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Operations of the new copper smelter at Mount Isa commenced on the 6th February, 1953. Prior to this date a paper by R. V. Anderson (1953) outlined the smelter layout, proposed operation and expected performance.Nominally a 50-ton per day plant, output is currently at the rate of 85 long tons per day. In the first 3t years, of operation to 30th June, 1956, '71,339 tons of blister copper were produced. Operation has been stabilized' and a number of modifications to plant and operation have been made. This paper reviews the progress made to date.GENERAL LAYOUT AND EQUIPMENTThe general layout and equipment follows well-established practice as study of Figs. 1 to 4, and Appendix II will show. This diagrammatic representation of layout (Fig. 1) and flow sheet (Fig. 2) is intended for the purpose of brevity to take the place of a detailed plant description.Choice of site for the smelter was limited by the necessity for close proximity of the waste heat boilers to the powerhouse.Much excavation was necessary before foundation work commenced, but the plant is compact and further expansion is possible.CHARGE MAKE-UPRoaster charge initially comprised concentrates, purchased ores, revert materials, mine sulphide ore and barren sand. As purchased ore receipts increased and as domestic black rock oxidized ore became available, the latter two fluxes were eliminated from the charge. Fluxes at minus i-in. sizing are trucked from crushing plant or stockpile by motor lorries. Filtered mill concentrates are dropped from an overhead conveyor on to the storage patio floor adj acent to the two concentrate bins.

Jan 1, 1957

By Steve Kral

The domestic mining industry may be in the doldrums but there appears to be hope, at least from a regulatory standpoint. At least one US senator believes that the events of Sept. 11, 2001 made many citizens see the need for the country to become more self-reliant on its growing energy needs. Even before that tragic day, however, the Bush administration was making a strong push to open up more public land for energy and natural resource development.

Jan 1, 2002

By W L. Jennings

This paper summarises work undertaken to date as part of an investigation into the mineral resources of the proposedNorth West South Island National Park. The area covered by the proposed national park is underlain by many rock types that have undergone a long and complex history of evolution which has endowed it with some of the best potential for a wide range of different minerals in New Zealand. Many of these minerals occur only in this area or in Fiordland National Park.   The first gold-rush in the area occurred in 1856 and followed the discovery of payable gold at Lightbands Gully, south of Collingwood. The miners first focused on the alluvial deposits but soon shifted attention to lode potential. The total historical gold production for the area may be over 400 000 oz (NZ$250 - NZ$295.6 M at 1993 prices).   In addition to gold, a wide range of other minerals have been reported from the area including molybdenum, copper, nickel, zinc, silver, bismuth, stibnite, lead and antimony. The Onekaka iron-ore deposits have produced small tonnages of ochre and iron-ore at various times. Tungsten, platinoids and other metals have been. given only minor attention. The diverse geology of the Northwest Nelson has resulted in the occurrence of many industrial minerals which have been exploited in generally small-scale operations. Aggregate, chrysotile asbestos, clay, dolomite, marble, limestone, dimension stone, rip-rap, talc-magnesite and wollastonite have all been produced.

Jan 1, 1993

By M. Tanaji

Over the last many decades, a significant amount of research has gone into the domain of slurry transport. However, design engineers still face many challenges with respect to prediction of pressure drop, critical velocity and other design parameters as a function of Solids % and Particle Size Distribution (PSD). The industry requirement is to transfer the slurry at the maximum concentration as possible (above 30% (volume %)) to make slurry transport more economically viable and to reduce water consumption. To facilitate the design and scale-up of slurry transport in pipelines and in process plants, there is a need for a correlation that can predict slurry pressure drops over a wide range of operating conditions and physical properties of different slurries. The objective of this study is to overcome the limited range of applicability and validity of existing correlations and to develop a generalized but more rigorous correlation applicable to a wider range of slurry sys-tems. The existing Wasp et al. (1977) method is based on multi-phase flow modeling approach. This study attempts to modify this approach by considering material-specific values of Durand?s equation co-efficient and by defining flow regimes based on particle Reynolds number. When compared with experimental data, the modified Wasp method proposed in this study predicts the pressure drop for slurry flows more accurately than other available correlations. Also, the pro-posed method requires minimal test/experimental data for a particular slurry system and can be extended over different input conditions. An iterative computer algorithm is developed to calculate the criti-cal settling velocity and pressure drop in a pipe as a function of Solids % and PSD. The solution method can easily be implemented in de-signing slurry pipes, design validation, and studying the different slurry transport scenarios. The modified method can also be extended to accurately predict pressure drops in dynamic pressure flow networks used in commercial process simulators.

