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By Henry Otto

THE anthracite industry can be divided into two parts-the underground, or mining, and the outside, or preparation or manufacture. To understand recoveries in the two branches, some of the history of the industry and the changes that have taken place in the past century should be considered. It is a long step from 1807, when 55 tons were produced in the Wyoming field, to 1917, the peak year, when 80,841,223 tons were shipped to market from all the fields. In 1820, the Lehigh Coal Co., the predecessor of the Lehigh Coal & Navigation Co., shipped 365 tons in arks down the canal of the Lehigh Navigation Co. The Schuylkill field was not opened until 1822, when 1480 tons were shipped. The Wyoming field really became a producer in 1829, when 7000 tons were mined and shipped. It is well to note, at this time, the passing of the Coleraine colliery after a life of 88 years; in collieries of this age will be found the. romance of the region, as well as the history of the changes to date.

Jan 1, 1925

?NWCC has the highest number of Aboriginal students of any post secondary institution in BC and the region served includes 25 bands ? Chair of the Board of Governors is Irene Seguin (Hagwiloo K?am Saxwhl Giis) from Gitwinksihlkw ? FN council ? 39 First Nations Members * focus is to develop policy recommendations to increase student success rates

May 1, 2009

By R L. Brathwaite, R Carver

The REGCHEM (Regional Exploration Geochemistry) database of open file mining company data, managed by GNS Science, has recently been upgraded with the compilation of additional data, especially for the Otago region (see http://maps.gns.cri.nz/website/minmap). In June 2007, data compiled for the Otago region included more than 2000 stream sediment samples from 19 surveys, more than 800 BLEG (bulk leach extractible gold) samples from 12 surveys and a few pan concentrate samples. The stream sediment samples were typically analysed for Au and As, and in many cases for other elements including Cu, Pb, Zn, Sb, W and Mo. The BLEG samples were analysed for Au and in some cases also for As. The main exploration target was mesothermal gold deposits in the Otago Schist, although one survey of the Otago Peninsula targeted potential gold deposits associated with the Dunedin volcanic complex. Geochemically, the mesothermal gold deposits are characterised by anomalous As and Au, with some also characterised by anomalous W and Sb, and these four elements are the best pathfinders in stream sediment geochemical surveys. The introduction of lower detection limits in Au analyses in the more recent stream sediment surveys and in the BLEG surveys enables the use of this element as the primary pathfinder for mesothermal gold deposits.

Jan 1, 2007

By Stephen B. Cheeseman

The quantity of data available and the rate at which we access such data are rapidly increasing. Electronic data capture systems, fleet management systems and a host of other technological advancements have created a constant stream of real-time, tactical data. However, are we taking advantage of this data? Are we converting data into useful information to aid in efficient decision-making? Mining operations are struggling with ?information overload?, finding it difficult to extract the benefits from vast stores of data. Without the necessary tools to facilitate a data filtering and information reporting process, most operations revert to old practises such as re-entering data into multiple spreadsheet reports. As a result, the ability to make effective use of data still eludes many mining operations. Some operations have taken audacious steps to rectify this situation. The De Beers Venetia mine in South Africa has implemented an integrated mining information technology solution that transforms their data into practical, usable information allowing staff and management to make decisions that improve efficiencies and reduce costs. In the absence of quantitative justification or ROI, De Beers took a risk in implementing change. Today, they are realising the benefits. This paper will unearth the information technology issues that surfaced during the Venetia implementation, then identify the benefits De Beers has obtained from deploying an integrated mining information technology solution at the Venetia mine.

