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By P. van Dorssen

In South African metalliferous mines, stoping operations are largely confined to narrow, tabular orebodies making mechanization extremely difficult. Limited flexibility in terms of stope width has necessitated drilling by means of handheld, pneumatic rock drills at most of our operations. As the largest producer of platinum in the world, we drill in excess of forty million stope blast holes per annum. Cleaning of the broken ore is also done by conventional means?utilizing scrapers and scraper winches. Conventional methods such as these carry high costs in terms of risk exposure as well as labour intensity. The purpose of this paper is to describe the development of a long hole stoping system suitable for the narrow platinum reefs. The new system had to be substantially safer and more cost effective than conventional mining. We selected a site that was conducive to mechanized mining and set out the parameters that we considered would meet our requirements. We then conducted a feasibility study to evaluate the conceptualized long hole stoping system in terms of specific goals. An analysis of the proposed system identified the Key Performance Indicators (KPIs). One of the most critical goals was to be able to create a man-free stope. This would mitigate the safety risk associated with normal stoping operations, as well as the inefficiency cost previously referred to.

Jan 1, 2002

By W. G. Matteson

The origin of the salt domes of the Gulf coastal plain has been investigated by many of the most able geologists, but the problem cannot be said to have been satisfactorily solved. Since 1860, numerous theories have been presented, only to be discarded, at least in part, as more complete infomation revealed their fundamental weakness. Real progress toward solution dates from 1902, when Hill1 advanced the theory of secondary deposition of the domal materials from saturated solutions of hot saline waters ascending from great depths under hydrostatic head along structural lines of weakness. Shortly thereafter, Harris,² using Hill's hypothesis as a basis, explained the doming and pronounced uplift associated with these salt cores as the result of forces exerted by growing salt crystals. This was a marked advance over the ideas of Coste3 and Hager,4 since no evidence of igneous intrusives, as they assumed to explain the uplifts, had been found associated with the domes. Harris5 developed his theory until it offered such apparently plausible explanations of so many details of dome phenomena that his hypothesis and conclusions received widespread acceptance, despite some serious objections, and today his theory, somewhat modified, is considered by many able investigators to be the best explanation of the origin of these domes. The immense production of oil per acre, the recognition of the high lubricating quality of the oil, the development and recognition of the efficiency and advantages of oil-burning vessels, with the subsequent exceptional demand for fuel oil, and the resultant advance in the price of coastal crude, have been responsible for a prospecting and develop- 1 Robert T. Hill: Beaumont Oil Field with Notes on Other Oil Fields of the Texas Region. Jnl. Franklin Inst. (1902) 164, 143. 2Gilbert D. Harris: Rock Salt in Louisiana. Louisiana Geol. Survey Bull. 7 (1907) 76. ³E. Coste: Volcanic Origin of Natural Gas and Petroleum. Jnl. Canadian Min. Inst. (1903) 6, 73. 4Lee Hager: Mounds of the Southern Oil Fields. Eng. & Min. Jnl. (July 28, 1904) 78,137, 180. 6Gilbert D. Harris: Geologicel Occurrence of Rock Salt in Louisiana and East Texas. Econ. Geol. (1909) 4, 12.

Jan 1, 1921

By D. J. Kennedy, A. W. Stokes, W. G. Klinowski

Sulphur hexafluoride (SF6) has become an accepted standard in the field of mine ventilation tracer gas studies. It has a wide variety of uses for defining mine ventilation flows that cannot be adequately described using conventional instruments such as anemometers and smoke tubes. The Cape Breton Coal Research Laboratory (CBCRL), Energy, Mines and Resources Canada, has been using SF for the past 4 years and has developed numerous release and sampling systems to increase its versatility. The CBCRL has also completed a successful field trial of an automated rapid sequential SF6 analyzer (which gives a pseudo real-time readout) that can be used underground. In doing this work, the authors recognised the potential of being able to use more than one tracer gas simultaneously in an underground study. Two alternative tracer gases (Freon-13B1 and Freon-12) have already been used by CBCRL in some of their underground work. These gases can be measured by gas chromatography utilising an electron capture detector in a similar manner to SF6. A description of these gases, the methods for 6' their handling, release and sampling are given in this paper together with a brief outline of the analytical system used to measure them. Their suitability to mining applications is compared with SF6. A study in which these three gases were used together is discussed and the results and conclusions given. Some of the additional uses for multiple tracer gases to assist the mine ventilation engineer in resolving problems and improving his day-to-day monitoring are discussed. Finally, a brief analysis of developments which can be expected in the near future is outlined.