Feb 23, 2014

By D. Komljenovic, J. Paraszczak

"This paper presents the use of queuing theory in truck fleet sizing in open pit mining operations. In the first part, a methodology is developed by which an optimal ratio between the size of shovels and trucks may be determined. The second part gives the fundamentals of the queuing theory and its application in analyzing shovel and trucks. The stochastic character of involved times (loading, truck cycle, etc.) is taken into consideration. Using the above theory, the optimal truck fleet size in actual conditions may be estimated. Minimal operating cost of the working system (shovelstrucks) represents the basic requirement of the analyzed process. The methodology was validated on Caterpillar front-shovel – truck combinations. IntroductionLes camions représentent probablement les équipements les plus utilisés pour le transport dans les mines. Le coût de transport peut parfois atteindre 50 % du coût d’exploitation et 25 % du coût total (Collins, 1996; Kennedy, 1990). Il est critique pour une opération minière de le minimiser. C’est un sujet qui a été traité relativement souvent dans la littérature spécialisée. Les premières applications informatiques dans l’industrie minière ont été développées pour la détermination du temps de cycle des camions.Au fil des ans, la capacité des camions a augmenté et, aujourd’hui, les plus gros manufacturiers de camions (Caterpillar, Orenstein & Koppel, Euclid, Terex, Unit Rig, Komatsu, Liebherr, Belaz) fabriquent des camions ayant une capacité de 200 t et plus dont quelques-uns d’une capacité supérieure à 320 t. Pour les plus gros camions, le coût d’opération peut même dépasser 240 $US/heure dans des conditions modérées (Caterpillar, 1999). Les mines modernes de grande taille peuvent posséder plusieurs dizaines de camions dans leur flotte."

Jan 1, 2004

By Jorj O. Osterberg

Until ten years ago, the largest load tests on drilled shafts (bored piles) were about 3,000 tons (27MN). These tests were made with kentledge (large weights, usually concrete blocks) stacked up as a reaction to the applied downward load of a hydraulic jack. In some cases, the jack load is resisted by a load frame held down by piles or anchors connected to the frame. When the test loads exceed 3,000 tons (27MN), these methods become cumbersome expensive and time consuming. The Osterberg (O-cell) test method does not require any reaction load. It has become the only cost effective method for static load testing of high capacity shafts. Over 650 load tests have been performed with this method, 86 of which were over 3,000 tons (27 MN) and 40 over 5,000 tons (44 MN), and the largest test load was 17,000 tons (150 MN). Tests have been made on sands below the water table, shafts ending in rock sockets, and cemented sands and gravels. Test results and details for selected load tests are discussed.

Jan 1, 2002

By Martti Hagfors

The Finnish Defence Forces Technical Research Centre (PVTT) studied the effect of shape of boost-er to its ability to ignite insensitive (IM) plastic bonded explosive (PBX). Therefore an explosive fac-tory produced 20 insensitive (IM) plastic bonded explosive (PBX) charges for the tests. The mass of each of the charges was exactly 9.2 kg (20.3 lb). The charges were equipped by two different type of boosters; RDX and PETN. Both the explosives contained some parts of plasticizers. The weight of all the boosters was exactly 300 g (0.66lb). On the bases of their shape, the boosters were also divid-ed into two different groups, cylindrical and “pancake”. In the middle of the “pancakes” there was also shaped a small cone in such away that the detonation could accelerate to its full speed after the charge was ignited. The following shots were exploded;

Jan 1, 2013

By T Sasaoka, H Shimada

Mined-out limestone/aggregate quarries in Japan contain many high and enormous pit walls. Many precious resources are abandoned in these final pit walls. In addition, there are many mines which are located in or near populated areas in Japan. Utilisationof the potentially useful under- ground space at mined-out sites is a topic relevant to the practice of surface mining. This paper describes and discusses the concept of underground space utilisation and tunnelling systems, referring specifically to geotechnical/ tunnelling parameters.

