this type of system, such as overpressure and flame speed, suppressant deployment speed and duration time of the active barrier. The document also discusses the available solutions for gassy mines and the concepts behind the selection of machined mounted and roadway active explosion barrier systems. The paper includes a review of active explosion barrier systems developed in the USA and South Africa. The paper provides an overview of the current status of this technology in the underground coal mining industry in the USA, and the possible implementation of such systems. The paper concludes with the identification of the future work needed for the successful implementation of the systems in several conditions to enhance the safety of underground coal mine operations and to provide more tools to the miners for their safety.INTRODUCTIONUnderground coal mine explosions can be addressed in two ways, through prevention or mitigation. The United States mining industry practices have emphasized the prevention of explosions in underground coal mines, with little being done to mitigate the explosion once it occurs. Despite successful practices for the prevention of underground coal mine explosions in the US, the threat of an explosion does still exist. Other mining countries around the world have developed and implemented mitigation systems such as active explosion barriers in their underground mines. In the 1970s, the United States Bureau of Mines (USBM) carried out extensive research on the use of active or triggered explosion barrier systems in the US; however, they are not currently used.Explosion barrier systems do not prevent explosions but mitigate the propagation of the shockwave and flame to other areas of the mine. The use of active explosion barrier systems enhance the safety of underground coal mines. Active or triggered explosion barriers will detect the arrival of the shockwave or flame front of the explosion and release inert material to suppress or extinguish the flame. The technology required for active barrier systems is readily available based on their presence in other mining countries and must be adapted for their use in US coal mines. The adaption must consider the coal dust and methane concentrations in US coal mines, the mine geometry, and the mining equipment used."

Jan 1, 2019

By Charles Camsell

At the Annual General Meeting of the Institute in 1924. I endeavoured to present the position held by the mineral industries in the commercial life of this country. The facts and figures were presented at that time in a detached way. Since then, however, I have made some attempt to analyze them in order to determine the causes for that position and to draw some conclusions as to the future of the mining industry. As everyone knows, our trade figures are very often used in political discussion, especially in discussion of tariff policy. It would be entirely out of order for me to say anything touching the tariff issue and I want to have it clearly understood that, in my opinion, the material I am about to present contains not a single statement or conclusion which anyone would be warranted in using as an argument for either a lower or a higher tariff or for tariff changes of any kind. As a starting point, let me re-state, very sketchily, Canada's general situation in external trade. In the last calendar year, 1924, we sold Canadian merchandise of all kinds to other countries to the value of $1,045,000,000 in round figures. Our purchases abroad reached about $893,000,000. Thus our sales exceeded our purchases by roughly $152,000,000. In other words, we had what is known as a 'favourable balance of trade' - one of the biggest favourable balances we have ever had in our history. The proceeds of our sales of Canadian products enabled us to meet the bills for all our purchases of foreign commodities and, in addition, placed a large surplus to our credit with which to offset our interest charges and other obligations abroad.

Jan 1, 1925

By A. R. Pasieka, J. C. Wilson

"Compressed air still remains an essential source of power in underground hardrock mining. As a power medium it has a high convenience factor, although, in many cases, it is expensive to generate and maintain. Until new methods of breaking rock and/ or satisfactory alternatives to air-driven rock drills are developed, compressed air is indispensable. It is essential to utilize this source of power to a maximum by keeping all pneumatic tools supplied with air in adequate quantity and at optimum pressure.In search of the optimum operating air pressure, con-trolled drilling tests were undertaken at dynamic pressures ranging from 90 to 140 psi.Test results show the effect of increasing air pressure on: the performance of various jackleg drills at varying pressures, the life cost of drill steels and TC bits, and drilling efficiency at varying pressures. From the fore-going, a criterion is proposed for selecting efficient rock drills, and, also, optimum air pressure at each mine can be determined for its particular conditions."

Jan 1, 1966

By L. C. Stevens

The particular purpose of this paper is to direct attention to the development of underground conveying as applied to methods of working coal in the mines of Alberta. Historical A retrospective view of coal mining discloses a continuous effort, on the part of those interested, to substitute mechanical contrivances for hand labour. A patent for a coal-cutting machine was granted to Michael Menzies in 1761, at which time much of the transportation of coal underground was accomplished by means of sledges. Early forms of cutting machines attempted to duplicate the action of a miner's pick, and one hundred years lacer than Menzies? patent we still find this class of machine, driven by water power or compressed air, in use to a limited extent. A coal-cutter using the principle of a circular saw and worked by hand was exhibited in London in 1851, and from these crude beginnings the machines of today have been evolved. Transportation of coal underground has similarly been subject to considerable improvement. The above mentioned Michael Menzies took out a patent in 1750 covering the use of a self-acting incline plane, which is probably the earliest record of any system devised to lighten the load of the crammer or car-pusher of those days. In the year 1868 the Gillot & Copley machine was patented, this being a compressed-air-driven disc coal-cutter which proved highly successful. The chain cutters were a natural development from this type, and for a number of reasons they have been even more successful in the majority of cases.