May 1, 2002

By P. M. Prasad

Off-grade molybdenite concentrates, mainly derived from secondary sources as by-products of the processing of copper, uranium and tungsten ores, do not satisfy the purity requirements (percent MoS2) for the production of molybdenum bearing products. This investigation is a continuation of a successful effort to refine a low-grade molybdenite concentrate to prepare a high-grade MoS2 using a mixed acid (HF + HCl) leach procedure. Specifically, this investigation is concerned with an understanding of the separation chemistry underlying the removal of the oxide/silicate gangue and the base-metal sulfide associations present in the low-grade molybdenite by their selective dissolution in the two acids. Experiments were conducted on an off-grade concentrate containing 42.6% Mo. Results of the controlled dissolution tests indicate that both HCl and HF are suitable for the removal of the associated alumina and both work well for iron, nickel and copper. However, HF was found to be the most effective for dissolving silica/silicate and magnesia. An attempt was made to rank the leaching efficiencies of the acids used singly, sequentially or in a mixed mode. Scale-up (300 to 2,000 g) experiments were conducted to validate this approach. Excellent purification of the concentrate was possible by processing the off-grade concentrate with 10% HCl plus 15% HF at 363 K for 7.2 ks in open polypropylene reactors with internal stirring. These conditions leached practically all of the oxide and silicate gangue and 96% of the metallic impurities. Starting from the low-grade molybdenite concentrate (42.6% Mo; 71.1% MoS2) it was found feasible to obtain a refined product containing 97.8% MoS2, which is suitable for industrial use.

Jan 1, 2007

By Carlos Carrasco Arbieto

El óptimo conocimiento de los parámetros geológicos es importante para la economía de cualquier proyecto minero, dado que la previsión de las fluctuaciones de los riesgos geológicos, reduce la incertidumbre en el planeamiento de Mina. Por ello, la escaza información de sondeos reportada en algunos dominios geológicos de la mina Bunge, señala una falta de confiabilidad en las leyes de óxidos de interés como del modelo. En este sentido, el objetivo del presente trabajo es la creación de una metodología para la actualización sistemática del modelo de bloques a través de la información encontrada en los análisis químicos de los polvos de los barrenos para voladura y sondeo, tanto en los aspectos químicos y geométricos. Así, el Modelo de Bloques de Corto Plazo (MCP) sería el más idóneo puesto que el mapeo geológico en detalle y la simulación geoestadistica, genera una metodología que es aplicable para la actualización, tanto da geometría, como de las leyes de diferentes unidades litológicas que forman el modelo geológico da mina.

Sep 12, 2005

Ore Reserves estimation for the two producing copper orebodies at Isa Mine, Mount Isa, Queensland is discussed. The principal estimation techniques used and discussed are first, a computer based inverse power distance weighted assay meshing technique, and second, a manual arithmetic averaging technique. The principles involved in these techniques are compared, and their areas of application indicated. A general comparison of the estimation of reserves with eventual production is presented.

Jan 1, 1979

By Michael Arnold, Jonathan Delgado

In 2017, Bauer Foundation Corp. (BFC) was awarded the contract to install the deep foundations for the new 17-story Hotel Tower and the Low Rise Casino Expansion at the Seminole Hard Rock Hotel and Casino in Tampa, Florida. The site was underlain by extremely challenging Florida Limestone geology and surrounded by occupied existing buildings and infrastructure. To overcome the challenges of the difficult subsurface conditions, and to successfully complete the foundation installation without impact to the surrounding buildings and casino operation, Langan Engineering (EOR) and BFC were required to modify both the design and installation techniques during construction. The scope of work included 147 temporarily cased drilled shafts to depths up to 230 ft (70 m) below ground surface (BGS), 76 permanently cased micropiles up to 200 ft (61 m) BGS, and more than 300 augered-cast-in-place (ACIP) piles up to 125 ft (38 m) BGS. Voids and zones of high permeability in the limestone created many challenges for execution of the foundation scope including ACIP piles overbreaks of more than 400% above neatline volume, and construction induced ground subsidence/collapses adjacent to structures supported on shallow foundations. This paper will discuss site limitations, design and construction challenges, difficult geology, varied soil conditions, and lessons learned. PROJECT The project is located at Seminole Hard Rock Hotel and Casino Tampa, Florida, as shown in Fig. 1. Seminole Tribe, the owner, started the construction of a new 17-story Hotel Tower and the Low-Rise Casino Expansion at the beginning of 2017.