Jan 1, 2008

By R. E. Cerullo

Many computer programs have been written which are capable of performing a least squares fit, both linear and nonlinear, to data gathered by the petroleum researcher. However, when the petroleum engineer tries to program methods of analysis he has used manually in the past, such as forecasting production by decline-curve analysis, more than a knowledge of the use of existing least squares programs becomes necessary. It is the intent of the authors to report the techniques used in the development of such a decline-curve program.

Jan 1, 1970

The Greymouth Coal field is situated on the West Coast of New Zealand's South Island and has been mined for coal for more than 120 years. The area covered in this paper is within the Rapahoe Sector of this field and contains >200 million tonnes of low ash, low sulphur, bituminous rank coal. Paper No 6, presented to the 19th Annual Conference of the New Zealand Branch of The Australasian Institute of Mining and Metallurgy in Christchurch in August 1985 by R G Bowman, explained 'A Geologist's View' of the 'Economic Potential of the Greymouth Coalfield', and describes previous geological assessments of the Rapahoe Sector.

Jan 1, 1989

By O. Leuangthong, M. Nowak

"The impact of high-grade data on resource estimation has been a longstanding topic of interest in the mining industry. Concerns related to possible over-estimation of resources in such cases have led many investigators to develop possible solutions to limit the influence of highgrade data. It is interesting to note that the risk associated with including high-grade data in estimation appears to be one of the most broadly appreciated concepts understood by the general public, and not only professionals in the resource modelling sector. Many consider grade capping or cutting as the primary approach to dealing with high-grade data; however, other methods and potentially better solutions have been proposed for different stages throughout the resource modelling workflow.This paper reviews the various methods that geomodellers have used to mitigate the impact of high-grade data on resource estimation. In particular, the methods are organized into three categories depending on the stage of the estimation workflow when they may be invoked: (1) domain determination; (2) grade capping; and (3) estimation methods and implementation. It will be emphasized in this paper that any treatment of high-grade data should not lead to undue lowering of the estimated grades, and that limiting the influence of high grades by grade capping should be considered as a last resort. A much better approach is related to domain design or invoking a proper estimation methodology. An example data-set from a gold deposit in Ontario, Canada is used to illustrate the impact of controlling high-grade data in each phase of a study. We note that the case study is by no means comprehensive; it is used to illustrate the place of each method and the manner in which it is possible to mitigate the impact of high-grade data at various stages in resource estimation."

Jan 1, 2015

By P. Wittke-Gatterman

ABSTRACT: A three dimensional constitutive law for swelling rock is presented. It can be applied to the osmotic swelling of mudstone as well as to the swelling of rocks containing anhydrite. It describes the development of time-dependent strains and stresses due to swelling considering elastic and viskoplastic behaviour. Furthermore an anisotropic swelling behaviour can be considered. This constitutive model was implemented within a numerical computation program according to the finite element method and calibrated on the basis of the results of measurements in the investigation drift of the Freudenstein tunnel which is completely located in the unleached Gypsum Keuper. A parameter combination could be found which results in a good agreement between numerical solutions and results of measurements. Therewith an analysis procedure which enables the design of tunnels in swelling rock is available. ZUSAMMENFASSUNG: Im vorliegenden Beitrag wird ein dreidimensionales Quellgesetz vorgestellt, das nach derzeitigem Kenntnisstand sowohl auf das osmotische Quellen von Tonsteinen als auch auf das Quellen anhydrithaltiger Ton- beziehungsweise Schluffsteine anwendbar ist. Das Stoffgesetz wurde in ein Finite-Elemente-Programm implementiert und anhand von Meßergebnissen des im unausgelaugten Gipskeuper liegenden Untersuchungsstollens des Freudensteintunnels kalibriert. Es ist gelungen, eine Kennwertkombination zu finden, mit der alle Meßergebnisse gut beschrieben werden können. Damit steht ein Bemessungsverfahren für Tunnel in quellfähigem Gebirge zur Verfügung. RÉSUMÉ: Dans l'article présent un loi de gonflement à trois dimensions est présenté, qui peut être appliqué aussi bien au gonflement osmotique de l'argile compactée q'au gonflement de l'argile compactée ou du limon compacté contenant de l'anhydrite. Le loi de comportement était implémenté dans un programme numérique d'éléments finis et calibré avec des résultats de mesures de la galerie de recherche du tunnel de Freudenstein, situé dans le Keuper de gypse non lessivé. On est réussi à trouver une combinaison de paramètres avec laquelle tous les résultats de mesures peuvent être bien décrits. Par ce moyen, une méthode de dimensionnement existe pour des tunnels dans de la roche capable de gonfler.