Jan 1, 1987

By Thomas J. Menner

Jan 1, 1983

By M. E. Wadsworth, R. L. Pearson

THE dissolution of UO, in carbonate solutions can occur only il the tetravalent uranium is oxidized to the hexavalent state. The carbonate system is of particular interest because it provides a means whereby the oxidized uranium may be dissolved by forming the complex ion UO,(CO3)3-1. In the presence of oxygen the over-all reaction may be written UO+1/2O,4CO3T+2HCO2UO,(CO4)11+H2O [1] UO, was used in this study because it could be obtained in high purity and also because it is representative of the most refractory of the primary uranium minerals. The mineral ulrichite is the natural counterpart of the synthetic UO, used. The kinetics of the leaching of UO, should be similar for any of the uraninite type minerals. A pressurized system was used not with the hope it could be extended to commercial systems as a primary purpose but simply to provide the means whereby important temperature and pressure parameters could be varied for the evaluation of the kinetic processes. The importance of such pres-

Jan 1, 1959

By Robert E. Hoffman, John B. Hudson

The self-diffusion coefficient of pure lead has been measured at five pressures between atmospheric and 40 kb. over a temperature range of about 150°C near the melting point at each pressure. Measurements were made using a radiotracer technique, samples being sectioned electrochemically after the diffusion anneal to determine the diffusion penetration curve. Pressure was applied in a "belt" type pressure device similar to that used by Hall et al., in the diamond synthesis. The self-diffusion coefficient, D, can be represented by an equation of the form at constant pressure, and an equation of the format constant temperature. An apparent correlation between the effects of pressure on self-diffusion and on the melting point of the material observed by Nachtrieb et al., at pressures below 10 kb. was found to be only approximate as measurements are carried to higher pressures. OVER the course of the past 30 years a large number of studies1-' of the rate of atom movements in solid metals have been carried out. These studies have in general been aimed at increasing the understanding of the detailed atomic process by which atom movements in metals can take place. The largest portion of these studies consisted of measurements of the self-diffusion coefficient, D, as a function of temperature. From such studies con- siderable information regarding the energetics of the motive process has been deduced. Recently such measurements have been extended to the pressure dimension. However, the existing work in this area is scanty and has in the past been limited to the pressures attainable in oil or gas bombs—i.e., up to about 10 kilobars (kb). In the present work, the self-diffusion behavior of pure lead has been investigated using the "belt" type high-pressure apparatus designed by Hall7 over a pressure range from atmospheric to 40 kb at temperatures extending over about a 150°C range close to the melting point at each pressure.

Jan 1, 1962

By Mark C. Malamphy

MAJOR JUAREZ TAVORA, who recently accepted the post of Minister of Agriculture in Brazil, has reorganized his department. Not least among those sub: divisions of the "Ministerio" which underwent radical changes in the general reform was the Serviqo Geologico e Mineralogico do Brasil. This well- known organization was declared extinct, and in its place was created a new cleparttnent ' termed "Departamento Nacional cle Producqao Mineral," which immediately took over all the work of the olcl Servico Geologico ill addition to certain new duties. Dr. .. Domingos Fleury- da Rocha, former head of the School of Mines of Ouro Preto, was called to Xio to assume the newly created post of Director General of the department of Mineral Production. His department will have live divisions :

Jan 1, 1934

By S. H. Jason Choi

The Systems Conveyance and Operations Program (SCOP) is being implemented to convey tertiary-treated effluent to Lake Mead near Las Vegas, Nevada. The Reach 3 Tunnel Project is part of SCOP. The tunnel?s planned location along and across the Las Vegas Wash creates challenging tunneling conditions. A number of feasible excavation and initial support methods are being considered during the final design stage. This paper describes how the tunnel construction options were refined based on anticipated tunneling conditions and compatibility between tunnel excavation and initial support methods. A brief description of the most significant characteristics of the anticipated ground conditions is included for the purpose of discussion.