Jan 1, 2018

By C. D. Woodward

The Anaconda Copper Mining Co. purchases 25,000 kw. of electric power for its mining operations at Butte, Mont. This power is delivered, over duplicate feeders, in the form of 60-cycle, 2400-volt, three-phase current, to five compressor plants, where most of the energy is used for driving air compressors. At the compressor plants are located the switching apparatus for controlling the 2400-volt power and distributing it to the various mines. At these points, also, there are a number of motor-generator sets for converting the alternating current to 275-volt direct current for the haulage systems. Pole lines convey the powcr from the compressor plants to outdoor transformer substations at most of the mines. When it is not economical to distribute the power at the lower voltages in the mines, transformers and motor-generator sets are placed at strategic points underground. All power is purchased on a maximum-demand basis; therefore there is installed at one of the compressor plants an eight-element totalizing graphic wattmeter. This instrument records simultaneously the value of all power taken at the numerous points of delivery, which not only climinates the diversity factor but permits load dispatching between compressor and pumping plants, and thus materially reduces the maximum demand from the power system. As most of the mine hoisting is done by 90-lb. compressed-air winding engines, the air-compressor equipment for the winding engines and mining operations is quite extensive. The standard air compressor has a rating of 7500 cu. ft. per min. of free air, and most of the compressors are directly connected to synchronous motors. The synchronous motors are designed for 80 per cent. loading power factor, thus facilitating power-factor correction of total mine load. Consequently by cooperation with the power company, the voltage of the power received at the compressor plants is constant. In the mines there are installed an induction motor load of approxi-mately 10,000 hp., and 4500 kv.-a,, in transformer capacity. It is the practice to install 2200-volt motors in the mincs, except those rated below 50 hp, hence there are in operation underground about 5000 hp., in the

Jan 1, 1923

By Balesh W. Konda, Andrew B. Cecala

Face ignitions occurring during longwall mining are increasing each year and are expected to continue to increase as deeper and gassier seams are mined. Effective methane monitoring strategies are needed to supplement techniques developed either to control the ignition sources or to dilute the gas to an acceptable concentration. Present monitoring strategies do not always detect dangerous concentrations as rapidly as they should. In a number of instances, dangerous concentrations have been observed at the shearer, but are diluted to acceptable levels when measured at the tailgate monitoring location. To effectively monitor and control methane concentrations, methane liberation and emission patterns must be identified. This need has led to a joint research effort between the Canada Centre for Mineral and Energy Technology and the United States Bureau of Mines. By combining the knowledge and experience of both organizations, the methane hazard facing underground longwall operations can be addressed more effectively. A comprehensive plan was developed to monitor methane levels throughout the panel and for an entire longwall mining cycle. In June-July 1986, a case study was performed at the Cape Breton Development Corporation's Lingan colliery in Sydney, Nova Scotia. This initial study was performed on two advancing longwall panels. Methane concentrations and flow patterns from this study are described in this report. A similar study is planned on a retreating longwall panel.

Jan 1, 1987

By F. M. Goodwin, John Campbell, W. P. Yant, G. W. Jones

"INTRODUCTION The cooperative investigation dealing with the general hazards of combustible gases and vapors in manholes owned by the Edison Electric Illuminating Co. and the New England Telephone and Telegraph Co. in Boston, Mass. and surrounding territory, was continued during 1934.The method and procedure of conducting the survey for 1934 were the same as those followed heretofore.ACKNOWLEDGMENTSThe cooperative investigation was arranged through the interest and effort of F. D. Comerford, president of the Edison Electric Illuminating Co. of Boston; E. M. Farnesworth, Jr., vice president and general manager of the Boston Consolidated Gas Co.; and A. C. Fieldner, chief engineer, Experiment Stations Division, U.S. Bureau of Mines. Thomas H. Haines, superintendent, Distribution Department, of the Edison Electric Illuminating Co., cooperated in furnishing both men and information for the work.The New England Telephone and Telegraph Co., through Chief Engineer G. K. Manson, R. F. Esterbrook, H. G. Crush, and A. J. McCarron, cooperated by assigning a telephone company employee for the test truck. The company has borne its proportionate share of the expense and has taken an active interest in the work during the year. The test crew was operated under the direct supervision of John Campbell, superintendent of the Special Service Department of the Edison Electric Illuminating Co., and 7. M. Goodwin, vice president of the Boston Consolidated Gas Co."