Jan 1, 2003

By R. E. Miller

Hoisting coal using water and air is a technology which has potential to improve the economics and safety of transporting coal. The Coal Air-Lift Hydrohoist is a prototype coal hoisting system developed by the U.S. Bureau of Mines (USBM). This paper discusses the method used to regulate the supply of water to the 50-m-high hydrohoist U-tube such that the pressure difference at the bottom of the U-tube is held constant. Maintaining a constant pressure difference results in a steady flow of slurry out of the hydrohoist.

Jan 1, 1995

By S. T. Kok

This paper presents a case study in West Malaysia for passive piles failure in very soft marine clay in open excavation. In this particular case, the thickness of the very soft marine clay ranges from 5 m to 7 m (16 ft to 23 ft) from the ground surface. Preliminary site investigation reported SPT ?N? value of zero for the very soft marine clay. The design was based on a deep foundation utilizing driven piles to support the superstructure. During pile cap construction, the piles were subjected to uncontrolled open excavation, inducing bending moment in the piles, resulting in some cracked and broken piles. Analyses were carried out using an existing three-dimensional finite element code with a non-linear soil model to predict the response of these piles during excavation. Finally, the predictions of pile responses during excavation were compared satisfactorily with the observed results.

Jan 1, 2009

By R. C. Urquhart, D. D. Howat, R. I. L. Guthrie

Heat losses from ladles during teeming by R. C. URQUHART, M.Eng. (McGiII), Ph.D. (Visitor). R. I. L. GUTHRIE, B.Sc. (Eng.) (London), A.R.S.M., Ph.D., D.I.C. (Visitor), and D. D. HOWAT, B.Sc. (Glas.), Ph.D. (Fellow) In an investigation of the loss of temperature by liquid steel during a teeming operation, a numerical technique was used to calculate the heat flows and the rate of temperature drop over the entire teeming operation. The calculations show that, before teeming, approximately 50 per cent of the heat loss is into the ladle wall at the level of the metal. As teeming progresses, the amount of heat lost by radiation to the wall above the metalline increases. The effect of variables, such as initial metal temperature, the preheat of the ladle and ladle cover, and delays, on the rate of temperature loss by the metal were determined.

Jan 11, 1973

The Raub Gold Mines are situated approximately in the centre of the Malayan Peninsula in the State of Penang. Part of the area, now known as "Raubhole," was opencut some 800 years ago by the Mon Khmers, a Cambodian people, whose vestiges mark numerous outcrops in South Eastern Asia. With their decline and extinction the work was abondoned, leaving a large pond in a dense thicket of Beluka (secondary growth).From the year 1885 onwards the history of Raubhole and the water therein records a chain sale starting from an enterprising local "Rajah," who had "assumed" authority, to an equally wakeful Singapore Arab; thence through the agency of a "down-and-out" beachcomber to a hopeful Australian company in the "goldbrick" days. Subsequent catastrophe on a depleted stringer was followed by reconstruction; the deserved reward of a long mining life, and an output of nearly 800,000 ounces of gold. Owing to the loss of notes and data stored in Singapore, this paper is not as complete as it should be, especially in respect to its metallurgical phases. Apologies are therefore tendered in advance for any deficiencies which may be noted.The necessary regional geological data have been taken largely from the admirable investigation of the Raub area by J. A. Richardson, A.R.C.S., B.Sc., F.G.S., of the Malayan Geological Survey*, and, throughout the paper, months represent lunar periods of 28 days and money is expressed in sterling.MINING SECTIONSAs shown hereunder the reef system has been divided by nature into seven isolated sections, which have been of necessity worked as seven separate small mines. From north to south these are:-(a) Sungei Agas consisting of very shallow workings to the south of, and adjacent to, a granite-porphyry mass known as Bukit (hill) Kajang. This area has not been worked for many years.(b) Bukit Malaka which is also shallow.(c) Bukit Jalis.(d) Bukit Koman which, with (c) and (e), consitutes the main workings and which has possibly been determined in depth.(e) Anderson Section.(I) Raubhole Section.(g) The workings under Raub Village.