By G J. Butler

Since 2005 BHP Billiton Iron Ore has been working with the consulting company Runge to implement the software XPAC Advanced Destination Scheduler (ADS) in life-of-mine studies. The Mt Whaleback mine, being the single biggest open cut iron ore mine in the world, presents some special challenges in scheduling. The biggest challenge has been the slow run time and difficulty in targeting all ore and waste requirements. The high waste to ore strip ratio means that much of the cost of mining is tied up in waste dumping. It is therefore very important to schedule waste efficiently. At Mt Whaleback there is an additional challenge of managing two types of waste: inert and environmentally sensitive pyritic material. This paper shows how the XPAC destination scheduler is configured to achieve efficient and repeatable waste scheduling results at the Mt Whaleback mine. It also discusses proposed improvements to the process. The overall ore and waste schedule is configured to target mining parameters, crusher feed and grades. The schedule is run in two stages. The first stage is ore mining. The waste that needs to be mined is locked in a sequence. The second stage is the waste scheduling. The waste destination scheduler uses three inputs: source waste parcels locked in a sequence, a haul road and a waste dump block model. The process involves setting some rules for dump progression and haul path selection. These can be validated. The schedule is then run to target the shortest travel time. The results of scheduling are graphical and numeric and can be transferred into many different formats for reporting. The graphical result shows face positions in time that can be used for detailed dump design. The numeric results are used to estimate truck fleet size, fuel consumption, labour and equipment financials. The process has been successful in reducing the project time line, increasing the ability to do more scenarios and increasing schedule accuracy, transferability and repeatability.

Jan 1, 2007

By A. N. Lazaridi, S. I. Afanasenko, S. A. Safonov

"This scientific work presents the results of comparative tests of centrifugal concentrators with a vertical and horizontal axis of rotor spinning. The article also describes a qualitative analysis of the behavior of mineral particles in a centrifugal field with fluidization for concentrators with a horizontal axis. The analysis was aimed at studying the effect of the quantity of fluidization holes in the basket on the degree of magnetite recovery and the effect of the basket rotation speed. The experiment demonstrated that concentrators with a horizontal axis are not inferior in terms of the qualitative recovery indicators to concentrators with a vertical axis. The researches also provided facts about the wide practical application of concentrators with a horizontal rotor arrangement. INTRODUCTION Methods of gravity concentration, attractive for their ecological purity, see their revival. First of all, this is due to the invention of centrifugal concentrators with the fluidization of the layer of mineral particles. The creation of a new generation of gravitational centrifugal concentrators made it possible to achieve a tangible breakthrough toward the direction of reducing the grain size of mineral particles effectively divided by density, up to 10 µm at a high production capacity of the vessels reaching 500-600 tons per hour. Such separators enable dressing a crushed ore of flotation grade and in some cases replace the flotation process, especially in primary operations, in joint cycles. In the long term, this method of concentration should significantly expand the scope of application, replace partial flotation processing, ensure the introduction of environmentally friendly energy-saving technologies at ore-processing plants. Summarizing the international experience for the last 30 years, it can be confidently asserted that centrifugal methods of concentration have become widely used in processing schemes for the separation of finely dispersed products in the mining industry. An interest in the creation of installations using centrifugal acceleration for the separation of mineral particles by density has particularly grown. Dozens of centrifugal concentrator designs have been created and continue to be improved. Centrifugal concentrators have a number of obvious advantages, which are especially relevant today. Losses of fine gold during the process of mining are well known. Gold washers screw, spiral separators, jigging machines and sluices traditionally used in the production processes do not solve the problem of fine gold recovery. Table 1 shows the results of comparative tests of a centrifugal concentrator (ITOMAK) and other concentration equipment. According to the research conducted by the company GMRS, Krugersdorp, South Africa (2000), the initial material was gold ore crushed to 150 micrometers (90%)."

Jan 1, 2018

By Alberto Benavides

El presente texto señala la evolución del sistema de energía eléctrica en diversos sectores entre el período de 1968-1977 y así evaluar su demanda en el futuro a través de fuentes hidráulicas. Actualmente, el potencial hidroeléctrico ha sido establecido en 29.257 MW en la cuenca del Pacífico y de 176,287 en la del Atlántico. Del potencial total se considera como factible de desarrollar técnica y económicamente 58,000 MW, lo cual es amplio para los requerimientos de la minería, ya que la actual potencia generada es sólo de 3% del potencial total.

