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By C. J. Bise

Virtual Reality (VR) is a concept in which the human experience of perceiving and interacting with a computer-modeled environment is achieved through the use of sensors and effectors. It is an advanced fonn of computer graphics where the images are generated based upon where the user looks and how the user moves. As personal-computer-based (PC-based) instruction gains acceptance as an innovative approach to providing safety training, VR offers the capability of providing a multisensory, rather than merely a multimedia, mode of presentation. VR has been effectively used by the military for training tank commanders and by hospitals for training surgeons. However, these applications have been limited to small numbers of highly skilled participants. The purpose of this paper is to examine VR's potential for enhancing the hazard awareness of larger numbers of individuals in a broad-based approach to mine safety training, such as new-miner, annual-refresher, and independent-contractor training.

Jan 1, 1996

By G. T. Austin

Every year the United States consumes millions of dollars worth of abrasive materials as blasting media. Entrained in either a gas or liquid stream or propelled by paddles or wheels, they are directed onto the surface of another material to modify that surface. The modifications to impacted surfaces include cleaning, cutting, deburring, etching, finishing, and peening. Blasting media can be either organic or mineral abrasive materials. Information and data presented are for only a portion of the mineral abrasives, they are; fused aluminum oxide, coal slag, copper slag, garnet, metallic shot and grit, nickel slag, olivine, silica sand, silicon carbide, and staurolite.

Jan 1, 1994

By J. Engelbrecht

Understanding the deportment of minerals in size fractions has already led to improvements in the flow sheets for platinum minerals beneficiation. There are, however, more potential changes in the flow sheets that may improve the recovery of platinum group metals or reduce the costs of beneficiation before refining. Based on known technology of pre-concentration, milling, gravity concentration, flotation, and magnetic separation a number of potential alterations or additions can be considered and motivated based on the mineral deportment in size fractions.

Jan 1, 2012

By Merrill, Charles White

MOST extraordinary of the technical developments in placer gold mining during the last five years has been the rise of the dragline dredge, by which is meant a floating washing plant for auriferous gravel, fed by a dragline excavator. The idea originated in the fall of 1933, when Horace Onyett constructed a floating washing plant to which gravel was delivered by a dragline excavator standing on dry land. Onyett's operation near Oroville, Calif., and another started by H. F. England later on Wyandotte Creek, Butte County, Calif., yielded '75 oz. of fine gold before the end of 1933. Although the first operation was abandoned shortly as un- profitable, the dragline-dredge method of gold recovery soon began to expand at a boom rate. As a matter of interest, the Onyett operation was taken over later by Lord and Bishop, who are re- ported to have succeeded in making it the first financially successful drag- line dredge. In California alone drag- line dredges produced $3,294,970 worth of gold in 1937, and the pros-

Jan 1, 1938

By L. A. Morley

Volume III of the final report examines the indication versus interruption procedures used on motion-drive power equipment, with emphasis on surface excavators. The report begins with a review of the electromechanical acid conversion used with the Ward-Leonard control system. Protection criteria for the drive-system components are then discussed. Fault sources and fault calculations for both the ac supply source and dc power loop are introduced to assist in discussing indication and interruption procedures. The subject is then expanded to examine the dynamic process of the machine and determine the effects of fault current and position of the machine to allow for an orderly shutdown. With this analysis, possible indication an interruption procedures are given for the four-quadrant duty cycle of excavators. The report concludes by introducing other mining operations that utilize similar motion-drive systems and also static (solid-state) drives and recommends further research in these areas, as well as a more detailed examination of the dynamic fault analysis for excavators.

Jan 1, 1982

By Paul A. Rittenhouse

First of all, I want to thank John Dunlap for asking me to this AIME meeting in Denver. I was first introduced to Denver and The Rocky Mountains more than ten years ago and immediately decided it was one of the most attractive spots in the world. I've come back many times since and still welcome any opportunity to return, even if it means I have to prepare and give a paper on potash. When John Dunlap gave me this assignment, he told me that the program would include papers on the geology of potash, papers on new discovered potash deposits and new mines and asked me to discuss potash from the commercial point of view. He also asked me to include a supply/demand outlook for potash. However, one thing he did not mention was "how far into the future he wanted me to look" and it seems to me the time element is a crucial factor to you who are both geologists and miners as well as to me. In your case, you have to look far enough into the future to give you time to explore, find, evaluate, develop, and bring into production a commercial deposit. My mining associates and friends don't agree on how long that takes but it's probably somewhere in the range of eight to fifteen years. But, they all agree on one thing and that is that the time required is continually getting longer. Now my time problem is just the opposite. It is "relatively" easy, and I stress relatively, to identify and evaluate the importance of the various factors that impact on both the supply of and demand for a commodity such as potash if the time period is today. It gets a little tough if one has to project into tomorrow or next week or next month. And when we start talking in terms of a year, five years or ten or fifteen years, things really get sticky and the old crystal ball becomes mighty cloudy. But we economists and forecasters are not known for our temerity so let me get on with the job at hand and take a look at the world potash supply/demand outlook.