Jan 1, 1945

Mineral production was of little significance in the country's economy, and Bangladesh was not a world-ranked producer of any mineral commodity during 1977. Natural gas was the most important mineral exploited; however, reserves were sufficient to allow for much greater production, Economically, Bangladesh made some progress in 1977-782 in its struggle against poverty, underdevelopment, and rapidly increasing population. The gross domestic product (GDP) grew 8%, mainly owing to a 13% increase in food grain production, the key economic indicator in this highly agricultural nation. GDP at current prices dropped slightly in Fiscal Year (FY) 1976.77 to $6.6 billion3 and rose to $7.2 billion in FY 1977.78. The population rose from 81 million in FY 1975-76 to about 85 million in FY 1977-78, resulting in an increase of per capita GDP from $83 to $85 during the same period. The high annual population growth rate, over 3% in 1976 and about 2.8% in 1977, was recognized by the Government as the main problem facing the country. Average density was 525 people per square kilometer. A similar density would have the entire world population living within the continental United States.

Jan 1, 1981

By F. S. McNicholas, R. L. Healy

NOTEWORTHY because of the amount of explosives used, the tonnage broken, and the wide range involved both vertically and laterally, was a large underground blast fired last November at the Hidden Creek mine, Anyox, B. C. Stoping methods and mining prac¬tices at the Hidden Creek mine have previously been described in the technical press. Earlier mining methods employed included shrinkage stoping, glory-holing, and "spiral" stoping. The latter especially has been a practice peculiar to the Granby company, having been used for years at its Phoenix mines and later at the Anyox property where conditions as to size of orebodies and strength of ground both in the ore and walls were similar. These methods all leave tremendous excavations supported at key points by pillars and braces that may only be safely mined by big blasts.

Jan 1, 1935

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 Jack T. Work

Spiraling costs in every segment of the open-pit mining cycle is a fact of life that every operator must reckon with. The introduction of various shock absorbing devices for rotary drilling is one recent innovation that may significantly reduce overall drilling cost, increase drill availability, and lower maintenance requirements. In a recent all-inclusive test in taconite ores, shock absorbers on Bucyrus-Erie BE 60R and Gardner¬Denver GD 120 rotary drills were directly responsible for overall savings of up to $41.06 per hour. What is It? A shock absorber is simply a device installed between the rotary drive head and drill steel that cushions the two. It functions in the same manner as springs and shocks on an automobile. Some benefits associated with use of the tool are readily apparent on a daily basis; other benefits are realized over longer time intervals and through continued use. A properly designed shock absorber will: •protect the drill from severe vi¬brations, improve rock bit performance, allow application of the best weight-on-bit and rotating speed under all drilling conditions, •function effectively over a wide range of applied bit weights, • have a spring rate soft enough to perform its primary function of absorbing both rotary and vertical vibrational forces generated by rough drilling, •be reliable and subject to as little maintenance as possible, •be easy to install and remove, and • be of such an economic benefit so as to offset the added expense of its application. A shock absorbing tool developed by BJ-Hughes Inc. was used in a recent test. The "Smoothdrill" is just one of the products currently available. This unit absorbs both rotary and vertical shock loads and has no mechanical parts so lubrication is unnecessary. A rebuild of the unit consists of removing the worn rubber element and inserting a new element, an operation taking less than one hour. Minimizing Vibrations Severe vibrations on a blasthole drill operating in broken and discontinuous formations have visible effects. These vibrations often cause structural damage when allowed to' continue, resulting in fatigue cracks in the mast and related structural components in the drill. When rough running formations are encountered, drilling must be interrupted and possibly shut down. Usually, the drill operator resumes drilling using less down pressures and various rotational speeds until firmer drilling is encountered. An effective shock absorber can substantially reduce these vibrational forces so more down pressure can be applied in bad ground. It is generally accepted that longitudinal vibrations and cyclic forces are more effectively reduced if a tool is designed to incorporate a relatively "soft" shock absorber. The softness of any shock absorbing tool is best judged by its spring rate-the weight required to produce a given amount of deflection, commonly expressed in units of kg per mm or pounds per inch of deflection. All shock tools use a resilient member such as rubber springs, steel springs, fluid, or gas springs to absorb

Jan 4, 1980