Nov 1, 1980

By Mauricio Pero Diez de Medina

El presente texto describe los principales yacimientos de azufre contenidos en el departamento de Potosí, Bolivia. Las zonas auríferas se caracterizan por una serie de volcanes extinguidos que sobresalen del altiplano, donde existen lagunas y fuentes de aguas termales. A nivel regional se distinguen tres zonas: lava superior, zona piroclástica y lava inferior. Asimismo, la explotación, refinación y comercialización del azufre está a cargo de la Corporación del Seguro Social Militar (COSSMIL), del Grupo Barrero, del Grupo Clavija y en menor escala de las Cooperativas Mineras.

Mar 1, 1984

By Eddison Apaza

Durante las últimas dos décadas la minería en el Perú ha pasado por una serie de cambios en los diferentes tipos de métodos de minado subterráneo; por ejemplo, el muy conocido cut and fill que fue reemplazado por el bench and fill, lo que permitió diluir los costos operativos y a la vez incrementar la productividad. Tomando en cuenta que el método bench and fill tiene variables las cuales determinan su éxito, siendo la altura de banco la más preponderante ya que ésta determina los inputs como: el metraje de preparación, diseño de cable bolting y sostenimiento, LMA, tiempo de auto - soporte, etc; de la misma manera los outputs como la sobre - dilución, la estabilidad para la extracción, la fragmentación del mineral, entre otros.

Sep 29, 2023

These proceedings consist of an introduction and four descriptive papers. The first paper is an update on fire protection for large haulage vehicles, the second paper is concerned with improved visibility systems for large haul- age vehicles, the third paper is on improved ladders for large haulage vehicles, and the fourth paper is concerned with large haul-age vehicle operator training systems.

Jan 1, 1980

By John T. Atkins

Utah International's Shirley Basin Mine is located in the Southeastern High Plains of Wyoming at an elevation of about 7,100 feet. The Shirley Basin area is a gently rolling semi-arid land. The uranium ore zone occurs at depths ranging from 270 to 350 feet below the surface. Overburden consists of poorly consolidated sandstones, siltstones, and clays. Underground mining was begun in 1960. Conditions were made difficult by high rates of water inflow and ground support problems. The development of a solution mining I or in-situ leaching technique allowed underground operation to be abandoned in 1964. Solution mining provided limited production from 1963 to July 1970. In January, 1969, large scale development of open-pit mining was begun. A 1,200 ton per day mill went "on stream" in March, 1971.

Jan 1, 1973

For many years it has been known that large bodies of iron ore existed in Iron and Washington counties in Utah. The ore is chiefly hematite-both hard and soft-though some magnetite is found. No definite and complete estimate of the iron ore reserves of the state have been made. The U. S. Geological Survey estimated that 40,000,000 tons of ore were disclosed by development work averaging only 35 feet below the surface of the ore. The ore is found along an area about one and a half miles wide by twenty miles long, and for the most part on the eastern and southern slopes or foothills of Three Peaks. Granite Mountain and Iron Mountain. Later estimates by others have gone as high as ore in sight 164,000,000 tons, probable ore 300,000,000 tons and possible ore 1,000,000,000 tons. Whether this last estimate is too great or not there is sufficient iron ore in Utah to justify the starting of an iron industry. Two companies are now mining iron ore in Utah, the Columbia Steel Corporation and the Utah Iron Corporation. The mine of the Columbia Steel Corporation is at Iron Springs a few miles west of Cedar City. About 650 tons, of ore a day is being shipped to the blast furnace at Ironton. The ore is mined by the glory hole method. After being drilled it is blasted to the bottom of the several glory holes and is dropped through chutes into cars on the ore haulage level below. It is then hauled by electric locomotives to the crushing plant, where it is crushed to blast furnace size before going to storage bins. Some of the softer ore is brought to the chutes by Fresno scrapers.