Jan 1, 1978

By Marvin S. Seppanen

Computer programers are often required to make modifications to unfamiliar Fortran routines. This Bureau of Mines report describes a computer program designed to aid the programer in such a situation by reorganizing: Fortran routines. This reorganization includes a sequential renumbering of the routine's statement numbers, a sequential renumbering, and relocation of format statements, an alphanumeric reordering of dimensioned and typed variables, a uniform pattern of text spacing, and a sequential numbering of the records in the final Fortran routine. The computer program has been extensively tested by the author and has proved to be a valuable tool for reorganizing Fortran routines developed under contract and later utilized by the Bureau, and for preparing routines for publication.

Jan 1, 1975

By W. M. Cross

The use of fillers and reinforcements for plastics has increased considerably over the past few decades. For example, in the 1980's the average growth rate of filler use was 5.8%. [Katz and Milewski, 1987] Similar filler use growth rates occurred in the 1970's due largely to the increase in price of petrochemical starting materials for plastics. While filler use is still sometimes predicated on the cost benefits associated with their addition to the plastic, other mechanical and performance advantages associated with filler addition are being realized, and account for most of the increased usage. Plastic filler types are many and varied, and include both inorganic minerals/metals and organic compounds, with the former type being, by far, the more common. Common mineral fillers include oxides, including both natural and synthetic silica; carbonates, particularly calcium carbonate; clays such as kaolin; and silicates like mica and talc. It has been recognized that a number of factors influence filler performance, including particle size, shape, surface area, and hardness to name a few. In addition, the interaction between the filler and the plastic is of paramount importance as this interaction will determine the wettability, bonding and the adhesion between the two materials, and ultimately, the mechanical properties of the composite. Froth flotation has long been recognized as a viable process to separate different mineral types. [Leja, 1982] Prior to flotation the minerals are liberated from the ore by comminution. The mineral particle size range produced by this comminution process is typically between 300 and 10 microns. This size range is also typical of mineral fillers for plastics. The size similarity between mineral fillers and minerals concentrated by froth flotation is only one of many similarities that can be found.

Jan 1, 1997

By Servant S

In the mine of this study, cemented hydraulic backfill is placed under the form of a slurry at a percentage of solid by weight varying from 50 to 65 per cent. This slurry settles and cures in the stope. During this process an important amount of water must be drained from the scope. Field observations in the case studied here show that the geometry of the drains system has a significant impact on the drainage of the stopes. The mode of filling produces a backfill showing an evident stratification typical of a sedimentation process. In situ observations on this material show that this stratification translates into a very strong heterogeneity in the physical properties of the cemented backfill. This heterogeneity should affect the hydraulic conductivity of the backfill in the scope. In order to study this aspect, finite element simulations were performed. This paper presents the results of these simulations, where the impact of this stratification on hydraulic conductivity is related to the performance of the backfill drainage system for various geometry. This preliminary study is aimed at providing a better understanding of the role of the drains in the dewatering process of the backfilled stope in the case of this Mine.

Jan 1, 1998

THERE are certain facts that the mining industry in Australia is faced with at the present moment which may be accepted as axioms. The industry is at a low ebb, as evidenced by statistics. Metals form the basis of all modern industries, and are necessaryfor the welfare of Australia. Mining is a wasting asset. Every ton of ore extracted is one ton less which c.annot be made good, and it should be our duty to get as much profit froin that ore as possible, otherwise there is a permanent loss to the country.The metal market cannot be controlled by Australia; it is more or less an international matter. Australia has not been thoroughly prospected. There are no mines being developed that are likely to replace those which are being depleted.Our mining engineers are as capable as those in other parts of the world, and have made good where they have been given a chance. There is no one cause for the present depression; there are several, more or less, interwoven. Of course, the war has had an adverse effect, but that has only dislocated things temporarily; it upset our markets, influenced the price of metals, and affected the labour market and cost of stores. Labour troubles made their appearance before the wave of unrest swept over the world. The cause of labour discontent must be investigated, and if possible removed. As each industry has .its·own problems, miners must inquire into their special problems, as there is no sovereign remedy that will suit all cases.It is obvious that we cannot mine ore if we do not know where it is; therefore, the first thing is to discover workable deposits.