May 1, 1936

By Blaisdell J. L, MacPherson G

The present communication records the results of a research investigation conducted in the Porcupine Gold Mines in Timmins, Onto. Soon after silicosis became a compansable disease in Ontario under the Workmen's Compensation Act in 1926, the attention of mine operators and physicians was drawn sharply to the prevalence and importance of this condition in the mining industry. A number of examining centres were established in Northern Ontario by the Workmen's Compensation Board, and the yearly X-ray examination of miners was made compulsory.Although working conditions were soon improved, the mining industry realized that they were confronted by a problem demanding basic research for its final solution. The late Sir Frederick Banting had, for a number of years, been interested in silicosis, and it was upon his suggestion that an experimental investigation was undertaken at the McIntyre-Porcupine Mines Ltd., Schumacher, Ont., in November, 1932. A preliminary report of this investigation was published in 1937 by Denny, Robson and Irwin and a further report by the same authors in 1939.Accepting the theory that silica exerts its injurious effect upon animal tissue through a slow transformation into silicic acid in the presence of body fluids; these authors assumed that if the solubility of the silicious material retained in the lung could be sufficiently reduced, the usual fibrotic response would be modified or would not occur. A search was therefore undertaken for some non-toxic compound that would fulfil this purpose. After investigating ma:qy substances, Denny and Robson discovered in 1936 that the presence of small amounts of aluminum powder almost completely inhibited the solubility of silicious material in vitro. An intensive study of the mechanism involved later showed that the reduction in solubility was due chiefly to a coating of the silica particle with a thin film of a gelatinous hydrated alumina which on drying formed the crystalline alpha aluminum monohydrate boehmite (AI203.H20). The presence of this absorbed layer on the surface of the quartz was indicated by -staining it with aurin (ammonium salt of aurin tricarboxylic acid) and proved by Germer and Storks by means of electron diffraction patterns.Inhalation experiments with animals were at once begun, using pure quartz dust with and without aluminum powder. (See original communications.) These observers showed that while typical silicosis was produced in about 5 months in the control animals receiving silica dust alone, the...

Jan 1, 1945

By D S. Nicholson, T Marshall

Reserves of high-grade quartz gravel, lignite and timber suitable for the production of silicon metal and ferrosilicon on large scale occur within 40 miles of Bluff Harbour. Undeveloped hydroelectric power resources on the Clutha River are located within 50 miles of the most promising quartz gravel deposits while opencastable lignite, potentially suitable for electric power production, occurs in the same locality as the quartz gravels. A preliminary study of production economics indicates that the commercial feasibility of silicon/ferro-silicon production would depend mainly on the cost of electric power, total capital cost of plant, and the market value of the products. The proximity of Bluff Harbour is advantageous for the export of products.

Jan 1, 1971

By Alain Duchesne, Dominique Fonfrede, Alan Broca

The technique involves the removal, in one piece, of an unwanted concrete pile section, exploiting the principle of crack propagation induced using gas pressure. The device, or pod, is made of a container in which an over-pressure is generated. After a predetermined time delay of 72 hours, gas and pressure are produced by the reaction between a calcium base chemical and water.