Jan 1, 1930

By G. M. Swinkels

Sherritt Gordon and Cominco, with financial assistance from the Canadian Government through PAIT, have developed a hydrometallurgical process for refining copper from sulphide concentrates. The main objective of the project was to develop a process applicable to a wide range of concentrates with respect to copper content, other metals content and impurities, within the economic parameters set by present smelting and refining practice. Other important objectives were to recover sulphur in its elemental form and not as sulphur dioxide to assure improved hygienic conditions and a negligible impact on the environment. For the most abundant and relatively refractory chalcopyrite concentrates, the first step of the process is thermal activation with hydrogen to decompose chalcopyrite and pyrite, commonly associated with it, into more reactive sulphides more amenable to leaching. The iron is then selectively extracted by sulphuric acid leaching and subsequently rejected as jarosite. High-bornite concentrates do not require thermal activation and acid leaching; they are subjected to another hydrometallurgical iron removal step. The high-grade copper sulphide resulting from iron removal, and containing all of the initial precious metals, is then leached under oxygen pressure to produce elemental sulphur and copper sulphate solution . After suitable solution purification, the copper is recovered by high-current-density electrowinning as wire-grade product. Precious metals remain in the leach residue and are recovered after separation of the gangue materials and elemental sulphur. The laboratory and pre-piloting test work had indicated copper and precious metals recoveries comparable to those achieved in current practice. The process was shown to be suitable for handling relatively low-grade concentrates and, in addition, it was capable of high recoveries of associated zinc, molybdenum, nickel and cobalt in saleable form.

Jan 1, 1978

By T. W. Wlodek

"AbstractThe results of research into the fatigue properties of SAE 1080 carbon steel and nickel-chromium-molylbdenum steel for mining drill rods are analysed and described in detail.The effect of water corrosion on the fatigue strength of drill rods of these two steels in the as-rolled condition has ,been investigated and the beneficial influence of shot-peening on their dry and water-corrosion fatigue strengths determined by employing the method developed previously (1).Eight S-N curves for as-rolled and shot-peened mining drill rods under both dry and water corrosion conditions have been derived and their shape and relative position are discussed. The main features relating to field performance of the drill rods are analysed.Purpose of Research and Outline of ProgrammeDRILLING holes in rock and ore by means of drill rods attached to a pneumatic drill is a basic procedure required in mining operations. Detonation of explosives placed in these holes is at present the only practical method of breaking down the rock and ore.A drilling rod is supported by its bit end in the drilled rock. Its shank end, fixed in the drilling machine, transmits impact energy to the cutting edges of the bit. On the field performance of the drill rod depend a number of basic mining operations such as sinking, drifting, and stoping. The drill rod is there-fore regarded as one of the most important tools used in the mining industry."

Jan 1, 1952

By J. R. Andrews, R. P. Young, J. M. Reyes-Montes

"Microseismic monitoring provides insight into the location and extent of rock-mass fracturing induced by cave mining, enabling interpretation of the cave profile and validation of predictive numerical models. Source location uncertainties can lead to misinterpretation of the inferred characteristics of the fracture network. One principal source of uncertainty is the velocity model used to invert the location algorithm. Large-scale 3D numerical models of modulus changes across a caved mass can represent such complexities in the location algorithms, allowing more accurate interpretation of the microseismic activity. A Northparkes mine case study applies this advanced approach to microseismic data interpretation.RÉSUMÉ Le suivi microsismique fournit des renseignements sur la localisation et l’étendue des fractures de la masse rocheuse induites par l’exploitation par blocs foudroyés; cela permet d’interpréter le profil de la chambre foudroyée et de valider les modèles prédictifs numériques. Les incertitudes quant à la localisation de la source peuvent conduire à des mésinterprétations des caractéristiques inférés du réseau de fractures. Une des principales sources d’incertitudes est le modèle de vitesse utilisé pour inverser l’algorithme de localisation. Des modèles numériques tridimensionnels à grande échelle des changements du module d’élasticité à travers une masse foudroyée peuvent représenter de telles complexités dans les algorithmes de localisation, permettant ainsi une interprétation plus juste de l’activité microsismique. Une étude de cas à la mine Northparkes applique cette approche avancée à l’interprétation des données de microsismicité."