Jan 1, 1925

By M. C. Messner, L. P. Davidson

The Giesche Spas Akcyjna, in Polish Upper Silesia, produces zinc, lead and coal, together with many byproducts emanating from the zinc-lead ores. The development of the concern in the 230 years of its existence has been influenced not only by metallurgical improvements but also to an unusual extent by political and economic factors. The company was founded by George Giesche, who was born in 1653 and died in 1716, and who in 1704 received from Emperor Leopold I the exclusive privilege of mining and selling galmei1 in Silesia. His children, who retained the business, gave the name to the firm—George von Giesches Erben. After 1802 modifications in the Prussian mining and corporation laws limited the rights formerly enjoyed. The family concern became a corporation and expanded its activities, building smelters and opening new mines. The establishment of the present eastern boundary of Germany resulted in the transfer of nationality of a large part of the mines and surface plants to Poland, which, in turn, necessitated the formation of a Polish company, the Giesche Spólka Akcyjna. The first concentrators at the Bleischarley mine were built between 1854 and 1860 and owing to dual ownership were two in number. They were used only for the treatment of galena. In 1873 a concentrator was built for the treatment of sulfide ore preparatory to treatment in the Recke roasting plant, which was the first to have an acid plant for recovery of the sulfur gas. This concentrator was replaccd by a larger one in 1888, when the present orebody was opened up. At the same time, a mill was built for the treatment of the galmei. The concentration of the sulfide ore resulted in a much higher grade of feed for the zinc plants after the first troublesome steps of the roasting process had been worked out. Consequently, the oxide ore in its primitively concentrated state was no longer highly valued as a retort charge. and steps had to be taken to increase its zinc content.

Jan 1, 1935

By C J. Adams, H J. Campbell, A J. Tulloch, I J. Graham

New Zealand can be regarded as a rifted part of mineral-prospective eastern Australia. Geologically credible comparisons between selected trans-Tasman and SW Pacific geological provinces and units, especially those that contain significant mineralisation in Australia, can help provide a useful exploration framework for New Zealand. As part of a six-year Mineral Wealth of NZ and its EEZ (MWE) research programme, we have targeted selected geological units in eastern Australia for comparison and contrast with their potential New Zealand counterparts. In future years, the programme will focus on geological units in New Caledonia.

Jan 1, 2005

By Philippe Poirier

Les parcs à résidus miniers représentent un risque environnemental qui nécessite une gestion adéquate. Suite à la publication du « Guide sur la gestion des parcs à résidus miniers » en septembre 1998, les membres de l?industrie minière ont appliqué les éléments de gestion du Guide, permettant ainsi une amélioration continue des opérations. En février 2000, l?industrie minière a indiqué le besoin d?établir des lignes directives plus spécifiques pour l?opération sécuritaire des parcs à résidus. Dans cette optique, l?Association Minière Canadienne a publié, en septembre 2002, un Guide pour l?exploitation, l?entretien et la surveillance (EES) des parcs à résidus miniers. Suite au développement du Guide et à son application sur plusieurs sites miniers, il apparaît que la mise en oeuvre d?un Manuel ESS des parcs à résidus miniers permet : ? d?établir les responsabilités des intervenants; ? de s?assurer que les critères d?opération sont appliqués; ? de mettre en oeuvre le plan de déposition des résidus et de gestion de l?eau; ? de rencontrer les normes et exigences environnementales; ? de définir un programme d?entretien et de surveillance des ouvrages; ? d?identifier les risques et de mettre en oeuvre un plan d?intervention d?urgence; de démontrer une opération diligente.

Nov 1, 2002

By Bertrand Wolfman, William E. Stanley

"This paper reviews the traditional mine accounting systems, including ""custodial accounting"" and unit costing, and then suggests that the use of flexible budgets represents a more suitable method of reporting costs in order to assist the mine manager in improving productivity. Examples of various applications are given to show that the result is a clear reporting structure.Custodial Accounting is Emphasized in Traditional SystemsTraditional mine accounting has been mainly concerned with the accuracy of financial reporting to ""head office"" for the use of the directors and the company's bankers and shareholders. This is often called custodial accounting and it represented the main purpose of accounting when first developed in Europe hundreds of years ago. This important development permitted the establishment of enterprises which were separated from their owners because they could rely on accurate financial reports of management's stewardship.As custodial accounting is fairly broad and historical in nature, it is often not very useful to the mine manager for ongoing monitoring of performance of mining, milling, maintenance, and other support and staff groups. In spite of the considerable investment in accounting staff and computer support, many accounting systems have not been upgraded so that they accurately reflect workplace performance on a weekly or monthly basis.Budgets are Often FixedMany mines today also still emphasize fixed budgets. Thus, the mine plan which is set in the fall of one year is converted to a monthly tonnage and detailed dollar budget for periods of up to sixteen months in the future. The only certainty in this plan is that actual events will differ; timing, mix of mining methods and production volumes will differ on a monthly basis.Unfortunately, the fixed budget has no capability to reflect these operational changes. It is frozen for the full year. The result is that actual results will inevitably be compared to an outdated target."

Jan 1, 1982