Jan 1, 2012

By Joshua A. Bennett

"Lawsuits where owners allege their property has been damaged by nearby blasting routinely costblasting companies, explosives engineers, and others in the field both time and money. When ownersfeel the vibration of a blast, they immediately begin to look for damage and usually find cracking thatwas, in fact, present prior to the blasting occurring. When those owners begin to talk to their neighbors and legal counsel, blasting entities suddenly have multiple lawsuits being filed as a result of the same blast."

Jan 1, 2016

By G. T. G. Emere

With the assistance and encouragement of Mr B.C. Alberts, the Institute's immediate Past President and Iscor's Senior General Manager: Mining, the Committee of the Johannesburg Branch recently organized a two day excursion for members to the northern Transvaal. The itinerary included visits to the Grootegeluk colliery, the Matimba power-generation utility, and the Thabazimbi iron-ore mine.

Jan 1, 1989

Éléonore Project Highlights Éléonoreis a multi-million ounce, high grade gold discovery in Québec Currently at the advanced exploration and engineering studies stage Excellent potential for expansion Underground mine with potential for small open pit Excellent infrastructure including road and high quality/low cost electricity within 70 km Les Mines Opinaca Ltée, a 100% subsidiary company of Goldcorp, was created to manage and operate the Éléonore Project

May 1, 2007

By Ulick R. Evans, Maurice Cook

The structural changes in metals brought about by annealing follow-ing a deformation at a low temperature has been the subject of many investigations. No less than eleven metals and alloys have been studied in some detail; namely, aluminum, tungsten,2 iron,3 copperI4 gold, zinc,6 cadmium, tin: lead: brass,1° and cupronickel. As a result, it is possible to frame a qualitative statement of the effect of the degree of deformation and the temperature of annealing on the structure finally attained.

Jan 1, 1925

By Andrew Cecala

During a recent National Institute for Occupational Safety and Health field evaluation of a newly designed filtration and pressurization system for an enclosed cab of a surface drill, it was determined that the drill operator's respirable-dust exposure was significantly increased during time periods when the cab door was opened to manually guide another section of drill steel into place to achieve additional cutting depth. Although no dust cloud was visible when the door was opened to perform this task, the drill operator's exposure was documented (over a three-day test period) to be nine times higher than when the cab door was closed. Even at this higher respirable-dust concentration, the drill operator's exposure remained well below the permissible exposure limit governed by the federal dust standard; however, an alternative method is being investigated to guide the drill steel in place in order to eliminate this increased exposure. .

Jan 1, 2008

By A Woodley, G Keir

The mining industry faces concurrent pressures of reducing water use, energy consumption and greenhouse gas (GHG) emissions in coming years. However, the interactions between water and energy use, as well as GHG emissions have largely been neglected in modelling studies to date. In addition, investigations tend to focus on the unit operation scale, with little consideration of whole-of-site or regional scale effects.This paper presents an application of a hierarchical systems model (HSM) developed to represent water, energy and GHG emissions fluxes at scales ranging from the unit operation, to the site level, to the regional level. The model allows for the linkages between water use, energy use and GHG emissions to be examined in a flexible and intuitive way, so that mine sites can predict energy and emissions impacts of water use reduction schemes and vice versa. This paper examines whether this approach can also be applied to the regional scale with multiple mine sites.The model is used to conduct a case study of several coal mines in the Bowen Basin, Australia, to compare the utility of centralised and decentralised mine water treatment schemes. The case study takes into account geographical factors (such as water pumping distances and elevations), economic factors (such as capital and operating cost curves for desalination treatment plants) and regional factors (such as regionally varying climates and associated variance in mine water volumes and quality).The case study results indicate that treatment of saline mine water incurs a trade-off between water and energy use in all cases. However, significant cost differences between centralised and decentralised schemes can be observed in a simple economic analysis. Further research will examine the possibility for deriving model up-scaling algorithms to reduce computational requirements.CITATION:Keir, G and Woodley, A, 2013. Regional trade-offs between mine water and energy use - a water treatment case study, in Proceedings Water in Mining 2013 , pp 21-28 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013