Jan 1, 2016

By A. Gronningsater

Introduction As is well known, the fight between the blast furnace and the reverberatory furnace in copper smelting during the second decade of the century ended with a victory for the latter, a result which must largely be attributed to the introduction of flotation methods. To my knowledge, no new blast furnace has been blown-in at any American copper smelter since the War. As the metallurgy of nickel, up to and including matte smelting, is generally considered a close parallel to that of copper, the introduction of reverberatory smelting in the big new smelter of the International Nickel Company at Copper Cliff, built in 1928-30, seemed a logical adherence to a well established trend. In view of these facts, considerable comment was made when Falconbridge Nickel Mines decided to retain the blast furnace in their smelter built about the same time, in 1929. A presentation of the reasons governing this choice should therefore be of interest. The basic principles underlying the Falconbridge practice, and the considerations guiding the successive steps in the operations, will be discussed in the following. To understand the problems involved, the character and mode of occurrence of Sudbury ore must be kept in mind. Large amounts of disseminated ore are generally present. Although the gangue usually runs only about 50 per cent Si02, the ore hoisted as a rule contains more silica than needed in the smelting operation; until recently this excess was removed entirely by hand picking (in later years supplemented by magnetic sorting methods), a difficult and not very satisfactory method, in which 'the border line between ore and waste is entirely arbitrary, and therefore too much depends on the judgment of the picker.

Jan 1, 1934

By Jean-Paul Drolet

"This paper charts, briefly, the :salient facts of international trade in minerals and their products and Canada's place in it. It also reviews inter-national agreements, economic groupings and national measures to channel and regulate production and trade in minerals. Canada's mineral industry now produces raw materials worth $3.7 billion per year, making this country a giant among mineral producers. Two-thirds of this production is exported, chiefly to the United States, accounting for about 30 per cent of Canada's merchandise exports and topping all other classes.However, several other nations are also pressing the development of their mineral resources and markets. The Soviet Bloc, China and principally Australia and Africa are becoming important suppliers of basic raw materials to some traditional markets of Canada in Europe and Japan.The outlook for Canadian mineral exports to the countries of the Common Market, Great Britain and Japan is good, although some tariff barriers remain troublesome.Concerning the United States, our most important market, Canada is seeking to have that country lift import quotas on lead and zinc, and re-cent statements by U.S. authorities give hope that this may be achieved soon. Moreover, Canada wishes to obtain easier access to the American market for several of its metals and minerals.Canada is now participating in the Kennedy Round of tariff talks under the auspices of the General Agreement on Tariffs and Trade (GATT), and is seeking to open wider doors for its exports of products.In summary, Canada has done reasonably well in some mineral commodities on world markets, but has lost ground in others. Any slackening of Canada's efforts in the development and marketing of mineral resources would soon lead to the decline of its role in the world miueral economy."

Jan 1, 1966

By Erwin L. Zodrow

THE AUTHORS welcome this timely opportunity to comment o n a paper by MacLean and Merner (" Room-and- Pillar Mining at the Prince Mine of the Cape Breton Development Corporation " , ClM Bulletin , June 1978, pp. 59-62) concerning the rock falls and their relation to "a change in the strata". First, however, it is proper to express our gratitude to the Cape Breton Development Corporation, and in particular to A. R. MacLean, for making it possible for us at the College of Cape Breton to start two new collections. The first of these is a fossil plant reference collection from the Sydney Coalfield, Cape Breton (Upper Carboniferous period) , and the second is a documentation of the role o f pyrite in the formation of hydrated sulphates (samples from No. 26 Colliery, 1-B Mine, and the Prince Mine at Point Aconi). Conditions of sedimentation in the deltaic-type basin of the Upper Carboniferous time in the Point Aconi area were such that on the (coal) swamp, now represented by the Stubbart (or Hub) seam , (a) clays of varying thickness and extent were deposited , (b) biogenetic sulphur was introduced and (c) flora were buried. These are essentially the culprit s that make rock falls possible and at the same time predictable over large areas (in the present mine). The clays lithified to become shale, and biogenetic sulphur combined with iron to become pyrite (marcasite?), which exists as nodules and in fine-grained layers.

Jan 1, 1978