Jan 1, 1919

The Bureau of Mines is operated to assist in promoting economic development through increased efficiency in the mining, preparation, treatment, and utilization of mineral substances; to aid in conserving mineral resources through preventing waste; and to help the mining industry improve health conditions and increase safety. Accomplishment of those ends is sought through investigation of scientific, technologic, and economic problems of the, mineral industries and dissemination of resulting information. Building materials of mineral origin constitute an important product of mining, and the Bureau makes studies of these in the various fields mentioned. The following commodities come within this classification: Asbestos, anhydrite, asphalt, cement, clay and clay products, diatomite, dolomite, glass and mineral wool, granite, greenstone, gypsum, lightweight building materials, lime, limestone, magnesite, marble, sand, sand and gravel, sandstone, sand-lime brick, slate, soapstone, and trap rock.

Jan 1, 1937

By Farnham. G. S.

It is difficult co know how to deal with this subject before a group having such mixed interests. The mining man is not coo concerned with the problems of alloy research. The engineer is more interested in properties of materials than how these properties can be achieved. The business man feels that scientific history and prognostication are not for him, predicting trends or possible developments in the economic field being a more than sufficient occupation. Yet the application of physical metallurgy research to industry is of importance to miner, engineer, and business man, for only through such application can the continuing existence of industries manufacturing or consuming metals be assured. History shows that hard work does not guarantee industrial survival. For instance, the Bessemer method of steel making superseded puddling operations; it, in its turn, has been largely displaced by open-hearth processing; later, steels made in electric-arc furnaces displaced open-hearth products in the quality field; and now, very specialized steels are being made in high-frequency rather than in arc furnaces. It is apparent then, if industry is co remain healthy, complacency must give way co imaginative planning, based on a thorough knowledge of production technique, a knowledge supplied by efficient research.

Jan 1, 1947

By S. J. Aresco

The Bureau of Mines has been active in promoting the purchase of coal for Government use under specifications that define the requirements in terms of heating value of the coal, expressed in British thermal units, and the composition as shown by proximate analyses. To these, when required, are added the ash-softening temperature, the free-swelling index, and the Hardgrove grind-ability index. Under most of these specification contracts the bidders guarantee the quality of the coal, and that guaranteed by the successful bidder becomes the standard of his contract. The deliveries are sampled in accordance with instructions4 issued by the Bureau of Mines; the samples are analyzed in the Bureau laboratory to determine whether the coal is of the quality guaranteed by the contractor; if it is not, a price adjustment is made. Analyses of the delivered coal and tipple samples (samples collected at mine tipples as coal is being loaded into railroad cars or trucks) provide valuable data for use in evaluating future bids. In addition, the continuous sampling of coal as delivered is a check on the practical results obtained in burning the coal.

Jan 1, 1965

By Mark R. Jolly, Jean-Christophe Gebelin, Aleksander Cendrowicz

"Injection of wax patterns is the first stage of the multi-stage process of investment casting. The quality of the final casting and its dimensional accuracy is highly dependent on this stage of the process. Pattern waxes used in the industry behave in a complex visco-elastic-plastic manner. The modelling of such material behaviour is therefore not simple.In this paper a number of configurations of die will be shown in which the injection of the wax has been carried out for a range of processing conditions. Some of the dies are transparent and the movements of wax front observed can be compared with those predicted by simulation. Surface defects in final components will also be shown and compared with the location predicted by simulation software. Some discussion will be presented on the limitations of the software used and the time-scales achieved for practical use as a design tool within the foundry environment. IntroductionThis paper presents the research activities carried out at the University of Birmingham on the modelling and prediction of the behaviour of industrial investment casting waxes during the injection of wax patterns. These research activities are done in the context of a more global study of the fundamental aspects of the investment casting process, the FOCAST project. Regarding the wax injection process, the aim of the project is to achieve a better understanding of the key factors that will lead to better castings. The filling of the die during the injection has been studied. Some other phenomena such as shrinkage/warpage or creep under residual stresses are also studied, but not presented here. Two commercial investment casting waxes have been characterised in order to model their behaviour and predict mould filling and subsequent defects.This paper will present the models that have been used in our work, the simulation packages used, the experiments carried out to validate the modelling and exhibit the defects due to bad filling, and finally the numerical simulation results."

Jan 1, 2001

By G. S. Hume

FOR MANY YEARS Canada lived in the hope of attaining a substantial production of petroleum and natural gas that, to geologists familiar with the sedimentary basins of this country, seemed an entirely reasonable expectation. There have been surges of exploration activity stimulated by oil and gas discoveries and development such as occurred in Turner Valley. However, it was not until the Leduc field in Alberta was found in 1947, and the significance of that discovery was realized, that the search became really intensive and continuons. Expansion now has become a matter-of-fact attitude based on results which would have been considered impossible of achievement a few years ago.

Jan 1, 1957

By A. J. Rigby

Anode vessels are often relined with refractory every one to two years and a typical reline time can take between 16-20 days. Modem refractory designs using dense, corrosion resistant brick applied directly to the vessel shell in the high wear areas around and above the tuyeres and at the slagline can yield a lining life of up to 4-5 years before a complete reline is necessary. Installation methods using brick delivery on roller conveyors through an endwall access port and complete anchoring of the brick to allow for lining self-support can take days off the installation time. It is possible, therefore, to reduce the refractory relining period by 50% and increase lining life by 100% compared to typical anode repair schemes. Cu2007

Jan 1, 2007

By M. Myllymäki

"Pre-treatment of mill feed in a minerals processing plant enables for higher production efficiency per ton of product, reduction of consumables and diverting mineral feed types. Sensor based particle sorting allows for pre-concentration of the run-of-mine (ROM) material prior to other concentrating process. Various sensors provide different responses from the minerals in measured particles. The capability of “accepting” or “rejecting” particles based on sensor responses is investigated in specific test work for each project. Modern sorting machines use pneumatic actuators to divert the reject particles from the material stream. This paper discusses the incorporation of ore sorting test work in processing and plant design. When taking the effects of a sorting circuit into account early in the process planning phase, the downstream process can be adequately sized and impacts evaluated. Potential benefits include but are not limited to increased head grade, lower tonnage to the mill, increased mining operations, removal of deleterious elements and changed properties in the process feed. In a case study we present the Keliber lithium project in central Finland. The plant will produce 9000 tons of lithium carbonate per year from a spodumene ore. Ore sorting and flotation tests were carried out in laboratory and pilot scale. Process models were designed and simulations performed using Outotec’s HSC Chemistry Simulation software. Changes in the flotation performance (grade, recovery, impurity levels) were simulated with and without the pre-concentration of the ROM material. The metallurgical performance and mine economics of the different operational scenarios were evaluated using the Ore-Met optimizer module of the simulation software.INTRODUCTION Challenges in the recent years such as declining ore grades, increasing energy prices, scarcity of water and increasing environmental regulations raise the demand for more efficient processing technologies. Sensor based sorting offers a method for pre-concentration or waste rejection at an early process stage. The technology analyzes each rock particle separately for their unique physical and chemical properties, and diverts the particles into separate material streams by high pressure air jets. Successful implementation relies on ore heterogeneity, differential sensor response and suitable feed preparation."

Jan 1, 2018

By Anievas JB, Sevillano AC

This paper describes the acquisition, exploration, development, initial operation and subsequent financing of the Bulawan mine by means of a listing on the Toronto Stock Exchange of a subsidiary of the parent company, Philex Mining Corporation.Located on the island of Negros in the Philippines the property is unique on at least two counts: it is a disseminated gold deposit that occurs in a region of predominantly porphyry copper mineralisation; and it is a gold deposit that is mined by a bulk method of extraction (front and block cave) instead of the normal selective mining methods.

Jan 1, 1997

By C. P. McCormack

THE Cuyuna manganiferous iron ores can be a principal source of manganese for the iron and steel industry in the United States, provided metallurgical methods as a whole are adjusted so as to use run-of-mine ore. The use of manganese in steelmaking is growing. Increasing amounts of impurities in raw materials call for more manganese, a constant cheap supply of which is wanted. There are few deposits of ore in the United States carrying over 35 per cent. manganese that can be mined and marketed at a profit in normal times. We are largely dependent on foreign ores. The small domestic deposits should rightly be held in reserve for an emergency, such as a war, when importation might cease. Even the production from lean ores, concentrated it may be, might not carry us through a protracted stringency. The Cuyuna district is, therefore, during normal times capable of supplying a large total of manganese. The ores are iron ores containing 5 to 25 per cent. of manganese with the inverse range of 52 to 28 per cent of iron. The manganese costs no more per unit in the ore than the iron, because cost of mining, largely by open-pit methods, is not affected by the manganese content. The manganese units should, perhaps, command a higher price, but as their value is contingent on metallurgical practice, a higher price may be justified only when a shortage in manganese occurs. Manganiferous iron ores can never entirely supplant straight manganese ores though methods are employed that will permit them to do so partly. For the manufacture of ferromanganese, ores carrying above 42 per cent. manganese are needed. Ores with manganese running between 20 and 42 per cent. are used for making spiegeleisen. But established practice in certain plants, based on the admixture of manganiferous iron ores to straight iron ores has greatly lessened the consumption of high-priced, scarce, manganese alloys with good results.

Jan 2, 1925

By Carel Robinson

MECHANIZATION of coal mine, is radically changing the requirements for under-ground transportation. It has increased materially the need for reliability and belt conveyors are the most dependable means of moving coal away from the place where it is mined. Their record of freedom from delays is almost 100 per cent. Why then are- not belt conveyors in more general use. Part of the answer lies in the pour records made at some of the earlier installations, and in the fact that belts have so long been identified as a type of equipment suitable, in the main, only to thin seams. Another reason is lack of knowledge of the full potentialities of belt transportation.

Jan 1, 1941